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91.
Long-term results of bariatric surgery are reviewed. The weight criteria for patient acceptance for bariatric surgery and their variation are presented graphically and discussed. Factors affecting patient selection in an attempt to improve outcome results in the small group of patients who currently achieve less weight loss than anticipated are defined. An attempt is made to define pre-operative criteria for selection of pure restrictive versus combined restrictive and malabsorptive procedures. Aspects of motivation, co-morbidity, age and pre-operative weight are discussed and the position statement of the ASBS in regard to laparoscopic bariatric surgery is defined.  相似文献   
92.
Mason EE 《Obesity surgery》1996,6(3):218-223
BACKGROUND: Have surgeons in North America accepted operations for the treatment of severe obesity? This question was posed by organizers of the Ninth International Symposium on Obesity Surgery that met in Stockholm in September, 1995. Study design: In order to obtain opinions which might help to answer the question posed, a 1-page questionnaire was sent to 151 chairmen of academic departments of surgery in North America in December 1994 asking about the acceptance and use of surgical operations for the treatment of severe obesity. RESULTS: Answers, received from 112 or 74%, indicated that operative treatment should be used (74%), was effective (77%) and safe (71 %). However, only 65% of departments provided such operations. Operative treatment for obesity was available outside the department in 53%. The operations most frequently used were Roux-en-Y gastric bypass (RGB) and vertical banded gastroplasty (VBG). A single operation was offered by 44 departments and a choice of two or more operations in 30 departments. RGB and VBG were equally in use. Gastric banding was used as an alternative to VBG in six departments. Other operations were in use in six departments either alone (three) or as alternatives to RGB and VBG (three). CONCLUSIONS: It appears that surgical treatment of obesity is accepted and available in the majority of academic departments of surgery.  相似文献   
93.
A previously published study reporting the use of a modifiedswim-up technique for sperm preparation prior to inseminationwhich resulted in a high percentage of male births has beencriticized for its lack of controls. The present prospectivestudy was initiated to investigate further the efficacy of modifiedswim-up preparation for male sex-selection when applied in aproperly defined control group. Our results showed that theproportion of males born in singleton pregnancies was 50% inthe group inseminated following sperm preparation with Percolland in the control group with no sperm preparation comparedwith 88.5% in the group treated with the modified method ofswim-up sperm preparation prior to insemination. This high rateof males in the group treated with modified swim-up was alsoobserved in singleton pregnancies of women taking ovulationinducing drugs (primarily clomiphene citrate). This contrastswith previous publications in which a higher rate of femaleswas found in clomiphene citrate patients using the albumin separationtechnique. How the mechanism of the swim-up procedure may resultin a high male birth rate remains unclear. A high percentageof y enriched semen was found using fluorochrome quinacrinemustard staining but this procedure may falsely stain autosomalchromosomes. If analysis using sensitive DNA probes fails toconfirm the y enrichment of the spermatozoa, one must hypothesizethat the modified swim-up procedure damages the x-spermatozoa.  相似文献   
94.
螺旋霉素高产株的推理选育和工业生产   总被引:4,自引:1,他引:4  
产二素链霉菌SIPI9004经自发或诱发的突变和推理选育,得到若干耐药性变种。第六代一株变种10-29,产生螺旋霉素比原始菌株SIPI9004增产约6倍。该变种应用于工业生产(30m^3发酵罐),发酵效价、总单位和指数三项指标比原来生产菌株F-16分别提高26.1%、33.3%和26.8%。  相似文献   
95.
OBJECTIVE: Although most methods for selecting the sex of offspring by sorting spermatozoa are ineffective at shifting the ratio of Y- to X-containing cells, some commercial sources continue to offer such services. Our objective was to evaluate commercially “sorted” samples with use of dual-color fluorescence in situ hybridization and to identify variations in assessment by comparing motile and total sperm populations, donors, observers, and fluorescence in situ hybridization probes.STUDY DESIGN: Cryopreserved sperm from seven anonymous donors were processed as for insemination. Sperm cells from each total sample or motile subfraction were prepared for fluorescence in situ hybridization by incubation with disulfide-reducing agents to expand sperm nuclei. Two sets of X and Y chromosome–specific, fluorophore-labeled deoxyribonucleic acid probes were used. At least 400 nuclei from each preparation were classified independently by three blinded observers. Hybridization efficiency, aneuploidy, and sex chromosome content were evaluated in subsets of five unsorted, five female-oriented, and five male-oriented samples. Total and motile subfractions were compared with eight samples. Fluorescence in situ hybridization probes were compared in five paired unsorted samples.RESULTS: No differences were detected between washed samples and paired motile subfractions. No differences in hybridization and aneuploidy were detected between groups of sorted samples. The Y/X ratio was significantly different between the sorted groups. However, male-oriented samples had a lower Y/X ratio than female-oriented samples did. Observer and probe choice accounted for small but significant variations that did not alter conclusions about the Y/X ratio for sorted samples.CONCLUSION: In a series of 10 sorted samples from one commercial source, dual-color fluorescence in situ hybridization demonstrated a small but significant shift in the sex chromosome ratios among samples. However, this shift was opposite to that expected by the orientation of the sorted samples. (Am J Obstet Gynecol 1997;176:1172-80.)  相似文献   
96.
