全文获取类型
收费全文 | 6718篇 |
免费 | 304篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 59篇 |
儿科学 | 142篇 |
妇产科学 | 112篇 |
基础医学 | 803篇 |
口腔科学 | 95篇 |
临床医学 | 757篇 |
内科学 | 1744篇 |
皮肤病学 | 186篇 |
神经病学 | 564篇 |
特种医学 | 93篇 |
外科学 | 935篇 |
综合类 | 38篇 |
一般理论 | 2篇 |
预防医学 | 548篇 |
眼科学 | 106篇 |
药学 | 465篇 |
中国医学 | 20篇 |
肿瘤学 | 379篇 |
出版年
2024年 | 4篇 |
2023年 | 41篇 |
2022年 | 28篇 |
2021年 | 169篇 |
2020年 | 96篇 |
2019年 | 192篇 |
2018年 | 301篇 |
2017年 | 164篇 |
2016年 | 176篇 |
2015年 | 206篇 |
2014年 | 183篇 |
2013年 | 298篇 |
2012年 | 592篇 |
2011年 | 635篇 |
2010年 | 309篇 |
2009年 | 222篇 |
2008年 | 513篇 |
2007年 | 528篇 |
2006年 | 479篇 |
2005年 | 458篇 |
2004年 | 413篇 |
2003年 | 406篇 |
2002年 | 372篇 |
2001年 | 22篇 |
2000年 | 20篇 |
1999年 | 19篇 |
1998年 | 34篇 |
1997年 | 18篇 |
1996年 | 17篇 |
1995年 | 13篇 |
1994年 | 8篇 |
1993年 | 16篇 |
1992年 | 13篇 |
1991年 | 8篇 |
1990年 | 5篇 |
1988年 | 3篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 11篇 |
1981年 | 7篇 |
1980年 | 6篇 |
1979年 | 2篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1973年 | 2篇 |
1970年 | 2篇 |
排序方式: 共有7048条查询结果,搜索用时 15 毫秒
81.
82.
Flores-Rendón AR González-González JA García-Compean D Maldonado-Garza HJ Garza-Galindo AA 《Annals of hepatology》2008,7(3):230-234
Aim: The Child Pugh and MELD are good methods for predicting mortality in patients with chronic liver disease. We investigated their performance as risk factors for failure to control bleeding, in-hospital overall mortality and death related to esophageal variceal bleeding episodes. Methods: From a previous collected database, 212 cirrhotic patients with variceal bleeding admitted to our hospital were studied. The predictive capability of Child Pugh and MELD scores were compared using c statistics. Results: The Child-Pugh and MELD scores showed marginal capability for predicting failure to control bleeding (the area under receiver operating characteristics curve (AUROC) values were < 0.70 for both). The AUROC values for predicting inhospital overall mortality of Child-Pugh and MELD score were similar: 0.809 (CI 95%, 0.710 - 0.907) and 0.88 (CI 95% 0.77-0.99,) respectively. There was no significant difference between them (p > 0.05). The AU-ROC value of MELD for predicting mortality related to variceal bleeding was higher than the Child-Pugh score: 0.905 (CI 95% 0.801-1.00) vs 0.794 (CI 95% 0.676 - 0.913) respectively (p < 0.05). Conclusions: MELD and Child-Pugh were not efficacious scores for predicting failure to control bleeding. The Child-Pugh and MELD scores had similar capability for predicting in-hospital overall mortality. Nevertheless, MELD was significantly better than Child-Pugh score for predicting in-hospital mortality related to variceal bleeding. 相似文献
83.
José Miguel Baena-Díez Isaac Subirana Rafael Ramos Agustín Gómez de la Cámara Roberto Elosua Joan Vila Alejandro Marín-Ibáñez María Jesús Guembe Fernando Rigo María José Tormo-Díaz Conchi Moreno-Iribas Joan Josep Cabré Antonio Segura José Lapetra Miquel Quesada María José Medrano Paulino González-Diego Guillem Frontera Jaume Marrugat 《Revista espa?ola de cardiología》2018,71(4):274-282
Introduction and objectives
To assess the validity of the original low-risk SCORE function without and with high-density lipoprotein cholesterol and SCORE calibrated to the Spanish population.Methods
Pooled analysis with individual data from 12 Spanish population-based cohort studies. We included 30 919 individuals aged 40 to 64 years with no history of cardiovascular disease at baseline, who were followed up for 10 years for the causes of death included in the SCORE project. The validity of the risk functions was analyzed with the area under the ROC curve (discrimination) and the Hosmer-Lemeshow test (calibration), respectively.Results
Follow-up comprised 286 105 persons/y. Ten-year cardiovascular mortality was 0.6%. The ratio between estimated/observed cases ranged from 9.1, 6.5, and 9.1 in men and 3.3, 1.3, and 1.9 in women with original low-risk SCORE risk function without and with high-density lipoprotein cholesterol and calibrated SCORE, respectively; differences were statistically significant with the Hosmer-Lemeshow test between predicted and observed mortality with SCORE (P < .001 in both sexes and with all functions). The area under the ROC curve with the original SCORE was 0.68 in men and 0.69 in women.Conclusions
All versions of the SCORE functions available in Spain significantly overestimate the cardiovascular mortality observed in the Spanish population. Despite the acceptable discrimination capacity, prediction of the number of fatal cardiovascular events (calibration) was significantly inaccurate.Full English text available from:www.revespcardiol.org/en 相似文献84.
