全文获取类型
收费全文 | 109580篇 |
免费 | 9493篇 |
国内免费 | 5544篇 |
专业分类
耳鼻咽喉 | 1221篇 |
儿科学 | 1521篇 |
妇产科学 | 1294篇 |
基础医学 | 14479篇 |
口腔科学 | 2294篇 |
临床医学 | 11354篇 |
内科学 | 17162篇 |
皮肤病学 | 2003篇 |
神经病学 | 6566篇 |
特种医学 | 5037篇 |
外国民族医学 | 23篇 |
外科学 | 12056篇 |
综合类 | 14387篇 |
现状与发展 | 28篇 |
一般理论 | 15篇 |
预防医学 | 7191篇 |
眼科学 | 3020篇 |
药学 | 11466篇 |
67篇 | |
中国医学 | 4308篇 |
肿瘤学 | 9125篇 |
出版年
2024年 | 194篇 |
2023年 | 1072篇 |
2022年 | 2688篇 |
2021年 | 3862篇 |
2020年 | 2716篇 |
2019年 | 2636篇 |
2018年 | 3088篇 |
2017年 | 2834篇 |
2016年 | 2977篇 |
2015年 | 4293篇 |
2014年 | 5331篇 |
2013年 | 5509篇 |
2012年 | 7954篇 |
2011年 | 8351篇 |
2010年 | 5488篇 |
2009年 | 4710篇 |
2008年 | 6173篇 |
2007年 | 5991篇 |
2006年 | 5624篇 |
2005年 | 4906篇 |
2004年 | 3852篇 |
2003年 | 3777篇 |
2002年 | 3163篇 |
2001年 | 3929篇 |
2000年 | 3562篇 |
1999年 | 3043篇 |
1998年 | 1455篇 |
1997年 | 1149篇 |
1996年 | 910篇 |
1995年 | 817篇 |
1994年 | 757篇 |
1993年 | 566篇 |
1992年 | 1355篇 |
1991年 | 1217篇 |
1990年 | 1069篇 |
1989年 | 1130篇 |
1988年 | 964篇 |
1987年 | 913篇 |
1986年 | 818篇 |
1985年 | 698篇 |
1984年 | 430篇 |
1983年 | 355篇 |
1982年 | 216篇 |
1981年 | 163篇 |
1980年 | 143篇 |
1979年 | 216篇 |
1978年 | 89篇 |
1973年 | 103篇 |
1972年 | 98篇 |
1971年 | 94篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
为探讨临床中使用钙制剂抢救链霉素过敏休克病人有良好效果的原因,由被动血凝试验、被动皮肤过敏试验和ELISA法证实,Ca~( )可以抑制链霉素抗原-抗体的反应。这种抑制作用是通过Ca~( )链霉素抗原结合,封闭链霉素抗原决定簇来加以实现的。 相似文献
82.
83.
84.
Leonora Q. Schwandt Henri-Jacques Tjong-Ayong Ranny van Weissenbruch Henny C. der Mei Frans W. J. Albers 《European archives of oto-rhino-laryngology》2006,263(6):518-523
Tracheoesophageal voice prostheses need to be replaced due to increased airflow resistance or retrograde leakage of fluid into the trachea as a consequence of biofilm formation. Previous in vitro studies show a change of aerodynamic features of biofilm covered voice prostheses after removal of the prostheses out of the patient. To assess these changes in an in situ situation, aerodynamic characteristics were measured within 45 patients at the beginning and at the end of the wearing process of the Provox 2 voice prosthesis. As a consequence, the influence of biofilm formation on aerodynamic characteristics can be evaluated. In the majority of cases, leakage through the prosthesis was the reason for replacement. No differences were found in the total flow, volume range and intratracheal pressure (ITP) of the voice prostheses measured. The airflow resistance of biofilm covered prostheses was significantly reduced compared to new clean prostheses. However, no correlation was found between the extent of biofilm and the different aerodynamic features measured. Biofilm formation on the Provox 2 is responsible for both reduction in airflow resistance and leakage through the prosthesis by deterioration of the silicone rubber material. 相似文献
85.
86.
Duk Hyun Sung Joon Young Choi Du-Hwan Kim Eun-Sang Kim Young-Ik Son Young-Seok Cho Su Jin Lee Kyung-Han Lee Byung-Tae Kim 《Journal of nuclear medicine》2007,48(11):1790-1795
The purpose of this study was to investigate whether (18)F-FDG PET/CT is useful for localizing dystonic cervical muscles in patients with idiopathic cervical dystonia (ICD) by comparing disease severity before and disease severity after botulinum toxin (BT) injection into hypermetabolic muscles. METHODS: Six patients with ICD underwent (18)F-FDG PET/CT. Dystonic muscles suitable for BT injection therapy were defined as those showing diffusely increased (18)F-FDG uptake. RESULTS: Hypermetabolic cervical muscles were identified in all 6 patients. In 2 patients who underwent PET/CT both in a supine position and in a sitting position during (18)F-FDG uptake, abnormal hypermetabolic muscles were observed by PET/CT only when patients were in the sitting position with their heads and necks in the adopted abnormal involuntary posture. Symptoms were significantly improved in 4 patients who underwent BT injection therapy guided by PET/CT and who were clinically monitored. CONCLUSION: (18)F-FDG PET/CT is potentially useful for identifying dystonic cervical muscles for BT therapy in patients with ICD. 相似文献
87.
1 宋代社会经济、医事制度与历史地理
1.1 宋代的社会经济
宋朝是我国历史上继唐朝之后,社会经济发展、科技文化进步的一个历史时期,后世有"治隆唐宋"之说.公元960年陈桥兵变,赵匡胤(宋太祖)"黄袍加身"以后,遂代周而自立,是为宋朝,史称北宋.当时的社会在经历了五代十国的战乱之后而趋于安定,经济逐渐恢复,科学也日益发达. 相似文献
88.
89.
Kanta Kishi Michiko Muramatsu Denan Jin Keiichi Furubayashi Shinji Takai Hiroshi Tamai Mizuo Miyazaki 《Hypertension research》2007,30(1):77-83
Chymase is known to generate angiotensin II in the vascular wall. In this study we investigated a novel role for chymase other than angiotensin II production in vascular proliferation after balloon injury. Chymase promoted the migration of vascular smooth muscle cells in the matrix-coated invasion chambers and activated promatrix metalloproteinase-2 obtained from the culture medium of vascular smooth muscle cells. Two weeks after balloon injury, significant neointimal formation was found in dog carotid arteries. After injury, active matrix metalloproteinase-2 was increased in parallel with the augmentation of chymase activity that was seen in the proliferating region of the vascular wall. The oral administration of NK3201 (1 mg/kg per day), a chymase inhibitor, prevented neointimal formation and significantly suppressed both active matrix metalloproteinase-2 and chymase activities 2 weeks after injury. These results suggest that chymase inhibitors can prevent the development of intimal hyperplasia via the inhibition of matrix metalloproteinase-2 activation in balloon-injured arteries. 相似文献
90.