全文获取类型
收费全文 | 3208篇 |
免费 | 208篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 34篇 |
儿科学 | 65篇 |
妇产科学 | 70篇 |
基础医学 | 798篇 |
口腔科学 | 39篇 |
临床医学 | 261篇 |
内科学 | 786篇 |
皮肤病学 | 77篇 |
神经病学 | 271篇 |
特种医学 | 109篇 |
外科学 | 299篇 |
综合类 | 36篇 |
一般理论 | 2篇 |
预防医学 | 206篇 |
眼科学 | 60篇 |
药学 | 215篇 |
中国医学 | 2篇 |
肿瘤学 | 97篇 |
出版年
2023年 | 25篇 |
2022年 | 33篇 |
2021年 | 80篇 |
2020年 | 28篇 |
2019年 | 59篇 |
2018年 | 66篇 |
2017年 | 55篇 |
2016年 | 36篇 |
2015年 | 57篇 |
2014年 | 67篇 |
2013年 | 104篇 |
2012年 | 136篇 |
2011年 | 135篇 |
2010年 | 88篇 |
2009年 | 64篇 |
2008年 | 115篇 |
2007年 | 138篇 |
2006年 | 137篇 |
2005年 | 111篇 |
2004年 | 107篇 |
2003年 | 110篇 |
2002年 | 97篇 |
2001年 | 25篇 |
2000年 | 39篇 |
1999年 | 31篇 |
1998年 | 28篇 |
1997年 | 21篇 |
1992年 | 21篇 |
1989年 | 21篇 |
1987年 | 22篇 |
1984年 | 26篇 |
1982年 | 28篇 |
1978年 | 23篇 |
1975年 | 18篇 |
1974年 | 22篇 |
1973年 | 19篇 |
1972年 | 20篇 |
1937年 | 16篇 |
1934年 | 35篇 |
1933年 | 40篇 |
1932年 | 23篇 |
1931年 | 44篇 |
1930年 | 29篇 |
1929年 | 19篇 |
1928年 | 40篇 |
1926年 | 22篇 |
1925年 | 16篇 |
1924年 | 20篇 |
1923年 | 26篇 |
1922年 | 21篇 |
排序方式: 共有3427条查询结果,搜索用时 31 毫秒
991.
Julius Fridriksson Caroline Nettles Mary Davis Leigh Morrow Allen Montgomery 《Clinical linguistics & phonetics》2013,27(6):401-410
The purpose of this exploratory study was to investigate the relationship between functional communication and executive function ability in aphasia. Twenty‐five participants with aphasia underwent examination with an extensive test battery including measures of functional communication, executive function ability, and language impairment. Compared to published norms, most participants did not perform within normal limits on the executive function tests. As expected, the correlation between severity of language impairment and functional communication ratings exceeded that among the executive functioning and functional communication measures. Eight of ten correlation coefficients for the relationship between executive functioning and functional communication reached statistical significance suggesting a clear relationship between scores on the executive functioning measures and functional communication ability. Based on these results, it appears that decreased executive functioning ability may coincide with decreased functional communication ability in persons with aphasia. 相似文献
992.
Lauren Julius Harris Rodrigo Andrés Cárdenas Michael P. Spradlin Jr Jason B. Almerigi 《Laterality》2013,18(5):548-571
Most adults, especially women, hold infants and objects representing infants, such as dolls, preferentially on the left side. The attention hypothesis credits the effect to left-directed attention for perception of emotionally salient targets, faces being prime examples. Support comes from studies showing stronger left visual hemispace (LVH) biases in left-holders than right-holders on the Chimeric Faces Test (CFT), but control tests with non-social/emotional objects are needed. We therefore observed young women holding a doll, a book, and a bag, and compared their scores with their performance on the CFT. We also assessed their handedness to check on its possible role. Overall, only the doll elicited a significant side bias, with 57% of all holds on the left, 2% in the middle, and 41% on the right. On the CFT, only left-holders had an LVH bias, whereas right-holders had no bias in either direction. Only the doll-hold scores were consistently related to CFT scores, and for none of the objects was handedness related to side-of-hold. 相似文献
993.