Luis M. Jara Pilar Cortés Germán Bou Jordi Barbé Jesús Aranda 《Antimicrobial agents and chemotherapy》2015,59(7):4318-4320
The effect of antimicrobials on SOS-mediated mutagenesis induction depends on the bacterial species and the antimicrobial group. In this work, we studied the effect of different families of antimicrobial agents used in clinical therapy against Acinetobacter baumannii in the induction of mutagenesis in this multiresistant Gram-negative pathogen. The data showed that ciprofloxacin and tetracycline induce SOS-mediated mutagenesis, whereas colistin and meropenem, which are extensively used in clinical therapy, do not. 相似文献
85.
Daniel Mayorga-Vega Pablo Aguilar-Soto Jesús Viciana 《Journal of Sports Science and Medicine》2015,14(3):536-547
The main purpose of the present meta-analysis was to examine the criterion-related validity of the 20-m shuttle run test for estimating cardiorespiratory fitness. Relevant studies were searched from twelve electronic databases up to December 2014, as well as from several alternative modes of searching. The Hunter-Schmidt’s psychometric meta-analysis approach was conducted to estimate the population criterion-related validity of the 20-m shuttle run test. From 57 studies that were included in the present meta-analysis, a total of 78 correlation values were analyzed. The overall results showed that the performance score of the 20-m shuttle run test had a moderate-to-high criterion-related validity for estimating maximum oxygen uptake (rp = 0.66-0.84), being higher when other variables (e.g. sex, age or body mass) were used (rp = 0.78-0.95). The present meta-analysis also showed that the criterion-related validity of Léger’s protocol was statistically higher for adults (rp = 0.94, 0.87-1.00) than for children (rp = 0.78, 0.72-0.85). However, sex and maximum oxygen uptake level do not seem to affect the criterion-related validity values. When an individual’s maximum oxygen uptake attained during a laboratory-based test is not feasible, the 20-m shuttle run test seems to be a useful alternative for estimating cardiorespiratory fitness. In adults the performance score only seems to be a strong estimator of cardiorespiratory fitness, in contrast among children the performance score should be combined with other variables. Nevertheless, as in the application of any physical fitness field test, evaluators must be aware that the performance score of the 20-m shuttle run test is simply an estimation and not a direct measure of cardiorespiratory fitness.
Key points
- Overall the 20-m shuttle run test has a moderate-to-high mean criterion-related validity for estimating cardiorespiratory fitness.
- The criterion-related validity of the 20-m shuttle run test is significantly higher for adults than for children. However, when the performance score is combined with other variables, the criterion-related validity value increases considerably among children.
- Sex and maximum oxygen uptake level of individuals seem not to affect the criterion-related validity of the 20-m shuttle run test.
- When individuals’ maximum oxygen uptake attained during a laboratory-based test is not feasible, the 20-m shuttle run test seems to be a useful alternative for estimating cardiorespiratory fitness.
86.
87.
Jes S. Lindholt M.D. Ph.D. Jan Møller Eskild W. Henneberg M.D. Cand Scient 《The International journal of angiology》2002,11(2):95-98
To study the possible role of homocysteine in aneurysmatic progression, in 1994, 112 of 141 male patients with abdominal aortic aneurysm (AAA) diagnosed by population screening were interviewed and examined. Creatinine clearance estimated and total plasma homocysteine (P-tHcy) was measured by gas chromatography-mass spectrometry. Of the 112 cases, 99 were followed with annual ultrasonography and blood pressure measurements for 1–5 years (mean 2.5 years). The mean creatinine clearance was 70.8+/-23.1 ml/min, while the mean P-tHcy was 16.0+/-10.6 mmol/l, significantly increased compared with an age- and sex-matched reference population (P<0.01). However, no trend of correlation with AAA size or aneurysmal progression was found concerning creatinine clearance and homocysteine level. There were still no trend after adjustment for age, smoking, diastolic blood pressure, and initial ankle blood pressure index. However, the homocysteine level was positively correlated with decreasing creatinine clearance (r=0.36,P<0.01), and this correlation was still present after the same adjustments. A large proportion of men with AAA have mild hyperhomocysteinemia; this does not influence aneurysmal progression and may be due to coexisting impaired renal function. The finding might explain why prospective and intervention studies cannot prove for certain that hyperhomocysteinemia influences atherosclerotic progression, or that treatment is beneficial. 相似文献
88.
