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刘建波  卢丙伦  韩岩 《医学争鸣》1999,20(11):S103-S103
0 引言 拇指外伤后的急诊修复十分重要,以往各种方法各有其优缺点,我们介绍一种新的尝试.1 病例报告 患者男性,42岁,左拇指机器绞伤2h就诊.查体:全身情况好,左拇指近节中段以远皮肤软组织大部分撕脱,只有背部约1cm皮肤相连,但已受挤压,远端无充血...  相似文献   
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目的:血管内皮细胞生长因子(vascular endothelial growth factor,VEGF)在血管再生和骨组织再生过程中起着重要的调节作用。观察hVEGF165基因转染的骨髓间充质干细胞分泌VEGF的功能及转染后细胞的成骨活性。 方法:实验于2004—07/2005—12在江苏省血液研究所国家重点实验室完成。①体外分离、培养大鼠骨髓间充质干细胞,传代培养后以1μg PcDNA3.1-hVEGF165:3μL阳离子脂质体Lipofectamine的比例转染,通过免疫组织化学SP方法检测转染后细胞中外源性VEGF的表达。②体外分离、培养大鼠肾微血管内皮细胞,分别加入hVEGF165基因转染48h及1周后细胞上清、空载体转染及未转染组细胞上清,MTT法观察细胞增殖情况,以了解转染后细胞培养上清中VEGF的生物学活性。③测定在正常条件培养和成骨条件培养下,转染后细胞上清中碱性磷酸酶、骨钙素的水平。 结果:①hVEGF165基因转染的骨髓间充质干细胞能成功分泌VEGF蛋白。②hVEGF165基因转染48h组大鼠肾微血管内皮细胞A值高于空载体转染及未转染组(P〈0.05),但低于hVEGF165基因转染1周组。③成骨条件培养下,基因转染组细胞碱性磷酸酶和骨钙素的分泌量明显高于未转染组(P〈0.05);而在正常条件培养下,基因转染组细胞碱性磷酸酶和骨钙素的表达分泌量较低。 结论:①采用基因转染技术可将hVEGF165基因转染到骨髓间充质干细胞中并可有效表达具有生物活性的VEGF,且这种生物学活性呈剂量依赖性。②在成骨条件培养下,转染hVEGF165基因后骨髓间充质干细胞的成骨能力增强。  相似文献   
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Evatt  BL; Spivak  JL; Levin  J 《Blood》1976,48(4):547-558
The effects of administration of partially purified human urinary erythropoietin and rabbit thrombopoietin, and of endogenously produced erythropoietin and thrombopoietin on both red cell and platelet production were examined in mice. Partially purified thrombopoietin was prepared from rabbit plasma by sequential fractionation with ammonium sulfate precipitation, and DEAE and Sephadex G-100 chromatography. Preparations of thrombopoietin and partially purified human urinary erythropoietin (NIH No. H-11-TaLSL) were administered subcutaneously to normal mice, and the rate of incorporation of selenomethionine-75 Se into platelets was measured as an index of thrombopoietic activity of the infused material. Erythropoietin and thrombopoietin were assayed for erythropoietic activity by measuring the rate of appearance of 59Fe in the red cells of posthypoxic polycythemic mice. Preparations containing thrombopoietin had barely measurable erythropoietic activity, and 7 units of partially purified erythropoietin had little thrombopoietic activity. When endogenous levels of erythropoietin were increased by hypoxia, platelet production was not enhanced. Similarly, increased levels of thrombopoietin, induced in response to thrombocytopenia produced by platelet antiserum, did not alter red cell production. These data suggest that physiologically increased levels of thrombopoietin do not stimulate erythropoiesis, and that physiologically increased levels of erythropoietn do not stimulate thrombopoiesis. However, currently available, partially purified preparations of erythropoietin and thrombopoietin may be capable of stimulating both platelet and red cell production if used in sufficient quantities.  相似文献   
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Data from 1158 cases of septic arthritis reported to the Public Health Laboratory Service (PHLS) Communicable Disease Control Centre (CDSC) from England and Wales over a 4 yr period (January 1990 December 1993) are presented. Reports where a bacterial organism was isolated from synovial fluid, or where an organism was isolated from blood cultures where a diagnosis of septic arthritis was reported, were examined. Reports of infection were more common in children (12.7% of infections were in the under 10 age group) and the elderly (54.7% aged 60 or over), and were higher in males in all age groups except in the elderly. The most common causative organisms remain staphylococcal and streptococcal species, comprising 40.6% (470) and 28% (324) of cases, respectively. The most common streptococci seen were Streptococcus pneumoniae and Lancefield group A beta-haemolytic Streptococcus organisms, 60.8% (197/324), although group B, C and G organisms accounted for 33.6% of streptococcal isolates (109/324). Haemophilus influenzae septic arthritis is not exclusive to children as 23.2% (16- 69) of cases occurred over the age of 15. A total of 48% (635) of isolates were identified from both synovial fluid and blood cultures, 32.6% (378) from joint fluid alone and 12.5% (146) from blood cultures. Although this study excludes cases of septic arthritis where no organism was isolated, it presents important bacteriological information from a large number of isolates from England and Wales over a 4 yr period. Risk factors identified include a joint prosthesis, joint disease/connective tissue disorder. immunosuppression and diabetes.   相似文献   
80.
Lairmore  MD; Jason  JM; Hartley  TM; Khabbaz  RF; De  B; Evatt  BL 《Blood》1989,74(7):2596-2599
Concern for transmission of human T-cell lymphotropic virus, type 1 (HTLV-1) infection to recipients of infected cellular blood products has prompted development of tests to eliminate blood units with HTLV-I antibodies. Most hemophilic men from the United States became infected with human immunodeficiency virus (HIV) before HIV donor screening and before blood products were processed to inactivate the virus. To assess whether these men might also be infected with HTLV-I, we examined the HTLV-I antibody status of 127 factor VIII (hemophilia A) recipients and 71 factor IX (hemophilia B) recipients. One HIV-seronegative and four HIV-seropositive persons were HTLV-I reactive by enzyme-linked immunosorbent assay (ELISA). Four of five ELISA-reactive serum samples were negative by HTLV-I immunoblot assay (IB); 1 reactive and 1 borderline reactive serum were indeterminate on IB (p19 reactivity), but negative by radioimmunoprecipitation assay (RIPA). Peripheral blood mononuclear cells from one patient with indeterminate HTLV-I IB were negative for HTLV-I genomic sequences by polymerase chain reaction. The other indeterminate patient's serum antibody pattern was stable over a 2-year period, suggesting this was not an instance of early HTLV-I seroconversion. These results reaffirm the safety of factor components in the United States with regard to HTLV-I but emphasize the importance and need for further testing of reactive HTLV-I ELISA results with a second more specific technique.  相似文献   
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