全文获取类型
收费全文 | 35593篇 |
免费 | 2690篇 |
国内免费 | 98篇 |
专业分类
耳鼻咽喉 | 344篇 |
儿科学 | 1070篇 |
妇产科学 | 915篇 |
基础医学 | 5389篇 |
口腔科学 | 483篇 |
临床医学 | 5088篇 |
内科学 | 6369篇 |
皮肤病学 | 718篇 |
神经病学 | 3933篇 |
特种医学 | 836篇 |
外科学 | 3290篇 |
综合类 | 277篇 |
现状与发展 | 1篇 |
一般理论 | 33篇 |
预防医学 | 3757篇 |
眼科学 | 618篇 |
药学 | 2301篇 |
中国医学 | 43篇 |
肿瘤学 | 2916篇 |
出版年
2024年 | 32篇 |
2023年 | 280篇 |
2022年 | 434篇 |
2021年 | 906篇 |
2020年 | 605篇 |
2019年 | 934篇 |
2018年 | 1125篇 |
2017年 | 867篇 |
2016年 | 949篇 |
2015年 | 980篇 |
2014年 | 1409篇 |
2013年 | 1802篇 |
2012年 | 2844篇 |
2011年 | 2929篇 |
2010年 | 1577篇 |
2009年 | 1439篇 |
2008年 | 2457篇 |
2007年 | 2524篇 |
2006年 | 2289篇 |
2005年 | 2370篇 |
2004年 | 2123篇 |
2003年 | 1984篇 |
2002年 | 1853篇 |
2001年 | 258篇 |
2000年 | 161篇 |
1999年 | 306篇 |
1998年 | 394篇 |
1997年 | 329篇 |
1996年 | 244篇 |
1995年 | 240篇 |
1994年 | 192篇 |
1993年 | 181篇 |
1992年 | 127篇 |
1991年 | 121篇 |
1990年 | 99篇 |
1989年 | 99篇 |
1988年 | 87篇 |
1987年 | 78篇 |
1986年 | 62篇 |
1985年 | 56篇 |
1984年 | 73篇 |
1983年 | 53篇 |
1982年 | 61篇 |
1981年 | 67篇 |
1980年 | 67篇 |
1979年 | 33篇 |
1978年 | 32篇 |
1977年 | 38篇 |
1976年 | 31篇 |
1974年 | 25篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
33.
Macrophages, dendritic cells or B lymphocytes have been shownto play a major role in the presentation of soluble antigensto CD4+ T cells. In contrast, the capacity of these cells topresent particulate antigens such as bacterial or parasiticantigens to T cells remains controversial. To investigate thisquestion, well defined particulate antigens were prepared bycovalent linkage of proteins or peptides to 1 µm in diametersynthetic microspheres. The T cell immunogenicity of such particulateantigens was analyzed in vitro and in vivo. In vitro, a solubleprotein such as hen egg lysozyme (HEL) coupled to beads stimulateda strong proliferative T cell response of lymph node cells fromHEL-primed mice or of specific T cell hybridomas. HEL coupledto beads was presented to the specific T cell hybridomas bysplenocytes or by peritoneal macrophages, but not by lymphomaB cells. Immunization of mice with several different proteinantigens or with a synthetic peptide covalently linked to beadsinduced strong CD4+ T cell responses in the absence of adjuvant.The strong in vivo immunogenicity of proteins coupled to beadsdid not result from a non-specific adjuvant effect of beadssince covalent linkage of the antigen to beads was strictlyrequired to induce T cell responses in the absence of adjuvant.In vivo treatment by carrageenan showed that macrophages arerequired for the in vivo stimulation of T cell responses bythese particulate antigens. Thus, these results demonstratedthe role of phagocytic cells, especially macrophages, for invivo presentation of particulate antigens. These particulateantigens represent an interesting approach for the developmentof new vaccines, and for the in vivo analysis of the role ofvarious antigen presenting cells in T cell activation and differentiation. 相似文献
34.
