全文获取类型
收费全文 | 2367305篇 |
免费 | 158326篇 |
国内免费 | 3241篇 |
专业分类
耳鼻咽喉 | 32224篇 |
儿科学 | 75921篇 |
妇产科学 | 62688篇 |
基础医学 | 348458篇 |
口腔科学 | 63707篇 |
临床医学 | 211807篇 |
内科学 | 458332篇 |
皮肤病学 | 51773篇 |
神经病学 | 185854篇 |
特种医学 | 88100篇 |
外国民族医学 | 489篇 |
外科学 | 354138篇 |
综合类 | 47519篇 |
现状与发展 | 12篇 |
一般理论 | 848篇 |
预防医学 | 182952篇 |
眼科学 | 54443篇 |
药学 | 175367篇 |
58篇 | |
中国医学 | 4581篇 |
肿瘤学 | 129601篇 |
出版年
2021年 | 19362篇 |
2019年 | 20276篇 |
2018年 | 27144篇 |
2017年 | 20429篇 |
2016年 | 22826篇 |
2015年 | 25661篇 |
2014年 | 36114篇 |
2013年 | 53959篇 |
2012年 | 74688篇 |
2011年 | 79416篇 |
2010年 | 47058篇 |
2009年 | 44568篇 |
2008年 | 74612篇 |
2007年 | 79480篇 |
2006年 | 80295篇 |
2005年 | 77778篇 |
2004年 | 74366篇 |
2003年 | 71692篇 |
2002年 | 69363篇 |
2001年 | 108738篇 |
2000年 | 111451篇 |
1999年 | 93493篇 |
1998年 | 26992篇 |
1997年 | 23659篇 |
1996年 | 24055篇 |
1995年 | 22715篇 |
1994年 | 20894篇 |
1993年 | 19713篇 |
1992年 | 72002篇 |
1991年 | 70071篇 |
1990年 | 68396篇 |
1989年 | 65663篇 |
1988年 | 60304篇 |
1987年 | 59125篇 |
1986年 | 55221篇 |
1985年 | 53006篇 |
1984年 | 39312篇 |
1983年 | 33400篇 |
1982年 | 19859篇 |
1979年 | 35866篇 |
1978年 | 25651篇 |
1977年 | 21230篇 |
1976年 | 20332篇 |
1975年 | 21817篇 |
1974年 | 26148篇 |
1973年 | 24803篇 |
1972年 | 23200篇 |
1971年 | 22038篇 |
1970年 | 20247篇 |
1969年 | 19315篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
121.
122.
123.
Virginia Signal Stephanie Huang Diana Sarfati James Stanley Katherine A. McGlynn 《Nutrition and cancer》2018,70(5):710-736
Dairy consumption has been studied extensively in terms of its relationship with testicular cancer (TC), yet this relationship remains unclear. In this systematic review, we aimed to answer whether TC development is associated with (a) high amounts of dairy product consumption, (b) the type of dairy product consumed, (c) increasing levels of dairy product consumption, and (d) dairy consumption during certain periods during the lifecourse. Following a systematic review of the literature, eight studies (all case-control studies) were included in our review. The included studies varied in terms of the dairy product(s) investigated (milk, cheese, cream, butter, and yoghurt) as well as the type of exposure to dairy consumption (e.g., high vs. low exposure, dose-response, and timing during lifecourse). We found that there was no strong evidence that high levels of dairy consumption are associated with risk of TC, conflicting evidence of a dose–response relationship, inconsistent evidence on whether certain types of dairy are more strongly associated with TC than others, and conflicting evidence that exposure during certain life-course periods affects TC risk more than other periods. There is no consistent evidence to support the premise that dairy product consumption is associated with the risk of TC development. 相似文献
124.
125.
126.
127.
128.
129.
130.
Jill A. McDonald Katherine Selchau Bridget Acquah-Baidoo 《Journal of community health》2018,43(4):705-716
Maternal Zika virus infection (ZIKV) has serious health consequences for unborn offspring. Knowledge about prevention is critical to reducing risk, yet what women in the high-risk US–Mexico border region know about protecting themselves and their babies from ZIKV is mostly unknown. This study aimed to assess knowledge of ZIKV among pregnant and inter-conception women and to identify sources of information that might address knowledge gaps. Clients in five federally-funded, border region Healthy Start programs (N?=?326) were interviewed in late 2016 about their knowledge of ZIKV prevention methods and whether they believed themselves or their babies to be at risk. Sources of information about ZIKV and demographic characteristics were also measured. Chi square tests identified important associations between variables; adjusted odds ratios (AOR) and 95% confidence intervals for knowledge and beliefs were calculated. Among the 305 women aware of ZIKV, 69.5% could name two ways to prevent infection. Only 16.1% of women named using condoms or abstaining from sex as a prevention method. While 75.3% heard about ZIKV first from TV/radio, just 9.5% found the information helpful. Women who received helpful information from health care providers had greater odds of knowing two prevention methods (AOR?=?2.0; 1.1–3.7), when to test for ZIKV (AOR?=?5.2; 2.1–13.2), and how long to delay pregnancy after infection in a male partner (AOR?=?1.9; 1.1–3.2). Those who said web-based and social media sources were helpful had greater odds of knowing when to test for ZIKV (AOR?=?2.8; 1.3–6.3). Results can inform messaging for safe pregnancy and ZIKV prevention. 相似文献