全文获取类型
收费全文 | 1346篇 |
免费 | 72篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 52篇 |
妇产科学 | 12篇 |
基础医学 | 122篇 |
口腔科学 | 11篇 |
临床医学 | 142篇 |
内科学 | 332篇 |
皮肤病学 | 33篇 |
神经病学 | 65篇 |
特种医学 | 55篇 |
外国民族医学 | 10篇 |
外科学 | 211篇 |
综合类 | 18篇 |
预防医学 | 170篇 |
眼科学 | 57篇 |
药学 | 53篇 |
中国医学 | 1篇 |
肿瘤学 | 67篇 |
出版年
2023年 | 11篇 |
2022年 | 17篇 |
2021年 | 37篇 |
2020年 | 17篇 |
2019年 | 41篇 |
2018年 | 54篇 |
2017年 | 26篇 |
2016年 | 39篇 |
2015年 | 25篇 |
2014年 | 42篇 |
2013年 | 78篇 |
2012年 | 91篇 |
2011年 | 116篇 |
2010年 | 51篇 |
2009年 | 50篇 |
2008年 | 89篇 |
2007年 | 95篇 |
2006年 | 88篇 |
2005年 | 71篇 |
2004年 | 62篇 |
2003年 | 65篇 |
2002年 | 70篇 |
2001年 | 25篇 |
2000年 | 14篇 |
1999年 | 19篇 |
1998年 | 8篇 |
1997年 | 7篇 |
1996年 | 8篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1992年 | 8篇 |
1991年 | 4篇 |
1990年 | 12篇 |
1989年 | 3篇 |
1987年 | 3篇 |
1986年 | 6篇 |
1985年 | 8篇 |
1984年 | 4篇 |
1983年 | 6篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1974年 | 4篇 |
1973年 | 5篇 |
1972年 | 2篇 |
1970年 | 4篇 |
1969年 | 2篇 |
排序方式: 共有1419条查询结果,搜索用时 0 毫秒
1.
Drug-resistance in Streptococcus pneumoniae isolates among Spanish middle aged and older adults with community-acquired pneumonia 总被引:1,自引:0,他引:1
Angel Vila-Corcoles Ferran Bejarano-Romero Elisabeth Salsench Olga Ochoa-Gondar Cinta de Diego Frederic Gomez-Bertomeu Xavier Raga-Luria Xavier Cliville-Guasch Victoria Arija 《BMC infectious diseases》2009,9(1):36
Background
Pneumococcal diseases remain a major cause of morbidity and mortality worldwide. Updated data on drug-resistance from different populations may be important to recognize changes in disease patterns. This study assessed current levels of penicilin resistance among Streptococcus Pneumoniae causing pneumonia in Spanish middle age and older adults. 相似文献2.
3.
Corticosteroid inhibition of the OKT3-induced cytokine-related syndrome--dosage and kinetics prerequisites 总被引:2,自引:0,他引:2
The data presented extend to a larger series of 27 consecutive renal allograft recipients treated prophylactically with OKT3 our previous observation that the acute OKT3-induced clinical syndrome is related to massive release in the circulation of some cytokines, among which are tumor necrosis factor and interferon gamma. In addition, a pilot randomized study was set up including 12 consecutive patients receiving high-dose corticosteroid treatment (0.5 g solumedrol) either before or at the same time as the first OKT3 injection. Results confirm that when corticosteroids are given in sufficient amount and, importantly, 1 hr before the first OKT3 injection, they significantly decrease the release of both tumor necrosis factor and interferon gamma. In addition, the pretreatment with corticosteroids may totally abolish the IL-2 release induced by OKT3. Given the key role the massive although transient cytokine release plays in determining the OKT3-induced acute syndrome, these results provide the biological basis supporting a precise kinetics of administration of high-dose corticosteroids to better decrease the severity of the clinical reaction. 相似文献
4.
5.
