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21.
丙型肝炎(HC)86例,经临床观察发现其临床特点是:①潜伏期长短不一,长者120d短者26d,平均40.5±14.5d。②起病缓慢而隐匿。③病状轻,体征不明显,病程长。④肝功能损害程度与症状、体征不一致,往往不能及时诊治。⑤肝功能恢复慢,ALT、AST有持续升高或反复异常。⑥治疗:用治疗肝炎的常用药物仅对改善症状有一定作用,对缩短病程及肝功能恢复无效。  相似文献   
22.
目的:探讨线粒体呼吸链细胞色素C氧化酶(COX)活性异常在老年性聋发病中的作用机制.方法:免疫组化法检测老年性聋大鼠耳蜗COX活性.结果:与正常对照组相比,实验组老年性聋大鼠耳蜗中COX活性降低.结论:耳蜗组织中COX活性降低在老年性聋的发病中起一定作用.  相似文献   
23.
Mixed mesodermal tumors and carcinosarcomas of the uterus are classified as sarcomas. However, in other sites, malignant biphasic tumors may be classified as carcinomas, mesotheliomas, or sarcomas. In order to clarify their behavior and patterns of differentiation, we performed a clinicopathologic and immunohistochemical study of 22 cases aimed at analyzing the pattern of spread and histologic appearance of the metastasis, as well as the distribution of intermediate filaments in the primary tumor and the metastasis. Four monoclonal antibodies (Mabs) were used to detect epithelial lineage, three that recognize keratin (AE1/AE3, CAM5.2, MAK6) and one that recognizes epithelial membrane antigen (EMA). A Mab against vimentin was also used. Metastases involved the omentum, pelvic peritoneum, ovaries, fallopian tubes, pelvic or para-aortic lymph nodes, liver parenchyma, and tonsil. These metastases were composed of carcinoma only. Lymphatic/vascular invasion was identified in 11 cases; it consisted exclusively of carcinoma. In all 12 cases evaluated immunohistochemically, keratin and EMA were identified in the majority of the cells in the epithelial component and in a more focal distribution in the spindle cell component in 11 (92%). Vimentin was detected in the majority of spindle cells in nine cases (75%) and in a more focal distribution in the epithelial component in six cases (50%). In the spindle cell component, keratin and EMA were present in widely scattered individual spindle-shaped and rounded cells, within solid clusters of rounded cells, and in nests of cells with small lumens. The distribution of keratin, EMA, and vimentin in the metastases (carcinoma in all instances) was similar to the epithelial component in the primary tumor. Our findings indicate that the epithelial component of these tumors invades lymphatic/vascular spaces and metastasizes, whereas the spindle cell component has limited metastatic potential, if any. Since the behavior of these neoplasms is dictated by the epithelial element, we believe that mixed mesodermal tumors of the uterus should be classified as carcinomas rather than sarcomas.  相似文献   
24.
甲氧基红霉素对卡马西平药物动力学的影响   总被引:2,自引:0,他引:2  
应用荧光偏振免疫法,测定6只家兔po卡马西平及连续多次po用搓甲氧基红霉素后po卡马西平的血清卡马西平浓度,用3p87程序包按二室模型对数据进行处理并进行统计学分析。  相似文献   
25.
Reactive gliosis is an aspect of neural plasticity and growth factor (GF) stimulation of astrocytes in vitro is widely regarded as a model system to study astrocyte plasticity. Astrocytes express receptors for several ligands including lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P), agonists for the G-protein-coupled lysophospholipid receptors (lpRs). Activation of lpRs by LPA or S1P leads to multiple pharmacological effects including the influx of calcium, phosphoinositide (PI) hydrolysis, phosphorylation of extracellular receptor regulated kinase (ERK), release of arachidonic acid, and induces mitogenesis. Treatment of astrocytes in vitro with a growth factor cocktail (containing epidermal growth factor [EGF], basic fibroblast growth factor [bFGF] and insulin) led to a marked attenuation of lpR-induced PI hydrolysis. In contrast, under identical conditions, GF treatment led to marked potentiation of PI hydrolysis downstream of activation of another abundantly expressed G-protein coupled receptor, mGluR5. Quantitative gene expression analysis of GF-treated or control astrocytes by TaqMan RT-PCR indicated that GF treatment did not change gene expression of lpa1 and s1p1, but increased gene expression of s1p5 which is expressed at very low levels in basal conditions. These results suggest that GF differentially affected PLC activation downstream of mGluR5 versus lpR activation and that the changes in mRNA levels of lpRs do not account for marked attenuation of agonist-induced phosphoinositide turnover.  相似文献   
26.
