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951.
Immunoglobulin E (IgE) was measured in the sera of 18 healthy adult volunteer donors, 67 adults with various types of solid neoplasms, and 17 adults with clinical allergy by means of a double-antibody radioimmunoassay. There was no siginificant difference in the geometric mean serum IgE level between all cancer subjects and the healthy control subjects except that cancer and noncancer patients who had definite clinical allergies showed an increased mean IgE level. Similarly, there was no significant difference in the mean IgE level of any of the six cancer subgroups studied when compared to the control mean. Thus, there was no evidence reflected in serum levels that IgE plays a role in the immunopathology of the cancer population tested. 相似文献
952.
953.
The effect of adrenergic and cholinergic drugs on short incubation “active” E rosette formation was studied in 19 patients with bronchial asthma and 17 healthy controls. Both groups had an equal absolute number of baseline “active” E rosettes, but the asthmatics demonstrated a higher percent baseline value. The beta adrenergic drug isoproterenol (10?3 M) inhibited the formation of “active” E rosettes in asthmatics by only 18.0% as compared to a 60.8% inhibition in the control group. Carbamylcholine (10?5 M) a cholinergic agonist, also showed a lower than normal response in asthmatics, 34.3% enhancement of “active” E rosetting compared to a 52.4% enhancement in the controls. The alpha adrenergic agent phenylephrine (10?5 M) exhibited equal enhancing effects in both groups, 34.2% in the asthmatics and 36.5% in the controls. Isoproterenol (10?3 M) had a minimal effect on inhibition of long incubation “total” E rosettes in both groups studied. The beta adrenergic abnormality conforms to the beta blockade theory of asthma of Szentivanyi. The cholinergic abnormality is unexplained in view of the hyperresponsiveness of patients with asthma to cholinergic agents in vivo. Patients with bronchial asthma probably have an autonomic dysfunction that may play a role in the pathogenesis of their disease. 相似文献
954.
L. K. Archibald O. Nwanyanwu P. N. Kazembe C. Mwansambo M. Bell H. Dobbie L. B. Reller W. R. Jarvis 《Clinical microbiology and infection》2003,9(3):234-238
Children in Malawi receive bacille Calmette-Guérin (BCG) vaccination within the first 3 days of life. Thus, we hypothesized that Malawian children infected with the human immunodeficiency type 1 virus (HIV-1) might be particularly vulnerable to dissemination of the BCG Mycobacterium bovis strain with which they were vaccinated. Following informed consent by parents, we studied children admitted to a Malawi general hospital during the 1998 wet and dry seasons. Blood from cohorts of acutely ill children was cultured for bacteria, including mycobacteria, and fungi, and tested for anti-HIV-1 antibodies. It was shown that non- typhi Salmonella and Escherichia coli were the predominant bloodstream pathogens during the wet and dry seasons, and that bloodstream dissemination of the BCG M. bovis strain is uncommon in HIV-1-infected children who receive the BCG vaccine. 相似文献
955.
JC virus genomes have been localized in formalin-fixed, paraffin-embedded brain tissues of two cases of known progressive multifocal leukoencephalopathy by in situ hybridization utilizing a biotinylated JC virus DNA probe. A three-stage immunoperoxidase system with gold-silver amplification of the diaminobenzidine substrate was used to visualize biotinylated nucleic acid hybrids. Dot-blot quantification of this visualization system indicates that subpicogramme amounts of biotinylated DNA can be detected. Optimal detection of the virus genomes in the brain tissues required a microwave irradiation step prior to hybridization. JC virus genomes were observed in the nuclei of enlarged oligodendrocytes and of some bizarre astrocytes. No other cell types were found to harbour the genomes. 相似文献
956.
