全文获取类型
收费全文 | 55048篇 |
免费 | 3271篇 |
国内免费 | 1528篇 |
专业分类
耳鼻咽喉 | 391篇 |
儿科学 | 964篇 |
妇产科学 | 668篇 |
基础医学 | 4468篇 |
口腔科学 | 1037篇 |
临床医学 | 5075篇 |
内科学 | 5709篇 |
皮肤病学 | 475篇 |
神经病学 | 3112篇 |
特种医学 | 1268篇 |
外国民族医学 | 6篇 |
外科学 | 5559篇 |
综合类 | 10454篇 |
现状与发展 | 1篇 |
一般理论 | 6篇 |
预防医学 | 5378篇 |
眼科学 | 934篇 |
药学 | 4624篇 |
116篇 | |
中国医学 | 7948篇 |
肿瘤学 | 1654篇 |
出版年
2024年 | 207篇 |
2023年 | 981篇 |
2022年 | 1745篇 |
2021年 | 2299篇 |
2020年 | 2124篇 |
2019年 | 2259篇 |
2018年 | 1911篇 |
2017年 | 1769篇 |
2016年 | 1650篇 |
2015年 | 1422篇 |
2014年 | 3447篇 |
2013年 | 3066篇 |
2012年 | 3057篇 |
2011年 | 3846篇 |
2010年 | 3533篇 |
2009年 | 2580篇 |
2008年 | 2391篇 |
2007年 | 2603篇 |
2006年 | 2421篇 |
2005年 | 1997篇 |
2004年 | 1620篇 |
2003年 | 1508篇 |
2002年 | 1023篇 |
2001年 | 917篇 |
2000年 | 757篇 |
1999年 | 691篇 |
1998年 | 534篇 |
1997年 | 509篇 |
1996年 | 410篇 |
1995年 | 460篇 |
1994年 | 427篇 |
1993年 | 327篇 |
1992年 | 321篇 |
1991年 | 288篇 |
1990年 | 248篇 |
1989年 | 242篇 |
1988年 | 247篇 |
1987年 | 204篇 |
1986年 | 197篇 |
1985年 | 419篇 |
1984年 | 409篇 |
1983年 | 325篇 |
1982年 | 357篇 |
1981年 | 354篇 |
1980年 | 342篇 |
1979年 | 304篇 |
1978年 | 270篇 |
1977年 | 244篇 |
1976年 | 182篇 |
1975年 | 108篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Molecular and biological analysis of echovirus 9 strain isolated from a diabetic child 总被引:2,自引:0,他引:2
Paananen A Ylipaasto P Rieder E Hovi T Galama J Roivainen M 《Journal of medical virology》2003,69(4):529-537
The full-length infectious cDNA clone was constructed and sequenced from the strain DM of echovirus 9, which was recently isolated from a 6-week-old child at the clinical onset of type 1 diabetes. Parallel with the isolate DM, the full-length infectious cDNA clone of the prototype strain echovirus 9 Barty (Barty-INF), was constructed and sequenced. Genetic relationships of the sequenced echo 9 viruses to the other members of the human enterovirus type B species were studied by phylogenetic analyses. Comparison of capsid protein sequences showed that the isolate DM was closely related to both prototype strains: Hill and Barty-INF. The only exception was the inner capsid protein VP4 where serotype specificity was not evident and the isolate DM clustered with the strain Hill and the strain Barty-INF with echovirus 30 Bastianni. Likewise, the nonstructural protein coding region, P2P3, of isolate DM was more similar to strain Hill than to strain Barty-INF. However, like echovirus 9 Barty, the isolate DM contained the RGD-motif in the carboxy terminus of capsid protein VP1. By blocking experiments using an RGD-containing peptide and a polyclonal rabbit antiserum to the alpha(v)beta(3)-integrin, it was shown that this molecule works as a cellular receptor for isolate DM. By using primary human islets, it was shown that the isolate DM is capable of infecting insulin-producing beta-cells like the corresponding prototype strains did. However, only isolate DM was clearly cytolytic for beta-cells. The infectious clones that were made allow further investigations of the molecular features responsible for the diabetogenicity of the isolate DM. 相似文献
72.
目的分析应用Orthofix-微型器治疗第一掌骨基底部Bennett骨折的临床疗效。方法收集2009年1月~2013年1月我院31例采用Orthofix-微型器治疗的第一掌骨基底部Bennett骨折患者。记录患者年龄、性别等基线资料,以及术后上肢臂、肩、手功能调查量表(Disabilities of the arm,shoulder and hand,DASH)评分,随访终末期采用指总关节活动度(Total action movement,TAM)评分。结果随访6~24个月,平均14.4月,手术时间为18~40分钟,平均29.1分钟,术中出血量10~30m L,平均14.5m L。术后3月、术后6月及终末期DASH评分之间比较,差异均有统计学意义(0.05)。随访终末期,其中26例解剖复位,5例骨折对线良好,TAM评分优22例,良7例,差2例。随访期间未发生桡神经浅支损伤、钉道感染等并发症。结论 Orthofix-微型外固定器治疗Bennett骨折操作简单、疗效满意。 相似文献
73.
