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排序方式: 共有250条查询结果,搜索用时 15 毫秒
31.
A F Usynin V V Khlystov V S Pavlenko 《Biulleten' eksperimental'no? biologii i meditsiny》1987,103(3):361-363
The ultrastructure of sinus and atrioventricular nodes was studied in white rats with experimental myocardial infarction. 24 hours after the induction of the disease mitochondrial enlargement characterized by the increase in their area, decrease in the number of cristae and the decline in the rate of mitochondrial energy effectiveness was detected. Different degrees of nuclear chromatin aggregation and membrane permeability for colloidal lanthanum were observed. Characteristic types of conduction cellular lesions were revealed in experimental myocardial infarction. 相似文献
32.
Sidiakin VG Pavlenko VB Kulichenko AM Gorelova EV Pavlenko OM 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1997,83(1-2):28-34
Activity of 50 dopamine and 67 non-dopamine neurons was studied during motivated behavioural actions in the cat brain black substance. 66% of former and 88% of latter neurons modified their activity before and during autoinitiated voluntary movements. The data obtained suggest that dopamine neurons are involved in organisation of movements in behavioural actions with cognitive components. 相似文献
33.
SSKOIDE 《Cell research》1997,7(1):51-59
INTRODUCTIONEpidermalgrowthfactor(EGF)wasinitiallyisolatedandpurifiedfromthesubmaxillarygland(SMG)ofmalemouse[1].Itisapolypeptidecomposedof53aminoacidresidues[2].Itinfluencescellproliferationanddifferentiationandmodulatesthegrowthanddevelopmentofmammalianorgans[3--7].AnoteworthyfindingisthatextirpationofmouseSMGresultsinamarkedreductionofserumEGFconcentrationassociatedwithanimpairedspermatogenesis[3].ThisfindingsuggeststhatEGFmayregulatespermproductionanddifferentiation.Inhumantest… 相似文献
34.
基于戴云山固定样地黄山松群落物种组成与结构研究 总被引:1,自引:0,他引:1
黄山松是亚热带中部山区主要建群种,研究其物种组成及群落结构对探讨中亚热带植被演替规律具有重要意义。戴云山自然保护区分布有大面积黄山松群落,该研究采用网格布点法,建立86块(25.82 m×25.82 m)共5.7 hm~2固定样地,对样地内黄山松群落的物种组成特征、分布区类型、胸径和树高结构、空间分布格局4个方面特征进行了探讨。结果表明:(1)样地内共出现木本植物32 603株219种,隶属于59科108属。乔灌木优势种有黄山松、马尾松、木荷、肿节少穗竹、岩柃、窄基红褐柃等,其中稀有种和偶见种分别占总物种数的33.79%、25.75%和45.21%、24.66%。(2)在区系分布类型上,热带分布类型的科属多于温带分布类型的科属,热带分布类型中又以泛热带分布类型,温带分布类型以北温带占据最大比例。(3)样地内优势种的胸径分布呈倒"J"型,表明更新状态良好。垂直结构上,各优势种树高为倒"J"型或近似倒"J"型。黄山松和其他优势乔木大部分树高为4~10 m,灌木除短尾越桔0~1 m个体数最多外,其他优势灌木1~2 m个体数最多。(4)经计算,样地内乔灌木各优势种均呈聚集分布,聚集程度有所差异,乔木层黄山松最低,灌木层短尾越桔最低。该研究结果表明戴云山保护区黄山松群落物种组成丰富、更新良好,反映了亚热带高山针叶林的典型特征,其空间分布格局可能与取样方式等因素有关。 相似文献
35.
