全文获取类型
收费全文 | 13281篇 |
免费 | 682篇 |
国内免费 | 78篇 |
专业分类
耳鼻咽喉 | 77篇 |
儿科学 | 268篇 |
妇产科学 | 328篇 |
基础医学 | 1802篇 |
口腔科学 | 484篇 |
临床医学 | 1101篇 |
内科学 | 3692篇 |
皮肤病学 | 332篇 |
神经病学 | 1436篇 |
特种医学 | 322篇 |
外科学 | 1691篇 |
综合类 | 59篇 |
一般理论 | 2篇 |
预防医学 | 694篇 |
眼科学 | 190篇 |
药学 | 698篇 |
中国医学 | 40篇 |
肿瘤学 | 825篇 |
出版年
2024年 | 16篇 |
2023年 | 102篇 |
2022年 | 211篇 |
2021年 | 442篇 |
2020年 | 230篇 |
2019年 | 299篇 |
2018年 | 433篇 |
2017年 | 263篇 |
2016年 | 339篇 |
2015年 | 357篇 |
2014年 | 514篇 |
2013年 | 645篇 |
2012年 | 1077篇 |
2011年 | 1107篇 |
2010年 | 619篇 |
2009年 | 597篇 |
2008年 | 972篇 |
2007年 | 953篇 |
2006年 | 890篇 |
2005年 | 783篇 |
2004年 | 701篇 |
2003年 | 621篇 |
2002年 | 641篇 |
2001年 | 70篇 |
2000年 | 63篇 |
1999年 | 94篇 |
1998年 | 106篇 |
1997年 | 104篇 |
1996年 | 89篇 |
1995年 | 71篇 |
1994年 | 69篇 |
1993年 | 62篇 |
1992年 | 43篇 |
1991年 | 46篇 |
1990年 | 40篇 |
1989年 | 36篇 |
1988年 | 30篇 |
1987年 | 28篇 |
1986年 | 28篇 |
1985年 | 17篇 |
1984年 | 34篇 |
1983年 | 31篇 |
1982年 | 21篇 |
1981年 | 24篇 |
1980年 | 18篇 |
1979年 | 10篇 |
1978年 | 11篇 |
1977年 | 19篇 |
1976年 | 8篇 |
1974年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 14 毫秒
71.
72.
73.
Antonella Petrillo Roberta Fusco Paolo Vallone Salvatore Filice Vincenza Granata Teresa Petrosino Maria Rosaria Rubulotta Sergio Venanzio Setola Mauro Mattace Raso Francesca Maio Concetta Raiano Claudio Siani Maurizio Di Bonito Gerardo Botti 《The breast journal》2020,26(5):860-872
To compare diagnostic performance of contrast‐enhanced dual‐energy digital mammography (CEDM) and digital breast tomosynthesis (DBT) alone and in combination compared to 2D digital mammography (MX) and dynamic contrast‐enhanced MRI (DCE‐MRI) in women with breast lesions. We enrolled 100 consecutive patients with breast lesions (BIRADS 3‐5 at imaging or clinically suspicious). CEDM, DBT, and DCE‐MRI 2D were acquired. Synthetized MX was obtained by DBT. A total of 134 lesions were investigated on 111 breasts of 100 enrolled patients: 53 were histopathologically proven as benign and 81 as malignant. Nonparametric statistics and receiver operating characteristic (ROC) curve were performed. Two‐dimensional synthetized MX showed an area under ROC curve (AUC) of 0.764 (sensitivity 65%, specificity 80%), while AUC was of 0.845 (sensitivity 80%, specificity 82%) for DBT, of 0.879 (sensitivity 82%, specificity 80%) for CEDM, and of 0.892 (sensitivity 91%, specificity 84%) for CE‐MRI. DCE‐MRI determined an AUC of 0.934 (sensitivity 96%, specificity 88%). Combined CEDM with DBT findings, we obtained an AUC of 0.890 (sensitivity 89%, specificity 74%). A difference statistically significant was observed only between DCE‐MRI and CEDM (P = .03). DBT, CEDM, CEDM combined to tomosynthesis, and DCE‐MRI had a high ability to identify multifocal and bilateral lesions with a detection rate of 77%, 85%, 91%, and 95% respectively, while 2D synthetized MX had a detection rate for multifocal lesions of 56%. DBT and CEDM have superior diagnostic accuracy of 2D synthetized MX to identify and classify breast lesions, and CEDM combined with DBT has better diagnostic performance compared with DBT alone. The best results in terms of diagnostic performance were obtained by DCE‐MRI. Dynamic information obtained by time‐intensity curve including entire phase of contrast agent uptake allows a better detection and classification of breast lesions. 相似文献
74.
