全文获取类型
收费全文 | 1443篇 |
免费 | 120篇 |
国内免费 | 60篇 |
专业分类
耳鼻咽喉 | 12篇 |
儿科学 | 51篇 |
妇产科学 | 21篇 |
基础医学 | 139篇 |
口腔科学 | 31篇 |
临床医学 | 197篇 |
内科学 | 341篇 |
皮肤病学 | 23篇 |
神经病学 | 38篇 |
特种医学 | 306篇 |
外科学 | 158篇 |
综合类 | 37篇 |
预防医学 | 77篇 |
眼科学 | 11篇 |
药学 | 54篇 |
中国医学 | 28篇 |
肿瘤学 | 99篇 |
出版年
2021年 | 11篇 |
2019年 | 16篇 |
2018年 | 27篇 |
2017年 | 14篇 |
2015年 | 28篇 |
2014年 | 30篇 |
2013年 | 62篇 |
2012年 | 42篇 |
2011年 | 32篇 |
2010年 | 34篇 |
2009年 | 32篇 |
2008年 | 35篇 |
2007年 | 78篇 |
2006年 | 33篇 |
2005年 | 36篇 |
2004年 | 38篇 |
2003年 | 38篇 |
2002年 | 21篇 |
2001年 | 25篇 |
2000年 | 25篇 |
1999年 | 30篇 |
1998年 | 58篇 |
1997年 | 43篇 |
1996年 | 71篇 |
1995年 | 62篇 |
1994年 | 46篇 |
1993年 | 51篇 |
1992年 | 20篇 |
1991年 | 21篇 |
1990年 | 29篇 |
1989年 | 44篇 |
1988年 | 46篇 |
1987年 | 56篇 |
1986年 | 45篇 |
1985年 | 43篇 |
1984年 | 35篇 |
1983年 | 20篇 |
1982年 | 17篇 |
1981年 | 27篇 |
1980年 | 25篇 |
1979年 | 12篇 |
1978年 | 20篇 |
1977年 | 19篇 |
1976年 | 14篇 |
1975年 | 15篇 |
1974年 | 8篇 |
1973年 | 11篇 |
1972年 | 11篇 |
1970年 | 7篇 |
1968年 | 7篇 |
排序方式: 共有1623条查询结果,搜索用时 0 毫秒
1.
2.
Kevin G Becker Insong J Lee James W Nagle Rachel D Canning Ameer M Gado Rosarelis Torres Mihael H Polymeropoulos Paul T Massa WilliamE Biddison Paul D Drew 《International journal of developmental neuroscience》1997,15(7):73
We describe a novel human zinc finger cNDA, C2H2-171. This cDNA represents an mRNA which encodes a protein of 484 amino acids and a calculated molecular weight of 54 kD. Four zinc finger-like domains are found in the C-terminal end of the protein. At the N-terminus, C2H2-171 contains a POZ/tramtrack-like domain similar to that found in the tumor associated zinc finger proteins LAZ-3/BCL-6 and PLZ-F, as well as in non-zinc finger proteins. C2H2-171 RNA is preferentially expressed in the brain, and increases during the course of murine development, with maximal expression in the adult. C2H2-171 RNA is differentially expressed in brain regions, with the highest level of expression in the cerebellum. C2H2-171 RNA was expressed at high levels in primary cerebellar granule cell neurons compared to astrocytes. The gene encoding C2H2-171 is highly conserved in vertebrates, and maps to the terminus of human chromosome 1 (1q44-ter). This chromosomal location is associated with a number of cytogenetic aberrations including those involving brain developmental anomalies and tumorigenesis. These data suggest that C2H2-171 may play an important role in vertebrate brain development and function. 相似文献
3.
4.
Becker Kavin G.; Nagle James W.; Canning Rachel D.; Biddison William E.; Ozato Keiko; Drew Paul D. 《Human molecular genetics》1995,4(4):685-691
C2H2-type zinc finger genes comprise one of the largest genefamilies in the human genome. These proteins are involved ingenetic regulation and development and are quite conserved throughoutevolution. The finger domains commonly contain the small linkerpeptide TGEKP between some finger units. Here, we report theisolation of 133 human zinc finger cDNAs, of which 118 are novel.These clones were isolated from human brain cDNA libraries usingoligonucleotide hybridization followed by expressed sequencetag (EST) analysis, sequencing from the conserved linker regionusing degenerate oligonucleotide primers. This directed partialsequencing approach to cDNA isolation and characterization,signature sequencing, combines the speed of EST automatic sequencingwith the focus of specific cDNA family analysis. Signature sequencingminimizes the generation of less informative random EST sequencesand provides a unique relative position for sequence comparison.We also show that there is an even distribution of these RNA5from this brain cDNA library, and that these cDNAs contain N-terminaldomains found in other zinc finger genes. This rapid focusedsequencing approach should be applicable to any family of cDNAscontaining short conserved signature peptide sequences. 相似文献
5.
6.
D L Lennon E R Shrago M Madden F J Nagle P Hanson 《The American journal of clinical nutrition》1986,43(2):234-238
The purpose of this investigation was to determine if there was any relationship between dietary carnitine intake and the concentrations of carnitine in skeletal muscle and blood plasma in healthy adult men and women. Subjects (14 men, 14 women, fasted 8 h) reported to the Biodynamics Laboratory where they completed a 24-h diet recall questionnaire. Resting muscle biopsy (vastus lateralis) and blood plasma samples were taken and assayed for free, short-chain, and long-chain acyl carnitine concentrations. Dietary carnitine intake was estimated from data on concentrations in food. There was no significant relationship between either protein or carnitine intake with skeletal muscle carnitine concentrations. There was a significant relationship between both dietary carnitine (r = 0.50) and protein (r = 0.48) intake with blood plasma total acid soluble carnitine concentrations (p less than 0.01) in all subjects. 相似文献
7.
Dr. Smita K. Nagle Rajendra S. Kelkar 《Indian journal of otolaryngology and head and neck surgery》2007,59(1):41-42
Spirometry can be used as an objective tool for measuring nasal patency. it is sensitive, easy to perform, comfortable to patient The only limitation being that it only can be done in institution. 相似文献
8.
Genetic construction, expression, and melanoma-selective cytotoxicity of a diphtheria toxin-related alpha-melanocyte-stimulating hormone fusion protein. 总被引:16,自引:7,他引:9 下载免费PDF全文
J R Murphy W Bishai M Borowski A Miyanohara J Boyd S Nagle 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(21):8258-8262
The structural gene for diphtheria toxin, tox, has been modified at its Sph I site by the introduction of an oligonucleotide linker encoding a unique Pst I restriction endonuclease site and a synthetic oligonucleotide encoding alpha-melanocyte-stimulating hormone (alpha-MSH). The resulting fusion gene directs the expression of a diphtheria toxin-related alpha-MSH hybrid protein in which the diphtheria toxin receptor-binding domain has been replaced with alpha-MSH sequences. The chimeric toxin has been partially purified from periplasmic extracts of recombinant Escherichia coli K-12 and has been found to be selectively toxic for alpha-MSH receptor-positive human malignant melanoma NEL-M1 cells in vitro. 相似文献
9.
10.