中国实验快堆1台一回路泵切除试验计算模拟与分析

为检验中国实验快堆(CEFR)发生1台一回路泵切除事件时的安全性,拟在CEFR上进行试验验证。为确保试验的安全性,利用系统分析程序OASIS对试验过程进行了模拟,并对试验可能存在的风险进行了分析。计算结果表明:按照试验步骤进行操作不会对反应堆安全构成威胁;试验初期存在一些风险,源于主热传输系统各回路的流量不匹配问题,可能会对设备产生较大的热冲击。

国产200MW机组切除高压加热器带最大负荷的试验研究

本文介绍了在秦岭电厂5号机组上所进行的热力性能试验和分析,并探讨了国产200MW机组在切除高压加热器后带最大负荷的安全性和经济性分析,分析结果可供同类型机组在运行及技术改造时参考。

腹腔镜辅助阴式子宫切除术对卵巢近远期功能的影响

目的:了解腹腔镜辅助阴式子宫切除术对卵巢近远期内分泌的影响。方法:对67例50岁以下的非绝经期妇女因妇科良性疾病,有子宫切除指征的患者行腹腔镜辅助阴式子宫切除术(LAVH),分别在术前、术后1、6、12、24个月测定血P、T、E2、FSH、LH水平。结果:腹腔镜辅助阴式子宫切除术后血E2、FSH、LH水平近期无变化,远期则E2下降明显,FSH、LH升高。结论:腹腔镜辅助阴式子宫切除术对卵巢近期功能影响不明显,远期功能则有一定影响。

吲哚氰绿(ICG)排泄试验和MELD评分

目的探讨吲哚氰绿(ICG)排泄试验和MELD评分之间的关系。方法40例终末期肝病患者,根据Child-Pugh肝功能分级分为A、B、C三级;利用脉冲式色素浓度图象分析仪(DDG)行吲哚氰绿(ICG)排泄试验(血浆清除率(K)和15分钟滞留率(R15),同时计算患者的终末期肝病模型(MELD)评分。结果随着肝功能分级的递增,K值下降,而R15和MELD评分则增加,各级之间相比差异有统计学意义;吲哚氰绿(ICG)排泄试验与MELD评分之间有显著的相关性,K值与MELD评分呈明显负相关(r=-0.901);而R15与MELD评分则成明显正相关(r=0.864)。结论1.吲哚氰绿(ICG)排泄试验(K值、R15)是评价肝脏储备功能的良好指标,其K值、R15随着Child-Pugh肝功能分级的递增而变化;2.K值和R15与MELD评分关系密切,其中,K值的相关性更为显著,提示K值有可能成为评估终末期肝病简便、准确的指标。

10kV高压开关柜交流耐压试验故障的排除

1 故障现象 2005年8月，我公司制造的10kV高压开关柜（KYN44型）安装完毕后（未接避雷器），对进线柜（编号为G1）进行交流耐压试验。当电压升至25kV时，高压传感器信号灯三相均灭；继续升压至42kV，开关柜内放电严重。切除试验电源检查，未见异常。将试验电源从零开始再次升高电压，此时显示装置一直不亮。

小菜蛾触角的显微结构及其作用

采用扫描电镜观察小菜蛾触角 ,发现雄蛾有 9种感觉器 ,雌蛾有 8种感觉器 .触角切除试验表明 ,触角是小菜蛾重要的感觉器官 。

磁共振血管造影与数字减影血管造影在脑血管狭窄闭塞性疾病诊断中的比较研究(英文)

