全文获取类型
收费全文 | 224090篇 |
免费 | 6098篇 |
国内免费 | 3277篇 |
专业分类
耳鼻咽喉 | 1663篇 |
儿科学 | 7257篇 |
妇产科学 | 3384篇 |
基础医学 | 21771篇 |
口腔科学 | 2741篇 |
临床医学 | 18754篇 |
内科学 | 37333篇 |
皮肤病学 | 1062篇 |
神经病学 | 18836篇 |
特种医学 | 10871篇 |
外国民族医学 | 26篇 |
外科学 | 33298篇 |
综合类 | 12174篇 |
现状与发展 | 12篇 |
一般理论 | 6篇 |
预防医学 | 21798篇 |
眼科学 | 4176篇 |
药学 | 14631篇 |
68篇 | |
中国医学 | 4042篇 |
肿瘤学 | 19562篇 |
出版年
2024年 | 187篇 |
2023年 | 703篇 |
2022年 | 1847篇 |
2021年 | 2431篇 |
2020年 | 1910篇 |
2019年 | 1579篇 |
2018年 | 23428篇 |
2017年 | 18801篇 |
2016年 | 20820篇 |
2015年 | 3082篇 |
2014年 | 3682篇 |
2013年 | 3516篇 |
2012年 | 10874篇 |
2011年 | 25085篇 |
2010年 | 21681篇 |
2009年 | 14110篇 |
2008年 | 22416篇 |
2007年 | 24620篇 |
2006年 | 3333篇 |
2005年 | 4674篇 |
2004年 | 4995篇 |
2003年 | 5994篇 |
2002年 | 3847篇 |
2001年 | 1385篇 |
2000年 | 1497篇 |
1999年 | 1040篇 |
1998年 | 749篇 |
1997年 | 733篇 |
1996年 | 465篇 |
1995年 | 452篇 |
1994年 | 389篇 |
1993年 | 222篇 |
1992年 | 273篇 |
1991年 | 264篇 |
1990年 | 279篇 |
1989年 | 205篇 |
1988年 | 194篇 |
1987年 | 163篇 |
1986年 | 138篇 |
1985年 | 124篇 |
1984年 | 67篇 |
1983年 | 60篇 |
1982年 | 56篇 |
1980年 | 61篇 |
1979年 | 63篇 |
1974年 | 66篇 |
1969年 | 60篇 |
1968年 | 53篇 |
1938年 | 61篇 |
1932年 | 58篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Zeyu Li Erwei Hao Rui Cao Si Lin Linghui Zou Tianyan Huang Zhengcai Du Xiaotao Hou Jiagang Deng 《中草药(英文版)》2022,14(4):479-493
Zedoary tumeric (Curcumae Rhizoma, Ezhu in Chinese) has a long history of application and has great potential in the treatment of liver cancer. The anti liver cancer effect of zedoary tumeric depends on the combined action of multiple pharmacodynamic substances. In order to clarify the specific mechanism of zedoary tumeric against liver cancer, this paper first analyzes the mechanism of its single pharmacodynamic substance against liver cancer, and then verifies the joint anti liver cancer mechanism of its "pharmacodynamic group". By searching the research on the anti hepatoma effect of active components of zedoary tumeric in recent years, we found that pharmacodynamic substances, including curcumol, zedoarondiol, curcumenol, curzerenone, curdione, curcumin, germacrone, β-elemene, can act on multi-target and multi-channel to play an anti hepatoma role. For example, curcumin can regulate miR, GLO1, CD133, VEGF, YAP, LIN28B, GPR81, HCAR-1, P53 and PI3K/Akt/mTOR, HSP70/TLR4 and NF-κB. Wnt/TGF/EMT, Nrf2/Keap1, JAK/STAT and other pathways play an anti hepatoma role. Network pharmacological analysis showed that the core targets of the "pharmacodynamic group" for anti-life cancer are AKT1, EGFR, MAPK8, etc, and the core pathways are neuroactive live receiver interaction, nitrogen metabolism, HIF-1 signaling pathway, etc. At the same time, by comparing and analyzing the relationship between the specific mechanisms of pharmacodynamic substance and "pharmacodynamic group", it is found that they have great reference significance in target, pathway, biological function, determination of core pharmacodynamic components, formation of core target protein interaction, in-depth research of single pharmacodynamic substance, increasing curative effect and so on. By analyzing the internal mechanism of zedoary tumeric pharmacodynamic substance and "pharmacodynamic group" in the treatment of liver cancer, this paper intends to provide some ideas and references for the deeper pharmacological research of zedoary tumeric and the relationship between pharmacodynamic substance and "pharmacodynamic group". 相似文献
2.
