全文获取类型
收费全文 | 10445篇 |
免费 | 519篇 |
国内免费 | 123篇 |
专业分类
耳鼻咽喉 | 176篇 |
儿科学 | 290篇 |
妇产科学 | 101篇 |
基础医学 | 1816篇 |
口腔科学 | 192篇 |
临床医学 | 960篇 |
内科学 | 2086篇 |
皮肤病学 | 242篇 |
神经病学 | 577篇 |
特种医学 | 830篇 |
外科学 | 1188篇 |
综合类 | 43篇 |
一般理论 | 2篇 |
预防医学 | 397篇 |
眼科学 | 270篇 |
药学 | 962篇 |
1篇 | |
中国医学 | 93篇 |
肿瘤学 | 861篇 |
出版年
2023年 | 66篇 |
2022年 | 245篇 |
2021年 | 372篇 |
2020年 | 188篇 |
2019年 | 216篇 |
2018年 | 290篇 |
2017年 | 226篇 |
2016年 | 281篇 |
2015年 | 437篇 |
2014年 | 544篇 |
2013年 | 602篇 |
2012年 | 798篇 |
2011年 | 772篇 |
2010年 | 489篇 |
2009年 | 471篇 |
2008年 | 558篇 |
2007年 | 607篇 |
2006年 | 535篇 |
2005年 | 466篇 |
2004年 | 335篇 |
2003年 | 313篇 |
2002年 | 249篇 |
2001年 | 220篇 |
2000年 | 220篇 |
1999年 | 202篇 |
1998年 | 146篇 |
1997年 | 154篇 |
1996年 | 137篇 |
1995年 | 95篇 |
1994年 | 101篇 |
1993年 | 125篇 |
1992年 | 51篇 |
1991年 | 45篇 |
1990年 | 44篇 |
1989年 | 66篇 |
1988年 | 55篇 |
1987年 | 48篇 |
1986年 | 47篇 |
1985年 | 43篇 |
1984年 | 21篇 |
1983年 | 21篇 |
1982年 | 24篇 |
1981年 | 36篇 |
1980年 | 21篇 |
1979年 | 14篇 |
1978年 | 14篇 |
1977年 | 25篇 |
1976年 | 22篇 |
1975年 | 9篇 |
1968年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
32.
Inhibition of p38MAP kinase suppresses fibrotic reaction of retinal pigment epithelial cells 总被引:3,自引:0,他引:3
33.
Lee YJ Hohoff C Domschke K Sand P Kuhlenbäumer G Schirmacher A Freitag CM Meyer J Stöber G Franke P Nöthen MM Fritze J Fimmers R Garritsen HS Stögbauer F Deckert J 《Neuroscience letters》2005,377(1):40-43
Several biochemical and pharmacological studies suggest that the catecholaminergic system involving the norepinephrine transporter (NET) is relevant for the pathogenesis of panic disorder. Three single nucleotide polymorphisms in the promoter or untranslated 5' region of the NET gene were investigated by means of RFLP analysis in a sample of 115 German patients with panic disorder and 115 matched controls. Statistical analysis failed to show association with the overall diagnosis of panic disorder. In the subgroup of patients with panic disorder without agoraphobia, however, two polymorphisms were found to be associated with the disease (G/C (rs2397771): p < 0.05; T/C (rs2242446): p < 0.01). While our data do not support a major function of the NET gene in the development of panic disorder, it may play a role in the subgroup of panic disorder without agoraphobia. 相似文献
34.
Loss of heterozygosity on chromosomes 3p,8p,9p and 17p in the progression of squamous cell carcinoma of the larynx 总被引:4,自引:0,他引:4
Yoo WJ Cho SH Lee YS Park GS Kim MS Kim BK Park WS Lee JY Kang CS 《Journal of Korean medical science》2004,19(3):345-351
Previous molecular genetic studies of laryngeal squamous cell carcinoma (SCC)have shown certain chromosomal regions with recurring alterations. But studies of sequential molecular alterations and genetic progression model of laryngeal SCC have not been clearly defined. To identify the chromosomal alterations associated with the carcinogenesis of laryngeal SCC, we analyzed genomic DNA from microdissected squamous metaplasia, squamous dysplasia, invasive SCC, and metastatic carcinoma samples from 22 laryngeal SCC patients for loss of heterozygosity (LOH) at microsatellite loci. Ten microsatellite markers on chromosome 3p, 8p, 9p, and 17p were used. LOH at 9p21 was observed in the all stages including squamous metaplasia, squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 17p13.1, 3p25 and 3p14.2 was observed from the squamous dysplasia, invasive SCC and metastatic carcinoma. LOH at 8p21.3-p22 was observed mainly from the invasive SCC and metastatic carcinoma. The results suggest that 9p21 in the early event, 17p13.1, 3p25 and 3p14.2 in the intermediate event and 8p21.3- p22 in the late event may be involved in the laryngeal carcinogenesis. 相似文献
35.
