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991.
The amino acid composition of cell walls and surface proteins, isolated from virulent (M+) and avirulent (M-) streptococcal strains (group A, type 29) has been determined by the method of E. H. Beachey et al. The kinetics of the lysis and proteolysis of streptococcal cell walls with muramidase and protease obtained from Actinomyces levoris and streptolysin has been studied. The constants describing the progress rates of these processes has been determined; their values in case of both lysis and proteolysis are higher in virulent strains than in avirulent ones.  相似文献   
992.
993.
The synthesis of three hepatitis B surface antigens derived from S and pre-S proteins (adw S(140-147), [Tyr148] adw S(139-148), and adw pre-S(120-145)) has been accomplished by the continuous flow Fmoc-polyamide solid phase method. The use of different scavengers and trimethylsilyl bromide (TMSBr) in trifluoroacetic acid as deprotecting procedures is discussed.  相似文献   
994.
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996.
Results of the study of taurine and dipeptide Tyr-Tyr effect on the threshold values of functional lesions of the myocardium and heart defibrillation are reported. The experiments were carried out on 27 narcotized mongrel dogs weighing 12-30 kg. Defibrillation was performed using Lifepak-7 defibrillator (USA). Lesion threshold (LT), defibrillation threshold (DT) and electrotherapeutic index (ETI) as a LT:DT ratio were determined. In 14 experiments (control group) these parameters were evaluated during 3 h. In group 1 (6 experiments) taurine (100 mg/kg) was infused intravenously by the end of the 1st hour, in group 2--Tyr-Tyr (25 mg/kg). It was shown that infusion of taurine did not have a noticeable effect of the LT, DT and ETI values. Infusion of Tyr-Tyr resulted in an increase in LT and DT. The possibility to use dipeptide Tyr-Tyr in the complex of measures aimed at ceasing ventricular fibrillation is discussed.  相似文献   
997.
Journal of Ichthyology - The paper considers the effect of the Sea of Azov salinization on the food supply to anchovy Engraulis encrasicolus maeoticus as the level of salinity was rising from 12.7...  相似文献   
998.
Relationships between the strongyloid nematodesRugopharynx delta, R. zeta, R. omega, R. longibursaris, R. mawsonae andR. sigma, all from macropodid marsupials, were investigated using allozyme data. The phylogenetic trees derived from the electrophoretic data set were congruent with those of the hosts and were consistent with the hypothesis that the species complex originated in pademelons of the genusThylogale and diversified in rock-wallabies (Petrogale spp.) and scrub wallabies of the subgenusNotamacropus. Host switching is evident only between closely related macropodid taxa.  相似文献   
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