全文获取类型
收费全文 | 4501篇 |
免费 | 119篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 89篇 |
妇产科学 | 101篇 |
基础医学 | 270篇 |
口腔科学 | 61篇 |
临床医学 | 357篇 |
内科学 | 637篇 |
皮肤病学 | 42篇 |
神经病学 | 198篇 |
特种医学 | 136篇 |
外科学 | 296篇 |
综合类 | 47篇 |
一般理论 | 4篇 |
预防医学 | 1986篇 |
眼科学 | 20篇 |
药学 | 229篇 |
中国医学 | 14篇 |
肿瘤学 | 131篇 |
出版年
2023年 | 92篇 |
2022年 | 155篇 |
2021年 | 153篇 |
2020年 | 134篇 |
2019年 | 131篇 |
2018年 | 110篇 |
2017年 | 169篇 |
2016年 | 150篇 |
2015年 | 173篇 |
2014年 | 233篇 |
2013年 | 265篇 |
2012年 | 210篇 |
2011年 | 174篇 |
2010年 | 219篇 |
2009年 | 260篇 |
2008年 | 137篇 |
2007年 | 196篇 |
2006年 | 156篇 |
2005年 | 133篇 |
2004年 | 135篇 |
2003年 | 111篇 |
2002年 | 104篇 |
2001年 | 118篇 |
2000年 | 117篇 |
1999年 | 105篇 |
1998年 | 70篇 |
1997年 | 71篇 |
1996年 | 75篇 |
1995年 | 65篇 |
1994年 | 41篇 |
1993年 | 35篇 |
1992年 | 36篇 |
1991年 | 44篇 |
1990年 | 53篇 |
1989年 | 43篇 |
1988年 | 46篇 |
1987年 | 15篇 |
1986年 | 2篇 |
1985年 | 9篇 |
1984年 | 15篇 |
1983年 | 17篇 |
1982年 | 13篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1933年 | 4篇 |
1918年 | 2篇 |
1917年 | 3篇 |
1916年 | 5篇 |
1915年 | 2篇 |
排序方式: 共有4625条查询结果,搜索用时 31 毫秒
31.
32.
33.
34.
35.
Tuberculosis remained a very significant cause of death in Ireland until the mid-20th century and still occupies a prominent position in the folk memory. As I show with reference to recent Irish media coverage, the global resurgence of tuberculosis is therefore viewed with concern in Ireland. Using data collated by the Health Protection Surveillance Centre between 1998 and 2005 however, I show that the recent increase in tuberculosis incidence in Ireland is less than is popularly perceived. This increase is largely associated with economic immigrants attracted to Ireland by the ‘Celtic Tiger’ economic boom, but there is little evidence to suggest that this has had a negative impact on the Irish-born population. Drug resistance is still a small but growing problem. Whilst vigilance is required, it is argued that the recent increase does not at present indicate a likely return to the situation in the mid-20th century. 相似文献
36.
37.
38.
Greater Cape Town has developed a geographical network of perinatal health care services for low-income mothers using community-based clinics with hospital referrals. This study analyzes 25,409 births recorded in 162 different urban residential areas during 1987. The data apply to two populations--black and mixed. Information on the mother, such as height, weight, education, parity, and prenatal visits is indicated by suburb, as well as birth outcomes such as gestational age, birthweight, and method of obstetrical delivery. Comparisons are drawn between black and mixed populations and among suburbs. High utilization rates and successful maternity and infant outcomes suggest that the outreach clinics of Cape Town could provide a model for urban agglomerations in other African countries. 相似文献
39.
Geographic patterns of prostate cancer mortality. Evidence for a protective effect of ultraviolet radiation. 总被引:19,自引:0,他引:19
BACKGROUND. Prostate cancer is the most prevalent nonskin cancer among men in the United States and is the second leading cause of cancer deaths in men. The cause of prostate cancer remains obscure. Recently it was hypothesized that low levels of vitamin D, a hormone with potent antitumor properties, may increase the risk for clinical prostate cancer. METHODS. Because the major source of vitamin D is casual exposure to ultraviolet (UV) radiation, the authors examined the geographic distributions of UV radiation and prostate cancer mortality in 3073 counties of the contiguous United States using linear regression and trend surface analyses. RESULTS. The geographic distributions of UV radiation and prostate cancer mortality are correlated inversely (P < 0.0001). Prostate cancer mortality exhibits a significant north-south trend, with lower rates in the South. These geographic patterns are not readily explicable by other known risk factors for prostate cancer. CONCLUSIONS. These data lend support to the hypothesis that UV radiation may protect against clinical prostate cancer. Viewed in conjunction with other recent data, including those demonstrating a differentiating effect of vitamin D on human prostate cancer cells, these findings suggest that vitamin D may have an important role in the natural history of prostate cancer. 相似文献
40.