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排序方式: 共有740条查询结果,搜索用时 15 毫秒
731.
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734.
Peroral administration of 70 mg/kg ascovertin and 150 mg/kg Leuzea extract to rats with cerebral ischemia for 5 days prevented destructive changes and decrease in the density of synapses in the cerebral cortex. These preparations activated compensatory and reparative mechanisms underlying plasticity of the synaptic pool, which was realized through hypertrophy and destruction of synaptic contacts. Ascovertin possessed more pronounced cerebroprotective activity than Leuzea extract.  相似文献   
735.
The Trait-based test that uses the Extended Simes procedure (TATES) was developed as a method for conducting multivariate GWAS for correlated phenotypes whose underlying genetic architecture is complex. In this paper, we provide a brief methodological critique of the TATES method using simulated examples and a mathematical proof. Our simulated examples using correlated phenotypes show that the Type I error rate is higher than expected, and that more TATES p values fall outside of the confidence interval relative to expectation. Thus the method may result in systematic inflation when used with correlated phenotypes. In a mathematical proof we further demonstrate that the distribution of TATES p values deviates from expectation in a manner indicative of inflation. Our findings indicate the need for caution when using TATES for multivariate GWAS of correlated phenotypes.  相似文献   
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737.
Neuroscience and Behavioral Physiology - Objectives. To assess the diagnostic value of NR2 peptide as a biomarker for cerebral ischemia by studying its plasma concentration in patients with...  相似文献   
738.
Causes of urinary incontinence in males are discussed. Various artificial sphincter implantation techniques are considered. Particular attention is focused on some models of the Scott artificial urinary sphincter. The main requirements for the implantable device and its application are discussed. The construction of the first domestic sphincter A-1 is described.  相似文献   
739.
Schuening  FG; Storb  R; Stead  RB; Goehle  S; Nash  R; Miller  AD 《Blood》1989,74(1):152-155
Amphotropic helper-free retroviral vectors containing either the bacterial neomycin phosphotransferase gene (NEO) or a mutant dihydrofolate reductase gene (DHFR*) were used to infect canine hematopoietic progenitor cells. In previous experiments, successful transfer and expression of both genes in canine CFU-GM were achieved after 24-hour cocultivation with virus-producing cells. The average rate of gene expression was 10% (6% to 16%) as measured by the number of CFU-GM resistant to either the aminoglycoside G418 or methotrexate. In an attempt to increase the efficiency of gene transfer, marrow was cocultured for 24 hours with either NEO or DHFR* virus-producing packaging cells and then kept in long-term marrow culture fed three times with virus-containing supernatant (2 to 5 x 10(6) CFU/mL). After six days, cells were harvested and cultured in CFU-GM assay with and without a selective agent. The average rate of gene expression in CFU- GM in five independent experiments was 46% and ranged from 19% to 87%. In conclusion, the efficiency of gene transfer into canine hematopoietic progenitor cells has been increased fourfold by combining cocultivation with long-term marrow culture as compared with results obtained with cocultivation only.  相似文献   
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