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51.
52.
Mice undergoing graft-versus-host reaction, skin grafting, and inoculation with tumor cells were tested for nonspecific resistance by intravenous challenge with Listeria monocytogenes. Peritoneal exudate macrophages from mice treated in a similar manner were tested in vitro for increased degradation of [1-14C]glucose, ability to degrade antigen/antibody complexes, ability to inhibit intracellular growth of listeria, and staining for beta-galactosidase. There was good correlation between in vivo resistance towards L. monocytogenes and in vitro inhibition of intracellular growth. There was also good correlation between increase in beta-galactosidase and in vivo resistance in mice undergoing a graft-versus-host-reaction. 相似文献
53.
Identification of thorium dioxide in human liver cells by electron microscopic x-ray microanalysis. 下载免费PDF全文
Thirty-two years after injection of thorium dioxide (Thorotrast) for diagnostic x-ray studies in a female patient deposits were found by light microscopy in the liver macrophages (Kupffer cells). They were shown by electron microscopy to be located inside secondary lysosomes, and by autoradiography and x-ray microanalysis they were identified as thorium. 相似文献
54.
HLA/Bf haplotypes were examined in a large three-generation Newfoundland family with a high incidence of Graves' disease. In that family Graves' disease was inherited in association with the haplotype HLA Aw24, Bw39 in some instances and with HLA B8-containing haplotypes in other instances. As all seven members of the family who suffered from Graves' disease were homozygous for the Bf S allele, the study for Bf was uninformative. However, the examination of other HLA/Bf haplotypes disclosed some interesting associations. One-hundred-and-five out of 168 HLA-A, -B, -Bf haplotypes were Bf S. Although numerically deviant, no unusual HLA B/Bf associations were observed. Bf F entered the family only once. A new finding is the association between HLA B27 and Bf S1; the haplotype entered the family once and was passed on to eight family members over three generations. Bf S1 was previously reported in association with HLA B12 or W21. None of these family members had ankylosing spondylitis. The Bf allele F1 entered the family three times, always in association with HLA B18. 相似文献
55.
Lectin characterization of gonococci from an outbreak caused by penicillin-resistant Neisseria gonorrhoeae. 总被引:1,自引:0,他引:1 下载免费PDF全文
W O Schalla R J Rice J W Biddle Y Jeanlouis S A Larsen W L Whittington 《Journal of clinical microbiology》1985,22(4):481-483
A total of 40 Neisseria gonorrhoeae isolates, representing 19 penicillin-resistant isolates (from 8 heterosexual patients and 11 homosexual patients) and 21 penicillin-susceptible isolates (from 15 heterosexual patients and 6 homosexual patients) and obtained from the same geographic area, were examined. Lectin agglutination patterns were based on the reactivity of the isolates with the following 14 lectins: concanavalin A, Lens culinaris, Trichosanthes kinlowii, Griffonia simplicifolia I, Arachis hypogeae (peanut agglutinin), Glycine max (soybean agglutinin), Dolichos bifloris, Griffonia simplicifolia II, Solanum tuberosum (potato starch agglutinin), Triticum vulgaris (wheat germ agglutinin), Limax flavus, Phaseolus vulgaris, Ulex europaeus I, and Lotus tetragonolobus. All isolates were serotyped with monoclonal antibodies specific for gonococcal outer membrane protein I and auxotyped, and the plasmid content was determined. Resistant patient isolates were selected for their decreased penicillin susceptibility, and control isolates were selected for their penicillin susceptibility. Even though the patient isolates demonstrated resistance to penicillin, no phenotypic differences in lectin-grouping patterns were demonstrated between the two study groups; i.e., two predominant lectin groups were observed. No resistance-associated plasmids were detected. All patient isolates were serogroup IB (serovars IB-1, IB-2, and IB-4), whereas 12 of 21 control isolates were serogroup IA (P less than 0.05). Isolates obtained from different anatomical sites in the same patient (cervical and rectal) agreed with regard to lectin patterns and serovars but not auxotypes. 相似文献
56.
Increased Sensitivity of a New Coagglutination Test for Rapid Identification of Haemophilus influenzae Type b 下载免费PDF全文
Robert J. Grasso Loyd A. West Nikki J. Holbrook Demetrios G. Halkias Lois J. Paradise Herman Friedman 《Journal of clinical microbiology》1981,13(6):1122-1124
A newly developed rapid coagglutination test for identifying Haemophilus influenzae type b organisms isolated from clinical specimens correlated 100% with the slide agglutination test but was 100- to 200-fold more sensitive. 相似文献
57.
Retinoblastoma and p53 gene product expression in breast carcinoma: Immunohistochemical analysis and clinicopathologic correlation 总被引:9,自引:0,他引:9
Michel Trudel MD Lois Mulligan PhD Webster Cavenee PhD Richard Margolese MD Jean Ct MD Gilles Garipy MD 《Human pathology》1992,23(12):1388-1394
We examined 100 breast cancers for retinoblastoma (Rb) and p53 protein expression by immunohistochemistry using the PMG3.245 and PAb 1801 antibodies. We assessed percentages of reactive cells and their intensity, as well as staining patterns. The results were correlated with neu protein reactivity and a panel of variables, including age, tumor size and type, nuclear grade, estrogen receptor/progesterone receptor content, and lymph node status. Retinoblastoma protein negativity, either partial or complete, was noted in 47% of cases. Surprisingly, a relatively stronger Rb reaction was seen in some high nuclear grade tumors. p53 positivity was found in 23% of cases and was a significant predictor of Rb loss. p53 also was correlated with poorly differentiated (nuclear grade III) neoplasms and neu expression but not with negative ER status. Tissue distribution profiles for Rb-negative and p53-positive cells were variable in this series, with both uniform and heterogeneous patterns observed. This suggests that Rb and p53 alterations may represent early or late events in transformation. Our findings further implicate Rb and p53 derangements in mammary oncogenesis. 相似文献
58.
