全文获取类型
收费全文 | 2043014篇 |
免费 | 147549篇 |
国内免费 | 6094篇 |
专业分类
耳鼻咽喉 | 27253篇 |
儿科学 | 66379篇 |
妇产科学 | 57397篇 |
基础医学 | 296363篇 |
口腔科学 | 56368篇 |
临床医学 | 188865篇 |
内科学 | 397805篇 |
皮肤病学 | 41558篇 |
神经病学 | 167586篇 |
特种医学 | 76955篇 |
外国民族医学 | 669篇 |
外科学 | 297535篇 |
综合类 | 44592篇 |
现状与发展 | 1篇 |
一般理论 | 685篇 |
预防医学 | 165807篇 |
眼科学 | 45769篇 |
药学 | 148864篇 |
6篇 | |
中国医学 | 4525篇 |
肿瘤学 | 111675篇 |
出版年
2019年 | 16350篇 |
2018年 | 22944篇 |
2017年 | 17588篇 |
2016年 | 19075篇 |
2015年 | 21694篇 |
2014年 | 30207篇 |
2013年 | 46817篇 |
2012年 | 63775篇 |
2011年 | 67928篇 |
2010年 | 40016篇 |
2009年 | 37257篇 |
2008年 | 62909篇 |
2007年 | 66610篇 |
2006年 | 66836篇 |
2005年 | 64967篇 |
2004年 | 61923篇 |
2003年 | 59369篇 |
2002年 | 58053篇 |
2001年 | 91020篇 |
2000年 | 93730篇 |
1999年 | 79131篇 |
1998年 | 22443篇 |
1997年 | 20431篇 |
1996年 | 20153篇 |
1995年 | 19035篇 |
1994年 | 17936篇 |
1993年 | 16927篇 |
1992年 | 62917篇 |
1991年 | 61285篇 |
1990年 | 59595篇 |
1989年 | 56900篇 |
1988年 | 52793篇 |
1987年 | 51701篇 |
1986年 | 49342篇 |
1985年 | 47236篇 |
1984年 | 35636篇 |
1983年 | 30312篇 |
1982年 | 18329篇 |
1979年 | 32555篇 |
1978年 | 23075篇 |
1977年 | 19176篇 |
1976年 | 18619篇 |
1975年 | 19538篇 |
1974年 | 23686篇 |
1973年 | 22976篇 |
1972年 | 21469篇 |
1971年 | 19930篇 |
1970年 | 18723篇 |
1969年 | 17294篇 |
1968年 | 16503篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Hideki Kawaguchi Kazuko Masuo Tomohiro Katsuya Ken Sugimoto Hiromi Rakugi Toshio Ogihara Michael L Tuck 《Hypertension research》2006,29(12):951-959
High blood pressure (BP) is a major determinant of cardiovascular events in obesity. The beta2- and beta3-adrenoceptor polymorphisms are associated with obesity and hypertension. In the present study, we examine the relationships of beta2- and beta3-adrenoceptor polymorphisms with further weight gain-induced BP elevation in obese subjects. Changes in BP, body weight, total body fat-mass, waist-to-hip ratio, plasma norepinephrine (NE) and leptin levels, and beta2(Arg16Gly)- and beta3(Trp64Arg)-adrenoceptor polymorphisms were measured periodically over a 5-year period in 55 entry obese (body mass index [BMI]> or =25.0 kg/m(2)) normotensive (BP<140/90 mmHg) men. BP elevation and weight gain were defined as > or =10% increases from entry levels over 5 years in mean BP or BMI. Obese subjects with weight gain, BP elevation or weight gain-induced BP elevation had higher frequencies of the Gly16 allele of Arg16GIy and Arg64 allele of Trp64Arg. Subjects carrying the Gly16 or Arg64 alleles had significantly greater total fat-mass and waist-to-hip ratio at entry and over a 5-year period compared to the subjects who did not carry these polymorphisms. Subjects carrying the Gly16 allele had similar levels of plasma NE, higher levels of plasma leptin and a lower slope of the regression lines between plasma leptin and NE levels. Those carrying the Arg64 allele had higher plasma NE levels at entry and over a 5-year period compared to the subjects without the Arg64 allele, but plasma leptin levels and slopes were similar. The findings demonstrate that the Arg64 allele of the beta3-adrenoceptor polymorphisms relates to weight gain-induced BP elevation accompanying high plasma NE (heightened sympathetic activity) in obese men. The Gly16 allele of the beta2-adrenoceptor polymorphisms links to weight gain-induced BP elevation associated with leptin resistance. beta2- and beta3-adrenoceptor polymorphisms could predict the future BP elevation and further weight gain-induced BP elevation in originally obese subjects. 相似文献
72.
