全文获取类型
收费全文 | 2436528篇 |
免费 | 186140篇 |
国内免费 | 7012篇 |
专业分类
耳鼻咽喉 | 31971篇 |
儿科学 | 80309篇 |
妇产科学 | 68611篇 |
基础医学 | 351588篇 |
口腔科学 | 66559篇 |
临床医学 | 229400篇 |
内科学 | 475181篇 |
皮肤病学 | 52943篇 |
神经病学 | 201675篇 |
特种医学 | 90463篇 |
外国民族医学 | 791篇 |
外科学 | 349929篇 |
综合类 | 56176篇 |
现状与发展 | 4篇 |
一般理论 | 895篇 |
预防医学 | 202137篇 |
眼科学 | 54611篇 |
药学 | 175773篇 |
7篇 | |
中国医学 | 5680篇 |
肿瘤学 | 134977篇 |
出版年
2021年 | 19086篇 |
2019年 | 20306篇 |
2018年 | 28491篇 |
2017年 | 21606篇 |
2016年 | 24032篇 |
2015年 | 27112篇 |
2014年 | 38047篇 |
2013年 | 57971篇 |
2012年 | 79029篇 |
2011年 | 83855篇 |
2010年 | 49048篇 |
2009年 | 46165篇 |
2008年 | 77157篇 |
2007年 | 81606篇 |
2006年 | 82258篇 |
2005年 | 79616篇 |
2004年 | 75861篇 |
2003年 | 72424篇 |
2002年 | 69948篇 |
2001年 | 114000篇 |
2000年 | 117147篇 |
1999年 | 97744篇 |
1998年 | 27983篇 |
1997年 | 25409篇 |
1996年 | 25237篇 |
1995年 | 24075篇 |
1994年 | 22164篇 |
1993年 | 20808篇 |
1992年 | 75800篇 |
1991年 | 73439篇 |
1990年 | 71162篇 |
1989年 | 67595篇 |
1988年 | 62526篇 |
1987年 | 60887篇 |
1986年 | 57442篇 |
1985年 | 54793篇 |
1984年 | 41593篇 |
1983年 | 35381篇 |
1982年 | 21546篇 |
1981年 | 19074篇 |
1979年 | 37489篇 |
1978年 | 26544篇 |
1977年 | 22015篇 |
1976年 | 21159篇 |
1975年 | 21683篇 |
1974年 | 26381篇 |
1973年 | 25747篇 |
1972年 | 23802篇 |
1971年 | 21968篇 |
1970年 | 20691篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
J L Dubois-Randé D Loisance A M Duval-Moulin P Deleuze D Lellouche O Tavolaro L Hittinger C Benvenuti P Merlet D Brun 《Archives des maladies du coeur et des vaisseaux》1989,82(8):1433-1438
Enoximone is a positive inotropic agent belonging to the group of phosphodiesterase F-III inhibitors. The drug was tested in 34 patients uncontrolled by sympathomimetic drugs and referred to our department for urgent heart transplantation or circulatory assistance. After insertion of a Swan-Ganzgatheter and a radial artery catheter for haemodynamic monitoring, enoximone was administered as a 15-minute intravenous bolus injection of 1 to 2.5 mg/kf every 8 hours, in addition to sympathomimetic agents. Clinical and haemodynamic improvement was observed after thirty minutes in 30 patients. The cardiac index rose from 1.82 to 2.67 l/min/m2 and the pulmonary wedge pressure fell from 30.8 to 18.9 mmHg. Systemic arterial resistance decreased from 2170 to 1520 dyn. s. cm-5, and pulmonary resistance from 5.5 to 4.6 Wood units (p less than 0.01 for all values). Four patients had no haemodynamic improvement and were put on circulatory assistance, using a Jarvik 7 total artificial heart in 3 of them and heterotopic circulatory assistance in one. After clinical investigation for contra-indication to heart transplantation, and as their improved haemodynamic status permitted, 12 of the 30 patients were considered suitable (group B) for heart transplantation. Transplantation was performed within a week of admission in 11 patients without any need for mechanical assistance. One of the group B patients who required implantation of a Jarvik 7 artificial heart died after 12 hours of assistance. Eighteen patients were considered unsuitable for transplantation (group A) and treated medically.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
993.
