全文获取类型
收费全文 | 1917篇 |
免费 | 91篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 56篇 |
妇产科学 | 51篇 |
基础医学 | 170篇 |
口腔科学 | 58篇 |
临床医学 | 141篇 |
内科学 | 345篇 |
皮肤病学 | 27篇 |
神经病学 | 206篇 |
特种医学 | 49篇 |
外科学 | 307篇 |
综合类 | 36篇 |
一般理论 | 3篇 |
预防医学 | 162篇 |
眼科学 | 28篇 |
药学 | 176篇 |
中国医学 | 3篇 |
肿瘤学 | 177篇 |
出版年
2023年 | 7篇 |
2022年 | 12篇 |
2021年 | 34篇 |
2020年 | 12篇 |
2019年 | 34篇 |
2018年 | 34篇 |
2017年 | 21篇 |
2016年 | 28篇 |
2015年 | 44篇 |
2014年 | 53篇 |
2013年 | 71篇 |
2012年 | 151篇 |
2011年 | 153篇 |
2010年 | 98篇 |
2009年 | 62篇 |
2008年 | 139篇 |
2007年 | 134篇 |
2006年 | 131篇 |
2005年 | 130篇 |
2004年 | 123篇 |
2003年 | 114篇 |
2002年 | 109篇 |
2001年 | 30篇 |
2000年 | 23篇 |
1999年 | 19篇 |
1998年 | 25篇 |
1997年 | 22篇 |
1996年 | 22篇 |
1995年 | 13篇 |
1994年 | 14篇 |
1993年 | 5篇 |
1992年 | 9篇 |
1991年 | 17篇 |
1990年 | 7篇 |
1989年 | 6篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 8篇 |
1985年 | 4篇 |
1984年 | 9篇 |
1983年 | 4篇 |
1982年 | 6篇 |
1981年 | 6篇 |
1980年 | 9篇 |
1979年 | 7篇 |
1977年 | 5篇 |
1975年 | 4篇 |
1974年 | 4篇 |
1973年 | 4篇 |
1968年 | 3篇 |
排序方式: 共有2010条查询结果,搜索用时 515 毫秒
31.
Stan Fisher 《The Physician and sportsmedicine》2013,41(6):104-106
As ‘pumping iron’ becomes increasingly popular for children and teenagers, physicians may be called on to advise patients and parents about what's safe—and what's not. Many young people can benefit from strength training and improve their performance in other sports. 相似文献
32.
33.
Steven Novick Yan Shen Harry Yang John Peterson Dave LeBlond Stan Altan 《Journal of biopharmaceutical statistics》2015,25(2):351-371
Dissolution (or in vitro release) studies constitute an important aspect of pharmaceutical drug development. One important use of such studies is for justifying a biowaiver for post-approval changes which requires establishing equivalence between the new and old product. We propose a statistically rigorous modeling approach for this purpose based on the estimation of what we refer to as the F2 parameter, an extension of the commonly used f2 statistic. A Bayesian test procedure is proposed in relation to a set of composite hypotheses that capture the similarity requirement on the absolute mean differences between test and reference dissolution profiles. Several examples are provided to illustrate the application. Results of our simulation study comparing the performance of f2 and the proposed method show that our Bayesian approach is comparable to or in many cases superior to the f2 statistic as a decision rule. Further useful extensions of the method, such as the use of continuous-time dissolution modeling, are considered. 相似文献
34.
Meagan L. Auger Stan B. Floresco 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(2)
Background:
Dysfunction in prefrontal cortex (PFC) GABA transmission has been proposed to contribute to cognitive dysfunction in schizophrenia, yet how this system regulates different cognitive and mnemonic functions remains unclear.Methods:
We assessed the effects of pharmacological reduction of GABAA signaling in the medial PFC of rats on spatial reference/working memory using different versions of the radial-arm maze task. We used a massed-trials procedure to probe how PFC GABA regulates susceptibility to proactive interference. Male rats were well-trained to retrieve food from the same 4 arms of an 8-arm maze, receiving 5 trials/day (1–2min intervals).Results:
Infusions of the GABAA receptor antagonist bicuculline (12.5–50ng) markedly increased working and reference memory errors and response latencies. Similar treatments also impaired short-term memory on an 8-baited arm task. These effects did not appear to be due to increased susceptibility to proactive interference. In contrast, PFC inactivation via infusion of GABA agonists baclofen/muscimol did not affect reference/working memory. In comparison to the pronounced effects on the 8-arm maze tasks, PFC GABAA antagonism only causes a slight and transient decrease in accuracy on a 2-arm spatial discrimination.Conclusions:
These findings demonstrate that prefrontal GABA hypofunction severely disrupts spatial reference and short-term memory and that disinhibition of the PFC can, in some instances, perturb memory processes not normally dependent on the frontal lobes. Moreover, these impairments closely resemble those observed in schizophrenic patients, suggesting that perturbation in PFC GABA signaling may contribute to these types of cognitive deficits associated with the disorder. 相似文献35.
Heath P. Melugin Nels D. Leafblad Christopher L. Camp Stan Conte 《Current reviews in musculoskeletal medicine》2018,11(1):26-34
Purpose of Review
This review examines recent literature on injury epidemiology and prevention in the sport of baseball from youth to professional levels.Recent Findings
Overuse is the predominant mechanism of injury in youth baseball players. Newer stretching and exercise protocols may help prevent these injuries. At the professional level, however, overuse has not been proven to correlate with increased injury incidence, but pitch counts are still monitored. There continues to be a rise in operations performed for baseball-related injuries, including ulnar collateral ligament (UCL) reconstruction, particularly in younger athletes. As the level of play increases, there is significant loss of participation due to injuries, such as the UCL in the upper extremity and the hamstrings in the lower extremity.Summary
Baseball is a widely popular sport, which has led to a focus on injury epidemiology and prevention. While the majority of research regarding baseball injuries focuses on pitchers, fielders and catchers are also at risk. In an attempt to decrease non-contact injuries in the upper and lower extremities, stretching and strengthening exercises are vitally important. Because injury profiles demonstrate significant variability from youth to professional baseball, unique prevention strategies are likely necessary at each level. More research is needed to develop and validate appropriately targeted injury prevention programs.36.
37.
38.
39.