抗前列腺癌细胞特异抗体库的构建及特异结合抗体的筛选   总被引:1,自引:2,他引:1  
目的: 获得前列腺癌的噬菌体呈现型单链抗体库,筛选与前列腺癌特异结合的抗体,为前列腺癌的诊断和治疗奠定基础. 方法: 用两种恶性程度较高的前列腺癌细胞PC3,DU145膜蛋白混合物免疫Balb/c小鼠.取脾脏提取总RNA,用RT-PCR分别扩增抗体重、轻链可变区基因(VH和VL), 经Linker连接形成ScFv基因片段,将ScFv基因片段与噬菌粒载体pCANTAB 5E的连接产物转化大肠杆菌TG1.用辅助噬菌体M13KO7进行超感染,获得重组噬菌体抗体.以恶性程度低的前列腺癌细胞LNCap为对照,用PC3细胞对重组噬菌体抗体库进行五轮筛选后,随机挑取克隆,经phage-ELISA筛选特异性结合PC3细胞的ScFv.结果: 用所构建的库容量为3.5×106的单链抗体库筛选特异结合抗体,得到一个与PC3细胞特异结合的噬菌体-单链抗体.结论: 本研究所构建的抗体库中可筛选到与前列腺癌细胞结合特异性较好的抗体,可用于前列腺癌的诊断和治疗中.  相似文献   
97.
陈明  顾幸生  赵瑾 《医学教育探索》2006,(5):596-600611
提出了一种改进的自适应遗传算法,在选择算子中引入裂变选择的思想,避免种群中超级个体的出现,维持了种群的多样性。该算法改造了交叉算子和变异算子,提高了算法的收敛速度,避免早熟。同时,提出了在宗族中构造子代种群的思想,提高了算法的寻优效率。仿真函数优化的结果验证了该算法能有效地维持种群的多样性并迅速找到最优解。  相似文献   
98.
郑大喜 《卫生软科学》2006,20(5):487-489
在医学诊疗过程中,医患双方存在着医疗信息分布和掌握的不对称,这种情况直接影响着医患信任的建立和患者对医疗效果的评价.本文从经济学视角探讨了减少医患信息不对称程度,构建和谐医患关系的设想.  相似文献   
99.
肝苏缓释胶囊精制工艺中大孔吸附树脂型号的筛选   总被引:1,自引:1,他引:1  
目的筛选适合分离纯化赶黄草提取物的最佳大孔吸附树脂型号。方法以槲皮素吸附量、解吸率、吸附速率及解吸速率为指标,对D140、D141、D3520、AB-8、D101、DM-130、NKA-9、S-8等8种大孔吸附树脂的性能进行比较。结果8种大孔吸附树脂对槲皮素的静态吸附量顺序为:D140>D141>D3520>AB-8>D101>DM-130>NKA-9>S-8,解吸率顺序为:D140>D141>S-8>AB-8>NKA-9>D3520>DM-130>D101。其中D140、D141对槲皮素的吸附量分别为9.728、.76m.g-1,解吸率分别为88.5%、84.3%;吸附速率和解吸速率比较结果表明,D140型树脂在加入药液后约5h吸附达到平衡,在加入解吸剂后1.5h解吸完全,其吸附、解吸速率最快。结论在8种树脂中,D140的吸附与解吸效果最佳。  相似文献   
100.
孙健  单秋华  陈新勇 《中国针灸》2005,25(9):633-635
目的:探讨针刺经穴(风池、天柱)、夹脊(C4~C6)对椎-基底动脉供血不足(VBI)的协同或拮抗作用.方法:采用自身对照的方法,对20例VBI患者分3次分别观察针刺经穴组、夹脊组、配伍组3个穴组对椎-基底动脉收缩期血流速度(vsys)的影响.结果:3组针刺后椎-基底动脉的vsys较针刺前相比均有显著性提高(P<0.05,P<0.01),但3组之间比较差异无显著性意义(P>0.05).结论:针刺风池、天柱或C4~C6夹脊组或两者同用,均可使VBI患者椎-基底动脉的vsys值升高,改善椎-基底动脉的供血状况.但从即刻改善程度来说,两者之间未发现协同或拮抗作用.  相似文献   
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