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101.
102.
Bone marrow transplantation (BMT) is often followed by significant morbidity and mortality due to protracted immunodeficiency. We have hypothesized that the bone marrow-ablative regimen may delay the recovery of normal immune function following transplantation by impairing the interaction of host endothelial cells with circulating graft-derived lymphocytes. This report compares the relative effects of busulfan (an alkylating drug) and gamma-irradiation on the tissue- specific localization potential of lymphocytes and the eventual recovery of immune function within syngeneic murine transplant recipients. Localization of normal lymphocytes into peripheral lymph nodes of irradiated BMT recipients was markedly less (less than 50%) than in busulfan-treated or normal mice over the first 2 months post- BMT. This finding correlated with irradiation-induced endothelial cell edema and microvascular occlusions within lymphocyte-receptive areas of the nodal microvasculature. The effect of both preparative regimens on the recovery of contact hypersensitivity (CHS) was also analyzed. This response recovered more quickly (between 1 and 2 months) in busulfan- pretreated animals. Further experiments demonstrated that the decrease in CHS responsiveness appeared, in part, related to a depression in the capacity of lymphocytes to localize into skin sites of antigen deposition within irradiated mice. The impairment of tissue-specific lymphocyte localization may represent a novel mechanism by which whole body irradiation can contribute to delayed immunologic reconstitution following bone marrow transplantation. 相似文献
103.
石南藤、山蒟活性成分的分离和结构鉴定 总被引:4,自引:0,他引:4
已报道自山蒟及石南藤中分得海风藤酮(Ⅰ),denudatin B(Ⅱ),N-isobutyl-deca-trans-2-trans-4-dienamide(Ⅲ),本文继续报道自山蒟中分得一新木脂素,命名为山蒟素D(Ⅳ),X-衍射晶体结构测定为外消旋光学异构体。自石南藤分得Ⅳ的同系物,为新结构、命名为南藤素(Ⅴ),以及山蒟素C(Ⅵ),galgravin(Ⅶ),二氢毕拨明宁碱(Ⅷ)及巴豆环氧素(Ⅸ)。以上化合物皆首次自山蒟及石南藤中分得。以血小板活化因子(PAF)引起的血小板凝集实验测定活性,除Ⅲ,Ⅳ,Ⅶ,Ⅸ外皆有抑制活性。 相似文献
104.
Increased detection of hepatitis C virus infection in commercial plasma donors by a third-generation screening assay 总被引:4,自引:0,他引:4
SR Lee ; CL Wood ; MJ Lane ; B Francis ; C Gust ; CM Higgs ; MJ Nelles ; A Polito ; R DiNello ; D Achord 《Transfusion》1995,35(10):845-849
BACKGROUND: Routine screening of blood donations with second-generation hepatitis hepatitis C virus (HCV) assays has substantially reduced the occurrence of posttransfusion hepatitis. However, following the development of third-generation assays, several studies indicated that these assays may identify HCV-infected individuals who are not identified by second-generation assays. STUDY DESIGN AND METHODS: The sensitivity of a third-generation HCV enzyme-linked immunosorbent assay (ELISA-3) was compared with a second-generation ELISA (ELISA-2) in a side-by-side study of 9936 commercial blood donors. ELISA-reactive specimens were subjected to supplemental analysis by third-generation recombinant immunoblot assay and polymerase chain reaction. RESULTS: ELISA-3 demonstrated greater sensitivity than ELISA-2, detecting 1 additional recombinant immunoblot assay-positive specimen per 2000 tested. ELISA-3 also detected 1 additional HCV-infectious polymerase chain reaction-positive unit among approximately 10,000 units screened. CONCLUSION: The incremental sensitivity achieved with ELISA-3 can be expected to eliminate approximately 20 infectious donations per week among those made by commercial donors in the United States. In accordance with previous studies, most of the improved sensitivity of ELISA-3 derives from its increased detection of anti-c33c (NS3), rather than from the inclusion of HCV antigen NS5. 相似文献
105.
用多次注射吗啡的方法造成大鼠对吗啡的依赖,给大鼠脊髓蛛网下腔(i.t.)注射k(kappa)阿片受体激动剂U-50,488H(2.5、5、10μl)或k受体拮抗剂nor—BNI(1.25、2.5、5μl/10μl)后,用纳洛酮(NX)催瘾,观察并记录四种戒断症状:湿科(wetshakes)、咬牙(teethchattering)、逃跑企图(escapeattempts)、体重丢失(weightlose)。结果表明U—50,488H可以明显减轻湿抖、咬牙和逃跑企图,并呈量效关系;nor—BNI则使温抖、咬牙和体重丢失三种症状明显加重,也呈量效关系。上述结果表明,激活脊髓。受体对吗啡戒断症状有明显的抑制作用,阻断K受体则加重戒断症状。 相似文献
106.
