全文获取类型
收费全文 | 5263篇 |
免费 | 367篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 30篇 |
儿科学 | 90篇 |
妇产科学 | 76篇 |
基础医学 | 783篇 |
口腔科学 | 184篇 |
临床医学 | 415篇 |
内科学 | 1183篇 |
皮肤病学 | 71篇 |
神经病学 | 624篇 |
特种医学 | 149篇 |
外科学 | 953篇 |
综合类 | 35篇 |
一般理论 | 3篇 |
预防医学 | 252篇 |
眼科学 | 88篇 |
药学 | 346篇 |
中国医学 | 4篇 |
肿瘤学 | 368篇 |
出版年
2024年 | 8篇 |
2023年 | 41篇 |
2022年 | 84篇 |
2021年 | 152篇 |
2020年 | 94篇 |
2019年 | 131篇 |
2018年 | 172篇 |
2017年 | 135篇 |
2016年 | 134篇 |
2015年 | 147篇 |
2014年 | 242篇 |
2013年 | 242篇 |
2012年 | 428篇 |
2011年 | 448篇 |
2010年 | 226篇 |
2009年 | 213篇 |
2008年 | 378篇 |
2007年 | 345篇 |
2006年 | 311篇 |
2005年 | 305篇 |
2004年 | 241篇 |
2003年 | 242篇 |
2002年 | 226篇 |
2001年 | 41篇 |
2000年 | 29篇 |
1999年 | 41篇 |
1998年 | 66篇 |
1997年 | 38篇 |
1996年 | 38篇 |
1995年 | 34篇 |
1994年 | 29篇 |
1993年 | 25篇 |
1992年 | 21篇 |
1991年 | 33篇 |
1990年 | 22篇 |
1989年 | 23篇 |
1988年 | 15篇 |
1987年 | 16篇 |
1986年 | 25篇 |
1985年 | 36篇 |
1984年 | 21篇 |
1983年 | 18篇 |
1982年 | 18篇 |
1981年 | 12篇 |
1980年 | 20篇 |
1979年 | 13篇 |
1978年 | 10篇 |
1974年 | 10篇 |
1973年 | 14篇 |
1967年 | 8篇 |
排序方式: 共有5654条查询结果,搜索用时 15 毫秒
111.
Simon Rauch Tomas Dal Cappello Giacomo Strapazzon Martin Palma Francesco Bonsante Elisabeth Gruber Mathias Ströhle Peter Mair Hermann Brugger 《The American journal of emergency medicine》2018,36(10):1749-1753
Objective
We investigated pre-hospital times, clinical characteristics and therapeutic interventions in multisystem trauma patients injured in mountainous areas in comparison to both urban and suburban trauma patient admissions.Methods
Pre-hospital and in-hospital data collected from trauma patients included in the International Alpine Trauma Register (IATR) hosted in Bolzano, Italy (aged 16–80?yr with an ISS?≥?16), were compared with trauma patient data published from those urban and suburban areas included in the Trauma Register DGU® (TR-DGU) of the German Trauma Society.Results
A total of 94 patients from the IATR and 11,020 patients from the TR-DGU met the inclusion criteria. Due to longer treatment-free intervals (mean 59.1 vs. 19.7?min), total out-of-hospital time was reportedly longer in individuals injured in mountainous areas, compared to urban/suburban areas (117.4?±?142.9 vs. 68.7?±?28.6?min, p?=?0.002), despite the more frequent helicopter rescue (93% vs. 40%, p?<?0.001). 57% of IATR patients were hypothermic at hospital arrival, mean ISS was higher (38.5?±?15.8 vs. 28.6?±?12.2, p?<?0.001) and patients with a systolic blood pressure (SBP) ≤90?mm?Hg were more frequent (27% vs. 15%, p?=?0.005), yet less patients had received volume therapy (82% vs. 93%, p?=?0.001). However, overall no difference in hospital mortality was observed (11% vs. 17%, p?=?0.159).Conclusion
Trauma incidents in mountainous areas commonly feature significantly increased out-of-hospital time which is associated with a more severe ISS, higher risk of accidental hypothermia and more frequent hypotension compared to urban/suburban trauma. Nonetheless, the mortality rate of IATR patients is comparable to urban/suburban trauma patients. 相似文献112.
113.
114.
115.
The anatomy of electrochemical flow microreactors is important to safely perform chemical reactions in order to obtain pure and high yielding substances in a controlled and precise way that excludes the use of supporting electrolytes. Flow microreactors are advantageous in handling unstable intermediates compared to batch techniques and have efficient heat/mass transfer. Electrode nature (cathode and anode) and their available exposed surface area to the reaction mixture, parameters of the spacer, flow rate and direction greatly affects the efficiency of the electrochemical reactor. Solid formation during reactions may result in a blockage and consequently decrease the overall yield, thus limiting the use of microreactors in the field of electrosynthesis. This problem could certainly be overcome by application of ultrasound to break the solids for consistent flow. In this review, we discuss in detail the aforementioned issues, the advances in microreactor technology for chemical synthesis, with possible application of sonochemistry to deal with solid formations. Various examples of flow methods for electrosynthesis through microreactors have been explained in this review, which would definitely help to meet future demands for efficient synthesis and production of various pharmaceuticals and fine chemicals.The advances in flow microreactor technology for chemical synthesis, with possible application of sonochemistry to deal with solid formations. 相似文献
116.
