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141.
Granzyme B‐expressing neutrophils correlate with bacterial load in granulomas from Mycobacterium tuberculosis‐infected cynomolgus macaques
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Joshua T. Mattila Pauline Maiello Tao Sun Laura E. Via JoAnne L. Flynn 《Cellular microbiology》2015,17(8):1085-1097
The role of neutrophils in tuberculosis (TB), and whether neutrophils express granzyme B (grzB), a pro‐apoptotic enzyme associated with cytotoxic T cells, is controversial. We examined neutrophils in peripheral blood (PB) and lung granulomas of Mycobacterium tuberculosis‐infected cynomolgus macaques and humans to determine whether mycobacterial products or pro‐inflammatory factors induce neutrophil grzB expression. We found large numbers of grzB‐expressing neutrophils in macaque and human granulomas and these cells contained more grzB+ granules than T cells. Higher neutrophil, but not T cell, grzB expression correlated with increased bacterial load. Although unstimulated PB neutrophils lacked grzB expression, grzB expression increased upon exposure to M. tuberculosis bacilli, M. tuberculosis culture filtrate protein or lipopolysaccharide from Escherichia coli. Perforin is required for granzyme‐mediated cytotoxicity by T cells, but was not observed in PB or granuloma neutrophils. Nonetheless, stimulated PB neutrophils secreted grzB as determined by enzyme‐linked immunospot assays. Purified grzB was not bactericidal or bacteriostatic, suggesting secreted neutrophil grzB acts on extracellular targets, potentially enhancing neutrophil migration through extracellular matrix and regulating apoptosis or activation in other cell types. These data indicate mycobacterial products and the pro‐inflammatory environment of granulomas up‐regulates neutrophil grzB expression and suggests a previously unappreciated aspect of neutrophil biology in TB. 相似文献
142.
Judith Burstin Pauline Salloignon Marianne Chabert-Martinello Jean-Bernard Magnin-Robert Mathieu Siol Fran?oise Jacquin Aurélie Chauveau Caroline Pont Grégoire Aubert Catherine Delaitre Caroline Truntzer Gérard Duc 《BMC genomics》2015,16(1)
Background
Pea (Pisum sativum L.), a major pulse crop grown for its protein-rich seeds, is an important component of agroecological cropping systems in diverse regions of the world. New breeding challenges imposed by global climate change and new regulations urge pea breeders to undertake more efficient methods of selection and better take advantage of the large genetic diversity present in the Pisum sativum genepool. Diversity studies conducted so far in pea used Simple Sequence Repeat (SSR) and Retrotransposon Based Insertion Polymorphism (RBIP) markers. Recently, SNP marker panels have been developed that will be useful for genetic diversity assessment and marker-assisted selection.Results
A collection of diverse pea accessions, including landraces and cultivars of garden, field or fodder peas as well as wild peas was characterised at the molecular level using newly developed SNP markers, as well as SSR markers and RBIP markers. The three types of markers were used to describe the structure of the collection and revealed different pictures of the genetic diversity among the collection. SSR showed the fastest rate of evolution and RBIP the slowest rate of evolution, pointing to their contrasted mode of evolution. SNP markers were then used to predict phenotypes -the date of flowering (BegFlo), the number of seeds per plant (Nseed) and thousand seed weight (TSW)- that were recorded for the collection. Different statistical methods were tested including the LASSO (Least Absolute Shrinkage ans Selection Operator), PLS (Partial Least Squares), SPLS (Sparse Partial Least Squares), Bayes A, Bayes B and GBLUP (Genomic Best Linear Unbiased Prediction) methods and the structure of the collection was taken into account in the prediction. Despite a limited number of 331 markers used for prediction, TSW was reliably predicted.Conclusion
The development of marker assisted selection has not reached its full potential in pea until now. This paper shows that the high-throughput SNP arrays that are being developed will most probably allow for a more efficient selection in this species.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1266-1) contains supplementary material, which is available to authorized users. 相似文献143.
Amandine Berthoud Pauline Maupu Camille Huet Antoine Poupart 《The International Journal of Life Cycle Assessment》2011,16(8):841-847
Purpose
A life cycle assessment (LCA) was conducted on winter wheat, based on real agricultural practices databases, on a sample divided into four production scenarios. The main objectives of this study are (1) to assess the environmental impact of winter wheat, using an LCA covering field practices, and the transport and storage of grain until it is sold to a miller; (2) to use the USEtox model (Rosenbaum et al. in Int J Life Cycle Assess 13:532–546, 2008) to assess the part of the total freshwater ecotoxicity impact due to pesticide use, its variability among plots, and to identify the active ingredients with the strongest impact; (3) and with the help of fungicide, insecticide, herbicide experts, to identify active ingredients to replace these high-impact pesticides and estimate the effect of such a substitution on total freshwater ecotoxicity. 相似文献144.
