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111.
Passive immunization of mice with monoclonal antibodies to glycoprotein gB of herpes simplex virus 总被引:2,自引:0,他引:2
To investigate the protective ability of monoclonal antibodies (MCAs) to viral glycoprotein in herpes simplex virus (HSV) infection, athymic nude mice were inoculated intracutaneously with HSV type-1 (HSV-1) in the midflank. Three hours after inoculation, one group of mice was passively immunized with one of a series of MCAs to glycoprotein gB of HSV-1, and a control group of mice was given phosphate buffered saline alone. The control mice died within 16 days after infection, whereas the mice passively immunized with any of the MCA showed suppressed development of skin lesions. Three of six mice given MCA failed to develop any visible lesions and no HSV could be isolated from the lumbar dorsal root ganglia of these mice 60 days after the challenge. BALB/c mice were also protected from infection with HSV type 2 by passive immunization with MCA to HSV-1 gB. 相似文献
112.
D aft , M.J., B urnham , J.C. & Y amamoto , Y. 1985. Lysis of Phormidium luridum by Myxococcus fulvus in continuous flow cultures. Journal of Applied Bacteriology 59 , 73–80.
In two chemostat systems Myxococcus fulvus (strain BGO2) adhered to the glass walls of the growth vessel and on glass beads contained in a vertical glass column. The bacterium produced long colonial strands that extended towards the centre of the vessel. Both systems allowed measurement of lytic enzyme production and cyanobacterial predatory efficiency. Lysozyme activity produced by the myxococci was dependent on the concentration of the tryptone and the flow rate of the medium. Continuous lysis of Phormidium luridum occurred in both methods of culture in the presence of M. fulvus (strain BGO2). The results suggest that the adhesive characteristics of this bacterium prevent the achievement of steady state kinetics in either saprophytic or parasitic modes of growth. M. fulvus , with its various morphological growth forms and effectiveness in lysing cyanobacteria, is considered to be a potential control agent of cyanobacteria. 相似文献
In two chemostat systems Myxococcus fulvus (strain BGO2) adhered to the glass walls of the growth vessel and on glass beads contained in a vertical glass column. The bacterium produced long colonial strands that extended towards the centre of the vessel. Both systems allowed measurement of lytic enzyme production and cyanobacterial predatory efficiency. Lysozyme activity produced by the myxococci was dependent on the concentration of the tryptone and the flow rate of the medium. Continuous lysis of Phormidium luridum occurred in both methods of culture in the presence of M. fulvus (strain BGO2). The results suggest that the adhesive characteristics of this bacterium prevent the achievement of steady state kinetics in either saprophytic or parasitic modes of growth. M. fulvus , with its various morphological growth forms and effectiveness in lysing cyanobacteria, is considered to be a potential control agent of cyanobacteria. 相似文献
113.
114.
Yamamoto H.; Inaba S.; Nishiura Y.; Kishi F.; Kawakami Y. 《Journal of applied physiology》1985,58(3):717-723
Hypoxic and hypercapnic ventilatory responses were measured after two levels of acute inhalation of cigarette smoke, minimum-level nicotine smoke (smoke 1) and nicotine-containing smoke (smoke 2), in 10 normal men. Chemosensitivity to hypoxia and hypercapnia was assessed both in terms of slope factors for ventilation-alveolar PO2 curve (A) and ventilation-alveolar PCO2 line (S) and of absolute levels of minute ventilation (VE) at hypoxia or hypercapnia. Ventilatory response to hypoxia and absolute level of VE at hypoxia significantly increased from 23.5 +/- 22.6 (SD) to 38.6 +/- 31.3 l . min-1 . Torr and from 10.6 +/- 2.5 to 12.6 +/- 3.5 l . min-1, respectively, during inhalation of cigarette smoke 2 (P less than 0.05). Inhalation of cigarette smoke 2 tended to increase the ventilatory response to hypercapnia, and the absolute level of VE at hypercapnia rose from 1.42 +/- 0.75 to 1.65 +/- 0.58 l . min-1 . Torr-1 and from 23.7 +/- 4.9 to 25.5 +/- 5.9 l . min-1, respectively, but these changes did not attain significant levels. Cigarette smoke 2 inhalation induced an increase in heart rate from 64.7 +/- 5.7 to 66.4 +/- 6.3 beats . min-1 (P less than 0.05) during room air breathing, whereas resting ventilation and specific airway conductance did not change significantly. On the other hand, acute inhalation of cigarette smoke 1 changed none of these variables. These results indicate that hypoxic chemosensitivity is augmented after cigarette smoke and that nicotine is presumed to act on peripheral chemoreceptors. 相似文献
115.
In vitro characteristics of rat mesangial cells in comparison with aortic smooth muscle cells and dermal fibroblasts 总被引:2,自引:0,他引:2
E Yaoita T Kazama K Kawasaki S Miyazaki T Yamamoto I Kihara 《Virchows Archiv. B, Cell pathology including molecular pathology》1985,49(4):285-294
Rat glomerular mesangial cells were cultured and their antigens were compared with those of aortic vascular smooth muscle cells and dermal fibroblasts. Glomeruli, aortic, and dermal explants were cultured for 3 weeks and subcultured in the same conditions. These cultured cells were evaluated by indirect immunofluorescence studies using antibodies against Thy-1 antigen, desmin, and chicken gizzard actin. Most of mesangial cells were positive for Thy-1, desmin, and actin. On the other hand, fibroblasts were negative for desmin, and smooth muscle cells stained Thy-1 scarcely, and were negative for desmin. In the latter two cells, actin-positive fibrils were thinner and fainter than mesangial cells. These results indicated that mesangial cells could be distinguished in vitro from vascular smooth cells and fibroblasts by immunofluorescence microscopy. 相似文献
116.
