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71.
The chick chorioallantoic membrane was used to determine whether the carotid atherosclerotic plaque stimulates angiogenesis. Carotid endarterectomy specimens (1 mm3) with fibromuscular plaque (n = 8) and complicated plaque (n = 11) were implanted on the membrane on day nine of incubation and the response evaluated on day 11. Following fixation in situ with 10% formalin the angiogenic response was evaluated by: (1) examining whole membrane mounts, (2) quantitatively from a vascular density index and (3) from a histological study. Unmanipulated chorioallantoic membrane (n = 11) and plaque boiled prior to implantation (n = 6) served as controls. The vascularity of whole mounts of both fibromuscular and complicated plaque was greater than the controls. Vessel density of the membrane was estimated by counting the number of vessels intersecting four concentric circles (144.5 mm total circumference) placed on the formalin fixed membrane. The vascular density index due to the fibromuscular plaque (390.6 +/- 8.3) and complicated plaque (391.0 +/- 14.9) were similar (P greater than 0.9) but were significantly greater (P less than 0.001) than the unmanipulated membrane (327.9 +/- 5.6) or after treatment with the boiled plaque (283.8 +/- 15.6). Transforming growth factor beta 1 confirmed the validity of the experimental model to study angiogenesis. The histology of the chorioallantoic membrane due to either type of plaque was similar. Numerous vessels surrounded the plaque, and intraplaque vessels containing nucleated chick erythrocytes were observed. Although scattered vessels surrounded the boiled plaque, intraplaque vessels were not observed. This study demonstrates that the atherosclerotic plaque has angiogenic properties that may account for the increase in vasa vasorum that is associated with the plaque.  相似文献   
72.
The role of human spumaretrovirus (HSRV) infections in the pathogenesis of multiple sclerosis (MS) was investigated with recombinant HSRV env-specific enzyme-linked immunosorbent assay. The presence of HSRV antibodies was determined in pairs of serum and cerebrospinal fluid (CSF) samples from 60 MS patients. In 7 of these patients serial serum and CSF samples were obtained in relation to the clinical activity of the disease during a period of 2 years. No increased antibody reactivity was demonstrable in the MS population compared with 14 aseptic meningitis patients, 50 blood donors and 16 healthy controls. Slightly elevated levels of antibodies were demonstrable in serum and/or CSF in 4 MS patients but also in 1 patient with aseptic meningitis, 1 blood donor and 1 child. No marked serum or CSF HSRV antibody fluctuation was observed in the MS patients followed longitudinally. Thus, this study does not support the involvement of HSRV in the pathogenesis of MS.  相似文献   
73.
原发性胃肠道粘膜相关淋巴组织淋巴瘤47例临床病理分析   总被引:1,自引:0,他引:1  
唐波  彭志红  姜军 《重庆医学》2003,32(11):1510-1512
目的 探讨原发性胃肠道粘膜相关淋巴组织淋巴瘤(GIL-MALT)的临床病理特点。方法 回顾性分析1990~2000年我院经手术及病理证实的47例胃肠道MALT患者临床病理资料。结果 47例患者平均年龄57.2岁,男女比例2.1:1。以腹痛和发热为主。病变分布为胃32例,小肠4例,回盲部及盲肠5例,大肠6例。内窥镜下息内型15例,溃疡型25例,弥漫型7例。除1例为T细胞淋巴瘤,其余均为B细胞淋巴瘤。结论 胃肠道粘膜相关淋巴瘤以中老年为主,男性居多,临床误诊率较高。内窥镜下多次多点活检、深凿活检可提高本病的确诊率。  相似文献   
74.
In a prospective multicenter study of 1,052 patients with clinical signs of a scaphoid fracture, mammo-graphic films and fine intensifying screens were used at the radiographic examination. 5 standardized projections including 3 special projections focused on the scaphoid were taken. 150 fractures were diagnosed at the first examination but in 10 cases the fracture was first diagnosed at a second radiographic examination after 10-14 days.

The second examination still seems mandatory despite the use of high quality radiographs with optimal spatial resolution and contrast, and the value of supplementary special projections.  相似文献   
75.
端粒酶是一种RNA依赖的逆转录酶 ,能够延长染色体末端的端粒长度。它由三个主要部分组成———端粒酶RNA亚单位、端粒酶催化亚单位及连接二者的端粒酶相关蛋白。端粒酶激活是细胞永生化和肿瘤形成的关键步骤 ,其活性受到多种因素的调控。端粒酶催化亚单位hTERTmRNA可能是其激活的关键限速步骤。在妇科肿瘤的癌变过程中 ,端粒酶活性不同程度地升高 ,hTERT不断上调。端粒酶及其催化亚单位有可能成为妇科肿瘤筛查的一种重要的肿瘤标志物  相似文献   
76.
