全文获取类型
收费全文 | 5248篇 |
免费 | 425篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 131篇 |
儿科学 | 136篇 |
妇产科学 | 57篇 |
基础医学 | 698篇 |
口腔科学 | 74篇 |
临床医学 | 690篇 |
内科学 | 974篇 |
皮肤病学 | 40篇 |
神经病学 | 593篇 |
特种医学 | 127篇 |
外科学 | 467篇 |
综合类 | 83篇 |
一般理论 | 3篇 |
预防医学 | 740篇 |
眼科学 | 97篇 |
药学 | 401篇 |
中国医学 | 22篇 |
肿瘤学 | 345篇 |
出版年
2023年 | 35篇 |
2022年 | 48篇 |
2021年 | 121篇 |
2020年 | 83篇 |
2019年 | 110篇 |
2018年 | 144篇 |
2017年 | 118篇 |
2016年 | 122篇 |
2015年 | 123篇 |
2014年 | 173篇 |
2013年 | 256篇 |
2012年 | 438篇 |
2011年 | 396篇 |
2010年 | 197篇 |
2009年 | 169篇 |
2008年 | 329篇 |
2007年 | 350篇 |
2006年 | 300篇 |
2005年 | 319篇 |
2004年 | 326篇 |
2003年 | 253篇 |
2002年 | 250篇 |
2001年 | 70篇 |
2000年 | 60篇 |
1999年 | 63篇 |
1998年 | 60篇 |
1997年 | 45篇 |
1996年 | 29篇 |
1995年 | 28篇 |
1994年 | 47篇 |
1993年 | 28篇 |
1992年 | 29篇 |
1991年 | 44篇 |
1990年 | 40篇 |
1989年 | 36篇 |
1988年 | 49篇 |
1987年 | 41篇 |
1986年 | 41篇 |
1985年 | 25篇 |
1984年 | 33篇 |
1983年 | 18篇 |
1982年 | 23篇 |
1981年 | 13篇 |
1979年 | 18篇 |
1978年 | 15篇 |
1977年 | 15篇 |
1974年 | 20篇 |
1972年 | 13篇 |
1971年 | 13篇 |
1969年 | 11篇 |
排序方式: 共有5678条查询结果,搜索用时 31 毫秒
1.
2.
3.
Stress Testing Versus CT Angiography in Patients With Diabetes and Suspected Coronary Artery Disease
Abhinav Sharma Adrian Coles Nishant K. Sekaran Neha J. Pagidipati Michael T. Lu Daniel B. Mark Kerry L. Lee Hussein R. Al-Khalidi Udo Hoffmann Pamela S. Douglas 《Journal of the American College of Cardiology》2019,73(8):893-902
Background
The optimal noninvasive test (NIT) for patients with diabetes and stable symptoms of coronary artery disease (CAD) is unknown.Objectives
The purpose of this study was to assess whether a diagnostic strategy based on coronary computed tomographic angiography (CTA) is superior to functional stress testing in reducing adverse cardiovascular (CV) outcomes (CV death or myocardial infarction [MI]) among symptomatic patients with diabetes.Methods
PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) was a randomized trial evaluating an initial strategy of CTA versus functional testing in stable outpatients with symptoms suggestive of CAD. The study compared CV outcomes in patients with diabetes (n = 1,908 [21%]) and without diabetes (n = 7,058 [79%]) based on their randomization to CTA or functional testing.Results
Patients with diabetes (vs. without) were similar in age (median 61 years vs. 60 years) and sex (female 54% vs. 52%) but had a greater burden of CV comorbidities. Patients with diabetes who underwent CTA had a lower risk of CV death/MI compared with functional stress testing (CTA: 1.1% [10 of 936] vs. stress testing: 2.6% [25 of 972]; adjusted hazard ratio: 0.38; 95% confidence interval: 0.18 to 0.79; p = 0.01). There was no significant difference in nondiabetic patients (CTA: 1.4% [50 of 3,564] vs. stress testing: 1.3% [45 of 3,494]; adjusted hazard ratio: 1.03; 95% confidence interval: 0.69 to 1.54; p = 0.887; interaction term for diabetes p value = 0.02).Conclusions
In diabetic patients presenting with stable chest pain, a CTA strategy resulted in fewer adverse CV outcomes than a functional testing strategy. CTA may be considered as the initial diagnostic strategy in this subgroup. (PROspective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550) 相似文献4.
Jennifer C. Sasaki Ashley Allemang Steven M. Bryce Laura Custer Kerry L. Dearfield Yasmin Dietz Azeddine Elhajouji Patricia A. Escobar Albert J. Fornace Jr Roland Froetschl Sheila Galloway Ulrike Hemmann Giel Hendriks Heng-Hong Li Mirjam Luijten Gladys Ouedraogo Lauren Peel Stefan Pfuhler Daniel J. Roberts Véronique Thybaud Jan van Benthem Carole L. Yauk Maik Schuler 《Environmental and molecular mutagenesis》2020,61(1):114-134
In May 2017, the Health and Environmental Sciences Institute's Genetic Toxicology Technical Committee hosted a workshop to discuss whether mode of action (MOA) investigation is enhanced through the application of the adverse outcome pathway (AOP) framework. As AOPs are a relatively new approach in genetic toxicology, this report describes how AOPs could be harnessed to advance MOA analysis of genotoxicity pathways using five example case studies. Each of these genetic toxicology AOPs proposed for further development includes the relevant molecular initiating events, key events, and adverse outcomes (AOs), identification and/or further development of the appropriate assays to link an agent to these events, and discussion regarding the biological plausibility of the proposed AOP. A key difference between these proposed genetic toxicology AOPs versus traditional AOPs is that the AO is a genetic toxicology endpoint of potential significance in risk characterization, in contrast to an adverse state of an organism or a population. The first two detailed case studies describe provisional AOPs for aurora kinase inhibition and tubulin binding, leading to the common AO of aneuploidy. The remaining three case studies highlight provisional AOPs that lead to chromosome breakage or mutation via indirect DNA interaction (inhibition of topoisomerase II, production of cellular reactive oxygen species, and inhibition of DNA synthesis). These case studies serve as starting points for genotoxicity AOPs that could ultimately be published and utilized by the broader toxicology community and illustrate the practical considerations and evidence required to formalize such AOPs so that they may be applied to genetic toxicity evaluation schemes. Environ. Mol. Mutagen. 61:114–134, 2020. © 2019 Wiley Periodicals, Inc. 相似文献
5.
