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Outcome of patients with bulky IB cervical squamous cell

Original Article

Outcome of patients with bulky IB( 6cm)cervical squamous cell carcinoma with and without cisplatin-based neoadjuvant chemotherapy

Peng-Hui Wang a,b,c,d,*,h,Yen-Hou Chang a,h,Ying-Hui Yang a,d,Wen-Hsun Chang a,d, Shu-Yun Huang a,d,Chiung-Ru Lai e,Chi-Mou Juang a,Yi-Jen Chen a,

Huann-Cheng Horng a,Kuo-Chang Wen a,Heung-Tat Ng a,f,Chiou-Chung Yuan g,

Kuan-Chong Chao a,Ming-Shyen Yen a,*

a Division of Gynecology,Department of Obstetrics and Gynecology,Taipei Veterans General Hospital and National Yang-Ming University,Taipei,Taiwan

b Immunology Center,Taipei Veterans General Hospital,Taipei,Taiwan

c Department of Medical Research,China Medical University Hospital,Taichung,Taiwan

d Department of Nursing,Taipei Veterans General Hospital and National Yang-Ming University,Taipei,Taiwan

e Department o

f Pathology,Taipei Veterans General Hospital and National Yang-Min

g University,Taipei,Taiwan

f Foundation of Gynecologic Cancer,Taipei,Taiwan

g Department of Obstetrics and Gynecology,Taipei Medical University-Shuang Ho Hospital,New Taipei City,Taiwan

a r t i c l e i n f o

Article history:

Accepted22May2014

Keywords:

bulky cervical squamous cell carcinoma cervical cancer

neoadjuvant chemotherapy

radical hysterectomy a b s t r a c t

Objective:To study the surgical morbidity and outcomes of patients with markedly bulky cervical squamous cell carcinoma( 6cm Cx-SCC)who underwent radical hysterectomy(RH)with and without neoadjuvant chemotherapy(NACT).

Materials and methods:This retrospective study enrolled patients with International Federation of Gy-necology and Obstetrics(FIGO)IB markedly bulky Cx-SCC who were treated with either three courses of weekly single agent cisplatin NACT(50mg/m2)and subsequent radical hysterectomy(NACT-RH)or direct radical hysterectomy(RH)between1996and2001.A total of60patients ful?lled the criteria, including35and25patients with NsACT-RH and RH,respectively.

Results:There was no statistically signi?cant difference in basic characteristics between the two groups, except the smaller pathological tumor size,less blood loss,and lower immediate complication rate in the NACT-RH group.Median survival was143.8months in the NACT-RH group and129.8months in the RH group,respectively,without a statistically signi?cant difference.Multivariate analysis showed that large pathological tumor size[hazard ratio(HR)10.66,95%con?dence interval(CI)2.93e38.80],the presence of para-aortic lymph node metastases and an immediate complication(HR8.33and4.55,95%CI1.66 e41.75and1.35e15.27,respectively)contributed to a worse outcome.

Conclusion:Weekly single agent cisplatin NACT indeed reduced the pathological tumor size and im-mediate complication rate during the RH,supporting the feasibility of subsequent RH in the management of patients with bulky Cx-SCC.

rights reserved.

Introduction

Cervical(Cx)cancer is still a serious health problem,second only

to breast cancer as the most common female malignancy in both

incidence and mortality worldwide[1].In recent years,both overall

survival(OS)and disease-free survival rates have been signi?cantly

improved as a result of advances in the technologies of surgery,

chemotherapy(CT),and radiotherapy(RT)[2].However,patients

*Corresponding authors.Division of Gynecology,Department of Obstetrics and Gynecology,National Yang-Ming University School of Medicine,Taipei Veterans General Hospital,201,Section2,Shih-Pai Road,Taipei112,Taiwan.

E-mail addresses:phwang@https://www.wendangku.net/doc/6115531080.html,.tw,phwang@https://www.wendangku.net/doc/6115531080.html,.tw(P.-H.Wang), msyen@https://www.wendangku.net/doc/6115531080.html,.tw(M.-S.Yen).

h Both of these authors contributed equally to this

work.Contents lists available at ScienceDirect

Taiwanese Journal of Obstetrics&Gynecology journal h omepage:ww w.tjog-on

https://www.wendangku.net/doc/6115531080.html,

https://www.wendangku.net/doc/6115531080.html,/10.1016/j.tjog.2014.05.001

Taiwanese Journal of Obstetrics&Gynecology53(2014)330e336

with early-stage bulky Cx cancer are dif?cult to manage,because of the high recurrence rate and worse prognosis,compared to those with smaller tumors at the same stage[3].In this situation,the role of surgery[radical hysterectomy and pelvic lymph node dissection (RH and PLND)]is controversial[2],compared with the role of concurrent chemoradiotherapy(CCRT).CCRT is now considered the treatment of choice for patients who are not candidates for initial surgical therapy[4e7].In clinical practice,Cx cancer is classi?ed according to the clinical International Federation of Gynecology and Obstetrics(FIGO)staging system[1],and this is mainly based on clinical examination,which makes the selection of those that will bene?t from surgical intervention much more dif?cult. Therefore,modi?cation of the treatment strategy,including the use of neoadjuvant chemotherapy(NACT),RT(external beam RT or brachytherapy)and CCRT,is much more frequent either before or after surgery.

To perform successful surgery,the induction of tumor shrinkage might be of most importance.This not only facilitates radical excision but also makes reconstruction easier.Although many strategies can be used to bring about tumor shrinkage,chemo-therapy may be effective.NACT is well accepted in the management of various types of tumor,such as breast cancer[8].However,the application of NACT for Cx cancer is debated,although it is often used in Asia,Italy,and South America[2].The theoretical rationale for the use of NACT in Cx cancer includes the aforementioned in-duction of tumor shrinkage to facilitate radical excision,and a possible sterilization of lymph nodes and parametrial tissues, thereby reducing the risk factors of adjuvant therapy after surgery [1].NACT regimens for Cx cancer vary,ranging from single-agent to many forms of multiagent regimens.In addition,the therapeutic interval also varies,ranging from every week to every2,3,or 4weeks[9e15].The clinical effects of NACT are not always consistent with the theoretical bene?ts,and that is why there is a great deal of con?icting data in the literature[9e15].The available reports on the effect of NACT on Cx cancer are mainly with regard to FIGO IB and IIA bulky tumors,sometimes up to stage IVA[9e16]. The heterogeneity of the study population,including the differ-ences in stage and cell types,and comorbidity with other medical or surgical illnesses make it dif?cult to reach a conclusion[9e16].In addition,there is no study addressing markedly bulky Cx squamous cell carcinoma(Cx-SCC)( 6cm).Therefore,we conducted this retrospective study to investigate the effect of NACT on the man-agement of early-stage bulky Cx-SCC before surgery.

