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81.
82.
Darlina Md. Naim Sandra Telfer Stephanie Sanderson Stephen J. Kemp Phillip C. Watts 《Conservation Genetics》2011,12(4):971-979
Mating behaviour is an important component of species’ life histories. Knowledge of natural patterns of mating can lead also
to more effective management strategies for populations of conservation concern. Despite a high conservation profile many
aspects of the biology of the common dormouse (Muscardinus avellanarius) remain unknown, potentially limiting present conservation efforts. We determine the mating behaviour of M. avellanarius at two woodland sites in the UK: (1) Bontuchel (a natural population in Wales) and (2) Wych (a population in England that
was established by reintroducing captive-bred animals) by genotyping mothers and litters at a panel of 10 microsatellite loci.
Adult female body weight positively correlates with litter size and no apparent reproductive skew was evident. We found that
multiple mating by female dormice is prevalent at both sites, with litters containing three or more offspring sired by multiple
fathers; moreover, multiple mating is adopted by released animals even after a period of captive breeding where females are
mated singly or as a breeding pair. We also present evidence for low proportion of fathers identified in our samples that
probably related to unsampled individuals and/or larger than anticipated population sizes. This first report of mating behaviour
in M. avellanarius highlights the role of genetic studies to uncover species’ reproductive behaviours and include these data for conservation
management. 相似文献
83.
Brad Boyle Nicole Hopkins Zhenyuan Lu Juan Antonio Raygoza Garay Dmitry Mozzherin Tony Rees Naim Matasci Martha L Narro William H Piel Sheldon J Mckay Sonya Lowry Chris Freeland Robert K Peet Brian J Enquist 《BMC bioinformatics》2013,14(1):1-15
Background
The digitization of biodiversity data is leading to the widespread application of taxon names that are superfluous, ambiguous or incorrect, resulting in mismatched records and inflated species numbers. The ultimate consequences of misspelled names and bad taxonomy are erroneous scientific conclusions and faulty policy decisions. The lack of tools for correcting this ‘names problem’ has become a fundamental obstacle to integrating disparate data sources and advancing the progress of biodiversity science.Results
The TNRS, or Taxonomic Name Resolution Service, is an online application for automated and user-supervised standardization of plant scientific names. The TNRS builds upon and extends existing open-source applications for name parsing and fuzzy matching. Names are standardized against multiple reference taxonomies, including the Missouri Botanical Garden's Tropicos database. Capable of processing thousands of names in a single operation, the TNRS parses and corrects misspelled names and authorities, standardizes variant spellings, and converts nomenclatural synonyms to accepted names. Family names can be included to increase match accuracy and resolve many types of homonyms. Partial matching of higher taxa combined with extraction of annotations, accession numbers and morphospecies allows the TNRS to standardize taxonomy across a broad range of active and legacy datasets.Conclusions
We show how the TNRS can resolve many forms of taxonomic semantic heterogeneity, correct spelling errors and eliminate spurious names. As a result, the TNRS can aid the integration of disparate biological datasets. Although the TNRS was developed to aid in standardizing plant names, its underlying algorithms and design can be extended to all organisms and nomenclatural codes. The TNRS is accessible via a web interface at http://tnrs.iplantcollaborative.org/ and as a RESTful web service and application programming interface. Source code is available at https://github.com/iPlantCollaborativeOpenSource/TNRS/. 相似文献84.
85.
Ranawaka Buddhini Tanurdzic Milos Waterhouse Peter Naim Fatima 《Molecular biology reports》2020,47(12):9499-9509
Molecular Biology Reports - All flowering plants have evolved through multiple rounds of polyploidy throughout the evolutionary process. Intergenomic interactions between subgenomes in polyploid... 相似文献
86.
