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941.
Melanie Smee Wesley Smyth Mark Tunmore Richard ffrench-Constant Dave Hodgson 《Journal of Insect Conservation》2011,15(1-2):153-163
1. The marsh fritillary Euphydryas aurinia is one of our most endangered butterflies, and the only to be protected under European legislation as well as British. It persists in fragile subpopulations threatened by habitat fragmentation and degradation. 2. A combination of swaling and cattle grazing are accepted to be best practice for managing wet, unimproved grasslands??the favoured habitat for E. aurinia in Cornwall. These two well-endorsed methods of management were used to increase and improve the quality of habitat for E. aurinia over a 5 years period, 2004?C2008, at a stronghold network of habitat patches in mid Cornwall, south-west England. 3. Analyses of adult and larval densities over 5 years in fifty-four transects across nine sites found E. aurinia to favour habitat patches with higher densities of the larval food plant (Devil??s-bit scabious Succisa pratensis), higher sward height in autumn, and intermediate optimum levels of stock grazing. 4. Main findings indicated most sites experienced significant declines in numbers. Unfavourable weather in the last 2 years of monitoring was likely to have had a significant impact on the response of individual subpopulations to habitat management though poor recovery rates may also reflect a time-lag in colonisation events after habitat improvement has occurred. 5. Habitat management produced an improvement, albeit an inconsistent improvement in habitat variables across patches??S. pratensis shows a clear recovery at some sites. Autumn sward height increased significantly at one site, and a quadratic relationship between stock grazing and important habitat variables has been found which will aid further improvement over all sites for the long term persistence of E. aurinia. 相似文献
942.
Bir SC Pattillo CB Pardue S Kolluru GK Docherty J Goyette D Dvorsky P Kevil CG 《American journal of physiology. Heart and circulatory physiology》2012,303(2):H178-H188
Nitric oxide (NO) is a potential regulator of ischemic vascular remodeling, and as such therapies augmenting its bioavailability may be useful for the treatment of ischemic tissue diseases. Here we examine the effect of administering the NO prodrug sodium nitrite on arteriogenesis activity during established tissue ischemia. Chronic hindlimb ischemia was induced by permanent unilateral femoral artery and vein ligation. Five days postligation; animals were randomized to control PBS or sodium nitrite (165 μg/kg) therapy twice daily. In situ vascular remodeling was measured longitudinally using SPY angiography and Microfil vascular casting. Delayed sodium nitrite therapy rapidly increased ischemic limb arterial vessel diameter and branching in a NO-dependent manner. SPY imaging angiography over time showed that nitrite therapy enhanced ischemic gracillis collateral vessel formation from the profunda femoris to the saphenous artery. Immunofluorescent staining of smooth muscle cell actin also confirmed that sodium nitrite therapy increased arteriogenesis in a NO-dependent manner. The NO prodrug sodium nitrite significantly increases arteriogenesis and reperfusion of established severe chronic tissue ischemia. 相似文献
943.
Sprague J Clements D Conlin T Edwards P Frazer K Schaper K Segerdell E Song P Sprunger B Westerfield M 《Nucleic acids research》2003,31(1):241-243
The Zebrafish Information Network (ZFIN) is a web based community resource that serves as a centralized location for the curation and integration of zebrafish genetic, genomic and developmental data. ZFIN is publicly accessible at http://zfin.org. ZFIN provides an integrated representation of mutants, genes, genetic markers, mapping panels, publications and community contact data. Recent enhancements to ZFIN include: (i) an anatomical dictionary that provides a controlled vocabulary of anatomical terms, grouped by developmental stages, that may be used to annotate and query gene expression data; (ii) gene expression data; (iii) expanded support for genome sequence; (iv) gene annotation using the standardized vocabulary of Gene Ontology (GO) terms that can be used to elucidate relationships between gene products in zebrafish and other organisms; and (v) collaborations with other databases (NCBI, Sanger Institute and SWISS-PROT) to provide standardization and interconnections based on shared curation. 相似文献
944.
Production of tumor necrosis factor α and interferon γ in interleukin-2-treated melanoma patients: Correlation with clinical toxicity 总被引:1,自引:0,他引:1
James S. Economou Mary Hoban Jeffrey D. Lee Richard Essner Stephen Swisher William McBride Dave B. Hoon Donald L. Morton 《Cancer immunology, immunotherapy : CII》1991,34(1):49-52
Summary Interleukin-2 (IL-2)-based immunotherapy regimens are accompanied by dose-limiting toxicity consisting of fever, tachycardia, chills and capillary leak syndrome. We hypothesized that the toxicity was caused by the induction and release of endogenous cytokines such as tumor necrosis factor (TNF) and interferon (IFN). We measured the serum levels of TNF and IFN in IL-2-treated melanoma patients and attempted a correlation with clinical toxicity. A total of 23 patients received either 6 × 106 IU or 12 × 106 IU Cetus IL-2/m2 by i. v. bolus daily for 5 consecutive days on weeks 1, 3 and 5. Serum TNF and IFN levels were measured by enzyme-linked immunosorbent assay. Clinical toxicity was scored each day by objective measurements of hypotension, tachycardia, fever and chills/rigors. Clinical toxicity and IFN levels correlated nicely, peaking on the 5th day of each treatment cycle. The kinetics and magnitude of TNF production, however, were not predictable and did not correlate with either IFN or toxicity. Some patients had modest increases in TNF production while others had markedly increased levels during the second and third treatment weeks. Remarkably, these high levels persisted during nontreatment weeks and after completion of therapy. This clinical study demonstrates novel kinetics for immunoreactive TNF in IL-2 cancer patients, which do not correlate well with toxicity.This work was supported by NIH Grants CA 50 780 (J. E.) and CA 29 605, CA 12 582 (D. L. M.) and the U. C. Tobacco-Related Disease Research Program RT-62 (J. E.). J. E. is the recipient of an NCI Clinical Investigator Award (KO8-01360) and is a Dorothy and Leonard Straus Scholar at UCLA 相似文献
945.