目的:对比研究磁共振血管造影(MRA)(1.5、3.0 T)与数字减影血管造影(DSA)对于脑血管狭窄闭塞性疾病诊断及量化的作用。方法:回顾性研究110例临床怀疑患有脑血管病变的受试病人,其中55例行1.5 T MRA扫描(3D TOF序列),另55例行3.0 T MRA(3D TOF序列)扫描。在最大密度投影重建像及常规DSA图像下测定脑血管狭窄程度,以北美有症状颈动脉内膜切除试验标准为参考。结果:对于脑血管狭窄的分级,1.5 T、3.0 T MRA与DSA结果一致率分别为86.5%、90.5%。在诊断明确后,1.5 T MRA敏感度及特异度分别为90%、98%;阳性预测值(PPV)及阴性预测值(NPV)分别为87%、99%;总准确率为94%。同时,3.0 T MRA敏感度及特异度分别为92%、99%,PPV及NPV分别为91%、99%,准确率为96%。对于脑血管狭窄闭塞疾病的测定,DSA与1.5 T MRA(P=0.31)、3.0 T MRA(P=0.30)差异均无统计学意义,1.5 T MRA与3.0 T MRA之间差异亦无统计学意义(P=0.70)。结论:本实验结果表明,对于脑血管狭窄闭塞性疾病的诊断MRA的3 D TOF序列能够作为DSA之外的一种可靠的诊断方法,且3.0 T MRA稍优于1.5 T MRA。

Prospective randomized controlled trial investigating the type of sutures used during hepatectomy

AIM: To determine whether absorbable sutures or non-absorbable sutures are better in preventing surgical site infection (SSI), in this paper we discuss the results of a randomized clinical trial which examined the type of sutures used during hepatectomy. METHODS: All hepatic resections performed from January 2007 to November 2008 at the Department of Surgery at Iizuka Hospital in Japan were included in this study. There were 125 patients randomly assigned to an absorbable sutures (Vicryl) group or non-absorbable sutures (Silk) group. RESULTS: SSI was observed in 13.6% (17/125) patients participating in this study, 11.3% in the Vicryl group and 15.8% in the Silk group. Incisional SSI including superficial and deep SSI, was observed in 8% of the Vicryl group and 9.5% of the Silk group. Organ/ space SSI was observed in 3.2% of the Vicryl group and 6.0% of the Silk group. There were no significant differences, but among the patients with SSI, the period for recovery was significantly shorter for the Vicryl group compared to the Silk group.CONCLUSION: The incidence of SSI in patients receiving absorbable sutures and silk sutures is not significantly different in this randomized controlled study; however, the period for recovery in patients with SSI was significantly shorter for absorbable sutures.

Current concepts in hepatic resection for hepatocellular carcinoma in cirrhotic patients

Hepatocellular carcinoma(HCC) is one of the most frequent neoplasms worldwide and in most cases it is associated with liver cirrhosis.Liver resection is considered the most potentially curative therapy for HCC patients when liver transplantation is not an option or is not immediately accessible.This review is aimed at investigating the current concepts that drive the surgical choice in the treatment of HCC in cirrhotic patients;Eastern and Western perspectives are highlighted.An extensive literature review of the last two decades was performed,on topics covering various aspects of hepatic resection.Early post-operative and long-term outcome measures adopted were firstly analyzed in an attempt to define an optimal standardization useful for research comparison.The need to avoid the development of post-hepatectomy liver failure represents the "conditio sine qua non" of surgical choice and the role of the current tools available for the assessment of liver function reserve were investigated.Results of hepatic resection in relationship with tumor burden were compared with those of available competing strategies,namely,radiofrequency ablation for early stages,and trans-arterial chemoembolization for intermediate and advanced stages.Finally,the choice for anatomical versus non-anatomical,as well as the role of laparoscopic approach,was overviewed.The literature review suggests that partial hepatectomy for HCC should be considered in the context of multi-disciplinary evaluation of cirrhotic patients.Scientific research on HCC has moved,in recent years,from surgical therapy toward non-surgical approaches and most of the literature regarding topics debated in the present review is represented by observational studies,whereas very few well-designed randomized controlled trials are currently available;thus,no robust recommendations can be derived.

