全文获取类型
收费全文 | 21659篇 |
免费 | 1406篇 |
国内免费 | 50篇 |
专业分类
耳鼻咽喉 | 236篇 |
儿科学 | 588篇 |
妇产科学 | 485篇 |
基础医学 | 4291篇 |
口腔科学 | 436篇 |
临床医学 | 1828篇 |
内科学 | 4258篇 |
皮肤病学 | 666篇 |
神经病学 | 1960篇 |
特种医学 | 907篇 |
外国民族医学 | 2篇 |
外科学 | 2805篇 |
综合类 | 113篇 |
一般理论 | 14篇 |
预防医学 | 1507篇 |
眼科学 | 354篇 |
药学 | 1311篇 |
中国医学 | 27篇 |
肿瘤学 | 1327篇 |
出版年
2022年 | 219篇 |
2021年 | 396篇 |
2020年 | 260篇 |
2019年 | 339篇 |
2018年 | 367篇 |
2017年 | 384篇 |
2016年 | 454篇 |
2015年 | 470篇 |
2014年 | 597篇 |
2013年 | 826篇 |
2012年 | 1144篇 |
2011年 | 1159篇 |
2010年 | 642篇 |
2009年 | 679篇 |
2008年 | 1013篇 |
2007年 | 1050篇 |
2006年 | 996篇 |
2005年 | 963篇 |
2004年 | 853篇 |
2003年 | 819篇 |
2002年 | 819篇 |
2001年 | 582篇 |
2000年 | 525篇 |
1999年 | 491篇 |
1998年 | 203篇 |
1997年 | 199篇 |
1996年 | 183篇 |
1995年 | 135篇 |
1994年 | 146篇 |
1993年 | 129篇 |
1992年 | 244篇 |
1991年 | 301篇 |
1990年 | 265篇 |
1989年 | 279篇 |
1988年 | 249篇 |
1987年 | 236篇 |
1986年 | 244篇 |
1985年 | 248篇 |
1984年 | 163篇 |
1983年 | 158篇 |
1982年 | 110篇 |
1979年 | 197篇 |
1978年 | 133篇 |
1977年 | 125篇 |
1976年 | 106篇 |
1975年 | 146篇 |
1974年 | 152篇 |
1973年 | 134篇 |
1972年 | 133篇 |
1971年 | 117篇 |
排序方式: 共有10000条查询结果,搜索用时 13 毫秒
61.
62.
63.
Kerstin Fischer Alimou Camara Ccile Troupin Sarah K. Fehling Thomas Strecker Martin H. Groschup Noel Tordo Sandra Diederich 《Transboundary and Emerging Diseases》2020,67(2):724-732
The genus Ebolavirus comprises several virus species with zoonotic potential and varying pathogenicity for humans. Ebolaviruses are considered to circulate in wildlife with occasional spillover events into the human population which then often leads to severe disease outbreaks. Several studies indicate a significant role of bats as reservoir hosts in the ebolavirus ecology. However, pigs from the Philippines have been found to be naturally infected with Reston virus (RESTV), an ebolavirus that is thought to only cause asymptomatic infections in humans. The recent report of ebolavirus‐specific antibodies in pigs from Sierra Leone further supports natural infection of pigs with ebolaviruses. However, susceptibility of pigs to highly pathogenic Ebola virus (EBOV) was only shown under experimental settings and evidence for natural infection of pigs with EBOV is currently lacking. Between October and December 2017, we collected 308 serum samples from pigs in Guinea, West Africa, and tested for the presence of ebolavirus‐specific antibodies with different serological assays. Besides reactivity to EBOV nucleoproteins in ELISA and Western blot for 19 (6.2%) and 13 (4.2%) samples, respectively, four sera recognized Sudan virus (SUDV) NP in Western blot. Furthermore, four samples specifically detected EBOV or SUDV glycoprotein (GP) in an indirect immunofluorescence assay under native conditions. Virus neutralization assay based on EBOV (Mayinga isolate) revealed five weakly neutralizing sera. The finding of (cross‐) reactive and weakly neutralizing antibodies suggests the exposure of pigs from Guinea to ebolaviruses or ebola‐like viruses with their pathogenicity as well as their zoonotic potential remaining unknown. Future studies should investigate whether pigs can act as an amplifying host for ebolaviruses and whether there is a risk for spillover events. 相似文献
64.