Materials and methods

The population of this study was derived from the Cancer Reg-istry in the Department of Obstetrics and Gynecology of Taipei Veterans General Hospital.All patients with markedly bulky 6cm Cx-SCC undergoing RH and PLND between1996and2001were evaluated.The study aimed to compare the difference between weekly cisplatin-based NACT-RH and RH as an initial therapy for patients with 6cm Cx-SCC.To make this study even more uni-form and consistent,eligibility criteria were as follows:histologi-cally veri?ed uterine Cx-SCC;locally advanced stage FIGO IB disease without parametrial invasion or distant metastases;initial mag-netic resonance image-or computed tomography-measurable tu-mor diameter S6cm in size;age younger than65years with a life expectancy 1year;World Health Organization performance status of0-2,treatment with type III RH and pelvic and para-aortic lymphadenectomy,no prior treatment with RT or CT,but three courses of weekly cisplatin50mg/m2were permitted;absence of prior malignant diseases or surgical illness,but cesarean section was permitted;and adequate renal,pulmonary,hepatic,bone marrow,and cardiac function.

Basic characteristics of the patients,including surgical param-eters and complications,were recorded.Immediate complication included visceral organ injury,prolonged hospitalization because of instability or signi?cant delay( 7days)of immediate post-operative adjuvant therapy(such as CT,RT,or CCRT);dif?culty in urination and constipation were https://www.wendangku.net/doc/6115531080.html,te complication included any therapy-related sequelae,such as long-term ureter or urethra catheter use( 12months),radiation colitis,and cystitis. We used the following parameters to de?ne the radiation colitis or radiation cystitis.The diagnosis of radiation colitis and/or cystitis was made when those patients who had at least one attack of anal bleeding and gross hematuria that required medical care for relief and the diagnosis of radiation colitis and/or cystitis had excluded other radiation-unrelated or tumor-related possibility at?rst,such as infection,acute gastroenteritis,hemorrhoid,or tumor recurrence.

Periodic follow-ups of patients,including postoperative adju-vant therapy,such as CT,RT,or CCRT in accordance with the pa-tients'risk analysis[17e22],physical examination,vaginal cytology, and imaging or intravesical ureterography,continued until the patients died or for more than5years after surgery.To determine an appropriate decision point for the continuous data,such as age, tumor size,blood loss,and number of lymph nodes,the receiver operating characteristic was used[23].

Survival was determined on the basis of treatment and patient outcomes.Estimates of the proportion of OS were calculated by the Kaplan-Meier procedure,and differences in survival were evalu-ated via the log-rank test.Covariance analysis and the hierarchic Chi-square test were used to control for potential confounding factors in the comparison of clinicopathologic characteristics and risk factors.The log-rank test,hazard ratio(HR),and95%con?-dence interval(CI)of mortality from cancer were calculated via the Cox proportional hazards model with univariate and multivariate analysis of OS.Statistical signi?cance was determined by an un-paired two-tailed Student t test using a pooled estimator of vari-ance,and was de?ned as p<0.05.SPSS version20(SPSS,Chicago, IL,USA)was used for statistical analysis.

Results

A total of60patients ful?lled the aforementioned criteria and were enrolled into the analysis.Thirty-?ve patients received three cycles of weekly intravenous cisplatin50mg/m2-based NACT,fol-lowed by RH and PLND and para-aortic lymph node sampling (NACT-RH group)on Day18after the?rst course of NACT.The remaining patients(n?25)underwent RH and PLND and para-aortic lymph node sampling(RH group).Follow-up ranged from 11months to205months(median138months).

There was no statistically signi?cant difference in age,initial image tumor size,number of removed lymph nodes,cell grade,and presence of deep stromal invasion,vaginal invasion,parametrial invasion,lymphovascular invasion,and pelvic or para-aortic lymph node invasion between the two groups(Table1).The percentage of patients in both groups who were treated with postoperative adjuvant therapy was also similar.The mortality rate seemed to be lower in the NACT-RH group(37.1%in the NACT-RH group and 48.0%in the RH group),although without a statistically signi?cant difference.Pathological tumor size,estimated blood loss during operation,and immediate postoperative complications were signi?cantly different between the two groups.In the NACT-RH group,the pathological tumor size was signi?cantly smaller (4.5±1.4cm vs.5.7±0.8cm,p<0.001).In addition,a lesser amount of estimated blood loss during the RH procedure was also noted in the NACT-RH group(558±1328mL vs.930±356ml, p<0.001).The immediate postoperative complication rate overall

P.-H.Wang et al./Taiwanese Journal of Obstetrics&Gynecology53(2014)330e336331

was 20%,but was lower in the NACT-RH group (5.7%vs.32%,p ?0.007).Almost three-?fths of patients were treated with postoperative adjuvant therapy,such as CCRT,RT,and CT.

During the follow-up,25patients had recurrence,and all died of Cx cancer-related diseases.The overall survival rate was 58.3%.In the NACT-RH group,the OS rate was 62.9%,compared with 52%in the RH group (Fig.1).The median survival time of the patients in the NACT-RH and RH groups was 143months (ranging from 23.4to 205.7months)and 129months (ranging from 11.2to 203.5months),respectively.Although the OS rate of the NACT-RH group seemed to be longer,it did not reach a statistically signi ?cant level (p ?0.512).The Kaplan-Meier procedure identi ?ed the sig-ni ?cant prognostic factors as (A)pathological tumor size ( 5.3cm vs.>5.3cm,p <0.001),(B and C)presence of pelvic or para-aortic lymph node metastases (no vs.yes,p <0.001),(D and E)presence of immediate or late complication (no vs.yes,p ?0.002,and p ?0.020,respectively),and (F)recurrence (no vs.yes,p ?0.004)(Fig.2).In addition,patients who had a long-term urinary dif ?culty had a worse outcome (HR 2.93,95%CI 1.21e -7.08).

Because the decision of postoperative adjuvant therapy was made in accordance with the patients'risk analysis [17e 22],and most decisions were based on histopathological ?ndings,such as a large-sized tumor,positive invasion of the cut end,presence of pelvic and/or para-aortic lymph nodes,and deep stromal invasion (Table 2),all would contribute to the worse prognosis,although

many were not statistically signi ?cant in multivariate analysis (Table 3).Therefore,those patients who were treated with post-operative adjuvant therapy might have more badly pathological risk factors than those patients without adjuvant therapy.Table 2con ?rmed this ?nding.Among these pathological risk factors,the presence of lymph node metastases either in the pelvis or para-aortic area was statistically signi ?cantly frequently found in pa-tients who were treated with adjuvant therapy.These ?ndings might explain why these patients after adjuvant therapy still had a worse outcome (Fig.3).

Multivariate analysis showed that large pathological tumor size (HR 10.66,95%CI 2.93e 38.80),the presence of para-aortic lymph node metastases,and an immediate complication (HR 8.33and 4.55,95%CI 1.66e 41.75and 1.35e 15.27,respectively)contributed to a worse outcome (Table 3).Discussion

In our database,60of 689patients (8.7%)undergoing RH within the study period received the diagnosis of Cx-SCC https://www.wendangku.net/doc/6115531080.html,pared to those with smaller tumors at the same stage,early-stage bulky Cx-SCC has long been recognized as high risk,because of the high recurrence rate and worse prognosis [3].Many strategies have been used in an attempt to improve the prognosis and/or survival,especially for those patients who were treated mainly with surgery.The role of NACT in markedly bulky Cx-SCC was evaluated in this study.In agreement with the aforemen-tioned reports,the OS rate of all patients,whether or not NACT was used,was 58.3%.

This rate was inferior to the OS of those patients with FIGO IB Cx-SCC or conventionally de ?ned FIGO IB2(a cut value of the tumor size 4-cm Cx-SCC)who were treated with RH and PLND as the primary treatment in our hospital,because the 5-year OS rate ranged from 78%to 92%during different study periods [17e 19,22,24].

