全文获取类型
收费全文 | 24183篇 |
免费 | 1055篇 |
国内免费 | 116篇 |
专业分类
耳鼻咽喉 | 264篇 |
儿科学 | 483篇 |
妇产科学 | 253篇 |
基础医学 | 2988篇 |
口腔科学 | 684篇 |
临床医学 | 1497篇 |
内科学 | 6102篇 |
皮肤病学 | 280篇 |
神经病学 | 1890篇 |
特种医学 | 1024篇 |
外科学 | 4139篇 |
综合类 | 86篇 |
预防医学 | 731篇 |
眼科学 | 332篇 |
药学 | 1667篇 |
中国医学 | 34篇 |
肿瘤学 | 2900篇 |
出版年
2023年 | 141篇 |
2022年 | 271篇 |
2021年 | 437篇 |
2020年 | 253篇 |
2019年 | 313篇 |
2018年 | 441篇 |
2017年 | 322篇 |
2016年 | 397篇 |
2015年 | 431篇 |
2014年 | 561篇 |
2013年 | 705篇 |
2012年 | 1131篇 |
2011年 | 1219篇 |
2010年 | 761篇 |
2009年 | 674篇 |
2008年 | 1146篇 |
2007年 | 1184篇 |
2006年 | 1218篇 |
2005年 | 1202篇 |
2004年 | 1191篇 |
2003年 | 1201篇 |
2002年 | 1164篇 |
2001年 | 843篇 |
2000年 | 823篇 |
1999年 | 767篇 |
1998年 | 333篇 |
1997年 | 272篇 |
1996年 | 237篇 |
1995年 | 188篇 |
1994年 | 149篇 |
1993年 | 159篇 |
1992年 | 498篇 |
1991年 | 434篇 |
1990年 | 412篇 |
1989年 | 483篇 |
1988年 | 402篇 |
1987年 | 345篇 |
1986年 | 372篇 |
1985年 | 359篇 |
1984年 | 260篇 |
1983年 | 172篇 |
1982年 | 88篇 |
1980年 | 78篇 |
1979年 | 151篇 |
1978年 | 110篇 |
1977年 | 89篇 |
1975年 | 83篇 |
1974年 | 80篇 |
1969年 | 94篇 |
1967年 | 88篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Kusumi T Nishikawa S Tanaka M Ogawa T Jin H Sato F Toh S Hasegawa T Kijima H 《Pathology international》2005,55(12):802-806
Low-grade fibromyxoid sarcoma (LGFMS) is a rare tumor. Reported herein is a case of LGFMS arising in the big toe. The patient was a 58-year-old man who underwent excision of the tumor. The tumor was well-demarcated. Histologically, there were proliferating spindle-shaped tumor cells arranged in a whorled growth pattern, and the stroma showed hyalinized collagen bundles and a myxoid matrix. Nuclear mitotic figures were conspicuous in part. A large rosette-like structure with hyalinized stroma was found, which is characteristic of LGFMS. The differential diagnosis included tumor occurrence in adults; tending to arise in distal extremities; and having bland fibromyxoid histological features, such as fibroma of tendon sheath, low-grade myxofibrosarcoma and acral myxoinflammatory fibroblastic sarcoma. It was not possible to detect the FUS/CREB3L2 and FUS/CREB3L1 fusion genes from the formalin-fixed and paraffin-embedded tissue, although the histological features of the present case were typical of LGFMS. LGFMS may become more common with time, and unique cases may accumulate. 相似文献
102.
Sasaki J Sugawara K Tanno Y 《Shinrigaku kenkyu : The Japanese journal of psychology》2005,76(5):445-452
The aim of the present study is to explain why there is "the diverse U letter relationship" between embarrassment and psychological distance empirically, in view of Schlenker and Leary (1982)'s self-presentation model of social anxiety. In Study 1, those relationships were observed in three different situations. In Study 2, the main effect of motivation for avoiding rejection and the damage of self-image, and their interaction with embarrassment was examined by hierarchical regression analysis. In the first step, the psychological distance, in the second step, the main effect of both, and in the third step, the interaction was entered. As a result, in the second step, both main effects were significant, but in the third step, only interaction was significant, and both main effects were not significant. This showed that the interaction could predict embarrassment, although the psychological distance was controlled. Finally, this result was discussed in view of social norm. 相似文献
103.
