全文获取类型
收费全文 | 1808篇 |
免费 | 123篇 |
国内免费 | 52篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 79篇 |
妇产科学 | 36篇 |
基础医学 | 167篇 |
口腔科学 | 38篇 |
临床医学 | 240篇 |
内科学 | 428篇 |
皮肤病学 | 31篇 |
神经病学 | 217篇 |
特种医学 | 187篇 |
外科学 | 185篇 |
综合类 | 25篇 |
预防医学 | 101篇 |
眼科学 | 32篇 |
药学 | 109篇 |
1篇 | |
中国医学 | 10篇 |
肿瘤学 | 90篇 |
出版年
2023年 | 7篇 |
2022年 | 32篇 |
2021年 | 45篇 |
2020年 | 29篇 |
2019年 | 41篇 |
2018年 | 61篇 |
2017年 | 51篇 |
2016年 | 64篇 |
2015年 | 47篇 |
2014年 | 79篇 |
2013年 | 88篇 |
2012年 | 51篇 |
2011年 | 58篇 |
2010年 | 77篇 |
2009年 | 108篇 |
2008年 | 60篇 |
2007年 | 77篇 |
2006年 | 42篇 |
2005年 | 63篇 |
2004年 | 34篇 |
2003年 | 26篇 |
2002年 | 14篇 |
2001年 | 38篇 |
2000年 | 25篇 |
1999年 | 34篇 |
1998年 | 89篇 |
1997年 | 87篇 |
1996年 | 61篇 |
1995年 | 56篇 |
1994年 | 38篇 |
1993年 | 46篇 |
1992年 | 20篇 |
1991年 | 16篇 |
1990年 | 23篇 |
1989年 | 37篇 |
1988年 | 29篇 |
1987年 | 35篇 |
1986年 | 21篇 |
1985年 | 27篇 |
1984年 | 21篇 |
1983年 | 16篇 |
1982年 | 12篇 |
1981年 | 12篇 |
1980年 | 11篇 |
1979年 | 4篇 |
1978年 | 16篇 |
1977年 | 23篇 |
1976年 | 8篇 |
1975年 | 5篇 |
1964年 | 3篇 |
排序方式: 共有1983条查询结果,搜索用时 31 毫秒
41.
42.
Brandon A. Mahal David R. Ziehr Ayal A. Aizer Andrew S. Hyatt Jesse D. Sammon Marianne Schmid Toni K. Choueiri Jim C. Hu Christopher J. Sweeney Clair J. Beard Anthony V. D׳Amico Neil E. Martin Christopher Lathan Simon P. Kim Quoc-Dien Trinh Paul L. Nguyen 《Urologic oncology》2014,32(8):1285-1291
ObjectivesTreating high-risk prostate cancer (CaP) with definitive therapy improves survival. We evaluated whether having health insurance reduces racial disparities in the use of definitive therapy for high-risk CaP.Materials and methodsThe Surveillance, Epidemiology, and End Results Program was used to identify 70,006 men with localized high-risk CaP (prostate-specific antigen level >20 ng/ml or Gleason score 8–10 or stage>cT3a) diagnosed from 2007 to 2010. We used multivariable logistic regression to analyze the 64,277 patients with complete data to determine the factors associated with receipt of definitive therapy.ResultsCompared with white men, African American (AA) men were significantly less likely to receive definitive treatment (adjusted odds ratio [AOR] = 0.60; 95% CI: 0.56–0.64; P<0.001) after adjusting for sociodemographics and known CaP prognostic factors. There was a significant interaction between race and insurance status (Pinteraction = 0.01) such that insurance coverage was associated with a reduction in racial disparity between AA and white patients regarding receipt of definitive therapy. Specifically, the AOR for definitive treatment for AA vs. white was 0.38 (95% CI: 0.27–0.54, P<0.001) among uninsured men, whereas the AOR was 0.62 (95% CI: 0.57–0.66, P<0.001) among insured men.ConclusionsAA men with high-risk CaP were significantly less likely to receive potentially life-saving definitive treatment when compared with white men. Having health insurance was associated with a reduction in this racial treatment disparity, suggesting that expansion of health insurance coverage may help reduce racial disparities in the management of aggressive cancers. 相似文献
43.
