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91.
Recent reports have demonstrated that the HIV-1 transactivator protein,tat, induces apoptosis in T-lymphocyte cell lines, as well as in peripheral blood mononuclear cells, and stimulates a cascade
of events resulting in up-regulation of the potent immunosuppressive cytokine, transforming growth factor-β (TGF-β). In this
study we evaluated the ability of TGF-β to mediatetat induced apoptosis in T-lymphocyte cell lines. T-cells treated exogenously with either TGF-β1 or a combination of tat and
pan-specific TGF-β neutralizing antibodies showed little change in the amount of apoptosis. When treated with pan-specific
TGF-β neutralizing antibodies, Jurkat cells that stably expresstat protein (Jurkat-tat) showed only a modest decrease in apoptosis, while CEM-TART cells (CEM T-cells expressing both HIV-1tat andrev) demonstrated little change in the amount of apoptosis. In conclusion, we have demonstrated that TGF-β does not play a significant
role in mediatingtat induced T-cell apoptosis. 相似文献
92.
Commentary on acute renal failure in Asian region 总被引:1,自引:0,他引:1
93.
A M el-Shirbiny S Sadek A Owunwanne T Yacoub L Suresh H M Abdel-Dayem 《Nuclear medicine communications》1989,10(12):905-911
The relationship between the concentration of tissue glutathione (GSH) content and uptake of 99Tcm HMPAO in Sprague Dawley rats was investigated. The GSH content of rat tissue was depleted with diethyl-maleate (DEM) and the ratio of GSH in control to GSH depleted rat was approximately twice that in the brain, liver, kidney, spleen and lung. The GSH content in all the organs studied except the liver had no statistically significant relationship with the uptake of 99Tcm HMPAO. The apparent increase of radioactivity in the liver was due to longer retention of 99Tcm HMPAO. This longer retention was due to stasis of bile flow as confirmed by subsequent experiments in which cholecystokinin (CCK) was administered to GSH depleted rats and compared to the uptake of GSH depleted rats without injection of CCK. 相似文献
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The spectra produced by the acid treatment and alkaline treatment of streptomycin and dihydrostreptomycin have been investigated to obtain suitable methods for their determination. Mixtures of the two antibiotics have been successfully determined in the UV region. Thus, using the orthogonal function method, dihydrostreptomycin has been determined after acid treatment whereas streptomycin has been determined after alkaline treatment followed by immediate neutralization. 相似文献
99.
Remadi JP Marticho P Butoi I Rakotoarivelo Z Trojette F Benamar A Beloucif S Foure D Poulain HJ 《The Annals of thoracic surgery》2004,77(6):374-2175
PURPOSE: We studied a cohort of 150 patients operated on with a new cardiopulmonary bypass (CPB) system. This is the mini-extracorporeal circulation (MECC) system. DESCRIPTION: The MECC is a fully heparin coated closed-loop CPB system that includes a centrifugal pump and has a priming volume of 450 mL. Between March 2001 and September 2002, 150 consecutive patients were operated on using the mini-CPB (MECC) method. This includes 105 coronary artery bypass graft and 45 aortic valve replacement patients. The median age was 66.7 +/- 10.7 years with a gender ratio of 3.27 males to 1 female. EVALUATION: The 30-day operative mortality was 1.3%. The hemoglobin concentration was stable and perioperative transfusion was needed in only 6% of all patients. The renal and neuropsychiatric complications were less than 1%. CONCLUSIONS: In our experience, the MECC system is a reliable new concept for CPB with good clinical results. 相似文献
100.
OBJECTIVE: To conduct a meta-analysis of randomized controlled studies to evaluate abdominal ultrasound-guided embryo transfer compared to the clinical touch method. DESIGN: Meta-analysis. SETTING: Four studies performed in academic research centers in Barcelona, Vizcaya, Hong Kong, and Madrid. PATIENT(S): A total of 2,051 patients: 1,024 received ultrasound-guided embryo transfers and 1,027 received clinical touch method transfers. INTERVENTION(S): Fourteen studies were retrieved from the literature, but only four of them fitted our selection criteria. The meta-analysis was conducted using the RevMan software with the Peto-modified Mantel-Haenszel method and the fixed effect model. MAIN OUTCOME MEASURE(S): The primary outcome measures were the clinical pregnancy and ongoing pregnancy rates. The secondary outcome measures were the incidences of ectopic pregnancies, miscarriage rate, multiple pregnancies, and difficult transfers. RESULT(S): Compared to the clinical touch method, abdominal ultrasound-guided transfer significantly increased the clinical pregnancy rate and the ongoing pregnancy rate. There was no effect on the incidence of ectopic pregnancy, multiple pregnancy, or miscarriage rate. CONCLSUION(S): Ultrasound-guided embryo transfer increases the clinical pregnancy and ongoing pregnancy rates significantly compared to the clinical touch method. 相似文献