35.
Tsutomu Ogata Peter Goodfellow Christine Petit Pierre Maroteaux Nobutake Matsuo 《American journal of medical genetics. Part A》1993,45(1):101-104
This is a follow-up report on a male patient with a 46, Y, r(X) karyotype. Although he had no clinico-radiological features of X-linked recessive chondrodysplasia punctata (CDPX1), molecular studies revealed an Xp terminal deletion involving the putative region for the CDPX1 locus (PABX-DXS31). We suspect that the absence of CDPX1 may be attributable to the nature of the disease and the extreme short stature of the patient (mean – 5.6 S.D.). © 1993 Wiley-Liss, Inc. 相似文献
36.
Christian Prueter Benedikt Habermeyer Christine Norra Christoph M Kosinski 《Movement disorders》2003,18(6):712-713
Due to its low profile for extrapyramidal side-effects, quetiapine has become an alternative to clozapine in the treatment of dopamimetic psychosis in patients with Parkinson's disease (PD). We describe the case of a patient with PD who developed severe akathisia, a common complication with classical antipsychotics, with quetiapine. 相似文献
37.
News for the Practitioner 相似文献
38.
Christine Norra 《Clinical EEG and neuroscience》2007,38(2):66-73
Monoaminergic challenge tests allow investigating central nervous changes in humans under acute depletion of specific neurotransmitters (5-HT, DA, NE). Along with studies using alpha-methyl-para-tyrosine test (AMPT) and phenylalanine/tyrosine depletion test (APTD), the tryptophan depletion test (ATDT) represents the currently most established human challenge tool for the assessment of brain serotonin functioning. Neurophysiological studies in healthy and clinical samples may contribute to the search for a non-invasive and reliable biological marker of monoaminergic vulnerability or dysfunction. In the design of these studies, various biochemical and methodological aspects have to be taken into account. This article focuses on electrophysiological methodology and results of monoamine depletion studies (i.e., electroencephalography, magnetoencephalography, polysomnography, auditory evoked potentials and startle response). 相似文献
39.
Tobias Engelhorn Sophia Goerike Arnd Doerfler Christine Okorn Michael Forsting Gerd Heusch Rainer Schulz 《Journal of cerebral blood flow and metabolism》2004,24(4):467-474
The goal of the present study was to test the impact of administration time of the angiotensin II type 1-receptor blocker candesartan on cerebral blood flow (CBF), infarct size, and neuroscore in transient cerebral ischemia. Therefore, 1-hour middle cerebral artery occlusion (MCAO) was followed by reperfusion. Rats received 0.5-mg/kg candesartan intravenously 2 hours before MCAO (pretreatment), 24 hours after MCAO, every 24 hours after MCAO, or 2 hours before and every 24 hours after MCAO. Infarct size (mm3) and a neuroscore at day 7 were compared with controls. CBF was quantified by radiolabeled microspheres and laser-Doppler flowmetry. Compared with controls (95 +/- 8), infarct size in candesartan-treated groups was smaller (59 +/- 5, 68 +/- 10, 28 +/- 3, and 15 +/- 3, respectively; P<0.05). Although there was no difference in neuroscore between pretreatment and controls (1.55 +/- 0.18, 1.80 +/- 0.13), other treatment regimens resulted in improved neuroscores (1.33 +/- 0.16, 1.11 +/- 0.11, 0.73 +/- 0.15; P<0.05). CBF in pretreated animals at 0.5 hours after MCAO was significantly higher than in controls (0.58 +/- 0.09 mL x g(-1) x min(-1) and 44% +/- 7% of baseline compared with 0.49 +/- 0.06 mL x g(-1) x min(-1) and 37% +/- 6%, microspheres and laser-Doppler flowmetry; P<0.05). Thus, candesartan reduces infarct size even if administered only during reperfusion. Apart from pretreatment, other treatment regimens result in significantly improved neuroscores. In the acute phase of cerebral ischemia, candesartan increases CBF. 相似文献
40.