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481.
E A Ved'mina N A Pasternak V A Shenderovich T P Zhuravleva I T Andrusenko 《Antibiotiki》1979,24(10):746-750
Sensitivity to lysozyme of the representatives of various species of gramnegative microflora (476 strains) was studied with a new modified procedure, which is more exact and economic as compared to the method of serial dilutions in agar. High resistance of Eltor vibrio cholerae and Pseudomonas to lysozyme was found. Cultures of various sensitivity levels to lysozyme were detected among Aeromonas, enteropathogenic E. coli and NAG-vibrios. 相似文献
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N A Pasternak E A Ved'mina I T Andrusenko V A Shenderovich T P Zhuravleva 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1983,(7):55-59
The identical character of the action of crude V. cholerae enterotoxin on the anaerobic dehydrogenases of the UV-2 mutant of S. aureus 209 p and the surviving culture of Ehrlich's carcinoma has been revealed. The range of this action is linked with the concentration of the toxin and varies from the stimulation of cell dehydrogenases to their complete suppression. The rapid method for the titration of the enterotoxin in the dehydrogenase suppression test with the use of the bacterial model is proposed. 相似文献
484.
Comparison of naloxonazine and beta-funaltrexamine antagonism of mu 1 and mu 2 opioid actions. 总被引:1,自引:0,他引:1
beta-Funaltrexamine (beta-FNA) irreversibly blocks morphine analgesia, lethality and its inhibition of gastrointestinal transit, confirming that these actions involve mu receptors. In dose-response studies, beta-FNA antagonized all the actions with similar potencies (ID50 values of 12.1, 11.3 and 12.3 mg/kg, respectively). beta-FNA also reduced intra-cerebroventricular and intrathecal DAMGO analgesia equally well (ID50 values of 6.09 and 7.7 mg/kg, respectively). Naloxanazine blocked systemic morphine analgesia (ID50 value 9.5 mg/kg) and supraspinal DAMGO analgesia (ID50 value 6.1 mg/kg) as potently as beta-FNA. However, against spinal DAMGO analgesia, morphine's inhibition of gastro-intestinal transit or lethality, naloxonazine (ID50 values 38.8, 40.7 and 40.9 mg/kg, respectively) was significantly less active than beta-FNA (p less than 0.05). beta-FNA remains a valuable tool in the classification of mu opioid actions. Within the mu category, actions can be defined as either mu 1 (naloxonazine-sensitive) or mu 2 (naloxonazine-insensitive). 相似文献
485.
1. During fusion of chick-embryo myoblasts in culture, the surface membrane is affected as follows. Uptake of 2-aminoisobutyrate and 2-deoxyglucose, each of which is concentrated 20-fold relative to its concentration in the medium, is unaltered; uptake of alpha-methyl glucoside and choline (15 mM), each of which equilibrates relative to its concentration in the medium, approximately doubles. An approximate doubling also occurs in iodinatable surface protein (and in total protein) and in cell surface area as judged by light-microscopy. Adenylate cyclase (in the absence or the presence of fluoride) increases by more than 2-fold. 2. It is concluded that, during myoblast fusion cells increase in size, and this is reflected in an increased rate of simple diffusion; the rate of facilitated processes such as the uptake of amino acids and sugars, on the other hand, remains unaltered, though the activity of certain enzymes is increased. These results indicate that specific changes in the function of surface membrane occur during myoblast fusion in vitro. 相似文献
486.
Phenanthroline treatment of growing cultures of the free-living nematode Panagrellus silusiae was used to lower the degree of hydroxylation of nascent collagen chains at the polysomal level. Under these conditions, the bound pentasome-hexasome fraction provided substrate for prolyl hydroxylase. When this polysomal fraction was subsequently tested in a cell-free wheat germ system, collagenase-susceptible translation products were observed after sodium dodecyl sulfate-acrylamide gel electrophoresis. The electrophoretic mobilities of each of these four major collagen products were similar to four collagens that are isolated from intact cuticles. In addition, purified polysomal RNA that adhered to unmodified cellulose directed the synthesis of four pepsin-resistant polypeptides that had molecular weights that coincided with four pepsin-resistant collagens that can be purified from the cuticle of this species. Thus, the polysomal site of the messenger RNAs for the cuticular collagens of P. silusiae was located. Although precursor forms of the cuticular collagens were not produced in the cell-free system, the question whether additional amino acid segments occur on the primary translational products of the cuticular collagens in vivo remains open. 相似文献
487.
Luise Pasternak Günter Pasternak Uwe Karsten 《Cancer immunology, immunotherapy : CII》1978,3(4):273-275
Summary Soluble tumor extracts were isolated from a UV light-induced mouse sarcoma by 3 M KCl extraction followed by 2 M (NH4)2SO4 precipitation. The precipitates dissolved in phosphate buffered saline (PBS) produced transplantation resistance against syngeneic cell inocula of the tumor at a restricted dose range. While 1.0–1.2 mg of protein per mouse were effective, double this dose was not. An extract prepared from ascitic fluid of tumor-bearing mice showed effects similar to one prepared from tumor cells. 相似文献
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