重度子痫前期产妇剖宫产布比卡因蛛网膜下腔阻滞麻醉适合剂量的临床研究

目的 探讨重度子痫前期产妇剖宫产重比重布比卡因蛛网膜下腔阻滞麻醉（腰麻）的适合剂量。方法 选取200例重度子痫前期产妇,ASAⅠ级或Ⅱ级,按随机数字表法分为4组,每组各50 例,相应各组鞘内注入布比卡因剂量分别为10、8、6 及4mg,并混合2.5μg 舒芬太尼。选择L3~4行腰硬联合穿刺,注药10min 后记录麻醉平面。根据结果进行Probit 回归分析,计算布比卡因腰麻的ED50和ED95。观察各组利多卡因及去氧肾上腺素的用量、肌松效果及患者麻醉满意度,观察各组术中并发症以及新生儿的Apgar 评分和脐动脉pH。结果 重度子痫前期患者腰麻剖宫产布比卡因ED50 和ED95分别为：6.51（95%CI：5.81～7.01）和8.68（95%CI：7.96～10.26）。4 组患者10min 后麻醉平面的差异均有统计学意义（均P＜0.05）。4mg 组利多卡因用量高于其他3组,差异有统计学意义（P＜0.05）。8mg 组、10mg 组去氧肾上腺素的用量高于其他两组,差异均有统计学意义（均P＜0.05）。低血压的发生率8mg 组、10mg 组高于其他两组,差异均有统计学意义（均P＜0.05）。４ 组间其他不良反应恶心、呕吐、寒战以及心动过缓发生率的差异无统计学意义（P＞0.05）。4 组胎儿娩出后1、5min Apgar 评分及脐动脉血气分析的结果差异均无统计学意义（均P＞0.05）。结论 重度子痫前期产妇剖宫产鞘内注入6mg 布比卡因混合2.5μg舒芬太尼,必要时辅以硬膜外麻醉,麻醉效果确切,血流动力学稳定,适合该类患者手术麻醉。     

罗哌卡因用于剖宫产术蛛网膜下腔阻滞注药速度的研究

目的 探讨罗哌卡因用于剖宫产术蛛网膜下腔阻滞的合理注药速度。方法 选择行剖宫产术产妇90 例,按蛛网膜 下腔阻滞时罗哌卡因注药时间采用随机数字表法分为30s 组、60s 组、90s 组,每组各30例。观察并记录麻醉前（T0）、麻醉后1min（T1）、5min（T2）、10min（T3）、20min（T4）收缩压（SBP）、舒张压（DBP）、心率（HR）变化,术中恶心、呕吐、胸闷、麻黄碱、阿托品使用例数,麻醉最高平面情况。结果 与60s 组、90s 组相比,30s 组SBP、DBP、HR 下降更为显著,发生恶心、呕吐、胸闷等不良反应及使用麻黄碱例数显著增多（P＜0.05）。30s 组、60s 组、90s 组产妇麻醉平面达T6以上分别为29 例、29 例、28例,均能满足手术要求,最高阻 滞平面达T4、T2的例数30s 组显著多于60s 组、90s 组（P＜0.05）。结论 常规剂量罗哌卡因用于蛛网膜下腔阻滞下剖宫产术,其注药时间宜控制在60～90s,同样能满足手术需要,且可减少不良反应的发生,而不是传统方法的15～30s。     

罗哌卡因复合芬太尼硬膜外用药对分娩方式的影响

目的探讨硬膜外罗哌卡因复合芬太尼分娩镇痛对分娩方式的影响。方法回顾7136例具备顺产条件初产妇的最终分娩方式,按产妇意愿分为对照组（A组）4168例及分娩镇痛组（B组）2968例。A组产妇未接受分娩镇痛,B组产妇给予L2~3或L3~4硬膜外阻滞,头向置管后1%利多卡因5ml试验量确定阻滞平面后,予以6~15ml/h持续泵注0.15%罗哌卡因和2μg/ml芬太尼的复合液。记录汇总最终分娩方式及剖宫产原因,评定两组新生儿出生后1、5minApgar评分,评定产妇镇痛后的视觉模拟评分（VAS）及改良Bromage评分。结果B组产妇剖宫产率（20.28%）及产钳使用率（4.38%）明显高于A组（7.70%、2.33%,P＜0.01）;B组第一产程时间延长于A组(P＜0.01）;B组因第一产程延长而行剖宫产比例（64.62%）明显高于A组（42.81%,P＜0.01）;B组胎儿宫内窘迫的比例（12.29%）明显低于A组（31.25%,P＜0.01）;胎头下降停滞及羊水问题、胎位异常比例与A组比较差异均无统计学意义（均P＞0.05）。两组新生儿出生后1、5min的Apgar评分差异无统计学意义（P＞0.05）。B组产妇宫口6、10cm时的VAS评分明显低于A组（P＜0.01）,但两组产妇下肢改良Bromage评分差异无统计学意义（P＞0.05）。结论0.15%罗哌卡因复合2μg/ml芬太尼的硬膜外分娩镇痛可增加产妇剖宫产率、阴道器械助产率及延长第一产程,但对新生儿Apgar评分及产妇下肢肌力无影响。     