Mona Jabbour MD Martin H Osmond MD CM Terry P Klassen MD MSc 《Annals of emergency medicine》1996,28(6):690-698
Study objective: To determine the effectiveness of life support courses for health care providers on the basis of one of three outcomes: (1) patient mortality and morbidity, (2) retention of knowledge or skills, and (3) change in practice behavior. Methods: English-language articles from 1975 to 1992 were identified through MEDLINE and ERIC searches, bibliographies of articles, and current abstracts. Studies were considered relevant if they included a study population of life support providers, an intervention of any of the identified life support courses, and assessment of at least one of the three listed outcomes. Relevant studies were selected and validity scores were assigned to them by agreement of two independent reviewers, using a structured form to assess validity. Data on setting, methods, participants, intervention, and outcomes were then abstracted and verified. Results: Seventeen of 67 identified studies pertaining to life support courses met the inclusion criteria. (1) All three mortality and morbidity studies indicated a positive impact, with an overall odds ratio of .28 (95% confidence interval [CI], .22 to .37). (2) No net increase in scores was found in 5 of 8 studies of retention of knowledge and in 8 of 9 studies of skills retention. Two of three studies reporting refresher activities yielded positive effects on knowledge retention. Outcomes were not significantly different between groups taught with modular or didactic techniques. (3) Studies assessing behavioral outcome were methodologically weak. Conclusion: Among providers, retention of knowledge and skills acquired by participation in support courses is poor. However, refresher activities increase knowledge retention. Modular courses are as good as lectures for learning course material. There is evidence that use of the Advanced Trauma Life Support course has decreased mortality and morbidity. Further studies of patient outcome and provider behaviors are warranted. [Jabbour M, Osmond MH, Klassen TP: Life support courses: Are they effective? Ann Emerg Med December 1996;28:690-698.] 相似文献
44.
45.
Linda Beneforti Erica Dander Silvia Bresolin Clara Bueno Denise Acunzo Mayla Bertagna Anthony Ford Bernhard Gentner Geertruy te Kronnie Patrizia Vergani Pablo Menéndez Andrea Biondi Giovanna D’Amico Chiara Palmi Giovanni Cazzaniga 《British journal of haematology》2020,190(2):262-273
ETV6-RUNX1 (E/R) fusion gene, arising in utero from translocation t(12;21)(p13:q22), is the most frequent alteration in childhood acute lymphoblastic leukemia (ALL). However, E/R is insufficient to cause overt leukemia since it generates a clinically silent pre-leukemic clone which persists in the bone marrow but fails to out-compete normal progenitors. Conversely, pre-leukemic cells show increased susceptibility to transformation following additional genetic insults. Infections/inflammation are the most accredited triggers for mutations accumulation and leukemic transformation in E/R+ pre-leukemic cells. However, precisely how E/R and inflammation interact in promoting leukemia is still poorly understood. Here we demonstrate that IL6/TNFα/ILβ pro-inflammatory cytokines cooperate with BM-MSC in promoting the emergence of E/R+ Ba/F3 over their normal counterparts by differentially affecting their proliferation and survival. Moreover, IL6/TNFα/ILβ-stimulated BM-MSC strongly attract E/R+ Ba/F3 in a CXCR2-dependent manner. Interestingly, E/R-expressing human CD34+IL7R+ progenitors, a putative population for leukemia initiation during development, were preserved in the presence of BM-MSC and IL6/TNFα/ILβ compared to their normal counterparts. Finally, the extent of DNA damage increases within the inflamed niche in both control and E/R-expressing Ba/F3, potentially leading to transformation in the apoptosis-resistant pre-leukemic clone. Overall, our data provide new mechanistic insights into childhood ALL pathogenesis. 相似文献
46.