In 422 patients admitted from the emergency department (ED) for suspected acute myocardial infarction, the hypothesis that chest pain that persists on arrival in the ED or recurs during the initial ED evaluation is a useful predictor of acute myocardial infarction (AMI) and complications of coronary ischemia was tested. Compared with patients whose chest pain spontaneously ceased before arrival in the ED, patients whose chest pain persisted or recurred during the initial ED evaluation had a 2.3 times greater risk of interventions (P less than .001), a 1.7 times greater risk of complications (P = .045), a 3.8 times greater risk of life-threatening complications (P = .04), and a 2.4 times greater risk of AMI (P = .005). A third group of patients with suspected AMI never experienced chest pain. This group of patients who never experienced chest pain had a three times higher risk of death (P = .02) compared with patients whose chest pain persisted or recurred in the ED, and a 2.1 times greater risk of intervention (P = .01), a 5.2 times greater risk of life-threatening complication (P = .015), and a 7.9 times greater risk of death (P = .025) compared with patients whose chest pain resolved before arrival in the ED. It was concluded that patients with chest pain that resolves spontaneously before arrival to the ED have a better in-hospital prognosis than any other group. 相似文献
994.
995.
996.
J Prinseau A Baglin J Benoit J M Leparc C Got M F Louis B Attar D Fritel 《Annales de médecine interne》1989,140(2):94-98
The incidence of beta-2 microglobulin amyloidosis was assessed in two populations of chronic hemodialysis patients. Out of 34 patients who underwent biopsy during orthopedic surgery (33 cases) or autopsy (1 case), 26 had amyloid deposits which fixed anti-beta microglobulin serum. Out of 55 unselected patients treated for over months at the dialysis centre, 14 (25%) had clinical symptoms suggesting amyloidosis and out of 43 patients who had a systematic radiological skeletal survey, 23 (53%) had bone deposits. The plasma beta microglobulin concentrations (about 20 times the normal value) we not significantly different whether or not the patients had histological proven amyloidosis, clinically or radiologically probable amyloidosis, no detectable amyloidosis. However, the duration of hemodialysis was longer in those with proven or highly probable amyloidosis. The finding illustrate the indirect role of elevation of beta-2 microglobulin in the genesis of this pathology and also the necessity of lowering its concentration in order to avoid the long term complications of osteoarticular deposits, the functional consequences of which may be very serious. 相似文献
997.
Adverse hemodynamic and clinical effects of encainide in severe chronic heart failure 总被引:1,自引:0,他引:1
STUDY OBJECTIVE: To evaluate the hemodynamic effects of the antiarrhythmic drug, encainide, in patients with severe chronic heart failure. DESIGN: Unblinded, before-after study. SETTING: Referral center for patients with heart failure. PATIENTS: Thirty patients with severe chronic heart failure and a left ventricular ejection fraction less than 40%. INTERVENTIONS: Invasive hemodynamic measurements were done (using a balloon-tipped thermodilution catheter) before and for 3 hours after a single oral dose of 50 mg of encainide. MEASUREMENTS AND MAIN RESULTS: Ninety to one hundred and twenty minutes after its administration, encainide produced a significant deterioration in cardiac performance, as reflected by a fall in cardiac index from 2.3 to 1.8 L/min.m2 body surface (mean change 0.5 +/- 0.1; P less than 0.001), a fall in stroke work index from 26 to 18 g.m/m2 (mean change 8 +/- 2; P less than 0.001), and an increase in left ventricular filling pressure from 19 to 22 mm Hg (mean change 3 +/- 2; P less than 0.05). These deleterious hemodynamic effects were accompanied by worsening symptoms of heart failure in 8 of the 30 patients. Serum levels of encainide and its metabolites, O-desmethylencainide and 3-methoxy-O-desmethylencainide, were within the therapeutic range in most patients. CONCLUSIONS: Encainide can cause adverse hemodynamic and clinical effects in patients with severe chronic heart failure. 相似文献
998.
A single trypanosome is sufficient to infect a tsetse fly 总被引:2,自引:0,他引:2
999.
1000.