AIM:To evaluate the safety and effectiveness of twostage vs single-stage management for concomitant gallstones and common bile duct stones.METHODS:Four databases,including PubMed,Embase,the Cochrane Central Register o...AIM:To evaluate the safety and effectiveness of twostage vs single-stage management for concomitant gallstones and common bile duct stones.METHODS:Four databases,including PubMed,Embase,the Cochrane Central Register of Controlled Trials and the Science Citation Index up to September 2011,were searched to identify all randomized controlled trials(RCTs).Data were extracted from the studies by two independent reviewers.The primary outcomes were stone clearance from the common bile duct,postoperative morbidity and mortality.The secondary outcomes were conversion to other procedures,number of procedures per patient,length of hospital stay,total operative time,hospitalization charges,patient acceptance and quality of life scores.RESULTS:Seven eligible RCTs [five trials(n = 621) comparing preoperative endoscopic retrograde cholangiopancreatography(ERCP)/endoscopic sphincterotomy(EST) + laparoscopic cholecystectomy(LC) with LC + laparoscopic common bile duct exploration(LCBDE);two trials(n = 166) comparing postoperative ERCP/EST + LC with LC + LCBDE],composed of 787 patients in total,were included in the final analysis.The metaanalysis detected no statistically significant difference between the two groups in stone clearance from the common bile duct [risk ratios(RR) =-0.10,95% confidence intervals(CI):-0.24 to 0.04,P = 0.17],postoperative morbidity(RR = 0.79,95% CI:0.58 to 1.10,P = 0.16),mortality(RR = 2.19,95% CI:0.33 to 14.67,P = 0.42),conversion to other procedures(RR = 1.21,95% CI:0.54 to 2.70,P = 0.39),length of hospital stay(MD = 0.99,95% CI:-1.59 to 3.57,P = 0.45),total operative time(MD = 12.14,95% CI:-1.83 to 26.10,P = 0.09).Two-stage(LC + ERCP/EST) management clearly required more procedures per patient than single-stage(LC + LCBDE) management.CONCLUSION:Single-stage management is equivalent to two-stage management but requires fewer procedures.However,patient's condition,operator's expertise and local resources should be taken into account in making treatment decisions.展开更多
AIM:To quantitatively assess the relationship between coffee consumption and incidence of pancreatic cancer in a meta-analysis of cohort studies. METHODS:We searched MEDLINE,EMBASE,Science Citation Index Expanded and ...AIM:To quantitatively assess the relationship between coffee consumption and incidence of pancreatic cancer in a meta-analysis of cohort studies. METHODS:We searched MEDLINE,EMBASE,Science Citation Index Expanded and bibliographies of retrieved articles.Studies were included if they reported relative risks(RRs)and corresponding 95%CIs of pancreatic cancer with respect to frequency of coffee intake.We performed random-effects meta-analyses and metaregressions of study-specific incremental estimates to determine the risk of pancreatic cancer associated with a 1 cup/d increment in coffee consumption. RESULTS:Fourteen studies met the inclusion criteria, which included 671 080 individuals(1496 cancer events) with an average follow-up of 14.9 years.Compared with individuals who did not drink or seldom drank coffee per day,the pooled RR of pancreatic cancer was 0.82 (95%CI:0.69-0.95)for regular coffee drinkers,0.86 (0.76-0.96)for low to moderate coffee drinkers,and 0.68(0.51-0.84)for high drinkers.In subgroup analyses,we noted that,coffee drinking was associated witha reduced risk of pancreatic cancer in men,while this association was not seen in women.These associations were also similar in studies from North America,Europe, and the Asia-Pacific region. CONCLUSION:Findings from this meta-analysis suggest that there is an inverse relationship between coffee drinking and risk of pancreatic cancer.展开更多
We consider the random difference equations S =_d(X + S)Y and T =_dX + TY, where =_ddenotes equality in distribution, X and Y are two nonnegative random variables, and S and T on the right hand side are independent of...We consider the random difference equations S =_d(X + S)Y and T =_dX + TY, where =_ddenotes equality in distribution, X and Y are two nonnegative random variables, and S and T on the right hand side are independent of(X, Y). Under the assumptions that X follows a subexponential distribution with a nonzero lower Karamata index, that Y takes values in [0, 1] and is not degenerate at 0 or 1, and that(X, Y) fulfills a certain dependence structure via the conditional tail probability of X given Y, we derive some asymptotic formulas for the tail probabilities of the weak solutions S and T to these equations. In doing so we also obtain some by products which are interesting in their own right.展开更多