65.
66.
Post-operative pediatric rectovaginal fistulas are rare, can be challenging to repair, and often recur. The versatility, ease of accessibility, vascularization, and likeness to native vaginal tissues make autologous buccal mucosal grafts a novel tissue substitute for the repair of a recurrent rectovaginal fistula after the surgical repair of anorectal malformations. 相似文献
67.
Fischer M Kamp J Garcia-Castrillo Riesgo L Robertson-Steel I Overton J Ziemann A Krafft T;EED Group 《Resuscitation》2011,82(3):285-293
Aim
The aim of this prospective study was the comparison of four emergency medical service (EMS) systems—emergency physician (EP) and paramedic (PM) based—and the impact of advanced live support (ALS) on patients status in preclinical care.Methods
The EMS systems of Bonn (GER, EP), Cantabria (ESP, EP), Coventry (UK, PM) and Richmond (US, PM) were analysed in relation to quality of structure, process and performance when first diagnosis on scene was cardiac arrest (OHCA), chest pain or dyspnoea. Data were collected prospectively between 01.01.2001 and 31.12.2004 for at least 12 month.Results
Over all 6277 patients were included in this study. The rate of drug therapy was highest in the EP-based systems Bonn and Cantabria. Pain relief was more effective in Bonn in patients with severe chest pain. In the group of patients with chest pain and tachycardia ≥120 beats/min, the heart rate was reduced most effective by the EP-systems. In patients with dyspnoea and SpO2 < 90% the improvement of oxygen saturation was most effective in Bonn and Richmond. After OHCA significant more patients reached the hospital alive in EMS systems with EPs than in the paramedic staffed (Bonn = 35.6%, Cantabria = 30.1%; Coventry = 11.9%, Richmond = 9.2%). The introduction of a Load Distributing Band chest compression device in Richmond improved admittance rate after OHCA (21.7%) but did not reach the survival rate of the Bonn EMS system.Conclusions
Higher qualification and greater training and experience of ALS unit personnel increased survival after OHCA and improved patient's status with cardiac chest pain and respiratory failure. 相似文献68.
Repression of cytochrome P450 activity in human hepatocytes in vitro by a novel hepatotrophic factor, augmenter of liver regeneration 总被引:6,自引:0,他引:6
69.
Although several commercial devices are available which allow tidal volume and air leak monitoring during continuous positive airway pressure (CPAP) in neonates, little is known about their measurement accuracy and about the influence of air leaks on volume measurement. The aim of this in vitro study was the validation of volume and leak measurement under CPAP using a commercial ventilatory device, taking into consideration the clinical conditions in neonatology. The measurement accuracy of the Leoni ventilator (Heinen & L?wenstein, Germany) was investigated both in a leak-free system and with leaks simulated using calibration syringes (2-10 ml, 20-100 ml) and a mechanical lung model. Open tubes of variable lengths were connected for leak simulation. Leak flow was measured with the flow-through technique. In a leak-free system the mean relative volume error +/-SD was 3.5 +/- 2.6% (2-10 ml) and 5.9 +/- 0.7% (20-60 ml), respectively. The influence of CPAP level, driving flow, respiratory rate and humidification of the breathing gas on the volume error was negligible. However, an increasing F(i)O(2) caused the measured tidal volume to increase by up to 25% (F(i)O(2) = 1.0). The relative error +/- SD of the leak measurements was -0.2 +/- 11.9%. For leaks > 19%, measured tidal volume was underestimated by more than 10%. In conclusion, the present in vitro study showed that the Leoni allowed accurate volume monitoring under CPAP conditions similar to neonates. Air leaks of up to 90% of patient flow were reliably detected. For an F(i)O(2) > 0.4 and for leaks > 19%, a numerical correction of the displayed volume should be performed. 相似文献
70.
Pauls S Fischer AC Brambs HJ Fetscher S Höche W Bommer M 《European journal of radiology》2012,81(5):974-978