全文获取类型
收费全文 | 9514篇 |
免费 | 39篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 41篇 |
儿科学 | 1075篇 |
妇产科学 | 339篇 |
基础医学 | 753篇 |
口腔科学 | 296篇 |
临床医学 | 365篇 |
内科学 | 2191篇 |
皮肤病学 | 319篇 |
神经病学 | 408篇 |
特种医学 | 264篇 |
外科学 | 2201篇 |
综合类 | 51篇 |
预防医学 | 295篇 |
眼科学 | 265篇 |
药学 | 319篇 |
中国医学 | 53篇 |
肿瘤学 | 331篇 |
出版年
2023年 | 44篇 |
2022年 | 78篇 |
2021年 | 204篇 |
2020年 | 65篇 |
2019年 | 1362篇 |
2018年 | 1095篇 |
2017年 | 581篇 |
2016年 | 32篇 |
2015年 | 33篇 |
2014年 | 92篇 |
2013年 | 84篇 |
2012年 | 31篇 |
2011年 | 41篇 |
2010年 | 36篇 |
2009年 | 41篇 |
2008年 | 26篇 |
2007年 | 34篇 |
2006年 | 33篇 |
2005年 | 29篇 |
2004年 | 28篇 |
2003年 | 19篇 |
2002年 | 24篇 |
2001年 | 23篇 |
2000年 | 20篇 |
1999年 | 22篇 |
1998年 | 14篇 |
1997年 | 18篇 |
1996年 | 7篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1991年 | 7篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1986年 | 4篇 |
1985年 | 475篇 |
1984年 | 653篇 |
1983年 | 357篇 |
1982年 | 540篇 |
1981年 | 469篇 |
1980年 | 384篇 |
1979年 | 430篇 |
1978年 | 341篇 |
1977年 | 356篇 |
1976年 | 422篇 |
1975年 | 358篇 |
1974年 | 312篇 |
1973年 | 308篇 |
1972年 | 4篇 |
排序方式: 共有9566条查询结果,搜索用时 15 毫秒
71.
Cor triatriatum: study of 20 cases. 总被引:7,自引:0,他引:7
Twenty cases of cor triatriatum are reported. The diagnosis was confirmed by necropsy in 16 cases and at the time of operation in 4. The lesion occurred as an isolated anomaly in 7 cases; in 13, other associated cardiac anomalies were present. Three anatomic types of cor triatriatum were identified in the cases studied at necropsy: diaphragmatic (10 cases), hourglass (3) and tubular (3). The diaphragmatic type was also present in all four cases in which the diagnosis was confirmed at operation. Associated anomalies were found in five cases of the diaphragmatic type and in each case of the hourglass of tubular types. In isolated cor triatriatum the clinical findings were characteristic of pulmonary venous and arterial hypertension. In two cases, one with a communication between the right atrium and the accessory left atrial chamber and one with partial anomalous pulmonary venous connection associated with cor triatriatum, the clinical findings suggested a large left to right shunt with pulmonary arterial hypertension. The clinical findings varied in the cases with associated anomalies, and it was difficult to determine the cause of disturbance of the circulation. 相似文献
72.
73.
Plasma cyclic adenosine 3′5′-monophosphate (AMP) levels were measured in 44 patients with acute myocardial infarction, 33 patients with other cardiac and noncardiac diseases and 20 normal volunteers. The normal range of cyclic AMP was 4 to 16 picomoles/ml. The 35 surviving patients with acute myocardial infarction tended to have a slightly increased level of plasma cyclic AMP during the first 24 hours with a subsequent return to normal; the 9 nonsurvivors had abnormally high levels of cyclic AMP. An inverse correlation was found between cyclic AMP levels and stroke work index, and plasma cyclic AMP levels were of equal or better prognostic value than stroke work index. Plasma cyclic AMP levels were in the normal range in patients without acute myocardial infarction. Thus, very high levels of plasma cyclic AMP, found in patients with fatal myocardial infarction, appear to have clinical significance. 相似文献
74.
