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51.
Bone marrow transplant recipients are at risk for acquiring hepatitis C infection from the donated marrow. Twelve patients who were hepatitis C virus (HCV) RNA-negative pretransplant received marrow from anti-HCV seropositive donors. HCV RNA was present in the sera of seven of these donors. After transplant, serial serum specimens were obtained from all marrow recipients for determination of HCV RNA and aminotransferase levels. All seven recipients of marrow from HCV RNA-positive donors were HCV RNA-positive after marrow infusion; none cleared virus from the serum. All five recipients of marrow from anti-HCV seropositive, HCV RNA-negative donors remained free of HCV RNA in serum up to day 100. Abnormal serum aminotransferases were common in both HCV RNA- negative and HCV RNA-positive marrow recipients. One HCV-infected recipient developed marked elevation in aminotransferases after immunosuppressive drugs were stopped. We conclude that the presence of HCV RNA in the serum of marrow donors is an accurate predictor of HCV infection in marrow recipients. The acute infection was subclinical in all patients. The long-term risk of chronic hepatitis C virus infection in these patients remains to be determined.  相似文献   
52.
BACKGROUND & AIMS: Murine autoimmune gastritis, induced by day-3 thymectomy, is characterized by cellular infiltrates and circulating autoantibodies to gastric hydrogen/potassium adenosine triphosphatase. The aim of this study was to analyze the cellular infiltrates and cytokines in autoimmune gastritis. METHODS: Stomachs and blood samples from day-3 thymectomized BALB/c mice were obtained from 2 to 12 weeks after thymectomy for analysis. RESULTS: At 4 weeks, the gastritic infiltrates were composed of macrophages and CD4+ T cells, accompanied by major histocompatibility complex class II expression on gastric epithelial cells. Mucosal B cells, scant at 4 weeks, were abundant at 8 weeks, coincident with the peaking of autoantibodies to gastric hydrogen/potassium adenosine triphosphatase. CD8+ T cells increased marginally during the 12 weeks. Mononuclear cells from diseased stomachs transferred gastritis to nu/nu recipients. At 4 weeks, interleukins 2, 3, 5, 6, and 10; interferon gamma; tumor necrosis factor alpha; and granulocyte-macrophage colony-stimulating factor were detected in gastritic mucosa, but interleukin 4 was not. CONCLUSIONS: The early lesion of autoimmune gastritis is composed of macrophages and CD4+ T cells with major histocompatibility complex class II expression in gastric epithelial cells. Autoantibody production is a late event. Our results are consistent with a lesion mediated by CD4+ T cells producing a mix of Th1- and Th2-type cytokines. (Gastroenterology 1996 Jun;110(6):1791-802)  相似文献   
53.
Increasing the expression of the gamma globin genes is considered a useful therapeutic approach to the beta globin diseases. Because butyrate and alpha-amino-n-butyric acid (ABA) augment gamma globin expression in normal neonatal and adult erythroid progenitors, we investigated the effects of sodium butyrate and ABA on erythroid progenitors of patients with beta thalassemia and sickle cell anemia who might benefit from such an effect. Both substances increased fetal hemoglobin (Hb F) expression in Bfu-e from 7% to 30% above levels found in control cultures from the same subjects with sickle cell anemia. The fraction of cultured erythroblasts producing Hb F increased more than 20% with sodium butyrate treatment in 70% of cultures. In most cultures, this produced greater than 20% total Hb F and greater than 70% F cells, levels which have been considered beneficial in ameliorating clinical symptoms. Alpha: non-alpha (alpha-non-alpha) imbalance was decreased by 36% in erythroid progenitors of patients with beta thalassemia cultured in the presence of butyrate compared with control cultures from the same subjects. These data suggest that sodium butyrate may have therapeutic potential for increasing gamma globin expression in the beta globin diseases.  相似文献   
54.
