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21.
Numbers of splenic antibody-producing cells and humoral antibody titres were elevated during immunization regimes in rainbow trout when the bacterins Yersinia ruckeri or Aeromonas salmonicida O-antigen preparations were mixed with the immunostimulator FK-565. Fish sampled 14 days after injection showed a marked increase in the immune response when doses of 5, 10 or 100 μg of antigen were used. The immunostimulator may aid initial antigen uptake and processing.  相似文献   
22.
When a murine leukemia L1210-specific Lyt-2+ T cell clone, K7L, was injected i.p. into CD2F1 mice together with L1210, the normal growth of L1210 in the peritoneal cavity of the mice at the early stage (days 0 to 5) was strongly inhibited, but L1210 grew progressively at the middle-stage (days 5 to 10), and then was rejected at the late stage (days 10 to 20). The mice thus survived for long times (more than 60 days), whereas the normal control injected with L1210 alone died within 14 days. The L1210 that grew at the middle stage in mice initially inoculated with L1210 together with K7L was a K7L-insensitive (K7L-) variant. All of eight tumor clones established from L1210-K7L- by limiting dilution was insensitive to the antitumor activity of K7L, and this property of tumor clones was stable after repeated in vitro passage. The initial depression of the L1210 growth by K7L followed by growth and rejection of the variant L1210-K7L- by the host T cell activity was then found to prepare a strong, long-lasting (more than 3 mo) immunity to protect mice against the high-dose (10(7) cells per mouse) challenge of original L1210. Corresponding to this result, definite tumor (L1210)-specific cytotoxic T lymphocyte (CTL) activity against both variant and original L1210 targets was developed by antigen (L1210) restimulation in the culture of spleen cells from these mice, but was not increased to a detectable level before L1210-K7L- variant started to grow. It was suggested that the 1210-K7L- variant and the original L1210 should have the common tumor-specific antigen that was independent of the K7L-reactive antigen, and that original L1210, whose growth was retarded by K7L, primed the host with the common antigen to be enormously boosted by the subsequently growing L1210-K7L- variant.  相似文献   
23.
Mitochondrial dysfunction in ischemic liver has been demonstrated to be due to decrease in the intramitochondrial level of ATP and the subsequent disruption of the proton barrier of the inner membrane (Watanabe, F., Hashimoto, T. and Tagawa, K. (1985) J. Biochem. 97, 1229-1234). In this study, another injury process, impairment of the electron-transfer system, which occurred during reoxygenation of ischemic liver, was studied during reperfusion of cold preserved liver and during cold incubation of isolated rat-liver mitochondria. The sites of the respiratory chain that were sensitive to peroxidative damage were ubiquinone-cytochrome c oxidoreductase and NADH-ubiquinone oxidoreductase. These enzymic activities decreased with increase in lipid peroxidation. Incubation of submitochondrial particles with t-butyl hydroperoxide or with an NADPH-dependent peroxidation system decreased the enzymic activities of the electron-transport system. These data strongly suggested that lipid peroxidation during reoxygenation of ischemic liver impaired the electron-transfer system. Thus, mitochondria of ischemic liver suffer from two different types of injury: increase in proton permeability during anoxia, and decrease in enzymic activities of the electron-transport system during reoxygenation.  相似文献   
24.
The generic names of the brown algaeMyagropsis, Cystoseira andCystophyllum have been used in Japan, Korea and China for a small group of seaweeds whose limits have not been clearly understood. Studies on the development of the eggs and subsequent germlings show that substantial differences occur betweenCystoseira andMyagropsis. Myagropsis Kützing is distinguished fromCystoseira C. Agardh by the following characteristics: (1) the tongue cell is undivided during development of the conceptacle; (2) paraphyses are projected from the conceptacle ostiole and become entangled; (3) during development, oospore germlings are mixed among paraphyses projecting from the ostiole; (4) oospores are large, with eight nuclei at maturity; (5) thirty-two primary rhizoids are produced on the germlings; and (6) the thallus is bilateral in organization. The shape and size of vesicles, their formation, and the presence of cryptostomata have been used as specific characters, but their use cannot be continued. It is concluded that the genusMyagropsis is monotypic, with a single species,M. myagroides (Turner) Fensholt. The status of this species is also discussed.  相似文献   
25.