An acid phosphatase species which is activated by Fe2+ was purified 3,700-fold from rat spleen by chromatography on columns containing Blue-Sepharose, concanavalin A-Sepharose, Sephadex G-100, and CM-Sephadex. The enzyme hydrolyzed aryl phosphates, nucleoside di- and triphosphates, phosphoproteins, and thiamine pyrophosphate with Km values of 10(-4) to 10(-3) M at an optimal pH of 5.0-5.8. Co-purification of the acid phosphatase and acid phosphoprotein phosphatase indicated that they were identical. The purified enzyme was glycoprotein in nature, showing four heterogeneous forms on acid polyacrylamide gel electrophoresis (pI values, 7.8, 8.0, 8.3, and 8.5), but it gave a molecular weight of 33,000 on sodium dodecyl sulfate-gel electrophoresis and gel permeation chromatography. The enzyme had a purple color (lambda max 545 nm) and contained 2 iron atoms per enzyme molecule. Among reductants, ascorbic acid and Fe2+ were the best activators, although their combined effect was not additive. Fe2+ and ascorbic acid both changed the purple enzyme into the same active form (lambda max 515 nm), giving almost the same kinetic constants for substrates and for inhibitors such as molybdate, phosphate and fluoride. However, low concentrations of Fe2+, from 0.01 mM to 1.0 mM, immediately and reversibly activated the enzyme, whereas high concentrations of ascorbic acid over 1 mM were required for maximal activation, which was slow and irreversible. 相似文献
117.
A Ca2+, calmodulin-dependent protein kinase from rat brain with a MW of 640,000 phosphorylated calmodulin-sensitive phosphodiesterase from the brain cytosol. The Km of the enzyme for the phosphodiesterase was 5.0 microM and the Vmax was 212 nmol/mg/min. The amount of phosphate incorporated into the phosphodiesterase was 0.7 mol/mol subunit. Phosphorylation of the phosphodiesterase enhanced the enzyme activity by about 20% for hydrolysis of a higher concentration of cyclic AMP. 相似文献
118.
T. Yamamoto A. Motegi T. Takei H. Okayama T. Sawai 《Molecular & general genetics : MGG》1984,193(2):255-262
Summary We report that plasmid R46 provides a function which promotes recA-independent deletion, replicon fusion, and resolution of the fusion. R46 belongs to the incompatibility group N and specifies resistance to ampicillin, tetracycline, streptomycin and sulfonamide. Four kinds of deletion derivatives were observed by selection for susceptability to tetracycline from ampicillin-resistant clones. A common region, will be called region thereafter, was postulated to be involved in these deletions. The replicon fusion occurred by a conjugative mobilization of each derivative with plasmid R388. The fusion was suggested to contain both replicons linked at each junction by the sequence in the region in direct orientation. The resolution of the replicon fusion was found between two regions and a consequently generated, parental deletion derivative and an R388 derivative which gained one region. It is possible that the region contains one potential Insertion Sequence (IS) element. These events were also speculated to occur as a consequence of insertion of the potential IS onto the intramolecular or intermolecular target sequence, or reciprocal recombination between two potential IS elements. 相似文献
119.
N Kobayashi Y Koyanagi N Yamamoto Y Hinuma H Sato K Okochi M Hatanaka 《The Journal of biological chemistry》1984,259(18):11162-11164
Human T-cell leukemia virus producer cell line MT-2 was labeled with [32P]phosphoric acid, and its cell extracts were immunoprecipitated with mouse monoclonal antibodies (GIN-7, and KK-1) and rabbit sera (anti-p24, and anti-gp68). Analysis of the immunocomplexes on sodium dodecyl sulfate-polyacrylamide gell electrophoresis revealed that p53, p28, and p19 of adult T-cell leukemia-associated antigens were phosphorylated in vivo. Immunocomplexes of MT-2 cell extract with monoclonal antibody KK-1 were incubated with [gamma-32P]ATP in vitro and it was revealed that the phosphokinase activity was associated with p28. The phosphokinase activity of p28 was specific to the serine residue but was not to the tyrosine residue. 相似文献
120.
Ken-ichi Yamamoto Osamu Hirano Yoichi Hara Hiroshi Yoshikawa 《Ichthyological Research》1987,33(4):399-404
A cyprinid fish,Pseudogobio esocinus showed gradual bradycardia at oxygen saturation (%) of less than 29.7±4.6 (1.89±0.29 ml/l of oxygen concentration), surfacing at 14.7±1.3 (0.94±0.09ml/l), drastic decrease of oxygen consumption at less than 14.2±0.8 (0.91 ±0.06ml/l) and asphyxia at 9.7±1.4 (0.62±0.09ml/l). The fish avoided water having low oxygen saturation of less than 54.0± 5.4 (3.38±0.30ml/l), and markedly at less than 26.2±3.4 (1.62±0.16 ml/l). 相似文献