Compared with recent studies on NACT [7,9e 16],the main dif-ference in this study was the use of a single agent d cisplatin high-dose density CT (50mg/m 2)d with a very short interval before surgery (18days in our study),even though this dose seemed to

Fig.1.Overall survival (OS)of all patients with bulky squamous cell carcinoma of the cervix ( 6cm)undergoing primary treatment with either three courses of weekly cisplatin neoadjuvant therapy and radical hysterectomy (NACT-RH)or direct radical hysterectomy (RH).The OS rate of all patients was 58.3%,that of the NACT-RH group was 62.9%,and that of the RH group was 52%.p ?0.512.

Table 1

Clinical characteristics of patients with bulky-sized squamous cell carcinoma of the cervix.

Characteristics

NACT tRH n ?35(%)RH

n ?25(%)p Age (y)

48.9±9.350.5±7.60.476Image size (cm)

6.4±0.5 6.2±0.50.234Pathological size (cm) 4.5±1.4 5.7±0.8<0.001Estimated blood loss (mL)

558±1328930±356<0.001Number of pelvic LN metastasis 1.6±2.6 1.4±2.80.791Number of removed pelvic LN

23.5±5.026.3±6.60.072Number of para e aortic LN metastases 0.4±1.00.24±0.70.500Number of removed para e aortic LN 2.6±1.7 3.3±2.10.158Cell grade

Good-to-moderate differentiation 30(85.7%)21(84.0%)0.944Poor differentiation 5(14.3%)4(16.0%)DSI (yes)31(88.6%)23(92.0%)0.663LVSI (yes)

22(62.9%)16(64.0%)0.928Vaginal invasion (yes)5(14.3%)3(12.0%)0.797Parametrial invasion (yes)3(8.6%)2(8.0%)0.937Pelvic LN metastasis (yes)

13(37.1%)8(32.0%)0.681Para e aortic LN metastasis (yes)5(14.3%)3(12.0%)0.797Adjuvant therapy (yes)19(54.3%)16(64%)0.452Types of adjuvant therapy None 16(45.7%)9(36.0%)0.669

CCRT 6(17.1%)7(28.0%)CT 4(11.4%)4(16.0%)RT

9(25.7%)5(20.0%)Immediate complication (yes)2(5.7%)8(32.0%)0.007Late complication (yes)7(20.0%)8(32.0%)0.290Radiation-induced colitis 2(5.7%)4(16.0%)0.190Radiation-induced cystitis

4(11.4%)4(16.0%)0.608>12-mo ureter or urethra catheter use 3(8.6%)6(24.0%)0.099Recurrence of disease (yes)13(37.1%)12(48.0%)0.400Recurrence site None 22(62.9%)13(52.0%)0.846

Pelvis

1(2.9%)1(4.0%)Distant site 8(22.9%)8(32.0%)Both

4(11.4%)3(12.0%)Disease e free survival (mo)99.7±69.790.0±72.10.602Overall survival (mo)107.6±60.4104.0±60.20.821Died of disease (yes)

13(37.1%)

12(48.0%)

0.400

CCRT ?concurrent chemoradiation;CT ?chemotherapy;DSI ?deep stromal in-vasion;LN ?lymph node;LVSI ?lymphovascular space invasion;NACT ?neoadjuvant chemotherapy;RT ?radiation.

P.-H.Wang et al./Taiwanese Journal of Obstetrics &Gynecology 53(2014)330e 336

332

signi ?cantly lower than the frequently used dosage of 75mg/m 2[15].The concept that a shorter cycle length in combination with higher dose intensity tended to show an advantage for NACT was supported by a recent study [15].Mountzios et al [25]suggested that the interval between CT should not exceed 14days and the dose of cisplatin has to be greater than 25mg/m 2per week.This is important not only for surgery but also from a quality-of-life perspective (psychological aspect)[15].As mentioned previously,in theory,NACT provides bene ?ts not only during surgery but also postoperatively.NACT can reduce both tumor volume and

lymph

Fig.2.The following parameters are prognostic factors of the patients with bulky squamous cell carcinoma of the cervix ( 6cm)undergoing either three courses of weekly cisplatin neoadjuvant therapy and radical hysterectomy or direct radical hysterectomy:(A)pathological size ( 5.3cm vs.>5.3cm,p <0.001);(B)presence or absence of pelvic lymph node metastases (p <0.001);(C)presence or absence of para-aortic lymph node metastases (p <0.001);(D)presence or absence of immediate complication (p ?0.002);(E)presence or absence of late complication (p ?0.020);and (F)occurrence of recurrence (p ?0.004).LN meta ?lymph node metastasis;OS ?overall survival.

P.-H.Wang et al./Taiwanese Journal of Obstetrics &Gynecology 53(2014)330e 336333

node positivity,subsequently resulting in a decrease in the risk factors that indicate adjuvant RT [15].Reduction of tumor volume makes surgery easier (possibly less radical),especially parametrial resection,and thus,a reduction in the number of complications would be expected [26,27].In this study,NACT indeed signi ?cantly decreased the immediate complication rate,from 32%to 5.7%,although it did not statistically signi ?cantly decrease the need of postoperative adjuvant therapy (54.3%vs.64%,p ?0.452),which also contributed to the absence of a signi ?cant difference in disease-free survival and OS between the NACT-RH and RH groups,respectively (99.7±69.7months vs.90.0±72.1months,p ?0.602;107.6±60.4months vs.104.0±60.2months,p ?0.821,respec-tively).The reasons may be secondary to the study population,who were in a severe status,or the CT regimen itself [28].For example,the rate of lymph node metastases was higher in the study popu-lation than in patients classi ?ed as conventional FIGO IB (32e 37.1%vs.10e 18%).In addition,although tumor shrinkage was signi ?cant in the NACT e RH group (from 6.4±0.5cm to 4.5±1.4cm),the size of these tumors was still large ( 4cm).That is why the worse outcome could be related to the bulky tumor size ( 5.3cm.vs.>5.3cm with a HR of 10.66,p <0.001)and the presence of para-aortic lymph node metastases (HR 8.33,p ?0.010).

However,we still highlight the value of NACT in those patients with marked bulky Cx-SCC who were scheduled to undergo RH,because NACT indeed made surgery easier,with less blood loss (558±1328mL vs.930±356mL,p <0.001)and a lower immediate complication rate in this study.

All patients who experienced recurrence died of the disease,suggesting that conventionally postoperative radiation-based adjuvant therapy might not be affective in the management of these patients after NACT-RH or RH treatment.Although those patients who were treated with postoperative adjuvant therapy signi ?cantly had more unfavorable pathological risk factors,espe-cially presence of pelvic and/or para-aortic lymph node metastases (Table 2),the results of the current study were still consistent with those of our previous studies,showing any adjuvant therapy added little value for patients after RH or even though these patients had

Table 2

Clinical characteristics of patients with and without adjuvant therapy.Characteristics

No adjuvant treatment,n ?25(%)Adjuvant therapy,n ?35(%)p

Image size (cm)

6.2±0.4 6.5±0.60.017Pathological size (cm) 4.7±1.3 5.2±1.30.114Cell grade

Good-to-moderate differentiation

23(92.0%)28(80.0%)0.199

Poor differentiation 2(8.0%)7(20.0%)DSI (yes)24(96.0%)30(85.7%)0.190LVSI (yes)

17(68.0%)21(60.0%)0.526Vaginal invasion (yes)2(8.0%)6(17.1%)0.304Parametrial invasion (yes)1(4.0%)4(11.4%)0.305Pelvic LN metastasis (yes)0(0.0%)21(60.0%)<0.001Para-aortic LN

metastasis (yes)

0(0.0%)

8(22.9%)

0.010

DSI ?deep stromal invasion;LN ?lymph node;LVSI ?lymphovascular space invasion.

