全文获取类型
收费全文 | 579篇 |
免费 | 38篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 23篇 |
妇产科学 | 7篇 |
基础医学 | 84篇 |
口腔科学 | 11篇 |
临床医学 | 48篇 |
内科学 | 119篇 |
皮肤病学 | 1篇 |
神经病学 | 22篇 |
特种医学 | 95篇 |
外科学 | 61篇 |
综合类 | 15篇 |
预防医学 | 53篇 |
眼科学 | 11篇 |
药学 | 23篇 |
中国医学 | 3篇 |
肿瘤学 | 45篇 |
出版年
2022年 | 12篇 |
2021年 | 8篇 |
2020年 | 6篇 |
2019年 | 7篇 |
2018年 | 15篇 |
2017年 | 18篇 |
2016年 | 16篇 |
2015年 | 13篇 |
2014年 | 24篇 |
2013年 | 27篇 |
2012年 | 38篇 |
2011年 | 39篇 |
2010年 | 15篇 |
2009年 | 33篇 |
2008年 | 19篇 |
2007年 | 20篇 |
2006年 | 20篇 |
2005年 | 23篇 |
2004年 | 19篇 |
2003年 | 18篇 |
2002年 | 19篇 |
2001年 | 26篇 |
2000年 | 10篇 |
1999年 | 13篇 |
1998年 | 10篇 |
1997年 | 12篇 |
1996年 | 4篇 |
1995年 | 8篇 |
1994年 | 7篇 |
1993年 | 3篇 |
1992年 | 7篇 |
1991年 | 9篇 |
1990年 | 3篇 |
1989年 | 10篇 |
1988年 | 7篇 |
1987年 | 3篇 |
1986年 | 6篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1982年 | 3篇 |
1980年 | 7篇 |
1979年 | 7篇 |
1978年 | 5篇 |
1977年 | 4篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1966年 | 3篇 |
1948年 | 4篇 |
1945年 | 2篇 |
1944年 | 2篇 |
排序方式: 共有622条查询结果,搜索用时 15 毫秒
11.
Opinion statement Left ventricular (LV) remodeling refers to alterations in ventricular mass, chamber size, and shape that result from myocardial
injury, pressure, or volume overload. Numerous studies have demonstrated that LV remodeling correlates with the incidence
of heart failure and death, supporting a causative role for remodeling in heart failure progression. Heart failure trials
have shown that neurohormonal antagonists, including angiotensin-converting enzyme (ACE) inhibitors and β-adrenergic receptor
blockers (β blockers), reduce remodeling in parallel with improved clinical outcomes. Existing data favor using angiotensin
II type 1 (AT1) receptor antagonists (or “ARBs”), although their anti-remodeling effects are less well established. Recently,
mineralocorticoid receptor antagonists have gained substantial interest based on favorable clinical trial results, although
data regarding their effects on remodeling are limited. Thus, an optimal medical regimen to prevent or limit LV remodeling
in patients with LV dysfunction should include both an ACE inhibitor and β-adrenergic receptor antagonist, irrespective of
the degree of LV dysfunction and symptom status. For patients intolerant to ACE inhibitors, an AT1 receptor antagonist should
be substituted. An aldosterone antagonist should be administered to patients with severe, New York Heart Association class
III to IV heart failure who have normal or only mildly impaired renal function, or to those patients with depressed LV function
following an acute myocardial infarction. Through the aggressive pharmacologic inhibition of both the renin-angiotensin-aldosterone
and sympathetic nervous systems, progressive LV remodeling can be prevented or hindered, thereby favorably altering the natural
history of the heart failure syndrome. 相似文献
12.
