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131.
Dukart J Schroeter ML Mueller K;Alzheimer's Disease Neuroimaging Initiative 《PloS one》2011,6(7):e22193
In recent research, many univariate and multivariate approaches have been proposed to improve automatic classification of various dementia syndromes using imaging data. Some of these methods do not provide the possibility to integrate possible confounding variables like age into the statistical evaluation. A similar problem sometimes exists in clinical studies, as it is not always possible to match different clinical groups to each other in all confounding variables, like for example, early-onset (age<65 years) and late-onset (age≥65) patients with Alzheimer's disease (AD). Here, we propose a simple method to control for possible effects of confounding variables such as age prior to statistical evaluation of magnetic resonance imaging (MRI) data using support vector machine classification (SVM) or voxel-based morphometry (VBM). We compare SVM results for the classification of 80 AD patients and 79 healthy control subjects based on MRI data with and without prior age correction. Additionally, we compare VBM results for the comparison of three different groups of AD patients differing in age with the same group of control subjects obtained without including age as covariate, with age as covariate or with prior age correction using the proposed method. SVM classification using the proposed method resulted in higher between-group classification accuracy compared to uncorrected data. Further, applying the proposed age correction substantially improved univariate detection of disease-related grey matter atrophy using VBM in AD patients differing in age from control subjects. The results suggest that the approach proposed in this work is generally suited to control for confounding variables such as age in SVM or VBM analyses. Accordingly, the approach might improve and extend the application of these methods in clinical neurosciences. 相似文献
132.
133.
Becker D Langer E Seemann M Seemann G Fell I Saloga J Grabbe S von Stebut E 《PloS one》2011,6(6):e20566
Background
Therapy of atopic dermatitis (AD) relies on immunosuppression and/or UV irradiation. Here, we assessed clinical efficacy and histopathological alterations induced by blue light-treatment of AD within an observational, non-interventional study.Methodology/Principal Findings
36 patients with severe, chronic AD resisting long term disease control with local corticosteroids were included. Treatment consisted of one cycle of 5 consecutive blue light-irradiations (28.9 J/cm2). Patients were instructed to ask for treatment upon disease exacerbation despite interval therapy with topical corticosteroids. The majority of patients noted first improvements after 2–3 cycles. The EASI score was improved by 41% and 54% after 3 and 6 months, respectively (p≤0.005, and p≤0.002). Significant improvement of pruritus, sleep and life quality was noted especially after 6 months. Also, frequency and intensity of disease exacerbations and the usage of topical corticosteroids was reduced. Finally, immunohistochemistry of skin biopsies obtained at baseline and after 5 and 15 days revealed that, unlike UV light, blue light-treatment did not induce Langerhans cell or T cell depletion from skin.Conclusions/Significance
Blue light-irradiation may represent a suitable treatment option for AD providing long term control of disease. Future studies with larger patient cohorts within a randomized, placebo-controlled clinical trial are required to confirm this observation. 相似文献134.
Mahnaz Mohammadi Jessica Cooper Ognjen Arandelovi Christina Fell David Morrison Sheeba Syed Prakash Konanahalli Sarah Bell Gareth Bryson David J Harrison David Harris-Birtill 《Experimental biology and medicine (Maywood, N.J.)》2022,247(22):2025
Fully supervised learning for whole slide image–based diagnostic tasks in histopathology is problematic due to the requirement for costly and time-consuming manual annotation by experts. Weakly supervised learning that utilizes only slide-level labels during training is becoming more widespread as it relieves this burden, but has not yet been applied to endometrial whole slide images, in iSyntax format. In this work, we apply a weakly supervised learning algorithm to a real-world dataset of this type for the first time, with over 85% validation accuracy and over 87% test accuracy. We then employ interpretability methods including attention heatmapping, feature visualization, and a novel end-to-end saliency-mapping approach to identify distinct morphologies learned by the model and build an understanding of its behavior. These interpretability methods, alongside consultation with expert pathologists, allow us to make comparisons between machine-learned knowledge and consensus in the field. This work contributes to the state of the art by demonstrating a robust practical application of weakly supervised learning on a real-world digital pathology dataset and shows the importance of fine-grained interpretability to support understanding and evaluation of model performance in this high-stakes use case. 相似文献
135.
Xylaria arenicola, X. brasiliensis, X. escharoidea, X. furcata, X. nigripes, X. piperiformis and X. rhizomorpha represent ancient names of fungi known to inhabit abandoned termite nests. We attempt to redescribe them and to reduce the confusion among them. Xylaria tanganyikaensis and X. readeri, species that might be associated with termite nests, are described. We describe a new variety, X. furcata var. hirsuta, and discuss an unnamed fungus that probably represents a new species. Photographs and a key are presented to aid the identification of these taxa. 相似文献
136.
