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181.
Solid-Phase synthesis of a dendritic peptide related to a retinoblastoma protein fragment utilizing a combined boc- and fmoc-chemistry approach. 总被引:1,自引:0,他引:1
Dendritic peptides, often presented as multiple antigen peptides (MAPs), are widely used in immunological-based fields of research, although their synthesis can be extremely challenging. In this paper, a tetrameric dendritic MAP-like presentation of the retinoblastoma protein [649-654] sequence (4RB(649-654)) has been prepared using solid-phase peptide synthesis (SPPS) methods. During the synthesis of this dendritic molecule, numerous modifications to the synthetic protocols were examined. These modifications included the introduction of a combination Boc- and Fmoc-chemistry approach and also the use of 1,8-diazabicyclo[5.4.0]-undec-7-ene as a Fmoc-deprotection agent. The use in combination of Boc- and Fmoc-based synthetic strategies resulted in the production of the desired peptide molecule, 4RB(649-654), in high purity and acceptable yields following purification by reversed phase HPLC. 相似文献
182.
Review of the 2012 Epizootic Hemorrhagic Disease Outbreak in Domestic Ruminants in the United States
An unusually large number of cases of Epizootic hemorrhagic disease (EHD) were observed in United States cattle and white-tailed deer in the summer and fall of 2012. USDA APHIS Veterinary Services area offices were asked to report on foreign animal disease investigations and state diagnostic laboratory submissions which resulted in a diagnosis of EHD based on positive PCR results. EHD was reported in the following species: cattle (129 herds), captive white-tailed deer (65 herds), bison (8 herds), yak (6 herds), elk (1 herd), and sheep (1 flock). A majority of the cases in cattle and bison were found in Nebraska, South Dakota, and Iowa. The majority of cases in captive white-tailed deer were found in Ohio, Iowa, Michigan, and Missouri. The most common clinical sign observed in the cattle and bison herds was oral lesions. The major observation in captive white-tailed deer herds was death. Average within-herd morbidity was 7% in cattle and bison herds, and 46% in captive white-tailed deer herds. The average within-herd mortality in captive white-tailed deer herds was 42%. 相似文献
183.
Sperry Jinelle H. O’Hearn Dylan Drake Donald R. Hruska Amy M. Case Samuel B. Vizentin-Bugoni Jeferson Arnett Clint Chambers Tim Tarwater Corey E. 《Biological invasions》2021,23(6):1819-1835
Biological Invasions - For alien invasive plant species dependent on frugivores for seed dispersal, traits that influence consumption can be important determinants of invasion and spread. However,... 相似文献
184.
Rudy Ciayadi Geoffrey F. Kelso Mahesh K. Potdar Simon J. Harris Kelly L. Walton Craig A. Harrison Milton T.W. Hearn 《Bioorganic & medicinal chemistry》2013,21(21):6496-6500
We have investigated the binding characteristics of a potent member of the bis-ortho-substituted five-membered nitrogen heterocycle class of ALK-5 kinase inhibitors with lysates of cultured HEK-293 cells to identify protein binding partners of potential biological significance. An affinity chromatographic resin containing an immobilized ALK-5 kinase inhibitor, 2-phenyl-4-[3-(pyridin-2-yl)-1H-pyrazol-4-yl]pyridine, was used to capture specific proteins from the cell lysate. The soluble inhibitor was then used to specifically elute the proteins which selectively bound to the pharmacophore ligand structure. Application of 2-D SDS–PAGE analysis with positive and negative controls demonstrated the inhibitor bound several different proteins via selective molecular recognition processes. The structural features of the specifically eluted proteins were identified by peptide mass fingerprinting (PMF) methods and included proteins with structural, metabolic and chaperone functions. Furthermore, these PMF results identified the therapeutic target in various cancer treatment studies, HSP-70, as a potential high-affinity binding partner. These observations warrant examination of bis-ortho-substituted five-membered nitrogen heterocycles as dual ALK-5/HSP-70 inhibitors for anti-cancer drug development. 相似文献
185.
186.
