全文获取类型
收费全文 | 91篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
现状及发展 | 18篇 |
研究方法 | 17篇 |
综合类 | 52篇 |
自然研究 | 5篇 |
出版年
2014年 | 1篇 |
2012年 | 3篇 |
2011年 | 7篇 |
2009年 | 1篇 |
2008年 | 4篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 2篇 |
2004年 | 4篇 |
2003年 | 2篇 |
2002年 | 4篇 |
2001年 | 2篇 |
2000年 | 5篇 |
1999年 | 3篇 |
1995年 | 1篇 |
1992年 | 5篇 |
1991年 | 1篇 |
1988年 | 1篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 8篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 4篇 |
1976年 | 3篇 |
1974年 | 3篇 |
1973年 | 3篇 |
1971年 | 1篇 |
1969年 | 1篇 |
1967年 | 1篇 |
1966年 | 2篇 |
排序方式: 共有92条查询结果,搜索用时 15 毫秒
51.
The LAR-family protein tyrosine phosphatase sigma (PTPsigma, encoded by the gene Ptprs) consists of a cell adhesion-like extracellular domain composed of immunoglobulin and fibronectin type-III repeats, a single transmembrane domain and two intracellular catalytic domains. It was previously shown to be expressed in neuronal and lung epithelial tissues in a developmentally regulated manner. To study the role of PTPsigma in mouse development, we inactivated Ptprs by gene targeting. All Ptprs+/- mice developed normally, whereas 60% of Ptprs-/- mice died within 48 hours after birth. The surviving Ptprs-/- mice demonstrated stunted growth, developmental delays and severe neurological defects including spastic movements, tremor, ataxic gait, abnormal limb flexion and defective proprioception. Histopathology of brain sections revealed reduction and hypocellularity of the posterior pituitary of Ptprs-/- mice, as well as a reduction of approximately 50-75% in the number of choline acetyl transferase-positive cells in the forebrain. Moreover, peripheral nerve electrophysiological analysis revealed slower conduction velocity in Ptprs-/- mice relative to wild-type or heterozygous animals, associated with an increased proportion of slowly conducting, small-diameter myelinated fibres and relative hypomyelination. By approximately three weeks of age, most remaining Ptprs-/- mice died from a wasting syndrome with atrophic intestinal villi. These results suggest that PTPsigma has a role in neuronal and epithelial development in mice. 相似文献
52.
H. Wallace 《Cellular and molecular life sciences : CMLS》1978,34(10):1360-1361
Summary Contrary to the predictions of the clockface model, rotating a regenerate by 90° produces duplications identical to those resulting from 180° axial reversals. Exchanging regenerates between arms indicates the presence of 2 determined transverse axes. 相似文献
53.
Weedon MN Lango H Lindgren CM Wallace C Evans DM Mangino M Freathy RM Perry JR Stevens S Hall AS Samani NJ Shields B Prokopenko I Farrall M Dominiczak A;Diabetes Genetics Initiative;Wellcome Trust Case Control Consortium Johnson T Bergmann S Beckmann JS Vollenweider P Waterworth DM Mooser V Palmer CN Morris AD Ouwehand WH;Cambridge GEM Consortium Zhao JH Li S Loos RJ Barroso I Deloukas P Sandhu MS Wheeler E Soranzo N Inouye M Wareham NJ Caulfield M Munroe PB Hattersley AT McCarthy MI Frayling TM 《Nature genetics》2008,40(5):575-583
Adult height is a model polygenic trait, but there has been limited success in identifying the genes underlying its normal variation. To identify genetic variants influencing adult human height, we used genome-wide association data from 13,665 individuals and genotyped 39 variants in an additional 16,482 samples. We identified 20 variants associated with adult height (P < 5 x 10(-7), with 10 reaching P < 1 x 10(-10)). Combined, the 20 SNPs explain approximately 3% of height variation, with a approximately 5 cm difference between the 6.2% of people with 17 or fewer 'tall' alleles compared to the 5.5% with 27 or more 'tall' alleles. The loci we identified implicate genes in Hedgehog signaling (IHH, HHIP, PTCH1), extracellular matrix (EFEMP1, ADAMTSL3, ACAN) and cancer (CDK6, HMGA2, DLEU7) pathways, and provide new insights into human growth and developmental processes. Finally, our results provide insights into the genetic architecture of a classic quantitative trait. 相似文献
54.
