全文获取类型
收费全文 | 2374569篇 |
免费 | 195328篇 |
国内免费 | 4209篇 |
专业分类
耳鼻咽喉 | 34267篇 |
儿科学 | 72752篇 |
妇产科学 | 62928篇 |
基础医学 | 334880篇 |
口腔科学 | 67524篇 |
临床医学 | 215520篇 |
内科学 | 468736篇 |
皮肤病学 | 47932篇 |
神经病学 | 200779篇 |
特种医学 | 95956篇 |
外国民族医学 | 886篇 |
外科学 | 360401篇 |
综合类 | 56222篇 |
现状与发展 | 1篇 |
一般理论 | 977篇 |
预防医学 | 190603篇 |
眼科学 | 55464篇 |
药学 | 177524篇 |
4篇 | |
中国医学 | 4368篇 |
肿瘤学 | 126382篇 |
出版年
2018年 | 24207篇 |
2016年 | 20577篇 |
2015年 | 23278篇 |
2014年 | 33533篇 |
2013年 | 50828篇 |
2012年 | 68733篇 |
2011年 | 72271篇 |
2010年 | 42469篇 |
2009年 | 40860篇 |
2008年 | 68754篇 |
2007年 | 73097篇 |
2006年 | 73995篇 |
2005年 | 72034篇 |
2004年 | 69332篇 |
2003年 | 67010篇 |
2002年 | 66258篇 |
2001年 | 112449篇 |
2000年 | 116525篇 |
1999年 | 98332篇 |
1998年 | 27857篇 |
1997年 | 25522篇 |
1996年 | 25447篇 |
1995年 | 24609篇 |
1994年 | 23159篇 |
1993年 | 21552篇 |
1992年 | 79386篇 |
1991年 | 76393篇 |
1990年 | 73575篇 |
1989年 | 70841篇 |
1988年 | 65846篇 |
1987年 | 64800篇 |
1986年 | 61334篇 |
1985年 | 58399篇 |
1984年 | 44222篇 |
1983年 | 37657篇 |
1982年 | 22886篇 |
1981年 | 20332篇 |
1980年 | 19034篇 |
1979年 | 41299篇 |
1978年 | 28985篇 |
1977年 | 24346篇 |
1976年 | 22832篇 |
1975年 | 23964篇 |
1974年 | 29638篇 |
1973年 | 28042篇 |
1972年 | 26226篇 |
1971年 | 24151篇 |
1970年 | 22752篇 |
1969年 | 21087篇 |
1968年 | 19135篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Peter G. Danias Thomas H. Hauser George Katsimaglis Rene M. Botnar Warren J. Manning 《Herz》2003,15(4):90-98
Coronary magnetic resonance angiography (CMRA) is a technique in clinical evolution. Current clinical applications include assessment for coronary anomalies, aneurysms, bypass graft patency, and, in experienced centers, the exclusion of proximal and multivessel coronary artery disease (CAD). As local expertise increases and more extensive multicenter data become available, additional applications will be established. CMRA promises to supplement and in some cases obviate the need for X-ray contrast angiography, and to expand our understanding of the pathophysiology of CAD. Zusammenfassung Die Magnetresonanzangiographie der Koronargefäße (CMRA) ist eine sich ständig weiterentwickelnde Technik. Etablierte Anwendungen sind zurzeit die Beurteilung von koronaren Anomalien, Aneurysmen und der Durchgängigkeit von Bypasses. Auch der Ausschluss proximaler Koronarstenosen und einer koronaren Mehrgefäßerkrankung ist in einigen spezialisierten Zentren möglich. Mit zunehmender Erfahrung der jeweiligen Anwender und der Verfügbarkeit von Ergebnissen großer multizentrischer Studien können zukünftig weitere klinische Anwendungen etabliert werden. In der Zukunft könnte die CMRA ergänzende Informationen zur Indikationsstellung einer konventionellen Röntgenangiographie bringen und in einigen Fällen diese Untersuchung sogar ersetzen. Die CMRA wird unseren Einblick in die Pathophysiologie der koronaren Herzerkrankung sicher erweitern. 相似文献
22.
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
23.
24.
25.
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
26.
27.
28.
29.
30.
Effects of poor glucose handling on arterial stiffness and left ventricular mass in normal children.
AIM: Cardiovascular risk factors can be present in children and young adults. We previously found abnormal microvascular function in children who had glucose intolerance and insulin resistance. The aim of the present study was to investigate whether they also have abnormalities in left ventricular mass (LVM) and arterial stiffness. METHODS: We measured heart dimensions and LVM using echocardiography, and arterial stiffness using pulse wave analysis in 23 children with good glucose handling (postfeeding glucose: 3.9 to 5 mmol/L) and 21 with poor glucose handling (7.7 to 11.4 mmol/L). RESULTS: The time to pulse reflection was slightly shorter in the poorer glucose handlers (mean+/-SD: 143+/-10 vs 153+/-20 ms, P=0.04), suggestive of increased arterial stiffness. Also in this group, there were significant relationships between intraventricular septal thickness, blood pressure and body mass index, but not in the normal glucose handlers. CONCLUSIONS: We have found that normal children who are in the lowest quintile of glucose tolerance in comparison with their peers are exhibiting the first signs of arterial stiffening. In addition, we have seen the beginnings of a relationship between blood pressure, body mass index and left ventricular enlargement in this group. While these changes may not yet be clinically significant, their emergence might be further evidence of early predisposition to cardiovascular disease. 相似文献