E.?V.?EismontEmail author S.?A.?Makhin A.?V.?Bakunova A.?I.?Kaida V.?B.?Pavlenko 《Human physiology》2017,43(3):274-279
We studied the frequency and amplitude properties of the EEG μ rhythm in children (n = 38) aged 4–14 years under the condition of visual fixation (VF) on a video image of a computer mouse, as well as the parameters of its desynchronization during the tasks involving self-controlled performance, observation, imitation, and auditory recognition of the hand circular movements (SPM, OM, IM, and ARM, respectively) with a computer mouse. We observed age-related increment in the modal frequency of μ rhythm in loci C 3 and C z. During the SPM process, a significant decrease in the amplitude of μ rhythm was found in loci C 3 (26.7%) and C z (10.3%); during the OM, in locus C z only (9.9%). The effects of the μ rhythm desynchronization during both self-paced and observed movements might be an evidence of well-developed neural matching mechanisms that provide the processes of performing and observing similar actions in children aged 4 to 14 years. During the IM, the desynchronization of μ rhythm was significant in loci C 3 (27.4%) and C z (15.3%). We hypothesize that the statistically significant increase (from SPM to IM) in the depression of μ rhythm in locus C z is likely to be an effect of a social gaming context common for the situations when children imitate the movements of adults. The index of desynchronization of μ rhythm under the studied conditions did not depend on the age of children. Possible relations of identified modulations of the μ rhythm to the activity of the mirror neuron system were also discussed. 相似文献
36.
37.
Reflection of Anxiety in the Characteristics of Evoked EEG Potentials in 10- to 11-Year-Old Children
We studied the peculiarities of the amplitude/time parameters of evoked EEG potentials (EPs) and event-related potentials
(ERPs) in 10- to 11-year-old children characterized by low and high anxiety levels. The latter levels were estimated using
the scale of the manifest anxiety test of Prikhozhan and projective techniques (“House–Tree–Person,” HTP, and the Lüscher
color test). For children with a high anxiety level, the amplitudes of the following EP components and ERPs were lower than
those in low-anxiety children of the same age: P1 (predominantly in the occipital region of the left hemisphere), P2 (in the
right occipital region), and Р300 wave (in different loci of both hemispheres). In high-anxiety children, we also more frequently
observed increased amplitudes of the N2 component in the left parietal and right occipital regions. High-anxiety individuals
were characterized by longer latencies of component P1 (mostly in the right frontal and left central regions) and, at the
same time, shorter latencies of component N1 (in the parietal and occipital regions of the left hemisphere and also in the
right temporal region). Thus, we found that the amplitude/time characteristics of a few EP components and ERPs in children
with high anxiety levels differ statistically significantly from the parameters of corresponding EPs/ERPs in individuals of
the same age but with low anxiety levels. 相似文献
38.
We estimated the efficacy of using the technique of feedback (FB) by EEG characteristics (EEG-FB, neurotherapy) with the aim
of reducing increased anxiety levels in healthy 10- to 14-year-old children. The anxiety level was estimated using the Prikhojan
anxiety test, the Spielberger–Khanin questionnaire, and the House–Tree–Person projective drawing technique. Positive effects
of series of neurotherapy sessions were obvious. After training was completed, we observed significant increases in the ratios
of the amplitudes of alpha and theta rhythms, semsorimotor and theta rhythms, as well as of the modal frequency of the EEG
alpha rhythm in tested persons of the experimental group (n = 7). In the control group (n = 10), changes in these values did not reach the significance level. In the experimental group of tested persons subjected
to EEG-FB sessions, the anxiety level decreased appreciably; in addition, the indices “feeling of inferiority” and “frustration”
decreased significantly. In the control group, alterations of these psychological indices were not unidirectional. Therefore,
modifications of the EEG pattern, which occurred in the course of training and were accompanied by a decrease in the anxiety
level in the experimental group, can be indicative of the expediency of EEG-FB for the reduction of high anxiety levels in
children and teenagers. 相似文献
39.
放化疗综合应用是癌症治疗中的常用方法。研究表明,放化疗综合应用可以有效地控制杀伤肿瘤,但过程中对正常细胞的毒副作用严重制约着放化疗的剂量和疗效。如何在有效杀伤肿瘤细胞的同时减轻放化疗综合应用中对正常细胞的毒副作用已经成为探索更好的治疗策略的关键。随着研究的不断深入,各种相关的新药和新治疗思路层出不穷,比如针对肿瘤发生及代谢过程的靶向类新药、用于辐射增敏的新的基因靶点等都已进入研究者的视线。另外,近年来关于肿瘤细胞中药物转运蛋白的研究也为综合治疗靶点寻找提供了一定依据。本文根据当前研究现状,着重总结近年来放化疗综合治疗靶向研究在上述几方面的一些新进展。 相似文献
40.