全文获取类型
收费全文 | 1028篇 |
免费 | 17篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 17篇 |
妇产科学 | 5篇 |
基础医学 | 258篇 |
口腔科学 | 15篇 |
临床医学 | 146篇 |
内科学 | 219篇 |
皮肤病学 | 13篇 |
神经病学 | 28篇 |
特种医学 | 40篇 |
外科学 | 146篇 |
综合类 | 10篇 |
预防医学 | 49篇 |
眼科学 | 15篇 |
药学 | 45篇 |
中国医学 | 1篇 |
肿瘤学 | 37篇 |
出版年
2021年 | 11篇 |
2018年 | 16篇 |
2017年 | 10篇 |
2016年 | 9篇 |
2015年 | 14篇 |
2014年 | 15篇 |
2013年 | 34篇 |
2012年 | 18篇 |
2011年 | 25篇 |
2010年 | 13篇 |
2009年 | 20篇 |
2008年 | 25篇 |
2007年 | 24篇 |
2006年 | 29篇 |
2005年 | 29篇 |
2004年 | 25篇 |
2003年 | 29篇 |
2002年 | 18篇 |
2001年 | 18篇 |
2000年 | 19篇 |
1999年 | 15篇 |
1998年 | 15篇 |
1997年 | 13篇 |
1996年 | 11篇 |
1995年 | 12篇 |
1994年 | 11篇 |
1992年 | 25篇 |
1991年 | 29篇 |
1990年 | 31篇 |
1989年 | 37篇 |
1988年 | 35篇 |
1987年 | 33篇 |
1986年 | 25篇 |
1985年 | 30篇 |
1984年 | 24篇 |
1983年 | 23篇 |
1982年 | 9篇 |
1980年 | 16篇 |
1979年 | 17篇 |
1978年 | 11篇 |
1977年 | 12篇 |
1975年 | 25篇 |
1974年 | 21篇 |
1973年 | 19篇 |
1972年 | 19篇 |
1971年 | 12篇 |
1970年 | 19篇 |
1969年 | 9篇 |
1968年 | 12篇 |
1967年 | 10篇 |
排序方式: 共有1047条查询结果,搜索用时 15 毫秒
1.
2.
Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
3.
4.
5.
Plasmapheresis was used to correct blood lipid composition in patients with angina at rest and angina of effort (functional classes 3-4). In addition to a drop in total cholesterol and triglycerides, cholesterol in low and very-low-density lipoproteins fell abruptly, while high-density-lipoprotein cholesterol, on the contrary, increased considerably. Clinical improvement of the patients was also recorded. 相似文献
6.
N S Potekaev O B Minsker A V Biriukov A Ia Malkina S L Orlov 《Terapevticheski? arkhiv》1988,60(10):78-81
The authors made a short review of literature on phaeohyphomycosis and described the first case of this disease in the USSR. It was diagnosed on the basis of mycological investigation. This type of investigation was recommended for patients at risk of developing opportunistic infections. 相似文献
7.
8.
Anfinogenova YJ Baskakov MB Kovalev IV Kilin AA Dulin NO Orlov SN 《Pflügers Archiv : European journal of physiology》2004,449(1):42-55
This study elucidates the role of cell volume in contractions of endothelium-denuded vascular smooth muscle rings (VSMR) from the rat aorta. We observed that hyposmotic swelling as well as hyper- and isosmotic shrinkage led to VSMR contractions. Swelling-induced contractions were accompanied by activation of Ca2+ influx and were abolished by nifedipine and verapamil. In contrast, contractions of shrunken cells were insensitive to the presence of L-type channel inhibitors and occurred in the absence of Ca2+o. Thirty minutes preincubation with bumetanide, a potent Na+,K+,Cl– cotransport (NKCC) inhibitor, decreased Cl–i content, nifedipine-sensitive 45Ca uptake and contractions triggered by modest depolarization ([K+]o=36 mM). Elevation of [K+]o to 66 mM completely abolished the effect of bumetanide on these parameters. Bumetanide almost completely abrogated phenylephrine-induced contraction, partially suppressed contractions triggered by hyperosmotic shrinkage, but potentiated contractions of isosmotically shrunken VSMR. Our results suggest that bumetanide suppresses contraction of modestly depolarized cells via NKCC inhibition and Cl–i-mediated membrane hyperpolarization, whereas augmented contraction of isosmotically shrunken VSMR by bumetanide is a consequence of suppression of NKCC-mediated regulatory volume increase. The mechanism of bumetanide inhibition of contraction of phenylephrine-treated and hyperosmotically shrunken VSMR should be examined further. 相似文献
9.
10.
Nina L. Golitsina Andrey A. Bobkov Irina V. Dedova Dmitrii A. Pavlov Olga P. Nikolaeva Victor N. Orlov Dmitrii I. Levitsky 《Journal of muscle research and cell motility》1996,17(4):475-485
Summary The effects of various modifications of rabbit skeletal myosin subfragment 1 on thermal denaturation of subfragment 1 in ternary complexes with Mg-ADP and orthovanadate (Vi) or beryllium fluoride (BeFx) have been studied by differential scanning calorimetry. It has been shown that specific modifications of SH1 group of Cys-707 by different sulfhydryl reagents, trinitrophenylation of Lys-83, and reductive methylation of lysine residues promote the decomposition of the S1·ADP·Vi complex and change the character of structural transitions of the subfragment 1 molecule induced by the formation of this complex, but they have much less or no influence on subfragment 1 thermal stability in the S1·ADP·BeFx complex. Thus, the differential scanning calorimetric studies on modified subfragment 1 preparations reveal a significant difference between S1·ADP·Vi and S1·ADP·BeFx complexes. It is suggested that S1·ADP·Vi and S1·ADP·BeFx complexes represent structural analogues of different transition states of the ATPase cycle, namely the intermediate states S1**·ADP·Pi and S1*·ATP, respectively. It is also proposed that during formation of the S1·ADP·Vi complex the region containing both Cys-707 and Lys-83 plays an important role in the spread of conformational changes from the active site of subfragment 1 ATPase throughout the structure of the entire subfragment 1 molecule. In such a case, the effects of reductive methylation of lysine residues on the subfragment 1 structure in the S1·ADP·Vi complex are related to the modification of Lys-83. 相似文献