Of 95 consecutive patients with active variant angina who underwent ergonovine testing in the coronary care unit while off treatment, 24 (25%) developed serious ventricular arrhythmias: ventricular tachycardia in eight, bigeminy in seven, pairs in five, and frequent ventricular extrasystoles in four. Ergonovine-induced arrhythmias were observed more often in patients with anterior than inferior ST segment elevation (p less than 0.05). ST segment elevation was significantly higher (10.3 +/- 8.1 vs 3.1 +/- 2.1 mm) in patients who developed arrhythmias. All ventricular arrhythmias began within 3 minutes after the onset of ST segment elevation. The intravenous administration of nitroglycerin eliminated arrhythmias in 22 of 24 cases; in only two patients did ventricular arrhythmias develop after the administration of nitroglycerin. Serious ventricular arrhythmias were found during spontaneous variant angina attacks in 14 of 24 patients with ergonovine-induced arrhythmias compared to 16 of 71 patients without ergonovine-induced arrhythmias (p less than 0.001). We conclude that arrhythmias during ergonovine testing are most often caused by ischemia and not reperfusion. Patients with arrhythmias during ergonovine-induced attacks are more likely to have arrhythmias during spontaneous attacks. 相似文献
75.
This is a serial-section study of the conduction system in a 2-year-old boxer with electrocardiographic evidence of complete A-V block. The following findings were present: a lack of communication between the atria and the A-V node, atrophy of the A-V node, and tenuous connections between the A-V node and the A-V bundle. These were accompanied by acute degenerative changes in the conduction system. These changes are considered to be the result of arteriolosclerotic heart disease. 相似文献
76.
Twenty pathologic specimens of heart, each with a cleft in the anterior leaflet of the mitral valve not associated with septal defects of persistent common atrioventricular canal (isolated cleft of the mitral valve), were studied. In 9 cases, there were either no associated anomalies or ones not of functional significance. In each of the other 11 cases there were other significant associated cardiac anomalies, including ventricular septal defect and d-transposition of the great arteries. Functional consequences of the mitral anomaly were mitral insufficiency, subaortic stenosis, or both. Mitral insufficiency was related principally to the width of the cleft. Subaortic stenosis, when present, was due to the position of insertion of accessory chordae in the ventricular septum in a position under the commissure, between the left and right aortic cusps or under the right aortic cusp. 相似文献
77.
Neisseria subflava is a rare cause of bacterial endocarditis. Only seven cases have been identified in the world literature if strict criteria as to organism classification and of endocarditis are applied to individual case reports. The first reported case in an intravenous drug user is described. In addition, findings on serial two-dimensional and M-mode echocardiography performed during and after the treatment period are presented. This patient's recovery with anti-microbial therapy alone despite evidence of aortic and significant mitral valve involvement is in accord with results of other antibiotic-treated cases. 相似文献
78.
Ronald Rosengart Michael Fishbein George C. Emmanouilides 《The American journal of cardiology》1975,35(1):107-111
Severe pulmonary vascular disease developed 1 year after a Mustard operation in a year old boy with transposition of the great arteries and intact ventricular septum. The possible etiologic factors responsible for the development of pulmonary vascular disease are discussed, and it is suggested that this disturbing late postoperative complication may occur more frequently than is recognized. 相似文献
79.
Peter S. Hesslein Howard P. Gutgesell Paul C. Gillette Dan G. McNamara 《American heart journal》1982,103(3):351-357
To screen for sinoatrial node dysfunction following the Mustard procedure for transposition of the great arteries, we studied the chronotropic response to graded maximal treadmill exercise in 29 patients at mean 6.7 years after operation. Although 93% of patients had normal resting heart rate (HR), 83% demonstrated significant depression of maximum HR and/or recovery HR after termination of exercise. These findings were similarly present among a subset of 13 patients with normal exercise tolerance. Resting and exercise-induced HR in 10 patients receiving chronic digoxin therapy were no different than in the 19 patients without medication. Sixteen patients with abnormal chronotropic responses to exercise had intracardiac electrophysiologic evaluation which confirmed sinoatrial node dysfunction in nine. Abnormal HR responses did not correlate with clinical symptoms, cardiac arrhythmias, or postoperative hemodynamics. Maximal exercise testing may be a sensitive noninvasive method to identify sinoatrial node dysfunction in postoperative children. 相似文献
80.
The ambulatory electrocardiographic recordings of six patients with coronary artery disease who died during monitoring were analyzed. In four patients, sinus rhythm was interrupted by sinoatrial, atrioventricular, nodal, or infra-His conduction abnormalities leading to bradyarrhythmic sudden death. Two patients died of sustained ventricular tachycardia or ventricular fibrillation. These data emphasize that the arrhythmias involved in the sudden death syndrome may be more heterogenous than currently appreciated. 相似文献