全文获取类型
收费全文 | 45775篇 |
免费 | 2996篇 |
国内免费 | 965篇 |
专业分类
耳鼻咽喉 | 359篇 |
儿科学 | 1157篇 |
妇产科学 | 1204篇 |
基础医学 | 5087篇 |
口腔科学 | 791篇 |
临床医学 | 3968篇 |
内科学 | 10801篇 |
皮肤病学 | 705篇 |
神经病学 | 4132篇 |
特种医学 | 1700篇 |
外国民族医学 | 2篇 |
外科学 | 6116篇 |
综合类 | 2141篇 |
现状与发展 | 2篇 |
一般理论 | 1篇 |
预防医学 | 2369篇 |
眼科学 | 647篇 |
药学 | 3922篇 |
8篇 | |
中国医学 | 1013篇 |
肿瘤学 | 3611篇 |
出版年
2024年 | 126篇 |
2023年 | 420篇 |
2022年 | 1066篇 |
2021年 | 1614篇 |
2020年 | 1043篇 |
2019年 | 1121篇 |
2018年 | 1232篇 |
2017年 | 1017篇 |
2016年 | 1066篇 |
2015年 | 1360篇 |
2014年 | 1774篇 |
2013年 | 2192篇 |
2012年 | 2853篇 |
2011年 | 2874篇 |
2010年 | 1740篇 |
2009年 | 1610篇 |
2008年 | 2424篇 |
2007年 | 2481篇 |
2006年 | 2272篇 |
2005年 | 2151篇 |
2004年 | 1955篇 |
2003年 | 1687篇 |
2002年 | 1525篇 |
2001年 | 1412篇 |
2000年 | 1340篇 |
1999年 | 1240篇 |
1998年 | 447篇 |
1997年 | 333篇 |
1996年 | 355篇 |
1995年 | 272篇 |
1994年 | 254篇 |
1993年 | 210篇 |
1992年 | 670篇 |
1991年 | 567篇 |
1990年 | 537篇 |
1989年 | 550篇 |
1988年 | 456篇 |
1987年 | 420篇 |
1986年 | 400篇 |
1985年 | 315篇 |
1984年 | 259篇 |
1983年 | 210篇 |
1982年 | 116篇 |
1979年 | 211篇 |
1978年 | 128篇 |
1977年 | 110篇 |
1974年 | 122篇 |
1973年 | 125篇 |
1972年 | 122篇 |
1971年 | 110篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
C-fos immunoreactivity was used to reveal brain areas in which neurons were influenced by electrical stimulations applied to the dorsal periaqueductal gray. These stimulations were applied in freely moving rats so that the resulting behaviors could be observed. Shortly afterwards, the brains of the rats were processed for C-fos immunoreactivity. In order to determine the specificity of the brain areas thus labeled, control stimulations were applied to the ventral tegmental area of other rats. Immunoreactive cells were found surrounding the tip of the stimulation electrode within a radius of 0.5 mm. This labeled area extended further along the rostro-caudal axis than along the medio-lateral or dorso-ventral axis in the periaqueductal gray. Distally, clusters of labeled cells were found ipsilaterally in the caudal periaqueductal gray extending to the nucleus cuneiformis, and bilaterally in the locus coeruleus and supramamillary decussation. More widespread labeling was found in most hypothalamic subareas and in the lateral habenula. The labeled brain areas following ventral tegmental area stimulations were totally distinct, and comprised the medial forebrain bundle, the nucleus accumbens, the vertical limb of the diagonal band and the medial septum. The pattern of labeling produced by periaqueductal gray stimulations was therefore specific, and provided information about brain structures involved in the motivational and behavioral effects of such stimulations. 相似文献
72.
73.
74.
Davide Pacini Emmanuel Villa Sofia Martin-Suarez Roberto Di Bartolomeo 《European journal of cardio-thoracic surgery》2005,27(4):717-719
Patients who underwent isolated aortic valve replacement could come to attention for new onset aortic disease or progression of borderline alterations not corrected at the first operation, especially in the subset of bicuspid valve disease. We describe our technique in redo operations for aortic root disease, using only a vascular graft and sparing the previously implanted valve prosthesis. In case of normally functioning mechanical prosthesis, we always left the valve in situ and substituted the aortic root with a Dacron conduit, extending the replacement if necessary to the other diseased portions of the thoracic aorta. 相似文献
75.
