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921.
Theoretical models for cooperative steady-state ATPase activity of myosin subfragment-1 on regulated actin 总被引:3,自引:0,他引:3
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Recent theoretical work on the cooperative equilibrium binding of myosin subfragment-1-ADP to regulated actin, as influenced by Ca2+, is extended here to the cooperative steady-state ATPase activity of myosin subfragment-1 on regulated actin. Exact solution of the general steady-state problem will require Monte Carlo calculations. Three interrelated special cases are discussed in some detail and sample computer (not Monte Carlo) solutions are given. The eventual objective is to apply these considerations to in vitro experimental data and to in vivo muscle models. 相似文献
922.
Axial distortion of airways in the lung 总被引:2,自引:0,他引:2
Kallok M. J.; Lai-Fook S. J.; Hajji M. A.; Wilson T. A. 《Journal of applied physiology》1983,54(1):185-190
923.
T M Zheltikova V M Berzhets A D Petrova-Nikitina A Kh Kanchurin 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1986,(6):80-83
The acarological+ study of dust samples from the homes of allergic patients and normal persons in Moscow mite antigens were detected, respectively, in 66.7% and 38.1% of homes. The indirect mast cell degranulation test and the brain gliacyte volume change test in white rats gave similar results. The occurrence of Dermatophagoides pteronyssinus was approximately twice as great of D. farinae, and the numerical prevalence of the former species over the latter one was 1.3-fold. Dermatophagoides mites occurred in the homes of allergic patients 1.8-2.3 times as frequently as in the homes of normal persons. 相似文献
924.
925.
Summary The rhizosphere microflora of arecanut palm under continuous application of organic manures and inorganic fertilizers was
studied. The nutrients applied are 100 g N, 40 g P2O5 and 140 g K2O/palm/year in the form of organics and inorganics. The application of organic manure increased the microbial population.
The increase in microbial population was observed between the rhizosphere samples collected at 0–30cm and 30–60 cm depths.
The surface cultivation of soil increased the microbial population.Trichoderma sp. andAspergillus sp. dominated in therhizosphere of arecanut palm.
Contribution No. 208. Central Plantation Crops Research Institute, Vittal-574243, Karnataka, India. 相似文献
926.
Auromomycin and macromomycin from the organism Streptomyces macromomyceticus have been crystallized. The X-ray diffraction pattern of crystals of each molecule is consistent with space group P21212 with cell parameters for auromomycin, and for macromomycin. Diffraction analysis of auromomycin is in progress. 相似文献
927.
Histological and electron-microscopic radioautographic investigations of regenerating medullar tissue were performed in rabbits following curettage. Low differentiated connective tissue cells were shown to possess the highest proliferative activity. DNA synthesis mainly took place in low differentiated, endothelial and osteogenic cells. It is suggested that low differentiated cells take part in histogenesis of regenerating medullar tissue, including osteo- and angiogenesis. 相似文献
928.
Iu I Afanas'ev O i Mikha?lov V I Nozdrin G V Nikitenkova M I Rytikova 《Biulleten' eksperimental'no? biologii i meditsiny》1986,101(1):22-24
Human and animal blood smear staining with PAPh has revealed mononuclear leukocyte-erythrocyte aggregates. Administration of retinoic acid increased concentration and dimensions of these aggregates and was followed by preferential accumulation of PAPh-negative osmotically unstable erythrocytes. Similar changes were detected in the blood samples of women engaged in the production of retinoic acid. Aggregate concentration showed positive correlation with erythrocyte sedimentation rate and no correlation with prothrombin time. 相似文献
929.
930.
A A Dmitrovski? Iu V Ershov V Ia Bykhovski? 《Prikladnaia biokhimiia i mikrobiologiia》1992,28(2):199-204
The authors studied the effect of dithiothreitol (DTT), carotenoids and protease inhibitors on stabilization and protection of the enzyme catalysing the conversion of beta-carotene into retinal during the enzyme isolation from the rabbit small intestine. The addition of 1 mM DTT into the homogenization mixture increased the activity of the enzyme 5 times compared with control. The additional introduction of 0.7 mg/ml soybean trypsin inhibitor or 2.10(-4) M phenylmethylsulfonyl fluoride increased the enzyme activity 2.1 and 1.2 times, respectively. Lutein, beta-carotene and lycopene at a concentration of 10 mg/ml increased the enzyme activity 2.1, 1.9 and 1.6 times respectively. The effects of DTT, lutein and the protease inhibitor depended on their concentrations and was of an independent additive character. The maximum activity of the isolated enzyme exceeded the control without DTT 15 times. 相似文献