BACKGROUND: One of the most recognizable features of psychopathy is the reduced ability to successfully learn and adapt overt behavior. This might be due to deficient processing of error information indicating the need to adapt controlled behavior. METHODS: Event-related potentials (ERPs) and behavioral components of error-monitoring processes were investigated in 16 individuals with psychopathy and in 18 healthy subjects. A letter version of the Eriksen flanker task was used in two conditions. The first condition (normal condition) required participants to press one of two buttons depending on the identity of the target stimulus. The second condition (signaling condition) required them to signal each time they had committed an error by making a second press on a signaling button. Early stages of error monitoring were investigated by using the error-related negativity (ERN/Ne) and post-error slowing as indexes. Later stages were explored by examining the error positivity (Pe) and signaling rates. RESULTS: Both groups showed similar ERN amplitudes and amounts of post-error slowing. The psychopathic group exhibited both reduced Pe amplitudes and diminished error-signaling rates compared with the control group. CONCLUSIONS: Individuals with psychopathy show intact early error processing and automatic behavioral adaptation but have deficits in later stages of error processing and controlled behavioral adaptation. This is an indication that individuals with psychopathy are unable to effectively use error information to change their behavior adequately.  相似文献   
55.
Concurrent chemotherapy and radiation (CT/RT) for localized oesophageal cancer can cause life-threatening myelo-suppression. This non-randomized study examines 95 patients from three Australasian centres treated on the Trans-Tasman Radiation Oncology ‘definitivechemoradiation ‘ study. Duration of fluorouracil infusion and patient age were independently predictive of myelotoxicity after the first cycle of CT/RT. Overall rates of grade III and IV neutropaenia were 23% and of thrombocytopaenia 8% following the first cycle of chemotherapy. Five neutropaenic septic episodes followed the first cycle and six the second. All five patients recovered after the first cycle but there were four treatment-related deaths occurring after the second cycle of CT/RT. Recommendations are made concerning initial dosing, dose reductions and delays to minimize adverse patient outcomes from myelosuppression.  相似文献   
56.
57.
樟叶胡椒中新木脂素成分的研究   总被引:3,自引:0,他引:3  
自胡椒科胡椒属植物樟叶胡椒(Piper polysyphorum C. DC)中分离到六个新木脂素(neolignans)类化合物,经光谱(UV,IR,MS,1H-NMR,13C-NMR,2D-NMR,CD)分析及衍生物制备,确定Ⅱ为新化合物,即threo-△7-7-羟基-3,4,5,3′,5′-五甲氧基-8-O-4′-新木脂素,为一对对映体,命名为樟叶素(polysyphorin),Ⅰ,Ⅲ,Ⅳ为新的对映体,分別为(+)-virolongin,(+)-grandisin及(+)-lancifolin D.化合物Ⅴ为南藤素(wallichinine),Ⅵ为山蒟素D(hancinone D)。血小板活化因子(PAF)受体结合实验及PAF引起的血小板聚集实验证明化合物Ⅰ~Ⅴ具有明显的抑制活性。  相似文献   
58.
赛庚啶对氧自由基的清除作用   总被引:18,自引:0,他引:18  
辛洪波  张宝恒 《药学学报》1993,28(3):161-165
赛庚啶(Cyp)对Fenton反应生成的·OH有较强的直接清除作用(EC50为54μmol/L),并明显抑制·OH的生成速率(IC50为22 μmol/L),且作用明显比·OH特异性清除剂甘露醇强(其EC50和IC50分别为22.7 mmol/L和10.7mmol/L)。Cyp对大鼠腹腔多形核白细胞(PMNs)产生的O2也有一定的清除作用,其IC50为179 μmol/L。提示Cyp的抗心肌损伤作用可能至少部分与其清除氧自由基作用相关。  相似文献   
59.
三七中人参三醇甙(PTS)2.5μg/ml及5.0μg/ml均能明显延长羊心浦氏纤维动作电位时程(APD)包括APD_(30),APD_(50),APD_(90),对动作电位幅度(APA)无明显影响。双微电极法电压钳实验证明,PTS能明显抑制羊心浦氏纤维延迟整流钾电流(I_x)的峰值,且此种抑制作用呈时间及剂量依赖性。揭示PTS通过阻滞延迟整流钾通道而延长APD。  相似文献   
60.
Over-the-counter emergency contraception: a feasible option   总被引:1,自引:1,他引:0  
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