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101.
英语阅读障碍儿童词汇命名加工特征的研究   总被引:1,自引:1,他引:0  
目的研究英语阅读障碍儿童操作英语词汇的相关能力 ,探索英语阅读障碍的表现特点与矫治的手段。方法英语真、假词命名实验 ,观察 3 4名阅读障碍儿童和 3 4名对照组儿童的实验结果。结果 ( 1)障碍组右视野在真、假词的命名时间上与对照组存在显著差异 ;( 2 )障碍组在真词和假词上的命名错误率均大于正常组 ,假词命名的错误率大幅增加。 ( 3 )障碍组右视野的真词命名时间明显长于左视野 ,假词命名的错误率也明显大于左视野。结论英语阅读障碍的儿童显示出了操作英语语音能力的欠缺以及左测大脑半球活动水平不足的倾向。  相似文献   
102.
Three recent sequential methods, group sequential analysis (GSA), the sequential probability ratio test (SPRT) and the triangular test (TT) are well suited to randomized clinical trials with a censored response criterion, as they do not require matched pairs of patients. We undertook a simulation study to investigate their statistical properties and to compare these three methods with the fixed-sample design. Our results suggest that the three methods have the expected statistical properties for size and power; they allow an important reduction of the average number of events before stopping, except with GSA when there is no treatment difference; the triangular test (closed design) appears the optimal design, as the variance of the number of events is smaller than with the sequential probability ratio test (open design) and analysis after every twenty new events does not alter the statistical properties of these sequential methods and enhances their usefulness.  相似文献   
103.
Risk Factors for a First Febrile Seizure: A Matched Case-Control Study   总被引:10,自引:6,他引:4  
Summary We conducted a matched casecontrol study to identify risk factors for first febrile seizures, with special emphasis on characteristics of the acute illness episode. Cases were identified through hospital emergency departments; controls were identified through outpatient clinics and emergency departments. Sixtynine children with first febrile seizures and no history of previous unprovoked seizures were matched for age (±6 months), site of routine pediatric care, and date of visit (±weeks) with 1 or 2 febrile controls who had no history of previous febrile or unprovoked seizures. Medical records for the index visit were reviewed, and parents were interviewed by telephone. Illness characteristics examined included height of temperature, type of underlying illness, contact with a physician during the illness but before the index visit, and use of acetaminophen or decongestants. Family history of febrile and of unprovoked seizures, sociodemographic characteristics, daycare use, and selected preand perinatal variables were also studied. On multivariable analysis, significant independent risk factors were height of temperature, history of febrile seizures in a firstor in a higher degree relative. Gastroenteritis as the underlying illness had a significant inverse (i.e., protective) association with febrile seizures. Maternal smoking during pregnancy was a marginally significant predictor of febrile seizures.  相似文献   
104.
105.
Neonatal autopsy findings are valuable additions to the information base for current cases and future perinatal care, so the reported decline in the autopsy rate is disturbing. In order to estimate the prevalence of the neonatal autopsy among a large population of deaths, we surveyed participating institutions of the Study Group for Complications of Perinatal Care. Investigators from 37 neonatal intensive care units, located in 9 children's hospitals, 4 hospitals for women and infants, and 24 full-service pediatric and adult care hospitals, reported their neonatal death and autopsy rates for 1989. The overall neonatal autopsy rate was 51% among 1645 neonatal deaths. The rate was variable, ranging from 22 to 100%. We found the neonatal autopsy rate to be lower than previously reported and not apparently influenced by the type of center or by the type of medical staff at the centers. In order to assess and potentially reverse the current low rate, the influence of neonatal demographic and clinical factors, as well as physician-related factors, must be studied.  相似文献   
106.
Reflection on the geographic distribution of multiple sclerosis in France   总被引:1,自引:0,他引:1  
The geographic distribution of multiple sclerosis within the 95 Départements and the 21 Régions of France was defined from a 1986 nationwide prevalence series derived from questionnaires. This indicated a significant clustering of high frequency regions in the northeastern part of the country with most significantly low areas in the south and west. Distributions were similar to those for MS death rates by Département and Région for 1968–1977, indicating geographic stability over time; but there was also evidence of diffusion over time. The 1986 prevalence distribution was also compared with all published prevalence rates for communities of France. From all these resources we conclude that all of France falls within the "high frequency zone" for MS, that the nationwide prevalence rate is at least 50 per 100000 population, and that there is evidence of geographic clustering of the disease with temporal spread of the cluster.  相似文献   
107.
Relocation mortality has been cited as an important factor when considering the placement of elderly patients. This study describes the fate of dementia patients relocated to facilitate the move to a new hospital. Some wards were moved as intact units—that is, the patients were kept together and there was little change in the nursing or medical staff. Two other wards were closed, and these patients were dispersed to several existing and new wards and experienced changes of nursing and medical staff. All patients underwent prerelocation and postrelocation orientation programmes. The mortality figures for the total patient group before and after the relocation do not show any statistically significant increase in mortality postrelocation. However, for wards that were closed and where the patients suffered maximum disruption to patient group and nursing staff, there was a significant increase in mortality rates.  相似文献   
108.
Proportionate cancer mortality was analyzed among white male carpet and textile workers in five northwest Georgia counties for the years 1970-1984. Compared with other Georgians, carpet and textile workers had higher proportions of lymphocytic leukemia (proportionate cancer mortality ratio [PCMR] = 2.9; 95% CI = 1.4-5.4]) and testicular cancer (PCMR = 3.2; 95% CI = 1.0-7.5). The excess mortality from lymphocytic leukemia was even higher when the analysis was limited to workers deemed most likely to work directly in production areas (PCMR = 4.2; 95% CI = 1.7-8.7). Further studies are needed to determine if the observed excesses are the result of workplace exposures.  相似文献   
109.
在筛检肿瘤高危险人群过程中,应用标化比例死亡比(SPMR)的分析方法,研究了两个工厂全肿瘤和肺癌的发生状况,并用标化死亡比(SMR)的方法验证SPMR的结论。结果表明,两种方法分析结果均一致性显示全肿瘤和肺癌在两工厂中的死亡率显著高于当地居民。由于SPMR分析资料极易获得,分析方法又较SMR简便易行,适用于基层实际工作中对各种疾病死亡状况进行病因学分析。  相似文献   
110.
本文提出以紫外分光光度法测定增效黄连素胶囊含量。样品经乙醇溶解、水稀释后,不经分离提取,直接在346nm波长处测定盐酸黄连素;在346nm和271nm波长处以系数倍率法测定甲氧苄氨嘧啶,测得二组分的平均回收率分别为99.1%和99.6%,相对标准偏差为0.67%和0.82%(n=9).本法简便,快速,适用于增效黄连素胶囊的常规分析.  相似文献   
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