术中不同浓度氧对病态肥胖阻塞性睡眠呼吸暂停综合征患者术后早期动脉血氧分压的影响

目的观察术中吸入不同浓度氧对病态肥胖患者术后早期动脉血氧分压的影响。方法选择40例ASAⅢ级、因阻塞性睡眠呼吸暂停综合征（OSAS）拟择期行悬雍垂腭咽成形术的病态肥胖（BMI≥40kg／m^2）患者,采用随机数字表法分成80％氧浓度吸入组（H组）和60％氧浓度吸入组（L组）,各20例,测定术前（T0）、气管拔管后10min（T1）、0．5h（T2）、2h（T3）的动脉血气分析指标并作比较。结果两组患者1Io时动脉血气分析中的SaO2、PaO2、PaCO2、pH值的差异均无统计学意义（均P〉0．05）,在T1、T2、T3各时点L组的SaO2、PaO2值明显高于H组（P〈0．05或0．01）,在T、时点,L组的PaCO2明显低于H组（P〈0．05）。结论相较于80％的吸入氧浓度,病态肥胖的OSAS患者术中吸入60％浓度的氧,术后的氧合更好,有利于术后早期呼吸功能的恢复。     

碘伏术前消毒阴道、术中冲洗宫腔预防急诊剖宫产术后切口感染疗效观察

目的 探讨碘伏术前消毒阴道、术中冲洗宫腔对产妇急诊剖宫产术后腹部切口及子宫感染有无预防作用。方法 选取2010 年3 月至2014 年6 月行急诊剖宫产术的产妇218例,随机分为3组,均采用抗生素围术期用药（头孢唑啉钠针2.0g,术中断脐后及术后各1次,静脉滴注）。Ⅰ组（81 例）0.5%碘伏术前消毒阴道、术中冲洗宫腔;Ⅱ组（73 例）0.9%氯化钠溶液术中冲洗宫腔;Ⅲ组（64 例）不做上述处理,比较3 组产妇术后腹部切口及子宫感染发生率。结果 术后腹部切口感染：Ⅰ组3例,Ⅱ组2例,Ⅲ组4例;3组比较,差异无统计学意义（P＞0.05）;术后子宫感染：Ⅰ组2 例,Ⅱ组4 例,Ⅲ组7 例;Ⅰ组与Ⅲ组比较,差异有统计学意义（P＜0.05）;Ⅰ组与Ⅱ组、Ⅱ组与Ⅲ组比较,差异均无统计学意义（均P＞0.05）。结论 在合理预防性使用抗生素前提下,碘伏术前消毒阴道、术中冲洗宫腔可降低急诊剖宫产术后子宫感染发生率。     

无创正压通气治疗COPD 合并肺源性心脏病的疗效及对血浆C反应蛋白和脑钠素水平的影响

目的 探讨无创正压通气对慢性阻塞性肺疾病（COPD）合并肺源性心脏病的疗效和对患者血浆C 反应蛋白（CRP）和脑钠素（BNP）水平的影响。方法 将2012 年1 月到2014 年1月收治的120 例COPD 急性加重期合并肺源性心脏病患者随机分为观察组（60 例）和对照组（60 例）,对照组给予常规治疗,观察组在此基础上给予无创正压通气治疗。治疗前和治疗3d 后分别进行动脉血气分析,比较患者血pH 值、PaO2、PaCO2和动脉血氧饱和度（SaO2）在治疗前后的改变,并监测治疗前后血浆CRP和BNP 水平的改变。结果 治疗3d 后,两组患者的pH 值、PaO2、SaO2均较治疗前明显升高,PaCO2较治疗前明显降低,而观察组患者治疗后的动态血气分析指标的改善情况明显优于对照组,均有统计学差异（均P＜0.05）。两组患者的血浆CRP 和BNP 水平均较治疗前明显降低,而观察组患者治疗后的血浆CRP 和BNP 水平明显低于对照组,均有统计学差异（均P＜0.05）。结论 无创正压通气治疗COPD 合并肺源性心脏病,能够有效改善血气指标,提高SaO2和PaO2,同时降低血浆CRP 和BNP 的水平,值得在临床推广应用。     

