全文获取类型
收费全文 | 178845篇 |
免费 | 11437篇 |
国内免费 | 707篇 |
专业分类
耳鼻咽喉 | 2503篇 |
儿科学 | 4876篇 |
妇产科学 | 3435篇 |
基础医学 | 23182篇 |
口腔科学 | 3547篇 |
临床医学 | 17506篇 |
内科学 | 38294篇 |
皮肤病学 | 2801篇 |
神经病学 | 17951篇 |
特种医学 | 6213篇 |
外国民族医学 | 13篇 |
外科学 | 26474篇 |
综合类 | 2302篇 |
现状与发展 | 3篇 |
一般理论 | 201篇 |
预防医学 | 13296篇 |
眼科学 | 4790篇 |
药学 | 11515篇 |
中国医学 | 203篇 |
肿瘤学 | 11884篇 |
出版年
2023年 | 697篇 |
2022年 | 1222篇 |
2021年 | 2862篇 |
2020年 | 1762篇 |
2019年 | 2885篇 |
2018年 | 3396篇 |
2017年 | 2454篇 |
2016年 | 2859篇 |
2015年 | 3454篇 |
2014年 | 5106篇 |
2013年 | 7877篇 |
2012年 | 11387篇 |
2011年 | 12247篇 |
2010年 | 6835篇 |
2009年 | 6304篇 |
2008年 | 11530篇 |
2007年 | 12296篇 |
2006年 | 11797篇 |
2005年 | 12159篇 |
2004年 | 11552篇 |
2003年 | 11025篇 |
2002年 | 10635篇 |
2001年 | 1483篇 |
2000年 | 1124篇 |
1999年 | 1590篇 |
1998年 | 2329篇 |
1997年 | 2020篇 |
1996年 | 1702篇 |
1995年 | 1581篇 |
1994年 | 1423篇 |
1993年 | 1352篇 |
1992年 | 1040篇 |
1991年 | 951篇 |
1990年 | 833篇 |
1989年 | 816篇 |
1988年 | 837篇 |
1987年 | 718篇 |
1986年 | 835篇 |
1985年 | 915篇 |
1984年 | 1221篇 |
1983年 | 1173篇 |
1982年 | 1639篇 |
1981年 | 1512篇 |
1980年 | 1416篇 |
1979年 | 785篇 |
1978年 | 907篇 |
1977年 | 802篇 |
1976年 | 709篇 |
1975年 | 567篇 |
1974年 | 597篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
D. Caroline Blanchard Jon K. Shepherd Antonio De Padua Carobrez Robert J. Blanchard 《Neuroscience and biobehavioral reviews》1991,15(4):461-468
Female rats consistently show a pattern of differences in defensive behaviors compared to males which parallel the effects of exposure to a nonpainful threat stimulus (cat or cat odor) in the same tests and measures. These indications of greater defensiveness for females are particularly common in situations involving potential, as opposed to actual and present, threat, a factor which probably also reflects ceiling or floor effects in situations involving very intense defensiveness. In addition, pharmacological studies indicate sex differences in the effects of selective serotonin (5-HT) receptor agonists and antagonists on defensive responding. These findings indicate that sex effects must be considered in studies of the pharmacological control of defensive behaviors, and suggest that responsivity to sex effects may be an additional criterion for the suitability of animal models of anxiety. 相似文献
94.
A primary intrascrotal mass clinically mimicking a testicular tumor was found to be a desmoid tumor originating from the spermatic cord. To our knowledge, this is the first reported case of a paratesticular desmoid tumor. 相似文献
95.
Katherine A Hillman Tanya M Johnson Paul J D Winyard Geoffrey Burnstock Robert J Unwin Adrian S Woolf 《Experimental nephrology》2002,10(1):34-42
BACKGROUND: Purinergic receptors are cell-surface molecules that bind extracellular nucleotides, notably ATP. The P2X family includes seven nonselective ion channels with one member, P2X(7), implicated in cytolytic pore formation and cell death. MATERIALS AND METHODS: We sought P2X(7) expression in mouse nephrogenesis and cpk/cpk renal cyst growth, conditions in which both proliferation and apoptosis are prominent. RESULTS: P2X(7) immunolocalized to condensed metanephric mesenchyme: both proliferation and apoptosis were detected in this compartment, assessed by proliferating cell nuclear antigen expression and propidium iodide-stained pyknotic nuclei respectively. Later in nephrogenesis, P2X(7) was detected in collecting ducts, a pattern persisting to maturity. A mesenchymal to epithelial shift of P2X(7) expression was also documented in ureter development. In cpk/cpk kidneys, P2X(7)-expressing collecting duct cysts dominated histology from two weeks until four weeks after birth, when animals die from uremia. In polycystic kidneys pyknotic nuclei were rarely identified in P2X(7)-expressing epithelia, but were detected between cysts, consistent with a non-apoptotic role for P2X(7) in cyst enlargement. CONCLUSION: P2X(7) is expressed during normal nephrogenesis and in a model of congenital polycystic kidney disease. Further experiments are necessary to define possible functions of P2X(7) in these settings. 相似文献
96.
97.
98.
99.
100.