全文获取类型
收费全文 | 1753篇 |
免费 | 292篇 |
国内免费 | 39篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 102篇 |
妇产科学 | 19篇 |
基础医学 | 101篇 |
口腔科学 | 34篇 |
临床医学 | 293篇 |
内科学 | 589篇 |
皮肤病学 | 60篇 |
神经病学 | 176篇 |
特种医学 | 279篇 |
外科学 | 188篇 |
综合类 | 31篇 |
预防医学 | 66篇 |
眼科学 | 16篇 |
药学 | 57篇 |
中国医学 | 1篇 |
肿瘤学 | 55篇 |
出版年
2024年 | 9篇 |
2023年 | 52篇 |
2022年 | 13篇 |
2021年 | 29篇 |
2020年 | 90篇 |
2019年 | 14篇 |
2018年 | 89篇 |
2017年 | 69篇 |
2016年 | 68篇 |
2015年 | 62篇 |
2014年 | 94篇 |
2013年 | 110篇 |
2012年 | 45篇 |
2011年 | 36篇 |
2010年 | 80篇 |
2009年 | 109篇 |
2008年 | 42篇 |
2007年 | 46篇 |
2006年 | 43篇 |
2005年 | 28篇 |
2004年 | 15篇 |
2003年 | 17篇 |
2002年 | 15篇 |
2001年 | 32篇 |
2000年 | 14篇 |
1999年 | 25篇 |
1998年 | 80篇 |
1997年 | 96篇 |
1996年 | 78篇 |
1995年 | 68篇 |
1994年 | 50篇 |
1993年 | 52篇 |
1992年 | 31篇 |
1991年 | 16篇 |
1990年 | 25篇 |
1989年 | 54篇 |
1988年 | 43篇 |
1987年 | 27篇 |
1986年 | 22篇 |
1985年 | 23篇 |
1984年 | 18篇 |
1983年 | 11篇 |
1982年 | 14篇 |
1981年 | 15篇 |
1980年 | 15篇 |
1979年 | 9篇 |
1977年 | 9篇 |
1976年 | 11篇 |
1975年 | 8篇 |
1971年 | 8篇 |
排序方式: 共有2084条查询结果,搜索用时 0 毫秒
101.
Sarah Finlayson MBChB DPhil Jasper M. Morrow FRACP Pedro M. Rodriguez Cruz MD MSc Christopher D.J. Sinclair PhD Arne Fischmann PD DrMed John S. Thornton PhD Steve Knight BSc Ray Norbury PhD Mel White BSc Michal Al‐hajjar MD Nicola Carboni MD PhD Sandeep Jayawant MD FRCPCh Stephanie A. Robb MD Tarek A. Yousry DrMed Habil FRCR David Beeson PhD Jacqueline Palace DM 《Muscle & nerve》2016,54(2):211-219
102.
2016 Dietary Salt Fact Sheet and Call to Action: The World Hypertension League,International Society of Hypertension,and the International Council of Cardiovascular Prevention and Rehabilitation 下载免费PDF全文
Norm R. C. Campbell MD FRCPC Daniel T. Lackland DrPH Mark L. Niebylski PhD MBA MS Marcelo Orias MD Kimbree A. Redburn MA Peter M. Nilsson MD PhD Xin‐Hua Zhang MD PhD Louise Burrell MD MBChB MRCP FRACP Masatsugu Horiuchi MD PhD FAHA Neil R. Poulter MBBS MSc FRCP FMed Sci Dorairaj Prabhakaran MD DM MSc FRCP FNASc Agustin J. Ramirez MD PhD Alta E. Schutte PhD MSc Rhian M. Touyz MBBCh PhD FRCP FRSE Ji‐Guang Wang MD PhD Michael A. Weber MD 《Journal of clinical hypertension (Greenwich, Conn.)》2016,18(11):1082-1085
103.
Atrial overdrive pacing during wide QRS tachycardia with RBBB morphology. What is the mechanism? 下载免费PDF全文
104.
Day‐case device implantation—A prospective single‐center experience including patient satisfaction data 下载免费PDF全文
105.
