全文获取类型
收费全文 | 20763篇 |
免费 | 1587篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 188篇 |
儿科学 | 673篇 |
妇产科学 | 538篇 |
基础医学 | 2694篇 |
口腔科学 | 350篇 |
临床医学 | 2376篇 |
内科学 | 4297篇 |
皮肤病学 | 283篇 |
神经病学 | 2246篇 |
特种医学 | 504篇 |
外科学 | 2295篇 |
综合类 | 144篇 |
一般理论 | 18篇 |
预防医学 | 2808篇 |
眼科学 | 254篇 |
药学 | 1187篇 |
中国医学 | 11篇 |
肿瘤学 | 1530篇 |
出版年
2024年 | 42篇 |
2023年 | 349篇 |
2022年 | 587篇 |
2021年 | 1193篇 |
2020年 | 725篇 |
2019年 | 999篇 |
2018年 | 1083篇 |
2017年 | 709篇 |
2016年 | 732篇 |
2015年 | 815篇 |
2014年 | 1024篇 |
2013年 | 1313篇 |
2012年 | 1862篇 |
2011年 | 1816篇 |
2010年 | 869篇 |
2009年 | 719篇 |
2008年 | 1175篇 |
2007年 | 1009篇 |
2006年 | 902篇 |
2005年 | 736篇 |
2004年 | 615篇 |
2003年 | 521篇 |
2002年 | 448篇 |
2001年 | 148篇 |
2000年 | 149篇 |
1999年 | 123篇 |
1998年 | 73篇 |
1997年 | 59篇 |
1995年 | 46篇 |
1994年 | 42篇 |
1992年 | 79篇 |
1991年 | 95篇 |
1990年 | 86篇 |
1989年 | 84篇 |
1988年 | 94篇 |
1987年 | 73篇 |
1986年 | 69篇 |
1985年 | 70篇 |
1984年 | 62篇 |
1981年 | 34篇 |
1980年 | 34篇 |
1979年 | 58篇 |
1978年 | 44篇 |
1977年 | 46篇 |
1976年 | 39篇 |
1975年 | 36篇 |
1974年 | 45篇 |
1973年 | 43篇 |
1972年 | 40篇 |
1970年 | 34篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
Many recent efforts in the field of community psychology have been dedicated to moving from values to action in incorporating diversity into our work. An essential aspect of this goal is designing research that provides opportunities for underrepresented perspectives to be heard. The voices of refugee women, in particular, are not typically incorporated in research, planning for service provision, and policy design. This article explores methodological challenges involved in conducting research with refugee women who are marginalized both within broader U.S. contexts and within their own communities. Six guiding principles are presented: 1) develop strategies for involving marginalized refugee women; 2) consider the advantages and limitations of quantitative and qualitative methodologies and be innovative about combining them; 3) prepare for extensive time and effort for quantitative measure construction; 4) consider gendered decision‐making structures in the lives of refugee women and their potential impact on the research process; 5) plan for refugee women's common triple burden of working outside of the home, managing their households, and adjusting to life in a new country; and 6) attend to refugee women's cultural norms about and unfamiliarity with the interview process. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 721–739, 2004. 相似文献
7.
8.
9.
A K Kant A Schatzkin G Block R G Ziegler M Nestle 《Journal of the American Dietetic Association》1991,91(12):1532-1537
We developed a method for evaluating food group intake patterns using dietary recall data (n = 11,529) from the second National Health and Nutrition Examination Survey. We used this method to examine the relationship of these food group intake patterns to nutrient intake and to selected biochemical indexes of nutritional status. We evaluated each 24-hour dietary intake recall for the presence or omission of five broad food groups--dairy, meat, grain, fruit, and vegetable. The five most prevalent patterns and the proportion of the population reporting them was as follows: all food groups, 33.6%; no fruit, 23.9%; no dairy and fruit, 9.0%; no dairy, 8.0%; and no fruit and vegetable, 5.6%. In the most prevalent pattern, all food groups were consumed; this was the only pattern that provided mean amounts of all of the key vitamins and minerals at levels greater than or equal to the Recommended Dietary Allowances (RDAs). This pattern also was reported by the lowest proportion of individuals consuming less than 100% RDA of the key nutrients. Patterns in which both fruit and vegetables were consumed were associated with highest levels of serum vitamin C. The consistency of these results indicates that screening diets for food group consumption can quickly provide meaningful information about their quality. 相似文献
10.
Further evidence of dopamine transporter dysregulation in ADHD: a controlled PET imaging study using altropane. 总被引:4,自引:0,他引:4
Thomas J Spencer Joseph Biederman Bertha K Madras Darin D Dougherty Ali A Bonab Elijahu Livni Peter C Meltzer Jessica Martin Scott Rauch Alan J Fischman 《Neuropsychopharmacology》2007,62(9):1059-1061
BACKGROUND: The dopamine transporter (DAT) is known to be a key regulator of dopamine, and recent studies of genetics, treatment, and imaging have highlighted the role of DAT in attention-deficit/hyperactivity disorder (ADHD). The findings of in vivo neuroimaging of DAT in ADHD have been somewhat discrepant, however. METHOD: Dopamine transporter binding was measured using a highly selective ligand (C-11 altropane) and positron emission tomography (PET). The sample consisted of 47 well-characterized, treatment-na?ve, nonsmoking, non-comorbid adults with and without ADHD. Additionally, control subjects had few symptoms of ADHD. RESULTS: Results showed significantly increased DAT binding in the right caudate in adults with ADHD compared with matched control subjects without this disorder. CONCLUSIONS: These results confirm abnormal DAT binding in the striatum of adults with ADHD and provide further support that dysregulation of DAT may be an important component of the pathophysiology of ADHD. 相似文献