全文获取类型
收费全文 | 651篇 |
免费 | 26篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 26篇 |
妇产科学 | 6篇 |
基础医学 | 60篇 |
口腔科学 | 38篇 |
临床医学 | 48篇 |
内科学 | 190篇 |
皮肤病学 | 13篇 |
神经病学 | 19篇 |
特种医学 | 96篇 |
外科学 | 57篇 |
综合类 | 51篇 |
预防医学 | 27篇 |
眼科学 | 6篇 |
药学 | 41篇 |
肿瘤学 | 19篇 |
出版年
2022年 | 6篇 |
2021年 | 4篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2018年 | 12篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 10篇 |
2014年 | 9篇 |
2013年 | 23篇 |
2012年 | 8篇 |
2011年 | 14篇 |
2010年 | 27篇 |
2009年 | 25篇 |
2008年 | 11篇 |
2007年 | 36篇 |
2006年 | 37篇 |
2005年 | 12篇 |
2004年 | 31篇 |
2003年 | 17篇 |
2002年 | 18篇 |
2001年 | 14篇 |
2000年 | 11篇 |
1999年 | 11篇 |
1998年 | 33篇 |
1997年 | 34篇 |
1996年 | 40篇 |
1995年 | 22篇 |
1994年 | 15篇 |
1993年 | 22篇 |
1992年 | 10篇 |
1991年 | 7篇 |
1990年 | 7篇 |
1989年 | 28篇 |
1988年 | 16篇 |
1987年 | 19篇 |
1986年 | 11篇 |
1985年 | 11篇 |
1984年 | 11篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1981年 | 7篇 |
1980年 | 10篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 5篇 |
1976年 | 5篇 |
1975年 | 5篇 |
1938年 | 1篇 |
1935年 | 1篇 |
排序方式: 共有698条查询结果,搜索用时 15 毫秒
121.
122.
Kumar SR Sathish Venkata Bhaskara Rao Kokati 《Asian Pacific Journal of Tropical Biomedicine》2012,2(10):787-792
Objective
To investigate the antibacterial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus (MDRSA).Methods
Fifty one actinobacterial strains were isolated from salt pans soil, costal area in Kothapattanam, Ongole, Andhra Pradesh. Primary screening was done using cross-streak method against MDRSA. The bioactive compounds are extracted from efficient actinobacteria using solvent extraction. The antimicrobial activity of crude and solvent extracts was performed using Kirby-Bauer method. MIC for ethyl acetate extract was determined by modified agar well diffusion method. The potent actinobacteria are identified using Nonomura key, Shirling and Gottlieb 1966 with Bergey''s manual of determinative bacteriology.Results
Among the fifty one isolates screened for antibacterial activity, SRB25 were found efficient against MDRSA. The ethyl acetate extracts showed high inhibition against test organism. MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000 µg/mL. The isolated actinobacteria are identified as Streptomyces sp with the help of Nonomura key.Conclusions
The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms. 相似文献123.
124.
PURPOSE: This article reports on a within-family study to identify factors that lead mothers to expect that a particular child will serve in the role of primary caregiver. DESIGN AND METHODS: Data for this study were collected by in-person interviews with a representative sample of 566 mothers between the ages of 65 and 75 years residing in the greater Boston area, who provided detailed information regarding all of their adult children. Both multivariate and qualitative data analyses were conducted. RESULTS: Emotional closeness and similarity of gender and attitudes were strongly associated with which children mothers identified as probable caregivers. Findings regarding exchange were mixed. Mothers were more likely to name adult children who had provided them with support; however, mothers' past provision of assistance to children was unrelated to expectations regarding care. No aspects of children's availability besides proximity and employment of adult children affected mothers' expectations. In selecting a primary caregiver, mothers emphasized expressive characteristics of intergenerational relationships, rather than instrumental and contextual factors associated with children's availability. IMPLICATIONS: The findings indicated a discrepancy between maternal preference for care and actual patterns of support from adult children. Practitioners who work with older adults and their families should incorporate parents' views of the "likely" caregiver into family counseling protocols. Family counseling in both the precaregiving and actual care provision stages may be useful to clarify expected roles for children. 相似文献
125.
126.
127.
Objective: Young people with asthma often lack engagement in self-management. Smartphone apps offer an attractive, immediate method for obtaining asthma information and self-management support. In this research we developed an evidence-based asthma app tailored to young peoples needs, created using a participatory design approach to optimize user engagement. This paper describes the participatory design process. Methods: This multi-phased research included concept generation and ideation of app design by young people with asthma, and development of asthma information by the research team. Clinical review was sought regarding safety and accuracy of app content. Participants suggestions for improvement and any problems with the app were logged throughout. Our young co-designers were invited back to test a high fidelity prototype app using a “think aloud” process and completed a usability questionnaire. Results: Twenty asthma patients aged 15-24 years contributed to the initial app design. Three respiratory specialists and two pharmacists suggested minor corrections to clinical terminology in the app which were all incorporated. Nine co-designers acted as expert reviewers of the prototype app, of whom eight completed a usability questionnaire. Median usability scores (maximum score 6) indicated high satisfaction with app content, usefulness and ease of use [median item score 5.3 (range 4.7-6.0)]. All feedback was incorporated to create an updated prototype app. Conclusions: A clinically sound asthma app has been developed which is considered highly acceptable to the young co-designers. A six-week test of the engagement, acceptability, and usefulness of the app in young people not involved in the participatory design will follow. 相似文献
128.
Shungu DC Weiduschat N Murrough JW Mao X Pillemer S Dyke JP Medow MS Natelson BH Stewart JM Mathew SJ 《NMR in biomedicine》2012,25(9):1073-1087
Chronic fatigue syndrome (CFS) is a complex illness, which is often misdiagnosed as a psychiatric illness. In two previous reports, using (1)H MRSI, we found significantly higher levels of ventricular cerebrospinal fluid (CSF) lactate in patients with CFS relative to those with generalized anxiety disorder and healthy volunteers (HV), but not relative to those with major depressive disorder (MDD). In this third independent cross-sectional neuroimaging study, we investigated a pathophysiological model which postulated that elevations of CSF lactate in patients with CFS might be caused by increased oxidative stress, cerebral hypoperfusion and/or secondary mitochondrial dysfunction. Fifteen patients with CFS, 15 with MDD and 13 HVs were studied using the following modalities: (i) (1)H MRSI to measure CSF lactate; (ii) single-voxel (1)H MRS to measure levels of cortical glutathione (GSH) as a marker of antioxidant capacity; (iii) arterial spin labeling (ASL) MRI to measure regional cerebral blood flow (rCBF); and (iv) (31)P MRSI to measure brain high-energy phosphates as objective indices of mitochondrial dysfunction. We found elevated ventricular lactate and decreased GSH in patients with CFS and MDD relative to HVs. GSH did not differ significantly between the two patient groups. In addition, we found lower rCBF in the left anterior cingulate cortex and the right lingual gyrus in patients with CFS relative to HVs, but rCBF did not differ between those with CFS and MDD. We found no differences between the three groups in terms of any high-energy phosphate metabolites. In exploratory correlation analyses, we found that levels of ventricular lactate and cortical GSH were inversely correlated, and significantly associated with several key indices of physical health and disability. Collectively, the results of this third independent study support a pathophysiological model of CFS in which increased oxidative stress may play a key role in CFS etiopathophysiology. 相似文献
129.
130.
K Karthik SR Sundararajan J Dheenadhayalan S Rajasekaran 《Indian Journal of Orthopaedics》2011,45(1):33-38