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141.
探查乳腺肿瘤组织中Ⅰ型纤溶酶原激活物抑制剂(PAI-1)的表达,并比较乳腺恶性肿瘤组织与良性纤继腺瘤及正常组织中PAI-1的差异。用免疫组织化学和原位杂交的方法,确定了乳腺癌、乳腺纤维腺瘤及瘤旁正常组织中PAI-1的分布;用发色底物法检测组织提取液中PAI-1的活性;用图象分析的方法对组织切片上的PAI-1进行灰度定量。结果:PAI-1主要分布在乳腺正常腺上皮细胞、瘤上皮细胞和腺癌细胞的胞浆中,但恶性组织中的成纤维细胞、巨噬细胞以及癌旁纤维组织也有染色。癌组织中PAI-1的活性(P<0.001)和含量(P<0.005)均高于良性乳腺纤维腺瘤及瘤旁正常组织。结论:PAI-1在乳腺恶性肿瘤组织中明显升高,PAI-1的检测可能为临床乳腺肿瘤的诊断、预后提供新的指标。  相似文献   
142.
BACKGROUND: Although 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), a product of 15-lipoxygenase (15-LO), may be involved in mild to moderate asthma, little is known about its potential roles in severe asthma. OBJECTIVES: This study was performed to evaluate 15(S)-HETE levels in bronchoalveolar lavage fluid (BALF) from severe asthmatics with and without airway eosinophils and from the control groups. In addition, 15-LO protein expression was examined in endobronchial biopsy, while its expression and activation were evaluated in BAL cells. RESULTS: While 15(S)-HETE levels in BALF were significantly higher in all severe asthmatics than normal subjects, severe asthmatics with airway eosinophils had the highest levels compared with mild, moderate asthmatics and normal subjects. 15(S)-HETE levels were associated with tissue eosinophil numbers, sub-basement membrane thickness and BALF tissue inhibitor of metalloproteinase-1 levels, and were accompanied by increased 15-LO expression in bronchial epithelium. In addition, activation of 15-LO was suggested by the increased proportion of 15-LO in the cytoplasmic membrane of alveolar macrophages from severe asthmatics. CONCLUSION: The data suggest that severe asthmatics with persistent airway eosinophils manifest high levels of 15(S)-HETE in BALF, which may be associated with airway fibrosis. It is likely that 15-LO expression and activation by airway cells explain the increased 15(S)-HETE levels.  相似文献   
143.
目的:探讨脑外科手术后部分患者病变邻近脑组织发生正常灌注压突破并发症的发病机制及其超微病理基础.材料和方法:对68例脑内血管畸形病变邻近的脑组织进行电子显微镜观察.结果:病灶邻近脑组织内部分毛细血管外周的星形细胞足突缺失或出现血管基膜疏松、分层等发育不良的情况,甚至有些血管壁组织结构破损.结论:电子显微镜检查证实,在血管畸形病灶周围的脑组织内可见病理性血管.该血管的基膜发生病变,血管周围的星形细胞足突明显减少或破坏.当血液灌注压力突然变化时,这种病变的血管就可能发生液体外渗及破裂.这就是在神经外科手术中或手术后发生正常灌注压突破并发症的超微病理基础.  相似文献   
144.
周围神经损伤后勃起功能障碍的治疗进展   总被引:3,自引:0,他引:3  
外伤、手术可因盆神经丛和 (或 )海绵体神经损伤而造成勃起功能障碍。较理想的治疗方法是使损伤神经自我再生修复 ,完全恢复勃起功能。本文综述近年来勃起神经损伤后再生修复方面的研究进展 ,试图寻找出一种促进损伤的勃起神经再生的最佳方法  相似文献   
145.
早期高血压主动脉单核细胞趋化因子—1的表达   总被引:3,自引:0,他引:3  
目的:探讨高血压早期主动脉壁单核细胞趋化因子-1(MCP—1)的表达。方法:用原位杂交和RT—PCR方法检测急性期两肾一夹(2KIC)高血压大鼠在血压升高不同时间主动脉壁MCP—1的表达。结果:正常血压大鼠主动脉壁无MCP—1的表达;在2K1C大最高血压形成一周,主动脉壁MCP—1即有表达,并随时间延长,其表达持续增加。结论:提示高血压早期即有主动脉壁MCP—1的表达,并随时间延长增加,这可能与其加速动脉粥样硬化形成有关。  相似文献   
146.
