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:      
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   2306篇
  免费   228篇
  国内免费   16篇
耳鼻咽喉   4篇
儿科学   124篇
妇产科学   19篇
基础医学   137篇
口腔科学   13篇
临床医学   284篇
内科学   288篇
皮肤病学   8篇
神经病学   354篇
特种医学   88篇
外科学   45篇
综合类   101篇
一般理论   1篇
预防医学   767篇
眼科学   12篇
药学   267篇
  2篇
中国医学   16篇
肿瘤学   20篇
  2024年   11篇
  2023年   59篇
  2022年   34篇
  2021年   96篇
  2020年   131篇
  2019年   158篇
  2018年   135篇
  2017年   142篇
  2016年   116篇
  2015年   99篇
  2014年   116篇
  2013年   483篇
  2012年   83篇
  2011年   96篇
  2010年   88篇
  2009年   73篇
  2008年   87篇
  2007年   80篇
  2006年   70篇
  2005年   58篇
  2004年   61篇
  2003年   45篇
  2002年   58篇
  2001年   41篇
  2000年   24篇
  1999年   16篇
  1998年   12篇
  1997年   9篇
  1996年   12篇
  1995年   11篇
  1994年   7篇
  1993年   8篇
  1992年   5篇
  1991年   12篇
  1990年   4篇
  1988年   2篇
  1987年   1篇
  1986年   1篇
  1984年   1篇
  1983年   1篇
  1982年   2篇
  1980年   1篇
  1978年   1篇
排序方式: 共有2550条查询结果,搜索用时 281 毫秒
101.
Youth violence has long been regarded as a major social issue. The past decade has, however, seen the scrutiny which encompasses this violence intensify, largely due to a recent media focus on an apparently increasing tendency amongst some young people to engage in acts of ‘appetitive’ or ‘thrill-seeking’ violence. This is reported to be a new form of violence, in which young people act in an excitable state, rather than the more common form of anger-mediated violence. Whilst incidents of appetitive violence are overly represented in the news media and are presented as a major public concern, there is presently no empirical research exploring the validity of this phenomenon and no systematic analysis of the frequency and severity of this form of violent behaviour. Furthermore, the underlying causes of this type of violence are not understood. As such, preventative practices, risk assessment, treatment requirements and targeted management strategies are lacking. The purpose of this review is to examine the current literature on youth violence, particularly youth involvement in ‘thrill-seeking’ acts of violence, as well as describing a range of contemporary factors highlighted as integral to youth violence; specifically, gang involvement, alcohol use and the possession of weapons. This review will also examine an array of international strategies implemented in response to this form of youth violence. Finally, the General Aggression Model (GAM) will be considered to determine whether its framework can assist in advancing our understanding of appetitive violence, by elucidating those characteristics of the individual and their environment that contribute to its expression.  相似文献   
102.
The Risk–Need–Responsivity (RNR) framework is regarded as the forefront of offender rehabilitation in guiding youth offender risk assessment and interventions. This article discusses the juvenile justice system in Singapore and the local research that has been conducted in relation to the RNR framework and the associated Youth Level of Service (YLS) measures. It describes a journey that saw the implementation of the RNR framework across the juvenile justice agencies and highlights the challenges that were faced during the implementation process on the ground. Finally, the article concludes by providing future directions for the implementation of the RNR framework in Singapore.  相似文献   
103.
There has been considerable debate concerning the benefits of children participating in weight training programmes. With the potential benefits of such training in specific rehabilitation regimens, the safety/efficacy of weight training is a topic in need of scientific study. Fifty-two experimental and 39 control subjects participated in this study. A 2 × 2 × 2 (gender by treatment by Tanner stage) ANOVA was used to examine pre- to post-test differences in six strength measures, eight anthropometric measures, five motor performance measures, and one flexibility measure associated with participation in a 12-week progressive resistance programme. In addition, safety of the weight training programme was examined. For strength differences, there were two significant main effects favouring strength gains in males and four favouring the experimental group. For anthropometric changes, 3-way interactions occurred that were not easily explained. However, the predominant main effect was treatment; the experimental group generally experienced gains in body segment girths with decreases in skinfold thickness. For motor performance, the experimental group had greater improvements in three of five parameters. The experimental group also had significantly greater gains in flexibility. The weight training programme was associated with only one injury. These findings support the general observation that physical benefits can be gained safely by children who participate in a weight training programme.  相似文献   
104.
105.
106.

BACKGROUND:

There is limited knowledge concerning chronic bronchitis (CB) in Canadian Aboriginal peoples.

