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1.
Hearts were implanted heterotopically into the hemocoel of NIH albino Biomphalaria glabrata from three xenogeneic donor snails, including two New World (B. obstructa, B. tenagophila) and one Old World (B. alexandrina) species, as well as from wild type allogeneic donors. Recipients were examined histologically at 1, 3, 7, 10, 15, 30, 60, 120, and 180 days postimplantation (PI). Grafts from all four donor species were temporarily infiltrated by recipient hemocytes at early intervals PI and in most instances also became encapsulated. Furthermore, the grafts subsequently showed histopathological alterations and abnormal heartbeat relative to preimplantation controls. However, hemocytic reactions eventually subsided, the implants remained structurally intact, and implant myocardial cells both maintained high levels of intracellular glycogen and continued to contract rhythmically for 6 months. No major differences occurred in fates among different xenografts, or between xenografts and allografts. Our observations of prolonged xenograft survival differ from those of previous investigators, most of whom have reported rapid destruction of implanted xenogeneic tissues in molluscs.  相似文献   
2.
采用顺序特异引物聚合酶链反应技术(PCR-SSP)检测我国汉族人群HLA-DRB1*04等位基因亚型频率,并与白种人群进行比较。利用5′端公用引物与3′端8个特异性引物进行PCR反应,可准确分辨出11个DRB1*04等位基因,耗时4小时,无假阳性和假阴性结果。85份随机样本的分型结果显示,我国汉族人群DRB1*04基因亚型的频率与白种人之间存在非常显著性差异。  相似文献   
3.
Analysis of retrospective data, obtained on 216 patients from 27 centers transplanted across some form of positive lymphocyte cross-match in a noncurrent serum, revealed that actuarial 1-yr graft survival was 69% in first transplants and 53% in recipients of second or subsequent transplants. Graft outcome did not correlate with peak antibody levels, change in antibody from peak to current, remoteness in time of the most recent positive serum, the number or timing of sera cross-matched, the technique or target cell cross-matched, or the degree of positivity of the most recent positive serum. Although a concurrent control population was not available, these results support the concept that acceptable graft survival can be achieved despite a positive cross-match with noncurrent sera.  相似文献   
4.
目的探索临床应用巢式序列特异性引物聚合酶链式反应(PCR-SSP)方法检测HLA单倍体相合供受者间母胎微嵌合状态的可行性。方法选取25对拟行HLA单倍体相合造血干细胞移植治疗的实体肿瘤患者及其供者,供受者为母子关系15例,父子关系10例。采集供受者外周血提取基因组DNA,采用巢式PCR-SSP方法检测患者外周血中供者来源的HLA-DRB1位点,并计算母胎微嵌合阳性率。随机选取经巢式PCR-SSP证实嵌合阳性和阴性且供受者性别不同的患者各4例,采用荧光原位杂交(FISH)技术进行重复检测,并与巢式PCR-SSP方法的检测阳性率进行比较,同时采用噻唑蓝法检测这8例患者分别与其亲缘供者和HLA完全不相合无关第3人之间的混合淋巴细胞增殖反应(MLR),并计算增殖指数(SI)。结果巢式PCR-SSP方法灵敏度可高达0.001%,并具有较好的特异性。巢式PCR-SSP检测显示,在母子移植关系患者中母胎微嵌合阳性检出率为40%(6/15),而在父子移植关系患者中母胎微嵌合阳性检出率为0。巢式PCR-SSP方法的检测灵敏度与FISH技术相比明显增高,其检测阳性率分别为50%(4/8)和12.5%(1/8)。MLR检测显示,嵌合阳性患者对其亲缘供者和无关第3人外周血单个核细胞(PBMC)的SI分别为(0.949±0.023)、(1.320±0.095),嵌合阴性患者对其亲缘供者和无关第3人PBMC的SI分别为(1.133±0.036)、(1.245±0.069);嵌合阳性患者对其亲缘供者PBMC的增殖反应强度与嵌合阴性患者相比明显降低(P=0.001),并且也显著低于其对无关第3人PBMC的增殖反应强度(P=0.003)。结论巢式PCR-SSP方法灵敏度高、特异性好,适用于临床HLA单倍体相合供受者间母胎微嵌合状态的快速检测。  相似文献   
5.
目的:检测新工艺制备的β-磷酸三钙(β-TCP)的生物相容性,方法:将自制β-TCP植入小鼠股后肌袋。术后24,72h,1,2,4,8周分别取材做组织学检查,2,4周取材部分标本做扫描电镜(SEM)观察。结果:随着时间推移,β-TCP逐渐被纤维组织分割包围,但是无软骨,骨和坏死组织形成,结论:新工艺制备的β-TCP具有良好的组织相容性。  相似文献   
6.
