全文获取类型
收费全文 | 4745篇 |
免费 | 308篇 |
国内免费 | 35篇 |
专业分类
耳鼻咽喉 | 68篇 |
儿科学 | 237篇 |
妇产科学 | 58篇 |
基础医学 | 561篇 |
口腔科学 | 160篇 |
临床医学 | 466篇 |
内科学 | 979篇 |
皮肤病学 | 135篇 |
神经病学 | 178篇 |
特种医学 | 252篇 |
外科学 | 635篇 |
综合类 | 170篇 |
一般理论 | 1篇 |
预防医学 | 167篇 |
眼科学 | 332篇 |
药学 | 323篇 |
1篇 | |
中国医学 | 37篇 |
肿瘤学 | 328篇 |
出版年
2023年 | 30篇 |
2022年 | 75篇 |
2021年 | 131篇 |
2020年 | 84篇 |
2019年 | 90篇 |
2018年 | 145篇 |
2017年 | 95篇 |
2016年 | 133篇 |
2015年 | 128篇 |
2014年 | 200篇 |
2013年 | 206篇 |
2012年 | 367篇 |
2011年 | 381篇 |
2010年 | 196篇 |
2009年 | 169篇 |
2008年 | 300篇 |
2007年 | 318篇 |
2006年 | 256篇 |
2005年 | 267篇 |
2004年 | 229篇 |
2003年 | 194篇 |
2002年 | 157篇 |
2001年 | 98篇 |
2000年 | 107篇 |
1999年 | 97篇 |
1998年 | 30篇 |
1997年 | 25篇 |
1996年 | 30篇 |
1995年 | 23篇 |
1994年 | 23篇 |
1993年 | 15篇 |
1992年 | 41篇 |
1991年 | 47篇 |
1990年 | 40篇 |
1989年 | 33篇 |
1988年 | 36篇 |
1987年 | 46篇 |
1986年 | 18篇 |
1985年 | 32篇 |
1984年 | 23篇 |
1983年 | 14篇 |
1980年 | 9篇 |
1979年 | 15篇 |
1978年 | 11篇 |
1976年 | 8篇 |
1975年 | 12篇 |
1974年 | 11篇 |
1972年 | 9篇 |
1971年 | 13篇 |
1966年 | 9篇 |
排序方式: 共有5088条查询结果,搜索用时 296 毫秒
1.
2.
3.
4.
Marie Warrer Petersen Tine Sylvest Meyhoff Marie Helleberg Maj-Brit Nørregaard Kjær Anders Granholm Carl Johan Steensen Hjortsø Thomas Steen Jensen Morten Hylander Møller Peter Buhl Hjortrup Mik Wetterslev Gitte Kingo Vesterlund Lene Russell Vibeke Lind Jørgensen Klaus Tjelle Thomas Benfield Charlotte Suppli Ulrik Anne Sofie Andreasen Thomas Mohr Morten H. Bestle Lone Musaeus Poulsen Mette Friberg Hitz Thomas Hildebrandt Lene Surland Knudsen Anders Møller Christoffer Grant Sølling Anne Craveiro Brøchner Bodil Steen Rasmussen Henrik Nielsen Steffen Christensen Thomas Strøm Maria Cronhjort Rebecka Rubenson Wahlin Stephan Jakob Luca Cioccari Balasubramanian Venkatesh Naomi Hammond Vivekanand Jha Sheila Nainan Myatra Christian Gluud Theis Lange Anders Perner 《Acta anaesthesiologica Scandinavica》2020,64(9):1365-1375
Introduction
Severe acute respiratory syndrome coronavirus-2 has caused a pandemic of coronavirus disease (COVID-19) with many patients developing hypoxic respiratory failure. Corticosteroids reduce the time on mechanical ventilation, length of stay in the intensive care unit and potentially also mortality in similar patient populations. However, corticosteroids have undesirable effects, including longer time to viral clearance. Clinical equipoise on the use of corticosteroids for COVID-19 exists.Methods
The COVID STEROID trial is an international, randomised, stratified, blinded clinical trial. We will allocate 1000 adult patients with COVID-19 receiving ≥10 L/min of oxygen or on mechanical ventilation to intravenous hydrocortisone 200 mg daily vs placebo (0.9% saline) for 7 days. The primary outcome is days alive without life support (ie mechanical ventilation, circulatory support, and renal replacement therapy) at day 28. Secondary outcomes are serious adverse reactions at day 14; days alive without life support at day 90; days alive and out of hospital at day 90; all-cause mortality at day 28, day 90, and 1 year; and health-related quality of life at 1 year. We will conduct the statistical analyses according to this protocol, including interim analyses for every 250 patients followed for 28 days. The primary outcome will be compared using the Kryger Jensen and Lange test in the intention to treat population and reported as differences in means and medians with 95% confidence intervals.Discussion
The COVID STEROID trial will provide important evidence to guide the use of corticosteroids in COVID-19 and severe hypoxia.5.
Drishty Satpati Ketaki Bapat Archana Mukherjee Sharmila Banerjee Kanchan Kothari Meera Venkatesh 《Applied radiation and isotopes》2006,64(8):888-892
Studies on the development of imaging agents for targeting neuroreceptors is an area of considerable interest owing to the limited availability of specific as well as selective radiolabeled agents. Therefore, with an aim of developing a receptor-specific agent, iminodiacetic acid (IDA) derivative of 5-hydroxy tryptamine viz., HTIDA has been synthesized. HTIDA could be radiolabeled with the synthon [(99m)Tc(CO)(3)(H(2)O)(3)](+) in >98% yield. The biodistribution studies in normal Swiss mice showed that the (99m)Tc(CO)(3)-HTIDA crosses the blood-brain barrier successfully with a brain uptake of 0.5%ID/g at 5min post injection. The other relevant observations from biodistribution studies included no significant uptake in any other organ and fast clearance from blood, lungs and liver. 相似文献
6.
7.
8.
9.
Biochemical mechanisms underlying acrylamide induced neurotoxicity were examined using an in vitro model consisting of sagittal slices of rat brain. Incubation of brain slices under oxygen in artificial cerebrospinal fluid containing acrylamide produced a dose and time dependent inhibition of glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Lysosomal enzymes, acid phosphatase, N-acetyl glucosaminidase and beta-glucuronidase decreased in a similar manner, while no changes were observed in the activity of Na+K+ATPase, cytochrome c oxidase and lactate dehydrogenase. Incubation of slices with two structurally related compounds, acetamide (a non-neurotoxic amide) and methylene bis-acrylamide (a weak neurotoxin), indicated that acrylamide selectively inhibited GAPDH, enolase and N-acetyl glucosaminidase at low concentration; similar doses of acetamide and methylene bis-acrylamide did not have the same effect on brain slices. Incubation with acrylamide depleted glutathione levels in slices, and the addition of glutathione to the incubation medium prevented acrylamide induced inhibition of GAPDH and lysosomal enzymes. Time dependent inhibition of lysosomal enzymes was also observed in vivo, in the brain and sciatic nerve of rats following a single dose of acrylamide. These results demonstrate that both in vitro and in vivo, lysosomal enzymes are also inhibited following acrylamide exposure. The rat brain slice model exhibits both selectivity and sensitivity towards neurotoxicants and hence, may prove to be an useful in vitro model for the mechanistic evaluation of neurotoxicity. 相似文献
10.