Frequency of Cytotoxic T Lymphocyte Precursors to Herpes Simplex Virus Type 1 as Determined by Limiting Dilution Analysis 总被引:4,自引:0,他引:4 下载免费PDF全文
The conditions for establishing a limiting dilution assay to measure cytotoxic T lymphocyte precursors (CTL-P) against herpes simplex virus type 1 (HSV-1) were determined. Analysis by Poisson statistics demonstrated that the estimated frequency of HSV-1-reactive cells in the spleens of normal mice was less than 1/250,000. In contrast, mice immunized previously with infectious HSV-1 demonstrated a CTL-P frequency between 1/3,500 and 1/15,670. The generation of a maximum cytotoxic T lymphocyte response required that mice be primed in vivo with infectious virus. Immunization with inactivated virus either failed to elicit detectable CTL-P frequencies or gave frequencies markedly less than those induced with infectious virus. To obtain positive cultures, the responder cell population had to be exposed to stimulator splenocytes expressing viral antigens. Normal splenocytes without virus or normal splenocytes with T cell growth factor did not result in significant cytotoxicity. Split culture analysis comparing cytotoxicity against syngeneic and allogeneic virus-infected targets provided evidence for specificity, H-2 restriction, and the T cell nature of the CTL-P. It was determined that precursors were eliminated by treatment with anti-Thy 1, Lyt 2.1, or Lyt 1.1, indicating the CTL-P were Lyt 1(+)2(+) cells. Cytotoxicity was reduced after treatment of the responders with anti-Lyt 2 plus complement, which gave further evidence of the T cell nature of the cytotoxic T lymphocytes. These experiments demonstrated the feasibility of using the limiting dilution approach as a highly sensitive and quantitative means to measure the cell-mediated immune response to HSV-1 antigens. 相似文献
59.
A differential effect of C5a and C5a des Arg in the induction of pulmonary inflammation. 总被引:10,自引:8,他引:10 下载免费PDF全文
G. L. Larsen K. McCarthy R. O. Webster J. Henson P. M. Henson 《The American journal of pathology》1980,100(1):179-192
Earlier studies have shown that C5 fragments induce an inflammatory reaction when instilled into the rabbit lung. Because C5a is rapidly converted to C5a des Arg in vivo, experiments were performed to determine which fragment was most effective in producing pulmonary inflammation in this animal model. C5a des Arg consistently produced marked inflammation. This was characterized by neutrophil accumulation, edema, hemorrhage, fibrin formation, and damage to alveolar epithelium. The time course of the inflammatory reaction initiated by C5a des Arg showed pulmonary vascular sequestration of neutrophils with no intra-alveolar migration at 30 minutes after injection. By 2 hours, interstitial and alveolar neutrophils were numerous, with the accumulation of neutrophils in the alveoli increasing to a maximum at 6 hours. At 24 and 48 hours, the predominant cells were mononuclear (macrophages). By 120 hours, the lesions were resolving. In contrast, at all doses examined, a similar instillation of C5a induced either no inflammation or a milder, more focal response than C5a des Arg. This inability of C5a to initiate inflammation was not apparently due to the generation of inhibitors, since mixtures of C5a and C5a des Arg were phlogistic. A prolonged, intrapulmonary infusion of C5a (20 minutes), in contrast to a bolus instillation (1 minute), did initiate an inflammatory response, which may reflect the conversion of the C5a to C5a des Arg in the lung. This study points out the inflammatory potential of products of complement activation, particularly of the C5 fragment C5a des Arg, when applied to the airway side of the lungs. This inflammatory response raises the possibility that cleavage of intrapulmonary C5 may play an important role in the initiation of pulmonary inflammation. 相似文献
60.
One hundred twenty-two patients with various colon pathologies (43 colorectal carcinoma patients exclusive of the known autosomal dominant colorectal cancer syndromes, 31 patients with solitary colorectal adenomas, 27 patients with ulcerative colitis, and 21 controls with no evidence of colorectal cancer) were investigated for in vitro tetraploidy in dermal fibroblasts cultures using a metaphase assay for determination of numerical chromosomal alterations. Later, stationary cultures of these skin fibroblasts were investigated with DNA flow cytometry. There was good correlation between the percentage of tetraploid metaphase cells and the percentage of nuclei with a flow cytometric DNA index of 2. Using a linear discrimination function to classify the flow cytometric data, the peak with DNA index of 2 was the most important parameter, supplemented by the region with DNA index greater than 2, whereas the region with DNA index between 1 and 2 probably represented a different subpopulation. We have thus demonstrated that only the region with a DNA index of 2 or greater is suitable in determining in vitro tetraploidy in stationary skin fibroblast cultures. 相似文献