缩宫素宫颈注射联合卡前列甲酯栓在阴道分娩产后出血中的运用

目的探讨缩宫素宫颈注射联合卡前列甲酯栓在阴道分娩产后出血中的运用。方法选取阴道分娩产后出血的121例产妇随机分成3组：I组（41例）予以缩宫素10U宫颈注射并给予卡前列甲酯栓1枚（1mg）直肠用药；II组（40例）予以缩宫素10U宫颈注射；III组（40例）给予卡前列甲酯栓1枚（1mg）直肠用药；3组同时辅以子宫按摩，促进子宫复旧。观察用药后阴道出血减少时间、出血量以及不良反应情况。结果 I、II组与III组比较，阴道出血减少时间均有统计学差异（均P＜0.05）；I、II组之间比较，无统计学差异（P＞0.05）。I组与II、III组相比较，用药后阴道出血量均有统计学差异（均P＜0.05）,而II、III两组比较无统计学差异（P＞0.05）；用药后不良反应，3组间无统计学差异（P＞0.05）。结论缩宫素宫颈注射联合卡前列甲酯栓用于防治阴道分娩产后出血，不良反应少，使用快捷简便、安全有效、持久。     

急性等容血液稀释对外伤性颅内血肿患者的脑保护作用

目的探讨急性等容血液稀释（ANH）对外伤性颅内血肿患者的脑保护作用。方法56例外伤性颅内血肿患者按随机数字表法分为血液稀释组（H组）28例和对照组（C组）28例。H组于术前行ANH,目标红细胞压积（Hct）为30％。两组患者分别于术前（T0）、手术开始后2h（T1）抽取静脉血测定血液流变学指标、脑组织氧代谢指标、S-100B蛋白浓度。结果两组患者T0时的全血黏度高切、全血黏度中切、全血黏度低切、血浆黏度、红细胞聚集指数、红细胞刚性指数的差异均无统计学意义（均P＞0.05）。T1时, H组上述各指标均明显低于C组,两组间的差异均有统计学意义（均P＜0.05）。T0时,两组患者乳酸（VLAC）、颈内静脉球血氧饱和度（SjvO2）、动脉-颈内静脉球部血氧含量差（Da-jvO2）的差异均无统计学意义（均P＞0.05）;T1时,两组患者的SjvO2均有所降低,且H组高于C组,两组间的差异有统计学意义（P＜0.05）;而VLAC、Da-jvO2较T0时均升高,且H组低于C组,两组间的差异有统计学意义（P＜0.05）。T0时,两组患者的血清S-100B蛋白浓度的差异无统计学意义（P＞0.05）;T1时,两组患者的差异有统计学意义（P＜0.05）。结论 ANH可以降低血液黏度,减少血清中S-100B蛋白浓度,改善脑外伤后脑组织氧代谢紊乱,具有一定的脑保护作用。     

连续臂丛神经阻滞镇痛对断指再植血流动力学影响的研究

目的研究连续臂丛神经阻滞镇痛对断指再植术后再植指血流动力学的影响，探讨其缓解血管痉挛、增加血流量的可行性。方法将60例急诊行断指再植术患者按随机数字表法分为术后连续臂丛神经阻滞镇痛组（CA组）和对照组（NA组），每组30例。观察两组患者再植指术后血管痉挛、血管栓塞和指体坏死发生例数并计算再植指成活率，记录两组术后即刻（T1）、术后24h（T2）再植指固有动脉血流动力学参数及动脉内径（AD）、远指端血氧饱和度（SpO2）和温度（Ts）变化。结果断指再植术后成活率CA组高于NA组，血管痉挛、血管栓塞和指体坏死发生率CA组均低于NA组，差异均有统计学意义（均P＜0.05）。在T2时CA组各项血流动力学参数、AD、SpO2、Ts均高于NA组，阻力指数（RI）低于NA组，差异均有统计学意义（均P＜0.05）。结论术后连续臂丛神经阻滞镇痛可以缓解再植指固有动脉痉挛，增加指体血流量，提高了断指再植的成功率。     

下肢静脉曲张腔内激光治疗与传统剥脱手术治疗的远期疗效对比研究

目的 比较静脉腔内激光治疗（EVLT）和传统剥脱手术治疗下肢静脉曲张（VVLE）的远期疗效。方法 选取VVLE患者120例,随机分为EVLT 组与对照组,每组各60例。EVLT组采用EVLT治疗,对照组采用传统剥脱手术治疗。分别对两组患者手术并发症、术后1、2、3 年复发率以及术后生活质量进行对比评价。结果 术后3 个月EVLT 组患者生活质量调查表（CIVIQ）评分显著高于对照组（P＜0.05）,术后6 个月两组患者CIVIQ 评分比较则无统计学差异（P＞0.05）。EVLT 组患者术后皮下瘀血、感觉麻木、硬结、皮下脂肪液化感染的发生率均显著低于对照组（均P＜0.01）,皮肤灼伤的发生率则高于对照组（P＜0.05）,两组患者静脉炎的发生率无统计学差异（P＞0.05）;两组患者术后1、2、3年复发率比较均无统计学差异（均P＞0.05）。结论 应用EVLT治疗VVLE 手术并发症少,患者术后恢复较快,远期疗效理想,值得临床推广应用。     

