全文获取类型
收费全文 | 227篇 |
免费 | 32篇 |
出版年
2022年 | 3篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 6篇 |
2014年 | 13篇 |
2013年 | 12篇 |
2012年 | 23篇 |
2011年 | 15篇 |
2010年 | 8篇 |
2009年 | 5篇 |
2008年 | 12篇 |
2007年 | 13篇 |
2006年 | 7篇 |
2005年 | 10篇 |
2004年 | 8篇 |
2003年 | 11篇 |
2002年 | 11篇 |
2001年 | 5篇 |
2000年 | 6篇 |
1999年 | 3篇 |
1998年 | 3篇 |
1996年 | 5篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1983年 | 2篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1977年 | 3篇 |
1972年 | 1篇 |
1971年 | 3篇 |
1970年 | 1篇 |
1968年 | 2篇 |
1967年 | 1篇 |
1966年 | 2篇 |
1965年 | 1篇 |
1963年 | 1篇 |
1962年 | 1篇 |
1959年 | 1篇 |
1937年 | 1篇 |
排序方式: 共有259条查询结果,搜索用时 15 毫秒
31.
S Hofstetter C Denter R Winter LM McMullen MG Gänzle 《Journal of microbiological methods》2012,91(1):93-100
A method for measuring the fluidity of inner membranes of populations of endospores of Clostridium spp. with a fluorescent dye was developed. Cells of Clostridium beijerinckii ATCC 8260 and Clostridium sporogenes ATCC 7955 were allowed to sporulate in the presence of 6-dodecanoyl-2-dimethylaminonaphthalene (LAURDAN) on a soil-based media. Labeling of endospores with LAURDAN did not affect endospore viability. Removal of the outer membranes of endospores was done using a chemical treatment and confirmed using transmission electron microscopy (TEM). Two-photon confocal laser scanning microscopy (CLSM), and generalized polarization (GP) measurements were used to assess fluorescence of endospores. Lipid composition analysis of cells and endospores was done to determine whether differences in GP values are attributable to differences in membrane composition. Removal of the outer membranes of endospores did not significantly impact GP values. Decoated, labeled endospores of C. sporogenes ATCC 7955 and C. beijerinckii ATCC 8260 exhibited GP values of 0.77±0.031 and 0.74±0.027 respectively. Differences in ratios of fatty acids between cells and endospores are unlikely to be responsible for high GP values observed in endospores. These GP values indicate high levels of lipid order and the exclusion of water from within inner membranes of endospores. 相似文献
32.
Genetic architecture of maize kernel composition in the nested association mapping and inbred association panels 总被引:4,自引:0,他引:4
Cook JP McMullen MD Holland JB Tian F Bradbury P Ross-Ibarra J Buckler ES Flint-Garcia SA 《Plant physiology》2012,158(2):824-834
The maize (Zea mays) kernel plays a critical role in feeding humans and livestock around the world and in a wide array of industrial applications. An understanding of the regulation of kernel starch, protein, and oil is needed in order to manipulate composition to meet future needs. We conducted joint-linkage quantitative trait locus mapping and genome-wide association studies (GWAS) for kernel starch, protein, and oil in the maize nested association mapping population, composed of 25 recombinant inbred line families derived from diverse inbred lines. Joint-linkage mapping revealed that the genetic architecture of kernel composition traits is controlled by 21-26 quantitative trait loci. Numerous GWAS associations were detected, including several oil and starch associations in acyl-CoA:diacylglycerol acyltransferase1-2, a gene that regulates oil composition and quantity. Results from nested association mapping were verified in a 282 inbred association panel using both GWAS and candidate gene association approaches. We identified many beneficial alleles that will be useful for improving kernel starch, protein, and oil content. 相似文献
33.
Lin EQ Irvine JC Cao AH Alexander AE Love JE Patel R McMullen JR Kaye DM Kemp-Harper BK Ritchie RH 《PloS one》2012,7(4):e34892
Background
New therapeutic targets for cardiac hypertrophy, an independent risk factor for heart failure and death, are essential. HNO is a novel redox sibling of NO• attracting considerable attention for the treatment of cardiovascular disorders, eliciting cGMP-dependent vasodilatation yet cGMP-independent positive inotropy. The impact of HNO on cardiac hypertrophy (which is negatively regulated by cGMP) however has not been investigated.Methods
Neonatal rat cardiomyocytes were incubated with angiotensin II (Ang II) in the presence and absence of the HNO donor Angeli''s salt (sodium trioxodinitrate) or B-type natriuretic peptide, BNP (all 1 µmol/L). Hypertrophic responses and its triggers, as well as cGMP signaling, were determined.Results
We now demonstrate that Angeli''s salt inhibits Ang II-induced hypertrophic responses in cardiomyocytes, including increases in cardiomyocyte size, de novo protein synthesis and β-myosin heavy chain expression. Angeli''s salt also suppresses Ang II induction of key triggers of the cardiomyocyte hypertrophic response, including NADPH oxidase (on both Nox2 expression and superoxide generation), as well as p38 mitogen-activated protein kinase (p38MAPK). The antihypertrophic, superoxide-suppressing and cGMP-elevating effects of Angeli''s salt were mimicked by BNP. We also demonstrate that the effects of Angeli''s salt are specifically mediated by HNO (with no role for NO• or nitrite), with subsequent activation of cardiomyocyte soluble guanylyl cyclase (sGC) and cGMP signaling (on both cGMP-dependent protein kinase, cGK-I and phosphorylation of vasodilator-stimulated phosphoprotein, VASP).Conclusions
Our results demonstrate that HNO prevents cardiomyocyte hypertrophy, and that cGMP-dependent NADPH oxidase suppression contributes to these antihypertrophic actions. HNO donors may thus represent innovative pharmacotherapy for cardiac hypertrophy. 相似文献34.