To elucidate the physiological significance of ketone bodies on insulin and glucagon secretion, the direct effects of beta-hydroxybutyrate (BOHB) and acetoacetate (AcAc) infusion on insulin and glucagon release from perfused rat pancreas were investigated. The BOHB or AcAc was administered at concentrations of 10, 1, or 0.1 mM for 30 min at 4.0 ml/min. High-concentration infusions of BOHB and AcAc (10 mM) produced significant increases in insulin release in the presence of 4.4 mM glucose, but low-concentration infusions of BOHB and AcAc (1 and 0.1 mM) caused no significant changes in insulin secretion from perfused rat pancreas. BOHB (10, 1, and 0.1 mM) and AcAc (10 and 1 mM) infusion significantly inhibited glucagon secretion from perfused rat pancreas. These results suggest that physiological concentrations of ketone bodies have no direct effect on insulin release but have a direct inhibitory effect on glucagon secretion from perfused rat pancreas.  相似文献   
26.
Using site-directed mutagenesis, Glu-190 or Glu-201 of the beta subunit of the F1-ATPase from the thermophilic bacterium PS3 were replaced with glutamine. It was possible to reconstitute complexes of the mutated beta subunits with alpha and gamma subunits, but the complexes did not have ATPase activity. It is concluded that carboxylic acid side chains of Glu-190 and Glu-201 of the beta subunit are essential for catalytic activity of F1-ATPase.  相似文献   
27.
A human-mouse hybrid segregant HM76Dd40-6 with new characteristics was derived from the hybrid cell line HM76Dd containing human chromosome 19 as the only human chromosome. Three virus sensitivities located on human chromosome 19 (PVS, E11S and RDRC) were lost in HM76Dd40-6, while six other genes (C3, LDLR, EF2, GPI, PEPD and MANB) were retained. Cytogenetic analysis and in situ hybridization using human or mouse repeated sequences as probes showed that the region q13.1-qter of human chromosome 19 had been replaced by a fragment of mouse chromosome. Our results permit further regional assignment for the following five genes on human chromosome 19: GPI in the region cen-q12, MANB in p13.2-q12, E11S and RDRC in q13.1-qter, and EF2 in pter-q12.  相似文献   
28.
Azopigments were obtained from the delta fraction of bilirubin (mammalian biliprotein) in cholestatic sera of men, rats and guinea pigs by diazo reaction with diazotized p-iodoaniline and analysed by t.l.c. Delta bilirubin of men and rats generated both unconjugated and glucuronide-conjugated azodipyrroles, whereas that of guinea pigs, in which the predominant form of conjugated bilirubin in serum was bilirubin monoglucuronide, generated only unconjugated azodipyrrole. We further analysed the azopigments by reversed-phase h.p.l.c. to distinguish their endovinyl and exovinyl isomers. The results indicated (a) that covalent binding of bilirubin to protein occurs exclusively on the conjugated dipyrrolic (either endovinyl or exovinyl) half of the parent conjugated bilirubin, (b) that both bilirubin monoglucuronide and bilirubin diglucuronide generate delta bilirubin, the latter yielding a 'conjugated' form of delta bilirubin that preserves the glucuronic acid moiety on the dipyrrolic half not bound covalently to protein, and (c) that therefore at least four forms of delta bilirubin exist in jaundiced sera of men and rats.  相似文献   
29.
Dermatan sulfate proteoglycan chains were detected in tissue sections treated with chondroitin B-lyase (0.01 units/ml) in 20 mM Tris-HCl (pH 8.0) for 1 hr, followed by staining with antibody 9A2 specific for unsaturated uronic acid coupled to N-acetylgalactosamine-4 sulfate. In contrast, after treatment with chondroitin B-lyase, no positive staining was observed with antibodies 3B3 and 1B5 which react to the unsaturated uronic acid coupled to N-acetylgalactosamine 6-sulfate and unsaturated uronic acid coupled to N-acetylgalactosamine, respectively. The distribution of dermatan sulfate thus revealed was confirmed by comparison with that found by monoclonal antibody 6B6 which reacts with small proteoglycans carrying dermatan sulfate side chains. The localization of positive staining in fibrous connective tissues was almost identical with these two procedures.  相似文献   
30.
Two kinds of low molecular weight kininogen (termed LK1 and LK2) were isolated from pooled plasma of guinea pigs. When polyclonal antisera raised against the individual proteins were used, immunological cross-reactions were observed between LK1 and high molecular weight kininogen (HK), but not either between LK1 and LK2 or between LK2 and HK. After tissue injury, plasma level of LK1 doubled while those of LK2 and HK remained relatively unchanged.  相似文献   
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