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101.
Background
In this study, we used vidagliptin(V) to examine the role of the DDP-IV, incretin system component, in the activation of different molecular inflammatory cytokines, NF-kB and VCAM-1 to generate a microenvironment that supports cardiovascular remodeling.Methods
Male WKY and SHR were separated into five groups: Control, FFR: WKY rats receiving a 10% (w/v) fructose solution during all 12 weeks, SHR, FFHR: SHR receiving a 10% (w/v) fructose solution during all 12 weeks and FFHR+V: (5 mg/kg per day for 6 weeks) (n = 8 each group). Metabolic variables and systolic blood pressure were measured. The TBRAS, eNOS activity, and NAD(P)H oxidase activity were estimated to evaluate oxidative stress. Cardiac and vascular remodeling were evaluated. To assess the cytokine, NF-kB and VCAM-1 immunostaining techniques were used.Results
The FFHR experimental model presents metabolic syndrome criteria, vascular and cardiac remodeling, vascular inflammation due to increased expression of NF-kB, VCAM-1, and pro-atherogenic cytokines. Chronic treatment with V was able to reverse total or partiality of variables studied.Conclusions
Data demonstrated an important effect of DDP-IV in reducing vascular inflammation, accompanied by a favorable reduction in metabolic and structural parameters. 相似文献102.
Joseline Ratnam Barbara Zdrazil Daniela Digles Emiliano Cuadrado-Rodriguez Jean-Marc Neefs Hannah Tipney Ronald Siebes Andra Waagmeester Glyn Bradley Chau Han Chau Lars Richter Jose Brea Chris T. Evelo Edgar Jacoby Stefan Senger Maria Isabel Loza Gerhard F. Ecker Christine Chichester 《PloS one》2014,9(12)
103.
104.
Emiliano Manzo Paola Bartolommei Filippo DellAgnello Roberto Cozzolino 《Ecology and evolution》2022,12(6)
Evidence of abnormal coloration in wild animals provides useful information to better understand its adaptive function and its impact on survival. For this reason, we need to know the frequency and distribution of these abnormal phenotypes in wild populations. Here, we report two records of hypopigmentation in European pine marten Martes martes, obtained during a camera‐trapping survey on Elba Island, Central Italy. We do not know what has caused anomalous coloration of pine marten on Elba Island, but it is possible that the inbreeding may have played a role in this isolated population. Although the light coloration certainly entails an increased visibility of pine martens, it is possible that the low predator pressure and the absence of other wild carnivore populations in our study could mitigate the mortality risk due to the light phenotype. The increased use of camera traps across the world can potentially facilitate the discovery of cases of anomalous colorations in wild populations, providing an unprecedented insight into the occurrence of this phenomenon in wild mammal species. 相似文献
105.
A common cortical substrate activated by horizontal and vertical sound movement in the human brain 总被引:7,自引:0,他引:7
Perception of movement in acoustic space depends on comparison of the sound waveforms reaching the two ears (binaural cues) as well as spectrotemporal analysis of the waveform at each ear (monaural cues). The relative importance of these two cues is different for perception of vertical or horizontal motion, with spectrotemporal analysis likely to be more important for perceiving vertical shifts. In humans, functional imaging studies have shown that sound movement in the horizontal plane activates brain areas distinct from the primary auditory cortex, in parietal and frontal lobes and in the planum temporale. However, no previous work has examined activations for vertical sound movement. It is therefore difficult to generalize previous imaging studies, based on horizontal movement only, to multidimensional auditory space perception. Using externalized virtual-space sounds in a functional magnetic resonance imaging (fMRI) paradigm to investigate this, we compared vertical and horizontal shifts in sound location. A common bilateral network of brain areas was activated in response to both horizontal and vertical sound movement. This included the planum temporale, superior parietal cortex, and premotor cortex. Sounds perceived laterally in virtual space were associated with contralateral activation of the auditory cortex. These results demonstrate that sound movement in vertical and horizontal dimensions engages a common processing network in the human cerebral cortex and show that multidimensional spatial properties of sounds are processed at this level. 相似文献
106.
Marcela A. Garabalino Elisa M. Heber Andrea Monti Hughes Sara J. González Ana J. Molinari Emiliano C. C. Pozzi Susana Nievas Maria E. Itoiz Romina F. Aromando David W. Nigg William Bauer Verónica A. Trivillin Amanda E. Schwint 《Radiation and environmental biophysics》2013,52(3):351-361
Boron neutron capture therapy (BNCT) is based on selective accumulation of 10B carriers in tumor followed by neutron irradiation. We previously proved the therapeutic success of BNCT mediated by the boron compounds boronophenylalanine and sodium decahydrodecaborate (GB-10) in the hamster cheek pouch oral cancer model. Based on the clinical relevance of the boron carrier sodium borocaptate (BSH) and the knowledge that the most effective way to optimize BNCT is to improve tumor boron targeting, the specific aim of this study was to perform biodistribution studies of BSH in the hamster cheek pouch oral cancer model and evaluate the feasibility of BNCT mediated by BSH at nuclear reactor RA-3. The general aim of these studies is to contribute to the knowledge of BNCT radiobiology and optimize BNCT for head and neck cancer. Sodium borocaptate (50 mg 10B/kg) was administered to tumor-bearing hamsters. Groups of 3–5 animals were killed humanely at nine time-points, 3–12 h post-administration. Samples of blood, tumor, precancerous pouch tissue, normal pouch tissue and other clinically relevant normal tissues were processed for boron measurement by optic emission spectroscopy. Tumor boron concentration peaked to therapeutically useful boron concentration values of 24–35 ppm. The boron concentration ratio tumor/normal pouch tissue ranged from 1.1 to 1.8. Pharmacokinetic curves showed that the optimum interval between BSH administration and neutron irradiation was 7–11 h. It is concluded that BNCT mediated by BSH at nuclear reactor RA-3 would be feasible. 相似文献
107.