Table 3

Univariate and multivariate Cox regression analyses.Characteristics

Univariate analysis Multivariate analysis HR (95%CI)

HR (95%CI)p

Treatment RH 1(Ref)1(Ref)

NACT tRH 0.77(0.35e 1.69)0.5140.83(0.26e 2.65)0.753

Age (y) 501(Ref)1(Ref)

>50 1.05(0.48e 2.31)0.900 1.89(0.59e 6.06)0.282

Image size (cm) 61(Ref)1(Ref)

>6 1.67(0.75e 3.72)0.212 1.83(0.41e 5.32)0.546

Pathological size (cm) 5.31(Ref)1(Ref)

>5.3 5.45(2.32e 12.77)<0.00110.66(2.9e 38.80)<0.001

Blood loss (mL) 6501(Ref)1(Ref)

>650 1.62(0.74e 3.55)0.231 1.61(0.55e 4.76)

0.385

Number of removed pelvic LN 231(Ref)>230.58(0.27e 1.27)0.175

Number of removed para-aortic LN 31(Ref)>3 1.35(0.61e 3.00)0.466

Cell grade 11(Ref)2 1.63(0.22e 12.11)0.6343 1.18(0.12e 11.33)0.887

DSI No 1(Ref)1(Ref)

Yes 0.27(0.10e 0.73)0.0100.30(0.07e 1.37)0.121

LVSI No 1(Ref)1(Ref)

Yes 1.44(0.60e 3.45)0.414 1.07(0.25e 4.57)0.925

Vaginal invasion No 1(Ref)1(Ref)

Yes 0.53(0.13e 2.26)0.392 2.57(0.34e 19.77)0.364

Parametrial invasion No 1(Ref)1(Ref)

Yes 0.39(0.05e 2.87)0.3540.86(0.08e 9.63)0.903

Pelvic LN metastasis No 1(Ref)1(Ref)

Yes 4.41(1.97e 9.89)<0.001 2.76(0.68e 11.19)0.156

Para-aortic LN meta No 1(Ref)1(Ref)

Yes 4.99(2.12e 11.74)<0.0018.33(1.66e 41.75)0.010

Adjuvant therapy No 1(Ref)1(Ref)

Yes 2.93(1.17e 7.35)0.022 1.73(0.28e 10.87)

0.557

Types of adjuvant therapy None 1(Ref)CCRT 2.79(0.93e -8.31)

0.066

Table 3(continued )Characteristics

Univariate analysis Multivariate analysis HR (95%CI)

p HR (95%CI)

CT 4.81(1.5e 14.96)0.007

RT 2.21(0.71e 6.86)0.170

Immediate complication No 1(Ref)1(Ref)

Yes 3.74(1.60e 8.76)0.002 4.55(1.35e 15.27)0.014

Late complication No 1(Ref)1(Ref)

Yes 2.61(1.17e -5.83)0.020 1.31(0.31e 5.48)0.713

Radiation-induced colitis No 1(Ref)Yes 1.49(0.45e 4.98)0.519

Radiation-induced cystitis No 1(Ref)Yes 1.85(0.69e 4.95)

0.218

>12-mo ureter or urethra catheter use No 1(Ref)Yes 2.93(1.21e 7.08)0.017

Recurrence No 1(Ref)Yes 619.9(7.9e 48904)0.004

Recurrent site Nil 1(Ref)Pelvis 623997(0e 2.453E65)0.849Distant site 589728(0e 2.302E65)0.849Both sites 1860001(0e 7.2E65)

0.837

CCRT ?concurrent chemoradiation;CT ?chemotherapy;DSI ?deep stromal in-vasion;LN ?lymph node;LVSI ?lymphovascular space invasion;NACT ?neoadjuvant chemotherapy;R ?radiation.

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been treated with NACT,like patients with NACT-RH in the current study,if they were classi ?ed as a high-risk group based on the scoring system we proposed [1e 22].It was possible that the NACT regimen for these bulky-sized tumors needed a further investiga-tion,because three courses of weekly cisplatin 50mg/m 2might not provide an adequate or signi ?cant tumor reduction and tumor size was still the most strongly and signi ?cantly risk factor for worse outcome of patients with bulky-sized Cx-SCC.It was also possible that conventionally postoperative radiation-based adjuvant ther-apy (CCRT or RT)might not be a better choice for those high-risk patients.Most of these patients (77%,27/35)were treated with radiation-based adjuvant therapy (CCRT and RT)in the current study.By contrast,patients undergoing adjuvant therapy (who had worse pathologic risk factors)and patients without adjuvant therapy (who had less severe risk factors)had statistically similar survival in multivariate analysis,suggesting that adjuvant therapy might be bene ?cial to the patients in certain population who had worse pathologic risk factors,or chemotherapy could be considered as a postoperative adjuvant therapy,even though the role of chemotherapy is still uncertain for patients with Cx-SCC.Further-more,a more active and intensive surgical approach might be needed,although the role of surgical removal of the positive lymph nodes for patients with Cx-SCC is still controversial.In the current study,the mean number of retrieved para-aortic lymph nodes was

only three,and this might be relatively inadequate.A more extensive para-aortic lymphadenectomy to remove as many posi-tive lymph nodes as possible might provide additional information to schedule more effective therapies (systemic treatment),including clinical trials,because every effort should be conducted to minimize a subsequent distant failure.By contrast,the question d is more radical more effective?d [26]was raised,because patients with a long-term ureter or urethra catheter use (more than 12months after surgery)showed the worse prognosis.More trials are needed to determine how to balance the risks/bene ?ts of treatment for these patients with highly risky and bulky-sized Cx-SCC to provide an opportunity of better survival.

There are some limitations in the current study.First,this was a retrospective study,and selection bias inherent to the type of design may have been introduced in this study.The best way to avoid or minimize this bias is to conduct a prospective randomized study,but there should be a high number of patients enrolled to show a statistically signi ?cant difference [2].However,retrospec-tive study with large datasets is still the best way to investigate this issue.Second,the sample size of patients was small in this study.But it is not easy to enroll an adequate number of patients with Cx cancer,especially with markedly bulky tumors,such as in 6-cm Cx-SCC,because Cx cancer may become a relatively rare disease in some areas in the future,if a nationwide screening program and the introduction of human papilloma virus vaccination in the teenage population can be continued.Third,the diagnoses of late complications were only made by the patients'needs for medical care,but the severity was not graded.In addition,late complica-tions might not be totally revealed in the limited items,such as radiation colitis and cystitis,and long-term ureter or catheter use ( 12months).Despite these limitations,this is a relatively large study with a long-term follow-up to investigate the potential role of NACT in the management of patients with Cx-SCC 6-cm.