An anti-CD45RO immunotoxin kills latently infected human immunodeficiency virus (HIV) CD4 T cells in the blood of HIV-positive persons. 总被引:2,自引:0,他引:2
Jesús Saavedra-Lozano Cynthia McCoig Jinbo Xu Yanying Cao Philip Keiser Victor Ghetie Robert F Siliciano Janet D Siliciano Louis J Picker Octavio Ramilo Ellen S Vitetta 《The Journal of infectious diseases》2002,185(3):306-314
Highly active antiretroviral therapy has decreased the morbidity and mortality of human immunodeficiency virus (HIV) infection, but latently infected cells remain for prolonged periods. CD4(+) CD45RO(+) T cells are a major latent virus reservoir in HIV-infected persons. Replication-competent, latently HIV-infected T cells can be generated in vitro by infecting peripheral blood mononuclear cells with HIV and then eliminating the HIV-producing cells with an anti-CD25 immunotoxin (IT). The CD25(-) latently infected cells then can be eliminated with an anti-CD45RO IT. This study determined whether this IT also could kill latently infected CD4 T cells from HIV-infected persons with or without detectable plasma viremia. The results show that ex vivo treatment of cells from HIV-positive persons by anti-CD45RO IT reduces the frequency of both productively and latently infected cells. In contrast, CD4(+) CD45RA(+) naive T cells and a proportion of CD4(+) CD45RO(lo) memory T cells are spared. 相似文献
89.
MICA rather than MICB,TNFA, or HLA-DRB1 is associated with susceptibility to psoriatic arthritis 总被引:2,自引:0,他引:2
González S Martínez-Borra J López-Vázquez A García-Fernández S Torre-Alonso JC López-Larrea C 《The Journal of rheumatology》2002,29(5):973-978
OBJECTIVE: To analyze the genetic contribution of HLA in development of psoriatic arthritis (PsA) and to study whether MICA is primarily associated with PsA or whether its association is secondary to linkage disequilibrium with centromeric genes, such as MICB, TNFA, or HLA-DRB1. METHODS: DNA samples from 81 Spanish patients with PsA and 110 healthy controls were examined by polymerase chain reaction (PCR) sequence-specific primers to type HLA-Cw and HLA-DRB1, PCR sequence-specific oligonucleotides to determine HLA-B, and PCR restriction fragment length polymorphism for tumor necrosis factor-alpha promoter polymorphisms at positions -238 and -308. Analysis of microsatellite polymorphisms in the transmembrane region of MICA and in intron 1 of MICB was also carried out. RESULTS: HLA-Cw*0602 was significantly increased in PsA [60% vs 17%; p(c) < 0.00002, OR 7.33, etiological fraction (EF) 0.52]. MICA-A9 (60% vs 30%; p(c) = 0.0002, OR 3.57, EF 0.43) and the microsatellite MICB-CA-22 allele (23% vs 7%; p(c) = 0.028, OR 3.9, EF 0.17) were also significantly increased in PsA. MICA-A9 was in linkage disequilibrium with MICB-CA-22 (delta = 0.6). The association of MICA-A9 was independent of MICB-CA-22 and Cw*0602, since it was also associated in MICB-CA-22 negative (p(c) = 0.0015, OR 2.96, EF 0.34) and in Cw*0602 negative patients (p(c) = 0.034, OR 2.83, EF 0.34). TNFA and DRB I alleles were not significantly associated with PsA. CONCLUSION: Cw*0602 and MICA-A9 appear to be the strongest genetic susceptibility factors for PsA. However, MICA-A9 was associated independently of Cw6. HLA-B alleles and MICB-CA22 are associated secondarily to linkage with MICA. TNFA and HLA-DRB1 were not associated with PsA susceptibility, and our data suggest that their reported association may only reflect the linkage disequilibrium with MICA-A9 among the different populations studied. 相似文献
90.
Juan M García-Lechuz Oscar Cuevas-Lobato Susana Hernángomez Ana Hermida Jesús Guinea Mercedes Marín Teresa Peláez Emilio Bouza 《International journal of infectious diseases》2002,6(1):78-82
OBJECTIVES: To understand the role of Gemella species as a pathogen causing extra-abdominal infections in the Hospital General Universitario Gregorio Mara?ón. MATERIALS AND METHODS: Between 1994 and 1998, one or more isolates of Gemella sp. were found in 128 patients. The 113 patients with isolates from nonsignificant specimens or representing intra-abdominal infections were excluded. The clinical records of the remaining 15 patients were reviewed as well as the more recent literature. RESULTS: Mean age of patients was 41 years. The underlying conditions most frequently noted were intravenous drug users (n=6; 3 positive for human immunodeficiency virus), alcoholism (n=2), cardiovascular disease (n=2), chronic lung disease (n=2), diabetes (n=1), kidney transplant (n=1). The extra-abdominal infections were skin and soft tissue abscess (n=5), empyema (n=4), brain abscess (n=2), primary bacteremia (n=1), lung abscess (n=1), septic thrombophlebitis (n=1), complicated urinary tract infection (n=1). The infection was monomicrobial in six and polymicrobial in nine cases. Surgical drainage and betalactam antibiotics were used. The outcome was favorable in almost all cases. CONCLUSIONS: Gemella sp. should be included as a cause of localized soft-tissue abscesses, empyema, and bloodstream infection. No case of infective endocarditis was found. Although it is susceptible to several antibiotics, Gemella sp. requires a careful microbiologic diagnosis and a subtle clinical interpretation. 相似文献