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41.
幼儿第二语言(外语)获得成效之多因素研究   总被引:6,自引:0,他引:6  
【目的】 从语言和认知发展的角度研究幼儿第二语言的获得,探讨童学习外语的成效。【方法】 选择18~24个月、3-6岁正常幼儿,评价儿童的一般情况、语言发育水平(幼儿语言筛查表,WPPSI语言部分和PPVT)、中文和英文的语音分辨测验、英文发音准确性、记忆能力和英文学习成绩。研究的第一阶段为语音输入,18~24个月幼儿被分为两组,分别给予100h的中文和英文的语音输入。第二阶段,所有儿童参加14周的英语教学和测验。【结果】 70.9%儿童的家长重视学英文,高于重视中文获得的比例。是否经常听儿童磁带与中文词汇量有显著的正相关。英语成绩:女孩显著高于男孩;与年龄、中文和英文的语音分辨能力、WPPSI语言和PPVT的原始分、记忆能力呈显著的正相关。英语发音的准确性与年龄和中文语音分辨能力有显著的正相关。【结论】 幼儿学习L2:①应充分重视母语的发展;②无需从幼儿早期开始,在学龄前学习成效随年龄而提高;③女童的语言能力强于男童。④语音训练应考虑年龄和方法。  相似文献   
42.
OBJECTIVES: To investigate doctors' and nurses' attitudes toward 14 potential prioritization criteria. METHODS: This study was performed by using the random paired scenario method. The respondents received a questionnaire with 12 pairs of scenarios, imaginary patient cases, each of which contained two to three different prioritization criteria (e.g., child, old patient, poor patient). Respondents were asked which one of each scenario pair they would choose if only one patient could be treated. The scenarios were randomly put into 30 different questionnaire sets. There was a random selection of 241 doctors and 151 nurses in Finland, with response rates of 60.3% and 50.3%, respectively. RESULTS: Doctors prioritized young patients, severe disease, expensive treatments and posteriorized (negatively prioritized) demented or institutionalized patients, and patients having a self-caused disease. Children were strongly prioritized, even over serious diseases. Expensive treatments appeared to be favored by doctors, and this result cannot be explained by severity of disease. Nurses' attitudes were similar to those of doctors. CONCLUSIONS: Children were strongly prioritized. Elderly persons were posteriorized if they had dementia or were living in institutions. Patients having a self-caused disease are posteriorized, more often by nurses than by doctors.  相似文献   
43.
The relationship between time and the post-traumatic metabolic response was studied in a commonly used experimental model of trauma. Twenty nine rats underwent laparotomy and jugular vein sham catheterization as the standard trauma. The rats were fed ad libitum and compared to pair fed controls in terms of nitrogen balance and liver protein synthesis. The pairs of rats were divided into three groups according to the duration of the experiment, which was 24 h, 48 h or 72 h. The nitrogen balance was calculated daily and the liver protein synthesis in vitro measured in 10 rats after 48 h with an asanguinous perfusion system using L-(1-C(14))-Leucine. The metabolic effect of trauma was first detected in liver protein synthesis, which was diminished in the early post-traumatic period (percentage synthesis rates: post-traumatic 34.6 +/- 10.7 and pair fed 60.4 +/- 21.3, Mean +/- SD, P < 0.05). During this period the whole body nitrogen balances were similar (post-traumatic -1.200 +/- 1.440 and pair fed -0.880 +/- 1.130, gN/kg/48 h, mean +/- SD). On the third day, the response to nitrogen intake and the nitrogen balance became significantly worse in the post-traumatic rats (post-traumatic 0.214 +/- 1.680 and pair fed 1.236 +/- 1.220, gN/kg/day, mean +/- SD). These observations suggest that, firstly, the 'flow' phase has its onset on the third post-trauma day, and secondly that trauma does decrease liver protein synthesis, and this decrease lasts at least through the 'ebb' phase. The results indicate the necessity of defining the metabolic phase in experimental studies of post-traumatic metabolism.  相似文献   
44.