微创穿刺术治疗基底节区脑出血临床随机对照研究 总被引:50,自引:3,他引:47
目的评价比较微创穿刺血肿粉碎清除术与内科保守治疗两种方法治疗基底节区脑出血(25~40m l)的疗效异同。方法采用多中心、随机对照试验的方法,42个参研医院共随机入选465例基底节区脑出血患者,根据纳入与排除标准共排除88例,其中资料不全者16例;不符合入选标准者72例,分别为Glasgow评分≤8分(64例)、术前出血量>40m l(7例)、从发病到达急诊室时间>72h(1例)。评价治疗14d时两组患者神经功能缺损程度和日常生活活动能力、治疗3个月时的日常生活活动能力以及3个月和住院期间病死率。结果最终符合入组标准的病例数为377例,其中微创治疗组195例,对照组182例。微创治疗组患者于治疗14d时,神经功能改善明显优于对照组(χ2=7.931,P=0.02);治疗3个月时达良好功能状态的患者比例明显多于对照组(35.91%vs21.82%;χ2=8.294P=0.004)。微创治疗组病,残率明显低于对照组(40.88%vs63.03%,χ2=16.948,P<0.01);两组病死率间差异无显著性意义(6.67%vs8.79%)。结论与单纯内科保守治疗相比,应用微创穿刺血肿粉碎清除术治疗基底节区小血肿不增加病死率,并可明显提高脑出血患者的日常生活活动能力,降低病残率。 相似文献
76.
L. Angrisani F. Favretti F. Furbetta L. Busetto S.B. Doldi E. Lattuada M. Paganelli M. Lucchese N. Basso F.D. Capizzi A. Iuppa G. Lesti N. Di Lorenzo C. Giardiello L. Di Cosmo A. Veneziani S. Lacitignola M. Alkilani P. Forestieri M. Toppino A. Gardinazzi F. Puglisi A. Cascardo P. Bernante G. Silecchia B. Marzano A. Adorni V. Borrelli M. Lorenzo 《Surgery for obesity and related diseases》2005,1(3)
77.
Massimo Chello Costanza Goffredo Giuseppe Patti Dario Candura Rosetta Melfi Stefano Mastrobuoni Germano Di Sciascio Elvio Covino 《European journal of cardio-thoracic surgery》2005,28(6):805-810
Objective: Endothelial dysfunction represents a critical early component of organ injury following cardiopulmonary bypass. Recent studies demonstrate that the treatment with atorvastatin is associated with a significant improvement of endothelial function independently of its efficacy on cholesterol levels. Therefore, we investigated the effects of preoperative atorvastatin treatment on endothelium function after coronary surgery. Methods: Forty patients undergoing coronary surgery were randomized to treatment with atorvastatin (20 mg/die; N = 20) or placebo (N = 20) 3 weeks before surgery. Twenty normal patients served as control group. The flow-mediated dilations (FMD) of the brachial artery after both reactive hyperemia (endothelium dependent) and nitroglycerin administration (endothelium independent) were evaluated at baseline, at 48 h, and 5 days postoperatively. Results: At baseline, the endothelium-dependent FMD was significantly attenuated in coronary versus normal patients (normal 10.3 ± 1.8% vs coronary 4.1 ± 1.6%, p < 0.01). At 48 h postoperatively all patients exhibited a reduced FMD compared with baseline values: the endothelium-dependent dilatation showed a drop of 60.1 + 15% in the patients of the placebo group compared with 45.8 + 16.6% (p < 0.05) those in the atorvastatin group. At the univariate analysis, no significant correlation was found between serum levels of either total cholesterol or HDL cholesterol and FMD. The nitroglycerin-induced dilation was not significantly influenced by extracorporeal circulation as well as by atorvastatin treatment. Conclusions: The endothelial dysfunction following cardiopulmonary bypass is improved by the treatment with atorvastatin, by a mechanism unrelated to the drug efficacy of controlling serum cholesterol levels. 相似文献
78.
79.
80.
The role of aminophylline in the re-formation of peritoneal adhesions was considered in 23 rats. Since the adhesions were obtained, the animals were subsequently divided into three groups, the first one containing seven units, the others containing eight animals each. During the four days prior the surgery, allopurinol at the dose of 50 mg/kg/die was added to the regular ground laboratory chow in the animals of the second group; aminophylline at the dose of 40 mg/kg/die was administered four hours and immediately prior the surgery, to the animals of the third group. The adhesions that we observed, were graded and evaluated assigning them a score. At the moment of the lysis of adhesions, we observed the score of 2.71 +/- 1.11 in the first group, 3.12 +/- 1.13 in the second group, and 2.75 +/- 1.03 in the third one. Matching each group one another no statistically significant difference was found. At the end the experiment, we observed a score of 3.71 +/- 0.49 for the adhesions in the first group, 2 +/- 0.75 in the second group, and 3.87 +/- 0.35 in the third one. Matching these scores with those observed at the moment of their lysis, they appeared significantly higher in the animals of the first group (p less than 0.02) and of the third group (p less than 0.05), but they were lower in the second group (p less than 0.05). Such results indicate that the re-formation of peritoneal adhesions following their lysis is constant, that allopurinol decreases the intensity of the process, while aminophylline increases it. 相似文献