RNA interference (RNAi) pathways regulate self-renewal and differentiation of embryonic stem (ES) cells. Argonaute 2 (Ago2) is a vital component of RNA-induced silencing complex (RISC) and the only Ago protein with slicer activity. We generated
Ago2-deficient ES cells by conditional gene targeting. Ago2-deficient ES cells are defective in the small-RNA-mediated gene silencing and are significantly compromised in biogenesis
of mature microRNA. The self-renewal rate of Ago2-deficient ES cells is affected due to failure of silencing of Cdkn1a by ES-cell-specific microRNAs (miRNA) in the absence of Ago2. Interestingly, unlike Dicer- and Dgcr8-deficient ES cells, they differentiate to all three germ layers both in vivo and in vitro. However, early differentiation of Ago2-deficient ES cells is delayed by 2–4 days as indicated by persistence of higher levels of self-renewal/ pluripotency markers
during differentiation. Further, appearance of morphological and differentiation markers is also delayed during the differentiation.
In this study we show that Ago2 is essential for normal self-renewal and differentiation. Also, our data suggest that self-renewal and differentiation of
ES cells are regulated by both siRNA and miRNA pathways. 相似文献
87.
Hydrogen production was studied using immobilized green alga Chlorella sp. through a two-stage cyclic process where immobilized cells were first incubated in oxygenic photosynthesis followed by anaerobic incubation for H2 production in the absence of sulfur. Chlorella sp. used in this study was capable of generating H2 under immobilized state in agar. The externally added glucose enhanced H2 production rates and total produced volume while shortened the lag time required for cell adaptation prior to H2 evolution. The rate of hydrogen evolution was increased as temperature increased, and the maximum evolution rate under 30 mM glucose was 183 mL/h/L and 238 mL/h/L at 37 °C and 40 °C, respectively. In order to continue repeated cycles of H2 production, at least two days of photosynthesis stage should be allowed for cells to recover H2 production potential and cell viability before returning to H2 production stage again. 相似文献
88.
Jones K Sim L Mohan S Kumarasamy J Liu H Avery S Naim HY Quezada-Calvillo R Nichols BL Pinto BM Rose DR 《Bioorganic & medicinal chemistry》2011,19(13):3929-3934
Inhibition of intestinal α-glucosidases and pancreatic α-amylases is an approach to controlling blood glucose and serum insulin levels in individuals with Type II diabetes. The two human intestinal glucosidases are maltase-glucoamylase and sucrase-isomaltase. Each incorporates two family 31 glycoside hydrolases responsible for the final step of starch hydrolysis. Here we compare the inhibition profiles of the individual N- and C-terminal catalytic subunits of both glucosidases by clinical glucosidase inhibitors, acarbose and miglitol, and newly discovered glucosidase inhibitors from an Ayurvedic remedy used for the treatment of Type II diabetes. We show that features of the compounds introduce selectivity towards the subunits. Together with structural data, the results enhance the understanding of the role of each catalytic subunit in starch digestion, helping to guide the development of new compounds with subunit specific antidiabetic activity. The results may also have relevance to other metabolic diseases such as obesity and cardiovascular disease. 相似文献
89.
Khan NA 《Indian journal of biochemistry & biophysics》2007,44(5):344-349
A number of studies have recently addressed the correlationship between diabetic pregnancy/macrosomia and differentiation of T-cells into Th1 and Th2 subsets. Diabetic pregnancy has been found to be associated with a decreased Th1 phenotype and IL-4 mRNA expression. In macrosomic offspring, high expression of IL-2 and IFN-gamma mRNA, but not of Th2 cytokines is observed, indicating that the Th1 phenotype is upregulated during macrosomia. T-cells of gestational diabetic rats and their macrosomic offspring seem to present a defect in signal transduction. Indeed, the recruitment of free intracellular calcium concentrations from intracellular pool in T-cells of these animals is altered. The phenotype of regulatory T-cells (T-Reg) is upregulated in diabetic pregnancy and their infants. T-cells in diabetic pregnancy and macrosomic obese offspring are in vivo activated. Adipokines and peroxisome proliferator-activated receptor-alpha (PPARalpha) also seem to modulate the pro-inflammatory cytokines in these pathologies. Hence, activation of the immune system might be considered as one of the regulatory pathways including metabolic abnormalities in these two pathologies. 相似文献
90.