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991.
Passeri S Nocchi F Lamanna R Lapi S Miragliotta V Giannessi E Abramo F Stornelli MR Matarazzo M Plenteda D Urciuoli P Scatena F Coli A 《Cell biology international》2009,33(1):100-105
Stem cells from extra-embryonic sources can be obtained by non-invasive procedures. We have standardized a method for the expansion of equine umbilical cord-derived matrix cells (EUCMCs) for potential therapy.EUCMCs were isolated from the umbilical cord of five mares immediately after delivery. For expansion, cells were grown in α-MEM and MSCBM. Moreover, to measure the effect of growth factor supplementation, epidermal growth factor (EGF) was added to α-MEM.α-MEM and MSCBM media performed similarly in terms of population doubling and CFU number value. EGF supplementation of α-MEM determined a significant increase of the population doubling value. EGF supplementation did not affect the adipogenic and chondrogenic differentiation while bone nodule sizes an increased with the osteogenic protocol.Both α-MEM and MSCBM can be used to cultivate EUCMCs. α-MEM supplemented with EGF might represent an advantage for EUCMCs expansion. The results could be useful in choosing the culture medium since α-MEM is more cost-effective than MSCBM. 相似文献
992.
Simona Maccherini Giovanni Bacaro Leonardo Favilli Sandro Piazzini Elisa Santi Michela Marignani 《Acta Oecologica》2009,35(2):311-317
Using surrogate taxa in the monitoring of restoration success is strongly advocated but currently under debate. Are butterfly and vascular plant communities good surrogates for each other in monitoring the restoration of calcareous grassland grassland? The research was conducted in a small area in Tuscany (central Italy), which was the focus of a restoration project. We sampled vascular plants using 35 plots (1 m2) and butterflies using 20 transects (100 m in length) belonging to four treatment types: control scrubland, restored ex-arable, restored grassland and reference grassland. A mixed model nested ANOVA showed that reference grassland, 3 years after restoration, had the highest number of vascular plant species and the highest number of butterfly species. The different treatments were found to be distinct from a compositional point of view: pRDA showed that the “treatment” factor, independent of spatial variables, accounted for 22.1 and 21.9% of the total variance in the plant community and butterfly community, respectively (p < 0.01). The butterfly community was significantly correlated with the entire plant community data set and with the phanerophyte community (i.e. shrubs); larval host plants were significantly correlated with the composition of non-migratory butterflies. The results indicated that butterfly and vascular plant communities were congruent, suggesting the use of community composition of different taxa as a valuable tool for the evaluation of management success. 相似文献
993.
Alberto Revelli Delle Luisa Piane Simona Casano Emanuela Molinari Marco Massobrio Paolo Rinaudo 《Reproductive biology and endocrinology : RB&E》2009,7(1):40-13
The assessment of oocyte quality in human in vitro fertilization (IVF) is getting increasing attention from embryologists.
Oocyte selection and the identification of the best oocytes, in fact, would help to limit embryo overproduction and to improve
the results of oocyte cryostorage programs. Follicular fluid (FF) is easily available during oocyte pick-up and theorically
represents an optimal source on non-invasive biochemical predictors of oocyte quality. Unfortunately, however, the studies
aiming to find a good molecular predictor of oocyte quality in FF were not able to identify substances that could be used
as reliable markers of oocyte competence to fertilization, embryo development and pregnancy. In the last years, a well definite
trend toward passing from the research of single molecular markers to more complex techniques that study all metabolites of
FF has been observed. The metabolomic approach is a powerful tool to study biochemical predictors of oocyte quality in FF,
but its application in this area is still at the beginning. This review provides an overview of the current knowledge about
the biochemical predictors of oocyte quality in FF, describing both the results coming from studies on single biochemical
markers and those deriving from the most recent studies of metabolomics 相似文献
994.
Virginie Lopez Rascol Anthony Levasseur Olivier Chabrol Simona Grusea Philippe Gouret Etienne GJ Danchin Pierre Pontarotti 《BMC bioinformatics》2009,10(1):284
Background
Understanding genome evolution provides insight into biological mechanisms. For many years comparative genomics and analysis of conserved chromosomal regions have helped to unravel the mechanisms involved in genome evolution and their implications for the study of biological systems. Detection of conserved regions (descending from a common ancestor) not only helps clarify genome evolution but also makes it possible to identify quantitative trait loci (QTLs) and investigate gene function. 相似文献995.
Personality means suites of correlated behavioural traits, also referred to as “behavioural syndromes” or “personality dimensions”.
