全文获取类型
收费全文 | 2363308篇 |
免费 | 170264篇 |
国内免费 | 7658篇 |
专业分类
耳鼻咽喉 | 32000篇 |
儿科学 | 77409篇 |
妇产科学 | 66424篇 |
基础医学 | 331970篇 |
口腔科学 | 65930篇 |
临床医学 | 207347篇 |
内科学 | 469499篇 |
皮肤病学 | 53507篇 |
神经病学 | 189383篇 |
特种医学 | 94363篇 |
外国民族医学 | 617篇 |
外科学 | 365169篇 |
综合类 | 52515篇 |
现状与发展 | 3篇 |
一般理论 | 683篇 |
预防医学 | 182935篇 |
眼科学 | 52495篇 |
药学 | 172148篇 |
41篇 | |
中国医学 | 4264篇 |
肿瘤学 | 122528篇 |
出版年
2018年 | 22862篇 |
2016年 | 20747篇 |
2015年 | 23440篇 |
2014年 | 32649篇 |
2013年 | 49355篇 |
2012年 | 63377篇 |
2011年 | 67926篇 |
2010年 | 41613篇 |
2009年 | 40050篇 |
2008年 | 64492篇 |
2007年 | 69468篇 |
2006年 | 70887篇 |
2005年 | 69073篇 |
2004年 | 66280篇 |
2003年 | 64494篇 |
2002年 | 62283篇 |
2001年 | 108037篇 |
2000年 | 111230篇 |
1999年 | 93718篇 |
1998年 | 27843篇 |
1997年 | 24994篇 |
1996年 | 25843篇 |
1995年 | 25336篇 |
1994年 | 23897篇 |
1993年 | 22253篇 |
1992年 | 77399篇 |
1991年 | 75840篇 |
1990年 | 73857篇 |
1989年 | 70816篇 |
1988年 | 66025篇 |
1987年 | 64725篇 |
1986年 | 61568篇 |
1985年 | 59066篇 |
1984年 | 44716篇 |
1983年 | 38236篇 |
1982年 | 23570篇 |
1981年 | 21056篇 |
1980年 | 19749篇 |
1979年 | 41444篇 |
1978年 | 29674篇 |
1977年 | 25293篇 |
1976年 | 23550篇 |
1975年 | 25318篇 |
1974年 | 29826篇 |
1973年 | 28608篇 |
1972年 | 26814篇 |
1971年 | 24848篇 |
1970年 | 22909篇 |
1969年 | 21849篇 |
1968年 | 20527篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
Aaron Yarlas Martha Bayliss Joseph C. Cappelleri Stephen Maher Andrew G. Bushmakin Lea Ann Chen Alireza Manuchehri Paul Healey 《Quality of life research》2018,27(2):273-290
Purpose
To conduct a systematic literature review of the reliability, construct validity, and responsiveness of the SF-36® Health Survey (SF-36) in patients with ulcerative colitis (UC).Methods
We performed a systematic search of electronic medical databases to identify published peer-reviewed studies which reported scores from the eight scales and/or two summary measures of the SF-36 collected from adult patients with UC. Study findings relevant to reliability, construct validity, and responsiveness were reviewed.Results
Data were extracted and summarized from 43 articles meeting inclusion criteria. Convergent validity was supported by findings that 83% (197/236) of correlations between SF-36 scales and measures of disease symptoms, disease activity, and functioning exceeded the prespecified threshold (r ≥ |0.40|). Known-groups validity was supported by findings of clinically meaningful differences in SF-36 scores between subgroups of patients when classified by disease activity (i.e., active versus inactive), symptom status, and comorbidity status. Responsiveness was supported by findings of clinically meaningful changes in SF-36 scores following treatment in non-comparative trials, and by meaningfully larger improvements in SF-36 scores in treatment arms relative to controls in randomized controlled trials. The sole study of SF-36 reliability found evidence supporting internal consistency (Cronbach’s α ≥ 0.70) for all SF-36 scales and test–retest reliability (intraclass correlation coefficient ≥0.70) for six of eight scales.Conclusions
Evidence from this systematic literature review indicates that the SF-36 is reliable, valid, and responsive when used with UC patients, supporting the inclusion of the SF-36 as an endpoint in clinical trials for this patient population.103.
104.
Veterans are at an increased risk of being injured or killed in motor vehicle crashes, potentially due to their proclivity to engage in risky driving behaviors. However, most research in this area has focused on driving behaviors of veterans who have recently returned home after deployment. No research has focused on risky driving behaviors of older veterans (aged 65 or older) and if risky driving behaviors extend beyond the time period immediately following return from deployment. The purpose of this research is to determine if differences exist in risky driving behaviors of veterans and non-veterans aged 65 or older. This study used data from the 2011 National Health and Aging Trend Study (NHATS), a nationally representative, longitudinal survey of community-dwelling, Medicare beneficiaries aged 65 or older. Binary logistic regression analyses were conducted in 2017 to determine if veteran’s status was predictive of specific risky driving behaviors. Veteran’s status was found to be predictive of specific driving behaviors for adults aged 65 and older, with non-veterans significantly more likely than veterans to: not currently drive; avoid driving at night; avoid driving alone; avoid driving on busy roads or highways; and avoid driving in bad weather. The results of this study highlight the need to further understand the effects of veteran’s status on risky driving behaviors among older adults, specifically, whether veteran’s status compounds driving-related risks associated with aging-related physical and mental changes. 相似文献
105.
106.
107.
108.
109.