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81.
利用木瓜蛋白酶分别制备了抗汉坦病毒鼠源性单克隆抗体(mAb)3G1和3D8F(ab′)2片段。通过WaterDEAE40HR阴离子交换色谱柱纯化后,非还原型SDSPAGE呈现单一条带,相对分子质量(Mr)约100000。两种F(ab′)2片段均具有良好的血凝抑制活性、病毒中和活性及对汉坦病毒感染乳鼠的保护作用  相似文献   
82.
DICOM医学图像的存储与管理   总被引:11,自引:0,他引:11  
随着数字化医学成像设备在医院的广泛使用,对医学图像及相关数据的存档管理以及在不同科室之间的数据共享的要求越来越迫切,这就需要建立PACS(图像存档和通讯系统),这方面国外已经发展了很多年,我国目前处于起步阶段.本文参照PACS系统的一个已经被国际认可的医学图像标准即医学成像和通讯标准DICOM(digital imaging and communication in medicine),研究了标准的各个部分,特别是兼容性、信息对象定义(IOD)、服务对象对类(SOP)、数据编码等部分,就具体实现PACS系统的一个重要方面即医学图像的存档和管理做了深入的探讨,在此基础上建立了医学图像数据库系统,为实现医学图像信息的网络共享打下了基础.  相似文献   
83.
The feasibility of the major peripheral blood leukocyte (PBL) subsets for use in qualitative and quantitative PCR to monitor secondary cytomegalovirus (CMV) infection and ganciclovir therapy was assessed with 188 blood samples derived from 40 CMV immunoglobulin G-positive renal-allograft recipients. In pp65 antigen-positive patients all leukocyte fractions, but only 79.5% of plasma preparations, were PCR positive. In pp65 antigen-negative samples from patients after antiviral treatment only 7.3% of polymorphonuclear cell (PMNL) samples, but 81.8% of peripheral blood mononuclear cells (PBMC), and 10.9% of plasma samples remained PCR positive. Similarly, in patients with latent infections only 5.0% of PMNL, but 51.7% of PBMC preparations, and 8.0% of plasma samples were PCR positive. Regarding patients with active CMV infection, CMV DNA copy numbers in PMNL correlated significantly with pp65 antigen-positive cell counts before and after onset of ganciclovir therapy. Significant differences in CMV DNA copy numbers in PMNL and plasma were observed (i) between patients with symptomatic infection and those with asymptomatic infection and (ii) between patients with active infection and those with latent infection. In contrast, PBMC harbored equally low CMV DNA levels both in patients with active infection and those with latent infections, and no decline of CMV DNA load in PBMC was observed during antiviral treatment. We conclude that detection of CMV DNA in PMNL, not in PBMC, is associated with active infections and is more sensitive than detection of CMV DNA in plasma. Negative PCR results for PMNL after antiviral therapy indicate recovery, and fewer unwanted positive results occur compared to PBMC and plasma. Therefore, purified PMNL should be preferred for analysis by qualitative CMV PCR to avoid unwanted positive results. The CMV DNA load in PBMC compared with that in PMNL is negligible during active infection, so mixed PBL are sufficient for use in quantitative PCR.  相似文献   
84.
Five cases of non-molar trophoblastic disease including one placental site trophoblastic tumor (PSTT), two exaggerated placental sites and two choriocarcinomas were compared with each other and with normal chorionic villi and placental site. This involved light microscopic, immunohistochemical and ultrastructural studies. Comparison of PSTT with choriocarcinoma suggested that the former represented a neoplastic transformation of placental site intermediate trophoblast. The PSTT showed a characteristic immunohistochemical distribution of human placental lactogen and human chorionic gonadotropin, resembling that of the placental site intermediate trophoblast. Placental site trophoblastic tumor cells were also characterized ultrastructurally by prominent perinuclear filaments, abundant rough endoplasmic reticulum, or both. Infiltrating intermediate trophoblasts in exaggerated placental sites were similar to PSTT cells rather than normal placental site intermediate trophoblasts. However cells with vacuolated cytoplasm or spindle-shaped intermediate trophoblastic ceils were observed more frequently in the PSTT than the exaggerated placental sites. The intermediate trophoblastic cells in the choriocarcinomas showed a morphologically transitional form from cytotrophoblastic cell to syncytiotrophoblastic cell, but did not share unique ultra-structural similarities with placental site intermediate trophoblasts.  相似文献   
85.