徐浩  丁勇 《现代医院》2002,2(3):49-50
<正> 暨南大学医学院第一附属医院,又名广州华侨医院,经过20年的发展已成为一所集医、教、研为一体的大型三级甲等医院。医院的科研发展始终坚持"以学科建设为基础,人才培养是关键"的科研办院思路,从建院初期以调入人才为主到目前的以人才引进为辅、培养人才为主,20年来培养了一批中青年学术带头人,形成了一批技术力量强大的学科群。从建院初期仅有眼科学、内科学(血液病专业)2个硕士学位授与点发展到现在拥有眼科学、内科学、妇产科学3个博士学位、14个硕士学位授权点,1998年还被国家教委批准为临床医学专业学位授与点的试点单位。在各类学术期刊上发表文章3089篇,主编及参与编写171部专著,承担各级科研课题695项,获国家科技进步奖1项,省部级成果奖25项,厅局级科技进步奖69项,获专利9项。医院在培育科研优势的同时更注意发挥学科优势促进学科的发展。  相似文献   
45.
Randomized Controlled Trial of Back School With and Without Peer Support   总被引:1,自引:0,他引:1  
The aim of this trial was to determine whether social interaction between patients with long-lasting nonspecific back pain reduces subjective or objective disability. The participants were selected from persons visiting an occupational health care unit because of back pain. After a clinical examination in a university clinic, subjects without a specific diagnosis and having no disabilities preventing active rehabilitation were selected for study. The subjects (n = 108) were randomized into treatment (n = 54) and control groups (n = 54). Altogether 18 study groups, 9 treatment groups and 9 groups for controls, were formed. Before starting the back schools altogether 15 subjects dropped out. Both the treatment groups (n = 47) and the controls (n = 46) attended a back school consisting of 10 lessons and demonstrations supervised by a physiotherapist. The participants in treatment groups, but not the controls, had physical exercise and social intercourse with other members within the group. The clinical examination was repeated after 6 and 12 months. Both the treatment groups and the controls showed improvement in perceived functional capacity (assessed with Oswestry disability questionnaire) and in perceived life quality (assessed with 15D score). At the 6-month follow-up life quality had improved statistically significantly more among the participants in treatment groups than among the controls, and at the 12-month follow-up the Oswestry index showed corresponding improvement. Among subjects suffering from nonspecific back pain, social support improves the results of active rehabilitation.  相似文献   
46.
Effects of ergonomic intervention in work with video display units   总被引:8,自引:0,他引:8  
OBJECTIVES: This study evaluated the effect of an intensive ergonomic approach and education on workstation changes and musculoskeletal disorders among workers who used a video display unit (VDU). METHODS: A randomized controlled design was used. The subjects (N=124) were allocated into three groups (intensive ergonomics, ergonomic education, reference) using stratified random sampling. The evaluation involved questionnaires, a diary of discomfort, measurements of workload, and an ergonomic rating of the workstations. The assessments were made 2 weeks before the intervention and after 2 and 10 months of follow-up. RESULTS: The intensive and training groups showed less musculoskeletal discomfort than the reference group after 2 months of follow-up. Positive effects on discomfort were seen primarily for the shoulder, neck, and upper back areas. No significant differences were found for the strain levels or prevalence of pain. After the intervention the ergonomic level was distinctly higher in the intensive ergonomic group than in the education or reference group. CONCLUSIONS: Both the intensive ergonomics approach and education in ergonomics help reduce discomfort in VDU work. In attempts to improve the physical ergonomics of VDU workstations, the best result will be achieved with cooperative planning in which both workers and practitioners are actively involved.  相似文献   
47.
