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1.
Studies have been made of the effect of stimulation of the anterior and posterior hypothalamus on the electrical activity of the hemispheres, arterial blood pressure, heart and respiration rates. Mainly desynchronizing mechanisms were revealed in the ascending influences from both the anterior and posterior hypothalamus. Concerning the descending influences, it was found that stimulation of the anterior hypothalamus evokes depressor reactions, whereas stimulation of the posterior hypothalamus results in pressor reactions. Peculiarities of evolutionary development of the ascending and descending mechanisms of the posterior and anterior hypothalamus are discussed.  相似文献   
2.
Reconstructions of the human-African great ape phylogeny by using mitochondrial DNA (mtDNA) have been subject to considerable debate. One confounding factor may be the lack of data on intraspecific variation. To test this hypothesis, we examined the effect of intraspecific mtDNA diversity on the phylogenetic reconstruction of another Plio- Pleistocene radiation of higher primates, the fascicularis group of macaque (Macaca) monkey species. Fifteen endonucleases were used to identify 10 haplotypes of 40-47 restriction sites in M. mulatta, which were compared with similar data for the other members of this species group. Interpopulational, intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of divergence time and branching order incorporating this variation were substantially different from those based on single representatives of each species. We conclude that intraspecific mtDNA diversity is substantial in at least some primate species. Consequently, without prior information on the extent of genetic diversity within a particular species, intraspecific variation must be assessed and accounted for when reconstructing primate phylogenies. Further, we question the reliability of hominoid mtDNA phylogenies, based as they are on one or a few representatives of each species, in an already depauperate superfamily of primates.   相似文献   
3.
The 60 kb plasmid pCL1 isolated from Bacillus sp. 62 confers antibacterial activity. Bacteria cured from pCL1 by ethidium bromide treatment loose the sign. Transformation of cured from by pCL1 restores the initial phenotype, while plasmid transfer into B. subtilis 168 does not confer antibacterial activity, which indicates the significance of chromosome locuses in the formation of this sign.  相似文献   
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Microiontophoretic local injection of horseradish peroxidase (HP) have been performed into the median center (MC). Many thalamic nuclei are sources of projections into MC, though the role of each nucleus is not equivalent. MC is predominantly connected with nonspecific formations (reticular, parafascicular, central-lateral, paracentral, ventromedial, paraventricular). Among them the reticular nucleus is distinguished, it sends its efferent fibers from the ventral, ventrolateral and lateral areas. In the anterior part of the reticular nucleus there are no HP-labelled cells. In MC little projections from specific nuclei (ventrobasal complex, ventrolateral nucleus, geniculate body) are presented, as well as simple projections from the associative nuclei. The data obtained are in keeping with electron physiological investigations.  相似文献   
9.

Background

A public that is an informed partner in clinical research is important for ethical, methodological, and operational reasons. There are indications that the public is unaware or misinformed, and not sufficiently engaged in clinical research but studies on the topic are lacking. PARTAKE – Public Awareness of Research for Therapeutic Advancements through Knowledge and Empowerment is a program aimed at increasing public awareness and partnership in clinical research. The PARTAKE Survey is a component of the program.

Objective

To study public knowledge and perceptions of clinical research.

Methods

A 40-item questionnaire combining multiple-choice and open-ended questions was administered to 175 English- or Hindi-speaking individuals in 8 public locations representing various socioeconomic strata in New Delhi, India.

Results

Interviewees were 18–84 old (mean: 39.6, SD±16.6), 23.6% female, 68.6% employed, 7.3% illiterate, 26.3% had heard of research, 2.9% had participated and 58.9% expressed willingness to participate in clinical research. The following perceptions were reported (% true/% false/% not aware): ‘research benefits society’ (94.1%/3.5%/2.3%), ‘the government protects against unethical clinical research’ (56.7%/26.3%/16.9%), ‘research hospitals provide better care’ (67.2%/8.7%/23.9%), ‘confidentiality is adequately protected’ (54.1%/12.3%/33.5%), ‘participation in research is voluntary’ (85.3%/5.8%/8.7%); ‘participants treated like ‘guinea pigs’’ (20.7%/53.2%/26.0%), and ‘compensation for participation is adequate’ (24.7%/12.9%/62.3%).

Conclusions

Results suggest the Indian public is aware of some key features of clinical research (e.g., purpose, value, voluntary nature of participation), and supports clinical research in general but is unaware of other key features (e.g., compensation, confidentiality, protection of human participants) and exhibits some distrust in the conduct and reporting of clinical trials. Larger, cross-cultural surveys are required to inform educational programs addressing these issues.  相似文献   
10.
In rats, single pulse activity of inter- and motoneurons of the spinal cord lumbar segment was studied in stimulation of cut. n. ischiadicus, extensor (n. gastrocnemius) and flexor (n. peroneus communis) after treatment with the Viper raddei venom for 4 weeks. In the control rats, no responses occurred in the n. ischiadicus distal stump, whereas the responses to contralateral nerve stimulation did occur. On the intact side, the responses occurred in opposite sequence. The absence of effects of the cut nerve distal stump stimulation in control rats resulted from the coalescence absence in the proximal stump which suggests atrophy of the distal stump. Morphological data prove a distal stump hypertrophy and restoration of the affected limb motor activity. The findings suggest a possibility of application of the Viper raddei venom for regeneration of injured peripheral nerve.  相似文献   
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