Cobucci-Ponzano B Zorzetti C Strazzulli A Carillo S Bedini E Corsaro MM Comfort DA Kelly RM Rossi M Moracci M 《Glycobiology》2011,21(4):448-456
The large-scale production of oligosaccharides is a daunting task, hampering the study of the role of glycans in vivo and the testing of the efficacy of novel glycan-based drugs. Glycosynthases, mutated glycosidases that synthesize oligosaccharides in high yields, are becoming important chemo-enzymatic tools for the production of oligosaccharides. However, while β-glycosynthase can be produced with a rather well-established technology, examples of α-glycosynthases are thus far limited only to enzymes from glycoside hydrolase 29 (GH29), GH31 and GH95 families. α-L-Fucosynthases from GH29 use convenient glycosyl azide derivatives as a strategic alternative to glycosyl fluoride donors. However, the general applicability of this method to other α-glycosynthases is not trivial and remains to be confirmed. Here, β-D-galactopyranosyl azide was converted to α-galacto-oligosaccharides with good yields and high regioselectivity, catalyzed by a novel α-galactosynthase based on the GH36 α-galactosidase from the hyperthermophilic bacterium Thermotoga maritima. These results open a new avenue to the practical synthesis of biologically interesting α-galacto-oligosaccharides and demonstrate more widespread use of β-glycosyl-azide as donors, confirming their utility to expand the repertoire of glycosynthases. 相似文献
108.
Marinés de la Peña‐Domene Henry F. Howe Emiliano Cruz‐León Rita Jiménez‐Rolland Cesar Lozano‐Huerta Cristina Martínez‐Garza 《Oikos》2017,126(3):410-419
Recognition that tree recruitment depends on the balance between seed arrival and seedling survival has led to a surge of interest in seed‐dispersal limitation and seedling‐establishment limitation in primary forests. Virtually unaddressed are comparisons of this balance in mature and early successional habitats. We assessed seed rain and seedling recruitment dynamics of tree species in primary forest, secondary forest and pasture released from grazing in a tropical agricultural landscape. Seed to seedling ratios (seed effectiveness; Φi) for 43 species in southern Mexico determined differences in the extent to which seeds produced seedlings by habitat, life history, and dispersal mode. Reproductive potential as estimated by the transition from seed rain to seedling recruitment, differed by habitats, and varied dramatically by life history and dispersal mode. Expected recruit densities (Eit) were higher for animal‐dispersed than wind‐dispersed species, and for non‐pioneer than pioneer species. Non‐pioneers and animal‐dispersed species had higher expected relative recruit abundance (εit) in primary forest (median of 4 seeds recruit?1) whereas in secondary forest wind‐dispersed pioneers had the highest expected relative recruit abundance (median of 16 seeds per recruit). In pastures, wind‐dispersed pioneer species were most successful with many more seeds per recruit (median of 291) than both forest habitats. Seeds per recruit (Φi) appeared to decrease with increase in seed mass for 43 species for which data were available (r = –0.55, P < 0.001). This was associated with a negative correlation of Φi with seed size in primary forest (r = –0.50, P = 0.08 for 13 species); Φi was not correlated with seed size in secondary forest (n = 16) or pasture (n = 14). Metrics of seeds per recruit, expected recruit density and expected relative recruit abundance dramatically illustrate differences in barriers to recruitment in successional habitats. 相似文献
109.
Emiliano Trucchi Paolo Gratton Jason D. Whittington Robin Cristofari Yvon Le Maho Nils Chr Stenseth Céline Le Bohec 《Proceedings. Biological sciences / The Royal Society》2014,281(1787)
How natural climate cycles, such as past glacial/interglacial patterns, have shaped species distributions at the high-latitude regions of the Southern Hemisphere is still largely unclear. Here, we show how the post-glacial warming following the Last Glacial Maximum (ca 18 000 years ago), allowed the (re)colonization of the fragmented sub-Antarctic habitat by an upper-level marine predator, the king penguin Aptenodytes patagonicus. Using restriction site-associated DNA sequencing and standard mitochondrial data, we tested the behaviour of subsets of anonymous nuclear loci in inferring past demography through coalescent-based and allele frequency spectrum analyses. Our results show that the king penguin population breeding on Crozet archipelago steeply increased in size, closely following the Holocene warming recorded in the Epica Dome C ice core. The following population growth can be explained by a threshold model in which the ecological requirements of this species (year-round ice-free habitat for breeding and access to a major source of food such as the Antarctic Polar Front) were met on Crozet soon after the Pleistocene/Holocene climatic transition. 相似文献
110.
Martin Ve
ea Jan Divíek Jonathan Lenoir Borja Jimnez‐Alfaro Idoia Biurrun Ilona Knollov Emiliano Agrillo Juan Antonio Campos Andra arni Guillermo Crespo Jimnez Mirjana uk Panayotis Dimopoulos Jrg Ewald Federico Fernndez‐Gonzlez Jean‐Claude Ggout Adrian Indreica Ute Jandt Florian Jansen Zygmunt Kcki Valerijus Raomavi
ius Marcela ezní
kov John S. Rodwell Joop H.J. Schamine Urban ilc Jens‐Christian Svenning Grzegorz Swacha Kiril Vassilev Roberto Venanzoni Wolfgang Willner Thomas Wohlgemuth Milan Chytrý 《Journal of Biogeography》2019,46(9):1919-1935