The experiments were performed on 34 dogs. The subcutaneous injection of boiled pancreatic juice was established to increase the survival of dogs in acute destructive pancreatitis (p < 0.001) and to decrease the specific volume damage to acinar (p < 0.01) and interstitial (p < 0.05) pancreatic tissue. It was also shown that boiled pancreatic autojuice exerted the therapeutic effect in chronic pancreatitis complicated by pancreatic fistulas. Five peptide components with a molecular mass from 4168 D to 1000 were discovered in the canine boiled pancreatic juice by liquid high pressure chromatography. Fractions with a molecular mass between 2187 and 1348 D were found to correspond to biologically active peptides, in particular to somatostatin. It is assumed that the therapeutic effect of boiled pancreatic juice used in acute pancreatitis may be due to somatostatin. Apparently pancreatic juice may turn an efficient therapeutic agent in acute pancreatitis and pancreatic fistulas.  相似文献   
77.
VEGF-C和VEGF-D蛋白表达在胰腺癌淋巴转移中的意义   总被引:1,自引:1,他引:0  
目的探讨胰腺癌中VEGF-C、VEGF-D蛋白表达与淋巴结转移之间的相关关系,阐明癌周淋巴管增生在胰腺癌淋巴转移中的作用及意义。方法免疫组化检测30例胰腺癌组织中VEGF-C、VEGF-D的表达及其与临床病理、淋巴结转移的关系。结果胰腺癌VEGF-C、VEGF-D蛋白表达阳性率分别为73%(22/30)、57%(17/30),肿瘤周边部位显著高于肿瘤中心部位,其表达与肿瘤的部位、分化程度、组织学类型无关,与肿瘤的TNM分期有关,Ⅲ~Ⅳ期显著高于Ⅰ~Ⅱ期。在VEGF-C、VEGF-D蛋白阳性组,淋巴结转移均显著增多。结论VEGF-C和VEGF-D与诱导胰腺癌淋巴管生成,促进肿瘤细胞淋巴道转移有关。  相似文献   
78.
情景模拟教学法在急诊教学中的应用   总被引:4,自引:0,他引:4  
薄惠云 《护理研究》2006,20(9):2436-2437
急诊是急、危、重病人集聚的医疗场所,涉及面广,且急诊病人就诊具有不确定性。而急诊教学工作要求在一定时间内完成教学计划,护生实习期间未必每个人都能遇上急诊病例,给急诊教学丁作带来困难。为此,于2002年9月-2004年11月对首都医科大学护理大专生临床实习实行情景模拟教学法,取得了较好效果。现介绍如下。  相似文献   
79.
颅底胆脂瘤的MRI特征   总被引:8,自引:0,他引:8  
目的探讨颅底胆脂瘤MRI分型的意义及其MRI诊断特征。方法观察15例颅底胆脂瘤的CT、MRI与病理学资料,根据肿瘤T1WI信号的不同,将颅底胆脂瘤分为Ⅰ型和Ⅱ型,分析两型胆脂瘤在CT、MRI征象和颅底骨质侵犯等方面的差异。结果15例颅底胆脂瘤T2WI显著高信号,肿瘤实质无强化。15例中,Ⅰ型,6例,肿瘤位于桥前池和桥小脑角区,CT均匀低密度,T1WI均匀低信号,包膜不强化,颅底骨质改变轻微,肿瘤实质为胆固醇结晶;Ⅱ型,9例,肿瘤位于一侧中、后颅窝底,CT呈混杂密度,T1WI呈混杂信号,其中4例为低信号中夹杂少量高信号,另5例以高信号为主,包膜强化,颅底骨质呈显著外压性改变,肿瘤实质为角化上皮和蛋白。结论颅底胆脂瘤分为Ⅰ型和Ⅱ型是合理的,体现了两型颅底胆脂瘤组织病理和生物学行为的差异,对指导MRI诊断有积极意义。T1WI信号多样性、T1WI显著高信号、肿瘤实质不强化以及与MRI分型相关的颅底骨质侵犯是颅底胆脂瘤的MRI诊断特征。  相似文献   
80.
把56只成年Wistar大鼠分为如下3组:①精索静脉曲张组(VG)30只;②精索静脉曲张人参二醇组皂甙组(VPG)8只;③假手术组(SOG)18只。实验结果表明,人参二醇组皂甙可显著提高精索静脉曲张大鼠睾丸ACE活力并降低睾丸LPO含量,但3组动物睾丸的SOD水平无明显差异。作者认为人参二醇组皂甙可能是通过减少LPO产生以提高ACE活力,从而实现对精索静脉曲张大鼠的保护作用。  相似文献   
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