全文获取类型
收费全文 | 5031篇 |
免费 | 353篇 |
国内免费 | 44篇 |
专业分类
耳鼻咽喉 | 42篇 |
儿科学 | 107篇 |
妇产科学 | 134篇 |
基础医学 | 803篇 |
口腔科学 | 84篇 |
临床医学 | 427篇 |
内科学 | 1289篇 |
皮肤病学 | 88篇 |
神经病学 | 608篇 |
特种医学 | 113篇 |
外科学 | 455篇 |
综合类 | 8篇 |
一般理论 | 3篇 |
预防医学 | 294篇 |
眼科学 | 78篇 |
药学 | 426篇 |
中国医学 | 9篇 |
肿瘤学 | 460篇 |
出版年
2024年 | 2篇 |
2023年 | 48篇 |
2022年 | 92篇 |
2021年 | 178篇 |
2020年 | 111篇 |
2019年 | 149篇 |
2018年 | 152篇 |
2017年 | 114篇 |
2016年 | 167篇 |
2015年 | 163篇 |
2014年 | 192篇 |
2013年 | 283篇 |
2012年 | 396篇 |
2011年 | 397篇 |
2010年 | 231篇 |
2009年 | 190篇 |
2008年 | 360篇 |
2007年 | 360篇 |
2006年 | 301篇 |
2005年 | 336篇 |
2004年 | 321篇 |
2003年 | 261篇 |
2002年 | 256篇 |
2001年 | 33篇 |
2000年 | 20篇 |
1999年 | 29篇 |
1998年 | 42篇 |
1997年 | 45篇 |
1996年 | 28篇 |
1995年 | 38篇 |
1994年 | 24篇 |
1993年 | 15篇 |
1992年 | 11篇 |
1991年 | 9篇 |
1990年 | 9篇 |
1989年 | 12篇 |
1988年 | 6篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 8篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 4篇 |
排序方式: 共有5428条查询结果,搜索用时 31 毫秒
71.
Transcriptional regulation of human sodium/iodide symporter gene: a role for redox factor-1 总被引:11,自引:0,他引:11
Puppin C Arturi F Ferretti E Russo D Sacco R Tell G Damante G Filetti S 《Endocrinology》2004,145(3):1290-1293
72.
Busca A Lovisone E Aliberti S Locatelli F Serra A Scaravaglio P Omedè P Rossi G Cirillo D Barbui A Ghisetti V Dall'Omo AM Falda M 《Hematology (Amsterdam, Netherlands)》2003,8(5):303-311
Non-myeloablative stem cell transplantation (NMT) has been increasingly used in compromised patients who would otherwise have been unable to undergo allotransplant. There is little understanding of the kinetics of immune reconstitution and its influence on infective complications following NMT. The aim of present study was to evaluate lymphocyte subset reconstitution over the first 12 months post-transplant in 15 adult patients receiving NMT with comparison to that of 30 patients grafted with a conventional hemopoietic stem cell transplantation (HSCT). NMT recipients were conditioned with fludarabine-based conditioning regimens. Peripheral blood stem cell (PBSC) was the source of stem cells in 13 NMT recipients and in 24 conventional HSCT recipients. Absolute numbers of helper (CD4+) T cells, naive (CD4+ CD45RA+) and memory (CD4+ CD45RO+) T cells as well as suppressor (CD8+) T cells, CD19+ B cells and NK cells were comparable in the two groups at all time points after transplantation. A median value of 200 CD4+ T cells/microl was achieved at 2 months post-transplant by the NMT and HSCT recipients. The CD4:CD8 ratio remained severely depressed throughout the study period. Almost all CD4+ lymphocytes expressed CD45RO antigen in the both groups of patients B lymphocytes showed low counts throughout the entire study period in both groups. Bacteremia and CMV antigenemia occurred respectively in 13 and 36% of the patients in the NMT group and in 15 and 39% of the patients in the HSCT group. Our preliminary data indicate that patients receiving a NMT have a lymphocyte reconstitution similar to that observed in patients who received a conventional HSCT. The incidence of bacteremia and CMV infection were not significantly different between the groups. Nevertheless, due to the small sample size, these results should be considered suggestive rather than definitive. 相似文献
73.