6.
Sebastian Bonner Thomas Matte Mitchell Rubin Joanne K Fagan Jennifer Ahern David Evans 《The Journal of asthma》2006,43(1):31-35
Although studies have documented underuse of controller medications and overuse of short-acting inhaled ss(2)-agonist among children with persistent asthma in disadvantaged communities, the persistence of oral ss(2)-agonist use in pediatric practice has not been studied since inhaled short-acting ss(2)-agonists became widespread. We describe medications used to treat asthma among children 3 to 5 years of age at 10 Head Start and other subsidized preschool centers in East and Central Harlem, New York City. We interviewed 149 parents/guardians of children who were identified as having probable asthma based on physician's diagnosis, persistent symptoms, hospitalization, and medication use. We classified 86 of the 149 children (58%) as having current persistent asthma. Only 15 of them (17%) were reported to have used controller medications at least 5 days/week in the last 4 weeks-only 2 of whom used inhaled corticosteroids. By contrast, 53 children (62%) used oral ss(2)-agonist in the last 4 weeks, often (72%) in conjunction with nebulized or inhaled short-acting ss(2)-agonist. Use of oral ss(2)-agonist was associated with more severe symptoms. This study documents the continued widespread use of oral ss(2)-agonist for treatment of children in a low-income community with high prevalence of asthma. 相似文献
7.
The authors screened for alcoholism 145 consecutive patients who presented with sexual dysfunction or disorders. Using the Michigan Alcoholic Screening Test (MAST), 29% of the patients scored in the probable alcoholic range. Probable alcoholics were more likely to present without a partner and claimed higher sex drive than nonalcoholic patients. Probable alcoholic males reported less joy and vigor than probable alcoholic females, while the reverse held for the nonalcoholic groups. Blind to the MAST results, the staff made six alcohol-related diagnoses and referred one patient for alcohol treatment. The authors discussed the importance of training faculty and resident staff in the relationship of alcohol abuse associated with psychosexual dysfunctions. 相似文献
8.
Scott E Strome Elizabeth Martin Dallas Flies Dianne Khurana Diva Salomao Koji Tamada Andrei I Chapoval Jan L Kasperbauer Kerry D Olsen Lieping Chen 《Otolaryngology--head and neck surgery》2002,126(2):180-187
OBJECTIVES: CD62L was evaluated as a determinant of human pre-effector T cells. STUDY DESIGN AND SETTING: Phenotype and cytokine secretion profiles of CD62L cells were determined based on activation status. RESULTS: CD62L(Low) T cells demonstrated significantly higher secretion of interleukin (IL)-10 and interferon (IFN)-gamma than did CD62L(High) T cells. After activation, the majority of cells expressed high levels of the CD62L surface marker. Postactivation levels of IL-10 production remained elevated or unchanged. In a murine B16 melanoma model, freshly isolated CD62L(Low) tumor draining lymph nodes (TDLN) T cells showed increased secretion of IL-2 and IL-4 but not of IL-10 or IFN-gamma. The surface expression of CD62L and cytokine secretion patterns were maintained after activation with concomitant increases in IL-10. CONCLUSION: Our results provide evidence that CD62L(Low) T cells in TDLNs of progressively growing squamous cell carcinoma of the head and neck differ phenotypically and functionally from those of mouse origin. SIGNIFICANCE: Characterization of this human CD62L(Low) T cell population provides initial insight regarding novel surface markers in TDLN T cells that might correlate with antitumor reactivity. 相似文献
9.
David H. Wilson Catherine R. Chittleborough Kerry Kirke Janet F. Grant Richard E. Ruffin 《Sozial- und Pr?ventivmedizin》2004,13(5):406-412
Objectives: Heavy smokers are a segment of the smoking population who are at increased risk of smoking-related morbidity and least likely to achieve cessation. This study identifies the impact of heavy smoking on quality of life by gender and describes the subpopulation for improved targeting.Methods: South Australian representative population data (n = 3010) was used to compare the health-related quality of life status of male and female heavy smokers as assessed by the SF-36. 相似文献
10.
Changing patterns of hip fracture care before and after implementation of the prospective payment system 总被引:6,自引:0,他引:6
We tested the hypothesis that since the implementation of the prospective payment system (PPS), elderly patients hospitalized for hip fractures receive shorter, less care-intensive hospitalizations and are more frequently institutionalized. In blinded fashion, we reviewed the charts of elderly patients with hip fractures admitted to a municipal hospital from 1981 through 1985. Demographic and clinical characteristics of patients treated before implementation of the PPS were similar to patients treated thereafter. After implementation of the PPS, the mean length of hospitalization fell from 16.6 to 10.3 days, and the mean number of physical therapy sessions received decreased from 9.7 to 4.9. Concomitantly, the proportion of patients discharged to a nursing home increased (21% to 48%), as did the proportion receiving nursing home care at six months after discharge (13% to 39%). This increase in long-term nursing home placement suggests that the quality of care for elderly patients with hip fractures may have deteriorated. 相似文献