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191.
A soluble allogeneic effect factor (AEF) was produced by using H-2 congenic mouse strains and a serum.free cell culture medium. An AEF derived from untreated activated responder cells and irradiated stimulator cells provided helper cell function in a primary and secondary antibody response for both T-cell-depleted responder B cells and stimulator B cells. This interaction may be determined by genes situated in the I-A and I-B regions: additional K-region control was not excluded. Ia antigens, but neither H-2 nor Ig determinants are molecular constituents of AEF. The active components of this AEF consist, in part, of Ia antigens derived from both the activated responder cell population and irradiated stimulator cell population. An AEF derived from Ia negative responder cells and irradiated T-cell- depleted stimulator cells helps a secondary antibody response of T-cell- depleted stimulator B cells but not responder B cells. This genetically restricted AEF contains Ia antigens determined by the stimulator haplotype but not the responder haplotype. The priming antigen, DNP- keyhole limpet hemocyanin, is not a component of restricted AEF. The data suggest that restricted AEF may be a product of a stimulator B cell and/or macrophage. They support the hypothesis that the recognition by allogeneic T cells of Ia antigens on B cells activates the B cell to IgG antibody production.  相似文献   
192.
The death of a neonatal infant following cardiac surgery and the transfusion of packed red cells (RBCs) with high plasma potassium levels is reported. The patient had been diagnosed at 2 weeks of age as having multiple cardiac malformations. During cardiopulmonary bypass surgery, multiple units of packed RBCs less than 5 days old were transfused. In response to a "stat" order and after depletion of stock units prepared for neonatal usage, a 32-day-old unit of packed RBCs was issued for transfusion. After approximately 60 mL was rapidly transfused from this unit, the patient experienced cardiac arrest. Serum potassium concentration after transfusion and before death was 8.9 mmol per L. Plasma potassium concentration in the remainder of the transfused packed RBC unit was approximately 60 mmol per L. A model was created to calculate the posttransfusion plasma potassium concentration, and close correlation was found between the model and the observed potassium concentration, which assumes that the potassium load had not yet been distributed to the extravascular and intracellular fluid compartments. It is concluded that the transfusion of relatively large volumes of RBCs be limited to fresh packed RBCs or to packed RBCs that have been saline washed, to minimize the complications of electrolyte disturbances.  相似文献   
193.
Background Previous studies, especially in North America, have shown that socio-economic factors may influence the prognosis for patients with HIV. This study was performed in order to determine if European or non-European origin influence provision of health-care and survival among HIV patients in Europe.
Methods Fifty HIV clinics in 17 European countries are involved in a European prospective, observational multicentre study. In total, 7230 consecutive patients with HIV attending a routine clinic visit were included in the study. Data on demographics, treatment and laboratory results were collected at time of recruitment into the study and thereafter every 6 months.
Results The median CD4+ lymphocyte count at AIDS diagnosis was 60/mm3, and was similar for all ethnic groups ( P  = 0.87, Kruskall–Wallis test). The median terminal CD4+ lymphocyte count was 17/mm3 and, again, there was no significant difference between continents of origin ( P  = 0.35, Kruskall–Wallis test). Antiretroviral drugs were initiated at similar median CD4+ lymphocyte counts and there was no statistically significant difference in survival after a diagnosis of AIDS.
Conclusions AIDS was diagnosed at the same level of immunodeficiency independent of European or non-European origin and antiretroviral drugs were provided at similar levels of immunodeficiency. No differences in survival depending on continent of origin was found. In spite of these encouraging findings concerns remain that belonging to an ethnic minority can be an obstacle in getting into contact with treatment facilities and thus benefiting from developments in the management of HIV.  相似文献   
194.

Introduction  

Absolute lymphocytopenia has been reported as a predictor of bacteremia in medical emergencies. Likewise, the neutrophil-lymphocyte count ratio (NLCR) has been shown a simple promising method to evaluate systemic inflammation in critically ill patients.  相似文献   
195.
目的:探讨烧伤再生疗法(BRT)和湿润烧伤膏(MEBO)治疗烧伤的临床效果.方法:该试验为前瞻性、单一中心临床研究,研究对象为2009年9月和2010年3月间筛选的10名年龄在3个月至75岁之间的浅Ⅱ度~Ⅲ度烧伤患者,全程采用BRT和MEBO治疗,观察记录创而75%愈合时间、创面100%愈合时间、创面感染率、疼痛指数、平均住院时间、过敏反应率,并拍摄照片进行治疗前后的对比观察.结果:创面75%和100%愈合的平均时间分别为27.3天和59.0天;换药时的平均疼痛指数为4;住院时间最短9天,最长151天,平均住院时间为57.1天;细菌感染率为10%;没有发现过敏反应.结论:在本研究中,有些创面本是需要接受植皮手术的,但是经MEBO继续治疗4周~6周后能够成功实现上皮化再生愈合.因此,MEBO治疗烧伤的有效性毋庸置疑.  相似文献   
196.

Background  

The quasispecies nature of HCV may have important implications for viral persistence, pathogenicity and resistance to antiviral agents. The variability of one of the viral proteins, NS5A, is believed to be related to the response to IFN therapy, the standard treatment for infection. In this study we analyzed the quasispecies composition of NS5A protein in patients infected with HCV genotype 3a, before IFN therapy.  相似文献   
197.
198.
199.
肝靶向抗病毒药NGA-ACV的制备及其趋肝性   总被引:5,自引:0,他引:5  
以无唾液酸糖蛋白受体(asialoglycoproteinreceptor,ASGPR)的特异性配体半乳糖基拟糖白蛋白(neoglycoalbumin,NGA)为载体,通过丁二酰基桥将抗病毒药无环鸟苷(acyclovir,ACV)与NGA偶联,得到肝靶向抗病毒药NGAACV。差热分析和高效液相色谱分析结果表明,NGAACV是共价键偶联物,且在血液中稳定性很好。将偶联物用131I标记后进行家兔放射性显像比较研究。结果,高、低药密度NGAACV的肝脏放射性分别是全身放射性的81.6%和86.6%,其趋肝性无明显差别。研究小鼠体内高药密度131INGAACV的分布,在5min时肝脏放射性达到峰值,为注入量的81.7±10.4%。受体竞争抑制实验表明NGAACV的肝靶向机理为受体介导的主动靶向过程。初步体外抗乙肝病毒比较研究表明,NGAACV较ACV的抗病毒剂量有明显降低。  相似文献   
200.
Large-core biopsy guns: comparison for yield of breast tissue   总被引:1,自引:0,他引:1  
  相似文献   
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