全文获取类型
收费全文 | 1410501篇 |
免费 | 113517篇 |
国内免费 | 3332篇 |
专业分类
耳鼻咽喉 | 18361篇 |
儿科学 | 46551篇 |
妇产科学 | 41044篇 |
基础医学 | 200726篇 |
口腔科学 | 37694篇 |
临床医学 | 125976篇 |
内科学 | 284311篇 |
皮肤病学 | 33353篇 |
神经病学 | 116867篇 |
特种医学 | 53828篇 |
外国民族医学 | 464篇 |
外科学 | 210477篇 |
综合类 | 32754篇 |
现状与发展 | 3篇 |
一般理论 | 487篇 |
预防医学 | 109994篇 |
眼科学 | 31489篇 |
药学 | 98487篇 |
1篇 | |
中国医学 | 3348篇 |
肿瘤学 | 81135篇 |
出版年
2021年 | 10845篇 |
2019年 | 11663篇 |
2018年 | 16568篇 |
2017年 | 12668篇 |
2016年 | 14261篇 |
2015年 | 16000篇 |
2014年 | 22552篇 |
2013年 | 33381篇 |
2012年 | 45368篇 |
2011年 | 47915篇 |
2010年 | 28149篇 |
2009年 | 27042篇 |
2008年 | 44307篇 |
2007年 | 46810篇 |
2006年 | 47379篇 |
2005年 | 45843篇 |
2004年 | 43733篇 |
2003年 | 41681篇 |
2002年 | 40174篇 |
2001年 | 73000篇 |
2000年 | 74527篇 |
1999年 | 61554篇 |
1998年 | 16987篇 |
1997年 | 15429篇 |
1996年 | 15581篇 |
1995年 | 14788篇 |
1994年 | 13394篇 |
1993年 | 12582篇 |
1992年 | 45835篇 |
1991年 | 43477篇 |
1990年 | 41488篇 |
1989年 | 39549篇 |
1988年 | 36178篇 |
1987年 | 35352篇 |
1986年 | 32859篇 |
1985年 | 31277篇 |
1984年 | 23824篇 |
1983年 | 20023篇 |
1982年 | 12210篇 |
1981年 | 10780篇 |
1979年 | 20701篇 |
1978年 | 14577篇 |
1977年 | 12084篇 |
1976年 | 11364篇 |
1975年 | 11619篇 |
1974年 | 13988篇 |
1973年 | 13533篇 |
1972年 | 12633篇 |
1971年 | 11469篇 |
1970年 | 10910篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Presented in this work is a rare injury of a blunt abdominal trauma in a child. Besides a partial rupture of the kidney and a retro-/intraperitoneal haematoma, a further injury occurred from the accident: an initially clinically indetectable tear of the A. iliaca communis which was found intraoperatively and with systematic CT analysis. Traumatic blood vessel lesions of the abdominal aorta and in particular the iliac blood vessels are very rare in children. By such violent impact injuries, it is therefore vital to perform a clinical examination of the foot pulse, systematic analysis of radiology diagnostics, and intraoperative exploration. The growth phase should be considered for therapy of the blood vessels depending on the child's age group. As the long-term results of graft implants are practically unknown, if possible a primary suture or vein patch should be performed. 相似文献
992.
993.
E Gadelha Figueiredo M Castillo De la Cruz N Theodore P Deshmukh M C Preul 《Minimally invasive neurosurgery》2006,49(1):37-42
We describe a modified keyhole laminoforaminotomy (LF) using anatomic landmarks on the posterior aspect of the cervical vertebral body to decompress the intervertebral foramen with minimal bone removal. Twenty-four procedures were performed at C3-4, C4-5, and C5-6; 12 at C6-7; and 3 at C7-Tl. Facets and laminae structures were identified based on relative surgical perspectives. Bony resection was limited as follows: 1) inferior limit; inferior border of the superior facet; 2) superior limit, superior border of the superior facet; 3) lateral limit, a vertical line linking the junction of the lamina-facet to the lateral end of the superior limit; and 4) lateral aspect of the dural sac. Fluoroscopy was used to confirm that the intervertebral space was reached. The amount of bony removal was quantified for the superior and inferior laminae and facets. The length of the exposed nerve root was measured. The intervertebral foramen was exposed and the intervertebral disc reached in all specimens. Fluoroscopy showed that the center of the exposure remained at the same height with the intervertebral space. The mean length of the nerve root was 4.6 mm; the mean percentage of bony resection was 21.8%, 7.5%, 11.3%, and 11.5% for the superior and inferior laminae and facets, respectively. Opening the intervertebral foramen posteriorly consistently exposed sufficient nerve root length and allowed access to the intervertebral disc. The technique offers the most direct and safest method of decompressing the intervertebral foramen while minimizing bony resection. This simple surgical procedure may help reduce postoperative morbidity. 相似文献
994.
Structure-activity relationship (SAR) between some natural flavonoids and ocular blood flow in the rabbit. 总被引:1,自引:0,他引:1
PURPOSE: Flavonoids with two to five hydroxy groups, with or without sugar, and/or methoxy groups were studied on their effects to affect ocular blood flow. METHODS: Colored microsphere technique was used to determine the ocular blood flow in rabbit eyes. RESULTS: Flavonoids with three free hydroxy (OH) groups seemed to produce the optimal effects in increasing ocular blood flow (naringenin and hesperitin, Pfalts and Bauer, Waterbury, CT). Whether the OH groups are below three (naringenin, hesperitin, Pfalts and Bauer, Waterbury, CT) or above four (Quercetin, Pfalts and Bauer, Waterbury, CT), they produced no effects on the ocular blood flow. When OH groups are four (rutin, Aldrich, Milwaukee, WI), it produced mixed effects on ocular blood flow. The attachment of rutinose and/or methoxy group in the structure did not affect the ocular blood flow one way or the other. CONCLUSION: The ocular blood flow is increased significantly by the number of OH group in the molecule, with three the best to increase the ocular blood flow. 相似文献
995.
996.
997.
998.
Anneloes Dirks Lucianne Groenink Koen G C Westphal Jocelien D A Olivier P Monika Verdouw Jan van der Gugten Mark A Geyer Berend Olivier 《Neuropsychopharmacology》2003,28(10):1790-1798
Chronically elevated levels of corticotropin-releasing factor (CRF) in transgenic mice overexpressing CRF in the brain (CRF-OE) appear to be associated with alterations commonly associated with major depressive disorder, as well as with sensorimotor gating deficits commonly associated with schizophrenia. In the present study, we tested the hypothesis that antipsychotics may be effective in normalizing prepulse inhibition (PPI) of acoustic startle in CRF-OE mice, which display impaired sensorimotor gating compared to wild-type (WT) mice. The typical antipsychotic haloperidol and atypical antipsychotic risperidone improved PPI in the CRF-OE mice, but were ineffective in WT mice. The atypical antipsychotic clozapine did not influence PPI in CRF-OE mice, but reduced gating in WT mice. This effect of clozapine in the CRF-OE mice may thus be regarded as a relative improvement, consistent with the observed effect of haloperidol and risperidone. As expected, the anxiolytic, nonantipsychotic chlordiazepoxide was devoid of any effect. All four compounds dose-dependently reduced the acoustic startle response irrespective of genotype. These results indicate that antipsychotic drugs are effective in improving startle gating deficits in the CRF-OE mice. Hence, the CRF-OE mouse model may represent an animal model for certain aspects of psychotic depression, and could be a valuable tool for research addressing the impact of chronically elevated levels of CRF on information processing. 相似文献
999.
1000.