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81.
Abstract

The purpose of the study was to determine the effects of 15, 30, and 45 min of conditioning on maximum performance and cardiorespiratory fitness variables, body composition, pulmonary function, and serum lipids. Subjects, ages 20 to 35, were 59 inmates at a California state prison. The conditioning included running and walking and was performed three days/week at approximately 85 to 90% max HR for 20 weeks. The distance covered per exercise session was approximately 1.75, 3.25, and 5.1 miles for the 15-, 30-, and 45-min groups, respectively.

Improvements in treadmill performance time. [Vdot]O2 max, max O2 pulse, diastolic blood pressure, and total skinfold fat were proportional to duration of the training session; i.e., the subjects training in the longer duration sessions showed the greater improvements. The control group showed no significant change during the same period. Compared to the control group, the 15-min group made significant reductions in resting HR, total skinfold fat, percent fat, and waist girth and increases in [Vdot]O2 max, max O2 pulse,[Vdot]E max, and treadmill performance time. Vital capacity, FEV1.0, and % FEV1.0 remained relatively unchanged in all four groups, as did serum cholesterol and triglycerides. The 45-min group improved significantly more than the 15-min group in treadmill time, [Vdot]O2 max, max O2 pulse, resting systolic and diastolic blood pressures, and percent fat. In general, comparisons between the 15- and 30-min groups and between the 30- and 45-min groups failed to yield statistically significant differences.  相似文献   
82.
Abstract

The problems of this study were to investigate the interrelationship of selected functional and body form measures, and to examine the differences between groups varying in activity levels. The volunteers for the study, 35 college women, were placed in activity groups termed “most active” and “least active” according to their response on an activity history-recall questionnaire. Functional measures included strength and flexibility. Strength was measured with a cable tensiometer and followed the procedures outlined by H. H. Clarke. Flexibility was measured using a Leighton Flexometer. Body form measures included height, weight, percent body fat, fat free body weight, specific gravity, and ponderal index. The range, mean, and standard deviation were computed for all parameters. The Pearson product-moment correlation was employed to determine interrelationships of all variables. Equality of variances among selected parameters was determined by the F test; Cochran-Cox and two sample t tests were used to determine the equality of means among selected parameters in the activity groups. Significant differences at the .05 level were found between the means of weight, fat free body weight, trunk extension flexibility, with the most active group exhibiting higher values. The least active group showed significantly greater shoulder extension flexibility, shoulder inward rotation flexibility, and ankle flexion flexibility.  相似文献   
83.
    
Clutch performance is improved performance under pressure. However, little research has examined the psychological state experienced by athletes in these situations. Therefore, this study qualitatively examined the subjective experience underlying clutch performance across a range of sports (e.g., team, individual) and standards (Olympic to recreational athletes). Sixteen athletes (Mage = 27.08 years; SD = 6.48) took part in in-depth, semi-structured interviews primarily after an exceptional performance (M = 4.38 days later; SD = 3.14). Data were analysed inductively and thematically. Clutch states involved 12 characteristics, including heightened and deliberate concentration, intense effort, and heightened awareness, which distinguished the experience of clutch from other optimal psychological states such as flow. Other characteristics, such as perceptions of control, were also reported and supported previous experimental research on clutch. These findings present in-depth qualitative insights into the psychological state underlying clutch performance, and are discussed in relation to the existing literature on optimal psychological states in sport.  相似文献   
84.
OBJECTIVE: The goal of this study was to examine the association between sexual abuse (SA) and initiation, cessation, and current cigarette smoking among a large representative adult population in France. METHOD: A random sample size of 12,256 adults (18-75 years of age) was interviewed by telephone concerning demographic variables, health practices and beliefs, and health status--for which SA and tobacco questions were included. Bivariate and multivariate analyses were conducted. RESULTS: Nearly 46% of SA survivors were current smokers compared to 34% of non-abused persons (p<.001). Survivors of SA consumed more cigarettes per day than non-abused individuals (14.5 vs. 12.4, p<.01). Survival analysis showed an increased risk of smoking initiation for respondents abused before 18 (adjusted relative hazard=1.55; p<.0001) with referent to the non-abused group. SA was not found to be a significant predictor of current smoking status among those who began smoking after the first incident of SA. Respondents who were not sexually abused were 1.8 times (95% CI, 1.12-2.99) more likely to quit smoking than people who began smoking after they were sexually abused. CONCLUSIONS: The early identification and treatment of sexually abused persons is critical to decrease smoking among adolescents and adults because of the association of SA with both smoking initiation and decreased cessation rates. It may be more difficult to detect an association between SA and current smoking due to the high rates of smoking and lower rates of quitting among the general French population.  相似文献   
85.
Background: Decades of hospital restructuring in Canada resulted in significant reductions of nursing leadership positions and altered a nursing infrastructure important for guiding patient care. The importance of acquiring nursing leadership skills to address the negative effects of restructuring is advocated by Canadian nursing bodies. Objectives: To describe a service innovation for a nursing community. The librarians of the University of Manitoba Health Sciences Libraries (UMHSL) created an online nursing leadership literature centre to support a leadership programme launched by the Nursing Leadership Council (NLC) of the Winnipeg Regional Health Authority. The article will contribute to the body of literature about health library services for nurses. Methods: The creation of the service is described. A literature search was undertaken to determine what services have been implemented by librarians for nursing leadership programmes, as well as to review the literature with regard to contributions made by librarians for nursing communities. Results: The literature service, comprised of 19 webliographies based on the NLC's leadership topics, is available on the UMHSL website. A webliography, by definition, is a list of electronic works relating to a particular topic. The NLC created its own website that provides nurses with a means to identify, enhance and evaluate leadership competencies, and which is linked to the UMHSL website. Conclusion: The contributions of the UMHSL librarians to this project support the goals of instilling leadership skills in nurses, encouraging evidence‐based nursing practice, and transforming a practice environment to meet the ultimate goal of effective patient care.  相似文献   
86.
In light of the prevalent use of e-mail between teachers and students, researchers have highlighted the need to assess its uses and effects. Relying on the research and thinking of teacher immediacy and extra-class communication, we developed a scale that measures those e-mail message strategies that influence students' willingness to communicate online with their teachers. Next, we isolated those reasons that students use e-mail to interact with their teachers: (1) to clarify course material and procedures, (2) as a means of efficient communication, and (3) for personal/social reasons. Finally, we examined student characteristics such as gender and ethnicity, and history of e-mail use that may (or may not) influence their attitudes toward e-mail exchanges with teachers.  相似文献   
87.
88.
The sub‐Saharan country of Malawi is steeped in a robust educational reform movement to ensure ‘Education for All’. Based upon country immersion experience and a review of the literature, this report highlights Malawi's nationwide support for its special needs education (SNE) campaign. First discussed is a brief overview of Malawi, its people and its educational philosophy regarding SNE. Comparisons of sub‐Saharan countries’ educational provisions for students with special learning needs follow, as do explanations of the country's classroom practices and its national SNE Policy (revised in 2007). Described along with ‘best practices’ and the country's history of SNE teacher preparation initiatives is the structure of Malawi's SNE implementation, its design in the classroom, teacher preparation particulars and SNE programme milestones. Partners (organisations), integral to the success of Malawi's SNE efforts, are emphasised; and related policies and provisions are presented, along with closing discussion of assessment, diagnosis, programming, and future implications and conclusions.  相似文献   
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