首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
  示例: 沙坡头地区,人工植被区,变化  检索词用空格隔开表示必须包含全部检索词,用“,”隔开表示只需满足任一检索词即可!
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1043篇
  免费   3篇
管理学   35篇
民族学   58篇
人才学   1篇
人口学   131篇
丛书文集   22篇
理论方法论   201篇
综合类   101篇
社会学   429篇
统计学   68篇
  2014年   5篇
  2013年   4篇
  2012年   135篇
  2011年   86篇
  2010年   31篇
  2009年   10篇
  2008年   57篇
  2007年   48篇
  2006年   54篇
  2005年   33篇
  2004年   30篇
  2003年   21篇
  2002年   32篇
  2001年   18篇
  2000年   22篇
  1999年   13篇
  1998年   14篇
  1997年   11篇
  1996年   12篇
  1995年   13篇
  1994年   12篇
  1993年   21篇
  1992年   18篇
  1991年   26篇
  1990年   6篇
  1989年   21篇
  1988年   35篇
  1987年   26篇
  1986年   19篇
  1985年   22篇
  1984年   17篇
  1983年   30篇
  1982年   25篇
  1981年   28篇
  1980年   24篇
  1979年   12篇
  1978年   9篇
  1977年   8篇
  1976年   6篇
  1974年   3篇
  1973年   2篇
  1972年   2篇
  1971年   3篇
  1970年   3篇
  1969年   3篇
  1959年   1篇
  1957年   3篇
  1955年   4篇
  1950年   1篇
  1948年   2篇
排序方式: 共有1046条查询结果,搜索用时 15 毫秒
51.
In order to achieve the intended impact on a community, comprehensive community initiatives must sustain programs once they have been implemented. However, planning for sustainability is challenging and is rarely incorporated in the planning process of an initiative. The current study examined 19 5-year plans developed during the planning phase of the Comprehensive Strategy for Serious, Violent and Chronic Juvenile Offenders. Quantitative and qualitative methods were employed to assess the extent to which the construct of sustainability was incorporated. The plan analysis was supplemented with results from other components of the complex evaluation design implemented as part of the process evaluation of Comprehensive Strategy. Results suggested that sustainability was not accounted for during the planning phase of this initiative. The implications of these findings, including the importance of planning for sustainability in order to achieve sustainability, are discussed.  相似文献   
52.
Ovarian cancer is the leading cause of gynaecological cancer death. The mortality rate of ovarian cancer could be greatly decreased if there were a screening test which was able to detect the disease at an early stage, resulting in an increased probability of cure. The most promising prospect for the early detection of ovarian cancer comes from the rapidly advancing field of clinical proteomics. An increasing number of reports on the potential clinical application of proteomics research for early detection as well as risk assessment and management of ovarian cancer are being published. Although the research is very promising, major technical challenges are still preventing new discoveries in ovarian cancer proteomics from being translated into clinical practice.  相似文献   
53.
The Physical Activity Questionnaire for Elderly Japanese (PAQ-EJ) is a self-administered physical activity questionnaire for elderly Japanese; the authors report here on its repeatability and direct and indirect validity. Reliability was assessed by repeat administration after 1 month. Direct validation was based on accelerometer data collected every 4 s for 1 month in 147 individuals age 65-85 years. Indirect validation against a 10-item Barthel index (activities of daily living [ADL]) was completed in 3,084 individuals age 65-99 years. The test-retest coefficient was high (r = .64-.71). Total and subtotal scores for lower (transportation, housework, and labor) and higher intensity activities (exercise/sports) were significantly correlated with step counts and durations of physical activity <3 and >or=3 METs (r = .41, .28, .53), respectively. Controlling for age and ADL, scores for transportation, exercise/sports, and labor were greater in men, but women performed more housework. Sex- and ADL- or age-adjusted PAQ-EJ scores were significantly lower in older and dependent people. PAQ-EJ repeatability and validity seem comparable to those of instruments used in Western epidemiological studies.  相似文献   
54.