This study was undertaken to determine if PG490-88 and tacrolimus (Tac) act synergistically to prevent renal allograft rejection in monkeys and to explore possible mechanisms of synergy between these agents. MHC-mismatched renal allografts were transplanted into cynomolgus monkeys after bilateral nephrectomy. Recipients were divided into the following groups: (i) no treatment; (ii) PG490-88 (0.03 mg/kg); (iii) Tac (1 mg/kg); (iv) PG490-88 (0.01 mg/kg) + Tac (1 mg/kg) and (v) PG490-88 (0.03 mg/kg) + Tac (1 mg/kg). Through synergy PG490-88 and Tac inhibited anti-CD3/PMA-induced T-cell proliferation and IFN-gamma expression in vitro. Tac monotherapy only marginally prolonged survival (27 +/- 3.2 days), while the combination of PG490-88 and Tac significantly prolonged graft survival to a median of 99 days (PG490-88 at 0.03 mg) and 38.5 days (PG490-88 at 0.01 mg/kg). Prolonged survival correlated with inhibited IgM production as well as reduced T-cell infiltration, IL-2 protein expression and NF-AT/NF-kappaB activity. We conclude that PG490-88 and a subtherapeutic dose of Tac significantly prolong renal allograft survival in monkeys through the synergistic inhibition of T-cell activation and a decrease in IFN-gamma production and NF-AT/NF-kappaB activity.  相似文献   
147.
教师常常偏爱成绩好的学生,而对学习困难学生则在情感上、精力上和研究上投入不够。对学习困难学生的认识往往集中在他们身上的缺陷,而忽视了他们具有的学习潜能。教学实践证明,合理的施教是开发其潜能、促进其转化的关键。  相似文献   
148.
The effects of zymosan-activated plasma(ZAP)on lung fluid exchangeand on superoxide anion production by granulocytes were studied in 8 consciousgoats with chronic lung lymph fistula,It was found that after ZAP infusion, thecirculating granulocytes were activated and the release of superoxide anions wasmarkedly enhanced. There was an increase in lung lymph flow and proteinconcentration.It suggests that the superoxide anion released by the stimulatedgranulocytes can play a role in inducing lung injury by the activated complement.  相似文献   
149.
用单光子吸收法对足月孕妇尺、桡骨骨矿物质含量(BMC)、骨面密度(BMC/BW)进行测定及作血清钙、磷的生化测定。结果显示:足月孕妇的尺、桡骨骨矿物质含量、骨面密度明显低于同年龄组的未孕妇女。主要因为妊娠胎儿的骨胳生长发育,需要孕妇向胎儿输送大量的钙离子,若母亲对钙摄入不足或吸收不良,则造成孕妇的骨矿物质含量降低,骨质疏松;而孕妇血清钙、磷降低不明显。  相似文献   
150.
A C Wang  S Hsueh  C F Sun 《台湾医志》1992,91(11):1054-1058
This paper reports the treatment results of 50 symptomatic females who had clinical features of squamous papillae and histologic evidence of koilocytosis. Either a carbon dioxide laser or a single application of trichloroacetic acid (TCA) was used to treat these patients. All of the patients were alternately and prospectively randomized into one of two groups. Twenty-three of the 25 women treated by laser and 10 of the 25 women treated by TCA had resolution of either the symptoms or the vulvar lesions in a follow-up period ranging from six to 22 months. Hence, we were able to control the symptoms and lesions in 92% of the women following initial laser treatment and 40% of the women following a single application of TCA. In addition, cosmetic results were satisfactory, and complications were minimal in the laser-treated group of patients. However, human papillomavirus DNA was still detected three to four weeks after treatment in 24% of the women treated by laser and 64% of the women treated by TCA. Whether they are at a higher risk of recurrence as compared to those without detectable viral DNA remains to be determined.  相似文献   
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