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91.
目的:了解新疆的维吾尔、哈萨克、汉族小学生的体格发育和运动素质水平。方法:对1995年全国学生体质与健康调研资料进行比较分析。结果:汉族身高发育居优势,体格水平高,但运动素质起始水平低;维吾尔族体格发育水平相对低,身体充实度等提高,但肌力和柔韧性展现明显优势;哈萨克族体重水平最高,身体充实度高,速度、爆发力和耐力素质表现优异,但肌力和柔韧性素质表现较差。结论:应继续发挥这些民族学生的体质优势,努力改善其体格和运动素质方面的某些不足。  相似文献   
92.
在我国中等发达及上农村地区,大病统筹合作医疗或医疗保险以其可缓解农村居民的就医经济风险而受到欢迎,但是在方案的拟订过程中尚存在一些明显的技术缺陷,比如,“大病”的技术定义、农村居民就医经济风险分析、风险临界线界定、保险经付比测算和保险费率厘定等,这些技术的缺乏,已严重影响农村合作医疗或医疗保险的推广和实施效果。  相似文献   
93.
鼻咽癌放射治疗后听力的变化   总被引:1,自引:0,他引:1  
目的 探讨鼻咽癌患者放疗前后听力的变化。方法 对63例鼻咽癌患者放疗前后采用纯音测听检测听觉功能。结果 鼻咽癌初次放疗对内耳感音功能无明显影响,对中耳传音功能有明显的改善作用。结论 鼻咽癌所致听力下降通过放疗可使听力得以不同程度的恢复。  相似文献   
94.
关于综合能力培养的几个问题   总被引:5,自引:1,他引:5       下载免费PDF全文
围绕学科建设和成才,指出成才、成功的几个宏观条件及其相互关系;要形成正确的世界观与价值取向;要不断提高人们的素质与思想境界,这与学术水平的提高是相辅相成的;要按照学习—实践—思考—提高的过程提高学术水平;重点学科建设的新思路:学科研究方向是学科发展的根本,学科带头人是学科发展的关键,学科关键的实验设备是学科发展的保障。  相似文献   
95.
A number of studies have reported that most individuals with autism have difficulty in attributing mental states. The primary aim of the present study was to compare the ability of children with autism to refer to knowledge states with that of mainstream school children and children with Down's syndrome. The second aim was to investigate the role of verbal mental age in referring to knowledge states. The third aim was to compare the ease with which the children referred to their own mental state and to that of others. The results suggest that some individuals with autism are able to attribute knowledge to themselves and others but that they need to have higher verbal skills than is necessary in normal individuals. The level of language skill predicted the performance of the individuals with autism, but not that of the children in the other groups. There was no good evidence that referring to one's own mental states was easier than referring to another person's, a finding which supports representational theory rather than the simulationist position.  相似文献   
96.
Association of Helicobacter pylori Infection with Gastric Adenocarcinoma   总被引:2,自引:0,他引:2  
Gastric adenocarcinoma is the most prevalent cancer in South Korea, and Helicobacter pylori (H. pylori) infection is also common. This study was performed to examine the association between H. pylori infection and gastric cancer, taking into account various other factors. To investigate the association between gastric adenocarcinoma and H. pylori infection, determined by urease-positive reaction in the CLO test, a total of 175 paired specimens (175 tumor and 175 tissues adjacent to tumor) of stomach cancer patients and a total of 113 control specimens were obtained. The positive H. pylori infection rates were 78.9% (138/175) among the patients in specimens of tumor or tissues adjacent to the tumor and 41.6% (47/113) among controls in the CLO test. A positive correlation between H. pylori infection and gastric cancer was observed (age-adjusted odds ratio, 7.0; MH χ2=34.5 with P <0.0005). These data suggest that stomach cancer patients in Korea have high infection rates of H. pylori regardless of site specificity, and this infection might be causally associated with stomach cancer.  相似文献   
97.