Finally,without a randomized study comparing NACT-RH with CCRT [15]or the signi ?cant bene ?ts of OS with a comparison of direct RH in this study,the choice of NACT-RH in the management of markedly bulky Cx-SCC,especially the use of three cycles of weekly 50mg/m 2cisplatin,would need further con ?rmation.However,we still believe that NACT is a feasible experimental treatment method,because in this study,we found a signi ?cant decrease in blood loss during operation,a decrease in the patho-logical tumor size and immediate complication rate.Con ?icts of interest

The authors have no con ?icts of interest relevant to this article.Acknowledgments

This work was supported by grants from the Ministry of Science and Technology,Executive Yuan (NSC 102-2314-B-010-032;NSC 99-2314-B-010-009-MY3;MOST 103-2314-B-010-043-MY3to P.-H.Wang),Taipei Veterans General Hospital (V102C-141;V103C-112;V102E4-003;V103E4-003to P.-H.Wang,and V103A-016to W.-H.Chang).The funders had no role in study design,data collection and analysis,decision to publish,or preparation of the manuscript.No additional external funding was received for this study.We also thank the Medical Science &Technology Building of Taipei Veterans General Hospital for providing experimental space and facilities.References

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风险管理工作步骤

第三要素：风险管理一、企业应组织制定风险评价管理制度，明确风险评价的目的、范围和准则。 1、建立风险评价管理制度。制度培训记录，人员熟悉情况。 2、风险评价范围包括：规划、设计和建设、投产、运行阶段；常规和非常规活动；事故及潜在的紧急情况；所有进入场所人员的活动；原材料、产品的运输和使用过程；作业场所的设施、设备、车辆、安全防护用品；丢弃、废弃、拆除与处置；企业周围的环境；气候、地震及其他自然灾害（查风险评价制度及风险评价记录）。二、企业可根据需要，选择科学、有效、可行的风险评价方法，包括：工作危害分析（JHA）对作业活动分析；安全检查表分析（SCL）对设备、设施进行危险、有害因素识别和风险评价；预危险性分析（PHA);危险与可操作性分析（HAZOP）对危险性工艺进行危险、有害因素识别和风险评价；失效模式与影响分析（FMEA);故障数分析（FTA）；事件数分析（ETA)；作业条件危险性分析（LEC)等方法。三、企业应以以下内容制定风险评价准则： 1、有关安全生产法律、法规。 2、设计规范、技术标准。 3、企业的安全管理标准、技术标准。

4、企业的安全生产目标及方针等。 5、风险评价涉及的事件发生可能性、严重性的取值标准或风险等级评定标准必须明确。四、企业应依据风险评价准则，选定合适的评价方法，定期和及时对作业活动和设备设施进行危险、有害因素识别和风险评价。企业在进行风险评价时，应从影响人、财产和环境等三个方面的可能性和严重程度分析。 1、建立作业活动清单、设备、设施清单； 2、风险评价记录、风险评价报告。 3、企业各级管理人员应参与风险评价工作，鼓励从业人员积极参与风险评价和风险控制工作。 ①厂级评价组织应有企业负责人参加；成立风险评价小组文件；风险分析记录及风险评价报告；风险评价会议纪要；询问企业主要负责人是否参与风险评价工作。 ②车间级评价组织应有车间负责人参加； ③所有从业人员应参与风险评价和风险控制。五、企业应根据风险评价结果及经营运行情况等，确定不可接受的风险，制定并落实控制措施，将风险尤其是重大风险控制在可以接受的程度。企业在选择风险控制措施时应考虑：可行性；安全性；可靠性。应包括：工程技术措施；管理措施；培训教育措施；个体防护措施。 1、建立重大风险源清单。

销售与收款流程风险控制及流程图

销售与收款流程风险控制及流程图 -标准化文件发布号：（9456-EUATWK-MWUB-WUNN-INNUL-DDQTY-KII

销售与收款业务流程一.业务目标 1.经营目标通过规范销售与收款业务流程，确保产品销售与收款业务按规定程序和适当授权进行，实现预期经营目标。 2.财务目标确保销售与收款业务及相关会计科目的核算真实、完整、规范，防止差错和舞弊，保证财务报表合理揭示业务发生的折扣和折让。 3.合规目标保证销售业务及其税金的处理符合国家相关法律法规及公司的规定。二、业务风险 1.经营风险由于产品销售与收款业务流程设计不合理或控制不当，可能导致产品销售及价格、信用政策等与目标要求不一致，或出现舞弊和差错。 2.财务风险

可能导致会计核算多记、少（漏）记或错记销售收入、应收账款及其他相关会计事项，造成核算和反映不真实、不准确、不完整。 3.合规风险可能导致销售业务违反国家有关规定而受到行政处罚和法律制裁。三、业务流程步与控制点 1.受理订单与编制销售计划（1）销售部门分析客户需求，受理客户订单，订单应按类别连续编号。 ※（2）所有订单均由被授权人核准，并对客户信用状况进行初步核查。销售部门依据客户信用状况及订单和生产计划、库存等情况，编制销售产品的品种、规格型号、数量、价格、货款支付方式等具体的销售计划与赊销方案，并经部门领导审核签字。 2.审定销售方案和信用政策 ※（1）产品销售计划传送给分公司分管业务的领导审定，特别重大的产品销售计划报公司总经理办公会审定。销售产品拟采用赊销方式的应对客户信用进行审核。销售部门应根据本部门已掌握或客户提供的信用资料，结合产品销

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挖掘机节能液压控制系统分析与应用? 李艳杰 1,2于安才 2姜继海 2 (1. 沈阳理工大学机械工程学院沈阳 110159; 2. 哈尔滨工业大学机电工程学院哈尔滨 150001 摘要 :深入分析了现代液压挖掘机中三种主流的节能液压系统——负流量控制、正流量控制和负载敏感系统的基本工作原理, 重点分析了它们在不同系列挖掘机中的应用;介绍了两种新型挖掘机液压系统的基本原理;分析表明三种典型挖掘节能液压系统都具有一定的节能效果,但工作原理各有不同;新型的挖掘机液压系统虽然还在研发阶段,但具有更好的节能效果及应用前景。关键词:液压挖掘机负流量控制正流量控制负载敏感系统中图分类号 TU621 Analyses and Application of Energy-Saving Hydraulic Control System of Excavator LI Yan-jie1,2YU an-cai2JIANG Ji-hai2 (1. School of Mechanical Engineering, Shenyang Ligong University, Shenyang 110159; 2. School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001 Abstract : Negative flow control, positive flow control and load sensing are the general energy-saving hydraulic systems of modern hydraulic excavator. The basic principles of the three typical hydraulic control systems were analyzed deeply. Their application in different kind of excavators is mainly analyzed. The principles of two new

