全文获取类型
收费全文 | 3308300篇 |
免费 | 255356篇 |
国内免费 | 6606篇 |
专业分类
耳鼻咽喉 | 47197篇 |
儿科学 | 102306篇 |
妇产科学 | 89188篇 |
基础医学 | 475186篇 |
口腔科学 | 94375篇 |
临床医学 | 306577篇 |
内科学 | 638926篇 |
皮肤病学 | 69321篇 |
神经病学 | 273978篇 |
特种医学 | 130406篇 |
外国民族医学 | 1104篇 |
外科学 | 486637篇 |
综合类 | 75257篇 |
现状与发展 | 9篇 |
一般理论 | 1497篇 |
预防医学 | 269472篇 |
眼科学 | 78378篇 |
药学 | 248194篇 |
11篇 | |
中国医学 | 7179篇 |
肿瘤学 | 175064篇 |
出版年
2018年 | 36309篇 |
2017年 | 27814篇 |
2016年 | 31325篇 |
2015年 | 36407篇 |
2014年 | 50856篇 |
2013年 | 75843篇 |
2012年 | 103345篇 |
2011年 | 108714篇 |
2010年 | 63879篇 |
2009年 | 60518篇 |
2008年 | 101061篇 |
2007年 | 107187篇 |
2006年 | 106861篇 |
2005年 | 104274篇 |
2004年 | 99685篇 |
2003年 | 95518篇 |
2002年 | 93488篇 |
2001年 | 144511篇 |
2000年 | 148874篇 |
1999年 | 126211篇 |
1998年 | 37319篇 |
1997年 | 33723篇 |
1996年 | 33726篇 |
1995年 | 32226篇 |
1994年 | 30242篇 |
1993年 | 28247篇 |
1992年 | 101613篇 |
1991年 | 98808篇 |
1990年 | 95490篇 |
1989年 | 92118篇 |
1988年 | 85671篇 |
1987年 | 84161篇 |
1986年 | 80037篇 |
1985年 | 76270篇 |
1984年 | 57971篇 |
1983年 | 50071篇 |
1982年 | 30360篇 |
1981年 | 27203篇 |
1979年 | 54861篇 |
1978年 | 39161篇 |
1977年 | 32997篇 |
1976年 | 30881篇 |
1975年 | 32806篇 |
1974年 | 40254篇 |
1973年 | 38690篇 |
1972年 | 36483篇 |
1971年 | 33818篇 |
1970年 | 31821篇 |
1969年 | 29763篇 |
1968年 | 27319篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
M Vitacca M Paneroni L Bianchi E Clini A Vianello P Ceriana L Barbano B Balbi S Nava 《The European respiratory journal》2006,27(2):343-349
The present study compared four different sites and conditions for the measurement of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) in 38 spontaneous breathing tracheotomised patients. Of the patients, 28 had chronic obstructive pulmonary disease (COPD). The four different conditions were: 1) through a cuff inflated cannula (condition A); 2) through the mouth with a deflated cannula (condition B); 3) through the mouth with a phonetic uncuffed cannula (condition C); and 4) through the mouth after stoma closure (condition D). Five trials in each condition were performed using a standardised method. The measurement of both MIP and MEP differed significantly depending on the condition of measurement. MIP taken in condition A was significantly higher when compared with conditions B, C and D. MEP in condition A was significantly higher when compared with condition B and D. In condition A the highest frequency of the best measurement of MIP and MEP was observed at the fourth and fifth effort, respectively. The same results were obtained after the selection of only COPD patients. In conclusion, respiratory muscle assessment differs significantly depending on measurement condition. Measurement through inflated cannula tracheotomy yields higher values of both maximal inspiratory and maximal expiratory pressure. 相似文献
42.
A I D'hulst K R Bracke T Maes J L De Bleecker R A Pauwels G F Joos G G Brusselle 《The European respiratory journal》2006,28(1):102-112
Chronic obstructive pulmonary disease (COPD) is characterised by a local pulmonary inflammatory response to respiratory pollutants and by systemic inflammation. Tumour necrosis factor (TNF)-alpha has been implicated in systemic effects of COPD and operates by binding the p55 (R1) and p75 (R2) TNF-alpha receptors. To investigate the contribution of each TNF-alpha receptor in the pathogenesis of COPD, the present study examined the effects of chronic air or cigarette smoke (CS) exposure in TNF-alpha R1 knockout (KO) mice, TNF-alpha R2 KO mice and wild type (WT) mice. CS was found to significantly increase the protein levels of soluble TNF-alpha R1 (by four-fold) and TNF-alpha R2 (by 10-fold) in the bronchoalveolar lavage of WT mice. After 3 months, CS induced a prominent pulmonary inflammatory cell influx in WT and TNF-alpha R1 KO mice. In TNF-alpha R2 KO mice, CS-induced pulmonary inflammation was clearly attenuated. After 6 months, no emphysema was observed in CS-exposed TNF-alpha R2 KO mice in contrast to WT and TNF-alpha R1 KO mice. CS-exposed WT and TNF-alpha R1 KO mice failed to gain weight, whereas the body mass of TNF-alpha R2 KO mice was not affected. These current findings suggest that both tumour necrosis factor-alpha receptors contribute to the pathogenesis of chronic obstructive pulmonary disease, but tumour necrosis factor-alpha receptor-2 is the most active receptor in the development of inflammation, emphysema and systemic weight loss in this murine model of chronic obstructive pulmonary disease. 相似文献
43.
44.
45.
S. Spinty H. Rogozinski G. T. Lealman J. E. Wraith 《Journal of inherited metabolic disease》2003,25(8):697-698
Summary: A female patient with isovaleric acidaemia had a successful outcome from pregnancy. 相似文献
46.
47.
48.
49.
50.