全文获取类型
收费全文 | 11614篇 |
免费 | 549篇 |
国内免费 | 79篇 |
专业分类
耳鼻咽喉 | 262篇 |
儿科学 | 523篇 |
妇产科学 | 535篇 |
基础医学 | 953篇 |
口腔科学 | 548篇 |
临床医学 | 1038篇 |
内科学 | 2557篇 |
皮肤病学 | 159篇 |
神经病学 | 631篇 |
特种医学 | 399篇 |
外国民族医学 | 7篇 |
外科学 | 2283篇 |
综合类 | 251篇 |
一般理论 | 2篇 |
预防医学 | 546篇 |
眼科学 | 357篇 |
药学 | 685篇 |
中国医学 | 46篇 |
肿瘤学 | 460篇 |
出版年
2023年 | 105篇 |
2022年 | 203篇 |
2021年 | 320篇 |
2020年 | 228篇 |
2019年 | 304篇 |
2018年 | 351篇 |
2017年 | 267篇 |
2016年 | 312篇 |
2015年 | 362篇 |
2014年 | 441篇 |
2013年 | 598篇 |
2012年 | 836篇 |
2011年 | 785篇 |
2010年 | 485篇 |
2009年 | 431篇 |
2008年 | 762篇 |
2007年 | 842篇 |
2006年 | 834篇 |
2005年 | 764篇 |
2004年 | 595篇 |
2003年 | 532篇 |
2002年 | 419篇 |
2001年 | 205篇 |
2000年 | 186篇 |
1999年 | 173篇 |
1998年 | 72篇 |
1997年 | 56篇 |
1996年 | 52篇 |
1995年 | 33篇 |
1994年 | 32篇 |
1993年 | 30篇 |
1992年 | 48篇 |
1991年 | 60篇 |
1990年 | 54篇 |
1989年 | 39篇 |
1988年 | 42篇 |
1987年 | 48篇 |
1986年 | 31篇 |
1985年 | 23篇 |
1984年 | 21篇 |
1983年 | 22篇 |
1980年 | 13篇 |
1979年 | 13篇 |
1978年 | 14篇 |
1977年 | 19篇 |
1974年 | 15篇 |
1973年 | 19篇 |
1972年 | 17篇 |
1970年 | 19篇 |
1969年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
Lillian L. L. Leong Marian J. Sturm Yahya Ismail Charlene J. Stephens Roger R. Taylor 《Clinical and experimental pharmacology & physiology》1992,19(2):113-118
1. Phospholipase A2 (PLA2) cleaves phospholipids to produce a lyso-phospholipid and free fatty acid and, in view of the biological activity of the products, PLA2 may play a role in many disease states. Lyso-phospholipids and free arachidonic acid increase in ischaemic myocardium, indicating that ischaemia activates the enzyme. 2. Plasma PLA2 activity was measured in patients with acute myocardial infarction, based on the release of labelled arachidonic acid from Escherichia coli cell membrane. Fourteen males (peak serum creatine phosphokinase (CK) above twice upper normal) were studied on day 1 (within 6 h of chest pain onset), days 2-4, and days 6-9. Normal age matched males (n = 13) were also studied. 3. Plasma PLA2 in patients with uncomplicated myocardial infarction (n = 12) was, initially, 1.14 +/- 0.10 (s.e.m.) nmol/min per mL plasma, similar to that in the normal group (1.52 +/- 0.14). On days 2-4, PLA2 activity increased to 1.94 +/- 0.18 (P less than 0.001) and this activity was correlated with the earlier peak CK level (P less than 0.02). On days 6-9, PLA2 activity was 1.49 +/- 0.13 while in two patients who developed complications and underwent open-heart surgery between the last two measurements, there were further increases to 4.22 and 4.04 nmol/min per mL. 4. The increase in plasma PLA2 in uncomplicated myocardial infarction is likely to be due to release from the damaged myocardium; whether it contributes to pathophysiology is uncertain. 相似文献
22.
