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991.
992.
Georgios Tsivgoulis Aristeidis H. Katsanos Nikolaos Grigoriadis Georgios M. Hadjigeorgiou Ioannis Heliopoulos Constantinos Kilidireas Konstantinos Voumvourakis 《PloS one》2015,10(3)
Background
The aim of the present meta-analysis was to evaluate the effect of disease-modifying drugs (DMD) on brain atrophy in patients with relapsing-remitting multiple sclerosis (RRMS) using available randomized-controlled trial (RCT) data.Methods
We conducted a systematic review and meta-analysis according to PRISMA guidelines of all available RCTs of patients with RRMS that reported data on brain volume measurements during the study period.Results
We identified 4 eligible studies, including a total of 1819 RRMS patients (71% women, mean age 36.5 years, mean baseline EDSS-score: 2.4). The mean percentage change in brain volume was found to be significantly lower in DMD versus placebo subgroup (standardized mean difference: -0.19; 95%CI: -0.27–-0.11; p<0.001). We detected no evidence of heterogeneity between estimates (I2 = 30%, p = 0.19) nor publication bias in the Funnel plots. Sensitivity analyses stratifying studies according to brain atrophy neuroimaging protocol disclosed no evidence of heterogeneity (p = 0.16). In meta-regression analyses, the percentage change in brain volume was found to be inversely related with duration of observation period in both DMD (meta-regression slope = -0.03; 95% CI: -0.04–-0.02; p<0.001) and placebo subgroups (meta-regression slope = -0.05; 95% CI: -0.06–-0.04; p<0.001). However, the rate of percentage brain volume loss over time was greater in placebo than in DMD subgroup (p = 0.017, ANCOVA).Conclusions
DMD appear to be effective in attenuating brain atrophy in comparison to placebo and their benefit in delaying the rate of brain volume loss increases linearly with longer treatment duration. 相似文献993.
Ioannis N. Petropoulos Patrick Green Agnes W. S. Chan Uazman Alam Hassan Fadavi Andrew Marshall Omar Asghar Nathan Efron Mitra Tavakoli Rayaz A. Malik 《PloS one》2015,10(4)
Objective
Corneal innervation is increasingly used as a surrogate marker of human diabetic peripheral neuropathy (DPN) however its temporal relationship with the other microvascular complications of diabetes is not fully established. In this cross-sectional, observational study we aimed to assess whether neuropathy occurred in patients with type 1 diabetes, without retinopathy or microalbuminuria.Materials and Methods
All participants underwent detailed assessment of peripheral neuropathy [neuropathy disability score (NDS), vibration perception threshold (VPT), peroneal motor nerve conduction velocity (PMNCV), sural sensory nerve conduction velocity (SSNCV) and in vivo corneal confocal microscopy (IVCCM)], retinopathy (digital fundus photography) and albuminuria status [albumin: creatinine ratio (ACR)].Results
53 patients with Type 1 diabetes with (n=37) and without retinopathy (n=16) were compared to control subjects (n=27). SSNCV, corneal nerve fibre (CNFD) and branch (CNBD) density and length (CNFL) were reduced significantly (p<0.001) in diabetic patients without retinopathy compared to control subjects. Furthermore, CNFD, CNBD and CNFL were also significantly (p<0.001) reduced in diabetic patients without microalbuminuria (n=39), compared to control subjects. Greater neuropathic severity was associated with established retinopathy and microalbuminuria.Conclusions
IVCCM detects early small fibre damage in the absence of retinopathy or microalbuminuria in patients with Type 1 diabetes. 相似文献994.
Maria Ida Iacono Esra Neufeld Esther Akinnagbe Kelsey Bower Johanna Wolf Ioannis Vogiatzis Oikonomidis Deepika Sharma Bryn Lloyd Bertram J. Wilm Michael Wyss Klaas P. Pruessmann Andras Jakab Nikos Makris Ethan D. Cohen Niels Kuster Wolfgang Kainz Leonardo M. Angelone 《PloS one》2015,10(4)
Computational modeling and simulations are increasingly being used to complement experimental testing for analysis of safety and efficacy of medical devices. Multiple voxel- and surface-based whole- and partial-body models have been proposed in the literature, typically with spatial resolution in the range of 1–2 mm and with 10–50 different tissue types resolved. We have developed a multimodal imaging-based detailed anatomical model of the human head and neck, named “MIDA”. The model was obtained by integrating three different magnetic resonance imaging (MRI) modalities, the parameters of which were tailored to enhance the signals of specific tissues: i) structural T1- and T2-weighted MRIs; a specific heavily T2-weighted MRI slab with high nerve contrast optimized to enhance the structures of the ear and eye; ii) magnetic resonance angiography (MRA) data to image the vasculature, and iii) diffusion tensor imaging (DTI) to obtain information on anisotropy and fiber orientation. The unique multimodal high-resolution approach allowed resolving 153 structures, including several distinct muscles, bones and skull layers, arteries and veins, nerves, as well as salivary glands. The model offers also a detailed characterization of eyes, ears, and deep brain structures. A special automatic atlas-based segmentation procedure was adopted to include a detailed map of the nuclei of the thalamus and midbrain into the head model. The suitability of the model to simulations involving different numerical methods, discretization approaches, as well as DTI-based tensorial electrical conductivity, was examined in a case-study, in which the electric field was generated by transcranial alternating current stimulation. The voxel- and the surface-based versions of the models are freely available to the scientific community. 相似文献
995.
