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61.
Laparoscopic nephrectomy was performed in 15 male pigs, the procedure was successful in 14. Extraction of the intact kidney through a 5-cm lower abdomen incision was done in 7 animals; complete destruction and evacuation of the kidney was accomplished by a round-knife suction device through a 1-cm port in another 7 pigs. Grossly, the specimen consisted of sausage-like tubular renal tissue and a small amount of tissue debris. Pathology revealed that the glomerular and tubular structures were well preserved, no interstitial hematoma could be found. Four ports were usually used, one 1-cm umbilical camera port, one 0.5-cm port for ureter traction, and two 1-cm working ports along the midclavicular line. All the pigs recovered uneventfully. The average operation time was 3 h 20 min. The application of endo-GIA (United States Surgical Corporation) for renal hilum reduced the operative time to 2 h 20 min. Complications included renal vein tear during endoclip application and cutting in the first case, mild subcutaneous emphysema in 2 cases. This first pig received exploratory laparotomy for the repair and ligation of the renal vein. No more major complications occurred with increasing experience. From this porcine experiment, we conclude that the combination of laparoscopy, a tissue destroyer and an endobag for the entrapment of kidney seem to be a promising technique for clinical nephrectomy.  相似文献   
62.
目的研究一种新发现的抗氧化蛋白质--凋亡敏感基因(SAG)在短暂性缺氧再复氧复注血清诱导的细胞坏死和凋亡中的作用.方法用短暂性缺氧再复氧复注血清来诱导原代培养的大鼠大脑皮质星形胶质细胞损伤,用免疫细胞化学方法检测凋亡敏感基因的表达,并作图像分析;用流式细胞仪检测胶质细胞在短暂缺氧再复氧复注血清后不同时间点的凋亡率.结果凋亡敏感基因在缺氧15 min再复氧复注血清5 h后表达最高,在复氧复注血清16 h后恢复至对照组水平;细胞凋亡率在缺氧15 min再复氧复注血清1h时达到最高,而在再复氧复注血清5 h后降至对照组水平.结论凋亡敏感基因具有抗凋亡的作用,可减轻星形胶质细胞的缺血再灌注损伤.  相似文献   
63.
Subjects discriminated whether two sequentially presented human face pictures (S1 and S2) were identical while event-related potentials were recorded to explore the neural basis of visual completion for occluded objects. Four kinds of stimulus trials were employed: S2 and S1 were identical (match-complete); S2 and S1 were identical, but S2 was partially occluded (match-incomplete); S2 was a different face from S1 (mismatch-complete); S2 was different from S1, and was partially occluded (mismatch-incomplete). Incomplete faces enhanced the amplitude of N1 compared with complete faces. The peak latency of N2 elicited by incomplete faces was delayed about 20 ms compared with complete faces. The enhancement of N1 is related to visual completion processing that requires additional time.  相似文献   
64.
65.
A complete randomized block design was used to compare the binding kinetics of cholera toxin to developing rat enterocyte microvillus membranes prepared from newborn, 2-week-old, 4-week-old, and adult animals. Saturation-binding isotherms were generated on 16 independent samples (four blocks) under steady-state and reversible conditions. Scatchard analyses suggested positive cooperative binding to a single class of receptors, and the isotherms were analyzed by both the Hill-Waud and Michaelis-Menten functions. Receptor density varied significantly with age (P = 0.013). An abrupt rise in receptor density occurred after the neonatal period and normalized in the adult animal. The half-dissociation constant also varied significantly with age (P = 0.019). Microvillus membranes from suckling animals had a slightly higher apparent affinity than those from weaned animals. Neither receptor concentration nor membrane purity confounded these observations. Whereas age-related changes in apparent affinity correlated with cellular responses, changes in receptor density did not. This study suggests that developmental changes in membrane structure which influence binding affinity but not receptor density may, in part, contribute to the increased sensitivity of suckling rats to cholera toxin exposure.  相似文献   
66.
Rat hemoglobins are unusually heterogeneous among mammals. This heterogeneity provides multiple opportunities for asynchronies in synthesis and degradation. We have examined rat hemoglobin turnover after an intravenous injection of 2-14C-glycine. After analyzing incorporation into the seven nonallelic globin chains of adult rats, we found the percentage of the major beta chain decreases over the red cell lifespan while the percentage of one of the minor beta chains increases. This suggests that a post-synthetic modification event converts a portion of the latter into the former.  相似文献   
67.
Regional cerebral blood flow was studied in 7 patients with clinically suspected Alzheimer's disease and 10 normal controls by single photon computed emission tomography (SPECT) using HM-PAO. All patients with Alzheimer's disease and no controls had parietal lobe hypoperfusion which was usually bilateral. In patients with more severe dementia hypoperfusion extended into the frontal lobes. Parietal lobe hypoperfusion corresponds to parietal lobe degeneration which is the one of the first neocortical regions to show the typical degenerative changes of Alzheimer's disease. SPECT with HM-PAO is a non-invasive investigation available in most nuclear medicine departments and complements existing tests in the routine evaluation of patients presenting with dementia.  相似文献   
68.
A simple, rapid, and accurate method for measuring limb-length discrepancies with computerized axial tomographic equipment is described. With this method less irradiation is delivered and some of the errors of computation are eliminated, compared with conventional methods. The costs of the technique are comparable with those of scanograms. The method is particularly applicable in the patient who has contracture of a joint.  相似文献   
69.
S Law  M Fok  K M Chu    J Wong 《Annals of surgery》1997,226(2):169-173
OBJECTIVE: The objective of this study was to compare the hand-sewn and stapled methods in esophagogastric anastomosis. SUMMARY BACKGROUND DATA: After esophageal resection for cancer, the relative merits of the hand-sewn and the stapled methods of esophagogastric anastomosis, especially regarding leakage and stricture rates, have not adequately been studied. METHODS: A prospective randomized controlled trial was undertaken in 122 patients with squamous cell cancer of the thoracic esophagus who underwent a Lewis-Tanner esophagectomy. Patients were stratified according to esophageal size, based on the diameter of the divided esophagus (< or > or = 30 mm) and then were randomized to have either a hand-sewn or a stapled anastomosis. RESULTS: The mean total operating times (standard error of the mean) when the hand-sewn and the stapled methods were used were 214 (4) minutes and 217 (3.4) minutes, respectively (p = not significant [NS]). The respective in vivo proximal resection margins (standard error of the mean) were 8 (0.4) cm and 7.6 (0.4) cm (p = NS). Leakage rates were 1.6% and 4.9% (p = NS). Excluding hospital deaths, patients with leakage or anastomotic recurrence, and those who received radiation therapy to histologically infiltrated resection margin, anastomotic stricture was found in 5 (9.1%) of 55 patients in the hand-sewn group and 20 (40%) of 50 in the stapler group (p = 0.0003). The difference in stricture rates was significant in small as well as large esophagi. Anastomotic recurrence developed in only one patient in each group. CONCLUSIONS: The authors conclude that both methods were safe, but the stapled technique resulted in more stricture formation.  相似文献   
70.
目的:介绍65例颅内肿瘤显微外科手术治疗经验;方法:本组患者65例,根据肿瘤部位、大小、性质,选择合适的手术入路,采用显微手术切除肿瘤;结果:全切53例,部分切除12例,无手术死亡;术后并发视神经麻痹1例,面神经并动眼神经麻痹1例,三叉神经麻痹1例,舌咽神经麻痹1例,偏瘫5例,无其他手术并发症;结论:正确的手术思路、合适的手术入路是手术成功的基础;采用显微外科手术技术是提高全切率、减少并发症的关键。  相似文献   
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