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41.
Blood group studies disclosed mosaicism of the red cells in a healthy male Negro donor who was subsequently also found to have mosaicism of skin and bone marrow with respect to XX-XY chromosomal constitution and whose skin showed unequal pigmentation. The two red cell populations were unequal in numbers with a ratio of approximately 10:1. The major population was group A, Jka negative and showed the sickling trait in wet films and by electrophoresis. The minor population was group B, Jka positive, did not sickle and contained only hemoglobin A. Both red cells were Lea positive despite the fact that the propositus was a secretor. However, only A substance was secreted and it was demonstrated by salivary studies and with the help of complete family studies, that the minor genetic product which had produced the group B erythrocytes represented the gene contribution se se and was the source of Lea substance sufficient to coat both red cell populations. The family studies showed that the propositus had received a 2 allele contribution from each parent and was therefore the result of double fertilization of a double egg nucleus presumably an ovum and a polar body.  相似文献   
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目的:干细胞移植后可以通过分化为心肌细胞、减少心肌重构等方面发挥改善心功能的作用。观察急性心肌梗死后进行骨髓单个核细胞移植对相关细胞因子的调节作用,探讨干细胞发挥改善心脏重构的可能机制。方法:实验于2006-01/2007-02在福建省高血压研究所完成。①实验材料:清洁级SD大鼠由上海实验动物公司提供。②实验方法:取SD大鼠骨髓,分离出单个核细胞,以DAPI标记骨髓单个核细胞。取体质量200~250g雄性SD大鼠24只,建立急性心肌梗死模型后,随机分为2组,实验组从股静脉注入同种异体大鼠骨髓单个核细胞1.0×107,对照组注入等量的生理盐水。③实验评估:于移植后4周采用免疫组组织化学法检测DAPI阳性细胞、肌钙蛋白阳性细胞、基质细胞源性因子1、转化生长因子β及大鼠心功能改变。结果:24只大鼠均进入结果分析。移植后4周实验组基质细胞源性因子1表达较对照组明显升高,转化生长因子β表达较对照组下降;实验组在免疫荧光显微镜下可观察到DAPI和肌钙蛋白阳性细胞,心功能较对照组明显改善。结论:骨髓单个核细胞移植改善急性心肌梗死大鼠心功能的同时伴有基质细胞源性因子1表达增加及转化生长因子β表达下降。  相似文献   
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DNA damage is important in the pathogenesis of esophageal adenocarcinoma (EA). Polymorphic variants in DNA repair genes may be modifiers of the risk of EA through their role in altering human host response to gastroesophageal acid reflux, a well-described risk factor for EA. We studied the role of genetic polymorphisms of two key DNA repair genes, xeroderma pigmentosum group D (XPD) (Asp312Asn and Lys751Gln) in the nucleotide excision repair (NER) pathway and X-ray repair cross-complementing gene 1 (XRCC1) (Arg399Gln) in the base excision repair (BER) pathway, in the development of EA in 183 cases and 336 frequency-matched controls for age, gender and race. Genomic DNA was extracted from blood samples. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained from logistic regression models, adjusted for body mass index at 18 years of age, smoking and alcohol exposure. The variant genotypes of XPD Lys751Gln polymorphism were associated with a higher risk of EA; the adjusted OR comparing Gln/Gln + Lys/Gln with Lys/Lys was 1.49 (95% CI: 1.02-2.14). Although no significant relationships were found for the XRCC1 Arg399Gln polymorphism alone, this polymorphism did modify the relationship between XPD Lys751Gln and EA risk; when both polymorphisms were evaluated together, adding the number of variant alleles of the two polymorphisms resulted in a significant trend (trend test, P = 0.008); compared with individuals with no variant alleles (n = 88), the adjusted ORs of developing EA are 1.49 (95% CI: 0.88-2.59), 1.69 (95% CI: 0.98-2.96) and 2.58 (95% CI: 1.31-5.06) for one (n = 195), two (n = 166) and three or four variant alleles (n = 70), respectively. No relationships were found for the XPD Asp312Asn polymorphism. We conclude that combined NER and BER pathways are important to the development of EA.  相似文献   
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PURPOSE: Autologous stem-cell transplantation has been shown to be a curative procedure for a variety of leukemias and lymphomas. Most transplants require RBC and platelet support. We report the ability to perform autologous transplantation without blood-product support. SUBJECTS AND METHODS: In this study, we treated 26 patients with religious objection to blood products with autologous stem-cell support without the use of any blood products. Patients received a combination of granulocyte colony-stimulating factor (G-CSF), erythropoietin, and interleukin-11 or G-CSF alone to mobilize stem cells. Post-transplant patients received intravenous iron, erythropoietin, G-CSF, and epsilon aminocaproic acid. RESULTS: There were two major bleeding complications (8%), with two treatment-related deaths (8%). There were three minor bleeding complications (12%). The median fall in hemoglobin level was 4.7 g/dL; the median hemoglobin level 30 days after transplantation was 9.2 g/dL. The median total number of days with platelet count less than 10 x 10(9)/L was 4 days; the median days to platelet recovery greater than 20 x 10(9)/L was 12 days. CONCLUSION: Autologous stem-cell transplantation can be performed safely without the use of any blood products.  相似文献   
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