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31.
目的建立泰泽氏病原体(Ty)纯化方法,获得纯的菌体供抗原研究,为ELISA诊断抗原的制备提供依据;并尝试建立Ty隐性感染血清学抗原检查方法。方法选择特异性抗体包被磁珠,从感染大鼠肝脏中富集和纯化Ty;用SDS-PAGE和Western blot技术考察纯化Ty的蛋白和抗原图谱;同时用免疫磁珠分离技术(IMS)直接检查隐性感染大鼠肠道上皮细胞内的Ty。结果用辛酸-硫酸铵纯化的Ty单克隆抗体M5以0·5μg/107beads以上浓度包被抗IgG抗体预结合的磁珠4h,可最大效率地富集Ty;分离反应进行1h,敏感性达到103菌体/mL;吖啶黄染色镜检法可以直接、快速地观察到结合于磁珠上的细菌;抗原分析表明,IMS较好地去除了肝组织和真核细胞成分,纯化的Ty RJ株具有3个免疫优势的抗原成分,相对分子质量(Mr)分别为160×103、116×103、55×103;此外,IMS法可直接从隐性感染大鼠盲肠上皮细胞中检测到少量寄生的Ty。结论用IMS技术可有效地富集和纯化Ty,并可以作为Ty隐性感染血清学抗原检查的候选方法。 相似文献
32.
Body weight and comorbidity predict mortality in COPD patients treated with oxygen therapy. 总被引:1,自引:0,他引:1
The aim of this study was to investigate the association between clinical variables and all-cause and respiratory mortality in patients with chronic obstructive pulmonary disease (COPD) undergoing long-term oxygen therapy (LTOT). The authors retrospectively studied a historic cohort of 128 patients with COPD (126 males, mean age+/-SD 68.9+/-9.7 yrs, body mass index (BMI) 25.1+/-4.5 kg.m-2, and forced expiratory volume in one second 25.4+/-8.8% predicted), who were being treated with long-term oxygen therapy in a tertiary teaching hospital between 1992 and 1999. Comorbidity, assessed with the Charlson Index, was present in 38% of the patients. Vital status and cause of death were assessed through the population death registry. A total of 78 patients (61%) had died by the end of follow-up. Three-year survival was 55%. Death was due to respiratory causes in 77% of cases. On Cox analysis, BMI<25 kg.m-2, comorbid conditions, age>or=70 yrs and cor pulmonale were associated with all-cause mortality. The BMI and comorbidity were the only significant predictive factors when the analysis was restricted to respiratory mortality. In conclusion, body mass index<25 kg.m-2 and comorbidity were predictors of all-cause and respiratory mortality in a cohort of chronic obstructive pulmonary disease patients treated with long-term oxygen therapy. These factors should be taken into account when considering the management and prognosis of these patients. 相似文献
33.
不同病理类型原发性甲状旁腺功能亢进症临床表现的比较分析 总被引:2,自引:0,他引:2
目的 分析不同病理类型甲状旁腺功能亢进(PHPT)的临床表现特点。方法 回顾性分析1958-2005年北京协和医院收治经手术病理证实的280例PHPT患者的临床资料。按病理类型分为甲状旁腺腺瘤组208例,甲状旁腺增生组52例及甲状旁腺腺癌组20例。结果 腺癌组中男性高于另外2组(P〈0.05)。增生及腺癌组中骨畸形、骨软化比例较低,增生组骨吸收、病理性骨折比例低于腺瘤组;胃肠道症状、多饮多尿及泌尿系统病变在腺癌组中高于另外2组(P均〈0.05)。血总钙(TCa)、血游离钙离子(ICa)及24h尿Ca在腺癌组显著高于腺瘤组及增生组(P均〈0.01),在腺瘤组与增生组间差异无统计学意义(P〉0.05)。出现高钙危象的比例在腺癌组显著高于另外2组(P〈0.01)。腺癌组病灶重量高于增生组,腺瘤组病灶直径小于增生组(P均〈0.05)。结论 在本组病例中,腺癌组男性比例较高,泌尿系统病变更为多见,出现高钙危象的比例显著增高,术后复发的比例较高。增生组骨骼系统病变相对较轻,其病变甲状旁腺重量低于腺癌与腺瘤组。 相似文献
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36.
A. HAZIOT I. KATZ G. W. RONG X. Y. LIN J. SILVER & S. M. GOYERT 《Scandinavian journal of immunology》1997,46(3):242-245
Membrane-bound CD14 acts as a receptor for lipopolysaccharide (LPS) on monocytes/macrophages and neutrophils. Studies have suggested that the activation of monocytes/macrophages by the binding of LPS to membrane-bound CD14 may require the association of a signal-transducing molecule with membrane-bound CD14. The observation that non-CD14 expressing cells, such as endothelial cells, can nevertheless be activated by a complex of LPS and a soluble form of CD14 (sCD14) suggests that the receptor for this complex may be identical to the signal transducing molecule associated with membrane-bound CD14. The studies described show that two CD14-specific MoAb are able to block the LPS-induced activation of endothelial cells but do not affect the response of monocytes to LPS. This suggests that the interaction of the sCD14:LPS complex with endothelial cells is distinct from the interaction of membrane-bound CD14 with its putative signal-transducing molecule. 相似文献
37.