J Phua E S C Koay D Zhang L K Tai X L Boo K C Lim T K Lim 《The European respiratory journal》2006,28(4):695-702
Levels of the soluble form of the triggering receptor expressed on myeloid cells (sTREM)-1 are elevated in severe sepsis. However, it is not known whether sTREM-1 measurements can distinguish milder bacterial infections from noninfectious inflammation. The present authors studied whether serum sTREM-1 levels differ in community-acquired pneumonia, exacerbations of chronic obstructive pulmonary disease (COPD), asthma and controls, and whether sTREM-1 may be used as a surrogate marker for the need for antibiotics. Serum sTREM-1 levels in 150 patients with pneumonia, COPD and asthma exacerbations and 62 healthy controls were measured. Serum sTREM-1 levels were significantly elevated in pneumonia (median 295.2 ng x mL(-1)), COPD (280.3 ng x mL(-1)) and asthma exacerbations (184.0 ng x mL(-1)) compared with controls (83.1 ng x mL(-1)). Levels were higher in pneumonia and Anthonisen type 1 COPD exacerbations than in type 2 and 3 COPD and asthma exacerbations. The area under the receiver operating characteristics curve for sTREM-1 as a surrogate marker for the need for antibiotics was 0.77. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 were elevated predominantly in pneumonia and Anthonisen type 1 COPD exacerbations versus type 2 and 3 chronic obstructive pulmonary disease exacerbations, asthma and controls. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 has moderate but insufficient accuracy as a surrogate marker for the need for antibiotics in lower respiratory tract infections. 相似文献
73.
74.
75.
76.
77.
Patricia A Wilkosz Sachiko Miyahara Oscar L Lopez Steven T Dekosky Robert A Sweet 《The American journal of geriatric psychiatry》2006,14(4):352-360
BACKGROUND: Psychotic symptoms in Alzheimer disease (AD+P) identify a heritable phenotype associated with more rapid cognitive decline. The authors have proposed that AD+P is itself a composite of a misidentification and a paranoid subtype with increased cognitive impairment restricted to the misidentification type. Most prior studies of the clinical correlates of AD+P have been limited, however, by the inclusion of prevalent cases. METHODS: Subjects with possible or probable AD or mild cognitive impairment (MCI) without psychosis at study entry were assessed at the time of initial presentation and then annually. Psychotic symptoms were assessed using the CERAD Behavioral Rating Scale. Survival analyses used Cox proportional hazard models with time-dependent covariates to examine the predictors of psychosis onset. RESULTS: A total of 288 subjects completed at least one follow-up examination. Mean duration of follow-up was 22.1 months. The incidence of psychosis was 0.19 per person-year. Cognitive impairment was associated with onset of psychosis, largely as a result of its association with onset of the misidentification, but not the paranoid, subtype. Including psychotropic medication use in the model revealed an association of antidepressant use with the onset of psychosis. This latter association appeared to arise from an underlying association between depression and the risk of psychosis onset rather than from antidepressant treatment. CONCLUSION: These findings are consistent with the hypothesis that the misidentification and the paranoid subtypes each define a more biologically homogeneous group than AD+P as a whole. Further exploration of the relationship between depressive symptoms and psychosis in patients with AD is warranted. 相似文献
78.
79.
80.