全文获取类型
收费全文 | 88193篇 |
免费 | 7507篇 |
国内免费 | 5935篇 |
专业分类
耳鼻咽喉 | 708篇 |
儿科学 | 1013篇 |
妇产科学 | 703篇 |
基础医学 | 8169篇 |
口腔科学 | 1929篇 |
临床医学 | 11568篇 |
内科学 | 10357篇 |
皮肤病学 | 1085篇 |
神经病学 | 3433篇 |
特种医学 | 3521篇 |
外国民族医学 | 39篇 |
外科学 | 9327篇 |
综合类 | 19328篇 |
现状与发展 | 19篇 |
一般理论 | 12篇 |
预防医学 | 7451篇 |
眼科学 | 1769篇 |
药学 | 9401篇 |
98篇 | |
中国医学 | 5700篇 |
肿瘤学 | 6005篇 |
出版年
2024年 | 308篇 |
2023年 | 1122篇 |
2022年 | 2901篇 |
2021年 | 4051篇 |
2020年 | 3351篇 |
2019年 | 2433篇 |
2018年 | 2552篇 |
2017年 | 2635篇 |
2016年 | 2271篇 |
2015年 | 3938篇 |
2014年 | 5261篇 |
2013年 | 5430篇 |
2012年 | 7718篇 |
2011年 | 8285篇 |
2010年 | 6558篇 |
2009年 | 5634篇 |
2008年 | 5949篇 |
2007年 | 5548篇 |
2006年 | 5395篇 |
2005年 | 4515篇 |
2004年 | 3002篇 |
2003年 | 2584篇 |
2002年 | 2119篇 |
2001年 | 1524篇 |
2000年 | 1389篇 |
1999年 | 1164篇 |
1998年 | 674篇 |
1997年 | 709篇 |
1996年 | 456篇 |
1995年 | 414篇 |
1994年 | 385篇 |
1993年 | 207篇 |
1992年 | 217篇 |
1991年 | 189篇 |
1990年 | 157篇 |
1989年 | 105篇 |
1988年 | 114篇 |
1987年 | 107篇 |
1986年 | 79篇 |
1985年 | 54篇 |
1984年 | 40篇 |
1983年 | 23篇 |
1982年 | 18篇 |
1981年 | 17篇 |
1980年 | 7篇 |
1979年 | 12篇 |
1973年 | 4篇 |
1972年 | 3篇 |
1966年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Nitric oxide: a revolution of free radicals theory of aging 总被引:1,自引:1,他引:0
Q H Bin 《Medical hypotheses》1991,34(1):60-61
There are two kinds of free radicals in the aging process, 'bad' and 'good'. Nitric oxide is a good free radical. 相似文献
22.
23.
24.
目的 比较文拉法辛与三环抗抑郁药治疗抑郁症临床痊愈率的差异。方法 应用循证医学的Me-ta分析,采用固定效应模型(fixed effects model,FEM)法对符合标准的16项对照研究文献进行评价。结果 文拉法辛与三环抗抑郁药治疗抑郁症的临床痊愈率不同,差异有显著性(χ2=4.773,df=1,P<0.05);综合的ORs=1.36,95%CI为1.04~1.78。提示文拉法辛治疗抑郁症的临床痊愈率是三环抗抑郁药的 1.36倍。结论 治疗抑郁症,文拉法辛比三环抗抑郁药有更可靠的临床痊愈率。 相似文献
25.
目的:研究肝细胞癌(hepatocellular carcinoma,HCC)经导管肝动脉化疗栓塞(transcatheter arterial chemoemboli-zation,TACE)后残癌组织细胞黏附分子CD44v6和ICAM-1(intercelluar adhesion molecule-1,ICAM-1)的表达情况。方法:经病理证实的HCC 50例,包括单纯手术切除30例(对照组),TACE术后行Ⅱ期手术切除20例(TACE组)。TACE组患者术前接受1~2次不等的TACE治疗,均按统一规范标准给予化疗药物灌注+栓塞治疗。对标本行免疫组织化学PV-9000染色,其中TACE组取病灶边缘残存肿瘤部分,检测肿瘤组织CD44v6和ICAM-1的表达,将两组结果进行对照分析。结果:对照组和TACE组CD44v6和ICAM-1均有不同程度的表达。对照组CD44v6表达阳性22例(22/30,73.33%),TACE组CD44v6表达阳性13例(13/20,65%),两者间无显著性差异(P>0.05);对照组ICAM-1表达阳性19例(19/30,63.33%),TACE组ICAM-1表达阳性12例(12/20,60%),两者间亦无显著性差异(P>0.05)。对照组和TACE组中CD44v6和ICAM-1表达间均呈正相关(P<0.05)。结论:TACE术后残癌组织CD44v6和ICAM-1仍有较高的表达,TACE并不能有效降低肝癌组织CD44v6和ICAM-1的表达;两者表达呈正相关。 相似文献
26.
