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991.
Human polymorphonuclear leukocyte interaction with cyclosporine A.   总被引:4,自引:1,他引:4       下载免费PDF全文
The effects of cyclosporin A (cyA) on human polymorphonuclear leukocyte function, including phagocytosis, its associated metabolic burst, bacterial killing, and chemotaxis, were evaluated. Both Pseudomonas aeruginosa and Staphylococcus aureus were used as test particles. Polymorphonuclear leukocytes incubated in 10 and 50 micrograms of cyA per ml behaved normally with respect to phagocytosis and hexose monophosphate shunt activity at both high (10:1) and low (2:1) S. aureus/leukocyte ratios. With a small bacterial inoculum, killing of S. aureus was slightly impaired at early times only in the presence of 50 micrograms of cyA per ml. Phagocytosis and killing of P. aeruginosa with both large and small bacterial inocula were unaffected by cyA. Chemotaxis was within normal limits under all conditions. In addition, polymorphonuclear leukocytes from four renal transplant recipients receiving both cyA and prednisone demonstrated normal metabolic bursts and bacterial killing with both small and large inocula of S. aureus.  相似文献   
992.
Zusammenfassung Sieben Gruppen von Meerschweinchen zu je 15 Tieren wurden mit virulenten und attenuierten StÄmmen von Poliomyelitis immunisiert und die Antikörperbildung gegen N- und H-Antigen beobachtet. In allen Gruppen wurden zuerst H-Antikörper und spÄter N-Antikörper gebildet. Im weiteren Verlauf der Immunisierung nimmt bei Typ I und Typ II die Bildung von N-Antikörpern wesentlich schneller zu, so da\ die N-Titer bald höher sind als die H-Titer. Gleichzeitig reagieren zuerst mehr Versuchstiere mit H-Antikörper-Bildung, wÄhrend spÄter mehr Tiere N-Antikörper bilden.Bei der Immunisierung mit Typ III reagieren mehr Tiere mit Antikörperbildung gegen H als gegen N, gleichzeitig sind die H-Titer wÄhrend des ganzen Verlaufs höher oder ebenso hoch wie die N-Titer. Die Antikörperbildung gegen die ImpfstÄmme entsprach weitgehend dem Verlauf bei den virulenten StÄmmen. Die Reaktion des Organismus auf die Zufuhr von N- und H-Antigen Ändert sich im Laufe der Immunisierung. Die zu einem spÄteren Zeitpunkt vorgenommenen Booster-Injektionen vermögen das initiale übergewicht der H-Antikörper nicht wiederherzustellen, selbst wenn mehr H- als N-Antigen zugeführt wird.
Antibody production versus poliovirus N and H antigen after immunisation of guinea pigs
Summary Seven groups of guinea pigs consisting of 15 animals each were immunized with virulent and attenuated strains of poliomyelitis virus. Subsequently the antibody production versus N and H antigen was studied. The animals of all groups responded primarily by production of H antibodies and later by N antibodies. During the further course of immunization the production of N antibodies was much faster for type I and II, thus anti N titers soon were higher than anti H titers. In addition, more animals responded initially by production of H antibodies, while later on more animals produce N antibodies. During the immunization with type III more animals produced H than N antibodies and H titers were always higher than N titers or equal. Antibody production to vaccination strains corresponded to a far extent to that of virulent strains. Response of the organism changes during the course of immunization. Booster injections given at a later time do not recall the initial peak of H antibodies, even if a greater dose H antigen is given than N.
  相似文献   
993.
994.
Activity of oxidative enzymes in the epithelium lining the uterine cavity and in the glandular epithelium of ovariectomized rats in the period of climacteric disorders was investigated by a comparative microphotometric method. An increase in lactate dehydrogenase (LD) and glucose-6-phosphate dehydrogenase (G6PD) activity and a decrease in succinate dehydrogenase (SD) and NAD- and NADP-diaphorase activity were found in the epithelial cells lining the uterine cavity. LD activity was increased in the glandular epithelium but SD, and NAD- and NADP-diaphorase activity was sharply reduced. Injection of testosterone propionate caused a marked increase in the activity of the oxidative enzymes studied in the endometrial epithelium of the rats compared with their activity in control rats and in rats not receiving the hormone.Research Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. Department of Obstetrics and Gynecology, Daghestan Medical Institute, Makhachkala. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 209–212, February, 1978.  相似文献   
995.
Chinese hamster ovary cells harbour intracytoplasmic virus-like particles of type A which are closely associated with sites of microtubule formation. We report here the enhanced proliferation of these particles and their release at the cell membrane by using either 5-bromodeoxyuridine or dibutyryl cyclic AMP. The extracellular mature particles are similar in morphology to retroviruses of type B. Close association of the type A virus precursors with microtubule organizing centres, i.e. kinetochores, centrioles and basal bodies, and with microtubules per se, is confirmed by studying the effects of the microtubule inhibitors Colcemid and vincristine sulphate. The role of microtubules in the activation and transport of the intracytoplasmic type A particles is discussed.  相似文献   
996.
