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The combination of the PCR technique and the synthetic oligonucleotides has proved to be a useful tool in the molecular analysis of HLA class II genes, allowing recognition of as little as a single nucleotide modification in the sequence of the gene. The molecules encoded by these genes have been associated with genetic control of the immune response and with susceptibility to certain diseases. Studies carried out in our laboratory have shown three patterns of humoral immune response in the human volunteers vaccinated with the synthetic protein SPf 66; high, intermediate and low responders. Approximately 73.3% of the low responders were serologically typed as HLA DR4 and 42% as DQw6. These results moved us to look for a subtype (Dw) correlation between the DR4 positive individuals and the different humoral immune response patterns. Using oligo-typing methods after previous amplification of the DR4 B1 exon, we subtyped 20 DR4 volunteers, classified as high, intermediate and low responders. We did not find any direct association between the HLA DR4 Dw special subtype in the high or low responders immunized with the SPf 66 vaccine.  相似文献   
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To assess the functional viability of platelets collected by standard apheresis techniques using the Fenwal CS-3000 "closed system" and stored in Fenwal PL 732 plastic bags for 5 days at room temperature with agitation, a number of in vitro parameters (pH, morphology, platelet volume distribution, osmotic recovery, aggregation, and platelet-associated IgG) were examined as a function of storage time. During the first 24 hours of storage, minimal changes were observed in the test parameters with the exception of ADP-induced aggregation (75% decrease [10 uM], 84% decrease [5 microM]). Significant differences were observed between fresh (day 0) and 5-day-old platelet concentrates in all parameters except median platelet volume. These observed changes in in vitro test parameters with storage time are similar to those previously observed for comparably stored random single-donor platelet concentrates. Thus, the "closed-system" PL 732 apheresis platelet concentrates would be expected to be as effective in vivo as random single-donor platelet concentrates, while minimizing recipient exposure to transmissible agents of infectious disease.  相似文献   
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As the world's most populous country, China is likely to have the highest number of people with intellectual disabilities (ID) in the world. As many people with ID are susceptible to serious and persistent behavior problems, research by Chinese scientists on this public health issue is needed. However, there are only very few reliable Chinese-language behavior assessment instruments for problem behaviors. To fill this gap we translated the Behavior Problems Inventory-01 (BPI-01; Rojahn, Matson, Lott, Esbensen, & Smalls, 2001) into Chinese. The BPI-01 is an informant-based behavior rating instrument that was designed to assess self-injurious behavior (SIB), stereotyped behavior, and aggressive/destructive behavior in individuals with ID. We then assessed the behavior of 222 children and young adults (age range 1.5–21.5 years) with or at risk for ID from three special needs service programs in mainland China. Teachers or staff members, respectively, served as respondents. The Chinese version of the BPI-01 showed good reliability (internal consistency) and good factor validity tested by confirmatory factorial analysis. We conclude that the Chinese version of the BPI-01 can be used for research and clinical evaluation of Chinese children and adolescents with ID.  相似文献   
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目的探讨构建BCR-ABL SH3-T79Y突变体(简称SH3-T79Y突变体)的重组腺病毒载体及其对白血病耐药细胞株K562/G01细胞凋亡的影响。方法以p Mig210质粒为模板,用重叠延伸PCR扩增SH3-T79Y突变体片段,将其克隆入重组腺病毒载体,通过鉴定、包装、扩增后得到含SH3-T79Y突变体的重组腺病毒。将重组腺病毒感染白血病K562/G01细胞株,测定其感染效率,瑞氏染色检查细胞形态学,流式细胞术检测细胞凋亡,Western blot检测BCR-ABL、Crk L磷酸化及总蛋白水平。结果重组腺病毒载体构建成功。SH3-T79Y突变体转染K562/G01细胞株72 h效率大于80%,可见明显的凋亡小体、核聚集等凋亡现象,凋亡率为32.46%,较对照组显著增加(P0.05);明显抑制BCR-ABL和Crk L的磷酸化水平,降低BCR-ABL总蛋白表达(P0.05)。结论成功构建SH3-T79Y突变体重组腺病毒载体,并证实其通过抑制BCR-ABL及底物Crk L磷酸化水平促进K562/G01细胞凋亡。  相似文献   
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The serologic and viral profiles of 24 patients who presented with acute hepatitis B virus (HBV) infection were studied. Although in rare cases, HBV-DNA was detectable before hepatitis B surface antigen (HBsAg) and e antigen (HBeAg), in the majority the viral proteins appeared first. In acute hepatitis followed by recovery, as IgM anti-HBc (hepatitis B core antigen) titres rose, the level of HBV replication fell and serum transaminases became elevated. In patients progressing to chronic HBV infection, IgM anti-HBc titres rose early, viral replication was initially low but continued to rise as the serum transaminase levels became elevated. 7S IgM anti-HBc, although present in the phase of established chronic HBV infection, was not found in the early phase of the chronic infection. Thus this antibody appears to be a consequence of, rather than a causative factor in, chronic HBV infection.  相似文献   
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