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101.
HLA antigens in schistosomal hepatic fibrosis patients with haematemesis   总被引:2,自引:0,他引:2  
H. Abaza    L. Asser    M. El  Sawy  S. Wasfy    L. Montaser    M. Hagras  A. Shaltout 《Tissue antigens》1985,26(5):307-309
20 patients of schistosomal hepatic fibrosis and splenomegaly (SHF) with and without haematemesis were examined. Typing for HLA-A, B and C antigens in these patients were compared with those of a group of 100 Egyptian controls. The study showed the presence of an association between HLA-A1 and B5 antigens in SHF cases. However, there was no significant association between HLA antigens and SHF cases with haematemesis.  相似文献   
102.
103.
Lymphocytes of thymus, spleen, peripheral blood (PB) and bone marrow (BM) collected from adult lizards, Chalcidesocellatus were cultured for 24 hr in the presence of 10?3M hydrocortisone acetate (HC) in order to assess the effect of in vitro HC on lizard T and B cell viability. The results indicated that HC induced stepwise, time-dependent mortality of the majority of thymocytes carrying T cell specific antigen(s) (TSA), 30–50% of T cells of spleen, PB and BM, and of a proportion of splenic B lymphocytes. Administration of 1 mg/g body weight HC to adult Ch. ocellatus lead to depletion of all TSA+ thymocytes. In contrast, T lymphocytes in the peripheral lymphoid compartments revealed both sensitivity and resistance to HC; similarly, B lymphocytes constituted susceptible and resistant subpopulations.  相似文献   
104.
Longitudinal studies in Sudan show ethnic differences in incidence and clinical phenotypes associated with Leishmania donovani. Immunologically, bias in type 1 vs type 2 cytokine responses is important. To determine whether polymorphisms at IL4/IL9 or IFNGR1 contribute to susceptibility, we examined 59 multicase families of visceral leishmaniasis (VL) with/without post Kala-azar dermal leishmaniasis (PKDL). Multipoint nonparametric analysis (Allegro) linked IL4/IL9 to VL per se (P=0.002). Transmission disequilibrium testing with robust variance estimates confirmed association in the presence of linkage between VL per se and IL4 (P=0.008) but not IL9. Stepwise logistic regression analysis showed both IL4RP2 and IL4RP1 markers contributed significantly to the association, suggesting a common disease-associated haplotype. In contrast, IFNGR1 was linked (P=0.031) and associated (P=0.007) to PKDL but not VL or VL per se. Hence, polymorphism in a type 2 cytokine gene influences underlying susceptibility to VL, whereas IFNGR1 is specifically related to susceptibility to PKDL.  相似文献   
105.
In the case of water soluble polymers, the use of size exclusion chromatography (SEC) for the determination of the molecular weight involves numerous difficulties. In order to analyse and determine the molecular weight of acrylic acid telomers we have first tried to obtain a satisfactory and reproducible separation. In this particular case, low-molecular-weight standards are not commercially available. Therefore, we decided to prepare standards based on acrylic acid, either by telomerization with a fluorinated telogen or by polymerization with an initiator bearing a fluorinated group. A calibration curve was obtained from the standards. Telomers of acrylic acid with thioglycolic acid were analysed. This is a general method for determination of DP n by SEC when there is no standard for the polymers. It can be used in a wide range of DP n from 1 to 700.  相似文献   
106.
In order to develop a biodegradable interlocking nail for fracture fixation, hydoxylapatite pins and paste were implanted in the femoral bone of rats. A distal fracture was performed. The union and the tissue reaction to hydroxylapatite versus stainless-steel rods were studied after 15 days, 1, 2 and 6 months implantation. Metal pins induced a union. Hydroxylapatite pins (Ossatite) did not prevent callus formation, but did not lead to consolidation in all cases due to weakness of gelatin matrix binding the apatite particles together. The biocompatibility of material is satisfactory and the osteo-inductive properties of hydroxylapatite was confirmed. With injectable Ossatite , we could not obtain rat femoral fracture consolidation. We can confirm good biomaterial tolerance in bone which contrasts with important soft tissue reactions. Use of such material should be carefully limited to filling intra-osseous cavities.  相似文献   
107.
108.
An 18- to 20-nm virus particle was isolated from the Olson strain of quail bronchitis, an avian adenovirus. On density gradient separation the small virions were primarily found at densities of 1.39 and 1.42 g/cm(3). The majority of the infectious particles were at the heavier density. The virus had a hexagonal outline and contained single-stranded deoxyribonucleic acid. It was resistant to heating at 56 C for more than an hour and was not inactivated by treatment with chloroform or low pH. Purified virus did not agglutinate erythrocytes of various avian and mammalian species. Replication of the small particles occurred either in chicken embryos or in cultures of embryo kidney cells coinfected with an adenovirus helper. Antigenically the virus was distinct from the adeno-associated viruses types 1, 2, 3, and 4. The virus is the avian equivalent of the adeno-associated viruses of primates and lower animals.  相似文献   
109.
New macromers 4, 8, and 10, containing ester, alcohol, or acid functions, were prepared starting with vinyl chloride (CV) or vinylidene dichloride (CV2). The telomer 1, resulting from CV2 and CCI4 was telomerized with allyl acetate and the product was transformed into the acrylate 4 by hydrolysis of the reaction product and subsequent esterification. Macromers 8 and 10 were prepared from CV by radical telomerization with thioglycolic acid (7) and 2-mercaptoethanol (9), respectively. Reactive double bonds were introduced into these macromers by reaction with acrylic acid, Vinyl chloroformate, methacryloyl chloride, or 2,3 -epoxypropyle methacrylate, leading to new macromers 12, 13, 14, and 15, respectively.  相似文献   
110.
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