Neoadjuvant chemoradiotherapy for resectable esophageal carcinoma:A meta-analysis

AIM:To compare neoadjuvant chemoradiotherapy and surgery with surgery alone for resectable esophageal carcinoma. METHODS:We used MEDLINE and EMBASE databases to identify eligible studies and manual searches were done to ensure no studies were missed.Trial validity assessment was performed and a trial quality score was assigned. RESULTS:Eleven randomized controlled trials(RCTs) including 1308 patients were selected.Neoadjuvant chemoradiotherapy significantly improved the overall survival compared with surgery alone.Odds ratio(OR) [95%confidence interval(CI),P value],expressed as neoadjuvant chemoradiotherapy and surgery vs surgery alone,was 1.28(1.01-1.64,P=0.05)for 1-year survival,1.78(1.20-2.66,P=0.004)for 3-year survival,and 1.46(1.07-1.99,P=0.02)for 5-year survival.Postoperative mortality increased in patients treated by neoadjuvant chemoradiotherapy(OR: 1.68,95%CI:1.03-2.73,P=0.04),but incidence of postoperative complications was similar in two groups (OR:1.14,95%CI:0.88-1.49,P=0.32).Neoadjuvant chemoradiotherapy lowered the local-regional cancer recurrence(OR:0.64,95%CI:0.41-0.99,P=0.04), but incidence of distant cancer recurrence was similar (OR:0.94,95%CI:0.68-1.31,P=0.73).Histological subgroup analysis indicated that esophageal squamous cell carcinoma did not benefit from neoadjuvantchemoradiotherapy,OR(95%CI,P value)was 1.16(0.85-1.57,P=0.34)for 1-year survival,1.34 (0.98-1.82,P=0.07)for 3-year survival and 1.41 (0.98-2.02,P=0.06)for 5-year survival. CONCLUSION:Neoadjuvant chemoradiotherapy can raise the survival rate of patients with esophageal adenocarcinoma.

Hemihepatic versus total hepatic inflow occlusion during hepatectomy:A systematic review and meta-analysis

AIM： To evaluate the clinical outcomes of patients undergoing hepatectomy with hemihepatic vascular occlusion （HHO） compared with total hepatic inflow occlusion （THO）. METHODS： Randomized controlled trials （RCTs） co- mparing hemihepatic vascular occlusion and total he- patic inflow occlusion were included by a systematic literature search. Two authors independently assessed the trials for inclusion and extracted the data. A meta- analysis was conducted to estimate blood loss, transfu- sion requirement, and liver injury based on the levels of aspartate aminotransferase （AST） and alanine arni- notransferase （ALT）. Either the fixed effects model or random effects model was used. RESULTS- Four RCTs including 338 patients met the predefined inclusion criteria. A total of 167 patients were treated with THO and 171 with HHO. Metaanalysis of AST levels on postoperative day 1 indicated higher levels in the THO group with weighted mean dif- ference （WMD） 342.27; 95% confidence intervals （CI） 217.28-467.26; P = 0.00001; I2 = 16%. Meta-analysis showed no significant difference between THO group and HHO group on blood loss, transfusion requirement, mortality, morbidity, operating time, ischemic duration, hospital stay, ALT levels on postoperative day 1, 3 and 7 and AST levels on postoperative day 3 and 7. CONCLUSION： Hemihepatic vascular occlusion does not offer satisfying benefit to the patients undergoing hepatic resection. However, they have less liver injury after liver resections.

Comparative study of laparoscopic vs open gastrectomy in gastric cancer management

AIM:To compare long-term results of gastric cancer patients undergoing laparoscopic and open gastrec-tomy in a single unit.METHODS:From February 2000 to September 2004,all patients with adenocarcinoma of the stomach were assessed to entry in this longitudinal prospective non-randomized trial.Primary endpoint was cancer-related survival and secondary endpoints were overall survival,evaluation of surgical complications and mortality.RESULTS:Fifty-eight patients were enrolled.Forty-seven patients were followed-up(range 11-103,me-dian 38 mo).Four patients were lost at follow up.Twenty-two patients underwent a laparoscopic gastric surgery(LGS)and 25 had a standard open procedure(OGS).No statistical difference was found between the two groups in terms of 5 years cancer-related mortality rate(50% vs 52%,P = 1),and 5 years overall mortal-ity rate(54.5% vs 56%,P = 1).Accordingly,cancer-related and overall survival probability by Kaplan-Meier method showed comparable results(P = 0.81 and P = 0.83,respectively).We found no differences in surgical complications in the 2 groups.There was no conversion to open surgery in this series.CONCLUSION:LGS is as effective as OGS in the man-agement of advanced gastric cancer.However LGS can-not be recommended routinely over OGS for the treat-ment of advanced gastric cancer.