第86讲_风险管理基本流程

第六章风险与风险管理风险管理基本流程收集风险管理初始信息（★★）分析战略风险（1）国内外宏观经济政策以及经济运行情况、企业所在产业的状况、国家产业政策；（2）科技进步、技术创新的有关内容；（3）市场对该企业产品或服务的需求；（4）与企业战略合作伙伴的关系，未来寻求战略合作伙伴的可能性；（5）该企业主要客户、供应商及竞争对手的有关情况；（6）与主要竞争对手相比，该企业实力与差距；（7）本企业发展战略和规划、投融资计划、年度经营目标、经营战略，以及编制这些战略、规划、计划、目标的有关依据；（8）该企业对外投融资流程中曾发生或易发生错误的业务流程或环节。分析财务风险（1）负债、或有负债、负债率、偿债能力；（2）现金流、应收账款及其占销售收入的比重、资金周转率；（3）产品存货及其占销售成本的比重、应付账款及其占购货额的比重；（4）制造成本和管理费用、财务费用、营业费用；（5）盈利能力；（6）成本核算、资金结算和现金管理业务中曾发生或易发生错误的业务流程或环节；（7）与本企业相关的产业会计政策、会计估算、与国际会计制度的差异与调节（如退休金、递延税项等）等信息。分析市场风险

外宏观经济政策以及经济运行情况、企业所在产业的状况、国家产业政策；②科技进步、技术创新的有关内容； ③市场对该企业产品或服务的需求；④与企业战略合作伙伴的关系，未来寻求战略合作伙伴的可能性；⑤该企业主要客户、供应商及竞争对手的有关情况；⑥与主要竞争对手相比，该企业实力与差距；⑦本企业发展战略和规划、投融资计划、年度经营目标、经营战略，以及编制这些战略、规划、计划、目标的有关依据；⑧该企业对外投融资流程中曾发生或易发生错误的业务流程或环节。进行风险评估（★）进行风险评估的方法（1）进行风险辨识、分析和评价，应将定性与定量方法相结合。（2）定性方法可采用问卷调查、集体讨论、专家咨询、情景分析、政策分析、行业标杆比较、管理层访谈、由专人主持的工作访谈和调查研究等。定量方法可采用统计推论（如集中趋势法）、计算机模拟（如蒙特卡洛分析法）、失效模式与影响分析、事件树分析等。（3）进行风险定量评估时，应统一制定各风险的度量单位和风险度量模型。（4）要根据环境的变化，定期对假设前提和参数进行复核和修改，并将定量评估系统的估算结果与实际结果对比，据此对有关参数进行调整和改进。（5）企业在评估多项风险时，应根据对风险发生可能性的高低和对目标的影响程度的评估，绘制风险坐标图，对各项风险进行比较，初步确定对各项风险的管理优先顺序和策略。（6）风险评价应由企业组织有关职能部门和业务单位实施，也可聘请有资质、信誉好、风险管理专业能力强的中介机构协助实施。（7）企业应对风险管理信息实行动态管理，定期或不定期实施风险辨识、分析、评价，以便对新的风险和原有风险的变化重新评估。近五年知识点考情分析 20182017201620152014 风险评估无无多选无无试题精讲【多选】下列各项关于风险评估的表述中，正确的有（）。（2016年） A.风险评估包括风险辨识、风险分析和风险评价三个步骤 B.风险定性评估时应统一制定各风险的度量单位和度量模型 C.企业应当定期或不定期对新风险或原有风险的变化进行重新评估 D.风险评估应当将定性方法和定量方法相结合【答案】ACD 【解析】风险评估包括风险辨识、风险分析、风险评价三个步骤，所以，选项A正确；进行风险定量评估时，应统一制定各风险的度量单位和风险度量模型，所以，选项B错误；企业应对风险管理信息实行动态管理，定期或不定期实施风险辨识、分析、评价，以便对新的风险和原有风险的变化重新评估，所以，选项C正确；进行风险辨识、分析、评价，应将定性与定量方法相结合，所以，选项D正确。制定风险管理策略（★）风险管理策略是指企业根据自身条件和外部环境，围绕企业发展战略，确定风险偏好、风险承受度、风险管理有效性标准，选择风险承担、风险规避、风险转

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浅论挖掘机液压系统故障分析及解决措施示范文本 In The Actual Work Production Management, In Order To Ensure The Smooth Progress Of The Process, And Consider The Relationship Between Each Link, The Specific Requirements Of Each Link To Achieve Risk Control And Planning 某某管理中心 XX年XX月

浅论挖掘机液压系统故障分析及解决措施示范文本使用指引：此解决方案资料应用在实际工作生产管理中为了保障过程顺利推进，同时考虑各个环节之间的关系，每个环节实现的具体要求而进行的风险控制与规划，并将危害降低到最小，文档经过下载可进行自定义修改，请根据实际需求进行调整与使用。一、引言液压系统是工程机械中的一个重要部分。液压系统由于具有体积小、重量轻、易安装、功率密度大、响应快、可控制性强、工作平稳且可实现大范围的无级调速等优点。应用日趋广泛。液压挖掘机是目前工程施工中使用较为广泛的一种工程机械，其行走、回转和举升、挖掘动作都是通过发动机把机械能转化为液压油的压力能来驱动液压油缸和马达工作而实现的。对于液压系统。虽然只是作为挖掘机复杂主系统的子系统，但是其对主系统的功能和效率产生的影响是巨大的。液压系统的失效将会直接导致主系统的失效，从而造成严重的经济损失。因此，对液压

挖掘机液压系统的分析及故障诊断尤为重要。二、挖掘机的液压系统类型按液压栗特性，液压挖掘饥采用的液压系统大致上有定量系统、变量系统和定量、变量系统等三种类型。 (一)定量系统在液压挖掘机采用的定量系统中，其流量不变，即流量不随负载而变化，通常依靠节流来调节速度。根据定量系统中油泵和回路的数量及组合形式，分为单泵单回路、双泵单回路定量系统、双泵双回路定量系统及多泵多回路定量系统等。 (二）变量系统在液压挖掘机采用的变量系统中，是通过容积变量来实现无级调速的，其调节方式有三种：变量泵一定量马达调速、定量泵变量马达调速、变量泵变量马达调速。液压挖掘机采用的变量系统多采用变量泵一定量马达的组合方

电源电动势与电压的关系

电源电动势与电压的关系一、电动势是反映电源把其他形式的能转换成电能的本领的物理量。电动势使电源两端产生电压。在电路中，电动势常用E 表示。单位是伏（V）。在电源内部，非静电力把正电荷从负极板移到正极板时要对电荷做功，这个做功的物理过程是产生电源电动势的本质。非静电力所做的功，反映了其他形式的能量有多少变成了电能。因此在电源内部，非静电力做功的过程是能量相互转化的过程。电动势的大小等于非静电力把单位正电荷从电源的负极，经过电源内部移到电源正极所作的功。如设W为电源中非静电力（电源力）把正电荷量q从负极经过电源内部移送到电源正极所作的功跟被移送的电荷量的比值，则电动势大小为：。如：电动势为6伏说明电源把1库正电荷从负极经内电路移动到正极时非静电力做功6焦。有6焦的其他其形式能转换为电能。电动势的方向规定为从电源的负极经过电源内部指向电源的正极，即与电源两端电压的方向相反。二、电压（voltage），也称作电势差或电位差，是衡量单位电荷在静电场中由于电势不同所产生的能量差的物理量。其大小等于单位正电荷因受电场力作用从A点移动到B点所

