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61.
Tissue cages implanted subcutaneously were used to infect rabbits with erythrogenic toxin (ET) producing streptococci. The in-vivo production of ET was followed during the infection by immunoprecipitation analyses of the tissue cage fluid (TCF). ET types A and C were mainly detected during the first week of infection, but, as late as 4 weeks after the inoculation, ET was occasionally found in TCF. The nonspecific mitogenic activity of ET on human lymphocytes was also used as a biological marker to recognize ET in TCF. Mitogenic activity was detected in 90% of samples during the first week. In order to characterize the mitogenic material released by growing streptococci, TCF was electrofocused in polyacrylamide gel. The eluates of sliced gels were checked for mitogenic activity and compared with a purified ET preparation containing ET types A and C. It could be verified that ET type A was produced under in-vivo conditions by strains NY-5 and SF130, while ET type C was produced by strain T18. Differences between production of toxins in vitro and in vivo might be of significance for the understanding of the pathogenetic mechanisms in streptococcal infection.  相似文献   
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63.
Summary Hybridoma cell lines grown as ascites tumors in pristane primed mice will frequently yield milligram quantities of monoclonal antibody per milliliter of ascites fluid. Ascites production is an excellent method for the research scientist to generate high titer antibody with minimal effort. Through commercial production, gram to kilogram quantities can be achieved.  相似文献   
64.
By two-colour flow cytometric analysis, we found increased numbers of B cells co-expressing the pan-T cell marker CD5 and the B cell marker CD19 in cerebrospinal fluid (CSF) of 21 patients with multiple sclerosis (MS), compared with 17 control subjects with muscular tension headache. Only one patient with MS, but nine controls lacked CD5+ B cells in CSF. This difference was not observed in peripheral blood. Numbers of CD5+19+ B cells were increased in CSF compared with blood in MS, but not in the controls. In both groups, CD5+19+ B cells were not restricted to small resting lymphocytes, but were also found among larger-sized lymphocytes. The relative density of CD5 molecules and of CD19 molecules was lower in CD5+19+ than in CD5-19+ B cells and CD5+19- T cells. CD5+ B cells are assumed to be responsible for autoantibody production, and our results suggest a pathogenetic role of such cells, predominantly within the central nervous system, in MS.  相似文献   
65.
The last decade has witnessed increasing application of human cytogenetic technology to prenatal chromosome analysis. However, unlike the rather uniform peripheral blood T-lymphocyte system which has provided most of our experience in human cytogenetics, long-term amniotic-fluid cell cultures display extreme cellular heterogeneity and disproportionate growth of certain cell types as a consequence of clonal amplification. When they enter cell culture, many of these cells are approching the terminal stages of their respective life spans and may have accumulated chromosomal aberrations. Concern about the possibility of true fetal mosaicism seems warranted chiefly in situations were multiple colonies display potentially viable aberrations. Clonal analysis, preferable of multiple clonal types, and attention to details of clonal morphology are likely to minimize diagnostic errors and undue apprehension resulting from mosaicism in amniotic-fluid cell cultures.  相似文献   
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Pseudomyxoma peritonei is the clinical term for the diffuse deposition of mucus within the peritoneal cavity secondary to a mucinous tumor of the ovary or appendix. This gelatinous ascites, or "jelly-belly," may result in death from loss of intestinal function and intestinal obstruction caused by peritoneal implants rather than visceral invasion. Microscopic evaluation of peritoneal fluid is frequently an initial diagnostic test; however, in a search of the recent literature we were surprised to find only one case report of the cytologic features. This prompted us to report the cytologic findings in the peritoneal fluid of two cases of pseudomyxoma peritonei arising from appendiceal mucinous cystadenomas.  相似文献   
68.
Anti-IgG; antihodies (anti-IgG) of the IgE class were studied in sera from patients with juvenile rheumatoid arthritis (JRA). rheumatoid arthritis (RA) and patients with Felty's syndrome (FS) by use of an indirect immunofluorescence technique. Forty-two percent of 26 patients with JRA had IgE anti-IgG in serum all in low titers. Positive reactions prevailed in patients with multiple joint involvement. Sixty-three percent of 30 patients with RA and 80% of 20 patients with FS had IgE anti-IgG, the titers found in FS patients being significantly higher. In JRA and FS patients the IgE anti-IgG titers were correlated to the titers of anti-IgG of the IgG class, and for FS patients also with the IgM and IgA classes of anti-IgG. In six of 10 patients with RA the synovial fluid samples from both knees contained IgE anti-IgG. In four of these patients the titers of IgE anti-IgG were higher than in the corresponding serum sample, pointing to a local production. After G-200 Sephadex chromatography IgE anti-IgG were demonstrated in the void volume indicating the presence of these autoantibodies in immune complexes. IgE anti-IgG may be involved in the pathogenesis of JRA and RA by eliciting Type I and III reactions.  相似文献   
69.
A case of primary gastric cancer without hepatic metastasis showing extremely high alpha-fetoprotein (AFP) levels is reported. This case illustrates the application of the immuno-peroxidase technique to ascitic fluid cytology. Papanicolaou-stained smears of the ascites permitted the diagnosis of a metastatic carcinoma. A positive reaction to AFP was demonstrated in the tumor cells in the ascitic fluid cellular samples as well as in the paraffin-embedded tissue section of the primary gastric carcinoma. Rising AFP levels were also detected in ascitic fluid. AFP fractionation using lectin-affinity-crossed-line immunoelectrophoresis showed the hepatic rather than yolk sac type. Reports of such occurrences are few; no study, to the best of our knowledge, has previously documented cytological and immunocytochemical diagnosis in ascitic fluid. AFP-producing gastric cancer should be considered in the differential diagnosis.  相似文献   
70.
Dysfunction of the blood–cerebrospinal fluid barrier (BCB) has been implicated in the pathogenesis of Parkinson's disease (PD) and other neurodegenerative disorders. Therefore, we assayed serum and cerebrospinal fluid (CSF) from 30 parkinsonian patients and 30 controls for concentrations of albumin and IgG. The CSF/serum ratio for albumin (AQ), IgG (GQ), IgG-index as well as determination of oligoclonal bands were used to evaluate BCB function and to quantify humoral immune response within the central nervous system (CNS). Levels of AQ, GQ and IgG-index did not significantly differ in both groups. We found no dysfunction of the blood–CSF barrier or signs of local synthesis of IgG in the central nervous system of parkinsonian patients. Our data do not support the hypothesis of a dysfunctional BCB that contributes to pathophysiological mechanisms underlying PD.  相似文献   
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