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41.
小横切口手术治疗小儿腹股斜疝 总被引:1,自引:1,他引:0
目的:探讨小儿腹股沟斜疝手术方法。方法:经外环小横切口行疝囊高位结扎加修补术。结果:全组126例,平均手术时间12min,无一例出现并发症。结论:此方法有切口小、时间短、创伤轻、恢复快、费用低、疤痕不明显等优点,值得推广。 相似文献
42.
Satoshi Abe 《Journal of orthopaedic science》1997,2(2):75-83
The purpose of this study was to validate the hypothesis of neural histogenesis of Ewing's sarcoma of bone and related tumors
by light microscopic, electron microscopic, and immunohistochemical analysis. We studied 32 round-cell sarcomas (19 cases
of Ewing's sarcoma of bone, 3 extraskeletal Ewing's sarcomas, 5 peripheral primitive neuroectodermal tumors (PNET) and 5 cases
of unclassified small round-cell type of neurogenic sarcoma (NS). Immunoreactivity for MIC2 was observed in all cases of Ewing's
sarcoma and PNET, and in 1 cases of NS. Positive immunoreactivity for neural markers (NSE, synaptophysin, S-100) was found
frequently in some tumors. Ultrastructurally, some specific features of neural differentiation, such as a fragmented basal
lamina and neurosecretory granule-like particles, were found even in typical cases of Ewing's sarcoma of bone, which presented
without a rosette arrangement and were almost negative for neural immuno-markers, but positive for MIC2. These ultrastructural
neural features were observed less frequently in Ewing's sarcoma of bone than in PNET and NS. However, no significant correlation
was demonstrated between the immunoreactivity for neural markers and the ultrastructural and histological neural features.
These results support the hypothesis of a neural origin of Ewing's sarcoma and related neoplasms, and suggest that some overlapping
entity could persist in PNET and Ewing's sarcoma and that this entity could be seen in histological and immunohistochemical
studies of both tumors. 相似文献
43.
M. Nakamura Michitaka Ozaki Shohei Fuchinoue Satoshi Teraoka Kazuo Ota 《Transplant international》1997,10(2):89-95
Ischemia-reperfusion injury by free radicals and lipid peroxides is observed in various organs. Ascorbic acid (AsA) or glutathione
(GSH) in various doses (AsA:2, 0.5, 0.1 mmol/kg, GSH:2 mmol/kg) was intraperitoneally administered to male Wistar rats. The
entire small intestines were resected just before ischemia, after ischemia, and after 20 min of reperfusion (n = 7–10 at each time point). At each time point, the specimens were subjected to assays of lipid peroxides, GSH, and glutaminase
activity of the tissues; they were also examined histologically. In the AsA group, the production of lipid peroxides after
reperfusion was significantly suppressed in a dose-dependent manner, and the ratio of oxidized GSH to total GSH was also significantly
low. Tissue glutaminase activity decreased to a lesser extent, and the degree of injury was apparently less marked in the
AsA group. This study indicates that AsA acts as an antioxidant against peroxidative tissue injury, possibly by scavenging
radicals, preserving reduced GSH, and reducing the peroxidative reaction.
Received: 21 June 1996 Received after revision: 8 October 1996 Accepted: 12 November 1996 相似文献
44.
KETAN A. SHAH SANDRA SHUREY & COLIN J. GREEN 《International journal of experimental pathology》1997,78(5):355-363
Intestinal ischaemia-reperfusion (IR) injury has largely been attributed to cellular necrosis. Apoptosis, a distinct form of cell death has been observed following IR to the brain, heart, adrenals and the kidneys. In order to characterize the role of apoptosis in intestinal IR, small bowel grafts were stored in saline ( n = 6) or modified University of Wisconsin solution ( n = 6) at 4 °C for 12 h and reperfused for 6 h in syngeneic rats. Samples of normal, stored and reperfused intestines at 1, 3 and 6 h were analysed by light and electron microscopy. Following reperfusion, there was crypt and villous epithelial apoptosis, loss of crypt and villous structures, and an increase in mucosal inflammatory cell infiltration. Ongoing apoptosis was maximum at 1 h, its degree decreasing with increasing reperfusion intervals. Large numbers of apoptotic bodies dominated the picture from 3 h of reperfusion. This study has demonstrated the induction of apoptosis by intestinal IR injury, which begins within an hour of reperfusion and is probably responsible for the observed crypt and villous loss. This has potential therapeutic implications as, opposed to necrosis, apoptosis is an active process with genetic regulators and biochemical effectors, which can be specifically targeted to prevent or alleviate IR injury. 相似文献
45.
