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71.
基于网络的医学信息资源分布及检索策略   总被引:1,自引:0,他引:1  
因特网的医学信息资源包括电子期刊、图书信息、报纸、学位论文等。可以进入数据库、网站直接检索,或利用搜索引擎及专业信息资源导航系统获取信息资源。  相似文献   
72.
脂肪干细胞免疫学性状的初步实验观察   总被引:3,自引:0,他引:3  
目的初步研究脂肪干细胞(Adiposederivedstemcells,ADSC)表面免疫分子的表达以及体外免疫调节功能,以期为组织工程提供同种异体种子细胞来源。方法体外培养人脂肪抽吸术中获取的脂肪干细胞,体外培养至第二代,流式细胞仪检测免疫分子HLA、HLA、B7-1、B7-2、CD40的表达。1×105个/孔ADSC细胞分别刺激单一异体淋巴细胞或混合双向淋巴细胞反应,观察淋巴细胞增殖情况。同时观察ADSC经IFN-γ作用后,免疫分子表达与淋巴细胞增殖的调节情况。结果ADSC表达HLA类分子,但未检测到HLA类分子阳性表达。B7-1(CD80)、B7-2(CD86)、CD28、CD40未见明显阳性表达。人IFN-γ刺激48h后,HLA类分子表达明显增高,HLAI表达未见明显增高。异体或经IFN-γ作用的ADSC均未能刺激异体淋巴细胞增殖。同样数量的ADSC可明显抑制双相混合淋巴细胞增殖,经IFN-γ作用后抑制作用未见明显减弱。结论ADSC具有一定的体外调节淋巴细胞反应的能力,有可能成为组织工程同种异体细胞来源。  相似文献   
73.
Summary Sixteen patients with symptoms typical for Ockelbo disease (rash, arthralgia, fever) were enrolled in a 2 1/2 year study, during which clinical symptoms were recorded and ELISA was employed to study specific IgM, IgG and IgG subclass development. Initially, all patients presented with rash and arthralgia, and five patients still suffered from joint symptoms at the end of the study period. Ockelbo virus specific IgM was detected during the first week post onset in 6 patients and in 15 patients by day 14. One patient failed to develop specific IgM and was later diagnosed with a human parvovirus B 19 infection. All patients were IgM-negative 2 1/2 years post onset. Seroconversions or significant titer rises for specific total IgG were seen in 15 patients. IgG titers generally peaked within one year but in two patients maximum titers were seen 2 1/2 years post onset. Development of IgG1 followed that of total IgG, while IgG3, after an initial increase in all Ockelbo disease patients, remained at peak levels for one year in four patients, three of whom still had detectable IgG3 at the end of the study period. Ockelbo virus specific IgG2 or IgG4 was not detected in any of the patients.  相似文献   
74.
国产氟康唑对小鼠隐球菌病的疗效   总被引:1,自引:1,他引:0  
以5×103cfu/鼠的新型隐球菌给小鼠脑室感染(ic)1h后,分别口服氟康唑(Flu)5和10mg/(kg·d)或酮康唑(Ket)50和100mg/(kg·d),bid×9d。对ic小鼠连续观察40天的存活率和平均存活时间,Ful分别为50%~70%和8~15天,Ket是30%~40%和5~9天。由小鼠侧尾静脉注射106cfu/鼠新型隐球菌3天后产生的全身感染,分别给小鼠口服Flu2.5~10mg/(kg·d)或Ket25~100mg/(kg·d),bid×9d。感染24、28和32天的PD50Flu是2.7、3.5和6.7mg/kg,Ket为28.4、70.4和83mg/kg;Flu和Ket的平均存活时间分别是23~34天和20~31天。在上述两种实验模型中分离脑和肺做细菌培养,Flu均与对照和50mg/(kg·d)的Ket比较,对ic10天及静脉注射感染13天的小鼠,口服5和10mg/(kg·d)或2.5~10mg/(kg·d)Flu均显著抑制新型隐球菌生长。  相似文献   
75.
The results of a modified Wilson shaft osteotomy for hallux valgus in 77 feet of 51 patients were excellent or good in 62 feet after 2 to 4 years. The correction of the hallux valgus angle and intermetatarsal angle was excellent or good in 69 feet. The operation is technically simple provided dorsal angulation of the distal fragment is avoided in the early postoperative period.A  相似文献   
76.
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   
77.
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   
78.
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   
79.
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   
80.
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   
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