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排序方式: 共有1579条查询结果,搜索用时 15 毫秒
1.
2.
LV Osadchuk VV Gul'tiaeva AA Filimonenko L Jalkanen 《Canadian Metallurgical Quarterly》1996,82(5-6):102-108
15.7% of spermatozoa were found to be abnormal in silver fox males during their first reproductive season. The total number of spermatozoa and the abnormal spermatogenesis remained unchanged during mating season. Sexual stimulation increased the testosterone level only at the beginning of the mating season. 相似文献
3.
An in-vitro effect of nonapeptide neurohormone vasotocin on thyroid and interrenal glands was studied in hybrid of Siberian and Lena sturgeons [correction of salmons] at light microscopy level using morphometric method. At a concentration of 0.1 and 1 nmol/l vasotocin was shown to exert undirectional stimulating effect on the thyroid and interrenal gland functions. In the presence of vasotocin at a concentration of 1 nmol/l in culture media the activity of glands is even more pronounced than under the influence of adenohypophyseal hormones, adrenocorticotropic (8 x 10 ng/ml) and thyrotropic (5 ng/ml). 相似文献
4.
VV Flegontova 《Canadian Metallurgical Quarterly》1998,114(4):32-36
A total of 280 children and adolescents with congenital and acquired mandibular defects and deformations were treated. The main principle in the treatment of such children is to begin treatment as early as possible. Stages of rehabilitation and scope of therapeutic measures for each stage are determined. The best results were attained in patients administered multiple-modality treatment by surgical, orthodontic, physiotherapeutic methods and therapeutic exercises at an early age immediately after the defect was diagnosed. 相似文献
5.
In experiments on male rabbits with the lack of insulin it is been revealed violations after the past immobilization the intensivity and duration of neutrophilic leukocytosis decrease, contents of lysosomes in neutrophils, activity of acid phosphatase. By lysosomal ferments don't determine the can observer discordance of processes of coagulation, fibrinolysis, kininogenesis. 相似文献
6.
Samples of three Indian coals, of widely differing origin and rank, were subjected to flash pyrolysis at a temperature of about 1150 °C for 30 s in vacuo, and under atmospheres of nitrogen, argon, ammonia, and perdeuterobenzene. The gaseous products of the pyrolyses were analysed by infra-red and mass spectroscopy and by gas chromatography. Observed variations in gas compositions are discussed relative to the possible mode of influence by the pyrolytic atmospheres. It would appear that the pyrolytic atmosphere is an important factor in determining the composition of the pyrolysis products; the influence of nitrogen, argon and perdeuterobenzene is a physical one, leading especially to higher yields of olefins. 相似文献
7.
Summary The fatty acid composition of a number of vegetable oils and of two synthetic mixtures of methyl esters are compared by gas-liquid
chromatography and by standard methods. The calculated iodine values from G.L.P.C. results are in good agreement with measured
iodine values and are indicative of the reliability of the G.L.P.C. values. Standard methods gave lower values for linoleic
acid and higher values for linolenic acid than did G.L.P.C. This deviation was particularly evident in oils with a high proportion
of linolenic acid,e.g., linseed oil. The results of G.L.P.C. are considered to be accurate to within one unit percentage. Thermal stability of the
polyester polymers can be improved by using 1,4-butanediol or ethylene glycol as the polyols instead of diethylene glycol.
Issued as N.R.C. No. 5373.
Presented at 32nd annual fall meeting, American Oil Chemists' Society, October 20–22, 1958, Chicago, Ill.
National Research Council of Canada Postdoctorate Fellow, 1957 相似文献
8.
Ch. Vasavi G. Suresh Kumar M. S. N. Murty 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2016,20(3):1093-1104
This paper deals with the fuzzy set-valued functions of real variables on time scale whose values are normal, convex, upper semicontinuous and compactly supported fuzzy sets in \(\mathbb {R}^{n}\). We introduce and study the fundamental properties of new class of derivative called generalized delta derivative (\(\Delta _{g}\)-derivative) and generalized delta integral (\(\Delta _{g}\)-integral) for such fuzzy functions. 相似文献
9.
10.
Oligonitrophilic bacteria were cultivated on a medium containing only 2.5--10.0 mg/litre of nitrogen compounds. They assimilated elementary nitrogen only after utilization of these nitrogen compounds during growth and formation of nitrogen-fixing enzyme system. Their cells grown on a medium containing high concentrations of bound nitrogen did not fix nitrogen during further incubation in the atmosphere of 15N; therefore, the enzymes involved in nitrogen fixation were induced. These organisms are characterized by diauxia during their growth on media containing "start" doses of nitrogen. Enzymes catalysing nitrogen fixation in azotobacter are also induced. But, contrary to oligonitrophilic bacteria, the azotobacter does not require nitrogen compounds in the medium in order to adapt to molecular nitrogen, and its growth curve is not of a biphasal character. These data and the evidence of other authors suggest that all nitrogen-fixing microorganisms are characterized by the induced, not constitutive, enzymes involved in reduction of molecular nitrogen. 相似文献