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1.
Influence of genotype and such individual characteristics as locomotor and exploratory activity, aggressiveness and emotionality, was studied in male mice. Males F1 and males of the parent line PT had high level of social dominance. F1 had high level of aggressiveness, and low emotionality, medium level of locomotor and exploratory activity. Significance of these individual behavioural characteristics for dominant behaviour is discussed.  相似文献   
2.
The influence of opioid peptides (gamma- and beta-endorphins, leu- and met-enkephalins, as well as certain synthetic analogs of enkephalin) was investigated on organotypic cultures of rat spinal and sympathetic ganglia. The cellular composition and size of the zone of growth were evaluated on the basis of intravital observations and an analysis of the specimen obtained using the method of impregnation, according to Holmes and the detection of catecholamines with glyoxylic acid. It was established that under the action of all the investigated substances that possess high affinity for opiate receptors, growth of the neurites from an explant was enhanced, and the number of glial and fibroblastoid cells in the growth zone was increased. The effect was observed most distinctly on a model of sympathetic ganglia. The tested compounds exhibited a significant growth-stimulating effect in the range of concentrations 10–8–10–14 M. The maximum size of the growth zone of the explants of the sympathetic ganglia in the case of a mean effective concentration of the peptides 10–10 M by the third to fifth day of culturing was approximately 2–2.5 times this value in the control. The reaction was similar to the response of the nerve cells to nerve growth factor, used as a standard. Thus, the opioid peptides exhibit a pronounced growth effect on the structures of the nerve tissue under conditions of culture. It is suggested that this group of compounds, together with its currently well-known functions, may play a definite role in processes of the development and regenera-of nerve tissue.Institute of Experimental Cardiology, All-Union Cardiologic Science Center, Academy of Medical Sciences of the USSR, Moscow. Translated from Neirofiziologiya, Vol. 17, No. 4, pp. 550–557, July–August, 1985.  相似文献   
3.
Musashi-2(MSI2)是一种RNA结合蛋白质,对维持造血干细胞功能具有重要作用。研究表明,MSI2高表达能促进急性髓系白血病(acute myelocytic leukemia, AML)进展,但其作用机制尚不明确。本研究稳定沉默HL60细胞MSI2后,第1、2、3、4 d对照组的相对细胞生长率分别为1.931 ± 0.027、3.070 ± 0.073、4.017 ± 0.092和4.215 ± 0.246;敲减组分别为1.927 ± 0.035、2.564 ± 0.090、2.825 ± 0.097和3.223 ± 0.182,两组相比具有统计学差异,P<0.001;细胞凋亡明显增加(7.967% ± 0.698% vs 3.400% ± 0.322%., P<0.01);G0/G1期细胞比例明显增高(67.430% ± 4.390% vs. 50.360% ± 2.160%, P<0.01);NUMB蛋白明显上调,LEF1明显下降。环状RNA(circular RNA, circRNA)芯片筛选和荧光定量PCR验证显示,MSI2沉默组circRNA_001214表达水平是对照组3.48倍。这一结果也在NALM6细胞得到证实。进一步用生物信息学分析,显示circRNA_001214最可能与miR-1273a、miR-1273e和miR 5095结合,进而影响参与细胞凋亡相关基因(CYCS、AKT1、BAX、TNFRSF10A、TNFRSF10D)、Wnt信号基因(WNT4、WNT2B、WNT7B、 DKK2、SFRP1、CSNKE1和LEF1)以及参与细胞代谢相关基因(RPE, PGAM4, PGAM1, TAT, CBS、RPE、SUCLG2、PGAM4、PGAM1和 IDNK)。总而言之,MSI2可能通过干扰circRNA_001214生成,减少靶miRNA对凋亡、Wnt信号及细胞代谢相关基因表达的影响,促进细胞生长。  相似文献   
4.
R S Patiutko  S I Kozlova 《Genetika》1983,19(7):1198-1204
A case of a family of he proband suffering from ektrodaktyly, together with heart defect, cleft lip and palate is reported. The parents came to the genetic counselling center to get the genetic prognosis for a next child. All together 3 cases demonstrating different types of radial defects were registered in this pedigree. The authors discuss possible causes of clinical polymorphism and accent the complications of giving genetic prognosis in such cases.  相似文献   
5.