The aim of this study was to determine the expression levels of p53 and TATA binding protein (TBP) and the presence of autoantibodies to these antigens in Asian Indian patients with systemic sclerosis (SSc), overlap syndromes (OS) and systemic lupus erythematosus (SLE). Fifty patients with SSc, 20 with OS, including mixed connective tissue diseases (MCTD), 20 with SLE, 10 disease controls (DC) and 25 controls (C) were studied. The over-expression of p53 and TBP antigen was determined quantitatively by sandwich enzyme-linked immunosorbent assay (ELISA), varies between four- and sevenfold higher in patients with SSc, OS and SLE, in comparison to DC and C. The expressed protein antigens were not present as free antigens but as immune-complexes. Autoantibodies to p53 were detected by ELISA in 78% subjects with SSc, 100% with OS and 80% with SLE. Autoantibodies to TBP were observed in 28% patients with SSc, 25% with OS and 15% with SLE. In comparison to healthy controls, the titre of antibodies to p53 was significantly higher in patients with SSc (P = 0.00001) than the patients with OS (P = 0.00279) and SLE (P = 0.00289), whereas the titre of antibodies to TBP was higher in patients with OS (P = 0.00185) than the SLE (P = 0.00673) and the SSc (P = 0.00986) patients. Autoantibodies to p53 and TBP were detected in all these patients and the levels of these two autoantibodies showed weak negative correlation with each other. We propose that the over-expression of these antigens might be due to hyperactive regulatory regions in the p53 and TBP gene.  相似文献   
997.
We have studied 4 patients with inverted tandem duplications of parts of chromosomes, a hitherto rarely identified form of a structural rearrangement involving a single chromosome in man. In patients 1 and 2, the duplication involved parts of the short arm of chromosome 8 (regions 8p12 leads to 8p23 and 8p21 leads to 8p23, respectively). Both patients manifested certain characteristics of the mosaic trisomy 8 syndrome. Elevated levels of glutathione reductase (GSR) in their erythrocytes supported the interpretation of a partial duplication of chromosome 8 and indicated a regional localization for the GSR gene locus. In Partient 3, the distal half of the long arm of chromosome 4 was duplicated (region 4q23 leads to 4q35). Clinical evidence supported this interpretation, as Patient 3 resembled phenotypically the 13 reported cases with duplication of the distal 4q. The cytogenetic findings in Patient 4 suggested a possibly inverted duplication of 22q. The clinical correlation was less convincing due to the lack of a well-defined phenotype for trisomy 22. These chromosome aberrations had occurred de novo in all 4 cases. Although they involved different chromosomal regions, they might well have arisen by the same mechanism. Possible modes of origin that are discussed in detail include unequal exchange between homologous chromosomes, between chromatids of 1 chromosome or between strands of 1 DNA duplex.  相似文献   
998.
The kinetics of appearance of MIF+ cells was investigated in experimental contact dermatitis using a monoclonal antibody (7D10) against murine MIF which was reacted with cryostat sections of tissues and detected by the indirect immunoperoxidase test. Four groups of BALB/c mice were investigated: (1) sensitized with 2,4-dinitrofluorobenzene (DNFB); (2) unsensitized controls; (3) tolerized; (4) unsensitized. A challenge dose of DNFB was applied to the ear of animals of groups 1-3 and of croton oil to those of group 4. Three phases could be distinguished in group 1: (a) an initial vascular and exudative reaction; (b) an early cellular phase; and (c) a late cellular phase. At zero time rarely any T lymphocytes (Lyt 1+; Lyt 2+) were seen in all four groups. Within less than 30 min venous endothelial cells became strongly MIF+. This was followed by an influx of monocytes/macrophages reaching a maximum of 72 h in group 1 and a slight peak at 12 h in groups 2 and 3. At 16-24 h in all groups the endothelial reaction weakened while many 7D10+ macrophages appeared in group 1. By double-labelling it was shown that lymphocytes were 7D10-. The influx of lymphocytes, part of which carried the T cell receptor, began at 12 h, reaching a maximum at 72 h in group 1. In groups 2 and 3 only a weak lymphocytic infiltrate developed which declined at 24 h. Group 4 developed an inflammatory reaction after the initial phase with similar kinetics as in group 1. The data suggest that an immune inflammatory reaction is preceded by a nonspecific reaction of the vascular endothelium and the mononuclear phagocytic system and that MIF is playing a central role in these events.  相似文献   
999.
The major cause of mortality in human schistosomiasis is the chronic granulomatous reaction of the liver tissue to Schistosoma mansoni eggs. Liver biopsy still provides the best evaluation of the degree of liver damage. However, liver biopsy does not provide an image of the dynamic process of fibrogenesis. Variations of concentrations of procollagen type III peptide in sera have been proposed to be significant markers of liver fibrosis. Thus, liver function tests in relation to histopathological diagnosis and procollagen type III peptide concentrations were studied in patients with schistosomiasis and revealed a high correlation between the serum procollagen type III peptide and the degree of fibrosis in liver tissue.  相似文献   
1000.
Three systems for the identification of nonfermentative bacilli were evaluated for their rapidity and accuracy of identification of 217 strains. Two of the systems, API 20E (API) and Oxi/Ferm tube (OxiF), are available as kits; the oxidative attack (OA) system is not commerically available. The overall accuracies of the OA, API, and OxiF systems were 91, 69, and 50%, respectively. Identification within 48 h was achieved for 98% of the strains by OA, for 50% by API, and for 18% by OxiF. Most of the organisms that were either misidentified or not identified by API and OxiF were those nonfermentative bacilli which are relatively more fastidious or rarely encountered or both. All three systems accurately identified nonfermentative bacilli commonly isolated at Olive View Medical Center, namely, Pseudomonas aeruginosa, Acinetobacter anitratus, Pseudomonas maltophilia, Acinetobacter lwoffi, saccharolytic flavobacteria (CDC IIb), moraxellae, Pseudomonas fluorescens, and Pseudomonas putida. The OA system identified 100% of the above organisms correctly, API identified 99.4%, and OxiF identified 99.3%. Since these organisms comprise 92% of the total number of nonfermentative bacilli isolated at Olive View Medical Center, we conclude that both API and OxiF may be useful alternatives to conventional methods, based on accuracy of identification alone. These two systems were considered substantially inferior to the OA system when both accuracy and rapidity of identification were taken into account.  相似文献   
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