Advances in diagnosis, treatment and palliation of pancreatic carcinoma: 1990-2010

Several advances in genetics, diagnosis and palliation of pancreatic cancer (PC) have occurred in the last decades. A multidisciplinary approach to this disease is therefore recommended. PC is relatively common as it is the fourth leading cause of cancer related mortality. Most patients present with obstructive jaundice, epigastric or back pain, weight loss and anorexia. Despite improvements in diagnostic modalities, the majority of cases are still detected in advanced stages. The only curative treatment for PC remains surgical resection. No more than 20% of patients are candidates for surgery at the time of diagnosis and survival remains quite poor as adjuvant therapies are not very effective. A small percentage of patients with borderline non-resectable PC might benefit from neo-adjuvant chemoradiation therapy enabling them to undergo resection; however, randomized controlled studies are needed to prove the benefits of this strategy. Patients with unresectable PC benefit from palliative interventions such as biliary decompression and celiac plexus block. Further clinical trials to evaluate new chemo and radiation protocols as well as identification of genetic markers for PC are needed to improve the overall survival of patients affected by PC, as the current overall 5-year survival rate of patients affected by PC is still less than 5%. The aim of this article is to review the most recent high quality literature on this topic.

Role of surgery in severe ulcerative colitis in the era of medical rescue therapy

Despite the growing use of medical salvage therapy,colectomy has remained a cornerstone in managing acute severe ulcerative colitis(ASC) both in children and in adults.Colectomy should be regarded as a life saving procedure in ASC,and must be seriously considered in any steroid-refractory patient.However,colectomy is not a cure for the disease but rather the substitution of a large problem with smaller problems,including fecal incontinence,pouchitis,irritable pouch syndrome,cuffitis,anastomotic ulcer and stenosis,missed or de-novo Crohn's disease and,in young females,reduced fecundity.This notion has led to the widespread practice of offering medical salvage therapy before colectomy in most patients without surgical abdomen or toxic megacolon.Medical salvage therapies which have proved effective in the clinical trial setting include cyclosporine,tacrolimus and infliximab,which seem equally effective in the short term.Validated predictive rules can identify a subset of patients who will eventually fail corticosteroid therapy after only 3-5 d of steroid therapy with an accuracy of 85%-95%.This accuracy is sufficiently high for initiat-ing medical therapy,but usually not colectomy,early in the admission without delaying colectomy if required.This approach has reduced the colectomy rate in ASC from 30%-70% in the past to 10%-20% nowadays,and the mortality rate from over 70% in the 1930s to about 1%.In general,restorative proctocolectomy(ileoanal pouch or ileal pouch-anal anastomosis),especially the J-pouch,is preferred over straight pullthrough(ileo-anal) or ileo-rectal anastomosis,which may still be considered in young females concerned about infertility.Colectomy in the acute severe colitis setting,is usually performed in three steps due to the severity of the inflammation,concurrent steroid treatment and the generally reduced clinical condition.The first surgical step involves colectomy and constructing an ileal stoma,the second-constructing the pouch and the third-closing the stoma.This review focuses on the role of surgical treatment in ulcerative colitis in the era of medical rescue therapy.

Does antecolic reconstruction for duodenojejunostomy improve delayed gastric emptying after pylorus-preserving pancreaticoduodenectomy? A systematic review and meta-analysis