做的功，电压的方向规定为从高电位指向低电位的方向。电压的国际单位制为伏特（V，简称伏），常用的单位还有毫伏（mV）、微伏（μV）、千伏（kV）等。此概念与水位高低所造成的“水压”相似。需要指出的是，“电压”一词一般只用于电路当中，“电势差”和“电位差”则普遍应用于一切电现象当中。电压是电路中自由电荷定向移动形成电流的原因。电势差（电压差）的定义：电荷q 在电场中从A点移动到B点，电场力所做的功 W AB与电荷量q 的比值，叫做AB两点间的电势差（AB两点间的电势之差，也称为电位差），用U AB表示，则有公式：其中，W AB为电场力所做的功，q为电荷量。同时也可以利用电势这样定义如果电压的大小及方向都不随时间变化，则称之为稳恒电压或恒定电压，简称为直流电压，用大写字母U表示。如果电压的大小及方向随时间变化，则称为变动电压。对电路分析来说，一种最为重要的变动电压是正弦交流电压(简称交流电压)，其大小及方向均随时间按正弦规律作周期性变化。交流电压的瞬时值要用小写字母u或u(t)表示。在电路中提供电压的装置是电源。

案例分析挖掘机液压系统发热故障及预防措施实用版

YF-ED-J8528 可按资料类型定义编号案例分析挖掘机液压系统发热故障及预防措施实用版 In Order To Ensure The Effective And Safe Operation Of The Department Work Or Production, Relevant Personnel Shall Follow The Procedures In Handling Business Or Operating Equipment. （示范文稿）二零XX年XX月XX日

案例分析挖掘机液压系统发热故障及预防措施实用版提示：该解决方案文档适合使用于从目的、要求、方式、方法、进度等都部署具体、周密，并有很强可操作性的计划，在进行中紧扣进度，实现最大程度完成与接近最初目标。下载后可以对文件进行定制修改，请根据实际需要调整使用。挖掘机液压系统发热是机械故障的一个普遍现象，我们必须要知道，这一现象会给挖掘机系统带来怎样的危害，其故障特征表现为那些。本文将以实例来分析讲解。在施工现场，工程机械故障的事情是时有发生，比如：我们正操作挖掘机，发现其液压系统有发热现象，液压系统发热必须要及时处理，否则会给挖掘机整个系统带来危害，下面我们共同来了解一下挖掘机液压系统发热现象及其危害，并以实例来作以分析。

一、了解挖掘机液压系统发热现象及其危害：液压系统发热是挖掘机较为普遍的一种故障现象，亦是分析处理较为复杂的软故障。小松PC200/400型挖掘机正常工况下，液压系统油温应在60oC以下，（油泵的温度较之高5-10oC），如果超出较多，则称之为液压系统发热。其故障特征为：挖掘机冷车工作是，各种动作较正常，当机械工作约一小时后，随着液压油温升高，便出现挖掘机各执行机构无力及动作滞缓，特别是挖掘力不够，行走转向困难等。液压系统出现发热现象如不能及时处理，就会对系统产生极为不利的影响：（1）油液粘度下降，泄漏增加，又使系统

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YF-ED-J3481 可按资料类型定义编号液压式履带挖掘机液压系统故障分析实用版 In Order To Ensure The Effective And Safe Operation Of The Department Work Or Production, Relevant Personnel Shall Follow The Procedures In Handling Business Or Operating Equipment. （示范文稿）二零XX年XX月XX日

液压式履带挖掘机液压系统故障分析实用版提示：该解决方案文档适合使用于从目的、要求、方式、方法、进度等都部署具体、周密，并有很强可操作性的计划，在进行中紧扣进度，实现最大程度完成与接近最初目标。下载后可以对文件进行定制修改，请根据实际需要调整使用。结合多年的实践经验，笔者对液压式履带挖掘机液压系统常见故障进行了分析，主要包括有液压油温度过高、液压油管爆裂和油管接头漏油、行走跑偏、整机无动作、整机动作无力等故障，并给出了排除方法，可供相关专业技术人员参考。当前国内大部分的挖掘机都是液压式履带类型，采用的是液压先导式控制系统。虽然液压挖掘机生产厂家不同，但是其液压系统却基本差不多，都是由先导液压系统和主液压系

统两大部分构成。如果回转和行走采用液压马达驱动，工作装置通过油缸执行其动作，这类挖掘机就是全液压挖掘机。全液压挖掘机的液压系统是一个有机的整体，无论哪个元件出了故障，都会影响其正常工作。现以山河智能液压式履带挖掘机为例，分析液压系统常见故障原因及排除方法。液压油温度过高当液压油温度过高时，就必须考虑是否出现以下状况。 1.1.发动机皮带松动这种情况下，挖掘机显示器会显示充电故障及高温。在熄火状态下用手去按动皮带，感受发动机皮带的松紧程度。由于皮带长期处于高速运动中，会逐渐老化，发动机启动

挖掘机液压系统图

挖掘机液压系统图一．液压挖掘机液压系统的基本类型液压挖掘机液压系统大致上有定量系统、变量系统和定量、变量复合系统等三种类型。 1．定量系统在液压挖掘机采用的定量系统中，其流量不变，即流量不随外载荷而变化，通常依靠节流来调节速度。根据定量系统中油泵和回路的数量及组合形式，分为单泵单回路定量系统、双泵单回路定量系统、双泵双回路定量系统及多泵多回路定量系统等。 2．变量系统在液压挖掘机采用的变量系统中，是通过容积变量来实现无级调速的，其调速方式有三种：变量泵－定量马达调速、定量泵－变量马达调速和变量泵－变量马达调速。单斗液压挖掘机的变量系统多采用变量泵－定量马达的组合方式实现无极变量，且都是双泵双回路。根据两个回路的变量有无关连，分为功率变量系统和全功率变量系统两种。其中的分功率变量系统的每个油泵各有一个功率调节机构，油泵的流量变化只受自身所在回路压力变化的影响，与另一回路的压力变化无关，即两个回路的油泵各自独立地进行恒功率调节变量，两个油泵各自拥有一半发动机输出功率；全功率变量系统中的两个油泵由一个总功率调节机构进行平衡调节，使两个油泵的摆角始终相同。同步变量、流量相等。决定流量变化的是系统的总压力，两个油泵的功率在变量范围内是不相同的。其调节机构有机械联动式和液压联动式两种形式。二．YW-100型单斗液压挖掘机液压系统国产YW-100型履带式单斗液压挖掘机的工作装置、行走机构、回转装置等均采用液压驱动，其液压系统如图1所示。该挖掘机液压系统采用双泵双向回路定量系统，由两个独立的回路组成。所用的油泵1为双联泵，分为A、B两泵。八联多路换向阀分为两组，每组中的四联换向阀组为串联油路。油泵A输的压力进入第一组多路换向阀，驱动回转马达、铲斗油缸、辅助油缸，并经中央回转接头驱动右行走马达7。该组执行元件不工作时油泵A输出的压力油经第一组多路换向阀中的合流阀进入第二组多路换向阀，以加快动臂或斗杆的工作速度。油泵B输出的压力油进入第二组多路换向阀，驱动动臂油缸、斗杆油缸，并经中央回转接头驱动左行走马达8和推土板油缸6。该液压系统中两组多种换向阀均采用串联油路，其回油路并联，油液通过第二组多路换向阀中的限速阀5流向油箱。限速阀的液控口作用着由梭阀提供的A、B两油泵的最大压力，当挖掘机下坡行走出现超速情况时，油泵出口压力降低，限速阀自动对回油进行节流，防止溜坡现象，保证挖掘机行驶安全。