Charles C Hovorakova M Ahn Y Lyons DB Marangoni P Churava S Biehs B Jheon A Lesot H Balooch G Krumlauf R Viriot L Peterkova R Klein OD 《Development (Cambridge, England)》2011,138(18):4063-4073
Much of our knowledge about mammalian evolution comes from examination of dental fossils, because the highly calcified enamel that covers teeth causes them to be among the best-preserved organs. As mammals entered new ecological niches, many changes in tooth number occurred, presumably as adaptations to new diets. For example, in contrast to humans, who have two incisors in each dental quadrant, rodents only have one incisor per quadrant. The rodent incisor, because of its unusual morphogenesis and remarkable stem cell-based continuous growth, presents a quandary for evolutionary biologists, as its origin in the fossil record is difficult to trace, and the genetic regulation of incisor number remains a largely open question. Here, we studied a series of mice carrying mutations in sprouty genes, the protein products of which are antagonists of receptor-tyrosine kinase signaling. In sprouty loss-of-function mutants, splitting of gene expression domains and reduced apoptosis was associated with subdivision of the incisor primordium and a multiplication of its stem cell-containing regions. Interestingly, changes in sprouty gene dosage led to a graded change in incisor number, with progressive decreases in sprouty dosage leading to increasing numbers of teeth. Moreover, the independent development of two incisors in mutants with large decreases in sprouty dosage mimicked the likely condition of rodent ancestors. Together, our findings indicate that altering genetic dosage of an antagonist can recapitulate ancestral dental characters, and that tooth number can be progressively regulated by changing levels of activity of a single signal transduction pathway. 相似文献
145.
The physiological status of an organism is able to influence stem cell behaviour to ensure that stem cells meet the needs of the organism during growth, and in response to injury and environmental changes. In particular, the brain is sensitive to metabolic fluctuations. Here we discuss how nutritional status is able to regulate systemic and local insulin/IGF signalling so as to control aspects of neural stem behaviour. Recent results have begun to reveal how systemic signals are relayed to neural stem cells through local interactions with a glial niche. Although much still remains to be discovered, emerging parallels between the regulation of Drosophila and mammalian stem cells suggest a conserved mechanism for how the brain responds to changes in nutritional state. 相似文献
146.
von der Lieth CW Freire AA Blank D Campbell MP Ceroni A Damerell DR Dell A Dwek RA Ernst B Fogh R Frank M Geyer H Geyer R Harrison MJ Henrick K Herget S Hull WE Ionides J Joshi HJ Kamerling JP Leeflang BR Lütteke T Lundborg M Maass K Merry A Ranzinger R Rosen J Royle L Rudd PM Schloissnig S Stenutz R Vranken WF Widmalm G Haslam SM 《Glycobiology》2011,21(4):493-502
The EUROCarbDB project is a design study for a technical framework, which provides sophisticated, freely accessible, open-source informatics tools and databases to support glycobiology and glycomic research. EUROCarbDB is a relational database containing glycan structures, their biological context and, when available, primary and interpreted analytical data from high-performance liquid chromatography, mass spectrometry and nuclear magnetic resonance experiments. Database content can be accessed via a web-based user interface. The database is complemented by a suite of glycoinformatics tools, specifically designed to assist the elucidation and submission of glycan structure and experimental data when used in conjunction with contemporary carbohydrate research workflows. All software tools and source code are licensed under the terms of the Lesser General Public License, and publicly contributed structures and data are freely accessible. The public test version of the web interface to the EUROCarbDB can be found at http://www.ebi.ac.uk/eurocarb. 相似文献
147.
Pauline Ladiges Carlos Parra‐O. Adele Gibbs Frank Udovicic Gareth Nelson Michael Bayly 《Cladistics : the international journal of the Willi Hennig Society》2011,27(1):29-41
Published phylogenies of two eucalypt clades, red bloodwoods Corymbia subgenus Corymbia and eudesmids Eucalyptus subgenus Eudesmia (Myrtaceae), were combined for an analysis of historical biogeographical area relationships within continental Australia. The method of paralogy‐free subtree analysis was used to eliminate geographical paralogy; the paralogy‐free subtrees were coded as characters for parsimony analysis to find the minimal and area cladogram, which proved to be informative of a continent‐wide pattern. The eucalypt fossil record and molecular dating studies allow an interpretation of the biogeographical history in terms of major vicariance events that date from the early Paleogene. The summary area cladogram shows the wet jarrah forest region of South‐West Western Australia, a region of high endemism, as the earliest to differentiate from all other areas, isolated by marine inundation across southern Australia and climatic cooling in the Late Eocene–Early Oligocene. From about this time, regionalization continued, with warmer conditions and monsoonal climate developing in central and northern Australia, and cooling in the south‐east. Northern and eastern humid and semi‐humid areas were related as a track, but with increased aridity in the interior of the continent, the monsoonal climate contracted northwards. The Australian Monsoon Tropics (AMT: Kimberley, Top End, Arnhem, Cape York and inland north‐east Queensland) differentiated from eastern areas (Queensland wet tropics to McPherson–Macleay). Our results also show all arid and semi‐arid regions as related, suggestive of a historically cohesive interior biota rather than repeated colonizations of the interior from the periphery of the continent. Climate largely differentiates hot arid areas in the north (Pilbara, Northern and Central deserts) from arid areas in the south (south‐west interzone, Wheatbelt, Goldfields and Great Victoria Desert). © The Willi Hennig Society 2010. 相似文献
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