城市生态系统的模拟方法:灵敏度模型及其改进   总被引:5,自引:2,他引:3  
吕永龙  王如松 《生态学报》1996,16(3):309-313
评估城市生态系统的持续发展能力,探讨其持续发展对策是一个复杂的动态问题,需要运用动态的模拟方法进行。由德国著名生态控制论专家F.Vester和A.V.Hesler教授提出的“灵敏度模型”方法,将系统科学思想、生态控制论方法及城市规划融为一体,解释、模拟、评价和规划城市复杂的系统关系,是模拟城市生态系统很好的方法。本文对该方法进行了改进。改进后的“灵敏度模型”为评价城市持续发展能力、探讨其持续发展对策提供了新的思路。  相似文献   
6.
在主动脉与肾动脉缩窄造成的慢性心功能不全大鼠,血浆儿茶酚胺浓度增高;心脏β-肾上腺素受体(β-AR)数量增加,其中β_1-AR及其mRNA增加,而β_2-AR及其mRNA不变;左心房异丙基肾上腺素(ISO)浓度-收缩效应曲线右移;而心肌ISO浓度-cAMP蓄积曲线无显著改变;血淋巴细胞β-AR数量显著减少.结果提示心功能不全时心脏β_1-AR数量增多,但其介导的正性变力效应反而降低,在cAMP生成以后的信号转导过程或心肌收缩成分功能存在障碍,而血淋巴细胞β-AR的改变与心脏β-AR的功能改变平行.  相似文献   
7.
The published theory of kinetically controlled enzymatic peptide synthesis needed experimental verification. We carried out the measurement of the peptide yield and estimation of the key parameters alpha and beta for papain-catalyzed synthesis of Mal-L-Phe-L-Ala-LLeuNH(2) from Mal-L-Phe-L-AlaOMe and L-LeuNH(2). The experimental results demonstrate that this theory adequately describes the real process. (c) 1992 John Wiley & Sons, Inc.  相似文献   
8.
Effect of dalargin, an opioid peptide (a synthetic analogue of Leu-enkephalin), on proliferation and intensity of DNA synthesis of C6 glioma cells was studied. Specific conditions of cultivation were selected, with a low control value of proliferation, which permitted to assess growth-stimulating effect of the peptide. Growth curves were plotted to assess peptide activity, which demonstrated that reaction was a many-phase process: a significant increase in cell number under peptide effect was observed only at the beginning of the logarithm phase and at the beginning of the prestationary phase of the growth curve. Cell number increased on average by 25-27% in the presence of dalargin as compared to control. Reaction of glioma DNA synthesis to dalargin also demonstrates complexity of the process: the peptide changes DNA synthesis, but as a rule, this process has a three-phase character and is not directly associated with the duration of cultivation in the presence of dalargin. Effect of naloxone, an opiate receptor blocker, was analysed to assess the receptor mechanism. It was found that reaction for naloxone and for combined effect of naloxone and dalargin was not the same.  相似文献   
9.
Data on the experimental and clinical study of capreomycin in the treatment of tuberculosis are presented. It was shown that capreomycin had low activity with respect to the sensitive strain of Mycobacterium tuberculosis H37 Rv in vitro and the respective infection caused by it in mice. The activity of capreomycin in vitro with respect to streptomycin resistant strains was the same as that with respect to the sensitive strains, while in vivo it increased 3 times. Capreomycin showed a tendency to decreasing its activity with respect to strains highely resistant to canamycin only in vitro. The effect of capreomycin on tuberculosis infection caused by strains resistant to different concentrations of canamycin was the same as that on tuberculosis infection caused by sensitive strains. Cross resistance between florimycin (viomycin) and capreomycin was shown. Clinical trails of capreomycin revealed its moderate therapeutic efficiency, relatively low toxicity and an allergenizing effect on the host. Transient ventibulopatia without pronounced signs of ototoxic action was observed. The nephrotoxic effect was moderate and transient. It was observed predominantly at the peak of the allergic reactions to the antitubercle drugs. The data obtained during the study allow recommendation of capreomycin use in clinics as reserve drug when the causative agent is not resistant to florimycin. The drug should be used under regular control of the blood picture, electrolyte metabolism, state of the kidneys, auditory and vestibular apparatus.  相似文献   
10.
The ethylmorphine demethylase activity of the rat liver microsomes was higher in three-month animals (as compared to one-month), remained at a high level in the 12-month and decreased in old rats. The benzopyrene hydrolase activity increased in three-month animals, decreased in 12-month rats and remained the same with subsequent ageing of the organism. Asynchronicity of variations in the oxidation rate of different xenobiotics with ageing is considered as a result of changes in substrate specificity of the monooxygenase system due to metabolic peculiarities which reflect the age development of the organism and extinction of the reproduction function.  相似文献   
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