全文获取类型
收费全文 | 1276篇 |
免费 | 66篇 |
国内免费 | 113篇 |
专业分类
儿科学 | 63篇 |
妇产科学 | 10篇 |
基础医学 | 136篇 |
口腔科学 | 22篇 |
临床医学 | 155篇 |
内科学 | 329篇 |
皮肤病学 | 39篇 |
神经病学 | 54篇 |
特种医学 | 362篇 |
外国民族医学 | 1篇 |
外科学 | 38篇 |
综合类 | 40篇 |
预防医学 | 61篇 |
眼科学 | 12篇 |
药学 | 76篇 |
中国医学 | 1篇 |
肿瘤学 | 56篇 |
出版年
2023年 | 3篇 |
2022年 | 3篇 |
2021年 | 5篇 |
2020年 | 5篇 |
2019年 | 9篇 |
2018年 | 15篇 |
2016年 | 21篇 |
2015年 | 20篇 |
2014年 | 19篇 |
2013年 | 37篇 |
2012年 | 8篇 |
2011年 | 25篇 |
2010年 | 45篇 |
2009年 | 48篇 |
2008年 | 23篇 |
2007年 | 63篇 |
2006年 | 32篇 |
2005年 | 51篇 |
2004年 | 13篇 |
2003年 | 14篇 |
2002年 | 12篇 |
2001年 | 14篇 |
2000年 | 22篇 |
1999年 | 20篇 |
1998年 | 91篇 |
1997年 | 96篇 |
1996年 | 103篇 |
1995年 | 63篇 |
1994年 | 61篇 |
1993年 | 64篇 |
1992年 | 9篇 |
1991年 | 27篇 |
1990年 | 23篇 |
1989年 | 46篇 |
1988年 | 37篇 |
1987年 | 48篇 |
1986年 | 28篇 |
1985年 | 44篇 |
1984年 | 19篇 |
1983年 | 15篇 |
1982年 | 25篇 |
1981年 | 20篇 |
1980年 | 30篇 |
1979年 | 8篇 |
1978年 | 11篇 |
1977年 | 16篇 |
1976年 | 26篇 |
1975年 | 15篇 |
1970年 | 2篇 |
1967年 | 1篇 |
排序方式: 共有1455条查询结果,搜索用时 0 毫秒
81.
Patients with bipolar disorder show cognitive deficits and disorganized behavior, which may reflect a disturbance in neural synchronization. We tested whether EEG measures of auditory neural synchronization were abnormal in bipolar disorder. Nineteen symptomatic patients with bipolar disorder and 32 non-psychiatric control subjects were evaluated. Click trains (500 ms duration) presented at 20, 30, 40 and 50 Hz were used to evoke EEG synchronization. Patients with bipolar disorder showed reduced power across the frequencies of stimulation. Phase-locking across trials was also disturbed in bipolar disorder, consistent with poor phase synchronization between the stimulus and EEG. Abnormal high frequency neural synchronization may contribute to cognitive deficits in bipolar disorder. 相似文献
82.
Reliable and comparable analysis of risks to health is key for preventing disease and injury. Causal attribution of morbidity and mortality to risk factors has traditionally been conducted in the context of methodological traditions of individual risk factors, often in a limited number of settings, restricting comparability. 相似文献
83.
Valid, reliable and comparable measures of the health states of individuals and of the health status of populations are critical components of the evidence base for health policy. We need to develop population health measurement strategies that coherently address the relationships between epidemiological measures (such as risk exposures, incidence, and mortality rates) and multi-domain measures of population health status, while ensuring validity and cross-population comparability. 相似文献
84.
During 1998, the Department of Health proposed to use survival rates of cervical and breast cancer in the 1989/90 incidence cohort as indicators of care. Valid interpretation was of concern within Trent and the Trent Cancer Registry responded by performing additional analyses. Trent Cancer Registry registrations for 1989/90 were re-analysed and the stability of districts' ranks for that cohort was investigated using random simulation techniques. Stability of ranks across more recent cohorts was investigated and attempts made to use all available information.The Department of Health's analyses were confirmed by our re-analysis of the 1989/90 cohort: Rotherham residents appeared to have the "worst" survival for cervical cancer, and Sheffield residents for breast cancer, although not statistically significantly so. Random simulations indicated that ranks based on a single cohort are not stable: for example Sheffield (ranked tenth for 1-y breast cancer survival) was ranked third or better in 6% of randomisations. Ranks were also unstable across cohorts: for example Rotherham 1-y cervical cancer survival was ranked tenth for 1989/90, fifth for 1991/92 and tenth for 1993/94. Analysis of 3-y running averages provided better information than the league table approach. Most districts improved over time, to different degrees, and similar sized gaps remained between the "best" and the "worst" districts. This analysis illustrates the need to be circumspect when interpreting "league tables" based on a single year or cohort analysis. League tables are based on ranks: clearly a large difference in rank may reflect only trivial (ie medically unimportant) differences in actual outcome. Lack of a statistically significant difference in survival between two districts does not mean their survival is equivalent. Even for a common cancer, like breast cancer, rankings were unstable from cohort to cohort. At the Registry we propose to perform these trend analyses routinely in future, adjusting, when possible, for the effects of deprivation and stage at diagnosis. 相似文献
85.
86.
Lipohemarthrosis of the knee: a review of recent experiences 总被引:4,自引:0,他引:4
The radiographs of 268 patients with knee trauma were retrospectively reviewed. In 15 patients with intraarticular fracture, the images demonstrated fat-fluid levels. In 28 other patients with intraarticular fracture, only joint effusion without a fat-fluid level was depicted. The presence of a fat-fluid level in the knee indicated fracture in all patients in whom it was seen. The absence of such a level, however, did not exclude intraarticular fracture. 相似文献
87.
88.
89.
90.