Hemoperitoneum secondary to rupture of cystic artery pseudoaneurysm   总被引:1,自引:0,他引:1  
BACKGROUND:Spontaneous hemoperitoneum of hepato- biliary origin is commonly due to hemorrhage from a liver tumor.It is rarely caused by spontaneous rupture of aneurysm in visceral arteries. METHODS:We report an unusual case of hemoperitoneum caused by rupture of cystic artery pseudoaneurysm,and also outline the approach to its management through surgical and radiological methods. RESULTS:In our patient,the pseudoanurysm was initially treated with percutaneous thrombin injection.However this method of treatment failed after initial success.The pseudoanurysm was finally obliterated successfully using microcoil embolization. CONCLUSIONS:The mainstay of treatment of cystic artery pseudoaneurysm is cholecystectomy and ligation of the aneurysm.Recent publications showed success in using microcoil embolisation.In this case we also outline the use of percutaneous thrombin injection as a definitive treatment method and discuss its success or failure as a new method of treatment.  相似文献   
27.
目的:观察糖基化终末产物(AGEs)对大鼠肾系膜细胞纤溶酶原激活物抑制物-1(PAI-1)表达的影响及其与细胞外基质(ECM)成分含量的关系。方法:体外培养正常大鼠肾系膜细胞,分别用糖化牛血清白蛋白(AGEs)及未经糖化的牛血清白蛋白(BSA)处理,以常规培养的肾系膜细胞作为对照,检测不同时间、不同浓度AGEs对纤维连接蛋白(FN)、Ⅳ型胶原、PAI-1表达的影响。MTT法检测AGEs对系膜细胞增殖的作用,ELISA测定条件培养基中FN、Ⅳ型胶原及PAI-1蛋白含量,逆转录聚合酶链式反应(RT—PCR)检测系膜细胞PAI-1 mRNA的表达。结果:与相应浓度的BSA比较,AGEs(0—200mg/L)对系膜细胞增殖无明显影响,但可不同程度地刺激系膜细胞FN、Ⅳ型胶原、PAI-1蛋白的产生。RT—PCR检测显示,给予AGEs(100mg/L)的系膜细胞PAI-1 mRNA的表达明显增加(P〈0.01)。结论:AGEs促进系膜细胞PAI—1的表达,提示AGEs通过上调PAI-1的表达而减少细胞外基质降解,可能是糖尿病肾病细胞外基质积聚的原因之一。  相似文献   
28.
A 25-year-old female has had brown to erythematous telangiectatic patches and grouped papules on her face, neck, arm, and trunk since childhood following B.C.G. vaccination. Histopathologically, the lesions consisted of hyperkeratosis, slight acanthosis, tuberculoid granulomas with some Langerhans type giant cells in the mid-dermis. Although various forms of cutaneous tuberculosis after B.C.G. vaccination have been reported, it was difficult for us to assign the patient's skin lesion to any specific disease entity. Remission of her cutaneous lesions occurred clinically and histopathologically after treatment with isoniazid and rifampin.  相似文献   
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30.
经尿道膀胱肿瘤切除专用手术刀具的临床应用   总被引:4,自引:0,他引:4  
目的对经尿道膀胱肿瘤切除专用手术刀具治疗浅表性膀胱肿瘤进行临床应用评价。方法在传统电切刀的远端添加保护襻组成膀胱肿瘤切除专用手术刀具。使用该种手术刀具治疗浅表性膀胱肿瘤48例,使用方法与普通电切刀近似。男26例,女22例。年龄23~76岁,平均43岁。肿瘤分期Tis者1例,T0~T1者47例。肿瘤分级G1~G2者36例,G3~G4者12例。瘤体直径0.5~8.0 cm。肿瘤位于膀胱顶部4例,左侧壁11例,右侧壁9例,前壁4例,后壁13例,颈部7例。肿瘤单发31例,多发17例。术后常规卡介苗膀胱灌注1年,每3个月行膀胱镜检查1次。结果48例平均手术时间(23±10)m in。术中18例(37.5%)发生闭孔神经反射,未出现膀胱穿孔病例;无瘤体后部的正常膀胱黏膜误切。46例术后随访1年,14例复发,均为远位新生膀胱肿瘤,术后3个月时发现1例,4~6个月时3例,7~9个月时6例,10~12个月时4例。结论使用该专用手术刀具治疗浅表性膀胱肿瘤容易控制切除深度,可最大限度地避免膀胱穿孔,并可保护大体积肿瘤后部盲区的正常黏膜以免误切。  相似文献   
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