Across animal taxa similar combinations of traits seem to prevail, which may have proximate foundation in common neuroendocrine
mechanisms. Hitherto, these have been rarely studied in intact social settings. We investigated personalities of greylag goose
males from a free-roaming flock that shows complex social relationships. In connection with our longitudinal study on the
consistency of behavioural and physiological responses to multiple challenges, we asked whether and how single, personality-related
behavioural traits correlate with each other to form personality dimension(s). We tested whether these dimensions were related
to physiological characteristics that previously showed limited plasticity (heart rate (HR), baseline and stress-induced excreted
immuno-reactive corticosterone (BM), and testosterone metabolites levels) and, furthermore, to age, body measures, and dominance
rank. Principal-components analysis based on behavioural variables revealed two factors: 51.1% of variability was explained
by “aggressiveness” and a further 19.1% by “sociability”. “Aggressiveness” comprised correlated measures of aggression, subordinance,
boldness, vigilance, and proximity to the mate. This “aggressiveness” positively correlated with stress-induced BM levels,
the HR increase during aggressive interactions, and with dominance rank, which may suggest proximate and functional contingencies
of this personality dimension. 相似文献
996.
Gianfranco De Feo Simona Signoriello Jane C. Bryce Antonia Del Giudice Giuliana Canzanella Federika Crudele Fiorella Romano Giovanni de Matteis Manuela Florio Fabiano Falasconi Alfonso Savio Pasqualina Giordano Gennaro Daniele Mario Iaccarino Maria Carmela Piccirillo Massimo Di Maio Alessandro Morabito Ciro Gallo Francesco Perrone 《PloS one》2010,5(7)
997.
Prosperi MC Rosen-Zvi M Altmann A Zazzi M Di Giambenedetto S Kaiser R Schülter E Struck D Sloot P van de Vijver DA Vandamme AM Sönnerborg A;EuResist study group;Virolab study group 《PloS one》2010,5(10):e13753
Background
Although genotypic resistance testing (GRT) is recommended to guide combination antiretroviral therapy (cART), funding and/or facilities to perform GRT may not be available in low to middle income countries. Since treatment history (TH) impacts response to subsequent therapy, we investigated a set of statistical learning models to optimise cART in the absence of GRT information.Methods and Findings
The EuResist database was used to extract 8-week and 24-week treatment change episodes (TCE) with GRT and additional clinical, demographic and TH information. Random Forest (RF) classification was used to predict 8- and 24-week success, defined as undetectable HIV-1 RNA, comparing nested models including (i) GRT+TH and (ii) TH without GRT, using multiple cross-validation and area under the receiver operating characteristic curve (AUC). Virological success was achieved in 68.2% and 68.0% of TCE at 8- and 24-weeks (n = 2,831 and 2,579), respectively. RF (i) and (ii) showed comparable performances, with an average (st.dev.) AUC 0.77 (0.031) vs. 0.757 (0.035) at 8-weeks, 0.834 (0.027) vs. 0.821 (0.025) at 24-weeks. Sensitivity analyses, carried out on a data subset that included antiretroviral regimens commonly used in low to middle income countries, confirmed our findings. Training on subtype B and validation on non-B isolates resulted in a decline of performance for models (i) and (ii).Conclusions
Treatment history-based RF prediction models are comparable to GRT-based for classification of virological outcome. These results may be relevant for therapy optimisation in areas where availability of GRT is limited. Further investigations are required in order to account for different demographics, subtypes and different therapy switching strategies. 相似文献998.
Clementina Auriemma Maurizio Viscardi Simona Tafuri Luigi Michele Pavone Federico Capuano Laura Rinaldi Rossella Della Morte Giuseppe Iovane Norma Staiano 《Cellular & molecular biology letters》2010,15(3):496-506
Listeria monocytogenes enters non-phagocytic cells by binding its surface proteins inlA (internalin) and inlB to the host’s E-cadherin and Met, respectively. The two internalins play either separate or cooperative roles in the colonization
of infected tissues. Here, we studied bacterial uptake into HeLa cells using an L. monocytogenes mutant strain (ΔinlA) carrying a deletion in the gene coding for inlA. The ΔinlA mutant strain showed the capability to invade HeLa cells. The monoclonal anti-β3- and anti-β1-integrin subunit antibodies prevented bacterial uptake into the cells, while the anti-β2- and anti-β4-integrin subunit antibodies failed to affect L. monocytogenes entry into HeLa cells. Three structurally distinct disintegrins (kistrin, echistatin and flavoridin) also inhibited bacterial
uptake, showing different potencies correlated to their selective affinity for the β3- and β1-integrin subunits. In addition to inducing Met phosphorylation, infection of cells by the L. monocytogenes ΔinlA mutant strain promoted the tyrosine phosphorylation of the focal adhesion-associated proteins FAK and paxillin. Our findings
provide the first evidence that β3- and β1-integrin receptors play a role in the inlB-dependent internalization of L. monocytogenes into host cells. 相似文献
999.
1000.
Gianluca Coppola Antonio Currà Cherubino Di Lorenzo Vincenzo Parisi Manuela Gorini Simona Liliana Sava Jean Schoenen Francesco Pierelli 《BMC neurology》2010,10(1):126