Plana M Garcia F Oxenius A Ortiz GM Lopez A Cruceta A Mestre G Fumero E Fagard C Sambeat MA Segura F Miró JM Arnedo M Lopalcos L Pumarola T Hirschel B Phillips RE Nixon DF Gallart T Gatell JM 《Journal of acquired immune deficiency syndromes (1999)》2004,36(3):791-799
OBJECTIVES: To analyze the dynamics of both HIV-1-specific CD4 and CD8 T-cell responses during structured treatment interruptions (STIs) in chronically HIV-1-infected (CHI) patients and to correlate them with the viral set point achieved. METHODS: Forty-five early-stage CHI patients who were on highly active antiretroviral therapy (HAART) for at least 1 year and underwent STI were included. Plasma viral load (VL), peripheral blood mononuclear cell (PBMC) lymphoproliferative (LPR) response to HIV p24 protein, and HIV-1 epitope-specific interferon-gammarelease from CD8 T cells were measured over a minimum study period of 2 years. RESULTS: VL set point during final STI was both significantly lower than, and positively correlated to, baseline VL (P < 0.0001: mean VL reduction 0.77 log10, and r = 0.42, P = 0.004, respectively). CD4 LPRs to p24 increased significantly (P = 0.001) between day 0 of the first STI cycle and 4th STI but decreased thereafter. VL set point during final STI was significantly and negatively correlated with LPRs to p24 at both 2nd STI and 4th STI. Nevertheless, at week 52, 12 weeks after the end of the last STI, LPRs were weak and transient in all patients and were not correlated with VL set point. Moreover, the magnitude and breadth of HIV-1-specific CD8 T-cell responses increased significantly (P < 0.0001) between day 0 and week 52. The largest increases occurred during the final STI. Even though VL reached set point by week 12 of the final STI, HIV-1-specific CD8 T-cell responses did not stabilize but rather increased until the end of the follow-up and did not correlate with plasma VL (r = 0.01, P = 0.88). CONCLUSIONS: STIs do not lead to control of viral replication in CHI patients, probably due to the fact that boosted CTL responses lack strong and durable helper T-cell responses. To reset the VL set point, new approaches that effectively augment and preserve helper T-cell responses should be investigated. 相似文献
6.
7.
8.
9.
10.
Chango A Potier De Courcy G Boisson F Guilland JC Barbé F Perrin MO Christidès JP Rabhi K Pfister M Galan P Hercberg S Nicolas JP 《The British journal of nutrition》2000,84(6):891-896
The 677cytosine mutation identified in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene has been frequently associated with an elevated plasma homocysteine concentration. The aim of the present study was to determine the impact of this MTHFR common mutation on plasma and erythrocyte folate (RCF) and plasma total homocysteine (tHcy) concentrations in healthy French adults. A cohort of 291 subjects living in the Paris area and participating in the Supplementation en Vitamines et Mineraux Antioxydants (SU.VI.MAX) study were analysed to assess the impact of MTHFR polymorphism 677C-->T on folate status and plasma tHcy concentration. The frequency of the mutant homozygote for 677C-->T polymorphism (677TT genotype) in the present cohort was 16.8%. There were significant differences in plasma tHcy between 677CC, 677CT and 677TT genotype groups. The RCF concentrations were significantly different between each genotype, the lowest levels being associated with the 677TT genotype. When segregated by gender, no differences in tHcy between homozygous 677TT, heterozygous 677CT and wild-type 677CC genotype groups in women were observed. The fasting tHcy in women was unrelated to the 677C-->T mutation. However, tHcy was significantly increased in men with the homozygous 677TT genotype. We also analysed the possible implication of a second new MTHFR polymorphism (1298A-->C) in subjects with mild hyperhomocysteinaemia (4th quartile of homocysteinaemia; tHcy >11.1 micromol/l). The polymorphism 1298A-->C did not have a notable effect on tHcy or on the RCF levels. Our observations confirm a relatively high frequency of the 677TT genotype in the French population. Women with this genotype did not show the same increase in tHcy observed in men. In the present study dietary folate intake was not measured. Thus, the interaction of dietary folate with the MTHFR genotype in the French population needs further study. 相似文献