头孢噻肟在实验性糖尿病鼠的药代动力学和药效学研究 总被引:4,自引:0,他引:4
用四氧嘧啶(alloxan)引起的大鼠糖尿病模型,观察糖尿病早期对头孢噻肟(CTX)药代动力学和药效学的影响。HPLC方法测定CTX的血药浓度,用计算机计算各项药代参数。糖尿病组动物的血药峰浓度和AUC值明显低于对照组,但两组的T1/2ka和T<>/i>1/2ke无明显差别,提示糖尿病早期不影响CTX的吸收和消除速度。但由于CTX的蛋白结合率降低,游离药物浓度增加,大量游离药物进入组织液,可使血中药物总浓度降低。CTX对两组动物肺炎球菌感染的PD50无明显差别,可能与糖尿病大鼠血中游离的药浓度提高有关。 相似文献
107.
TA Griffin RW Hostoffer K-Y Tserng DJ Lebovitz CL Hoppel JL Mosser D Kaplan DS Kerr 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(7):875-878
The mechanisms of hypocalcemia, recurrent infections and hypogammaglobulinemia associated with metabolic decompensation of propionic acidemia due to propionyl-CoA carboxylase deficiency have not been defined. A 7-week-old infant with this disorder presented with severe hypocalcemia and B cell lymphopenia during an episode of metabolic acidosis and hyperammonemia. Hypocalcemia (1.1 mmoll 1 ) was associated with elevated serum intact parathyroid hormone (122 ng 1 1 ), hyperphosphatemia, hypophosphaturia and hypercalcuria, indicating parathyroid hormone resistance. B cell lymphopenia (20 cells μl-1 ) was associated with transient neutropenia, anemia and subsequent hypogammaglobulinemia (IgG < 294mgdl-1 , IgM < 8mgdl-1 , IgA < 8mgdl 1 ), while T cells were normal. Parathyroid hormone resistance and B cell lymphopenia resolved following treatment with hemodialysis, diet and carnitine. These complications may be due to interference with parathyroid hormone renal tubular action and B cell maturation/proliferation by accumulated organic acids. 相似文献
108.
氟康唑治疗复发性真菌性阴道炎32例 总被引:1,自引:0,他引:1
0 引言 真菌性阴道炎是妇科常见病 ,常因治疗不彻底 ,反复发作而转为慢性 .2 a来我们采用氟康唑治疗复发性真菌性阴道炎 32例 ,取得较好疗效 .1 对象和方法1.1 对象 本组 32例 ,年龄 18~ 6 2 (平均 33岁 ) .未婚 2例 .已婚 30例 ,病程 0 .5~ 8a,平均 10 mo.诊断 :1明显自觉症状 :外阴、阴道瘙痒、烧灼感 ,皮肤粘膜充血 ,白带增多、豆渣样 .2阴道分泌物涂片 :显微镜下找到菌丝及芽孢 .3反复发作 :1a内有 4次复发症状出现 ,除外其他病变 [1 ,2 ] .1.2 方法 氟康唑由第二军医大学药学院提供 ,15 0 mg顿服 ,2~ 3wk1次 .治疗期间停用与… 相似文献
109.
110.
OBJECTIVE: To develop national charts of birthweight percentiles by gestational age and infant sex for liveborn twins born in Australia. METHODOLOGY: National data on live twin births to non-Indigenous Australian-born mothers during 1991-94 were derived from perinatal data collected by midwives in each State and Territory. RESULTS: During 1991-4 there were 20,075 liveborn twin infants. Of these births, missing data included: birthweight 36 (0.2%) births, gestational age 95 (0.5%) births, and sex (missing or indeterminate) 13 (0.06%) births. These births were excluded from the study. An additional 0.6% births were excluded because the recorded birthweights were extreme outliers for the recorded gestational ages. Forty-seven per cent of live twin births were preterm (< 37 weeks). At all gestational ages, the median birthweight of male twins was higher than that of female twins. At model gestational age of 38 weeks, the difference in the median birthweight was 130 g. CONCLUSIONS: The charts produced as a result of the study provide birthweight percentiles by gestational age for twins based on national data in Australia. They provide current population norms for the use of Australian clinicians and researchers. 相似文献