全文获取类型
收费全文 | 742篇 |
免费 | 45篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 5篇 |
妇产科学 | 25篇 |
基础医学 | 102篇 |
口腔科学 | 14篇 |
临床医学 | 49篇 |
内科学 | 218篇 |
皮肤病学 | 27篇 |
神经病学 | 83篇 |
特种医学 | 26篇 |
外科学 | 66篇 |
综合类 | 3篇 |
一般理论 | 1篇 |
预防医学 | 50篇 |
眼科学 | 16篇 |
药学 | 65篇 |
中国医学 | 1篇 |
肿瘤学 | 33篇 |
出版年
2023年 | 4篇 |
2022年 | 8篇 |
2021年 | 26篇 |
2020年 | 8篇 |
2019年 | 14篇 |
2018年 | 17篇 |
2017年 | 15篇 |
2016年 | 22篇 |
2015年 | 29篇 |
2014年 | 27篇 |
2013年 | 32篇 |
2012年 | 53篇 |
2011年 | 57篇 |
2010年 | 41篇 |
2009年 | 22篇 |
2008年 | 64篇 |
2007年 | 43篇 |
2006年 | 63篇 |
2005年 | 60篇 |
2004年 | 51篇 |
2003年 | 50篇 |
2002年 | 36篇 |
2001年 | 3篇 |
2000年 | 6篇 |
1999年 | 3篇 |
1998年 | 9篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1964年 | 1篇 |
1960年 | 1篇 |
1958年 | 1篇 |
排序方式: 共有789条查询结果,搜索用时 15 毫秒
1.
Photocarcinogenesis and inhibition of intercellular adhesion molecule 1 expression in cells of DNA-repair-defective individuals 下载免费PDF全文
2.
Michael Burwinkel Constanze Riemer Anja Schwarz Julia Schultz Sabine Neidhold Theresa Bamme Michael Baier 《International journal of developmental neuroscience》2004,22(7):497-505
Prion infections of the central nervous system (CNS) are characterised by a reactive gliosis and the subsequent degeneration of neuronal tissue. The activation of glial cells, which precedes neuronal death, is likely to be initially caused by the deposition of misfolded, proteinase K-resistant, isoforms (termed PrP(res)) of the prion protein (PrP) in the brain. Cytokines and chemokines released by PrP(res)-activated glia cells may contribute directly or indirectly to the disease development by enhancement and generalisation of the gliosis and via cytotoxicity for neurons. However, the actual role of prion-induced glia activation and subsequent cytokine/chemokine secretion in disease development is still far from clear. In the present work, we review our present knowledge concerning the functional biology of cytokines and chemokines in prion infections of the CNS. 相似文献
3.
A promising technique for transplantation of bone marrow-derived endothelial progenitor cells into rat heart. 总被引:2,自引:0,他引:2
Cheng Qian René A Tio Anton J M Roks Kristien M Boddeus Martin C Harmsen Wiek H van Gilst Regien G Schoemaker 《Cardiovascular pathology》2007,16(3):127-135
OBJECTIVE: To investigate the feasibility of intracoronary application of endothelial progenitor cells and the subsequent distribution within the heart. METHODS: Endothelial progenitors cells (EPCs) cultured from rat bone marrow were identified by double-positive staining with Dil-Ac-LDL and BS1-lectin. Twenty-four hours before cell transplantation, EPCs were labeled with 5-bromo-2'-deoxyuridine (BrdU). Cells (5 x 10(5) in 250-microl medium) were injected into healthy rats, either as intracoronary application (n=11) or as intramyocardial injection (n = 6). At 15 min or 3 days posttransplantation, hearts as well as other organs (lung, liver, kidney, and spleen) were collected and processed for subsequent BrdU immunohistochemistry. The number of BrdU-positive cells per tissue area was counted. RESULTS: Compared to intramyocardial injection, intracoronary administration resulted in more than twice as much positive cells in the heart (P < .05), with no local differences within the heart. Whereas after 15 min, EPCs were equally distributed in all examined organs (except for the spleen), cells that were still present after 3 days, approximately 10%, were selectively restricted to the heart. CONCLUSIONS: Our data indicate that the intracoronary application provides a promising technique for EPC transplantation in the rat heart. 相似文献
4.
We proposed that double exposure to stressors at work and from family are associated with increased coronary risk in women and that the same exposures are accompanied by depressive feelings. The study group comprised 292 women coronary patients (30-65 years) and 292 age-matched healthy controls. Work-stress, marital-stress, and depressive symptoms were assessed by standardized questionnaires and evaluated in both case-control and 5-year follow-up analyses. We found that double exposure to stress from work and family was accompanied by the highest risk and the worst prognosis in women's coronary disease. In women patients depressive feelings were frequent, and they were more closely related to family than to work stress. In healthy women, both stressors, but in particular their combination, lead to depressive symptoms. 相似文献
5.