血小板活化与冠心病关系的研究进展 总被引:3,自引:0,他引:3
病理性血小板活化与血栓性疾病密切相关,在心血管疾病中,这一病理生理过程不仅与冠心病的发生、发展有着非常重要的联系,而且对于该病的治疗策略的优化和近、远期预后等方面都有直接的影响。 相似文献
27.
28.
Hyung Bin Park Mihee Koh Se Hyun Cho Brian Hutchinson Bonghee Lee 《Journal of orthopaedic research》2005,23(6):1419-1424
The anterior cruciate ligament (ACL) serves as the primary restraint to anterior tibial translation. In addition to this biomechanical function, the ACL appears to have a function in neuromuscular control. This hypothesis was formulated after the discovery of mechanoreceptors within the ACL. The full somatosensory pathway from the ACL to the cerebrum has yet to be elucidated. In order to map this sensory pathway, we conducted a viral trans-synaptic tracing experiment using the neurotropic pseudorabies virus (PRV). The pseudorabies virus was injected into the ACL of rats and allowed to replicate and spread trans-synaptically for 6-7 days. The brain and spinal cord of each sacrificed rat was then removed and processed immunohistochemically to detect the presence of PRV. PRV-immunoreactive neurons were found to be localized in several different regions from the spinal cord to the cerebrum. Four nuclei in the reticular formation of the brain stem demonstrated strong positive labeling: the mesencephalic reticular nucleus, magnocellular reticular nucleus, paragigantocellular reticular nucleus, and gigantocellular reticular nucleus. This finding suggests that the nerve endings of the rat ACL project into the cerebrum and that the reticular formation may play an important role in the afferent pathway of those nerve endings. 相似文献
29.
A new Le Fort I internal distraction device in the treatment of severe maxillary hypoplasia. 总被引:2,自引:0,他引:2
Jaime Gateno Eric R Engel John F Teichgraeber Kyoko E Yamaji James J Xia 《Journal of oral and maxillofacial surgery》2005,63(1):148-154
PURPOSE: The purpose of this pilot study was to test a new Le Fort I internal distraction device. PATIENTS AND METHODS: A new internal Le Fort I distraction device designed by 1 of the authors was used in 3 patients with cleft lip and palate and severe maxillary hypoplasia who needed maxillary advancements in excess of 12 mm. Presurgical planning used CASSOS (SoftEnable Technology, Ltd, Hong Kong SAR, China) prediction tracing software and a stereolithographic model to calculate the distraction vector. The distractors were pre-bent and installed on the stereolithographic model and activated to advance the maxilla. Surgery was performed in a conventional manner, and distraction was started after a 7-day latency phase at the rate of 1 mm/day and continued until the presurgical plan was achieved. The distractor was removed after a 3-month consolidation phase. Cephalometric radiographs were taken at the completion of each phase. RESULTS: This new Le Fort I internal distraction device successfully distracted the maxillae as planned in all 3 patients. At the end of the distraction phase, the maxillary advancement was measured at 15.8 mm, 15.8 mm, and 13.5 mm, respectively. In each patient, a clockwise rotation of the maxilla was observed with a tendency to a posterior open bite. Postoperative radiographs also showed that the actual distraction vectors differed from the planned vectors. After the consolidation phase, radiographs showed a relapse of 2.6 mm, 0 mm, and 5.0 mm, respectively. There was no further relapse on 3-month follow-up radiographs. Each case showed radiographic evidence of excellent new bone formation at the osteotomy sites. CONCLUSION: The new Le Fort I internal distraction device produced the necessary advancement in all 3 patients. The study also showed that the actual distraction vector differed from the planned vector. This discrepancy was caused by a clockwise rotation of the maxilla during the distraction. Finally, the study showed a variable relapse rate not previously reported in maxillary distraction. 相似文献
30.
单甲氧聚乙二醇化学修饰药物酶的研究进展 总被引:4,自引:0,他引:4
用单甲氧基聚乙二醉(1)化学修饰药物酶是生化药物研究开发的重要手段之一。本文综述了1化学修饰药物酶的一般方法及修饰后酶在生物和理化性质方面的变化,同时对1研究前景进行展望,并指出了尚待解决的问题。 相似文献