Laura Castelnovo Antonio Tamburello Alfredo Lurati Eleonora Zaccara Maria Grazia Marrazza Micol Olivetti Nicola Mumoli Daniela Mastroiacovo Daniele Colombo Elisabetta Ricchiuti Paolo Vigano Faggioli Paola Antonino Mazzone 《Medicine》2021,100(1)
COVID-19 is causing a high influx of patients suffering from serious respiratory complications leading the necessity to find effective therapies. These patients seem to present with cytokine perturbation and high levels of IL6. Tocilizumab and sarilumab could be effective in this condition.We retrospectively collected data about 112 consecutive hospitalized in a single center.Fifty (IL6 group) treated with tocilizumab (8 mg/kg intravenously [IV], 2 infusions 12 hours apart) or sarilumab 400 mg IV once and 62 treated with the standard of care but not anti-cytokine drugs (CONTROL group).To determine whether anti-IL6 drugs are effective in improving prognosis and reducing hospitalization times and mortality in COVID-19 pneumonia.To date 84% (42/50) of IL6 group patients have already been discharged and only 2/50 are still recovered and intubated in intensive care. Six/fifty patients (12%) died: 5/6 due to severe respiratory failure within a framework of severe acute respiratory distress syndrome (ARDS), 1 suffered an acute myocardial infarction, and 1 died of massive pulmonary thromboembolism. There were no adverse treatment events or infectious complications. Compared to the CONTROL group they showed a lower mortality rate (12% versus 43%), for the same number of complications and days of hospitalization.Anti-IL6 drugs seem to be effective in the treatment of medium to severe forms of COVID-19 pneumonia reducing the risk of mortality due to multi-organ failure, acting at the systemic level and reducing inflammation levels and therefore microvascular complications. However, it is essential to identify the best time for treatment, which, if delayed, is rendered useless as well as counterproductive. Further studies and ongoing clinical trials will help us to better define patients eligible as candidates for more aggressive intervention. 相似文献
74.
Genetic abnormalities in adolescents and young adults with neuroblastoma: A report from the Italian Neuroblastoma Group 下载免费PDF全文
Katia Mazzocco PhD Raffaella Defferrari PhD Angela Rita Sementa MD Alberto Garaventa MD Luca Longo PhD Marilena De Mariano PhD Maria Rosaria Esposito PhD Francesca Negri PhD Davide Ircolò Elisabetta Viscardi MD Roberto Luksch MD Paolo D'Angelo MD Arcangelo Prete MD Aurora Castellano MD Paolo Massirio MD Giovanni Erminio PhD Anna Rita Gigliotti MD Gian Paolo Tonini PhD Massimo Conte MD 《Pediatric blood & cancer》2015,62(10):1725-1732
75.
Manunta P Iacoviello M Forleo C Messaggio E Hamlyn JM Lucarelli K Guida P Romito R De Tommasi E Bianchi G Rizzon P Pitzalis MV 《Journal of hypertension》2005,23(9):1677-1681
OBJECTIVE: Impaired diastolic function and left ventricular hypertrophy can occur early in the natural history of essential hypertension. High circulating levels of endogenous ouabain (EO) have been described in essential hypertension and have also been associated with left ventricular hypertrophy. The aim of this study was to investigate whether these cardiac modifications are related to plasma EO levels in the offspring of hypertensive families. METHODS: The study involved 41 subjects with (FAM+) and 45 subjects without (FAM-) a family history of hypertension. Arterial blood pressure, left ventricular geometry and function, and plasma EO levels were measured in each subject. RESULTS: Plasma EO levels were higher in the FAM+ subjects (221.5 +/- 10.95 versus 179.6 +/- 9.58 pmol/l, P = 0.004), and directly correlated with both systolic (r = 0.417, P < 0.0001) and diastolic blood pressure (r = 0.333, P = 0.002). Plasma EO was inversely related to an index of cardiac diastolic function determined as the ratio between the early and late peak flow velocity (r = -0.286, P = 0.012) and isovolumetric relaxation time (IVRT) (r = 0.32, P = 0.003). The IVRT was also significantly higher in FAM+, correlated with the IVRT (r = 0.32, P = 0.003). The IVRT was also significantly higher in FAM+, whereas the other echocardiographic parameters were similar to FAM-. CONCLUSIONS: Among the offspring of families with a positive history of hypertension, circulating EO levels and blood pressure are increased. Plasma EO levels are related to alterations of some indexes of diastolic heart function in these individuals. 相似文献
76.