Elodie Montaudon Rania El Botty Sophie Vacher Olivier Das Adnan Naguez Sophie Chateau-Joubert Damien Treguer Ludmilla de Plater Leïla Zemoura Fariba Nmati Andr Nicolas Alain Chapelier Alain Livartowski Stefano Cairo Catherine Daniel Marie Brevet Elisabetta Marangoni Didier Meseure Sergio Roman-Roman Ivan Bieche Nicolas Girard Didier Decaudin 《Oncotarget》2021,12(8):859
Significant rational is available for specific targeting of PI3K/AKT/mTOR pathway in the treatment of non-small cell lung cancer (NSCLC). However, almost all clinical trials that have evaluated Pi3K pathway-based monotherapies/combinations did not observe an improvement of patient’s outcome. The aim of our study was therefore to define combination of treatment based on the determination of predictive markers of resistance to the mTORC1 inhibitor RAD001/Everolimus. An in vivo study showed high efficacy of RAD001 in NSCLC Patient-Derived Xenografts (PDXs). When looking at biomarkers of resistance by RT-PCR study, three genes were found to be highly expressed in resistant tumors, i.e., PLK1, CXCR4, and AXL. We have then focused our study on the combination of RAD001 + Volasertib, a PLK1 inhibitor, and observed a high antitumor activity of the combination in comparison to each monotherapy; similarly, a clear synergistic effect between the two compounds was found in an in vitro study. Pharmacodynamics study demonstrated that this synergy was due to (1) tumor vascularization decrease, increase of the HIF1 protein expression and decrease of the intracellular pH, and (2) decrease of the Carbonic Anhydrase 9 (CAIX) protein that could not correct intracellular acidosis. In conclusion, all these preclinical data strongly suggest that the inhibition of mTORC1 and PLK1 proteins may be a promising therapeutic approach for NSCLC patients. 相似文献
75.
76.
Whitehead GS Wang T DeGraff LM Card JW Lira SA Graham GJ Cook DN 《American journal of respiratory and critical care medicine》2007,175(3):243-249
RATIONALE: The D6 chemokine receptor can bind and scavenge several chemokines, including the T-helper 2 (Th2)-associated chemokines CCL17 and CCL22. Although D6 is constitutively expressed in the lung, its pulmonary function is unknown. OBJECTIVES: This study tested whether D6 regulates pulmonary chemokine levels, inflammation, or airway responsiveness during allergen-induced airway disease. METHODS: D6-deficient and genetically matched C57BL/6 mice were sensitized and challenged with ovalbumin. ELISA and flow cytometry were used to measure levels of cytokines and leukocytes, respectively. Mechanical ventilation was used to measure airway reactivity. RESULTS: The ability of D6 to diminish chemokine levels in the lung was chemokine concentration dependent. CCL17 and CCL22 were abundant in the airway, and their levels were attenuated by D6 when they were within a defined concentration range. By contrast, airway concentrations of CCL3, CCL5, and CCL11 were low and unaffected by D6. Allergen-challenged D6-deficient mice had more dendritic cells, T cells, and eosinophils in the lung parenchyma and more eosinophils in the airway than similarly challenged C57BL/6 mice. By contrast, D6-deficient mice had reduced airway responses to methacholine compared with C57BL/6 mice. Thus, D6 has opposing effects on inflammation and airway reactivity. CONCLUSIONS: The ability of D6 to scavenge chemokines in the lung is dependent on chemokine concentration. The absence of D6 increases inflammation, but reduces airway reactivity. These findings suggest that inhibiting D6 function might be a novel means to attenuate airway responses in individuals with allergic asthma. 相似文献
77.
