全文获取类型
收费全文 | 74715篇 |
免费 | 8215篇 |
国内免费 | 4900篇 |
专业分类
耳鼻咽喉 | 595篇 |
儿科学 | 1270篇 |
妇产科学 | 681篇 |
基础医学 | 6719篇 |
口腔科学 | 1516篇 |
临床医学 | 9142篇 |
内科学 | 9454篇 |
皮肤病学 | 776篇 |
神经病学 | 3447篇 |
特种医学 | 3129篇 |
外国民族医学 | 27篇 |
外科学 | 7457篇 |
综合类 | 15944篇 |
现状与发展 | 13篇 |
一般理论 | 2篇 |
预防医学 | 6451篇 |
眼科学 | 1998篇 |
药学 | 8244篇 |
54篇 | |
中国医学 | 5793篇 |
肿瘤学 | 5118篇 |
出版年
2024年 | 311篇 |
2023年 | 1137篇 |
2022年 | 2844篇 |
2021年 | 3705篇 |
2020年 | 3002篇 |
2019年 | 2353篇 |
2018年 | 2421篇 |
2017年 | 2539篇 |
2016年 | 2305篇 |
2015年 | 3343篇 |
2014年 | 4267篇 |
2013年 | 4582篇 |
2012年 | 6401篇 |
2011年 | 6621篇 |
2010年 | 5119篇 |
2009年 | 4381篇 |
2008年 | 4810篇 |
2007年 | 4652篇 |
2006年 | 4426篇 |
2005年 | 3675篇 |
2004年 | 2996篇 |
2003年 | 2721篇 |
2002年 | 2156篇 |
2001年 | 1714篇 |
2000年 | 1280篇 |
1999年 | 955篇 |
1998年 | 512篇 |
1997年 | 566篇 |
1996年 | 404篇 |
1995年 | 332篇 |
1994年 | 308篇 |
1993年 | 189篇 |
1992年 | 145篇 |
1991年 | 135篇 |
1990年 | 120篇 |
1989年 | 90篇 |
1988年 | 84篇 |
1987年 | 71篇 |
1986年 | 57篇 |
1985年 | 28篇 |
1984年 | 19篇 |
1983年 | 22篇 |
1982年 | 7篇 |
1981年 | 5篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1970年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
13.
Yi Li Ying Chen Xiang Li Jian Wu Jing-Ying Pan Ri-Xin Cai Ri-Yun Yang Xiao-Dong Wang 《中国神经再生研究》2019,(9)
In the search for a therapeutic schedule for spinal cord injury, it is necessary to understand key genes and their corresponding regulatory networks involved in the spinal cord injury process. However, ad hoc selection and analysis of one or two genes cannot fully reveal the complex molecular biological mechanisms of spinal cord injury. The emergence of second-generation sequencing technology(RNA sequencing) has provided a better method. In this study, RNA sequencing technology was used to analyze differentially expressed genes at different time points after spinal cord injury in rat models established by contusion of the eighth thoracic segment. The numbers of genes that changed significantly were 944, 1362 and 1421 at 1, 4 and 7 days after spinal cord injury respectively. After gene ontology analysis and temporal expression analysis of the differentially expressed genes, C5ar1, Socs3 and CCL6 genes were then selected and identified by real-time polymerase chain reaction and western blot assay. The mRNA expression trends of C5ar1, Socs3 and CCL6 genes were consistent with the RNA sequencing results. Further verification and analysis of C5ar1 indicate that the level of protein expression of C5ar1 was consistent with its nucleic acid level after spinal cord injury. C5ar1 was mainly expressed in neurons and astrocytes. Finally, the gene Itgb2,which may be related to C5ar1, was found by Chilibot database and literature search. Immunofluorescence histochemical results showed that the expression of Itgb2 was highly consistent with that of C5ar1. Itgb2 was expressed in astrocytes. RNA sequencing technology can screen differentially expressed genes at different time points after spinal cord injury. Through analysis and verification, genes strongly associated with spinal cord injury can be screened. This can provide experimental data for further determining the molecular mechanism of spinal cord injury, and also provide possible targets for the treatment of spinal cord injury. This study was approved ethically by the Laboratory Animal Ethics Committee of Jiangsu Province, China(approval No. 2018-0306-001) on March 6, 2018. 相似文献
14.