OBJECTIVE:

To determine the prevalence (crude and adjusted) of CB and its associated risk factors in Canadian Aboriginal children and youth six to 14 years of age.

METHODS:

Data from the cross-sectional Aboriginal Peoples Survey were analyzed in the present study. Logistic regression analysis was used to determine risk factors influencing the prevalence of CB among Aboriginal children and youth. The balanced repeated replication method was used to compute standard errors of regression coefficients to account for clustering inherent in the study design. The outcome of interest was based on the question: “Have you been told by a doctor, nurse or other health professional that you have chronic bronchitis?” Demographics, environment and population characteristics (predisposing and enabling resources) were tested for an association with CB.

RESULTS:

The prevalence of CB was 3.1% for boys and 2.8% for girls. Other significant risk factors of CB were age (OR 1.38 [95% CI 1.24 to 1.52] for 12 to 14 year olds versus six to eight year olds), income (OR 2.28 [95% CI 2.02 to 2.59] for income category <$25,000/year versus ≥$85,000/year), allergies (OR 1.96 [95% CI 1.78 to 2.16] for having allergies versus no allergies), asthma (OR 7.61 [ 95% CI 6.91 to 8.37] for having asthma versus no asthma) and location of residence (rural/urban and geographical location). A significant two-way interaction between sex and body mass index indicated that the relationship between the prevalence of CB and body mass index was modified by sex.

DISCUSSION:

The prevalence of CB was related to well-known risk factors among adults, including older age and lower annual income.  相似文献   
107.
Talented athletes use metacognitive skills to improve their performance. Also, it is known that these skills are important for managing one's health. The goal of this study was to identify the relationship between metacognitive skills and overuse injuries in talented tennis players. Metacognitive skills were measured in 73 talented tennis players (45 boys and 28 girls, age 11‐14) at the start of the season, using the Self‐Regulation of Learning Self‐Report Scale. Overuse injuries were monitored for one season using the Oslo Sports Trauma Research Centre Questionnaire on Health Problems. Ordinal regression indicated that moderate or low selfmonitoring skills (compared to high selfmonitoring) (OR 4.555, CI 1.096‐18.927, = 0.037) and exposure time (OR 1.380, CI 1.106‐1.721, P = 0.004) were associated with more time loss overuse injuries. A second analysis showed that this was the case in girls (OR 10.757, CI 1.845‐62.714, P = 0.008), but not in boys. Linear regression revealed that higher reflection scores and exposure time predicted overuse severity (F(5,58) = 2.921, = 0.020, R2 = 0.201). Possibly, selfmonitoring can help players to prevent themselves from time loss overuse injuries. Coaches should be aware that players can differ in selfmonitoring ability and thus in the ability to prevent overuse injuries. The role of reflection needs more research.  相似文献   
108.
The purpose of this study was to examine whether coach‐team perceptual distance regarding the coach‐created motivational climate related to achievement goal orientations and affective responses. To this end, we used polynomial regression analysis with response surface methodology. The sample consisted of 1359 youth soccer players (57.8% male; Mage = 11.81 years, SD = 1.18), belonging to 87 different teams (Msize = 16.47), and 87 coaches (94.6% male, Mage = 42 years, SD = 5.67). Results showed that team perceptions of a coach‐created mastery climate were positively related to team‐rated task goal orientation and enjoyment, whereas team perceptions of a coach‐created performance climate were positively related to team‐rated ego goal orientation and anxiety, and negatively related to team‐rated enjoyment. When the coach and the team were in perceptual agreement, the outcomes increased as both coach and team perceptions of the climate increased. In situations of perceptual disagreement, the most negative effects were seen when the coach held a more favorable perception of the motivational climate compared to the team. The findings highlight the importance of perceptual agreement between the coach and his/her team, contributing to the literature focusing on the effects of the coach‐created motivational climate.  相似文献   
109.
目的探讨青年胰腺肿瘤的临床特点,以提高青年胰腺肿瘤的早期诊断率和治疗效果。方法分析16例青年胰腺肿瘤的临床表现,影像学检查结果,实验室检查结果,临床病理,治疗方法。结果青年胰腺肿瘤首发主要表现为上腹饱胀不适,上腹痛或背部疼;病理类型以腺癌多见;辅助影像学检查中,B超符合率75.0%,CT符合率92.0%,MRI符合率83.0%;根治性手术率为37.5%。患者预后差,5年生存率31.3%。结论青年胰腺肿瘤根治性手术率低,预后差,生存时间较短,应重视青年胰腺肿瘤的临床早期诊断。  相似文献   
110.
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