G. W. McCAUGHAN C-L. SIAH C. ABBOTT J. WICKSON M. BALLESTEROS G. A. BISHOP 《Journal of gastroenterology and hepatology》1993,8(2):142-145
Dipeptidyl peptidase IV (DPP-IV) is a cell surface ectopeptidase that has been implicated in cell-extracellular matrix interactions, lymphocyte growth and the regulation of biological peptides. Previous studies have shown that immunostaining for DPP-IV and DPP-IV enzyme levels is decreased in hepatoma cells and levels have been correlated with the ability of such cells to adhere in vitro. The aim of this paper was to measure DPP-IV enzyme levels in rat hepatoma cells and to examine whether changes were associated with alterations at the mRNA level. The results indicate a greater than 90% reduction in DPP-IV enzyme levels in two rat hepatoma cell lines, HTC and H35, compared with rat hepatocytes. Enzyme levels of the control enzyme leucine aminopeptidase (LAP) were not decreased. mRNA studies indicated that these changes were associated with similar reductions in rat DPP-IV mRNA. It is concluded that DPP-IV is markedly reduced at the protein, enzyme and mRNA levels in rat hepatoma cells. The significance of these changes is unclear but may lead to decreased extracellular matrix interactions by such cells. 相似文献
46.
大鼠肝细胞Ⅰ,Ⅲ型前胶原基因表达及PDGF的影响 总被引:3,自引:1,他引:2
目的观察大鼠肝细胞Ⅰ,Ⅲ型前胶原基因的表达及PDGF对其表达的影响.方法应用原位杂交技术检测分离培养的SD大鼠肝细胞(n=30)内Ⅰ,Ⅲ型前胶原基因的表达.同时观察10μg/L(n=30)和30μg/L(n=30)PDGF促进前胶原基因表达的作用.测定基因表达颗粒总面积占细胞总面积的百分比,并作比较分析.结果无论正常肝细胞或是在两种浓度的PDGF存在时,肝细胞内均可见到Ⅰ,Ⅲ型前胶原基因的表达.正常肝细胞Ⅰ,Ⅲ型前胶原基因表达面积的百分比(%)为77±19和75±21;加10μg/LPDGF后为115±19和112±10,而加30μg/L后为152±34及181±28,且在后者中表达明显增强(P<005及P<001).结论PDGF在转录水平上促进肝细胞胶原的合成. 相似文献
47.
48.
用AGPC法抽提幼年家兔视网膜总RNA,并应用了地高辛标记核酸探针的方法。经斑点杂交显示幼年家兔视网膜出现C—sis原癌基因表达。对实验方法以及C-sis原癌基因表达的意义进行了探讨。认为此方法快速、灵敏,检测C-sis原癌基因表达对深入研究视网膜生长发育及肿瘤等病变有一定意义。 相似文献
49.
用体外培养的人的伪表皮作为模型,进行药物毒理学作用的研究,观察了二甲亚砜(DMSO)在不同浓度和不同接触时间条件下,对人的伪表皮细胞脱氧核糖核酸(DNA)、核糖核酸(RNA)和蛋白质合成的影响:随着接触时间的延长,DNA、RNA和蛋白质合成均受抑制。低浓度条件下(1%),DNA、RNA和蛋白质合成增加;在15~50%浓度下,DNA和蛋白质合成抑制,而RNA合成仍增加;在高浓度条件下(70%~100%),DNA、RNA和蛋白质合成均明显抑制。 相似文献
50.
参附注射液对大鼠缺血再灌注小肠细胞Bax、Bcl-2及c-myc蛋白表达的影响 总被引:9,自引:0,他引:9
目的 探讨参附注射液对大鼠缺血再灌注小肠细胞Bax、Bcl 2及c myc蛋白表达的影响及它们与肠细胞凋亡的内在联系。方法 健康SD大鼠 36只随机分为 3组 ,空白对照组 (S组 )、缺血再灌注 +生理盐水组 (IR +NS组 )、缺血再灌注 +参附注射液组 (IR +SF组 ) ,每组 12只。采用钳闭肠系膜前动脉制备小肠缺血再灌注模型。免疫组化检测Bax、Bcl 2及c myc蛋白的表达 ,每组选 2 4个视野分别测量光密度值 (OD值 )。TUNEL法检测凋亡的小肠细胞并计算凋亡指数。结果 IR +NS组BaxOD值明显高于S组 (P <0 .0 1) ,IR +SF组BaxOD值明显低于IR +NS组 (P <0 .0 1) ,且低于S组 (P <0 .0 5 )。IR +NS组Bcl 2OD值高于S组 (P <0 .0 5 ) ,且IR +SF组Bcl 2OD值高于S组 (P <0 .0 1) ,但IR +NS组与IR +SF组比较无显著差异。IR +NS组c mycOD值明显高于S组 (P<0 .0 1) ,且明显高于IR +SF组 (P <0 .0 1)。IR +NS组细胞凋亡指数明显高于S组和IR +SF组 (P <0 .0 1) ,而IR +SF组高于S组 (P <0 .0 5 )。结论 参附注射液增加小肠组织Bcl 2蛋白的表达 ,降低Bax及c myc蛋白的表达 ,抑制小肠细胞凋亡 ,保护缺血再灌注小肠。 相似文献