Denise Lee Marcella D. Walker Hsin Yi Chen John A. Chabot James A. Lee Jennifer H. Kuo 《Surgery》2019,165(1):107-113
Background
Bone mineral density (BMD) has been found to improve after parathyroidectomy (PTX) in patients with primary hyperparathyroidism. There are few data on the effect of PTX on BMD in normocalcemic and normohormonal primary hyperparathyroidism.Methods
A retrospective analysis of 92 primary hyperparathyroidism patients who underwent PTX between 2004 and 2012 with pre- and post-PTX dual-energy x-ray absorptiometry was performed. Within-person changes in BMD pre- and post-PTX were analyzed using log linear mixed models, stratified by biochemical status.Results
Bone mineral density increased post-PTX in the whole cohort at the lumbar spine (+2.5%), femoral neck (+2.1%), and total hip (+1.9%) and decreased at the one-third radius (–0.9%). On comparison of BMD changes by profile, BMD increased in those with the typical profile at the lumbar spine (3.2%), femoral neck (2.9%), and total hip (2.9%) but declined at the one-third radius (–1.5%). In contrast, BMD improved only at the femoral neck (4.3%) in the normohormonal group and did not change at any site in the normocalcemic group. The typical group had a greater increase in BMD over time at the femoral neck and total hip compared with normocalcemic patients.Conclusion
Our results indicate that the skeletal benefit of PTX was attenuated in normocalcemic and normohormonal patients, suggesting that skeletal changes after PTX may depend on biochemical profile. 相似文献15.
Micro‐evolution of the hepatitis B virus genome in hepatitis B e‐antigen‐positive carriers: Comparison of genotypes B and C at various immune stages 下载免费PDF全文
16.
四妙勇安汤由金银花、玄参、当归、甘草4味药物组成,为《古代经典名方目录(第一批)》中100个经典名方之一。经溯源发现,四妙勇安汤源于《石室秘录》,后由《古今图书集成·医部全录》《验方新编》等书引用。从古代文献记载来看均有方无名,"四妙勇安汤"之名,最早见于1956年《中医治疗动脉栓塞性坏疽症的成效》,是由当时记者吕民报道河北省释迦宝山用"四妙勇安汤"治疗当地的动脉栓塞性坏疽时冠名。四妙勇安汤从方药组成与剂量上看,从《石室秘录》开始即是"金银花三两,当归二两,生甘草一两,玄参三两",历代版本《方剂学》确定四妙勇安汤金银花、玄参、当归、甘草的比例就是3∶3∶2∶1。而查阅文献,释迦宝山临证所用的四妙勇安汤由"玄参132 g,当归99 g,银花66 g,甘草33 g"组成,金银花、玄参、当归、甘草的比例变成2∶4∶3∶1。从治疗时间上看,原方记载的7日愈或是10日愈,而释迦宝山将其用到了三四个月,甚至五六个月。研究认为,古籍中的四妙勇安汤,应该是用于疾病的初期,尽早发现和治疗;而释迦宝山修改过的剂量,是广泛用于脱骨疽的中后期,甚至出现坏疽的严重病情所使用的,因此服药时间长,剂量大。且四妙勇安汤临证不仅限于治疗脱骨疽,也用于大头疮等,现代该方的使用已经大为拓展。相关研究已证实四妙勇安汤具有抗炎、稳定斑块、降脂、保护血管、改善血液流变学、抗凝、抑制血栓形成和促纤溶等作用,后续应开展君臣佐使辨析,对其临床应用范围重新进行界定。 相似文献
17.
18.
19.
20.