目的：分析再手术治疗腰椎失败综合征（failed back surgery syndrome, FBSS）与初次腰椎手术的临床疗效,探讨提高手术临床疗效的方法和技巧。方法回顾分析2008年1月-2012年12月收治的再手术治疗腰椎失败综合征患者与初次腰椎手术患者...目的：分析再手术治疗腰椎失败综合征（failed back surgery syndrome, FBSS）与初次腰椎手术的临床疗效,探讨提高手术临床疗效的方法和技巧。方法回顾分析2008年1月-2012年12月收治的再手术治疗腰椎失败综合征患者与初次腰椎手术患者各30例患者的资料（随机抽取）,通过统计分析两组患者年龄、性别、手术时间及术式,比较两组患者临床疗效。结果全部患者随访6-24个月,平均随访14个月。再手术治疗腰椎失败综合征优10例,良15例,可4例,差1例,优良率83.3%；初次腰椎手术优17例,良10例,可3例,差0例,优良率90%。结论通过术前准确的诊断,严格把握手术适应证,制定合理的手术方案,再次手术治疗腰椎失败综合征可获得与初次腰椎手术同样令人满意的疗效。展开更多
Emergency physicians are often the first providersto encounter patients with complications in earlypregnancy. Point-of-care （POC） pelvic ultrasound isbeing increasingly used in the evaluation of emergencydepartment ...Emergency physicians are often the first providersto encounter patients with complications in earlypregnancy. Point-of-care （POC） pelvic ultrasound isbeing increasingly used in the evaluation of emergencydepartment （ED） patients with first trimester symptoms.[1]While the initial aim of POC ultrasound in this settingis to confirm an intrauterine pregnancy, a secondarygoal is to differentiate between a normal and abnormalpregnancy. There exist a number of sonographic featuresto suggest a pregnancy is non-viable.展开更多
Solving a quantified constraint satisfaction problem(QCSP)is usually a hard task due to its computational complexity.Exact algorithms play an important role in solving this problem,among which backtrack algorithms are...Solving a quantified constraint satisfaction problem(QCSP)is usually a hard task due to its computational complexity.Exact algorithms play an important role in solving this problem,among which backtrack algorithms are effective.In a backtrack algorithm,an important step is assigning a variable by a chosen value when exploiting a branch,and thus a good value selection rule may speed up greatly.In this paper,we propose two value selection rules for existentially and universally quantified variables,respectively,to avoid unnecessary searching.The rule for universally quantified variables is prior to trying failure values in previous branches,and the rule for existentially quantified variables selects the promising values first.Two rules are integrated into the state-of-the-art QCSP solver,i.e.,QCSP-Solve,which is an exact solver based on backtracking.We perform a number of experiments to evaluate improvements brought by our rules.From computational results,we can conclude that the new value selection rules speed up the solver by 5 times on average and 30 times at most.We also show both rules perform well particularly on instances with existentially and universally quantified variables occurring alternatively.展开更多
文摘目的：分析再手术治疗腰椎失败综合征（failed back surgery syndrome, FBSS）与初次腰椎手术的临床疗效,探讨提高手术临床疗效的方法和技巧。方法回顾分析2008年1月-2012年12月收治的再手术治疗腰椎失败综合征患者与初次腰椎手术患者各30例患者的资料（随机抽取）,通过统计分析两组患者年龄、性别、手术时间及术式,比较两组患者临床疗效。结果全部患者随访6-24个月,平均随访14个月。再手术治疗腰椎失败综合征优10例,良15例,可4例,差1例,优良率83.3%；初次腰椎手术优17例,良10例,可3例,差0例,优良率90%。结论通过术前准确的诊断,严格把握手术适应证,制定合理的手术方案,再次手术治疗腰椎失败综合征可获得与初次腰椎手术同样令人满意的疗效。
文摘Emergency physicians are often the first providersto encounter patients with complications in earlypregnancy. Point-of-care （POC） pelvic ultrasound isbeing increasingly used in the evaluation of emergencydepartment （ED） patients with first trimester symptoms.[1]While the initial aim of POC ultrasound in this settingis to confirm an intrauterine pregnancy, a secondarygoal is to differentiate between a normal and abnormalpregnancy. There exist a number of sonographic featuresto suggest a pregnancy is non-viable.
基金We would like to thank Dr.Peter Nightingale for the source code of QCSP-Solve.The work described in this paper was supported by the National Natural Science Foundation of China(Granted Nos.61972063,61763003,61672122,61602077,61402070)the Fundamental Research Funds for the Central Universities(3132019029,3132019355).
文摘Solving a quantified constraint satisfaction problem(QCSP)is usually a hard task due to its computational complexity.Exact algorithms play an important role in solving this problem,among which backtrack algorithms are effective.In a backtrack algorithm,an important step is assigning a variable by a chosen value when exploiting a branch,and thus a good value selection rule may speed up greatly.In this paper,we propose two value selection rules for existentially and universally quantified variables,respectively,to avoid unnecessary searching.The rule for universally quantified variables is prior to trying failure values in previous branches,and the rule for existentially quantified variables selects the promising values first.Two rules are integrated into the state-of-the-art QCSP solver,i.e.,QCSP-Solve,which is an exact solver based on backtracking.We perform a number of experiments to evaluate improvements brought by our rules.From computational results,we can conclude that the new value selection rules speed up the solver by 5 times on average and 30 times at most.We also show both rules perform well particularly on instances with existentially and universally quantified variables occurring alternatively.