Sudeshna Patra Pallavi Thakur Bhaskar Soman Anand B. Puthirath Pulickel M. Ajayan Santosh Mogurampelly V. Karthik Chethan Tharangattu N. Narayanan 《RSC advances》2019,9(66):38646
Polymer based solid electrolytes (SEs) are envisaged as futuristic components of safer solid state energy devices. But the semi-crystalline nature and slow dynamics of the host polymer matrix are found to hamper the ion transport through the solid polymer network and hence solid state devices are still far beyond the scope of practical application. In this study, we unravel the synergistic roles of Li salt (LiClO4) and two different polymers – polyethylene oxide (PEO) and polydimethyl siloxane (PDMS), in the Li ion transport through their solid blend based electrolyte. A detailed study using dielectric spectroscopy and thermo-mechanical analysis is conducted to understand the tunability of the PEO chain dynamics with LiClO4 and the mechanism of hopping of Li ions by forming ion pairs with oxygen dipoles on the PEO backbone is established. Despite the lack of PDMS''s capability to solvate ions and promote ion transport directly, its proper mixing within the PEO host matrix is demonstrated to enhance ion transport due to the influence of PDMS on the segmental dynamics of PEO. A detailed molecular dynamics study supported by experimental validation suggests that even inert polymers can affect the dynamics of the active host matrix and increase ion transport, leading to next generation high ionic conductivity solid matrices, and opens new avenues in designing polymer based transparent electrolytes.The studies shown here prove that both the Li salt and ‘inert-polymer’ mixing have paramount importance in the tunability of Li ion conductivity in solid electrolytes for batteries. 相似文献
13.
Shawn P. Grogan Peter H. Chung Pranav Soman Peter Chen Martin K. Lotz Shaochen Chen Darryl D. D’Lima 《Acta biomaterialia》2013,9(7):7218-7226
Meniscus degeneration due to age or injury can lead to osteoarthritis. Although promising, current cell-based approaches show limited success. Here we present three-dimensional methacrylated gelatin (GelMA) scaffolds patterned via projection stereolithography to emulate the circumferential alignment of cells in native meniscus tissue. Cultured human avascular zone meniscus cells from normal meniscus were seeded on the scaffolds. Cell viability was monitored, and new tissue formation was assessed by gene expression analysis and histology after 2 weeks in serum-free culture with transforming growth factor β1 (10 ng ml?1). Light, confocal and scanning electron microscopy were used to observe cell–GelMA interactions. Tensile mechanical testing was performed on unseeded, fresh scaffolds and 2-week-old cell-seeded and unseeded scaffolds. 2-week-old cell–GelMA constructs were implanted into surgically created meniscus defects in an explant organ culture model. No cytotoxic effects were observed 3 weeks after implantation, and cells grew and aligned to the patterned GelMA strands. Gene expression profiles and histology indicated promotion of a fibrocartilage-like meniscus phenotype, and scaffold integration with repair tissue was observed in the explant model. We show that micropatterned GelMA scaffolds are non-toxic, produce organized cellular alignment, and promote meniscus-like tissue formation. Prefabrication of GelMA scaffolds with architectures mimicking the meniscus collagen bundle organization shows promise for meniscal repair. Furthermore, the technique presented may be scaled up to repair larger defects. 相似文献
14.
15.
16.
17.
18.
19.
目的 分析延边地区建立肺结核归口转诊模式对肺结核病人的转诊到位率的影响,探讨提高转诊到位率的方法。方法 对全州8个县(市)医院、中医医院、中心卫生院、大型厂矿企事业单位职工医院的执法检查考核资料进行评价。结果 1.建立归口转诊模式前期转诊率为48.3%,转诊到位率为29.0%,后期转诊率为89.0%,转诊到位率为72.4%,有明显提高;2.前期年平均涂阳病人新登记率为13.36/10万,后期为17.86/10万,实施归口转诊模式前期与实施后期的指标有显著性差异(P<0.01)。结论 延边地区实施的肺结核病人归口转诊模式,对提高肺结核病的转诊到位率十分有效,应不断完善并深入推广。 相似文献
20.
Umut Disel Russell Madison Kumar Abhishek Jon H. Chung Sally E. Trabucco Asli O. Matos Garrett M. Frampton Lee A. Albacker Venkataprasanth Reddy Nuri Karadurmus Adam Benson Jennifer Webster Semra Paydas Ruben Cabanillas Chaitali Nangia M.A. Ozturk Sherri Z. Millis Sumanta K. Pal Breelyn Wilky Ethan S. Sokol Laurie M. Gay Salil Soman Shridar Ganesan Katherine Janeway Phil J. Stephens Viola W. Zhu Sai-Hong Ignatius Ou Christine M. Lovly Mrinal Gounder Alexa B. Schrock Jeffrey S. Ross Vincent A. Miller Samuel J. Klempner Siraj M. Ali 《The oncologist》2020,25(1):e39-e47