全文获取类型
收费全文 | 439557篇 |
免费 | 37552篇 |
国内免费 | 25465篇 |
专业分类
耳鼻咽喉 | 4034篇 |
儿科学 | 5964篇 |
妇产科学 | 7362篇 |
基础医学 | 54824篇 |
口腔科学 | 8797篇 |
临床医学 | 54134篇 |
内科学 | 66332篇 |
皮肤病学 | 5110篇 |
神经病学 | 24784篇 |
特种医学 | 16100篇 |
外国民族医学 | 216篇 |
外科学 | 48342篇 |
综合类 | 64060篇 |
现状与发展 | 88篇 |
一般理论 | 62篇 |
预防医学 | 30036篇 |
眼科学 | 12171篇 |
药学 | 44647篇 |
363篇 | |
中国医学 | 21395篇 |
肿瘤学 | 33753篇 |
出版年
2024年 | 3882篇 |
2023年 | 5385篇 |
2022年 | 13398篇 |
2021年 | 16997篇 |
2020年 | 13237篇 |
2019年 | 11679篇 |
2018年 | 12486篇 |
2017年 | 11212篇 |
2016年 | 10574篇 |
2015年 | 15747篇 |
2014年 | 19649篇 |
2013年 | 18341篇 |
2012年 | 27011篇 |
2011年 | 30287篇 |
2010年 | 19488篇 |
2009年 | 15836篇 |
2008年 | 20749篇 |
2007年 | 20903篇 |
2006年 | 20840篇 |
2005年 | 20108篇 |
2004年 | 13944篇 |
2003年 | 13477篇 |
2002年 | 11581篇 |
2001年 | 14048篇 |
2000年 | 14315篇 |
1999年 | 13281篇 |
1998年 | 6755篇 |
1997年 | 6401篇 |
1996年 | 4859篇 |
1995年 | 4574篇 |
1994年 | 3877篇 |
1993年 | 2824篇 |
1992年 | 5878篇 |
1991年 | 5582篇 |
1990年 | 5055篇 |
1989年 | 4772篇 |
1988年 | 4428篇 |
1987年 | 4122篇 |
1986年 | 3707篇 |
1985年 | 3464篇 |
1984年 | 2318篇 |
1983年 | 1938篇 |
1979年 | 1970篇 |
1978年 | 1184篇 |
1975年 | 1191篇 |
1974年 | 1358篇 |
1973年 | 1413篇 |
1972年 | 1357篇 |
1971年 | 1247篇 |
1970年 | 1137篇 |
排序方式: 共有10000条查询结果,搜索用时 18 毫秒
71.
Comparative Efficacy and Safety of Phosphate Binders in Hyperphosphatemia Patients With Chronic Kidney Disease 下载免费PDF全文
Xiuqin Yang MD Qingning Bai MD Yanguo Li MD Haijun Liu MD Haiying Guo MD Xiaolei Zhang MD 《JPEN. Journal of parenteral and enteral nutrition》2018,42(4):766-777
Background: In this study, we coordinated a network meta‐analysis to establish the efficacy and safety of different agents used in the treatment of hyperphosphatemia patients with chronic kidney disease. Methods: PubMed, CNKI, and Embase were systematically searched to retrieve relevant studies. Outcomes were presented by mean differences, odds ratios, and corresponding 95% credible intervals for continuous outcomes and binary outcomes, respectively. Each therapy was ranked according to the value of surface under the cumulative ranking curve. Consistencies between direct and indirect comparisons were assessed with a node‐splitting plot. Results: In terms of efficacy end points (including levels of serum phosphate, serum calcium, serum intact parathyroid hormone, and serum calcium × phosphorus product), all 7 kinds of agents outperformed or performed at least equally to placebo, with iron‐based phosphate‐binding agents being potentially the most effective. As for safety end points (including mortality, adverse events, and all‐cause discontinuation), almost all agents were equivalent in term of mortality and all‐cause discontinuation except in the comparison between iron‐based phosphate‐binding agents and placebo. Meanwhile, iron‐based phosphate‐binding agents colestilan and nicotinic acid performed poorly compared with placebo in terms of adverse events. Furthermore, iron‐based phosphate‐binding agents were potentially the safest agents followed sequentially by calcium‐based phosphate‐binding agents and placebo. Conclusion: Iron‐based phosphate‐binding agents were the preferable agents when considering efficacy and safety simultaneously. 相似文献
72.