AIM:To evaluate whether antecolic reconstruction for duodenojejunostomy (DJ) can decrease delayed gastric emptying (DGE) rate after pylorus-preserving pancreaticoduodenectomy (PPPD) through literature review and meta-analysis. METHODS:Articles published between January 1991 and April 2012 comparing antecolic and retrocolic reconstruction for DJ after PPPD were retrieved from the databases of MEDLINE (PubMed), EMBASE, OVID and Cochrane Library Central. The primary outcome of interest was DGE. Either fixed effects model or random effects model was used to assess the pooled effect based on the heterogeneity. RESULTS:Five articles were identified for inclusion:two randomized controlled trials and three non-randomized controlled trials. The meta-analysis revealed that antecolic reconstruction for DJ after PPPD was associated with a statistically significant decrease in the incidence of DGE [odds ratio (OR), 0.06; 95% CI, 0.02-0.17; P < 0.00 001] and intra-operative blood loss [mean difference (MD), -317.68; 95% CI, -416.67 to -218.70; P < 0.00 001]. There was no significant difference between the groups of antecolic and retrocolic reconstruction in operative time (MD, 25.23; 95% CI, -14.37 to 64.83; P = 0.21), postoperative mortality, overall morbidity (OR, 0.54; 95% CI, 0.20-1.46; P = 0.22) and length of postoperative hospital stay (MD, -9.08; 95% CI, -21.28 to 3.11; P = 0.14). CONCLUSION:Antecolic reconstruction for DJ can decrease the DGE rate after PPPD.

Laparoscopic rectal cancer surgery: Where do we stand?

Large comparative studies and multiple prospective randomized control trials (RCTs) have reported equivalence in short and long-term outcomes between the open and laparoscopic approaches for the surgical treatment of colon cancer which has heralded widespread acceptance for laparoscopic resection of colon cancer. In contrast, laparoscopic total mesorectal excision (TME) for the treatment of rectal cancer has been welcomed with significantly less enthusiasm. While it is likely that patients with rectal cancer will experience the same benefits of early recovery and decreased postoperative pain from the laparoscopic approach, whether the same oncologic clearance, specifically an adequate TME can be obtained is of concern. The aim of the current study is to review the current level of evidence in the literature on laparoscopic rectal cancer surgery with regard to short-term and long-term oncologic outcomes. The data from 8 RCTs, 3 metaanalyses, and 2 Cochrane Database of Systematic Reviews was reviewed. Current data suggests that laparoscopic rectal cancer resection may benefit patients with reduced blood loss, earlier return of bowel function, and shorter hospital length of stay. Concerns that laparoscopic rectal cancer surgery compromises short-term oncologic outcomes including number of lymph nodes retrieved and circumferential resection margin and jeopardizes long-term oncologic outcomes has not conclusively been refuted by the available literature. Laparoscopic rectal cancer resection is feasible but whether or not it compromises short-term or long-term results still needs to be further studied.

Role of radiation therapy in the management of stage Ⅲ non-small cell lung cancers: current status and controversies

The treatment of stage Ⅲ non-small cell lung cancer(NSCLC) consisting of the heterogeneous stage subsets remains a challenge. Overall, it has been gradually recognized that radiation therapy(RT) plays a crucial role in the management of stage Ⅲ NSCLC. One superior sulcus tumors are the subset for which the trimodality treatments are clearly preferred. One subset of stage Ⅲ NSCLC has a minimal disease burden with microscopic p N2 disease or with discrete p N2 involvement identified preoperatively, thus technically could undergo a surgical resection. For the incidentally found p N2 disease after complete surgery(ⅢA-1, ⅢA-2), the value of postoperative radiotherapy(PORT) has been recognized by a reassessment based on new data. However, doubt persists regarding how to define the clinical target volume for PORT. For the discrete p N2 involvement identified preoperatively(a selected part of ⅢA-3), induction chemoradiation therapy(CRT) before surgery may yield a survival advantage, although the phase Ⅲ randomized trials in this issue are not conclusive. The other major subset of stage Ⅲ NSCLC is the infiltrative stage Ⅲ NSCLC with N2 or N3 nodal disease(ⅢA-3, ⅢA-4, and ⅢB), for which concurrent CRT is considered as the current standard of care. The potential role of radiation dose escalation/acceleration has been proposed; however, the optimal dose fractionation remains an important unresolved question. Additionally, the role of prophylactic cranial irradiation for stage Ⅲ patients with high risk of brain metastasis is worth of further assessment. Moreover, how to integrate molecular targeted therapy with RT, as well as whether they had a role in stage Ⅲ diseases, are other controversies actively under study in ongoing trials. This review specifically describes the updated role of RT in multimodal approach to treat stage Ⅲ NSCLC and the controversies regarding these results in various situations.

