全文获取类型
收费全文 | 661篇 |
免费 | 48篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 7篇 |
妇产科学 | 19篇 |
基础医学 | 81篇 |
口腔科学 | 17篇 |
临床医学 | 46篇 |
内科学 | 148篇 |
皮肤病学 | 6篇 |
神经病学 | 182篇 |
特种医学 | 10篇 |
外科学 | 55篇 |
综合类 | 2篇 |
预防医学 | 47篇 |
眼科学 | 31篇 |
药学 | 39篇 |
肿瘤学 | 21篇 |
出版年
2022年 | 5篇 |
2021年 | 8篇 |
2020年 | 10篇 |
2019年 | 13篇 |
2018年 | 7篇 |
2017年 | 17篇 |
2016年 | 23篇 |
2015年 | 25篇 |
2014年 | 25篇 |
2013年 | 40篇 |
2012年 | 38篇 |
2011年 | 41篇 |
2010年 | 31篇 |
2009年 | 23篇 |
2008年 | 37篇 |
2007年 | 33篇 |
2006年 | 39篇 |
2005年 | 34篇 |
2004年 | 26篇 |
2003年 | 36篇 |
2002年 | 13篇 |
2001年 | 11篇 |
2000年 | 13篇 |
1999年 | 9篇 |
1997年 | 3篇 |
1995年 | 3篇 |
1992年 | 7篇 |
1991年 | 4篇 |
1990年 | 7篇 |
1989年 | 4篇 |
1987年 | 7篇 |
1986年 | 4篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1982年 | 3篇 |
1979年 | 7篇 |
1978年 | 3篇 |
1975年 | 5篇 |
1974年 | 9篇 |
1973年 | 6篇 |
1972年 | 11篇 |
1971年 | 6篇 |
1970年 | 4篇 |
1969年 | 3篇 |
1967年 | 4篇 |
1943年 | 3篇 |
1942年 | 3篇 |
1941年 | 5篇 |
1940年 | 3篇 |
1939年 | 3篇 |
排序方式: 共有714条查询结果,搜索用时 15 毫秒
51.
52.
53.
Björn Wettermark Marie E Persson Nils Wilking Mats Kalin Seher Korkmaz Paul Hjemdahl Brian Godman Max Petzold Lars L Gustafsson the Regional Drug Expert Consortium in Stockholm County Council 《BMC health services research》2010,10(1):128
Background
New pharmacological therapies are challenging the healthcare systems, and there is an increasing need to assess their therapeutic value in relation to existing alternatives as well as their potential budget impact. Consequently, new models to introduce drugs in healthcare are urgently needed. In the metropolitan health region of Stockholm, Sweden, a model has been developed including early warning (horizon scanning), forecasting of drug utilization and expenditure, critical drug evaluation as well as structured programs for the introduction and follow-up of new drugs. The aim of this paper is to present the forecasting model and the predicted growth in all therapeutic areas in 2010 and 2011. 相似文献54.
Nattermann J Nischalke HD Hofmeister V Kupfer B Ahlenstiel G Feldmann G Rockstroh J Weiss EH Sauerbruch T Spengler U 《Antiviral therapy》2005,10(1):95-107
HIV has evolved several strategies to evade recognition by the host immune system including down-regulation of major histocompatibility complex (MHC) class I molecules. However, reduced expression of MHC class I molecules may stimulate natural killer (NK) cell lysis in cells of haematopoietic lineage. Here, we describe how HIV counteracts stimulation of NK cells by stabilizing surface expression of the non-classical MHC class I molecule, HLA-E. We demonstrate enhanced expression of HLA-E on lymphocytes from HIV-infected patients and show that in vitro infection of lymphocytes with HIV results in up-regulation of HLA-E expression and reduced susceptibility to NK cell cytotoxicity. Using HLA-E transfected K-562 cells, we identified the well-known HIV T-cell epitope p24 aa14-22a as a ligand for HLA-E that stabilizes surface expression of HLA-E, favouring inhibition of NK cell cytotoxicity. These results propose HIV-mediated up-regulation of HLA-E expression as an additional evasion strategy targeting the antiviral activities of NK cells, which may contribute to the capability of the virus in establishing chronic infection. 相似文献
55.
