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31.
Recently many mammaplasty techniques have been presented with special attention paid to the resulting scar's size and its position. The surgeon should try to hid the scar, and if the inverted T incision is used, its horizontal branch should be as short as possible and kept in the breast area. Neverthelss, excessive concern about the final scar size should not interfere with the final results of the mammaplasty as far as shape, volume and lasting results are concerned. The author presents his experience in mammaplasty with respect to the volume, the shape, and the scar size interrelationships.  相似文献   
32.
Multiple pregnancies resulting from ovarian stimulation areat a higher risk of carrying at least one fetus affected byMendelian or chromosomal anomalies, the incidence of which isdirectly related to the order of multiples. Genetic analysisbefore fetal reduction was offered to both high-and low-riskpregnant women carrying two or more fetuses after ovulationinduction. Chorionic villus sampling (CVS) and fetal reductionwere achieved by transabdominal needling. The use of short-termculture, the polymerase chain reaction and fresh tissue enzymaticanalyses have made it possible for genetic diagnosis to be availablein a few days. A total of 100 patients had multifetal pregnancyreduction performed by a single operator; all of them completedpregnancy and none was lost at follow-up. The total fetal lossbefore 24 weeks was 7% and no statistically significant relationshipwas found with the final number of fetuses and CVS. Perinatallosses (3.9%) were only present in the series with a final numberof two fetuses. Pregnancy duration and birthweight were significantlyhigher in singletons than in twins, but were not related toCVS. The rate of chromosomal disorders was higher (7.2%) inthe study series than in singleton pregnancies not undergoingfetal reduction. Diagnostic error due to incorrect samplingwas reported in 1.5% of cases. These data support fetal reductionas a valuable strategy to improve the outcome of multiple pregnancy.The outcome of pregnancies reduced to singletons was significantlybetter than of those reduced to twins, and was not related toCVS. Therefore, prenatal genetic diagnosis should become anintegral part of counselling on multiple pregnancy, and is stronglyrecommended when reduction to singleton pregnancy is requested.  相似文献   
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The influence of the thickness of a carbon-supported platinum catalyst layer on the oxygen reduction reaction (orr) has been studied in sulfuric acid solution by means of a thin-film rotating disk electrode. Pronounced changes in the Pt utilization, electrode activity and the orr kinetics have been observed upon varying the catalyst layer thickness. The thicker film electrode exhibits a higher Pt utilization efficiency and higher activity, and promotes the orr kinetics at potentials relevant to fuel cell operations. The participation of Pt surfaces not in contact with the electrolyte solution in electrochemical reactions via the spillover of adsorbed hydrogen and oxygen species, is proposed to be responsible for the changes. The thicker catalyst layer is likely to modify the Pt particle–particle distance by providing shared Pt sites between adjacent carbon supports, to improve the surface density of active catalyst particles per single carbon support by sharing adjacent catalyst sites, and to increase the ratio of the particle surfaces free of blocking anions to the catalyst|electrolyte interface surfaces. The carbon-supported platinum catalyst layer becomes active at 0.90 V vs RHE only when the catalyst layer is thicker than 1 μm. To provide reasonable activity, the minimum catalyst layer thickness should be around 2–4 μm. These results should be considered in the design of the cathode catalyst layer of polymer electrolyte membrane fuel cells.  相似文献   
35.
目的 评价开放复位可塑形钛板内固定治疗跟骨骨折的疗效。方法 对33例(37足)以后关节突移位为主的跟骨骨折,行跟骨外侧入路、开放性复位可塑形钛板螺钉内固定,必要时行植骨术(18例)。结果 平均随访11.5个月,参照Mary—land food score评分,对患足是否疼痛、步态、距下关节及踝关节活动度、是否支架辅助、术后X线摄片等加以评估,19足疗效为优,17足为良,1足可。其中钛板断裂1例,手术切口皮缘坏死1例,换药后自愈。结论 跟骨外侧入路开放复位可塑形钛板螺钉内固定,必要时植骨术是治疗跟骨骨折的有效方法。  相似文献   
36.
目的:回顾性总结重症心脏瓣膜病置换术体外循环经验.方法:105例重症心脏瓣膜病患者,使用stockerⅢ型心肺机及膜式氧合器,体外循环中采用中度低温,预充白蛋白并附加人工肾超滤,心肌保护用高钾含血停搏液灌注.结果:105例患者均顺利脱机,无1例死亡.体外循环时间60~180 min,主动脉阻断时间60~120 min,所有患者均顺利脱离体外循环,心脏自动复跳86例,电击19例.结论:手术中加强心肌保护,可减低手术后的功能衰竭和并发症,并可有效提高手术成功率.  相似文献   
37.
Anesthesia safety for endoscopic laryngeal laser surgery has been a major limiting factor for laser applications in the larynx and the hypopharynx. Several anesthesia techniques have been proposed and each technique appears to have its own limitations. This paper will deal with the distinct advantages offered by the malleable copper tube which is used for delivery of the open Venturi system anesthesia for endoscopic laser surgery. A retrospective study of 100 patients who have undergone this modality of anesthesia at our institution will be presented. Our conclusion from this study shows clearly the superiority of the copper tube over the conventional aluminium-foil-wrapped endotracheal tube in safety and the exposure of the larynx during surgery.  相似文献   
38.
开放实验室的初步探讨   总被引:5,自引:0,他引:5  
开放实验室是近年来高校实验教学改革的新举措,本文从管理的角度阐述了开放实验室在实验教学改革中对培养学生的实践能力、创新意识、个性化发展等方面发挥的重要作用。从实验时间、实验内容以及仪器设备共享等方面进行了重点讨论。  相似文献   
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内科微创肺减容术的研究进展   总被引:1,自引:0,他引:1  
传统的外科肺减容术治疗慢性阻塞性肺疾病(COPD)有严格的适应证,并且副作用大、并发症多。于是人们研究出多种基于同样原理但是采用内科微创技术的减容方法。目前常用的内科微创肺减容术有使用单向活瓣、生物蛋白胶等封堵支气管使靶肺萎陷、不张,或采用支气管内药物灌注肺泡加封堵使靶肺组织纤维化等。此外,还有人提出人工旁路增加呼出气量的方法。尽管目前还缺少大规模的随机对照临床试验结果,但是内科微创肺减容术已展现了其巨大的临床应用前景,也将为治疗COPD提供更多的选择。  相似文献   
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