全文获取类型
收费全文 | 14887篇 |
免费 | 1158篇 |
国内免费 | 28篇 |
专业分类
耳鼻咽喉 | 128篇 |
儿科学 | 489篇 |
妇产科学 | 495篇 |
基础医学 | 1910篇 |
口腔科学 | 340篇 |
临床医学 | 1659篇 |
内科学 | 3420篇 |
皮肤病学 | 358篇 |
神经病学 | 1138篇 |
特种医学 | 431篇 |
外国民族医学 | 3篇 |
外科学 | 2111篇 |
综合类 | 197篇 |
一般理论 | 9篇 |
预防医学 | 1347篇 |
眼科学 | 503篇 |
药学 | 794篇 |
中国医学 | 13篇 |
肿瘤学 | 728篇 |
出版年
2022年 | 116篇 |
2021年 | 274篇 |
2020年 | 168篇 |
2019年 | 272篇 |
2018年 | 318篇 |
2017年 | 252篇 |
2016年 | 225篇 |
2015年 | 265篇 |
2014年 | 391篇 |
2013年 | 548篇 |
2012年 | 765篇 |
2011年 | 778篇 |
2010年 | 448篇 |
2009年 | 373篇 |
2008年 | 621篇 |
2007年 | 609篇 |
2006年 | 623篇 |
2005年 | 617篇 |
2004年 | 569篇 |
2003年 | 526篇 |
2002年 | 530篇 |
2001年 | 473篇 |
2000年 | 442篇 |
1999年 | 352篇 |
1998年 | 130篇 |
1997年 | 115篇 |
1996年 | 106篇 |
1995年 | 103篇 |
1993年 | 105篇 |
1992年 | 368篇 |
1991年 | 333篇 |
1990年 | 294篇 |
1989年 | 313篇 |
1988年 | 285篇 |
1987年 | 293篇 |
1986年 | 251篇 |
1985年 | 239篇 |
1984年 | 180篇 |
1983年 | 169篇 |
1982年 | 104篇 |
1981年 | 109篇 |
1980年 | 104篇 |
1979年 | 185篇 |
1978年 | 140篇 |
1977年 | 123篇 |
1976年 | 100篇 |
1974年 | 127篇 |
1973年 | 122篇 |
1972年 | 100篇 |
1970年 | 100篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Eloise R. Galligan Lindsey Fix Sameera Husain Philip Zachariah Darrell J. Yamashiro Christine T. Lauren 《Journal of cutaneous pathology》2019,46(2):159-161
We report a case of disseminated Trichosporon asahii in a patient on systemic antifungal therapy who presented with multiple cutaneous nodules suggestive of fungal infection. Histologic features resembled neutrophilic eccrine hidradenitis but staining with periodic acid‐Schiff and Gomori methenamine silver confirmed the clinical diagnosis. This case highlights the importance of maintaining suspicion for trichosporonosis and contextualizing histologic findings within the underlying clinical picture. 相似文献
3.
4.
5.
Meir Steiner Richard J. Katz Giulio Baldrighi Bernard J. Carroll 《Psychoneuroendocrinology》1981,6(1):81-90
(1) The estrous cycle in the rat may be used to study recurrent changes in motor behaviors and motivation which are strongly related to cyclic hormonal and CNS changes. (2) The peak in motivated behaviors occurs during a sharply defined period on the night between proestrus and estrus and is evident in facilitated wheel-running, lordosis, and intracranial self-stimulation. (3) Behaviors without a clearly motivated character do not show an estrous cyclicity. (4) The estrous cyclic variation in intracranial self-stimulation was observed at a specific locus — the pars campacta of the substantia nigra. (5) A neurochemical link between sexually motivated behavior, wheel running and intracranial self-stimulation is suggested. This link is in part dopaminergic but is probably also activated by many other systems. 相似文献
6.
R J Katz 《Neuroscience and biobehavioral reviews》1991,15(3):375-381
Intrusive thoughts and images, often of a violent, horrific, or blasphemous nature are the hallmark of Obsessive Compulsive Disorder (OCD). OCD patients frequently also often have reductions in normal serotonergic (5-HT) function. This paper proposes a model of 5-HT function involving the routine filtering and suppression of violent or libidinal impulses. This model accounts for OCD as an instance of failed inhibition. The model also appears to resemble Freud's model of ego-id interactions at least in part, suggesting that it may be possible to psychobiologically substantiate a Freudian metaphor. 相似文献
7.
8.
Local demineralization as a model for bone strength reductions in lytic transcortical metastatic lesions. 总被引:1,自引:0,他引:1
The structural consequences of bone density changes associated with lytic metastatic lesions were investigated using an experimental model of regular, lytic metastatic lesions in bone. Circular holes were drilled in the mid-diaphyseal cortex of paired adult canine femora. The region around the defect was demineralized in one bone of each pair with 0.8 N HCl. Specimens were tested to failure in four-point bending. Defect size was determined from conventional planar radiographs as the maximum apparent defect diameter divided by the periosteal diameter. Demineralization resulted in irregular defect geometries, which increased the maximum defect dimension 33% to 57% with respect to the original drill hole diameter. Demineralization resulted in additional strength reductions beyond those expected from the original drill hole alone. Despite the irregular demineralization patterns observed, strength reductions were in close agreement with those predicted from data for regular, nondemineralized holes (r2 = 0.93). The results demonstrate that irregular diaphyseal defect borders may not require more complex fracture risk predictors than can be determined from analytic and experimental studies of regular defect geometries. Our results also demonstrate that errors of over 100% can occur when measuring diaphyseal defect size from radiographs that are not optimally aligned with respect to the defect. 相似文献
9.
10.
Rebecca P. Ang Robert M. Klassen Wan Har Chong Vivien S. Huan Isabella Y.F. Wong Lay See Yeo Lindsey L. Krawchuk 《Journal of adolescence》2009,32(5):1225-1237
We provide further evidence for the two-factor structure of the 9-item Academic Expectations Stress Inventory (AESI) using confirmatory factor analysis on a sample of 289 Canadian adolescents and 310 Singaporean adolescents. Examination of measurement invariance tests the assumption that the model underlying a set of scores is directly comparable across groups. This study also examined the cross-cultural validity of the AESI using multigroup confirmatory factor analysis across both the Canadian and Singaporean adolescent samples. The results suggested cross-cultural invariance of form, factor loadings, and factor variances and covariances of the AESI across both samples. Evidence of AESI's convergent and discriminant validity was also reported. Findings from t-tests revealed that Singaporean adolescents reported a significantly higher level of academic stress arising from self expectations, other expectations, and overall academic stress, compared to Canadian adolescents. Also, a larger cross-cultural effect was associated with academic stress arising from other expectations compared with academic stress arising from self expectations. 相似文献