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排序方式: 共有459条查询结果,搜索用时 312 毫秒
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A. N. Utkina Yu. Yu. Cherkis M. N. Kozlova V. L. Kozlov 《Metal Science and Heat Treatment》1982,24(4):270-273
Conclusion To ensure the required characteristics of the diffusion layer in heat-resistant steels, it is recommended to subject them to two-stage nitriding: saturation at 950°C for 2 h in endogas with an addition of 12% natural gas and 4% ammonia, lowering the temperature to 900°C, holding for 5 h in endogas with an addition of 6% natural gas and 4% ammonia; exchange of gas 6 times.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 4, pp. 34–36, April, 1982. 相似文献
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The influence of socioeconomic and nutritional status on menarche in Nigerian school girls 总被引:1,自引:0,他引:1
EA Abioye-Kuteyi EO Ojofeitimi OI Aina F Kio Y Aluko O Mosuro 《Canadian Metallurgical Quarterly》1997,11(3):185-195
Two once-daily electroconvulsive shocks (ECS) produced retrograde amnesia in rats trained on a Hebb-Williams maze; Verapamil (12.5 mg/kg, i.p.) or felodipine (10 mg/kg, p.o.) administered half an hour before each ECS attenuated this ECS-induced amnesia. Hence, these drugs may hold promise for the containment of amnesia induced by electroconvulsive therapy (ECT). Speculatively, one or more of several mechanisms may be involved: cerebral vasodilatation, enhancement of cholinergic tone, and inhibition of calcium-mediated impairment of neuronal function. These drugs may also act by attenuating the systolic surge in blood pressure during ECT, thereby decreasing edema due to cerebral hyperperfusion, as well as decreasing the possible transfer of potentially neurotoxic macromolecules through a putative breach in the blood-brain barrier. 相似文献
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Homozygous and hemizygous deletions of 9p21 are the earliest and most common genetic alteration in bladder cancer. The identification of two cell cycle regulators, CDKN2 and CDKN2B, that map to the common region of deletion has prompted the hypothesis that they are critical tumor suppressor genes in this malignancy. However, controversy as to whether these genes are the only or even the most important target in bladder cancer oncogenesis remains. To more clearly determine the effect of these 9p21 alterations, we mapped the homozygous deletions and performed a detailed mutational and expression analysis for CDKN2, CDKN2B and a closely linked gene, methylthioadenoside phosphorylase (MTAP), in 16 established bladder cancer cell lines. Nine of the 16 lines exhibit large (30 to > 2000 kb) homozygous deletions on 9p21. All deletions include at least one exon of CDKN2, eight of nine include CDKN2B, and six of nine include MTAP. MTAP function correlates with the genomic deletions. SSCP and sequence analysis does not reveal any inactivating point mutations of CDKN2 or of CDKN2B in any of the cell lines without homozygous deletions, and all express the CDKN2 and the CDKN2B mRNA as well as the encoded p16 protein. The p16 protein levels vary widely and are correlated with absent pRb expression. We conclude that the 9p21 deletions in bladder cancer usually inactivate the CDKN2. CDKN2B, and MTAP genes but that CDKN2 is the most common target. Other mechanisms for inactivating this gene in bladder cancer appear to be uncommon. 相似文献
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Fifty-eight new anonymous simple sequence repeats (SSR) were generated and mapped to various rat chromosomes. Among them two genes (rat homologs for human cadherin-14 and mouse fibroblast growth factor-related protein) were mapped on Chromosomes (Chrs) 2 and 11 respectively. The majority of markers were generated from a small insert genomic library specific to Chr 11, 13, 14, and 15. Twenty new markers were mapped to Chr 13, which is known to contain a blood pressure quantitative trait locus (QTL). Several approaches to obtain microsatellite markers are described. The protocols and newly generated markers should be useful for ongoing rat genome project. 相似文献
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VA Poberskaia LV Kozhelupenko EA Kradinova OI Dement''eva 《Canadian Metallurgical Quarterly》1995,75(4):10-13
A favourable effect of sanatorium treatment on the key body functions was found in children with thyroid hyperplasia consequent to environmental pollution due to Chernobyl accident. It is emphasized that balneofactors in the above children should be used in sparing regimens. 相似文献
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V M Krasnopevtsev L S Trofimenko A V Istomin Iu A Noarov T I Kozlova 《Voprosy pitaniia》1989,(5):40-43
Actual nutrition, health state and physical working capacity were studied in schoolchildren of three age groups after intake of the polyvitamin "Undevitum" during a month. The results of the investigation conducted have shown that prophylactic measures produced a positive effect on the schoolchildren aged from 11 to 13 and from 14 to 17 years who received 1 degree of "Undevitum" daily. No positive effect was recorded in schoolchildren aged 7-10 years who received 1 degree of "undevitum"/day, every other day. 相似文献