Nicolas Guex Isaac Crespo Sylvian Bron Assia Ifticene-Treboux Eveline Faes-van’t Hull Solange Kharoubi Robin Liechti Patricia Werffeli Mark Ibberson Francois Majo Mich?el Nicolas Julien Laurent Abhishek Garg Khalil Zaman Hans-Anton Lehr Brian J. Stevenson Curzio Rüegg George Coukos Jean-Fran?ois Delaloye Ioannis Xenarios Marie-Agnès Doucey 《PLoS computational biology》2015,11(3)
Angiogenesis plays a key role in tumor growth and cancer progression. TIE-2-expressing monocytes (TEM) have been reported to critically account for tumor vascularization and growth in mouse tumor experimental models, but the molecular basis of their pro-angiogenic activity are largely unknown. Moreover, differences in the pro-angiogenic activity between blood circulating and tumor infiltrated TEM in human patients has not been established to date, hindering the identification of specific targets for therapeutic intervention. In this work, we investigated these differences and the phenotypic reversal of breast tumor pro-angiogenic TEM to a weak pro-angiogenic phenotype by combining Boolean modelling and experimental approaches. Firstly, we show that in breast cancer patients the pro-angiogenic activity of TEM increased drastically from blood to tumor, suggesting that the tumor microenvironment shapes the highly pro-angiogenic phenotype of TEM. Secondly, we predicted in silico all minimal perturbations transitioning the highly pro-angiogenic phenotype of tumor TEM to the weak pro-angiogenic phenotype of blood TEM and vice versa. In silico predicted perturbations were validated experimentally using patient TEM. In addition, gene expression profiling of TEM transitioned to a weak pro-angiogenic phenotype confirmed that TEM are plastic cells and can be reverted to immunological potent monocytes. Finally, the relapse-free survival analysis showed a statistically significant difference between patients with tumors with high and low expression values for genes encoding transitioning proteins detected in silico and validated on patient TEM. In conclusion, the inferred TEM regulatory network accurately captured experimental TEM behavior and highlighted crosstalk between specific angiogenic and inflammatory signaling pathways of outstanding importance to control their pro-angiogenic activity. Results showed the successful in vitro reversion of such an activity by perturbation of in silico predicted target genes in tumor derived TEM, and indicated that targeting tumor TEM plasticity may constitute a novel valid therapeutic strategy in breast cancer. 相似文献
996.
?smund H. Eikenes Lene Maler?d Anette Lie Christensen Chloé B. Steen Juliette Mathieu Ioannis P. Nezis Knut Liest?l Jean-René Huynh Harald Stenmark Kaisa Haglund 《PLoS genetics》2015,11(1)
Abscission is the final step of cytokinesis that involves the cleavage of the intercellular bridge connecting the two daughter cells. Recent studies have given novel insight into the spatiotemporal regulation and molecular mechanisms controlling abscission in cultured yeast and human cells. The mechanisms of abscission in living metazoan tissues are however not well understood. Here we show that ALIX and the ESCRT-III component Shrub are required for completion of abscission during Drosophila female germline stem cell (fGSC) division. Loss of ALIX or Shrub function in fGSCs leads to delayed abscission and the consequent formation of stem cysts in which chains of daughter cells remain interconnected to the fGSC via midbody rings and fusome. We demonstrate that ALIX and Shrub interact and that they co-localize at midbody rings and midbodies during cytokinetic abscission in fGSCs. Mechanistically, we show that the direct interaction between ALIX and Shrub is required to ensure cytokinesis completion with normal kinetics in fGSCs. We conclude that ALIX and ESCRT-III coordinately control abscission in Drosophila fGSCs and that their complex formation is required for accurate abscission timing in GSCs in vivo. 相似文献
997.
Agronomic Practices for Improving Gentle Remediation of Trace Element-Contaminated Soils 总被引:1,自引:0,他引:1
Petra Kidd Michel Mench Vanessa Álvarez-López Valérie Bert Ioannis Dimitriou Wolfgang Friesl-Hanl 《International journal of phytoremediation》2015,17(11):1005-1037
The last few decades have seen the rise of Gentle soil Remediation Options (GRO), which notably include in situ contaminant stabilization (“inactivation”) and plant-based (generally termed “phytoremediation”) options. For trace element (TE)-contaminated sites, GRO aim to either decrease their labile pool and/or total content in the soil, thereby reducing related pollutant linkages. Much research has been dedicated to the screening and selection of TE-tolerant plant species and genotypes for application in GRO. However, the number of field trials demonstrating successful GRO remains well below the number of studies carried out at a greenhouse level. The move from greenhouse to field conditions requires incorporating agronomical knowledge into the remediation process and the ecological restoration of ecosystem services. This review summarizes agronomic practices against their demonstrated or potential positive effect on GRO performance, including plant selection, soil management practices, crop rotation, short rotation coppice, intercropping/row cropping, planting methods and plant densities, harvest and fertilization management, pest and weed control and irrigation management. Potentially negative effects of GRO, e.g., the introduction of potentially invasive species, are also discussed. Lessons learnt from long-term European field case sites are given for aiding the choice of appropriate management practices and plant species. 相似文献
998.
999.
Aliki Xochelli Andreas Agathangelidis Ioannis Kavakiotis Evangelia Minga Lesley Ann Sutton Panagiotis Baliakas Ioanna Chouvarda Véronique Giudicelli Ioannis Vlahavas Nikos Maglaveras Lisa Bonello Livio Trentin Alessandra Tedeschi Panagiotis Panagiotidis Christian Geisler Anton W. Langerak Sarka Pospisilova Diane F. Jelinek David Oscier Nicholas Chiorazzi Nikos Darzentas Fred Davi Paolo Ghia Richard Rosenquist Anastasia Hadzidimitriou Chrysoula Belessi Marie-Paule Lefranc Kostas Stamatopoulos 《Immunogenetics》2015,67(1):61-66
1000.