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51.
合成了文题所述的十三个手性液晶化合物。经元素分析和红外光谱分析确证了其结构,并进行了相态、相变温度和电滞回线的测定,证实其为铁电液晶。 相似文献
52.
不同类型高危儿早期干预的临床研究 总被引:4,自引:0,他引:4
目的 探索早期干预对窒息、高胆、早产三类高危儿智力发育改善的效果,寻找更合适的早期干预措施。方法 将三类高危儿分为干预组及对照组,同时随机选取正常对照组进行随访。干预组采用鲍秀兰教授“0~3岁”早期干预方案训练,各组均在6个月、1岁时分别采用婴幼儿智能发育量表(CDCC)进行智力发育测评,结果用MDI、PDI表示。结果 (1)6个月龄时MDI各干预组与对照组间有显著性差异,窒息组、早产组与正常组间亦有显著性差异;高胆组与正常组间无差异;PDI窒息组中干预组与对照组之间有显著差异(P<0.01),高胆组、早产组均无差异(P>0.05)。(2)1岁时MDI和PDI结果一致,干预组与对照组间比较窒息组、高胆组有显著差异,早产组无差异;窒息组、高胆组干预组与正常组比较无差异,对照组和早产组与正常组比较均有显著差异(P<0.01)。(3)所有干预组测评分值均高于对照组,6个月与1岁之间比较有显著差异,各观察组间比较有显著性差异(P<0.01)。结论 三类高危儿早期干预效果差异较大,干预组均较对照组分值高,早期干预有改善智力发育的作用;三类高危儿中,窒息组、高胆组效果最好,均达到或超过正常水平。所有未干预组均不及正常水平;早期干预对足月高危儿效果显著,对早产儿欠佳,远期效果尚需进一步随访观察。 相似文献
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55.
In myoelectrically operated prosthetic systems control performance decreases with an increasing number of possible movements.
A test has been designed that allows quantification of two related qualities of performance. A predefined amount of training
was given to 40 nondisabled volunteers without previous prosthetic experience. After training they attempted the test. The
two parameters measured were the response time and the control accuracy corresponding to the different movements. It is concluded
that even with a very limited amount of training fairly complex control systems can be operated with acceptable performance. 相似文献
56.
农村公共卫生投融资机制存在的问题及对策 总被引:1,自引:0,他引:1
宁德斌 《中国卫生质量管理》2007,14(5):63-66
当前,农村公共卫生投融资规模不能适应农村居民的卫生服务需要,投融资结构不合理,致使投融资效果不佳,不利于农村卫生事业的发展。为此,需要从四个方面改革农村公共卫生投融资机制:一是要建立健全国家财政投资保障制度,发挥财政在农村公共卫生投资中的主体作用;二是要改革运行模式,拓宽融资渠道;三是要改善投资结构,优化资源配置;四是要创新管理体制,提高农村公共卫生服务能力。 相似文献
57.
目的:考察新药依西美坦片在3种不同介质中的溶出特性,以研究影响其口服吸收速率的主要因素和规律。方法:建立HPLC法检测其制剂含量和溶出液浓度,色谱柱:HypersilC18(150mm×4.6mm,5μm);流动相:甲醇:0.05mol/LKH2PO4溶液(60:40);检测波长:247nm。溶出介质选用水、0.1mol/L盐酸溶液及0.5%十二烷基硫酸钠溶液,采用转篮法,转速100r/min。结果:依西美坦片在水和0.1mol/L盐酸溶液中的溶出较差,在0.5%十二烷基硫酸钠溶液巾溶出迅速完全,60min时在3种介质中的溶出百分率分别为(60.25±3.76)%、(47.57±1.20)%和(82.24±0.96)%。结论:依西美坦片可能主要在肠道溶出,其溶出速率受介质影响大。 相似文献
58.
The effect of laser refractive surgery on the on-field performance of professional baseball players.
BACKGROUND: The aim of this study was to determine the effect of laser refractive surgery on the offensive performance of professional baseball players. METHODS: Extensive search of the public media was conducted to determine which major league baseball players had undergone laser refractive surgery and when the procedure was performed. Baseball performance data were then used to determine presurgery and postsurgery baseball performance averages. A total of 17 position players were identified; however, 5 of these players were not considered in the analysis owing to insufficient playing experience either before or after the laser procedure. RESULTS: No statistically significant or practically significant difference was found between the presurgery and postsurgery means on either on-base percentage (P = 0.31), batting average (P = 0.39), slugging percentage (P = 0.66) or on-base plus slugging (OPS; P = 0.997) of major league baseball players. CONCLUSIONS: These preliminary findings suggest that professional baseball players should not expect a laser refractive surgical procedure to significantly improve their offensive baseball performance, despite the elimination of glasses or contact lens wear. 相似文献
59.
Tourette syndrome and neuropsychological performance 总被引:3,自引:0,他引:3
R A Bornstein G B Baker T Bazylewich A B Douglass 《Acta psychiatrica Scandinavica》1991,84(3):212-216
This study examined performance on a battery of neuropsychological tests in a sample of 28 patients with Tourette's syndrome (TS). Test scores were converted to age-corrected T-scores to control for the effect of age on test performance. The frequency of abnormal test performances was variable, but more frequent on motor and sensory tasks. Symptom severity as measured by the Tourette Syndrome Global Scale was inversely related to neuropsychological performance. In general, neuropsychological performance was mildly below average. The pattern of performance was similar to previous studies of TS patients. 相似文献
60.
Beth Hoskins Dudley F. Peeler Kathia Lawson Angie M. Barnes Ing K. Ho 《Brain research bulletin》1991,27(2):279-281
The effects of haloperidol on motor and functioning and cognitive functioning were studied in young (3-5 months old) and aged (20-22 months old) male mice by examining haloperidol-induced catalepsy and haloperidol-induced decrements in performance on a radial arm maze. The aged mice were much more sensitive to these adverse effects of haloperidol than were the young mice. Studies of the distribution of radioactivity from [3H]haloperidol to the brain indicated that the differences in sensitivity to this drug were not due to pharmacokinetic differences. The results demonstrate that mice are suitable for studies of aging-induced changes in the behavioral effects of neuroleptic agents. 相似文献