将白细胞介素-1(IL)注入大鼠侧脑室,用Fos癌蛋白抗体免疫组化法检测了下丘脑室旁核的激活神经元:大量位于含促肾上腺皮质激素释放因子(CRF)相应区域的室旁核小细胞部神经元呈Fos免疫强阳性。Fos和CRF的免疫双染色显示了许多Fos免疫阳性神经元也呈CRF免疫阳性。此外,在IL-1注射动物中,CRF的免疫阳性显著加强,提示CRF合成增加。 相似文献
74.
张渡淮 《生物医学工程学杂志》1995,12(1):64-66
伊·普利高津的耗散结构理论中,有一个著名的总熵变公式ds=dse+dsi把上述公式用于人体研究,国内外尚未见报导。在前人对人体热力学系统研究的基础上,本文建立了一个人体熵流的数学模型,为进一步展开研究,提供了有力工具并奠定了可靠的理论基础。 相似文献
75.
Retrograde transport of horseradish peroxidase injected iontophoretically into the nucleus of the optic tract of cats revealed that the direction-selective cells in this pretectal nucleus receive direct retinal projections from small retinal ganglion cells, the so-called gamma-cells. These cells from a horizontal band on the contralateral retina. Few labeled cells are found in the ipsilateral temporal retina. The input from the contralateral retina is 10 times more numerous than from the ipsilateral one. In both retinae the highest concentration of labeled cells is near the area centralis. 相似文献
76.
77.
R. Tateishi K. Taniguchi T. Horai T. Iwanaga H. Taniguchi T. Kabuto M. Sano S. Ishiguro A. Wada 《Virchows Archiv : an international journal of pathology》1976,371(4):283-294
Summary In a series of 79 cases of primary esophageal carcinoma resected at The Center for Adult Diseases, Osaka, there were six tumors with specific histopathologic features valid for the diagnosis of argyrophil cell carcinoma. Of the 6 tumors, 3 were studied electron microscopically and assay for ACTH content was performed on 4 tumors.Clinically, the ages of the 6 patients ranged from 56 to 71 years; two were women and four men. Four of the 6 patients died with widespread tumor recurrences within 9 months of operation.Microscopically, the 6 tumors were composed largely or almost entirely of small, spindle-shaped cells resembling those of oat cell carcinoma of the lung, and were characterized by the arrangement of tumor cells in solid sheets or anastomosing cords, the presence of argyrophil tumor cells, and the deposits of amyloid. Electron microscopically, the three tumors contained neurosecretory-type granules. Using bioassay or radioimmunoassay ACTH activity in the tumor tissues was detected in 3 out of the 4 tumors determined.From the light and electron microscopic characteristics and the assay evidence, it seems reasonable to conclude that the 6 tumors are endocrine polypeptide producing tumors (apudomas) that arise from argyrophil cells normally found among the basal cells of the esophageal mucosa, and that they represent a distinct histopathologic entity clearly distinguishable from other types of esophageal carcinomas.Supported in part by a Grant-in Aid for Cancer Research from the Ministry of Education, Science and Culture, and the Ministry of Health and Welfare, JapanThe authors are grateful to Prof. H. Imura and Dr. Y. Hirate, Department of Internal Medicine, Kobe University School of Medicine for their interest and performing the assays for ACTH on the tumor tissues. 相似文献
78.
The Thy-1 antigens or rat brain and thymus have been isolated and chemically characterized, but those of mice have not been identified. Moreover, it is uncertain whether the antigens are glycolipids or glycoproteins. This study with highly purified preparations of gangliosides GM1, 1GD1a, GD1b and GT1b from bovine brain and several ganglioside fractions from mouse brain showed that Thy-1 activity does not reside in gangliosides, but rather in the chloroform-methanol-insoluble residue of brain remaining after extraction of gangliosides. The antigen could be solubilized from this residue with a non-ionic detergent. The antigenic activity of the solubilized preparation was heat-labile but resistant to periodate. The chemical properties of the Thy-1 antigen of mouse brain are discussed. 相似文献
79.
耳穴电参数时变关系实验表明,在测量起始t<2τ时,因瞬变作用,电位E(t)和压降U(t)为瞬态响应,响应函数呈指数关系,特征参数为弛豫时间τ,τ≈RC;t>2τ时,为时变间期。电路分析给出数学描述,并与耳穴和模拟实验结果较相符。提示,时变特征应以t>2τ后提取,静态电测量时,采样应避开瞬变期,可提高准确性。该工作对正确鉴别时变性和特征提取,全面认识耳穴电特性具有重要意义。 相似文献
80.