FK317 is a member of a new class of bioreductive agents that exhibit strong cytotoxicity against various human cancer cells. The effect of FK317 was found to be stronger than that of mitomycin C (MMC), adriamycin (ADR) or cisplatin (CDDP). Alkaline elution analysis indicated that FK317 formed interstrand DNA-DNA and DNA-protein cross-links in cells. On the other hand, no DNA single-strand breaks were observed in the cells treated with FK317. In a cell-free system the deacetylated metabolites produced cross-linked DNA under reductive conditions, though FK317 itself did not form DNA-DNA cross-links. In order to elucidate the metabolic activation mechanisms, we established an FK317-resistant subline from human non-small cell lung cancer cells (Lu99) by stepwise and brief exposure (1 h) to FK317. The resistant subline (Lu99/317) showed cross-resistance to MMC and carboquone (CQ), but not to ADR or CDDP. DT-diaphorase, which is one of the activation enzymes of MMC and CQ, was deficient in Lu99/317 cells as determined by enzyme activity assay. However, the levels of NADPH:cytochrome P450 reductase, which is another activation enzyme for MMC and CQ, were comparable in resistant and parent cell lines. Treatment of the cells with dicumarol, an inhibitor of DT-diaphorase, reduced the cytotoxicity of FK317 to Lu99 cells, but not to Lu99/317 cells. These results indicate that deacetylation of FK317 is necessary for its reductive activation, and deacetylated FK317 is reduced by DT-diaphorase to form an active metabolite, which produces DNA-DNA interstrand and DNA-protein cross-links that lead to cell death.  相似文献   
98.
Induction of antitumor immunity to T-9 rat glioma by intracellular hyperthermia using functional magnetic particles was investigated. Magnetite cationic liposomes (MCLs), which have a positive surface charge, were used as heating mediators for intracellular hyperthermia. Solid T-9 glioma tissues were formed subcutaneously on both femurs of female F344 rats, and MCLs were injected via a needle only into the left solid tumors (treatment side). The rats were then divided into two groups, which received no irradiation, or irradiation for 30 min given three times at 24-h intervals with an alternating magnetic field (118 kHz, 384 Oe). On the treatment side, the tumor tissue disappeared completely in many rats exposed to the magnetic field. The tumor tissue on the opposite side also disappeared completely, even though MCLs were not injected into the right solid tumors. To examine whether a long-lasting and tumor-specific immunity could be generated, the rats that had been cured by the hyperthermia treatment were rechallenged with T-9 cells 3 months later. After a period of transient growth, all tumors disappeared. Furthermore, immuno-cytochemical assay revealed that the immune response induced by the hyperthermia treatment was mediated by both CD8+ and CD4+ T cells and accompanied by a marked augmentation of tumor-selective cytotoxic T lymphocyte activity. These results suggest that our magnetic particles are potentially effective tools for hyperthermic treatment of solid tumors, because in addition to killing of the tumor cells by heat, a host immune response is induced.  相似文献   
99.
Fluorescence in situ hybridization (FISH) analysis was applied to detect t(12;21) using two yeast artificial chromosome probes and cosmid probes covering the TEL(ETV6) and the AML1 gene to clarify the incidence of abnormality of t(12;21) in Japanese childhood acute lymphoblastic leukemia (ALL). We detected seven TEL/AML1 fusion positive patients (9.5%), all of whom were diagnosed as B-lineage ALL, among 74 childhood ALL. On the other hand, no TEL/AML1 fusion positive patients were found among 37 adult ALL. The incidence among Japanese seemed to be lower than that among other nations. Of the seven patients with the TEL/AML1 fusion, five exhibited normal karyotype, one was t(8;12)(q11;p13), i(21q) and the remaining one exhibited a near-triploid karyotype in conventional G-banding. The FISH method clearly demonstrated that all patients with the TEL/AML1 fusion had subpopulations of leukemic cells with deletion of the normal TEL allele, which is significant for understanding the progression of leukemia with t(12;21).  相似文献   
100.
The WT1 tumor suppressor gene was examined for mutations in a panel of 44 patients with myelo-dysplastic syndromes (MDS) including acute myelogenous leukemias (AML) secondary to MDS, using polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) analysis and sequencing analysis. A WT1 mutation was detected in one out of 17 cases of AML secondary to MDS. This mutation exists upstream of the zinc finger region and is predicted to produce a truncated WT1 protein lacking the zinc finger region. No mutations were detected in 27 MDS patients who had not progressed to AML. This is the first report of analysis for WT1 mutations in a large number of MDS patients, suggesting that WT1 mutations are uncommon in MDS. Abnormalities in this gene may, however, contribute to a small proportion of cases showing progression from MDS into AML.  相似文献   
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