Hearn DJ 《American journal of botany》2009,96(11):1941-1956
The architecture of flowering plants is astonishingly diverse. To understand evolutionary patterns and processes that account for this diversity, I investigated developmental anatomy of storage roots and stems of 58 species in the genus Adenia (Passifloraceae) using an explicit phylogenetic context. Because expanded storage roots and stem succulence evolved multiple times in Adenia, patterns of transition between succulent and nonsucculent forms were analyzed using a comparative test that accommodates phylogenetic uncertainty. I tested the innervation hypothesis, wherein I expected the evolution of vascular strands to be correlated with evolutionary increases in water storage tissue if evolution of vascular strands facilitates transport through water and starch storage structures. Not only is evolution of vascular strands in stems statistically coupled with evolutionary increases in parenchyma storage tissue, most lineages that evolved expanded storage roots also evolved vascular strands in these roots in parallel to succulent stems. I proposed that vascular strands and closely associated storage parenchyma found in both roots and shoots of Adenia comprise a homologous unit. A switch-like evolutionary mechanism that alters the spatial expression of this unit between roots and shoots can account, in large part, for transitions between markedly different habits such as storage-rooted herbs and succulent-stemmed shrubs. 相似文献
187.
Matthieu Guillemain Richard Hearn Roy King Michel Gauthier-Clerc Géraldine Simon Alain Caizergues 《Journal of Ornithology》2009,150(3):685-689
The “body size hypothesis” predicts that if individuals of a population migrate different distances from the breeding to the
wintering grounds, the distance should be related to the differential ability to cope with adverse conditions, with larger
individuals wintering further north. Data collected over a 40-year period in Essex, UK and the Camargue, southern France,
revealed that the average body mass of Teal ringed in Essex during these years was actually not greater than that of Teal
ringed in the Camargue. A higher proportion of males were included in the UK ringing catch than in the French catch, but we
found no support for the body size hypothesis to explain such differential migration of the sexes. 相似文献
188.
Applications of novel affinity cassette methods: use of peptide fusion handles for the purification of recombinant proteins. 总被引:5,自引:0,他引:5
In this article, recent progress related to the use of different types of polypeptide fusion handles or 'tags' for the purification of recombinant proteins are critically discussed. In addition, novel aspects of the molecular cassette concept are elaborated, together with areas of potential application of these fundamental principles in molecular recognition. As evident from this review, the use of these concepts provides a powerful strategy for the high throughput isolation and purification of recombinant proteins and their derived domains, generated from functional genomic or zeomic studies, as part of the bioprocess technology leading to their commercial development, and in the study of molecular recognition phenomena per se. In addition, similar concepts can be exploited for high sensitivity analysis and detection, for the characterisation of protein bait/prey interactions at the molecular level, and for the immobilisation and directed orientation of proteins for use as biocatalysts/biosensors. 相似文献
189.
Deinococcus radiodurans (Drad), a bacterium with an extraordinary capacity to tolerate high levels of ionizing radiation, produces only a manganese-containing superoxide dismutase (MnSOD). As MnSOD has been shown to remove superoxide radical with varying efficiency depending upon its cellular origin, a comparison of the Drad MnSOD efficiency with that of both human and Escherichia coli MnSODs was undertaken. Pulse radiolysis studies demonstrate that, under identical ratios of enzyme to superoxide radical, the dismutation efficiencies scaled as Drad MnSOD > E. coli MnSOD > human MnSOD. Further, Drad MnSOD is most effective at high superoxide fluxes found under conditions of high radioactivity. A mechanism is postulated to account for the differences in the activities of the MnSODs that considers the release of peroxide as not always an optimal process. 相似文献
190.
The secondary structures of proteins (alpha-helical, beta-sheet, beta-turn, and random coil) in the solid state and when bound to polymer beads, containing immobilized phenyl and butyl ligands such as those as commonly employed in hydrophobic interaction chromatography, have been investigated using FTIR-ATR spectroscopy and partial least squares (PLS) methods. Proteins with known structural features were used as models, including 12 proteins in the solid state and 7 proteins adsorbed onto the hydrophobic surfaces. A strong PLS correlation was achieved between predictions derived from the experimental data for 4 proteins adsorbed onto the phenyl-modified beads and reference data obtained from the X-ray crystallographic structures with r(2) values of 0.9974, 0.9864, 0.9924, and 0.9743 for alpha-helical, beta-sheet, beta-turn, and random coiled structures, respectively. On the other hand, proteins adsorbed onto the butyl sorbent underwent greater secondary structural changes compared to the phenyl sorbent as evidenced from the poorer PLS r(2) values (r(2) are 0.9658, 0.9106, 0.9571, and 0.9340). The results thus indicate that the secondary structures for these proteins were more affected by the butyl sorbent, whereas the secondary structure remains relatively unchanged for the proteins adsorbed onto the phenyl sorbent. This study has important ramifications for understanding the nature of protein secondary structural changes following adsorption onto hydrophobic sorbent surfaces. This knowledge could also enable the development of useful protocols for enhancing the chromatographic purification of proteins in their native bioactive states. (c) 2008 Wiley Periodicals, Inc. Biopolymers 89: 895-905, 2008.This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com. 相似文献