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It is well known that long-term use of steroids plays a decisive role in the development of glucose intolerance and diabetes mellitus (DM). Deflazacort, an oxazoline derivative of prednisolone, has been introduced as a potential substitute for conventional steroids in order to ameliorate glucose intolerance. We initiated a randomized study of conversion from prednisone to deflazacort in kidney transplantation (Tx) recipients presenting with pre-Tx or post-Tx DM to ascertain whether or not the switch to deflazacort would ameliorate the diabetic state. Forty-two recipients in the conversion group were compared with 40 patients on prednisone (the control group) in a prospective manner. The dose reduction of insulin or oral blood glucose-lowering agents, the adequacy of glucose control, and the development of side effects were the criteria for evaluating outcome. In the conversion group, patients were switched to deflazacort at a dose ratio of 6 mg deflazacort to 5 mg prednisone. During the mean follow-up period of 13.2 months, neither graft dysfunction nor acute rejection developed in the conversion group. Improvement in blood glucose control in the conversion group was noted. When the conversion group was stratified into pre- or post-Tx DM, promising effects were clearly evident in the post-Tx DM patients. More than 50 % dose reduction of blood glucose-lowering agents was possible in 42.3 % of post-Tx DM patients. In conclusion, it was readily possible to control blood glucose better in post-Tx DM recipients without seriously affecting the immunosuppressive activity after conversion to deflazacort. Received: 20 August 1996 Received after revision: 25 November 1996 Accepted: 6 December 1996  相似文献   
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OBJECTIVE: Previous studies have shown that decorin and biglycan account for over 70% of the proteoglycans (PGs) synthesized by human peritoneal mesothelial cells (HPMCs). Since these PGs are involved in the control of cell growth, cell differentiation, and matrix assembly, we investigated their turnover in cultured HPMCs. METHODS: Confluent HPMCs were metabolically labeled with [35S]-sulfate and the labeled products isolated from the cell medium and the cell layer characterized by sensitivity to bacterial eliminases. Experiments were undertaken with exogenous labeled decorin, and its metabolic state was studied. RESULTS: In a 24-hour labeling period, 75% of the newly synthesized chondroitin sulfate/dermatan sulfate (CS/DS) PGs appeared in the culture medium, the majority of which (90%) was decorin. In the cell layer, protein-free glycosaminoglycan (GAG) chains accounted for 21% of the total CS/DS at 24 hours and exhibited constant specific activity at 12-16 hours. The latter material was turned over with a half-life of approximately 2.5 hours. Exogenous decorin underwent receptor-mediated endocytosis and subsequent intracellular degradation. Uptake but not degradation could be inhibited by heparin. CONCLUSIONS: HPMCs are distinguished by a rapid turnover of decorin. A characteristic metabolic feature is the existence of a large intracellular pool of protein-free DS-GAGs. Understanding the control of decorin turnover in HPMCs might lead to delineation of its potential role in both the physiology and pathophysiology of the membrane in PD patients.  相似文献   
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朱友成    C.Prenant    C.Crouzel    池志强 《药学学报》1994,29(11):823-828
羟甲芬太尼(I)是一个新的高强度高选择性阿片μ受体激动剂。本文用cis-A-N-[1-(2-羟基-2-苯乙基)-3-甲基-4-哌啶基]-苯胺(II)或cis-N-[1-(苯甲酰甲基)-3-甲基-4-哌啶基]-苯胺(III)作为前体合成了[11C]-羟甲芬太尼,以便用正电子发射断层扫描(PET)来观察μ受体。通过水解cis-A-羟甲芬太尼(I)和cis-N-[1-(苯甲酰甲基)-3-甲基-4-哌啶]-N-苯基丙酰胺(cis-IV)的4-N-丙酰基分别获得II和III。溴乙烷的格氏试剂与回旋加速器产生的[11C]-二氧化碳反应后继而直接加入邻苯二甲酸二酰氯和2,6-二叔丁基吡啶生成同位素标记中间体[11C]-丙酰氯。[11C]-丙酰氯与OH-前体(II)反应后再经HPLC分离纯化直接得[11C]-羟甲芬太尼;[11C]-丙酰氯与酮-前体(III)反应后,再用硼氢化钠甲醇溶液处理,然后进行HPLC分离纯化得[11C]-羟甲芬太尼。两种方法均可获得ll.1~14.8GBq/μmol的特异性放射化学纯[11C]-羟甲芬太尼。总共耗时为40~50min(EOB)。  相似文献   
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A male, full-term baby with thrombocytopenia was born by a G3P2A1 mother who was not associated with autoimmune disease. Platelet antibody screening was positive by using lymphocytotoxicity test, platelet suspension immunofluorescence test and solid-phase red cell adherence test. The identified HLA antibody was of A2 specificity. It was confirmed by testing the mother's and the baby's sera against the lymphocytes and platelets of 10 HLA-A2-positive donors. The possibility of platelet-specific antibody as the cause of neonatal alloimmune thrombocytopenia was ruled out by testing against platelets of 10 HLA-A2-negative donors and the known platelet-specific antigens utilizing immobilized, purified platelet glycoprotein as targets. The mother's serum reacted strongly with both the father's and the baby's platelets and lymphocytes. This neonatal thrombocytopenia was most likely due to the maternal HLA antibody, which was induced by her antecedent gestations.  相似文献   
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羟甲芬太尼(1)是一个强效的镇痛剂和高亲和、高选择性的阿片μ受体激动剂。通过HPLC和1HNMR分析,cis-A-l被确定为由等量的cis-(+)-(3R,4S,2'S)-l和:cis-(—)-(3S,4R,2'R)-1组成的外消旋体,cis-B-l被确定为由等量的cis-(—)-(3R,4S,2'R)-1和cis-(+)-(3S/,4R,2'S)-1组成的外消旋体。  相似文献   
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Several likely precursors of schizophrenia have been identified. These range from possibly causative features, such as exposure to perinatal insults, to features that are the effects of an underlying vulnerability, such as abnormal childhood behaviors. Unfortunately none of these precursors is specific enough to be used in identifying individuals for targeted preventive treatment. A more useful strategy is to combine risk factors for psychotic disorders in a population seeking help for psychiatric problems. Thus, individuals who are possibly prodromal are identified. Research into this group has found high rates of onset of psychotic disorders, particularly schizophrenia, within a short time frame. Preliminary treatment trials suggest that symptoms can be reduced and psychosis onset possibly delayed or averted.  相似文献   
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