全文获取类型
收费全文 | 1181226篇 |
免费 | 74866篇 |
国内免费 | 4232篇 |
专业分类
耳鼻咽喉 | 16501篇 |
儿科学 | 35947篇 |
妇产科学 | 30263篇 |
基础医学 | 177544篇 |
口腔科学 | 34471篇 |
临床医学 | 101199篇 |
内科学 | 226823篇 |
皮肤病学 | 27730篇 |
神经病学 | 86920篇 |
特种医学 | 45320篇 |
外国民族医学 | 181篇 |
外科学 | 180848篇 |
综合类 | 24858篇 |
现状与发展 | 3篇 |
一般理论 | 255篇 |
预防医学 | 73941篇 |
眼科学 | 28802篇 |
药学 | 91279篇 |
4篇 | |
中国医学 | 4666篇 |
肿瘤学 | 72769篇 |
出版年
2021年 | 8792篇 |
2019年 | 8910篇 |
2018年 | 14231篇 |
2017年 | 11049篇 |
2016年 | 12703篇 |
2015年 | 14196篇 |
2014年 | 18499篇 |
2013年 | 26523篇 |
2012年 | 36534篇 |
2011年 | 37246篇 |
2010年 | 22169篇 |
2009年 | 20310篇 |
2008年 | 34942篇 |
2007年 | 38017篇 |
2006年 | 38246篇 |
2005年 | 36483篇 |
2004年 | 35203篇 |
2003年 | 33856篇 |
2002年 | 32992篇 |
2001年 | 64324篇 |
2000年 | 65498篇 |
1999年 | 54239篇 |
1998年 | 13713篇 |
1997年 | 11420篇 |
1996年 | 11020篇 |
1995年 | 10257篇 |
1994年 | 9373篇 |
1993年 | 8638篇 |
1992年 | 38440篇 |
1991年 | 37388篇 |
1990年 | 36212篇 |
1989年 | 35724篇 |
1988年 | 32257篇 |
1987年 | 31281篇 |
1986年 | 29438篇 |
1985年 | 27499篇 |
1984年 | 19765篇 |
1983年 | 16535篇 |
1982年 | 8942篇 |
1979年 | 17591篇 |
1978年 | 12052篇 |
1977年 | 10257篇 |
1976年 | 9269篇 |
1975年 | 10677篇 |
1974年 | 12338篇 |
1973年 | 11726篇 |
1972年 | 11181篇 |
1971年 | 10616篇 |
1970年 | 10064篇 |
1969年 | 9428篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
summary The aetiology of denture stomatitis is not clear from the literature. Some studies show its aetiology as Candida albicans, while other reports point out the significance of microorganisms. In this study the existence of C. albicans and microorganisms was investigated in subjects with and without denture stomatitis. The results showed that a combination of C. albicans and microorganisms is more likely to be responsible for denture stomatitis. 相似文献
92.
In this paper, the authors describe some of the complexities of collecting and presenting data on race and ethnicity based on the experiences of the Bureau of the Census. Different methods of data collection, different content and format of questions, and different definitions make it difficult to collect consistent race and ethnic data across data systems. The Bureau of the Census experiences have shown that changing ethnic self-identity and concepts, intent of the question, consistency of reporting, and the classification of persons of mixed racial parentage affect the quality of the data. These are some of the issues that must be addressed as statistical agencies and researchers seek to provide comparable race and ethnic data. 相似文献
93.
P J Hayden C J Welsh Y Yang W H Schaefer A J Ward J L Stevens 《Chemical research in toxicology》1992,5(2):232-237
Nephrotoxic cysteine conjugates derived from a variety of halogenated alkenes are enzymatically activated via the beta-lyase pathway to yield reactive sulfur-containing metabolites which bind covalently to cellular macromolecules. Mitochondria contain beta-lyase enzymes and are primary targets for binding and toxicity. Previously, mitochondrial protein and/or DNA have been considered as molecular targets for cysteine conjugate metabolite binding. We now report that metabolites of nephrotoxic cysteine conjugates form covalent adducts with rat kidney mitochondrial phospholipids. Rat kidney mitochondria were incubated with the 35S-labeled conjugates S-(1,1,2,2-tetrafluoroethyl)-L-cysteine (TFEC), S-(2-chloro-1,1,2-trifluoroethyl)-L-cysteine (CTFC), S-(1,2-dichlorovinyl)-L-cysteine, and S-(1,2,3,4,4-pentachlorobutadienyl)-L-cysteine. Quantitation of metabolite binding to whole mitochondria and to mitochondrial protein and lipid fractions revealed that as much as 42% of the 35S-label associated with the mitochondria was found in the lipid fraction. Total lipids were also extracted from 35S-treated mitochondria and separated by thin-layer chromatography. 35S-Containing metabolites were found in the lipid fractions from mitochondria treated with each of the conjugates. Lipids from both [35S]CTFC- and [35S]-TFEC-treated mitochondria contained major 35S-labeled lipid adducts which had similar mobility by thin-layer chromatography. Fatty acid analysis, 19F and 31P NMR spectroscopy, and mass spectrometric analyses confirmed that the major TFEC and CTFC adducts are thioamides of phosphatidylethanolamine. 相似文献
94.
95.
Two-color flow cytometry was carried out to determine the correlation between cell-mediated immunity and the levels of proteinuria in 30 patients with membranous nephropathy. Lymphocyte subpopulations were measured by two-color flow cytometry using various monoclonal antibodies of the Leu series. Clinically, the patients were divided into four stages as follows: 1. untreated nephrotic stage, 2. prednisolone (PSL) treated nephrotic stage, 3. persistent proteinuric stage (incomplete remission, ICR) and 4. complete remission (CR). Two-color flow cytometry showed a significant decrease in Leu 2a+15+ (suppressor T) cells and relative increase in Leu 3a+8+ (suppressor inducer T) cells in the untreated nephrotic stage. The mean Leu 3a+8-/Leu 2a+15+ (helper/suppressor) cell ratio was normalized in the persistent proteinuric stage or complete remission after treatment with PSL. Patients with membranous nephropathy showed a significant elevation of Leu 2a+DR+ cells after treatment with PSL. The abnormalities of suppressor T cells and suppressor inducer T cells in the peripheral blood appear to reflect the levels of proteinuria in patients with membranous nephropathy. It was concluded that PSL might stimulate Leu 2a positive cells and then increase the number of Leu 2a+15+ cells in the peripheral blood of patients with membranous nephropathy. 相似文献
96.
97.
98.
Pankaj Hari Anand Srivastava Arun Kumar Gupta Rajendra N. Srivastava 《Pediatric nephrology (Berlin, Germany)》1997,11(4):497-498
Acute renal failure (ARF) developed in a 7-week-old infant due to bilateral candidal bezoars (fungal balls) causing obstruction
at the pelviureteric junction. The baby was born at term with an appropriate birthweight, and had been treated with broad-spectrum
antibiotics for respiratory distress and septicemia during the 1st week of life. Recovery from ARF followed renal decompression
with bilateral nephrostomy tube placement and parenteral administration of amphotericin B and 5-flucytosine.
Received August 21, 1996; received in revised form and accepted January 3, 1997 相似文献
99.
100.