BACKGROUND: Work-related mortality is a relatively new concept which aims to widen occupational health and safety; to take into account not only recognized fatal occupational accidents and diseases but also other work-related deaths. Few countries in the world have a register for work-related diseases. METHODS: Estimates are calculated using baseline world mortality scenarios of all diseases for the year 2000 and attributable fractions made for work-related diseases in Finland, as adjusted. RESULTS: It is estimated that about 2 million work-related deaths take place annually. Men suffer two thirds of those deaths. The biggest groups of work-related diseases are cancers, circulatory diseases and communicable diseases. CONCLUSIONS: Information about work-related diseases is needed for prevention, as people in developed countries are working longer, and the age of retirement is being raised in many countries. As a result, workers are being exposed to different kinds of substances and working conditions for a longer time. In developing countries, work exposures may already start in infancy. Due to industrialization, workers in developing countries are facing new conditions with a lack of relevant knowledge and skills. With the help of information, nations can direct resources and skills for appropriate purposes such as regulatory measures on health and safety at work.  相似文献   
48.
OBJECTIVE: To characterise those surgical patients who consume one half of all hospital patient days, and to compare their outcome with that of low consumers. DESIGN: A retrospective cohort study. SETTING: Tertiary referral centre, Finland. PATIENTS: 13025 surgical patients who were admitted to a university hospital in Kuopio, Finland, during 1997. INTERVENTIONS: The length of stay below which half of all patient days fell was chosen as a cut-off value to divide patients into low and high consumers. MAIN OUTCOME MEASURES: Hospital and 12-month mortality and standardised mortality ratios (SMR: observed deaths/expected deaths based on the corresponding general population). RESULTS: The 2239 patients (17%) whose length of stay exceeded 9 days (high consumers) took up one half of all patient days. The pattern of resource use varied between operative specialities. At 12 months the SMRs showed excess mortality among high consumers (5.0, 95% confidence interval 4.4 to 5.7) compared with low consumers (2.1, 95% CI 1.9 to 2.3). CONCLUSIONS: Relating the length of stay to the proportion of resources consumed may provide a feasible tool for the recognition of different patterns of use of resources. SMRs may be more relevant measures of outcome than hospital mortality when assessing the efficacy of operative treatment.  相似文献   
49.
The pressure pain threshold for the upper trapezius and levator scapulae muscles was studied in a working population with a mechanical algometer. The lower 95% confidence interval limits of the correlation coefficient describing intraobserver reliability varied from 0.71 to 0.92, measured in 93 men and 70 women. The values describing interobserver reliability varied from 0.68 to 0.79, measured only in men. The day-to-day repeatability was measured in 10 women and it proved to be acceptable. In general, women had lower pain threshold values than men. Low values were related to complaints in the neck and shoulder region. However, the values in the non-symptomatic population displayed wide variation. Though unsuited for use as a primary diagnostic or screening tool, the method shows promise for application in individual follow-up studies as an outcome measure in therapeutic trials.  相似文献   
50.
In the awake, normal subject, infusions of branched chain amino acids (BCAA) alter the ventilatory response to CO2. If this effect extends to the sleep state, it could contribute to our understanding of the neurophysiology of the sleep state as well as having clinical utility in ameliorating or preventing apnea syndromes. This study examined the effect of nocturnal BCAA infusion on sleep patterns (as measured by EEG, chest wall motion, Sao2 and end-tidal CO2) in five normal male subjects. Subjects were monitored with a polysomnograph from 21.00 to 7.00. Each subject was studied double-blind in random order on three occasions: a) baseline, no infusion (B); b) control, with normal saline infusion (S); and c) treatment, infusion of BCAA (BCAA). Sleep pattern analysis did not demonstrate any measurable effect of the BCAA infusion. End-tidal CO2 levels during BCAA infusion were lower than during baseline or control nights (mean +/- s.d.; BCAA: 5.8 +/- 0.7 kPa vs. B: 6.9 +/- 0.1 kPa, P less than 0.01 and S: 6.7 +/- 0.4 kPa, P less than 0.05). This study demonstrates that nocturnal BCAA infusions have effects on respiratory control during sleep; further clinical studies are required to determine whether these data have implications for disease states.  相似文献   
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