风险管理基本流程

高顿财经CPA 培训中心 1 风险管理基本流程收集风险管理初始信息风险管理基本流程的第一步，要广泛地、持续不断地收集与本企业风险和风险管理相关的内部、外部初始信息，包括历史数据和未来预测。应把收集初始信息的职责分工落实到各有关职能部门和业务单位。收集初始信息要根据所分析的风险类型具体展开。例如： (一)分析战略风险，企业应广泛收集国内外企业战略风险失控导致企业蒙受损失的案例，并至少收集与本企业相关的以下重要信息： 1.国内外宏观经济政策以及经济运行情况、企业所在产业的状况、国家产业政策; 2.科技进步、技术创新的有关内容; 3.市场对该企业产品或服务的需求; 4.与企业战略合作伙伴的关系，未来寻求战略合作伙伴的可能性; 5.该企业主要客户、供应商及竞争对手的有关情况; 6.与主要竞争对手相比，该企业实力与差距; 7.本企业发展战略和规划、投融资计划、年度经营目标、经营战略，以及编制这些战略、规划、计划、目标的有关依据; 8.该企业对外投融资流程中曾发生或易发生错误的业务流程或环节。 (二)分析财务风险，企业应广泛收集国内外企业财务风险失控导致危机的案例，并至少收集本企业的以下重要信息： 1.负债、或有负债、负债率、偿债能力; 2.现金流、应收账款及其占销售收入的比重、资金周转率; 3.产品存货及其占销售成本的比重、应付账款及其占购货额的比重; 4.制造成本和管理费用、财务费用、营业费用; 5.盈利能力;

高顿财经CPA 培训中心 2 6.成本核算、资金结算和现金管理业务中曾发生或易发生错误的业务流程或环节; 7.与本企业相关的产业会计政策、会计估算、与国际会计制度的差异与调节(如退休金、递延税项等)等信息。 (三)分析市场风险，企业应广泛收集国内外企业忽视市场风险、缺乏应对措施导致企业蒙受损失的案例，并至少收集与该企业相关的以下重要信息: 1.产品或服务的价格及供需变化; 2.能源、原材料、配件等物资供应的充足性、稳定性和价格变化; 3.主要客户、主要供应商的信用情况; 4.税收政策和利率、汇率、股票价格指数的变化; 5.潜在竞争者、竞争者及其主要产品、替代品情况。 (四)分析运营风险，企业应至少收集与本企业、本产业相关的以下信息： 1.产品结构、新产品研发; 2.新市场开发，市场营销策略，包括产品或服务定价与销售渠道，市场营销环境状况等; 3.企业组织效能、管理现状、企业文化，高、中层管理人员和重要业务流程中专业人员的知识结构、专业经验; 4.期货等衍生产品业务中曾发生或易发生失误的流程和环节; 5.质量、安全、环保、信息安全等管理中曾发生或易发生失误的业务流程或环节; 6.因企业内、外部人员的道德风险致使企业遭受损失或业务控制系统失灵; 7.给企业造成损失的自然灾害以及除上述有关情形之外的其他纯粹风险; 8.对现有业务流程和信息系统操作运行情况的监管、运行评价及持续改进能力; 9.企业风险管理的现状和能力。 (五)分析法律风险方面，企业应广泛收集国内外企业忽视法律法规风险、缺乏应对措施导致企业蒙受损失的案例，并至少收集与该企业相关的以下信息： 1.国内外与该企业相关的政治、法律环境;

企业内部控制流程梳理与风险识别

企业内部控制流程梳理与风险识别主讲：赵玉梅目录一、认识内控流程二、认识风险识别三、如何建立与改进一、认识内控流程（一）案例——典型内控事件（二）内部控制的概念（三）内控问题及产生原因（一）案例——典型内控事件：安然公司(Enron Corporation)：原是世界上最大的综合性天然气和电力公司之一，在北美地区是头号天然气和电力批发销售商。辉煌业绩：世界最大的能源公司，500强排名第7，曾被称为“美国最有创新精神的公司”。严重问题：（1）2001年末，安然宣布第三季度亏损6.4亿美元。美国证监会进行调查，发现该公司1997以来虚报利润5.8亿美元。（2）2001年末安然申请破产保护。在之前10个月内，公司因股票价格超越预期目标而向董事及高级管理人员发放3.2亿美元的红利。（3）2006，安然主席及CEO被美国法院认定有罪，前创始人受多项指控，其中4项银行欺诈罪将导致最高120年监禁的判决；前CEO受19项指控最终判24年监禁；CFO也被判刑10年。（4）半年多时间，股市市值缩水2.5万亿美元；安然公司破产直接导致美国金融机构损失200亿美元。深层原因：（1）会计舞弊：通过财务作假和滥用会计方法，隐瞒亏损，掩盖债务和巨大的交易风险（1997以来虚报利润5.8亿美元），误导投资人以牟取私利。（2）业务集中：业务集中在“能源衍生品交易”，公司出现任何信用风险后，带来一连串灾难性后果，造成现金流困难。（3）恶性扩张：追求“管理创新”，自封“世界领先公司”，业务不断扩张，从天然气、电力业务，到风力、水力、投资、木材、广告、互联网宽带业务等，无所不包。风险事件的反思：（1）安然、世通、施乐、安达信等公司欺诈，会计造假丑闻使投资大众遭受巨大的损失。（2）中航油（新加坡）违规操作被判刑并罚款，巴林银行由于私自交易被1英镑价格交易。（3）在2000年至2002年期间，由于在美国发生的涉及巨型公司财务丑闻，导致资本市场损失了7万亿美金的市值。（4）诚信危机震撼着美国及国际社会，美国企业的假账丑闻一时间成为全球舆论的焦点。强化内部控制是有效防范风险的重要手段：（1）知名企业失败案例与内部控制缺陷密切相关；（2）内部控制能够做到事前防范，及时发现苗头并予以补救。（二）内部控制的概念内部控制是由企业董事会、监事会、经理层和全体员工实施的、旨在实现控制目标的过程。

挖掘机液压系统设计

目录绪论----------------------------------------3 1.1现代液压技术的发展状况---------------4 1.2液压传动的研究对象-------------------4 1.3液压传动的组成-----------------------4 1.4液压传动的优缺点---------------------5 1.3.1液压传动的主要优点------------------5 1.3.2 液压传动的主要缺点------------------5 1.5液压技术的发展应用-------------------6 1.4.1、液压传动在各类机械中的应用---------6 1.4.2、液压传动技术的发展概况-------------7 第1章挖掘机的液压系统----------------------8 2.1挖掘机的工作循环及对液压系统的要求-----8 2.2 WY—100挖掘机液压系统的工作原理-------9 第3章液压系统的设计-----------------------12 3.1明确设计要求进行工况分析---------------12 3.2确定液压系统的主要参数-----------------13 3.2.1液压缸的载荷组成计算-----------------13 3.2.2液压马达的负载-----------------------15 3.3计算液压缸的主要结构尺寸和液压马达的排 ---------------------------------------15 3.3.1液压缸的设计计算---------------------15 3.3.2液压马达的设计计算-------------------16 3.4液压泵的确定与所需功率的计算-----------17 3.4.1液压泵的确定-------------------------17 3.4.2 选择液压泵的规格--------------------18 3.5阀类元件的选择-------------------------18 3.5.1.选择依据----------------------------18