Secondary hepatic resection as a therapeutic goal in advanced colorectal cancer

Surgery is the only curative option for patients with liver metastases of colorectal cancer, but few patients present with resectable hepatic lesions. Chemotherapy is increasingly used to downstage initially unresectable disease and allow for potentially curative surgery. Standard chemotherapy regimens convert 10%-20% of cases to resectable disease in unselected populations and 30%-40% of those with disease confined to the liver. One strategy to further increase the number of candidates eligible for surgery is the addition of active targeted agents such as cetuximab and bevacizumab to standard chemotherapy. Data from a phase Ⅲ trial indicate that cetuximab increases the number of patients eligible for secondary hepatic resection, as well as the rate of complete resection when combined with first-line treatment with the FOLFIRI regimen. The safety profiles of preoperative cetuximab or bevacizumab have not been thoroughly assessed, but preliminary evidence indicates that these agents do not increase surgical mortality or exacerbate chemotherapyrelated hepatotoxicity, such as steatosis （5-fluorouracil）, steatohepatitis （irinotecan）, and sinusoidal obstruction （oxaliplatin）. Secondary resection is a valid treatment goal for certain patients with initially unresectable liver metastases and an important end point for future clinical trials.

Vedolizumab use in patients with inflammatory bowel diseases undergoing surgery:clinical trials and post-marketing experience

Background:Patients with inflammatory bowel diseases frequently require surgery,but immunotherapies used in disease management may increase the risk of post-operative complications.We investigated frequencies of post-operative complications in patients who received vedolizumab—a gut-selective antibody approved for the treatment of moderately to severely active ulcerative colitis and Crohn’s disease—in clinical-trial and post-marketing settings.Methods:This post hoc analysis of safety data from GEMINI 1,GEMINI 2,and long-term safety studies included patients who had had colectomy or bowel surgery/resection.Data from the post-marketing Vedolizumab Global Safety Database were also analysed(data cutoff point:19 May 2016).Adverse events relating to post-operative complications were identified using Medical Dictionary for Regulatory Activities preferred terms.Results:Of 58 total surgeries in patients included in GEMINI 1 and GEMINI 2,post-operative complications were reported for 3/51 vedolizumab-treated patients(5.9%)and 1/7 placebo-treated patients(14.3%).In the long-term safety study,157/2,243 patients(7%)had colectomy or bowel surgery/resection;of these 157 patients who underwent surgery,11(7%)experienced a post-operative complication.Median time between last pre-operative vedolizumab dose and surgery was 23 days in GEMINI 1,20 days in GEMINI 2,and 39–40 days in the long-termsafety study.In the post-marketing setting,based on data covering approximately 46,978 patient-years of vedolizumab exposure,post-operative complications were reported in 19 patients.Conclusions:In clinical trials,complications of colectomy and bowel surgery/resection appeared infrequent,with minimal difference between vedolizumab and placebo.The frequency of post-operative complications in the post-marketing setting appears low.

Biomechanical experiment and clinical report of modified patellectomy for polar fracture of the patella

Objective: To study the influence of polar patel lectomy and the site of reanchored the patellar tendon on femoral quadriceps extensing force. Methods: The experiment was designed by using 5 lower limbs of cadavers for extracorporal biodynamic test. The maximal fixing force of the double stainless steel wire ( 0.4 mm in diameter) reanchoring the patellar ligament to the patellar cortical edge was measured. Clinically 21 patients with polar fractures were treated by removing the small fragments and reanchoring the patellar ligament to the cortical edge of the patella using the wires. Results: Resection of the lower 1/4 part of the patella and the patellar ligament reanchored to cortical edge of the patella would not increase femoral quadriceps contracting force arm. But if the patellar tendon reanchored near the joint surface, much more extending force would be needed than the former (P<0.001). The maximal fixing force of the wires is 67.4 kg (60.9 72.5 kg). All the patients using this modified procedure gained satisfactory functional recovery. Conclusions: The modified partial patellecomy is a simple and effective procedure for choice.