Summary Indicator cells — tanned, surface stabilized sheep erythrocytes — were incubated for 1 h in supernatants of 3 h MLCs. Their electrophoretic mobility was measured by an analytical, carrier free electrophoresis system. The change in their mobility compared with an appropriate control was calculated in per cent and correlated with the conventional measured MLR-cpm. The correlation of the two quantities is statistically highly significant (p<0.01). Furthermore, the difference of the electrophoretic mobility values of the group of HLA-D-identical and the groups of HLA-D-haploidentical or -different donors is significant beyond the 1 level (p<0.0005). Our method enables, therefore recognition of a positive or negative MLC after only 4 h. Typing for HLA-D-determinants seems to be possible. This could be of great importance for histocompatibility testing and organ transplantation.  相似文献   
7.
We describe the analysis of the Major Histocompatibility Complex (MHC) class II polymorphism in Mexican Mestizo population. The study provides the HLA-DRB1, DQA1 and DQB1 allele frequencies in 99 Mexican Mestizos. DNA from these individuals was typed by PCR followed by hybridization using sequence specific oligonucleotides (PCR-SSO). The relationship with other worldwide populations was studied by using HLA data from 69 different populations and calculating neighbor-joining dendrograms and correspondence multidimensional values. The highest frequencies were for DRB1*0802 (allele frequency = 0.151), DRB1*0701 (allele frequency = 0.111) and DRB1*0407 (allele frequency = 0.106). Among the eight DQA1 alleles detected, the most frequent were DQA1*03011 (allele frequency = 0.257), DQA1*0501 (allele frequency = 0.227) and DQA1*0401 (allele frequency = 0.166). Twelve DQB1 alleles were found and four of them, DQB1*0302 (allele frequency = 0.237), DQB1*0301 (allele frequency = 0.176), DQB1*0201 (allele frequency = 0.166) and DQB1*0402 (allele frequency = 0.166) showed the highest frequencies. The haplotype DRB1*0802-DQA1*0401-DQB1*0402 (0.151) predominated clearly, followed by DRB1*0701-DQA1*0201-DQB1*0201 (0.111) and DRB1*0407-DQA1*03011-DQB1*0302 (0.101). Both genetic distances and correspondence analyses showed that Mexicans clustered with Amerindian population. These results suggest that the Mexican Mestizo population be principally characterized by haplotypes presents in Amerindian and Caucasian populations with a low frequency of Black haplotypes. In summary, the HLA class II haplotype frequencies demonstrated the tri-racial component existing in Mexican Mestizos.  相似文献   
8.
The human major histocompatibility complex (MHC) on chromosome 6 encodes three classical class-I genes: human leukocyte antigens (HLA) A, B, and C. These polymorphic genes encode a 43- to 45-kDa cell surface glycoprotein that, in association with the 12-kDa β2-microglobulin molecule, functions in the presentation of nine amino acid peptides to the T-cell receptor of CD8-bearing T lymphocytes and killer inhibitory receptors on natural killer cells. In addition to these ubiquitously expressed, polymorphic proteins, the human genome also encodes several nonclassical MHC class-I-like, or class Ib, genes that, in general, encode nonpolymorphic molecules involved in various specific immunological functions. Many of these genes, including CD1, the neonatal Fc receptor for IgG, HLA-G, HLA-E, the MHC class-I chainrelated gene A, and Hfe, are prominently displayed on epithelial cells, suggesting an important role in epithelial cell biology.  相似文献   
9.
目的探讨夫妇双方HLA—DQA1/DQB1组织相容位点匹配个数及丈夫或第三方淋巴细胞免疫治疗(LIT)对复发性流产患者封闭抗体水平的影响。方法选取2010年10月至2012年6月在本院确诊为不明原因复发性流产患者177例。治疗前分别检测患者夫妇双方HLA—DQA1和HLA—DQB1基因型,根据血液传播疾病筛查结果选择丈夫(140例)或第三方健康个体(37例)淋巴细胞经皮内注射免疫治疗3次,分别在治疗前和治疗后以流式细胞术交叉配型实验(FCXM)检测抗丈夫淋巴细胞抗体(APLA)和抗第三方淋巴细胞抗体(ATLA)的水平。结果HLA—DQA1/DQB1组织相容性匹配程度不同的夫妇在LIT后APLA无统计学差异(P〉O.05);丈夫和第三方LIT诱导产生的封闭抗体(包括APLA和ATLA)均显著高于治疗前(P〈O.05);丈夫LIT诱导产生的APLA显著高于第三方LIT(P~0.05);第三方LIT诱导产生的ATLA显著高于APLA(P〈O.05)。结论HLA—DQA1/DQB1组织相容性增高在LIT中对封闭抗体产生无影响。在封闭抗体生成水平上,丈夫LIT效果优于第三方uT。  相似文献   
10.
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