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11.
Brian K. Sullivan 《西北部美国博物学家》2011,46(2)
Advertisement call variation and male mating success was investigated in a population of the Arizona tree frog, Hyla wrightorum , from central Arizona. Dominant frequency of advertisement calls was significantly correlated (negatively) with male snout-vent length. Males found mating were not significantly larger than nonmating males, nor was there a significant correlation between sizes of males and females found in amplexus. These results are discussed in relation to Renaud's (1977) work with H. wrightorum and in light of recent work with anurans in general. 相似文献
12.
H Zhang C Peng Y Hu H Li Z Sheng Y Chen C Sullivan J Cerny L Hutchinson A Higgins P Miron X Zhang MA Brehm D Li MR Green S Li 《Nature genetics》2012,44(8):861-871
A therapeutic strategy for treating cancer is to target and eradicate cancer stem cells (CSCs) without harming their normal stem cell counterparts. The success of this approach relies on the identification of molecular pathways that selectively regulate CSC function. Using BCR-ABL-induced chronic myeloid leukemia (CML) as a disease model for CSCs, we show that BCR-ABL downregulates the Blk gene (encoding B-lymphoid kinase) through c-Myc in leukemic stem cells (LSCs) in CML mice and that Blk functions as a tumor suppressor in LSCs but does not affect normal hematopoietic stem cells (HSCs) or hematopoiesis. Blk suppresses LSC function through a pathway involving an upstream regulator, Pax5, and a downstream effector, p27. Inhibition of this Blk pathway accelerates CML development, whereas increased activity of the Blk pathway delays CML development. Blk also suppresses the proliferation of human CML stem cells. Our results show the feasibility of selectively targeting LSCs, an approach that should be applicable to other cancers. 相似文献
13.
Alain Debec William Sullivan Monica Bettencourt-Dias 《Cellular and molecular life sciences : CMLS》2010,67(13):2173-2194
Centrioles are cylinders made of nine microtubule (MT) triplets present in many eukaryotes. Early studies, where centrosomes
were seen at the poles of the mitotic spindle led to their coining as “the organ for cell division”. However, a variety of subsequent observational and functional studies showed that centrosomes might not always be essential
for mitosis. Here we review the arguments in this debate. We describe the centriole structure and its distribution in the
eukaryotic tree of life and clarify its role in the organization of the centrosome and cilia, with an historical perspective.
An important aspect of the debate addressed in this review is how centrioles are inherited and the role of the spindle in
this process. In particular, germline inheritance of centrosomes, such as their de novo formation in parthenogenetic species,
poses many interesting questions. We finish by discussing the most likely functions of centrioles and laying out new research
avenues. 相似文献
14.
Bredemeyer AL Sharma GG Huang CY Helmink BA Walker LM Khor KC Nuskey B Sullivan KE Pandita TK Bassing CH Sleckman BP 《Nature》2006,442(7101):466-470
The ATM (ataxia-telangiectasia mutated) protein kinase mediates early cellular responses to DNA double-strand breaks (DSBs) generated during metabolic processes or by DNA-damaging agents. ATM deficiency leads to ataxia-telangiectasia, a disease marked by lymphopenia, genomic instability and an increased predisposition to lymphoid malignancies with chromosomal translocations involving lymphocyte antigen receptor loci. ATM activates cell-cycle checkpoints and can induce apoptosis in response to DNA DSBs. However, defects in these pathways of the DNA damage response cannot fully account for the phenotypes of ATM deficiency. Here, we show that ATM also functions directly in the repair of chromosomal DNA DSBs by maintaining DNA ends in repair complexes generated during lymphocyte antigen receptor gene assembly. When coupled with the cell-cycle checkpoint and pro-apoptotic activities of ATM, these findings provide a molecular explanation for the increase in lymphoid tumours with translocations involving antigen receptor loci associated with ataxia-telangiectasia. 相似文献
15.
Howell DA Sullivan M Nugent PE Ellis RS Conley AJ Le Borgne D Carlberg RG Guy J Balam D Basa S Fouchez D Hook IM Hsiao EY Neill JD Pain R Perrett KM Pritchet CJ 《Nature》2006,443(7109):308-311
The accelerating expansion of the Universe, and the need for dark energy, were inferred from observations of type Ia supernovae. There is a consensus that type Ia supernovae are thermonuclear explosions that destroy carbon-oxygen white dwarf stars that have accreted matter from a companion star, although the nature of this companion remains uncertain. These supernovae are thought to be reliable distance indicators because they have a standard amount of fuel and a uniform trigger: they are predicted to explode when the mass of the white dwarf nears the Chandrasekhar mass of 1.4 solar masses (M(o)). Here we show that the high-redshift supernova SNLS-03D3bb has an exceptionally high luminosity and low kinetic energy that both imply a super-Chandrasekhar-mass progenitor. Super-Chandrasekhar-mass supernovae should occur preferentially in a young stellar population, so this may provide an explanation for the observed trend that overluminous type Ia supernovae occur only in 'young' environments. As this supernova does not obey the relations that allow type Ia supernovae to be calibrated as standard candles, and as no counterparts have been found at low redshift, future cosmology studies will have to consider possible contamination from such events. 相似文献
16.
Tomlinson IP Webb E Carvajal-Carmona L Broderick P Howarth K Pittman AM Spain S Lubbe S Walther A Sullivan K Jaeger E Fielding S Rowan A Vijayakrishnan J Domingo E Chandler I Kemp Z Qureshi M Farrington SM Tenesa A Prendergast JG Barnetson RA Penegar S Barclay E Wood W Martin L Gorman M Thomas H Peto J Bishop DT Gray R Maher ER Lucassen A Kerr D Evans DG;CORGI Consortium Schafmayer C Buch S Völzke H Hampe J Schreiber S John U Koessler T Pharoah P van Wezel T Morreau H Wijnen JT Hopper JL 《Nature genetics》2008,40(5):623-630
To identify colorectal cancer (CRC) susceptibility alleles, we conducted a genome-wide association study. In phase 1, we genotyped 550,163 tagSNPs in 940 familial colorectal tumor cases (627 CRC, 313 high-risk adenoma) and 965 controls. In phase 2, we genotyped 42,708 selected SNPs in 2,873 CRC cases and 2,871 controls. In phase 3, we evaluated 11 SNPs showing association at P < 10(-4) in a joint analysis of phases 1 and 2 in 4,287 CRC cases and 3,743 controls. Two SNPs were taken forward to phase 4 genotyping (10,731 CRC cases and 10,961 controls from eight centers). In addition to the previously reported 8q24, 15q13 and 18q21 CRC risk loci, we identified two previously unreported associations: rs10795668, located at 10p14 (P = 2.5 x 10(-13) overall; P = 6.9 x 10(-12) replication), and rs16892766, at 8q23.3 (P = 3.3 x 10(-18) overall; P = 9.6 x 10(-17) replication), which tags a plausible causative gene, EIF3H. These data provide further evidence for the 'common-disease common-variant' model of CRC predisposition. 相似文献
17.
Stress or administration of ACTH to pregnant mice gave rise to much higher plasma corticosterone levels in the second half of pregnancy than in the first half, suggesting that there may be increased adrenal sensitivity to ACTH or decreased metabolism of corticosterone during the second half of pregnancy. 相似文献
18.
Haploinsufficiency of CBFA2 causes familial thrombocytopenia with propensity to develop acute myelogenous leukaemia. 总被引:21,自引:0,他引:21
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