Platelet-derived growth factor (PDGF) is a potent mitogen for many cultured connective tissue cells. It is present in concentrated form within the platelet alpha-granules and is believed to be released during platelet degranulation at sites of vascular injury. We have used a sensitive radioreceptor assay to measure PDGF levels in whole blood serum from normal humans [17.5 +/- 3.1 (SD) ng/mL] and baboons (2.7 +/- 1.2 ng/mL). PDGF was not detected in plasma from either species. In addition, plasma was found to substantially reduce the ability of added purified PDGF to bind to the cell surface PDGF receptor on cultured cells, suggesting that plasma may contain a PDGF-binding protein that would serve to inactivate PDGF released into plasma. Calculations of PDGF concentrations in serum have been corrected for the effects of the binding protein. 125I-PDGF injected intravenously into normal baboons was cleared rapidly from the plasma (t1/2 = two minutes). The rapid clearance of 125I-PDGF did not result from iodination damage, as purified unlabeled PDGF was cleared with comparable kinetics. The rapid clearance of purified and iodinated PDGF did not result from changes in PDGF structure during purification or from removal of PDGF-associated proteins during purification, as PDGF present in freeze-thaw lysates of fresh platelets was cleared equally rapidly. We conclude that release of PDGF at sites of vascular injury would greatly increase the local concentration of PDGF and that PDGF not localized to the site of injury would be rapidly cleared from the circulation. 相似文献
106.
Transfected leukocyte integrin CD11b/CD18 (Mac-1) mediates phorbol ester-activated, homotypic cell:cell adherence in the K562 cell line 总被引:1,自引:0,他引:1
Hickstein DD; Grunvald E; Shumaker G; Baker DM; Back AL; Embree LJ; Yee E; Gollahon KA 《Blood》1993,82(8):2537-2545
The CD11b/CD18 leukocyte integrin molecule mediates diverse neutrophil adherence-related functions, including cell:cell and cell:extracellular matrix attachments. To study the individual role of this leukocyte integrin in cell adherence in hematopoietic cells, we expressed the CD11b/CD18 complex on the surface of K562 cells, a cell line derived from an individual with chronic myelogenous leukemia in blast crisis. We used an amphotrophic retroviral vector designated LCD18SN, harboring the complete coding sequence for the CD18 subunit, to transfer the CD18 cDNA into K562 cells and select stable cell lines. The CD11b subunit in the expression plasmid pREP4 was transfected into these K562/CD18 cells by electroporation and stable cell clones were selected. These K562 cells possessed RNA and intracellular protein for each subunit, and they expressed the CD11b/CD18 heterodimer on the cell surface. When CD11b/CD18 expressing K562 cells were stimulated with phorbol myristate acetate (50 ng/mL) for 24 to 48 hours, these K562 cells formed dense cell:cell aggregates. This homotypic aggregation required both activation of the CD11b/CD18 complex and the induction of the counter- receptor for CD11b/CD18 on the conjugate cell. This cell line will (1) enable the structure-function relationships between cell activation and homotypic adherence to be assessed, (2) provide the opportunity to identify accessory molecules required for activation of the CD11b/CD18 complex, and (3) facilitate the identification of novel ligands for the CD11b/CD18 complex. 相似文献
107.
Morten Wøjdemann M.D. Pernille Traberg Flemming Stadil DM.Sci Berit Sternby Ph.D. Steen Larsen DM.Sci Linda Hilsted DM.Sci Ole Olsen DM.Sci 《The American journal of gastroenterology》1998,93(2):244-248
Objective : Gastric lipase and gastric acid are secreted simultaneously. The aim of this study was to investigate whether the acid interferes with the lipase secretion. The secretion of human gastric lipase was studied during blockade of gastric acid secretion and modified sham feeding to estimate the impact of these conditions on both gastric lipase enzyme activity and immunoreactivity. Methods : Eight healthy volunteers were intubated with a nasogastric tube. We examined gastric aspirates for the amount and activity of lipase secretion during basal conditions, after blockade of acid secretion with a proton pump inhibitor (omeprazole i.v. infusion), and in response to sham feeding (chewing gum) during the blockade. Results : The amount of secreted gastric lipase was unaffected by blockade of acid secretion and increased significantly after sham feeding (169.9 ± 35.7 g/15 min to 348.1 ± 79.2 g/15 min; p < 0.01 ). Likewise, the output of enzyme activity increased after sham feeding (0.63 ± 0.09 kU/15 min to 1.52 ± 0.36 kU/15 min; p < 0.03 ). The concentration of enzyme activity remained unchanged by blockade of acid secretion, whereas the output of enzyme activity was decreased, probably because of reduced volume secretion or denaturation and conformational changes of the enzyme. Plasma concentrations of gastrin increased in response to blockade of acid secretion (basal 9.6 ± 1.4 pmol/L to 13.3 ± 2.9 pmol/L; p < 0.02 ). Conclusions : Gastric acid secretion is not a prerequisite for gastric lipase secretion. Lipase enzyme activity, though, is sensitive to anacidic conditions. 相似文献
108.
109.
110.