Photographic and direct-observation studies show that most adults hold infants on the left side. This basic directional effect is well established, but other details are still uncorroborated, uncertain, or inconsistent across studies. These include the overall strength of the bias, the role of the sex, parental status, and experience of the holder, and the sex and age of the infant. Given their importance for understanding the bias, we sought further information from a large sample of photographs of mothers and fathers, some of them first-time parents, others not, holding their infants in the first minutes, hours, or days after birth. The results confirmed the basic directional effect and provided information on the other variables. They also raise questions for further research, especially as it pertains to the use of photographs vs direct observation. 相似文献
994.
Chae-Seok Lim Elizabeth T. Hoang Kenneth E. Viar Ruth L. Stornetta Michael M. Scott J. Julius Zhu 《Genes & development》2014,28(3):273-289
Fragile X syndrome, caused by the loss of Fmr1 gene function, is the most common form of inherited mental retardation, with no effective treatment. Using a tractable animal model, we investigated mechanisms of action of a few FDA-approved psychoactive drugs that modestly benefit the cognitive performance in fragile X patients. Here we report that compounds activating serotonin (5HT) subtype 2B receptors (5HT2B-Rs) or dopamine (DA) subtype 1-like receptors (D1-Rs) and/or those inhibiting 5HT2A-Rs or D2-Rs moderately enhance Ras–PI3K/PKB signaling input, GluA1-dependent synaptic plasticity, and learning in Fmr1 knockout mice. Unexpectedly, combinations of these 5HT and DA compounds at low doses synergistically stimulate Ras–PI3K/PKB signal transduction and GluA1-dependent synaptic plasticity and remarkably restore normal learning in Fmr1 knockout mice without causing anxiety-related side effects. These findings suggest that properly dosed and combined FDA-approved psychoactive drugs may effectively treat the cognitive impairment associated with fragile X syndrome. 相似文献
995.
996.
997.
998.
Nielsen N Wetterslev J al-Subaie N Andersson B Bro-Jeppesen J Bishop G Brunetti I Cranshaw J Cronberg T Edqvist K Erlinge D Gasche Y Glover G Hassager C Horn J Hovdenes J Johnsson J Kjaergaard J Kuiper M Langørgen J Macken L Martinell L Martner P Pellis T Pelosi P Petersen P Persson S Rundgren M Saxena M Svensson R Stammet P Thorén A Undén J Walden A Wallskog J Wanscher M Wise MP Wyon N Aneman A Friberg H 《American heart journal》2012,163(4):541-548
999.
The reduction of coronary mortality is not as large as one would expect from the observed blood pressure lowering in trials of antihypertensive medications. This is not surprising; hypertension is a complex disease where the high blood pressure is only one of numerous coronary risk factors. Sympathetic overactivity in hypertension, independent of the blood pressure, may be conducive to premature atherosclerosis by inducing insulin resistance and dyslipidemia. Through its trophic effect on blood vessels, sympathetic overactivity potentiates vasoconstriction. This, in turn, accelerates hypertension and the metabolic syndrome. The hypertrophy of small coronary arterioles decreases the coronary reserve and enhances coronary spasms. Tachycardia, which is due to increased sympathetic tone and a decreased parasympathetic tone, favors arrhythmias and sudden death in congestive heart failure and hypertension. Increased hematocrit is frequently found in male patients with hypertension, and high hematocrit is a predictor of coronary heart disease/thrombosis. The increase of hematocrit is in part due to an alpha adrenergic postcapillary venoconstriction. Enhanced sympathetic drive, insulin resistance and dyslipidemia have been demonstrated also in congestive heart failure, but the clinical importance of these findings is not fully understood. 相似文献
1000.