David Wallace 《Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics》2002,33(4)
This is a discussion of how we can understand the world-view given to us by the Everett interpretation of quantum mechanics, and in particular the rôle played by the concept of ‘world’. The view presented is that we are entitled to use ‘many-worlds’ terminology even if the theory does not specify the worlds in the formalism; this is defended by means of an extensive analogy with the concept of an ‘instant’ or moment of time in relativity, with the lack of a preferred foliation of spacetime being compared with the lack of a preferred basis in quantum theory. Implications for identity of worlds over time, and for relativistic quantum mechanics, are discussed. 相似文献
55.
New county records are reported for Hypsiglena torquata and Rhinocheilus lecontci, and additional distribution records are presented for Sonora semiannulata in southwestern Idaho. These three species are more abundant than indicated by previous records. 相似文献
56.
K. Blum J. D. Eubanks J. E. Wallace H. A. Schwertner 《Cellular and molecular life sciences : CMLS》1976,32(4):493-495
Summary An ethanol-inhalation technique was used to determine a potential relationship between dopamine and central nervous effects produced by alcohol. Bothl-DOPA and intracranially injected dopamine resulted in attenuation of ethanol-induced withdrawal convulsion scores, whereas, haloperidol, a known dopaminergic blocker was found to significantly increase convulsion scores.We thankB. Wiggins, S. Elston andRaul Marin for technical help. The work was supported gy NIH, Air Force Office of Scientific Research and Pharmaceutical Manufacturers Association Grants. Dr.Blum is also a recipient of the Career Teacher Award, Grant No. 1-T01-D100290-01. 相似文献
57.
58.
Mutant GABA(A) receptor gamma2-subunit in childhood absence epilepsy and febrile seizures 总被引:30,自引:0,他引:30
Wallace RH Marini C Petrou S Harkin LA Bowser DN Panchal RG Williams DA Sutherland GR Mulley JC Scheffer IE Berkovic SF 《Nature genetics》2001,28(1):49-52
Epilepsies affect at least 2% of the population at some time in life, and many forms have genetic determinants. We have found a mutation in a gene encoding a GABA(A) receptor subunit in a large family with epilepsy. The two main phenotypes were childhood absence epilepsy (CAE) and febrile seizures (FS). There is a recognized genetic relationship between FS and CAE, yet the two syndromes have different ages of onset, and the physiology of absences and convulsions is distinct. This suggests the mutation has age-dependent effects on different neuronal networks that influence the expression of these clinically distinct, but genetically related, epilepsy phenotypes. We found that the mutation in GABRG2 (encoding the gamma2-subunit) abolished in vitro sensitivity to diazepam, raising the possibility that endozepines do in fact exist and have a physiological role in preventing seizures. 相似文献
59.
Integrated transcriptional profiling and linkage analysis for identification of genes underlying disease 总被引:22,自引:0,他引:22
Hubner N Wallace CA Zimdahl H Petretto E Schulz H Maciver F Mueller M Hummel O Monti J Zidek V Musilova A Kren V Causton H Game L Born G Schmidt S Müller A Cook SA Kurtz TW Whittaker J Pravenec M Aitman TJ 《Nature genetics》2005,37(3):243-253
Integration of genome-wide expression profiling with linkage analysis is a new approach to identifying genes underlying complex traits. We applied this approach to the regulation of gene expression in the BXH/HXB panel of rat recombinant inbred strains, one of the largest available rodent recombinant inbred panels and a leading resource for genetic analysis of the highly prevalent metabolic syndrome. In two tissues important to the pathogenesis of the metabolic syndrome, we mapped cis- and trans-regulatory control elements for expression of thousands of genes across the genome. Many of the most highly linked expression quantitative trait loci are regulated in cis, are inherited essentially as monogenic traits and are good candidate genes for previously mapped physiological quantitative trait loci in the rat. By comparative mapping we generated a data set of 73 candidate genes for hypertension that merit testing in human populations. Mining of this publicly available data set is expected to lead to new insights into the genes and regulatory pathways underlying the extensive range of metabolic and cardiovascular disease phenotypes that segregate in these recombinant inbred strains. 相似文献
60.
Expression of human immune interferon cDNA in E. coli and monkey cells 总被引:118,自引:0,他引:118
P W Gray D W Leung D Pennica E Yelverton R Najarian C C Simonsen R Derynck P J Sherwood D M Wallace S L Berger A D Levinson D V Goeddel 《Nature》1982,295(5849):503-508