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991.
A G Chuchalin V A Babushkina V Ia Arion R D Aspetov T B Sha?khinova 《Biulleten' eksperimental'no? biologii i meditsiny》1984,98(7):76-78
A study was made of the effect of T-activin on the biosynthesis of immune gamma-interferon. It was shown that in 27% of patients with chronic nonspecific pulmonary diseases, production of gamma-interferon by lymphocytes was substantially reduced during exacerbation of inflammatory process in the lungs. It was discovered that T-activin was not an interferon inductor but enhanced its synthesis in patients with a low capacity of producing immune interferon even at small doses of interferon inductor. The preparation does not produce any effect on this process in normal subjects and in patients showing the normal level of gamma-interferon. Thus T-activin can be used for stimulation of interferonogenesis. 相似文献
992.
Background
Chow and Liu showed that the maximum likelihood tree for multivariate discrete distributions may be found using a maximum weight spanning tree algorithm, for example Kruskal's algorithm. The efficiency of the algorithm makes it tractable for high-dimensional problems. 相似文献993.
Gene frequencies and microdifferentiation among the Makiritare Indians. I. Eleven blood group systems and the ABH-Le secretor traits: a note on Rh gene frequency determinations. 总被引:11,自引:8,他引:3
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H Gershowitz M Layrisse Z Layrisse J V Neel C Brewer N Chagnon M Ayres 《American journal of human genetics》1970,22(5):515-525
994.
V S Pikaliuk 《Arkhiv anatomii, gistologii i émbriologii》1991,100(5):5-12
In the experiment performed on 175 white male rats by means of a complex of morphological, biochemical and biomechanical methods peculiarities of structure, growth, outline formation and mineralization of the skeletal bones have been investigated under a toxic lesion of the organism with pesticides (chlorophose and keltan) and at a simultaneous administration of antioxidants of various groups (tocopherol, ionol, sodium selenit). Osteotoxic effect of the pesticides, manifested as an inhibition of bone growth, as a disbalance of mineral saturation and their composition, as a decrease in indices of firmness is leveled by means of therapeutic doses of the antioxidants. The stabilizing effect of the antioxidant applied correlates to the manifestation of the pesticides osteotoxic effect, to the ability of their cumulation in the organism and is directly connected with the supposed mechanism of damaging effect to the organism and/or cell. The expressiveness of the toxic effect of the chemical poison, in its turn, is defined not only by the dose, mechanism and duration of the effect, but by age peculiarities of the organism and by functional state of its reactivity. When the poisons are applied for a long time, in order to level their osteotoxic effect, a multiple increase of therapeutic doses of the antioxidants and a combined potentiation of their effect are necessary. 相似文献
995.
996.
997.
Sergey V. Budaev 《Ethology : formerly Zeitschrift fur Tierpsychologie》2010,116(5):472-480
Principal component (PCA) and factor analysis (FA) are widely used in animal behaviour research. However, many authors automatically follow questionable practices implemented by default in general‐purpose statistical software. Worse still, the results of such analyses in research reports typically omit many crucial details which may hamper their evaluation. This article provides simple non‐technical guidelines for PCA and FA. A standard for reporting the results of these analyses is suggested. Studies using PCA and FA must report: (1) whether the correlation or covariance matrix was used; (2) sample size, preferably as a footnote to the table of factor loadings; (3) indices of sampling adequacy; (4) how the number of factors was assessed; (5) communalities when sample size is small; (6) details of factor rotation; (7) if factor scores are computed, present determinacy indices; (8) preferably they should publish the original correlation matrix. 相似文献
998.
999.
N. Gilboa-Garber V. Zakut L. Mizrahi 《Biochimica et Biophysica Acta (BBA)/General Subjects》1973,297(1):120-124
Production of cholinesterase by a pyocyanin-producing strain of Pseudomonas aeruginosa, isolated from a patient and grown in the presence of acetylcholine as the main source of carbon, was described. The enzyme activity was detected in suspensions of intact bacteria and in their subcellular preparations. Like the acetylcholinesterase of the electric eel, as opposed to that of the erythrocytes, this bacterial enzyme was inhibited by specific antiserum produced against it in rabbits. The production of the enzyme was found to be sensitive to catabolite repression and to require external cyclic AMP, but not 5′-AMP for the elimination of this repression. Cyclic AMP alone, without the inducer, did not stimulate the production of the enzyme. 相似文献
1000.