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981.
Giulia Bernardini Gemma Leone Lia Millucci Marco Consumi Daniela Braconi Ottavia Spiga Silvia Galderisi Barbara Marzocchi Cecilia Viti Giovanna Giorgetti Pietro Lupetti Agnese Magnani Annalisa Santucci 《Journal of cellular physiology》2019,234(5):6696-6708
Alkaptonuria (AKU) is a disease caused by a deficient homogentisate 1,2-dioxygenase activity leading to systemic accumulation of homogentisic acid (HGA), that forms a melanin-like polymer that progressively deposits onto connective tissues causing a pigmentation called “ochronosis” and tissue degeneration. The effects of AKU and ochronotic pigment on the biomechanical properties of articular cartilage need further investigation. To this aim, AKU cartilage was studied using thermal (thermogravimetry and differential scanning calorimetry) and rheological analysis. We found that AKU cartilage had a doubled mesopore radius compared to healthy cartilage. Since the mesoporous structure is the main responsible for maintaining a correct hydrostatic pressure and tissue homoeostasis, drastic changes of thermal and rheological parameters were found in AKU. In particular, AKU tissue lost its capability to enhance chondrocytes metabolism (decreased heat capacity) and hence the production of proteoglycans. A drastic increase in stiffness and decrease in dissipative and lubricant role ensued in AKU cartilage. Multiphoton and scanning electron microscopies revealed destruction of cell–matrix microstructure and disruption of the superficial layer. Such observations on AKU specimens were confirmed in HGA-treated healthy cartilage, indicating that HGA is the toxic responsible of morphological and mechanical alterations of cartilage in AKU. 相似文献
982.
Maurício Luiz Vilela Daniela de Pita-Pereira Carina Graser Azevedo Rodrigo Espíndola Godoy Constan?a Britto Elizabeth Ferreira Rangel 《Memórias do Instituto Oswaldo Cruz》2013,108(5):578-585
Phlebotomine sandflies were captured in rural settlement and periurban
areas of the municipality of Guaraí in the state of Tocantins (TO), an endemic
area of American cutaneous leishmaniasis (ACL). Forty-three phlebotomine species
were identified, nine of which have already been recognised as ACL vectors.
Eleven species were recorded for the first time in TO. Nyssomyia
whitmani was the most abundant species, followed by
Evandromyia bourrouli, Nyssomyia antunesi
and Psychodopygus complexus. The Shannon-Wiener diversity index
and the evenness index were higher in the rural settlement area than in the
periurban area. The evaluation of different ecotopes within the rural area
showed the highest frequencies of Ev. bourrouli and Ny.
antunesi in chicken coops, whereas Ny. whitmani
predominated in this ecotope in the periurban area. In the rural settlement
area, Ev. bourrouli was the most frequently captured species in
automatic light traps and Ps. complexus was the most prevalent
in Shannon trap captures. The rural settlement environment exhibited greater
phlebotomine biodiversity than the periurban area. Ps.
complexus and Psychodopygus ayrozai naturally
infected with Leishmania (Viannia) braziliensis were
identified. The data identified Ny. whitmani as a potential ACL
vector in the periurban area, whereas Ps. complexus was more
prevalent in the rural environment associated with settlements. 相似文献
983.
Markus Auer Clemens Gruber Marzia Bellei Katharina F. Pirker Marcel Zamocky Daniela Kroiss Stefan A. Teufer Stefan Hofbauer Monika Soudi Gianantonio Battistuzzi Paul G. Furtmüller Christian Obinger 《The Journal of biological chemistry》2013,288(38):27181-27199
Reconstructing the phylogenetic relationships of the main evolutionary lines of the mammalian
peroxidases lactoperoxidase and myeloperoxidase revealed the presence of novel bacterial heme
peroxidase subfamilies. Here, for the first time, an ancestral bacterial heme peroxidase is shown to
possess a very high bromide oxidation activity (besides conventional peroxidase activity). The
recombinant protein allowed monitoring of the autocatalytic peroxide-driven formation of covalent
heme to protein bonds. Thereby, the high spin ferric rhombic heme spectrum became similar to
lactoperoxidase, the standard reduction potential of the Fe(III)/Fe(II) couple shifted to more
positive values (−145 ± 10 mV at pH 7), and the conformational and thermal stability
of the protein increased significantly. We discuss structure-function relationships of this new
peroxidase in relation to its mammalian counterparts and ask for its putative physiological
role. 相似文献
984.
In diagnostic studies, a new diagnostic test is often compared with a standard test and both tests are applied on the same patients, called paired design. The true disease state is in general given by the so‐called gold standard (most reliable method for classification), which has to be known for all patients. The benefit of the new diagnostic test can be evaluated by sensitivity and specificity, which are in fact proportions. This means, for the comparison of two diagnostic tests, confidence intervals for the difference of the dependent estimated sensitivities and specificities are calculated. In the literature, many comparisons of different approaches can be found, but none explicitly for diagnostic studies. For this reason we compare 13 approaches for a set of scenarios that represent data of diagnostic studies (e.g., with sensitivity and specificity ?0.8). With simulation studies, we show that the nonparametric interval with normal approximation can be recommended for the difference of two dependent sensitivities or specificities without restriction, the Wald interval with the limitation of slightly anti‐conservative results for small sample sizes, and the nonparametric intervals with t‐approximation, and the Tango interval with the limitation of conservative results for high correlations. 相似文献
985.