Prognostic value of MMP-2, -9 and TIMP-1,-2 immunoreactive protein at the invasive front in advanced head and neck squamous cell carcinomas 总被引:10,自引:0,他引:10
Ondruschka C Buhtz P Motsch C Freigang B Schneider-Stock R Roessner A Boltze C 《Pathology, research and practice》2002,198(8):509-515
In head and neck cancer as well as in other carcinomas, tumor expansion and spread to distant sites require the secretion of destructive enzymes that degrade the extracellular matrix. A variety of proteases contribute to matrix destruction. Characteristics of the invasive tumor front may reflect tumor prognosis better than do other parts of the tumor. Therefore, it was the aim of the present study to (i) compare central and peripheral tumor zones for differences in the expression of matrix-metalloproteinases (MMP) -2 and -9 and their naturally occurring inhibitors (tissue inhibitor of matrix-metalloproteinases (TIMP) -1 and -2), (ii) examine the morphological potential of malignancy, and (iii) correlate these findings with clinicopathological parameters. The study population consisted of 106 surgical specimens of advanced head and neck squamous cell carcinomas. The invasive front was graded for malignancy, and immunohistochemical staining with MMP-2, MMP-9, TIMP-1 and TIMP-2 antibodies was performed. Both MMP-2 and MMP-9 were found to be significantly overexpressed at the tumor front. The MMP-2-positive invasive front exhibited diminished overall survival times. In multivariate analysis, MMP-2 expression retained its correlation with overall survival in addition to nodal status and total malignancy score. Expression of TIMP-2 correlated with local tumor invasion. We conclude that the expression of MMP-2 at the invasive front is a marker of poor survival and appears to be associated with early recurrence in initially lymph node-negative patients. 相似文献
6.
7.
8.
Stehr Paula Weber Winja Rossmann Constanze 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2021,64(1):37-44
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Der Anteil älterer Personen in der Bevölkerung wächst stetig. Gleichzeitig steigen im Alter die Risiken für... 相似文献
9.
10.
Bart Westendorp Regien G Schoemaker Hendrik Buikema Dick de Zeeuw Dirk J van Veldhuisen Wiek H van Gilst 《Journal of the renin-angiotensin-aldosterone system》2004,5(1):27-32
INTRODUCTION: In patients with myocardial infarction (MI)-induced heart failure, angiotensin-converting enzyme (ACE) inhibitors are proven effective therapy in inhibiting the progression towards overt heart failure. However, the prognosis in these patients is still very poor, and optimisation of therapy is warranted. The antihypertensive and renoprotective effects of ACE inhibitors (ACE-Is) can be substantially enhanced by dietary sodium restriction. In line with the latter, the aim of the present study was to explore whether dietary sodium restriction enhances the efficacy of ACE-I after MI. METHODS: Rats with MI-induced left ventricular (LV) dysfunction received ACE-I therapy with zofenopril (5.5 mg/kg/day orally), with or without dietary sodium restriction. ACE activity was measured in non-infarcted LV tissue, kidneys and plasma. Effects on cardiac hypertrophy were examined by means of organ weight/body weight ratios. After blood pressure (BP) measurements, functional consequences of therapy were evaluated as LV pressure development in isolated perfused hearts. RESULTS: Dietary sodium restriction alone had no effect on any of the measured parameters, whereas zofenopril alone significantly reduced plasma and kidney ACE activity, but not LV ACE activity, nor LV weight/body weight ratio. However, only when ACE-I therapy was combined with dietary sodium restriction was LV ACE activity significantly reduced. This effect was paralleled by inhibition of LV hypertrophy. BP was reduced after infarction, and further reduced by zofenopril, but not affected by dietary sodium. Neither treatment was associated with effects on the MI-induced reduction of LV function in vitro. CONCLUSIONS: Effects of ACE inhibition with zofenopril can be potentiated by additional dietary sodium restriction. However, these effects were tissue-specific, since LV, but not kidney or plasma, ACE activity was affected by the additional dietary sodium restriction. Effects on LV ACE activity were paralleled by reduced LV hypertrophy. Since the measured parameters did not indicate any adverse side-effects, dietary sodium restriction may provide a safe strategy to improve ACE-I efficacy in patients with infarction-induced LV dysfunction. 相似文献