In vitro activity of micafungin (FK-463) against Candida spp.: microdilution,time-kill,and postantifungal-effect studies
下载免费PDF全文
![点击此处可从《Antimicrobial agents and chemotherapy》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Ernst EJ Roling EE Petzold CR Keele DJ Klepser ME 《Antimicrobial agents and chemotherapy》2002,46(12):3846-3853
We evaluated the in vitro activity of the new echinocandin antifungal micafungin against Candida spp. using microdilution and time-kill methods. Additionally, we examined the postantifungal effect (PAFE) of micafungin. Finally, we evaluated the effect of the addition of serum and plasma on the MIC of micafungin. Four Candida albicans isolates and two isolates of each Candida glabrata, Candida krusei, and Candida tropicalis were selected for testing. The MICs of micafungin were determined in RPMI 1640 medium buffered with morpholinepropanesulfonic acid alone and with the addition of 10, 20, and 50% human serum and plasma. MICs were determined by using two endpoints: a prominent reduction in growth (the MIC at which 80% of isolates are inhibited [MIC(80)]) and complete visual inhibition of growth (MIC(100)). The minimum fungicidal concentration (MFC) of micafungin for each isolate was also determined. Time-kill curves were determined for each isolate in RPMI 1640 medium with micafungin at concentrations ranging from 0.125 to 16 times the MIC(80) to assess the correlation between MIC(80) and fungicidal activity. PAFE studies were conducted with each isolate by using concentrations ranging between 0.25 and 4 times the MIC(80). The MIC(80)s for the test isolates ranged from 0.0039 to 0.25 micro g/ml. Overall, the addition of serum or plasma increased the MIC 6 to 7 doubling dilutions for C. albicans and 3 to 4 doubling dilutions for C. krusei and C. tropicalis. Micafungin time-kill studies demonstrated fungicidal activity at concentrations ranging from 4 to 16 times the MIC(80). Micafungin is very potent agent against a variety of Candida spp., producing fungicidal activity against 7 of 10 isolates tested. A PAFE was observed against all isolates. The PAFE was influenced by the drug concentration, with the highest concentration resulting in the longest observed PAFE in each case. The highest concentration tested, four times the MIC, resulted in a PAFE of more than 9.8 h for 5 of 10 isolates tested (range, 0.9 to > or =20.1 h). 相似文献
56.
Pletz MW Petzold P Allen A Burkhardt O Lode H 《Antimicrobial agents and chemotherapy》2003,47(7):2158-2160
We investigated the effect of calcium carbonate on the oral bioavailability of gemifloxacin. Gemifloxacin was administered alone, 2 h before, simultaneously, or 2 h after calcium carbonate in 16 volunteers. Data for 320 mg of gemifloxacin alone were as follows: maximum concentration of drug in serum (C(max)),13 microg/ml; half-life, 7.33 h; and area under the concentration-time curve from 0 h to infinity (AUC( infinity )), 6.79 microg. h/ml. Only simultaneous coadministration of calcium carbonate reduced C(max) (-17%) and AUC( infinity ) (-21%) significantly. 相似文献
57.
58.
Golo Kronenberg Francesca Regen Isabella Heuser 《Journal of psychiatric research》2009,43(13):1112-1117
Structural neuroimaging studies investigating amygdala volumes in patients suffering from major depression have yielded variable results. Discrepant findings across studies may be attributable in part to heterogeneity with respect to antidepressant medication and to lack of adequate control for the effects of total brain volume and age. Here, 24 unipolar depressed in-patients newly admitted to a psychiatric unit and 14 healthy control participants matched for age, gender, and years of education underwent quantitative magnetic resonance imaging (MRI) toward the end of a one-week washout period. Saliva cortisol was measured at 08.00 and at 16.00 h in patients during washout. Absolute amygdala volumes were significantly reduced in the patient group (by 13% in left amygdala and 12% in right amygdala). The effect of reduced amygdala volumes in patients remained significant after correction for brain volume (BV) and age. Furthermore, amygdala volume measurements in the patient sample showed a significant inverse relationship to the number of preceding depressive episodes. In patients, severity of disease (baseline HAMD scores) and baseline cortisol levels were not related to amygdala volume. This study of a sample of unmedicated depressed in-patients adds to the small, yet growing, body of evidence linking untreated major depression to reduced amygdala volume. 相似文献
59.
60.
Colla M Kronenberg G Deuschle M Meichel K Hagen T Bohrer M Heuser I 《Journal of psychiatric research》2007,41(7):553-560
Structural imaging studies investigating hippocampal volumes in patients suffering from major depression have yielded mixed results. Here, 24 unipolar depressed in-patients and 14 healthy controls carefully matched for age, gender, and years of education underwent quantitative magnetic resonance imaging (MRI). Saliva cortisol was measured at 0800 and 1600 h in patients during a one-week wash-out and the following 4 weeks. Hippocampal volumes were significantly reduced in the patient group even after adjusting for intracranial brain volume (ICV) and age. Across groups, age was significantly negatively correlated with uncorrected hippocampal volumes. In patients, severity of disease (baseline HAMD scores) and baseline cortisol levels were not related to hippocampal volumes. However, there was a negative association between duration of the index episode before hospitalization and hippocampal volumes. Additionally, hippocampal volumes were significantly negatively correlated with duration of illness. Finally, we observed a trend for higher hippocampal volumes in those patients who showed a subsequent decrease in cortisol levels under pharmacotherapy. 相似文献