TLR4 gene variants modify endotoxin effects on asthma   总被引:6,自引:0,他引:6  
BACKGROUND: Environmental exposure to endotoxin might have a crucial role in immune maturation and development of asthma. OBJECTIVE: The aim of this study was to investigate whether the effect of endotoxin concentration in settled house dust on asthma is modified by the presence of variation in the TLR4 gene. METHODS: We performed a cross-sectional study within the German follow-up of the European Community Respiratory Health Survey. Multivariate logistic regression analysis and nonparametric effect estimates (S-Plus) were applied to examine the association between endotoxin exposure and diagnosed asthma, related clinical symptoms, and bronchial hyperreactivity (BHR) stratified for noncarriers and carriers of G299/I399 polymorphism in the TLR4 gene. RESULTS: In the noncarrier group (n = 279), the prevalence of asthma was significantly increased with elevated endotoxin levels in house dust with adjusted odds ratio 6.24 (95% CI, 1.33-29.17) in the second tertile, and 4.54 (95% CI, 0.94-21.96) in the third tertile compared with the lowest endotoxin tertile. The carriers of the polymorphisms (n = 55) showed a nonsignificant trend to have a lower risk of asthma (crude odds ratio, 0.67; 95% CI, 0.06-8.06 for the second tertile and 1.33; 95% CI, 0.17-10.58 for the third tertile). We found a similar association for wheeze and endotoxin exposure that was also attenuated in subjects with G299/I399 polymorphisms. CONCLUSIONS: The G299/I399 polymorphisms were associated with a modified response to endotoxin, but the functional relationship still needs clarification.  相似文献   
86.
G-CSF对外周血树突状细胞亚群比例的影响   总被引:1,自引:2,他引:1  
目的 :了解G CSF对小鼠外周血树突状细胞 (DC)亚群比例的影响。方法 :以不同剂量 (0、5 .0、10 .0或 15 .0 μg)的G CSF ,分别皮下注射于BALB/c小鼠 ,连续 6d ,每天 1次。第 6天分离外周血DC ,用流式细胞仪检测DC1(CD11c+ CD8a-)和DC2 (CD11c+ CD8a+ )的比例并计算其绝对值。结果 :经不同剂量的G CSF刺激后 ,外周血DC1的绝对值无显著变化 ,而DC2的绝对值增加 5倍 (9.6× 10 6/Lvs 5 5 .1× 10 6/L ,P <0 .0 1) ,DC1/DC2比值降低 (4.2vs 0 .7,P <0 .0 1)。结论 :G CSF在体内可提高外周血DC2的绝对数 ,对DC1的数无明显影响 ,从而使DC1/DC2的比例倒置  相似文献   
87.
The early experience is reported here of the use of Intra-operative frozen-section service by telepathology using the Integrated Service Digital Network (ISDN), a commercially available system that is being connected between the Department of Pathology of Tottori University and Matsue City Hospital, a distance of 30 km. The transfer rate is currently 64kbit/s. The frozen-section service was conducted for a total of 117 tissue specimens (organs) from 100 patients between August 1993 and May 1995. The average time taken for examination of each specimen of frozen section was 13min, ranging between 2 and 42min. The average number of transmitted Images was 6.2. Six cases necessitated more than 11 transmitted Images to make a diagnosis, while 13 cases could be diagnosed from two images only. Correct and permissible diagnoses were obtained in 109 (93.2%) out of 117 specimens when comparing the telepathology diagnosis with that of direct microscopy. Improper or misdiag-nosis was made for eight cases (specimens), which were misinterpreted as papillary carcinoma in Basedow's disease, adenoma and hyperplasia in two pheochromocytomas, solid-tubular carcinoma in phyilodes tumor, mastopathy in invasive carcinoma, metastatic carcinoma in astrocytoma, follicular lymphoma in reactive hyperplasia, and lymphadenitis in follicular lymphoma. in retrospect, diagnosis of these cases should have been deferred. From the results, it was concluded that the Intraoperatlve frozen-section service by telepathology may be a worthwhile substitute for hospitals with limited accessibility to local pathology service, in spite of pitfalls in some cases. Well prepared, high-quality frozen sections, sufficient verbal communication with surgeons, and a rather conservative attitude on the part of a well-trained pathologist seem to be the essential Ingredients for reaching an accurate decision when using telepathology.  相似文献   
88.