Angiogenic endothelium-specific nestin expression is enhanced by the first intron of the nestin gene 总被引:5,自引:0,他引:5
Aihara M Sugawara K Torii S Hosaka M Kurihara H Saito N Takeuchi T 《Laboratory investigation; a journal of technical methods and pathology》2004,84(12):1581-1592
Nestin is a member of intermediate filaments abundantly expressed in neural stem cells and glioblastomas. The nestin gene has four exons and three introns, and neural cell-specific expression is regulated by the second intron. We previously reported that nestin was invariably detected in the tumor endothelium in gliomas even though tumor cells were negative for nestin. In the present study, we further confirmed nestin immunostaining in tumor endothelium of a variety of common cancers, including lung, stomach, colon, and cervical carcinomas. We examined an endothelium-specific regulator using human umbilical vein endothelial cells (HUVECs) and human glioblastoma-derived U251 cells. In a luciferase reporter assay, the first intron plus 5' upstream promoter (5'UP) gave the highest activity, followed by 5'UP, and the second intron plus 5'UP. However, the assay values were much lower by HUVEC extracts than by U251 cell extracts. Although green fluorescent protein expression was positive over all U251 cells under either the first intron, second intron, or ubiquitously active CAG promoter, the fluorescence in HUVECs was limited to a few cells even under the first intron. This difference came from the growth feature of HUVECs which exhibit growth arrest by contact inhibition. We found that the nestin expression was specific to proliferative endothelium, by using proliferation markers in hemangioblastomas and in situ hybridization. Using an endothelial tube formation assay, tyrosine kinase domain-deleted VEGF receptor KDR effectively abolished the tube formation under the first intron. We suggest that the nestin expression in tumor endothelium is enhanced by the first intron. 相似文献
104.
105.
106.
107.
Budipitojo T Sasaki M Matsuzaki S Cruzana MB Iwanaga T Kitamura N Yamada J 《Archives of histology and cytology》2003,66(4):337-346
Gastrin-releasing peptide (GRP) has been proposed as a novel regulatory peptide in the reproductive tract. We previously demonstrated that GRP immunoreactivities are found predominantly in the uterine gland epithelial cells of nonpregnant and pregnant cows. The present study focused on the distribution of GRP immunoreactivity and the expression of GRP mRNA in the bovine endometrium during the estrous cycle. Tissues were collected from 21 uterine horns and bodies during the estrous cycle. RT-PCR showed the expected GRP mRNA fragments (284 bp) in the tissues from all stages of the cycle. In situ hybridization results ascertained the expression of the GRP mRNA in the uterine gland epithelial cells and superficial epithelial cells of the endometrium. Positive staining of GRP immunoreactivity in the uterine gland epithelial cells was detected in both the uterine horn and body from all stages of the cycle. In metestrus and diestrus stages, GRP was also detected in the superficial epithelial cells of horn, but not in the body. The degrees of GRP mRNA expression and intensities of GRP immunoreactivity in the endometrium increased from proestrus to diestrus stages. These findings suggest that GRP may be important both in the endometrial remodeling during the estrous cycle and in the implantation and development of blastocysts. 相似文献
108.
Shinichiro Nanko Akira Ueki Mineko Hattori Xiao Y. Dai Tsukasa Sasaki Rimmei Fukuda Kazuhiko Ikeda Hajime Kazamatsuri 《American journal of medical genetics. Part A》1994,54(4):361-364
Parkinson's disease is thought to be caused by a combination of unknown environmental, genetic, and degenerative factors. Evidence from necropsy brain samples and pharmacokinetics suggests involvement of dopamine receptors in the pathogenesis or pathophysiology of Parkinson's disease. Genetic association studies between Parkinson's disease and dopamine D2, D3 and D4 receptor gene polymorphisms were conducted. The polymorphism was examined in 71 patients with Parkinson's disease and 90 controls. There were no significant differences between two groups in allele frequencies at the D2, D3, and D4 dopamine receptor loci. Our findings do not support the hypothesis that susceptibility to Parkinson's disease is associated with the dopamine receptor polymorphisms examined. © 1994 Wiley-Liss, Inc. 相似文献
109.
Glycogen storage disease type III with muscle involvement: reappraisal of phenotypic variability and prognosis. 总被引:1,自引:0,他引:1
T Momoi H Sano C Yamanaka H Sasaki H Mikawa 《American journal of medical genetics》1992,42(5):696-699
A review of the case histories of 19 Japanese patients with enzymatically proven glycogen storage disease (GSD) III who developed muscular symptoms at various ages illustrates the phenotypic variability of this disease. There seem to be 4 subgroups of GSD III with muscle involvement according to the clinical symptoms. The first group of patients is characterized by the childhood onset of muscle weakness and hepatic disorders. The second group of patients develops muscular symptoms in adult years while the liver symptoms start in childhood. The third group includes the patients whose muscle weakness started in adult years long after liver symptoms in childhood had disappeared. The fourth group shows only muscular symptoms as adults without any sign or history of liver dysfunction since childhood. The prognosis for each subgroup seems to be different; however, none of them appears to be better than that for GSD I, as has been suggested previously. 相似文献
110.