The lower extremity performance in elderly female patients with mild to moderate Parkinson's disease (PD; n = 12) and controls (n = 16) was compared. Isometric dynamometry and force-plate measurements were used. PD patients had lower (p < .05) bilateral (BL) maximal isometric leg-extension force (MF), BL isometric MF relative to body mass, and maximal rate of isometric force development than control participants. BL strength deficit was greater (p < .05) in PD patients than in controls. A significantly longer chair-rise time and lower maximal rate of vertical-ground-reaction-force development while rising from a chair was found in PD patients than in controls. These findings suggest that elderly women with PD have lowered voluntary isometric force-generation capacity of the leg-extensor muscles. Reduced BL leg-extension strength might contribute to the difficulty of individuals with PD to rise from a chair.  相似文献   
55.
Administrators at 68% of 4-year colleges nationwide (N = 747) responded to a survey concerning the types of programs and policies they used in response to students' heavy drinking. Most schools conducted targeted alcohol education and invested in institutional prevention efforts; half conducted social norms campaigns; a sizeable minority restricted alcohol on campus. Schools that focused on demand reduction were less likely to ban alcohol use. One in 3 schools received funding for these programs from governmental agencies, and 1 in 5 from the alcohol industry. Such schools were more likely to conduct targeted alcohol education and social norms programs and were less likely to restrict alcohol use on campus or at college events. Colleges may want to reconsider prevention initiatives that focus exclusively on demand or supply. They may also want to examine the extent to which funding is the driving force shaping the direction of their alcohol initiatives.  相似文献   
56.
Self-rated health as a predictor of mortality has been studied primarily in large, representative populations, with relatively little progress toward understanding the information processing that individuals use to arrive at these ratings. With subsamples of National Health and Nutrition Examination Survey (NHANES) Epidemiologic Follow-up Study (NHEFS) data for respondents with circulatory system disease (N = 3,709) and respondents with no diagnosable disorders (N = 1,127) at baseline, we test the idea that individuals with experience of chronic disease of the circulatory system will have more predictive self-ratings of health than healthy individuals. Poor or fair self-rated health increased the adjusted hazard of all-cause mortality for respondents with circulatory system disease, but not for respondents who were healthy. Additional analyses confirm that poor or fair self-rated health is particularly predictive for respondents with self-reported history of circulatory system diagnoses and perception of symptoms, but not for respondents without symptoms or diagnoses prior to the NHANES physical exam.  相似文献   
57.
58.
The fairplayer.manual is a school-based program to prevent bullying. The program consists of fifteen to seventeen consecutive ninety-minute lessons using cognitive-behavioral methods, methods targeting group norms and group dynamics, and discussions on moral dilemmas. Following a two-day training session, teachers, together with skilled fairplayer.teamers, implement fairplayer.manual in the classroom during regular school lessons. This chapter offers a summary of the program's conception and underlying prevention theory and summarizes the results from two evaluation studies. Standardized questionnaires showed a positive impact of the intervention program on several outcome variables.  相似文献   
59.
In competitive swimming, suits have become more important. These suits influence friction, pressure and wave drag. Friction drag is related to the surface properties whereas both pressure and wave drag are greatly influenced by body shape. To find a relationship between the body shape and the drag, the anthropometry of several world class female swimmers wearing different suits was accurately defined using a 3D scanner and traditional measuring methods. The 3D scans delivered more detailed information about the body shape. On the same day the swimmers did performance tests in the water with the tested suits. Afterwards the result of the performance tests and the differences found in body shape was analyzed to determine the deformation caused by a swimsuit and its effect on the swimming performance. Although the amount of data is limited because of the few test subjects, there is an indication that the deformation of the body influences the swimming performance.  相似文献   
60.
Upper extremity musculoskeletal symptoms and disorders are common in the working population. The economic and social impact of such disorders is considerable. Long-time, dynamic repetitive exposure of the hand-arm system during manual handling operations (MHO) alone or in combination with static and postural effort are recognised as causes of musculoskeletal symptoms and disorders. The assessment of these manual work tasks is crucial to estimate health risks of exposed employees. For these work tasks, a new method for the assessment of the working conditions was developed and a validation study was performed. The results suggest satisfying criterion validity and moderate objectivity of the KIM-MHO draft 2007. The method was modified and evaluated again. It is planned to release a new version of KIM-MHO in spring 2012.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号