Plasmid DNA encoding transforming growth factor-beta1 suppresses chronic disease in a streptococcal cell wall-induced arthritis model. 总被引:6,自引:0,他引:6
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X Y Song M Gu W W Jin D M Klinman S M Wahl 《The Journal of clinical investigation》1998,101(12):2615-2621
Transforming growth factor beta is a potent immunomodulator with both pro- and antiinflammatory activities. Based on its immunosuppressive actions, exogenous TGF-beta has been shown to inhibit autoimmune and chronic inflammatory diseases. To further explore the potential therapeutic role of TGF-beta, we administered a plasmid DNA encoding human TGF-beta1 intramuscularly to rats with streptococcal cell wall-induced arthritis. A single dose of 300 microg plasmid DNA encoding TGF-beta1, but not vector DNA, administered at the peak of the acute phase profoundly suppressed the subsequent evolution of chronic erosive disease typified by disabling joint swelling and deformity (articular index = 8.17+/-0. 17 vs. 1.25+/-0.76, n = 6, day 26, P < 0.01). Moreover, delivery of the TGF-beta1 DNA even as the chronic phase commenced virtually eliminated subsequent inflammation and arthritis. Both radiologic and histopathologic as well as molecular evidence supported the marked inhibitory effect of TGF-beta1 DNA on synovial pathology, with decreases in the inflammatory cell infiltration, pannus formation, cartilage and bone destruction, and the expression of proinflammatory cytokines that characterize this model. Increases in TGF-beta1 protein were detected in the circulation of TGF-beta1 DNA-treated animals, consistent with the observed therapeutic effects being TGF-beta1 dependent. These observations provide the first evidence that gene transfer of plasmid DNA encoding TGF-beta1 provides a mechanism to deliver this potent cytokine that effectively suppresses ongoing inflammatory pathology in arthritis. 相似文献
38.
糖耐量试验对评价肝癌患者肝脏储备功能的价值 总被引:5,自引:0,他引:5
绝大多数肝细胞性肝癌患者合并肝硬变,为预测其对肝切除的耐受性,给正确选择切肝患者提供依据,作者对62例切肝者和49例未切肝者手术前后的糖耐量试验(OGTT)和肝组织病理学进行了对比研究。结果:术前OGTT曲地P型者切肝后恢复顺利;L型者对肝切的耐受性差,术后易发生肝功能衰竭等并发症,其肝硬化和蔼多为CⅢ或CⅣ级,曲线形态界于P和L型之间的I型患者29例用肝门区域血管阻断法切肝,并在阻断血管前使用预 相似文献
39.
L-丙酰肉碱对再灌注心肌损伤的保护及体外抗自由基作用 总被引:1,自引:0,他引:1
目的:观察L-丙酰肉碱对缺血再灌注心肌的保护作用,并探讨其机理。方法:采用大鼠在体心脏冠状动脉前降支阻断5min造成缺血再灌注模型,持续心电监护,观察心律失常与心功能指标;应用电子顺磁共振观察L-丙酰肉碱对Fenton体系及二甲基亚砜(DMSO)碱性有氧体系产生自由基的作用。结果:L-丙酰肉碱静脉给药明显减少再灌注时室性心动过速、室性纤维颤动的发生(P<0.05),促进再灌注后左室收缩压、左室压最大上升速率、左室压最大下降速率、心力环面积的恢复,与对照组相比,各参数均明显增高(P<0.05);静脉注射L-丙酰肉碱100mmol/L时促进Fenton体系OH的产生,而500mmol/L时产生明显抑制作用,L-丙酰肉碱明显抑制DMSO碱性有氧体系OS的产生。结论:L-丙酰肉碱明显减少再灌注心律失常的发生,促进再灌注后心功能的恢复。推测它对自由基的作用可能是再灌注损伤保护机理之一。 相似文献
40.
V. S. Akhunov T. V. Mirenburg X. D. Krasnopolskaya 《Journal of inherited metabolic disease》1994,17(1):104-111
Summary GM1- and GM2-gangliosides were isolated from brain and radio-labelled. The labelled moieties were localized by hydrolysis with lysosomal enzymes, followed by thin-layer chromatography of the products. High-resolution loading tests with labelled gangliosides were developed and found to differentiate infantile and juvenile forms of GM1- and GM2-gangliosidoses as well as the identification of B, O and AB types of GM2-gangliosidosis. 相似文献