Tetsuya Murata Shigeo Nakamura Hiroya Kato Yasushi Yatabe Taizo Shiraishi Makoto Kuroda Ryulchi Yatani Taizan Suchi 《Pathology international》1997,47(11):801-805
A case of Hodgkln's disease (HD), lymphocyte depression (LD) type In an Immunosuppressive patient is described. The patient was a 48-year-old male and his parents were born In the Kyushu area, which is an endemic area for adult T cell lymphomaheukemla (ATL). He was seropositive for ATL virus (ATLV, also referred to as HTLV-I) and showed a marked Immunosuppressive condition. He developed LD-HD and Pneumocystis carinii pneumonia, and died due to respiratory failure. The Immunohistochemical and in situ hybridization analyses revealed that the Reed-Sternberglike cells In the lymph node biopsy sample were positive for Ber-H2 (CD30), Leu-M1 (CD15), L-26 (CD20), Bcl-2, p53 and EBER, the viral genome of Epstein-Barr virus (EBV). 相似文献
957.
Immunogenicity and T cell recognition in swine of foot-and-mouth disease virus polymerase 3D 总被引:1,自引:0,他引:1
Immunization of domestic pigs with a vaccinia virus (VV) recombinant expressing foot-and-mouth disease virus (FMDV) 3D protein conferred partial protection against challenge with infectious virus. The severity reduction of the clinical symptoms developed by the challenged animals occurred in the absence of significant levels of anti-3D circulating antibodies. This observation suggested that the partial protection observed was mediated by the induction of a 3D-specific cellular immune response. To gain information on the T cell recognition of FMDV 3D protein, we conducted in vitro proliferative assays using lymphocytes from outbred pigs experimentally infected with FMDV and 90 overlapping peptides spanning the complete 3D sequence. The use of pools of two to three peptides allowed the identification of T cell epitopes that were efficiently recognized by lymphocytes from at least four of the five animals analyzed. This recognition was heterotypic because anti-peptide responses increased upon reinfection of animals with a FMDV isolate from a different serotype. The results obtained with individual peptides confirmed the antigenicity observed with peptide pools. Detection of cytokine mRNAs by RT-PCR in lymphocytes stimulated in vitro by individual 3D peptides revealed that IFN-gamma mRNA was the most consistently induced, suggesting that the activated T cells belong to the Th 1 subset. These results indicate that 3D protein contains epitopes that can be efficiently recognized by porcine T lymphocytes from different infected animals, both upon primary and secondary (heterotypic) FMDV infection. These epitopes can extend the repertoire of viral T cell epitopes to be included in subunit and synthetic FMD vaccines. 相似文献
958.
乙肝疫苗免疫失败儿童病毒S基因"a"决定簇变异研究 总被引:4,自引:0,他引:4
王永忠 《中国优生与遗传杂志》2003,11(4):29-30
目的 探讨江苏常州地区乙型肝炎疫苗免疫失败儿童病毒S基因“a”决定簇的变异情况。方法 对15例乙肝疫苗接种后血清表面抗原(HBsAg)阳性的儿童,采用聚合酶链反应方法(PCR)扩增其血清中HBV DNA S基因区。并对PCR产物直接标记测序。结果 15例HBsAg阳性儿童有14例血清HBV DNA阳性,其中有4例出现了S基因“a”决定簇的变异,变异率为28.6%,第126位的异亮氨酸(Ile)被苏氨酸(Thr)替代1例,第134位苯丙氨酸(Phe)被异亮氨酸替代1例。第145位甘氨酸(Gly)被丙氨酸(Pha)替代2例。结论乙型肝炎疫苗免疫失败儿童中存在s基因“a”抗原决定簇变异,江苏常州地区存在HBVS基因“a”决定簇变异的新类型。 相似文献
959.
960.
丙型肝炎病毒NS3蛋白单克隆杂交瘤细胞株的建立及初步鉴定 总被引:2,自引:1,他引:2
应用国产基因工程表达的丙型肝炎病毒(HCV)NS3区抗原免疫小鼠,然后取其脾细胞与小鼠骨髓瘤细胞系SP2/0融合,筛选出4株稳定分泌抗HCVNS3区蛋白单克隆抗体(McAb)的杂交瘤细胞株,分别命名为2B6,2F3,3D8,3D9,经初步研究表明这4株单抗与NS3抗原具有良好的反应性,与HCV核心区多肽及乙型肝炎病毒表面抗原和e抗原均无反应。抑制实验表明这4株抗体分别针对NS3抗原分子上的2个不同的抗原决定簇。 相似文献