Patricia P Souza Pamela Völkel Dave Trinel Julien Vandamme Claire Rosnoblet Laurent Héliot Pierre-Olivier Angrand 《BMC cell biology》2009,10(1):41-16
Background
Histone lysine methylation plays a fundamental role in chromatin organization and marks distinct chromatin regions. In particular, trimethylation at lysine 9 of histone H3 (H3K9) and at lysine 20 of histone H4 (H4K20) governed by the histone methyltransferases SUV39H1/2 and SUV420H1/2 respectively, have emerged as a hallmark of pericentric heterochromatin. Controlled chromatin organization is crucial for gene expression regulation and genome stability. Therefore, it is essential to analyze mechanisms responsible for high order chromatin packing and in particular the interplay between enzymes involved in histone modifications, such as histone methyltransferases and proteins that recognize these epigenetic marks. 相似文献946.
Dave Gardonio 《Biochemical and biophysical research communications》2009,381(1):107-9134
A method involving the reversible chemical modification of an active site, zinc-binding cysteine residue (Cys221) for the specific removal of one of the two zinc ions in the metallo-β-lactamase IMP-1 was explored. Covalent modification of Cys221 by 5,5′-dithio-bis(2-nitrobenzoic acid) was greatly enhanced by the presence of dipicolinic acid, and subsequent removal of the modifying group was easily achieved by reduction of the disulfide bond. However, mass spectrometric analyses and an assessment of IMP-1’s catalytic competence are consistent with the maintenance of the enzyme’s binuclear status. The consequences arising from chemical modification of Cys221 are thus distinct from those reported for Cys → Ala/Ser mutants of IMP-1 and other metallo-β-lactamases, which are mononuclear. 相似文献
947.
E Balducci M Emanuelli N Raffaelli G Magni 《Bollettino della Società italiana di biologia sperimentale》1989,65(11):1059-1066
It has long been known that the major function of NAD+ is as an electron carrier in various biological oxidation-reduction systems. From many papers it is evident that NAD+ is involved as substrate in ADP-ribosylation reactions. We have focused our attention on two chromatin enzymes: NMN-adenylyltransferase that catalyzes reversible synthesis of NAD+ utilizing ATP and NMN, and poly(ADP-ribose)polymerase that covalently modifies nucleosomal proteins through poly ADP-ribosylation reactions. Here we provided evidence of these activities in a system of isolated nuclei from human placenta. The data presented in this report show that purified nuclei might be useful to study the nuclear location of these enzymes and their reciprocal interactions. 相似文献
948.
949.
In this paper we present a simple method for identifying life-history perturbations in population projection matrices that yield an accelerating population growth rate. Accelerating growth means that the dependence of the growth rate on the perturbation is convex. Convexity, when the second sensitivity of the growth rate is positive, is calculated using a new formula derived from the transfer function of the perturbed system. This formula is used to explore the relationship between stasis and growth probabilities from stage-structured population projection matrices. 相似文献
950.
Garrity GM Field D Kyrpides N Hirschman L Sansone SA Angiuoli S Cole JR Glöckner FO Kolker E Kowalchuk G Moran MA Ussery D White O 《Omics : a journal of integrative biology》2008,12(2):157-160
Increasingly, we are aware as a community of the growing need to manage the avalanche of genomic and metagenomic data, in addition to related data types like ribosomal RNA and barcode sequences, in a way that tightly integrates contextual data with traditional literature in a machine-readable way. It is for this reason that the Genomic Standards Consortium (GSC) formed in 2005. Here we suggest that we move beyond the development of standards and tackle standards compliance and improved data capture at the level of the scientific publication. We are supported in this goal by the fact that the scientific community is in the midst of a publishing revolution. This revolution is marked by a growing shift away from a traditional dichotomy between "journal articles" and "database entries" and an increasing adoption of hybrid models of collecting and disseminating scientific information. With respect to genomes and metagenomes and related data types, we feel the scientific community would be best served by the immediate launch of a central repository of short, highly structured "Genome Notes" that must be standards compliant. This could be done in the context of an existing journal, but we also suggest the more radical solution of launching a new journal. Such a journal could be designed to cater to a wide range of standards-related content types that are not currently centralized in the published literature. It could also support the demand for centralizing aspects of the "gray literature" (documents developed by institutions or communities) such as the call by the GSC for a central repository of Standard Operating Procedures describing the genomic annotation pipelines of the major sequencing centers. We argue that such an "eJournal," published under the Open Access paradigm by the GSC, could be an attractive publishing forum for a broader range of standardization initiatives within, and beyond, the GSC and thereby fill an unoccupied yet increasingly important niche within the current research landscape. 相似文献