Effects of Hypothermia on Blood Endogenous Endotoxin Levels During Cardiopulmonary Bypass 总被引:1,自引:0,他引:1
Hakan Gerçekoglu M.D. Ozhan Tarim M.D. † Ismail Agar M.D. †† Ahmet Korukçu M.D. Hasan Karabulut M.D. Hüseyin Soydemir M.D. Onur Sokullu M.D. Hüseyin Toklu M.D. Candan B. Johansson Ph.D. † Besim Yigiter M.D. Ercüment Kopman M.D. †† 《Journal of cardiac surgery》1997,12(4):223-227
A bstract Endotoxin activates white blood cells and complement and produces a spectrum of clinical syndromes ranging from fever to septic shock. Although production of endogenous endotoxemia during cardiopulmonary bypass (CPB) has recently been reported, the role of hypothermia on endotoxemia is not clear. In this study, we evaluated the effects of moderate (24–28°C) and mild (32–34°C) hypothermia on blood endotoxin levels. The study population consisted of 20 patients who underwent coronary artery bypass grafting (CABG) with CPB. Moderate systemic hypothermia was applied during aortic cross-clamping in ten patients (group 1) and mild hypothermia in the remaining ten patients (group 2). The mean rectal temperatures were 26.8 ± 1.2°C in group 1 and 33.8 ± 0.8°C in group 2. The blood samples for endotoxin level measurements were obtained before CPB, during aortic cross-clamping, immediately after the release of the cross-clamp, 20 minutes after the release of the cross-clamp, after CPB, and 2 hours postoperatively. There were no endotoxins in any of the samples before CPB, but it was detected after CPB in both groups. The endotoxin levels were significantly higher in group 1 than in group 2. The present study suggests that when hypothermia is the technique of choice, the deleterious effects of endotoxemia on patients with comorbidity must be considered. 相似文献
23.
An entomological survey was carried out during 1986 in ten provinces of Syria representative of the main natural areas of this country. 932 sandflies were caught with aspirators in domestic resting sites. Captures are analysed for each species. 相似文献
24.
R I Rückert M Pirlich P Rogalla M Ismail J M Müller 《European journal of vascular and endovascular surgery》2007,33(3):302-305
PURPOSE: To report the first successful endovascular repair of a non-aneurysmal aortic rupture due to periaortic tumour regression. CASE REPORT: A 58-year-old man developed spontaneous infrarenal aortic rupture following chemotherapy which led to regression of a periaortic mesothelioma that had been diagnosed during explorative laparotomy 11 months earlier. Stent-graft placement was performed with intentional conversion of a bifurcated (Zenith, COOK) into an aorto-uni-iliac system. No complications were encountered during a 40 months follow-up. CONCLUSION: Endovascular repair should be considered as a treatment option in non-aneurysmal aortic rupture. 相似文献
25.
26.
27.
Effect of adding aminophylline infusion to nebulised salbutamol in severe acute asthma. 总被引:3,自引:2,他引:1
下载免费PDF全文
![点击此处可从《Thorax》网站下载免费的PDF全文](/ch/ext_images/free.gif)
BACKGROUND--The benefit of adding theophylline to beta 2 agonists in acute asthmatic attacks has been debated frequently. METHODS--In an open randomised study 25 patients with severe acute asthma who presented to the emergency department were treated with either a combined nebulised salbutamol (5 mg/dose) and aminophylline infusion (0.6-0.9 mg/kg/hour), or nebulised salbutamol alone. RESULTS--The responses to treatment as measured by peak expiratory flow (PEF) and the time taken to achieve maximum PEF were similar in both groups. Side effects were observed more commonly in patients receiving the combined treatment. CONCLUSIONS--Nebulised salbutamol is equally efficacious in acute asthma when given alone or in combination with aminophylline. 相似文献
28.
Arinsoy T; Yilmaz M; Ataoglu O; Bali M; Sindel S 《Nephrology, dialysis, transplantation》1997,12(12):2713-2716
29.
30.
Intravenous amiodarone for short-term treatment of refractory ventricular tachycardia or fibrillation 总被引:8,自引:0,他引:8
P C Nalos Y Ismail J M Pappas W Nyitray T A DonMichael 《American heart journal》1991,122(6):1629-1632
Intravenous amiodarone was administered to 22 patients with recurrent ventricular tachycardia failing an average of 3.0 prior antiarrhythmic agents after a mean of 14.6 cardioversions per patient. Patients received a mean bolus of 239 mg amiodarone, and a constant infusion of 0.5 to 1.0 mg/ml was administered over a mean of 50.7 hours. Hypotension requiring pressor agents was seen in nine patients and temporary pacing was needed in five patients. In the hospital, arrhythmic deaths occurred in two (9%) patients and nonarrhythmic deaths occurred in six (27%) patients. There were three late sudden deaths and three additional patients with appropriate automatic defibrillator discharges in follow-up. Intravenous amiodarone is very effective in preventing arrhythmic deaths in patients with refractory ventricular tachycardia and fibrillation. 相似文献