Variability of skin temperature in the waking monkey 总被引:3,自引:0,他引:3
36.
37.
Xanthii Fructus (XF) is an herb widely used in medicine for the treatment of a variety of inflammatory pathologies. In this study, using mouse peritoneal macrophages, we have examined whether XF affects nitric oxide (NO), tumor necrosis factor (TNF)-α, and interleukin (IL)-12p40 production induced by interferon (IFN)-γ and lipopolysaccharide (LPS). XF inhibits IFN-γ and LPS-induced NO production in a dose dependent manner. The decrease in NO synthesis was reflected as a decreased amount of inducible NO synthase protein. Furthermore, we also found that XF inhibits pro-inflammatory cytokine TNF-α production. However, treatment of XF in peritoneal macrophages had no effect on IL-12p40 production. These findings suggest that XF may be used in controlling macrophages-mediated inflammatory diseases. 相似文献
38.
39.
Haijo Jung Hee-Joung Kim Sang-Ho Lee Sae-Rome Kim Chang Lyong Ji Jung-Han Kim Sun Kook Yoo Ki-Hwang Kim 《Journal of digital imaging》2004,17(2):100-108
This study evaluated the migration to full-PACS of medical image data archived using mini-PACS at two hospitals of the Yonsei University Medical Center, Seoul, Korea. A major concern in the migration of medical data is to match the image data from the mini-PACS with the hospital OCS (Ordered Communication System). Prior to carrying out the actual migration process, the principles, methods, and anticipated results for the migration with respect to both cost and effectiveness were evaluated. Migration gateway workstations were established and a migration software tool was developed. The actual migration process was performed based on the results of several migration simulations. Our conclusions were that a migration plan should be carefully prepared and tailored to the individual hospital environment because the server system, archive media, network, OCS, and policy for data management may be unique. 相似文献
40.
Implantation of bone marrow mononuclear cells using injectable fibrin matrix enhances neovascularization in infarcted myocardium 总被引:11,自引:0,他引:11
Ryu JH Kim IK Cho SW Cho MC Hwang KK Piao H Piao S Lim SH Hong YS Choi CY Yoo KJ Kim BS 《Biomaterials》2005,26(3):319-326
Neovascularization may improve cardiac function and prevent further scar tissue formation in infarcted myocardium. A number of studies have demonstrated that bone marrow-derived cells have the potential to induce neovascularization in ischemic tissues. In this study, we hypothesized that implantation of bone marrow mononuclear cells (BMMNCs) using injectable fibrin matrix further enhances neovascularization in infarcted myocardium compared to BMMNC implantation without matrix. To test this hypothesis, infarction was induced in rat myocardium by cryoinjury. Three weeks later, rat BMMNCs were mixed with fibrin matrix and injected into the infarcted myocardium. Injection of either BMMNCs or medium alone into infarcted myocardium served as controls. Eight weeks after the treatments, histological analyses indicated that implantation of BMMNCs using fibrin matrix resulted in more extensive tissue regeneration in the infarcted myocardium compared to BMMNC implantation without matrix. Examination with fluorescence microscopy revealed that cells labeled with a fluorescent dye prior to implantation survived in the infarcted myocardium at 8 weeks of implantation. Importantly, implantation of BMMNCs using fibrin matrix resulted in much more extensive neovascularization in infarcted myocardium than BMMNC implantation without matrix. The microvessel density in infarcted myocardium was significantly higher (p < 0.05) when BMMNCs were implanted using fibrin matrix (350 +/- 22 microvessels/mm2) compared to BMMNC implantation without matrix (262 +/- 13 microvessels/mm2) and medium injection (76 +/- 9 microvessels/mm2). In addition, average internal diameter of microvessels was significantly larger (p < 0.05) in BMMNC implantation with fibrin matrix group (14.6 +/- 1.2 microm) than BMMNC implantation without matrix group (10.2 +/- 0.7 microm) and medium injection group (7.3 +/- 0.5 microm). These results suggest that fibrin matrix could serve as a cell implantation matrix that enhances neovascularization efficacy for myocardial infarction treatment. 相似文献