Fell AH Bailey PJ 《ILAR journal / National Research Council, Institute of Laboratory Animal Resources》2005,46(1):65-71
This summary of the experience of the University of California, Davis, in public communications describes the course of applying for funds to build a National Biocontainment Laboratory. Opponents of the project put forward a wide range of arguments falling into two main areas: (1) the safety of the facility and the perceived risk of release of biological agents by accident, theft, or terrorist acts; and (2) concerns that the laboratories would be used for military or secret research beyond the control of the university. The communications strategy in support of the proposal used a number of different tools, including public workshops, direct mail, web sites, and proactive media relations. Communicating in this type of environment is challenging and requires long-term commitments of time and effort, as well as efficient cooperation across departments within the university and externally with local, county, and regional governments, agencies, elected officials, and community members. 相似文献
137.
The structure of interaction products resulting from the reaction of unmodified glucose with benzyl isothiocyanate is reported. Prior to their identification, the main products of this reaction were isolated using solid-phase extraction (SPE) as well as preparative HPLC. They were then identified by NMR and MS as 3-benzyl-4-hydroxy-5-(D-arabino-1,2,3,4-tetrahydroxybutyl)-1,3-oxazolidine-2-thione, 3-benzyl-4-hydroxy-4-hydroxymethyl-5-(D-erythro-1,2,3-trihydroxypropyl)-1,3-oxazolidine-2-thione, N-benzyl-(D-gluco-4,5-dihydroxy-6-hydroxymethyl-tetrahydropyrano)[2,3-b]oxazolidine-2-thione and 3-benzyl-4-(N-benzyl amino)-5-(D-arabino-1,2,3,4-tetrahydroxybutyl)-1,3-thiazolidine-2-thione. The identity of the last compound was secured by X-ray crystal structure data. 相似文献
138.
Hausmann M Bataille F Spoettl T Schreiter K Falk W Schoelmerich J Herfarth H Rogler G 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(3):1389-1398
Intestinal macrophages (IMAC) are a central component in the defense of the intestinal mucosa against luminal microbes. In normal mucosa, monocytes differentiate to immunologically tolerant IMAC with a typical phenotype lacking activation markers such as CD14 and TLRs 2 and 4. CD33+ IMAC were isolated from normal intestinal mucosa by immunomagnetic beads. A subtractive hybridization subtracting mRNA from normal IMAC from those of in vitro differentiated macrophages was performed. IMAC differentiation was studied in multicellular spheroids (MCS). Functional assays on migration of CD45R0+ T cells were performed in MCS coculture models. Of 76 clones, 3 obtained by subtractive mRNA hybridization showed >99% homology to mRNA of MIP-3alpha, indicating that this chemokine is induced in IMAC compared with in vitro differentiated macrophages. MIP-3alpha protein expression was confirmed in cryostat sections of normal intestinal mucosa by immunohistochemistry. IMAC in the lamina propria stained positive for MIP-3alpha. FACS of purified IMAC clearly indicated expression of MIP-3alpha in these cells. In the MCS-in vitro differentiation model for IMAC, MIP-3alpha protein expression was absent on day 1 but detectable on day 7 of coculture, demonstrating the induction of MIP-3alpha during differentiation of IMAC. IMAC attracted CD45R0+ T cells to migrate into an MCS coculture model. In human mucosa, a close contact between IMAC and CD45R0+ T cells could be demonstrated. MIP-3alpha is induced during the differentiation of monocytes into IMAC. Our data suggest that MIP-3alpha expression could be involved in the recruitment of CD45R0+ cells into the lamina propria. 相似文献
139.
Juergen Geist 《Hydrobiologia》2010,644(1):69-88
Freshwater pearl mussels (Margartifera margaritifera L.) are among the most critically threatened freshwater bivalves worldwide. The pearl mussel simultaneously fulfils criteria
of indicator, flagship, keystone and umbrella species and can thus be considered an ideal target species for the process conservation
of aquatic ecosystem functioning. The development of conservation strategies for freshwater pearl mussels and for other bivalve
species faces many challenges, including the selection of priority populations for conservation and strategic decisions on
habitat restoration and/or captive breeding. This article summarises the current information about the species’ systematics
and phylogeny, its distribution and status as well as about its life history strategy and genetic population structure. Based
on this information, integrative conservation strategies for freshwater mollusc species which combine genetic and ecological
information are discussed. Holistic conservation strategies for pearl mussels require the integration of Conservation Genetics
and Conservation Ecology actions at various spatial scales, from the individual and population level to global biodiversity
conservation strategies. The availability of high resolution genetic markers for the species and the knowledge of the critical
stages in the life cycle, particularly of the most sensitive post-parasitic phase, are important prerequisites for conservation.
Effective adaptive conservation management also requires an evaluation of previous actions and management decisions. As with
other freshwater bivalves, an integrative conservation approach that identifies and sustains ecological processes and evolutionary
lineages is urgently needed to protect and manage freshwater pearl mussel diversity. Such research is important for the conservation
of free-living populations, as well as for artificial culturing and breeding techniques, which have recently been or which
are currently being established for freshwater pearl mussels in several countries. 相似文献
140.