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101.
ED Kouvelas CE Savakis ET Tzebelikos G Bonatsos S Mitrossilis 《Canadian Metallurgical Quarterly》1976,32(9):1136-1138
The specific activity of histamine methyltransferase of rat brain increases rapidly from the 16th until the 25th day of gestation (7 days after birth). The specific activity of phenylethanolamine-N-methyl-transferase shows a rapid increase during the 1st and the 2nd week after birth, the adult values being obtained by the end of the 2nd week. 相似文献
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Cloned genomic DNA sequences corresponding to various regions of the human type II procollagen gene were used to analyze the DNA from 78 normal volunteers. Southern hybridization experiments detected polymorphic HindIII, BamHI, and EcoRI sites. The presence of the polymorphic HindIII site results in a 7.0-kilobase (kb) band, and the absence of this site results in a 14.0-kb band. When present, the BamH1 polymorphic site yields a 4.8-kb band, and when absent, yields a 7.2-kb band. The presence of the EcoRI polymorphic site results in a 3.7-kb band, and its absence results in a 7.0-kb band. Each polymorphic site was mapped. Analyses of the data demonstrated that the sites are present in overall gene frequencies of .39 for HindIII, .04 for BamHI, and .02 for EcoRI. Gene frequencies of the polymorphic sites were also studied with respect to race. The polymorphic sites are present in a Hardy-Weinberg distribution in the study population. Study of an extended family demonstrated that the segregation of the HindIII polymorphic site is consistent with Mendelian inheritance. 相似文献
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106.
葛思华 《Canadian Metallurgical Quarterly》2011,20(3)
焦点解决短期心理辅导咨询的理论近年来广受关注,运用这一理论解决大学新生适应性问题具有很强的实用价值.在厘清焦点解决短期心理咨询基本理念的基础上,探索其适用的范围,研究运用过程的有关实务,以及实践过程中需要注意和整合的问题,使得大学新生心理辅导更富效率. 相似文献
107.
SR Dager ME Layton W Strauss TL Richards A Heide SD Friedman AA Artru CE Hayes S Posse 《Canadian Metallurgical Quarterly》1999,156(2):229-237
OBJECTIVE: Since there is limited information concerning caffeine's metabolic effects on the human brain, the authors applied a rapid proton echo-planar spectroscopic imaging technique to dynamically measure regional brain metabolic responses to caffeine ingestion. They specifically measured changes in brain lactate due to the combined effects of caffeine's stimulation of glycolysis and reduction of cerebral blood flow. METHOD: Nine heavy caffeine users and nine caffeine-intolerant individuals, who had previously discontinued or substantially curtailed use of caffeinated products because of associated anxiety and discomforting physiological arousal, were studied at baseline and then during 1 hour following ingestion of caffeine citrate (10 mg/kg). To assess state-trait contributions and the effects of caffeine tolerance, five of the caffeine users were restudied after a 1- to 2-month caffeine holiday. RESULTS: The caffeine-intolerant individuals, but not the regular caffeine users, experienced substantial psychological and physiological distress in response to caffeine ingestion. Significant increases in global and regionally specific brain lactate were observed only among the caffeine-intolerant subjects. Reexposure of the regular caffeine users to caffeine after a caffeine holiday resulted in little or no adverse clinical reaction but significant rises in brain lactate which were of a magnitude similar to that observed for the caffeine-intolerant group. CONCLUSIONS: These results provide direct evidence for the loss of caffeine tolerance in the human brain subsequent to caffeine discontinuation and suggest mechanisms for the phenomenon of caffeine intolerance other than its metabolic effects on elevating brain lactate. 相似文献
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Excretion was studied of catecholamines and diphenilamine (DOPA) in 310 patients with carcinoma of the stomach and large intestine and 43 patients with non-malignant diseases. The oncological patients showed decrease in activity of the mediator link of the sympathoadrenal system (SAS) as well as its reserves but there was no association with sex, age, location or histological structure. Three types of SAS functioning were identified, such as compensation, overstrain and emaciation. Surgical intervention led to activation of the hormonal link and exhaustion of the system's reserves. Two kinds of sympathoadrenal response to stress were described--adequate and inadequate. In the former type, phases of stress remain as they are, unchanged, as are time periods of formation thereof, while under the latter one time periods of the phases formation or formation thereof get disordered. 相似文献