35.
Larvae of the gall fly, Eurosta solidaginis, use the cold hardiness strategy of freeze tolerance as well as entry into a hypometabolic state (diapause) to survive the winter. Cold hardiness strategies have been extensively explored in this species, but the metabolic features of winter hypometabolism have received little attention. A primary consumer of energy in cells is the ATP-dependent sodium-potassium ion pump (Na(+)K(+)-ATPase) so inhibitory controls over transmembrane ion movements could contribute substantially to energy savings over the winter months. Na(+)K(+)-ATPase activity was quantified in larvae sampled between October and April. Activity was high in October (0.56+/-0.13nmol/min/mg) but fell by 85% in November, remained low through midwinter, and then increased strongly in April. To determine whether the seasonal change in Na(+)K(+)-ATPase activity was linked with posttranslational modification of the enzyme, extracts from 15 degrees C-acclimated larvae were incubated under conditions that stimulated protein kinases A, G, or C. The action of all three kinases suppressed Na(+)K(+)-ATPase activity to levels just 3-8% of control values whereas the opposite treatment with alkaline phosphatase had no effect. Hence, the seasonal suppression of Na(+)K(+)-ATPase activity may be linked to enzyme phosphorylation. Furthermore, acute cold (3 degrees C) or hypoxia exposures of 15 degrees C-acclimated larvae did not alter enzyme activity, and freezing at -16 degrees C increased activity, so environmental factors do not appear to directly influence enzyme activity. Rather, it appears that winter suppression of ion motive ATPase activity may be part of a program of winter metabolic suppression. 相似文献
36.
37.
38.
R. Ming J. L. Brewbaker R. C. Pratt T. A. Musket M. D. McMullen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(1-2):271-275
The objective of this study was to determine the genetic basis of resistance to maize mosaic virus (MMV). Molecular markers
were used to map resistance loci to MMV in a set of 91 maize (Zea mays L.) recombinant inbred lines (RILs), derived from the cross between Hi31 (a B68 conversion resistant to MMV) and Kil4 (a
Thai inbred susceptible to MMV). The RILs were evaluated for MMV resistance in disease nurseries in Hawaii in the winter of
1993 and the summer of 1994. Twenty-eight highly susceptible RILs were chosen for gene mapping using the pooled-sampling approach.
Initial evidence from the pooled DNA indicated that restriction fragment length polymorphism (RFLP) probes on chromosome 3
near the centromere were biased to the susceptible parent allele. Analysis of 91 RILs at 103 RFLP loci confirmed the presence
of a major MMV resistance gene on chromosome 3. The resistant allele at this locus, previously named Mv1, is present in the resistant parent Hi31 and traces back to the Argentine parent used in conferring common rust resistance
to B68. We conclude that resistance to MMV in B68 and Caribbean flints involves a major gene mv1 on chromosome 3 located between RFLP markers umc102 and php20508.
Received: 12 June 1996 / Accepted: 5 July 1996 相似文献
39.
40.
Francisco H Andrade Anita P Merriam Wei Guo Georgiana Cheng Colleen A McMullen Katrin Hayess Peter F M van der ven John D Porter 《Journal of applied physiology》2003,95(2):692-699
The M lines are structural landmarks in striated muscles, necessary for sarcomeric stability and as anchoring sites for the M isoform of creatine kinase (CK-M). These structures, especially prominent in fast skeletal muscles, are missing in rodent extraocular muscle, a particularly fast and active muscle group. In this study, we tested the hypotheses that 1). myomesin and M protein (cytoskeletal components of the M lines) and CK-M are downregulated in mouse extraocular muscle compared with the leg muscles, gastrocnemius and soleus; and 2). the expression of other cytosolic and mitochondrial CK isoforms is correspondingly increased. As expected, mouse extraocular muscles expressed lower levels of myomesin, M protein, and CK-M mRNA than the leg muscles. Immunocytochemically, myomesin and M protein were not detected in the banding pattern typically seen in other skeletal muscles. Surprisingly, message abundance for the other known CK isoforms was also lower in the extraocular muscles. Moreover, total CK activity was significantly decreased compared with that in the leg muscles. Based on these data, we reject our second hypothesis and propose that other energy-buffering systems may be more important in the extraocular muscles. The downregulation of major structural and metabolic elements and relative overexpression of two adenylate kinase isoforms suggest that the extraocular muscle group copes with its functional requirements by using strategies not seen in typical skeletal muscles. 相似文献