Filling in solvable groups and in lattices in semisimple groups

We prove that the filling order is quadratic for a large class of solvable groups and asymptotically quadratic for all -rank one lattices in semisimple groups of -rank at least 3. As a byproduct of auxiliary results we give a shorter proof of the theorem on the nondistorsion of horospheres providing also an estimate of a nondistorsion constant.     

Introducing technology in algebra in Hong Kong: addressing issues in learning

A review of recent studies in Hong Kong suggests that possible problems in secondary school algebra may be due to the procedural paradigm orientation in the curriculum and the conventional style of teaching in the classroom which do not provide sufficient opportunities for students to develop conceptual understanding. Based on the works of a number of projects in the West, it is hypothesized that the introduction of technology in lessons which embody a cognitive model in their design and delivery will provide a viable alternative for enhancing algebraic thinking. The key features of the cognitive model are concrete preparation, cognitive conflict, construction, metacognition and bridging, imbedded in a ‘mediation’ style of teaching. These features are exemplified by detailed accounts of classroom episodes from a Hong Kong lesson supported by the use of graphics calculators. Results indicate that while the approach places particular demands on teachers (a tension between a transmission style of teaching and mediating) there is real potential for supporting more dynamic student constructions.     

抓好数学建模竞赛 推动数学教学改革

本文通过近几年组织数学建模教学和指导学生参加竞赛的实践 ,探索抓好数学建模竞赛 ,促进数学教学改革 ,推动数学素质教育 ,提高人才培养质量的途径、措施和方法     

Nonlinear problems arising in electrostatic actuation in MEMS

In this paper we study the nonlinear problem arising in electrostatic actuation of MEMS. We show that the existence and non-existence of the solution of this problem depend on the value of the physical parameters of the equation. In addition we consider the corresponding initial value problem and we derived the existence of periodic solution, stability of steady states and the ω-limit set.     

Equality in Distribution in a Convex Ordering Family

Let F and G be the respective distributions of nonnegative random variables X and Y satisfying the convex ordering. We investigate the class of functions h for which the equality E[h(X)] = E[h(Y)] guarantees F = G. It leads to extensions of some existing results and at the same time offers a somewhat simpler proof.     

An Outlook in Teaching and Research in Mathematics in Educational Institutions

The present paper outlines some basic principles upon which an outlook in teaching and research in mathematics in educational institutions can be developed. Defining applied mathematics, the author analyses the basic topics of mathematics which permeate throughout the wider fields and diversified aspects of this branch of mathematical science.

For the institutions of learning, a course curriculum has been proposed which will gradually motivate, orient and prepare individuals through the process of learning to understand the methods and techniques, so as to apply them to physical problems. This has been illustrated in the fields of fluid dynamics and aerodynamics through the analysis of complex function theory and differential equations.

Because of the frustrating situations prevailing amongst students and teachers in the institutions of learning in the present day, a critical analysis has been made to identify the respective roles of the academicians and administrators, and with a view to improving the situation, some remedy has been suggested regarding teaching and research in educational institutions.     

Incentive regulation and the change in productive efficiency in telecommunications in the United States

Incentive regulation has become an important regulatory tool in the telecommunications industry in the United States. The issue explored here is whether incentive regulation has resulted in an increase in productive efficiency. After providing an overview of the nature of incentive regulation, a methodology for measuring technical inefficiency and its change is introduced. This is a stochastic frontier production function approach reflecting technical inefficiency effects. The results of implementing this methodology suggest that in the production of interLATA billed access minutes for interstate calls, there was no change in technical efficiency, something that incentive regulation was specifically designed to enhance. Finally, an assessment of technical efficiency across individual LECs in the United States indicates considerable variability. Published in 2001 by John Wiley & Sons, Ltd.     

Domination in a digraph and in its reverse

Let D be a digraph. By γ(D) we denote the domintaion number of D and by D⁻ we denote a digraph obtained by reversing all the arcs of D. In this paper we prove that for every δ≥3 and k≥1 there exists a simple strongly connected δ-regular digraph D_δ,k such that . Analogous theorem is obtained for total domination number provided that δ≥4.