Elisabetta Meacci Su-Chen Tsai Ronald Adamik Joel Moss Martha Vaughan 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(5):1745-1748
Cytohesin-1, a protein abundant in cells of the immune system, has been proposed to be a human homolog of the Saccharomyces cerevisiae Sec7 gene product, which is crucial in protein transport. More recently, the same protein has been reported to be a regulatory factor for the αLβ2 integrin in lymphocytes. Overexpression of human or yeast ADP-ribosylation factor (ARF) genes rescues yeast with Sec7 defects, restoring secretory pathway function. ARFs, 20-kDa guanine nucleotide-binding proteins initially identified by their ability to stimulate cholera toxin ADP-ribosyltransferase activity and now recognized as critical components in intracellular vesicular transport, exist in an inactive cytosolic form with GDP bound (ARF-GDP). Interaction with a guanine nucleotide-exchange protein (GEP) accelerates exchange of GDP for GTP, producing the active ARF-GTP. Both soluble and particulate GEPs have been described. To define better the interaction between ARF and Sec7-related proteins, effects of cytohesin-1, synthesized in Escherichia coli, on ARF activity were evaluated. Cytohesin-1 enhanced binding of 35S-labeled guanosine 5′-[γ-thio]triphosphate [35S]GTP[γS] or [3H]GDP to ARF purified from bovine brain (i.e., it appeared to function as an ARF-GEP). Addition of cytohesin-1 to ARF3 with [35S]GTP[γS] bound, accelerated [35S]GTP[γS] release to a similar degree in the presence of unlabeled GDP or GTP[γS] and to a lesser degree with GDP[βS]; release was negligible without added nucleotide. Cytohesin-1 also increased ARF1 binding to a Golgi fraction, but its effect was not inhibited by brefeldin A (BFA), a drug that reversibly inhibits Golgi function. In this regard, it differs from a recently reported BFA-sensitive ARF-GEP that contains a Sec7 domain. 相似文献
77.
78.
79.
Paola Forti Fabiola Maioli Elisabetta Magni Letizia Ragazzoni Roberto Piperno Marco Zoli Maura Coveri Gaetano Procaccianti 《Archives of physical medicine and rehabilitation》2018,99(3):477-483
Objective
To investigate whether oldest-old age (≥85y) is an independent predictor of exclusion from stroke rehabilitation.Design
Retrospective cohort study.Setting
Stroke unit (SU) of a tertiary hospital.Participants
Elderly patients (N=1055; aged 65–74y, n=230; aged 75–84y, n=432; aged ≥85y, n=393) who, between 2009 and 2012, were admitted to the SU with acute stroke and evaluated by a multiprofessional team for access to rehabilitation. The study excluded patients for whom rehabilitation was unnecessary or inappropriate.Interventions
Not applicable.Main Outcome Measures
Access to an early mobilization (EM) protocol during SU stay and subsequent access to postacute rehabilitation after SU discharge. Analyses were adjusted for prestroke and stroke-related characteristics.Results
32.2% of patients were excluded from EM. Multivariable-adjusted odds ratios (ORs) of EM exclusion were 1.30 (95% confidence interval [CI], .76–2.21) for ages 75 to 84 years and 2.07 (95% CI, 1.19–3.59) for ages ≥85 years compared with ages 65 to 74 years. Of 656 patients admitted to EM and who, at SU discharge, had not yet fully recovered their prestroke functional status, 18.4% were excluded from postacute rehabilitation. For patients able to walk unassisted at SU discharge, the probability of exclusion did not change across age groups. For patients unable to walk unassisted at SU discharge, ORs of exclusion from postacute rehabilitation were 3.74 (95% CI, 1.26–11.13) for ages 75 to 84 years and 9.15 (95% CI, 3.05–27.46) for ages ≥85 years compared with ages 65 to 74 years.Conclusions
Oldest-old age is an independent predictor of exclusion from stroke rehabilitation. 相似文献80.
Ettore Beghi Elisa Gervasoni Elisabetta Pupillo Elisa Bianchi Angelo Montesano Irene Aprile Michela Agostini Marco Rovaris Davide Cattaneo 《Archives of physical medicine and rehabilitation》2018,99(4):641-651