Although in many cardiac surgery centers pharmacological strategies based on fibrinolytic inhibitors are used on a routine basis, detailed knowledge of fibrinolysis during various settings of coronary surgery is still limited. Sixty-five patients scheduled for coronary surgery were randomized into 3 groups: group A--conventional coronary artery bypass grafting, group B--off-pump surgery, and group C--coronary artery bypass grafting with modified, rheoparin coated cardiopulmonary bypass with the avoidance of reinfusion of cardiotomy blood into the circuit. The sampling time points for rotation thromboelastographic evaluations were as follows: preoperatively, 15 minutes after sternotomy, on the completion of peripheral bypass anastomoses, at the end of the procedures, and 24 hours after the end of surgery. D-dimer levels were evaluated before surgery, at the end of procedures, and 24 hours after surgery. Thromboelastographic signs of fibrinolysis (evaluated by Lysis Onset Time-intergroup differences at 60 and 150 minutes of assessment: P = 0.003 and P < 0.001, respectively) were clearly detectable during cardiopulmonary bypass in group A, but not at any time in groups B and C. At the other sampling times all thromboelastographic parameters were similar in all groups. In group A, no exceptional bleeding tendency (during 24 hours), as compared to groups B and C (geometric means and 95% confidence intervals: group A: 686.7 [570.8; 826.1] mL, group B: 555.3 [441.3; 698.9] mL, group C: 775.6 [645.1; 932.3] mL, P = 0.157), and no significant correlations between Lysis Onset Time, postoperative blood loss, and D-dimer levels were found. No significant differences in postoperative blood loss related to cardiac surgeons and assistant surgeons were detected. Thromboelastographic signs of increased fibrinolysis were detectable in the important proportion of coronary surgery patients operated on with the use of conventional cardio-pulmonary bypass, but not in off-pump patients and those operated on with the biocompatible surface-modified circuit without reinfusion of cardiotomy suction blood. These signs resolved spontaneously at the end of surgery and were not associated with increased postoperative bleeding. No significant correlation with D-dimer levels was found. 相似文献
117.
Diane Purper-Ouakil Hilario Blasco-Fontecilla Tomas Ros Eric Acquaviva Tobias Banaschewski Sarah Baumeister Elisa Bousquet Aurore Bussalb Marie Delhaye Richard Delorme Renate Drechsler Allison Goujon Alexander Häge Anna Kaiser Louis Mayaud Konstantin Mechler Caroline Menache Olivier Revol Friederike Tagwerker Susanne Walitza Anna Maria Werling Stephanie Bioulac Daniel Brandeis 《Journal of child psychology and psychiatry, and allied disciplines》2022,63(2):187-198
118.
119.
SIR, The aim of this letter is to show our experience in theuse of leflunomide (LFN) and express our opinion about the recommendeddose [1, 2]. As far as we know, no data exist about a possibleassociation between the loading dose and the presence of adverseevents. Any new suggestion about the use of LFN should be appreciated,specially after the safety of this 相似文献
120.
Vokurka J Olejnik J Jedlicka V Vesely M Ciernik J Paseka T 《Hepato-gastroenterology》2008,55(85):1349-1352
BACKGROUND/AIMS: Acute mesenteric ischemia (AMI) is a serious disease in old age with low incidence but with a very high mortality rate (60-70%). The etiology is either primary (embolism or thrombosis of mesenteric arteries or veins, non-occlusive mesenteric ischemia) or secondary (mechanical obstruction such as intestinal volvulus, intussusception, tumor-caused compression). Independent of the origin of the illness, the clinical-pathological picture is the same: intestinal ischemia with subsequent necrosis. The aim of this study was to ascertain which underlying conditions lead to increased probability of development of acute mesenteric ischemia. METHODS: Two hundred and fifteen patients with a primary form of AMI were treated in the years 1991-2007, in the 1st Clinic of Surgery in Brno, Czech Republic and in the Department of General Surgery, Derer's University Hospital in Bratislava, Slovak Republic; the results of the treatment have been statistically evaluated. CONCLUSION: The probability of arterial mesenteric ischemia development rises significantly (p < 0.05) in patients with a history of atrial fibrillation and/or myocardial infarction. This probability is also significantly higher in smokers with symptoms of hypertension and clinical signs of abdominal angina (p < 0.05). 相似文献