全文获取类型
收费全文 | 6095篇 |
免费 | 300篇 |
国内免费 | 25篇 |
专业分类
耳鼻咽喉 | 68篇 |
儿科学 | 169篇 |
妇产科学 | 110篇 |
基础医学 | 914篇 |
口腔科学 | 501篇 |
临床医学 | 536篇 |
内科学 | 1247篇 |
皮肤病学 | 138篇 |
神经病学 | 485篇 |
特种医学 | 97篇 |
外科学 | 649篇 |
综合类 | 27篇 |
一般理论 | 1篇 |
预防医学 | 610篇 |
眼科学 | 40篇 |
药学 | 399篇 |
中国医学 | 26篇 |
肿瘤学 | 403篇 |
出版年
2023年 | 52篇 |
2022年 | 77篇 |
2021年 | 155篇 |
2020年 | 105篇 |
2019年 | 142篇 |
2018年 | 183篇 |
2017年 | 108篇 |
2016年 | 137篇 |
2015年 | 155篇 |
2014年 | 223篇 |
2013年 | 250篇 |
2012年 | 460篇 |
2011年 | 551篇 |
2010年 | 287篇 |
2009年 | 231篇 |
2008年 | 397篇 |
2007年 | 410篇 |
2006年 | 382篇 |
2005年 | 364篇 |
2004年 | 325篇 |
2003年 | 282篇 |
2002年 | 250篇 |
2001年 | 65篇 |
2000年 | 78篇 |
1999年 | 83篇 |
1998年 | 60篇 |
1997年 | 43篇 |
1996年 | 41篇 |
1995年 | 39篇 |
1994年 | 40篇 |
1993年 | 34篇 |
1992年 | 34篇 |
1991年 | 33篇 |
1990年 | 30篇 |
1989年 | 30篇 |
1988年 | 16篇 |
1987年 | 26篇 |
1986年 | 26篇 |
1985年 | 21篇 |
1984年 | 19篇 |
1983年 | 22篇 |
1982年 | 16篇 |
1981年 | 15篇 |
1979年 | 9篇 |
1977年 | 9篇 |
1976年 | 8篇 |
1974年 | 11篇 |
1973年 | 8篇 |
1972年 | 16篇 |
1967年 | 8篇 |
排序方式: 共有6420条查询结果,搜索用时 109 毫秒
1.
2.
Dalton Luiz Schiessel Ricardo K. Yamazaki Marcelo Kryczyk Isabela Coelho de Castro Adriana A. Yamaguchi Danielle C. T. Pequito 《Nutrition and cancer》2016,68(8):1369-1380
Objective: Polyunsaturated fatty acids n-3 (PUFA n-3) have shown effects in reducing tumor growth, in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) abundantly present in fish oil (FO). When these fatty acids are provided in the diet, they alter the functions of the cells, particularly in tumor and immune cells. However, the effects of α-linolenic fatty acid (ALA), which is the precursor of EPA and DHA, are controversial. Thus, our objective was to test the effect of this parental fatty acid. Methods: Non-tumor-bearing and tumor-bearing Wistar rats (70 days) were supplemented with 1 g/kg body weight of FO or Oro Inca® (OI) oil (rich in ALA). Immune cells function, proliferation, cytokine production, and subpopulation profile were evaluated. Results: We have shown that innate immune cells enhanced phagocytosis capacity, and increased processing and elimination of antigens. Moreover, there was a decrease in production of pro-inflammatory cytokines (tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6)) by macrophages. Lymphocytes showed decreased proliferation capacity, increased cluster of differentiation 8 (CD8+) subpopulation, and increased TNF-α production. Conclusions: Oil rich in ALA caused similar immune modulation in cancer when compared with FO. 相似文献
3.
4.
Anne-Marie Selzler Veronica Moore Razanne Habash Lauren Ellerton Erica Lenton Roger Goldstein 《COPD》2020,17(4):452-461
Abstract The purpose of this study was to investigate the strength of the relationships between self-efficacy and (i) functional exercise capacity and (ii) physical activity in chronic obstructive pulmonary disease (COPD), and whether self-efficacy assessment type (i.e., COPD symptoms, exercise-task, exercise-barrier, general, falls) and physical activity assessment type (i.e., self-report vs. objective) are moderators. A systematic search of COPD and self-efficacy concepts was conducted using eight databases from inception to 23 January 2019. Studies were included if they provided correlation coefficients of the relationship between self-efficacy and functional exercise capacity or physical activity, were conducted in adults diagnosed with COPD, and were published in English-language journals. A total of 14 correlation coefficients were included in the self-efficacy and functional exercise capacity meta-analysis, and 16 in the self-efficacy and physical activity meta-analysis. Data were screened, reviewed, and extracted independently by two reviewers, with discrepancies resolved by a third reviewer. Stronger self-efficacy was associated with better functional exercise capacity (weighted r?=?0.38, 95%CI [0.25, 0.50]), and greater physical activity (weighted r?=?0.25, 95%CI [0.17, 0.34]). Exercise-task self-efficacy had the strongest relationship to functional exercise capacity (weighted r?=?0.64, 95% CI [0.51, 0.73]). For physical activity, the type of self-efficacy most strongly related was inconclusive. In COPD, self-efficacy has a relationship to functional exercise capacity and physical activity, the strength of which is influenced by the choice of self-efficacy measure. An understanding of these relationships will assist clinicians in selecting the self-efficacy measure most closely related to the outcome of interest. 相似文献
5.
Is it possible to modify intake behaviors for body weight control purposes? Over the last 40 years, dozens of international, peer-reviewed articles have described behavior modification approaches aiming at body weight reduction. The present article first presents a historical account of behavioral methods and their results. From the early therapies exclusively addressing behaviors (excluding restrictive diets) until the recent cognitive-behavioral treatments, published studies have reported modest weight losses associated with numerous metabolic, nutritional and psychological benefits whose maintenance, beyond the treatment duration, appear reasonably good. Recent studies specifically address the conditions of long-term maintenance. The main elements of behavioral-cognitive treatments are described briefly. Finally, the particular problems associated with these approaches in the French context are underlined. 相似文献
6.
7.
8.
9.