干扰素诱导淋巴瘤细胞凋亡实验及临床研究   总被引:2,自引:0,他引:2  
目的:分析梯度浓度的干扰素(IFN-α)对Burkitt淋巴瘤细胞株Daudi和T细胞淋巴瘤细胞株Jurkut及15例难治性淋巴瘤患者的直接作用。方法:以MTT法测定梯度浓度的IFN-α对两种淋巴瘤细胞株Daudi、Jurkat增殖作用的影响,以DNA末端标记法,流式细胞术,电镜观察测定IFN-α对淋巴瘤细胞的凋亡诱导作用,并采用瘤内注射IFN-α联合化疗治疗15例耐药的难治性淋巴瘤。结果:低浓度亚IFN-α对DaudiJurkat细胞增殖无明显抑制作用,高浓度IFN(10000U/ml)可显著抑制两种细胞增殖,且有时间相关性。高浓度的IFN-α可诱导淋巴瘤细胞凋亡。15例患者CR5例,PR7例,有效率80%,无明显毒副作用。结论:IFN-α可抑制淋巴瘤细胞增殖,诱导凋亡,有显著时间,剂量依赖性。局部应用IFN-α联合化疗是治疗难治性淋巴瘤的有效方法之一。  相似文献   
89.
目的 探讨慢性乙型肝炎(CHB)患者血清维生素E水平与肝组织病理的关系.方法 选择66例慢性乙型肝炎患者进行肝穿刺病理学检查,健康对照组10例.化学比色法检测血清维生素E表达水平,同时检测HBV DNA、HBeAg及肝功能.结果 与正常对照组相比,慢性乙型肝炎患者血清维生素E水平明显降低(P<0.01);HBeAg阳性组与HBeAg阴性组比较,血清维生素E水平无明显差别(P0.05).CHB患者血清维牛素E水平与肝脏组织炎症呈负相关关系(r=-0.451,P<0.05),而与肝脏组织纤维化程度无明显相关(r=0.02,P0.05).结论 维生素E作为体内重要的抗氧化剂,参与了慢性乙型肝炎的炎症过程.在肝脏炎症过程中,适当补充维生素E,可能有助于缓解病情.  相似文献   
90.
Effect of azelastine on the release and action of leukotriene C4 and D4   总被引:1,自引:0,他引:1  
The effect of azelastine on the release of leukotriene C4 and D4 (LTC4 and LTD4), and the antagonistic action of the drug against the leukotrienes were determined by using in vitro tests and compared with those of ketotifen and chlorpheniramine. Azelastine inhibited LTC4 and LTD4 release from guinea pig lung fragments passively sensitized with homologous anti-ovalbumin IgGl-b antibody. The 50% inhibitory concentration (IC50) of azelastine was 6.4 X 10(-5) M for a 15-min preincubation or 4.7 X 10(-5) M for a 30-min preincubation. Ketotifen and chlorpheniramine were inhibitory only at the highest concentration tested (3 X 10(-4) M), giving inhibitions of 35.6 and 21.3%, respectively. Azelastine also inhibited calcium ionophore A23187-induced release of leukotrienes from human polymorphonuclear leukocytes; the IC50 values were 3.6 X 10(-5) M for 15 min and 2.3 X 10(-6) M for 30 min of preincubation. Ketotifen and chlorpheniramine were inhibitory only after a 30-min preincubation, with IC50 values of 2.1 X 10(-5) and 5.9 X 10(-5) M, respectively. The potent inhibition by azelastine might be partly a result of the inhibition of 5-lipoxygenase, since 5-hydroxyeicosatetraenoic acid formation in rat basophilic leukemia cell homogenate was inhibited by azelastine. Pretreatment of guinea pig ileum with azelastine antagonized LTC4- and LTD4-induced contraction of the ileum with IC50 values of 7.0 X 10(-6) and 1.1 X 10(-5) M, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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