全文获取类型
收费全文 | 1747篇 |
免费 | 62篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 85篇 |
妇产科学 | 29篇 |
基础医学 | 225篇 |
口腔科学 | 36篇 |
临床医学 | 120篇 |
内科学 | 318篇 |
皮肤病学 | 26篇 |
神经病学 | 191篇 |
特种医学 | 46篇 |
外科学 | 152篇 |
综合类 | 134篇 |
一般理论 | 1篇 |
预防医学 | 78篇 |
眼科学 | 32篇 |
药学 | 195篇 |
中国医学 | 55篇 |
肿瘤学 | 83篇 |
出版年
2023年 | 13篇 |
2022年 | 14篇 |
2021年 | 27篇 |
2020年 | 34篇 |
2019年 | 124篇 |
2018年 | 92篇 |
2017年 | 61篇 |
2016年 | 45篇 |
2015年 | 44篇 |
2014年 | 115篇 |
2013年 | 69篇 |
2012年 | 90篇 |
2011年 | 115篇 |
2010年 | 88篇 |
2009年 | 70篇 |
2008年 | 88篇 |
2007年 | 72篇 |
2006年 | 55篇 |
2005年 | 38篇 |
2004年 | 32篇 |
2003年 | 30篇 |
2002年 | 37篇 |
2001年 | 17篇 |
2000年 | 10篇 |
1999年 | 12篇 |
1998年 | 11篇 |
1997年 | 10篇 |
1996年 | 7篇 |
1995年 | 9篇 |
1994年 | 5篇 |
1993年 | 9篇 |
1992年 | 11篇 |
1991年 | 7篇 |
1990年 | 3篇 |
1988年 | 3篇 |
1987年 | 6篇 |
1986年 | 2篇 |
1985年 | 22篇 |
1984年 | 62篇 |
1983年 | 28篇 |
1982年 | 34篇 |
1981年 | 26篇 |
1980年 | 36篇 |
1979年 | 33篇 |
1978年 | 17篇 |
1977年 | 18篇 |
1976年 | 18篇 |
1975年 | 15篇 |
1974年 | 20篇 |
1973年 | 18篇 |
排序方式: 共有1826条查询结果,搜索用时 31 毫秒
1.
2.
PRO 1000 V3型心电监护仪LCD逆变器的升级及注意事项 总被引:1,自引:0,他引:1
介绍了该型心电监护仪黑屏故障的常见原因,对升级前后的LCD逆变器电路作了对比分析,并详细介绍了升级更换的方法和注意事项。 相似文献
3.
4.
5.
6.
Methodological Studies on Genomic DNA Extraction and Purification from Plant Drug Materials 总被引:17,自引:0,他引:17
本文探讨了菊科9种植物和地胆草的4种对口商品药材基因组DNA提取与纯化的原理、方法通过对3种常用植物基因组DNA提取方法(CsCl梯度超速离心法、CTABCsCl梯度超速离心法和CTAB微量提取法)的条件摸索在DNA产率、纯度以及提取纯化过程中影响PCR扩增因子方面进行比较,认为CTAB微量提取法是植物类药材基因组DNA一种比较省时、有效、经济的提取方法 相似文献
7.
Wistar大鼠随机分3组,每天组予环磷酰胺组(CP)8mg/kg·d×4W,ip;冲击组予CP56mg/kg·d×4W,ip;对照组予生理盐水1ml/d×4W,ip。结果:①睾丸生精细胞损伤:每日组重于冲击组;②血睾酮(T)含量每日组显著低于冲击组(P<0.05);冲击组与对照组无显著差异(P>0.05)。③对睾丸间质细胞的影响:冲击组轻于每日组;④血FSH、LH含量与垂体重量:每日组与冲击组皆正常;⑤血BUN、Cr水平:3组皆正常.说明CP冲击疗法对睾丸间质细胞损伤较轻;CP除直接损伤睾丸组织外,可能还对下丘脑—垂体—睾丸轴有抑制作用. 相似文献
8.
Lois J. Starr Jürgen W. Spranger Vamshi K. Rao Richard Lutz Anji T. Yetman 《American journal of medical genetics. Part A》2019,179(7):1270-1275
PIGQ (OMIM *605754) encodes phosphatidylinositol glycan biosynthesis class Q (PIGQ) and is required for proper functioning of an N‐acetylglucosamine transferase complex in a similar manner to the more established PIGA, PIGC, and PIGH. There are two previous patients reported with homozygous and apparently deleterious PIGQ mutations. Here, we provide the first detailed clinical report of a patient with heterozygous deleterious mutations associated with glycosylphosphatidylinositol‐anchored protein (GPI‐AP) biosynthesis deficiency. Our patient died at 10 months of age. The rare skeletal findings in this disorder expand the differential diagnosis of long bone radiolucent lesions and sphenoid wing dysplasia. This clinical report describes a new and rare disorder—PIGQ GPI‐AP biosynthesis deficiency syndrome. 相似文献
9.
Responses of lateral medullary neurons to microstimulation of two points in the locomotor strip—rostral and caudal to the obex—were recorded intracellularly in mesencephalic decerebellated uncurarized cats. Excitatory and inhibitory postsynaptic potentials and orthodromic action potentials occurred up to 20 ms after a single stimulus. A number of cells responded to stimulation of a locomotor point by a repetitive discharge, and in some cells synaptic responses were evoked by contralateral stimulation. The responsive neurons were scattered among other cells in the lateral medullary tegmentum. At least one-third of neurons with synaptic responses to stimulation of the rostral locomotor point were antidromically invaded from the caudal one. The characteristic length of these descending axons was between 4 and 9 mm, although there were longer axons too.The lateral medullary cells which give synaptic responses to stimulation of the locomotor strip form the locomotor column located medial to the strip, and a portion of these cells send their axons to the strip. It is suggested that the activity is propagated polysynaptically along the column through axonal collaterals of its neurons. One can assume that when repetitive stimulation achieves a threshold for locomotion such a propagation occurs without decrement. As a result, spinal stepping generators are activated. 相似文献
10.
A. Caignard M. Guillard Z. Cai C. Asselin-Paturel G. Carayol S. Chouaib 《Tissue antigens》1996,48(4):295-300
The expression of Fas antigen at the surface of renal cell carcinoma and the susceptibility to Fas-mediated lysis by a tumor specific CTL clone were investigated. Renal cell carcinoma cell lines expressed Fas antigen and were susceptible to apoptosis mediated by antibodies to Fas/APO1. Using RT-PCR, we further showed that these cell lines expressed mRNA for Fas deleted transmembrane region, corresponding to a soluble form of Fas/APO-1. To investigate the role of the Fas/FasL pathway in the cytotoxic response against RCC cells, we analyzed the induction of Fas-L on a tumor specific T cell clone (CTL 8C2), previously generated against one RCC cell line. Fas-L expression on CTL 8C2 was detected by RT-PCR after stimulation with autologous tumor cells. However, the cytotoxic activity of CTL 8C2 was completely abolished when EGTA was added, suggesting that the cytolysis was mainly mediated by a Ca++-dependent pathway, perforin/granzyme-based. 相似文献