Carlos O. Weiss MD Ravi Varadhan PhD Milo A. Puhan MD PhD Andrew Vickers PhD Karen Bandeen-Roche PhD MS Cynthia M. Boyd MD MPH David M. Kent MD CM MSc 《Journal of general internal medicine》2014,29(4):653-660
Most people with a chronic disease actually have more than one, a condition known as multimorbidity. Despite this, the evidence base to prevent adverse disease outcomes has taken a disease-specific approach. Drawing on a conference, Improving Guidelines for Multimorbid Patients, the goal of this paper is to identify challenges to the generation of evidence to support the care of people with multimorbidity and to make recommendations for improvement. We identified three broad categories of challenges: 1) challenges to defining and measuring multimorbidity; 2) challenges related to the effects of multimorbidity on study design, implementation and analysis; and 3) challenges inherent in studying heterogeneity of treatment effects in patients with differing comorbid conditions. We propose a set of recommendations for consideration by investigators and others (reviewers, editors, funding agencies, policymaking organizations) involved in the creation of evidence for this common type of person that address each of these challenges. The recommendations reflect a general approach that emphasizes broader inclusion (recruitment and retention) of patients with multimorbidity, coupled with more rigorous efforts to measure comorbidity and comorbidity burden and the influence of multimorbidity on outcomes and the effects of therapy. More rigorous examination of heterogeneity of treatment effects requires careful attention to prioritizing the most important comorbid-related questions, and also requires studies that provide greater statistical power than conventional trials have provided. Relatively modest changes in the orientation of current research along these lines can be helpful in pointing to and partially addressing selected knowledge gaps. However, producing a robust evidence base to support patient-centered decision making in complex individuals with multimorbidity, exposed to many different combinations of potentially interacting factors that can modify the risks and benefits of therapies, is likely to require a clinical research enterprise fundamentally restructured to be more fully integrated with routine clinical practice. 相似文献
47.
48.
Sebastiano Ettore Spoto Giuseppe Paladini Francesco Caridi Vincenza Crupi Sebastiano DAmico Domenico Majolino Valentina Venuti 《Materials》2022,15(3)
Plasters and mortars of the Church of the Annunciation (Tortorici, Sicily) were characterized, for the first time, both at the elemental and molecular levels, by means of portable X-ray fluorescence (XRF) and Raman spectroscopy, to achieve information on the “state of health” of the whole structure. The understanding of their degradation mechanisms and the identification of consequent degradation patterns can define the environmental factors responsible for interpreting the potential pathological forms that can impact the general building vulnerability. In this sense, the results obtained in this article provide relevant information to identify and address both the characterization of building materials and the fundamental causes of their deterioration. At the same time, if coupled with the attempt to supply a chronological order of the major restoration interventions carried out on the investigated site, they provide new insights to calibrate the models for building vulnerability studies. 相似文献
49.
D’Amico Randy S. Khatri Deepak Reichman Noah Patel Nitesh V. Wong Tamika Fralin Sherese R. Li Mona Ellis Jason A. Ortiz Rafael Langer David J. Boockvar John A. 《Journal of neuro-oncology》2020,147(2):261-278
Journal of Neuro-Oncology - Intra-arterial (IA) delivery of therapeutic agents across the blood-brain barrier (BBB) is an evolving strategy which enables the distribution of high concentration... 相似文献
50.
Alessandra DAmico Elena Cavarretta Chiara Fossati Paolo Borrione Fabio Pigozzi Giacomo Frati Sebastiano Sciarretta Vincenzo Costa Fabrizio De Grandis Antonia Nigro Mariangela Peruzzi Fabio Miraldi Wael Saade Antonella Calogero Paolo Rosa Gioacchino Galardo Lorenzo Loffredo Pasquale Pignatelli Cristina Nocella Roberto Carnevale 《Nutrients》2022,14(8)
Mechanisms of exercise-induced muscle injury with etiopathogenesis and its consequences have been described; however, the impact of different intensities of exercise on the mechanisms of muscular injury development is not well understood. The aim of this study was to exploit the relationship between platelet activation, oxidative stress and muscular injuries induced by physical exercise in elite football players compared to amateur athletes. Oxidant/antioxidant status, platelet activation and markers of muscle damage were evaluated in 23 elite football players and 23 amateur athletes. Compared to amateurs, elite football players showed lower antioxidant capacity and higher oxidative stress paralleled by increased platelet activation and muscle damage markers. Simple linear regression analysis showed that sNOX2-dp and H2O2, sCD40L and PDGF-bb were associated with a significant increase in muscle damage biomarkers. In vitro studies also showed that plasma obtained from elite athletes increased oxidative stress and muscle damage in human skeletal muscle myoblasts cell line compared to amateurs’ plasma, an effect blunted by the NOX2 inhibitor or by the cell treatment with cocoa-derived polyphenols. These results indicate that platelet activation increased muscular injuries induced by oxidative stress. Moreover, NOX2 inhibition and polyphenol extracts treatment positively modulates redox status and reduce exercise-induced muscular injury. 相似文献