Comparing the Effectiveness of Dynamic Treatment Strategies Using Electronic Health Records: An Application of the Parametric g‐Formula to Anemia Management Strategies 下载免费PDF全文
73.
Xinxin Liu Jian Yang Shuang Song Hong Song Danni Ai Jianjun Zhu Yurong Jiang Yongtian Wang 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2018,41(2):495-505
74.
75.
Jian Li Yulian Yan Nannan Yue Qiyong Luo Wanjun Li Xiaojun Xie 《Bulletin of environmental contamination and toxicology》2018,100(1):26-31
Poland is one of the countries distinguished by a long and colorful past. Undergoing numerous turbulent socio-economic changes forced by the course of history, Poland is now one of the member states of the European Union. Experiencing low water quantity and high contamination levels in surface waters, Poland is following other EU countries in the effort to reach a “good” water status. Herein are presented impacts of changes in Polish history on water legislation, management, and research, as well as explanations for the perceptible split between engineering and scientific approaches to the aquatic issues. Drawbacks caused by unsatisfactory state research funding for the sciences and division of the water related contemporary scientific interests are also discussed. 相似文献
76.
77.
78.
79.
ABSTRACTDespite significant health benefits of regular physical activity, over 60 percent of college women do not meet recommended physical activity guidelines to promote their health and health-related quality of life (HRQoL), a comprehensive construct including physical and psychosocial health functioning. The major purpose of this study was to examine the influences of individual (e.g., self-efficacy, enjoyment), social (e.g., family and friend support), and physical environmental factors (e.g., crime safety) on college women’s physical activity and HRQoL. Participants were 235 (Mean age = 21.0 years) college women from a public research university located in the southwest region of the United States. They completed validated surveys assessing their perceptions of physical activity, HRQoL, and social ecological factors during the spring semester of 2012. The findings of three multiple linear regressions, entering individual factors first, followed by social and physical environmental factors, revealed that self-efficacy and crime safety were significantly related to physical activity. For HRQoL-physical functioning, significant factors were self-efficacy, enjoyment, and crime safety. Enjoyment was the only factor related to HRQoL-psychosocial functioning. These findings indicated that physical activity professionals need to foster safe environments, enhance self-efficacy, and provide enjoyable activities to promote college women’s physical activity and HRQoL. 相似文献
80.
Kiran Kumar Soni Li Tao Zhang Bo Ram Choi Keshab Kumar Karna Jae Hyung You Yu Seob Shin 《Pharmaceutical biology》2018,56(1):94-103
Context: MOTILIPERM was prepared as a mixture of extracts of three medicinal herbs [roots of Morinda officinalis How (Rubiaceae), outer scales of Allium cepa L. (Liliaceae) and seeds of Cuscuta chinensis Lamark (Convolvulaceae)].Objective: To investigate the role of reactive oxygen species (ROS)-based endoplasmic reticulum (ER) stress in a rat model of varicocele and the therapeutic efficacy of MOTILIPERM in this model.Materials and methods: Sixty male rats were divided into five experimental groups: a normal control group (CTR?+?vehicle), a control group administered MOTILIPERM 200?mg/kg (CTR?+?M 200), a varicocele-induced control group (VC?+?vehicle) and two varicocele-induced groups administered MOTILIPERM 100 (VC?+?M 100) or 200 (VC?+?M 200) mg/kg for 4 weeks. Testis weights were recorded and serums were assayed for hormone concentrations. Tissues were subjected to semen analysis, histopathology, analyses of ER response protein expression levels and oxidative stress were assessed by measuring ROS, reactive nitrogen species (RNS), malondialdehyde (MDA) level and ratios of total glutathione (GSH)/oxidized GSH (GSSG).Results: MOTILIPERM treatment of varicocele-induced groups significantly increased left testis weight, testosterone level, sperm motility, count and spermatogenic cell density. ER-response protein expression levels were dose-dependently decreased in VC?+?M 200 group compared with VC?+?vehicle group. MOTILIPERM treatment also decreased MDA and ROS/RNS level but increased GSH/GSSG ratio.Discussion and conclusions: This study suggests that ROS-related ER stress may play a major role in varicocele-induced infertility and MOTILIPERM, a novel compound targeting ROS-based ER stress, may be therapeutically useful in treatment of varicocele, or as a supplement for the treatment of infertility. 相似文献