儿童晕厥临床诊治研究的发展与未来 总被引:1,自引:0,他引:1
儿童晕厥在临床常见,严重影响儿童的身心健康.儿童晕厥诊断关键技术的建立、诊断程序及个体化治疗新策略的提出,显著提高了儿童晕厥的诊治水平.基于研究成果,我国先后制定了多部儿童晕厥诊治指南与专家共识,并在国际期刊颁布了儿童和青少年晕厥指南,充分发挥了中国在国际儿童晕厥诊治领域的引领作用.今后尚需进一步开展儿童晕厥的流行病学研究,优化儿童晕厥预警体系以及干预与预防新策略,进一步推进儿童晕厥事业的发展. 相似文献
3.
Seyed Mehdi BagheriMofidi Majid Pouladian Seyed Behnamedin Jameie Ali Abbaspour Tehrani-Fard 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2016,39(3):717-726
Magnetic field generated by neuronal activity could alter magnetic resonance imaging (MRI) signals but detection of such signal is under debate. Previous researches proposed that magnitude signal change is below current detectable level, but phase signal change (PSC) may be measurable with current MRI systems. Optimal imaging parameters like echo time, voxel size and external field direction, could increase the probability of detection of this small signal change. We simulate a voxel of cortical column to determine effect of such parameters on PSC signal. We extended a laminar network model for somatosensory cortex to find neuronal current in each segment of pyramidal neurons (PN). 60,000 PNs of simulated network were positioned randomly in a voxel. Biot–savart law applied to calculate neuronal magnetic field and additional phase. The procedure repeated for eleven neuronal arrangements in the voxel. PSC signal variation with the echo time and voxel size was assessed. The simulated results show that PSC signal increases with echo time, especially 100/80 ms after stimulus for gradient echo/spin echo sequence. It can be up to 0.1 mrad for echo time = 175 ms and voxel size = 1.48 × 1.48 × 2.18 mm3. With echo time less than 25 ms after stimulus, it was just acquired effects of physiological noise on PSC signal. The absolute value of the signal increased with decrease of voxel size, but its components had complex variation. External field orthogonal to local surface of cortex maximizes the signal. Expected PSC signal for tactile detection in the somatosensory cortex increase with echo time and have no oscillation. 相似文献
4.
5.
6.
目的 对学龄期近视进展儿童进行调节功能的客观检查与分析,观察调节功能与近视进展之间的相关性。方法 选取2017年至2018年在首都医科大学附属北京同仁医院视光学门诊定期就诊的71名学龄期儿童为研究对象,根据受试者近年的屈光度进展速度,按≤0.50 D·a-1、>0.50~1.00 D·a-1、>1.00~1.50 D·a-1、>1.50 D·a-1分为4组,使用人眼调节分析仪对受试者进行调节功能的客观测量与分析,记录不同调节刺激视标下4组的客观调节反应值和客观调节微波动值,并作对比。结果 在所有调节视标上,各组随着调节刺激幅度增加,客观调节反应值也逐渐增加,4组在不同调节刺激视标下的客观调节反应值及平均的客观调节反应值差异均无统计学意义(均为P>0.05)。≤0.50 D·a-1、>0.50~1.00 D·a-1、>1.00~1.50 D·a-1、>1.50 D·a-1近视进展速度组调节微波动值分别为(62.2±5.6)D、(62.5±5.3)D、(66.5±6.0)D和(58.0±6.5)D,4组间差异有统计学意义(F=6.424,P=0.001),在+0.50~-0.50 D、-2.00 D调节刺激视标下,4组的客观调节微波动值比较差异均有统计学意义(均为P<0.05),在其余调节刺激视标下差异均无统计学意义(均为P>0.05)。结论 对于学龄期儿童的近视进展速度,客观调节微波动值相对于客观调节反应值可能是一个更为敏感的相关指标。 相似文献
7.
8.
Dan-Feng Xu Bing Wu Jin-Xin Wang Jian Yu Jian-Xin Xie 《World Journal of Clinical Cases》2021,9(5):1096-1102
BACKGROUNDGuillain-Barré syndrome (GBS) is a rare disorder that typically presents with ascending weakness, pain, paraesthesias, and numbness, which mimic the findings in lumbar spinal stenosis. Here, we report a case of severe lumbar spinal stenosis combined with GBS.CASE SUMMARYA 70-year-old man with a history of lumbar spinal stenosis presented to our emergency department with severe lower back pain and lower extremity numbness. Magnetic resonance imaging confirmed the diagnosis of severe lumbar spinal stenosis. However, his symptoms did not improve postoperatively and he developed dysphagia and upper extremity numbness. An electromyogram was performed. Based on his symptoms, physical examination, and electromyogram, he was diagnosed with GBS. After 5 d of intravenous immunoglobulin (0.4 g/kg/d for 5 d) therapy, he gained 4/5 of strength in his upper and lower extremities and denied paraesthesias. He had regained 5/5 of strength in his extremities when he was discharged and had no symptoms during follow-up.CONCLUSIONGBS should be considered in the differential diagnosis of spinal disorder, even though magnetic resonance imaging shows severe lumbar spinal stenosis. This case highlights the importance of a careful diagnosis when a patient has a history of a disease and comes to the hospital with the same or similar symptoms. 相似文献
9.
10.