文摘AIM:To evaluate the safety and effectiveness of twostage vs single-stage management for concomitant gallstones and common bile duct stones.METHODS:Four databases,including PubMed,Embase,the Cochrane Central Register of Controlled Trials and the Science Citation Index up to September 2011,were searched to identify all randomized controlled trials(RCTs).Data were extracted from the studies by two independent reviewers.The primary outcomes were stone clearance from the common bile duct,postoperative morbidity and mortality.The secondary outcomes were conversion to other procedures,number of procedures per patient,length of hospital stay,total operative time,hospitalization charges,patient acceptance and quality of life scores.RESULTS:Seven eligible RCTs [five trials(n = 621) comparing preoperative endoscopic retrograde cholangiopancreatography(ERCP)/endoscopic sphincterotomy(EST) + laparoscopic cholecystectomy(LC) with LC + laparoscopic common bile duct exploration(LCBDE);two trials(n = 166) comparing postoperative ERCP/EST + LC with LC + LCBDE],composed of 787 patients in total,were included in the final analysis.The metaanalysis detected no statistically significant difference between the two groups in stone clearance from the common bile duct [risk ratios(RR) =-0.10,95% confidence intervals(CI):-0.24 to 0.04,P = 0.17],postoperative morbidity(RR = 0.79,95% CI:0.58 to 1.10,P = 0.16),mortality(RR = 2.19,95% CI:0.33 to 14.67,P = 0.42),conversion to other procedures(RR = 1.21,95% CI:0.54 to 2.70,P = 0.39),length of hospital stay(MD = 0.99,95% CI:-1.59 to 3.57,P = 0.45),total operative time(MD = 12.14,95% CI:-1.83 to 26.10,P = 0.09).Two-stage(LC + ERCP/EST) management clearly required more procedures per patient than single-stage(LC + LCBDE) management.CONCLUSION:Single-stage management is equivalent to two-stage management but requires fewer procedures.However,patient's condition,operator's expertise and local resources should be taken into account in making treatment decisions.
文摘AIM:To quantitatively assess the relationship between coffee consumption and incidence of pancreatic cancer in a meta-analysis of cohort studies. METHODS:We searched MEDLINE,EMBASE,Science Citation Index Expanded and bibliographies of retrieved articles.Studies were included if they reported relative risks(RRs)and corresponding 95%CIs of pancreatic cancer with respect to frequency of coffee intake.We performed random-effects meta-analyses and metaregressions of study-specific incremental estimates to determine the risk of pancreatic cancer associated with a 1 cup/d increment in coffee consumption. RESULTS:Fourteen studies met the inclusion criteria, which included 671 080 individuals(1496 cancer events) with an average follow-up of 14.9 years.Compared with individuals who did not drink or seldom drank coffee per day,the pooled RR of pancreatic cancer was 0.82 (95%CI:0.69-0.95)for regular coffee drinkers,0.86 (0.76-0.96)for low to moderate coffee drinkers,and 0.68(0.51-0.84)for high drinkers.In subgroup analyses,we noted that,coffee drinking was associated witha reduced risk of pancreatic cancer in men,while this association was not seen in women.These associations were also similar in studies from North America,Europe, and the Asia-Pacific region. CONCLUSION:Findings from this meta-analysis suggest that there is an inverse relationship between coffee drinking and risk of pancreatic cancer.
基金supported by the National Science Foundation of the United States (Grant No. CMMI-1435864)
文摘We consider the random difference equations S =_d(X + S)Y and T =_dX + TY, where =_ddenotes equality in distribution, X and Y are two nonnegative random variables, and S and T on the right hand side are independent of(X, Y). Under the assumptions that X follows a subexponential distribution with a nonzero lower Karamata index, that Y takes values in [0, 1] and is not degenerate at 0 or 1, and that(X, Y) fulfills a certain dependence structure via the conditional tail probability of X given Y, we derive some asymptotic formulas for the tail probabilities of the weak solutions S and T to these equations. In doing so we also obtain some by products which are interesting in their own right.