Engraftment of Allogeneic Hematopoietic Progenitor Cells With Purine Analog-Containing Chemotherapy: Harnessing Graft-Versus-Leukemia Without Myeloablative Therapy 总被引:30,自引:48,他引:30
Giralt Sergio; Estey Elihu; Albitar Maher; van Besien Koen; Rondon Gabriela; Anderlini Paolo; O'Brien Susan; Khouri Issa; Gajewski James; Mehra Rakesh; Claxton David; Andersson Borje; Beran Miloslav; Przepiorka Donna; Koller Charles; Kornblau Steve; Korbling Martin; Keating Michael; Kantarjian Hagop; Champlin Richard 《Blood》1997,89(12):4531-4536
78.
González-Quevedo A García SG Concepción OF Freixas RS Sotolongo LQ Menéndez MC Sánchez MP Almirall IF Carriera RF Díaz ZH Menéndez K 《Clinical biochemistry》2011,44(2-3):154-159
ObjectivesTo investigate the occurrence of subclinical neurologic involvement in patients with essential hypertension employing serum biochemical markers.Design and methodsFifty patients with essential hypertension and 42 controls with no clinical evidence of neurological disease were recruited. Serum S100B protein and neuron specific enolase (NSE) were determined by employing immunoassay kits from CanAg Diagnostics AB (Sweden). Brain MRI and fundoscopic exploration were conducted.ResultsS-100B and NSE levels were significantly higher in hypertensive patients than in controls. In hypertensive patients, multivariate analysis revealed that NSE was independently associated with two variables expressing severity of hypertension: diastolic blood pressure and grade of retinopathy. Brain MRI studies demonstrated higher NSE levels in patients with more severe white matter lesions.ConclusionsRaised NSE levels are associated with a higher severity of hypertension and of white matter lesions, providing preliminary evidence that suggests the presence of silent brain damage in a subset of hypertensive patients. 相似文献
79.
Correction of metachromatic leukodystrophy in the mouse model by transplantation of genetically modified hematopoietic stem cells 总被引:9,自引:0,他引:9 下载免费PDF全文
Biffi A De Palma M Quattrini A Del Carro U Amadio S Visigalli I Sessa M Fasano S Brambilla R Marchesini S Bordignon C Naldini L 《The Journal of clinical investigation》2004,113(8):1118-1129
Gene-based delivery can establish a sustained supply of therapeutic proteins within the nervous system. For diseases characterized by extensive CNS and peripheral nervous system (PNS) involvement, widespread distribution of the exogenous gene may be required, a challenge to in vivo gene transfer strategies. Here, using lentiviral vectors (LVs), we efficiently transduced hematopoietic stem cells (HSCs) ex vivo and evaluated the potential of their progeny to target therapeutic genes to the CNS and PNS of transplanted mice and correct a neurodegenerative disorder, metachromatic leukodystrophy (MLD). We proved extensive repopulation of CNS microglia and PNS endoneurial macrophages by transgene-expressing cells. Intriguingly, recruitment of these HSC-derived cells was faster and more robust in MLD mice. By transplanting HSCs transduced with the arylsulfatase A gene, we fully reconstituted enzyme activity in the hematopoietic system of MLD mice and prevented the development of motor conduction impairment, learning and coordination deficits, and neuropathological abnormalities typical of the disease. Remarkably, ex vivo gene therapy had a significantly higher therapeutic impact than WT HSC transplantation, indicating a critical role for enzyme overexpression in the HSC progeny. These results indicate that transplantation of LV-transduced autologous HSCs represents a potentially efficacious therapeutic strategy for MLD and possibly other neurodegenerative disorders. 相似文献
80.
PP Mainenti D Iodice I Cozzolino S Segreto S Capece G Sica M Magliulo G Ciancia L Pace M Salvatore 《Clinical imaging》2012,36(5):559-567
To evaluate the tomographic features in differentiating benign from malignant splenic diseases, 54 patients with a cytohistological examination and a contrast-enhanced multidetector computed tomography (ce-MDCT) and/or positron emission tomography/computed tomography (PET/CT) were retrospectively selected. Significant associations were observed between ce-MDCT Pattern 3 (focal hyperdense lesion) and Pattern 4 (infarcts/cysts) as well as PET/CT Pattern 3 (focal photopenia/diffuse uptake相似文献