Aim Pockmarks are craters on the sea floor formed by sub‐sea‐floor fluid expulsions, which occur world‐wide at all ocean depths. These habitats potentially host a highly specialized fauna that can exploit the hydrocarbons released. Pockmarks at relatively shallow depths can be easily destroyed by human activities, such as bottom trawling. In the present study, we investigated the combined effects of sea‐floor heterogeneity, rate of fluid emission and trophic conditions of different pockmarks on the biodiversity of the deep‐sea assemblages. Location Continental slope of the Gulf of Lions, western Mediterranean Sea, at water depths from 265 to 434 m. Methods We investigated the biodiversity associated with sea‐floor pockmarks that are both inactive and that have active gas emissions. Control sites were selected on the sea floor outside the influence of the gas seepage, both within and outside the pockmark fields. We examined the combined effects of: (i) sea‐floor heterogeneity; (ii) variable levels of fluid (gas) emissions; and (iii) trophic characteristics of the meiofaunal assemblage structure and nematode diversity. Results Sediments within the pockmark fields had lower meiofaunal abundance and biomass when compared with the surrounding sediments that were not influenced by the gas seepage. Although several higher taxa were absent in the pockmarks (e.g. Turbellaria, Tardigrada, Cumacea, Isopoda, Tanaidacea, Nemertina and Priapulida, which were present in the control areas), the richness of the nematode species within all of these pockmarks was very high. About 25% of the total species encountered in the deep‐sea sediments of the investigated areas was exclusively associated with these pockmarks. Main conclusions We conclude that both active and inactive pockmarks provide significant contributions to the regional (gamma) diversity of the continental slope in the western Mediterranean Sea, and thus the protection of these special and fragile habitats is highly relevant to the conservation of deep‐sea biodiversity. 相似文献
986.
987.
Mara Castelli Giada Amodeo Lucia Negri Roberta Lattanzi Daniela Maftei Cecilia Gotti Francesco Pistillo Valentina Onnis Cenzo Congu Alberto E. Panerai Paola Sacerdote Silvia Franchi 《PloS one》2016,11(1)
Neuropathic pain is a severe diabetes complication and its treatment is not satisfactory. It is associated with neuroinflammation-related events that participate in pain generation and chronicization. Prokineticins are a new family of chemokines that has emerged as critical players in immune system, inflammation and pain. We investigated the role of prokineticins and their receptors as modulators of neuropathic pain and inflammatory responses in experimental diabetes. In streptozotocin-induced-diabetes in mice, the time course expression of prokineticin and its receptors was evaluated in spinal cord and sciatic nerves, and correlated with mechanical allodynia. Spinal cord and sciatic nerve pro- and anti-inflammatory cytokines were measured as protein and mRNA, and spinal cord GluR subunits expression studied. The effect of preventive and therapeutic treatment with the prokineticin receptor antagonist PC1 on behavioural and biochemical parameters was evaluated. Peripheral immune activation was assessed measuring macrophage and T-helper cytokine production. An up-regulation of the Prokineticin system was present in spinal cord and nerves of diabetic mice, and correlated with allodynia. Therapeutic PC1 reversed allodynia while preventive treatment blocked its development. PC1 normalized prokineticin levels and prevented the up-regulation of GluN2B subunits in the spinal cord. The antagonist restored the pro-/anti-inflammatory cytokine balance altered in spinal cord and nerves and also reduced peripheral immune system activation in diabetic mice, decreasing macrophage proinflammatory cytokines and the T-helper 1 phenotype. The prokineticin system contributes to altered sensitivity in diabetic neuropathy and its inhibition blocked both allodynia and inflammatory events underlying disease. 相似文献
988.
989.
Claudio Corallo Emilio Battisti Antonietta Albanese Daniela Vannoni Roberto Leoncini Giacomo Landi 《Electromagnetic biology and medicine》2014,33(1):3-10
Osteoarthritis (OA) is the most frequent joint disease, characterized by degradation of extracellular matrix and alterations in chondrocyte metabolism. Some authors reported that electromagnetic fields (EMFs) can positively interfere with patients affected by OA, even though the nature of the interaction is still debated. Human primary osteoarthritic chondrocytes isolated from the femoral heads of OA-patients undergoing to total hip replacement, were cultured in vitro and exposed 30?min/day for two weeks to extremely-low-frequency electromagnetic field (ELF) with fixed frequency (100?Hz) and to therapeutic application of musically modulated electromagnetic fields (TAMMEF) with variable frequencies, intensities and waveforms. Sham-exposed (S.E.) cells served as control group. Cell viability was measured at days 2, 7 and 14. After two weeks, cell lysates were processed using a proteomic approach. Chondrocyte exposed to ELF and TAMMEF system demonstrated different viability compared to untreated chondrocytes (S.E.). Proteome analysis of 2D-Electrophoresis and protein identification by mass spectrometry showed different expression of proteins derived from nucleus, cytoplasm and organelles. Function analysis of the identified proteins showed changes in related-proteins metabolism (glyceraldeyde-3-phosphate-dehydrogenase), stress response (Mn-superoxide-dismutase, heat-shock proteins), cytoskeletal regulation (actin), proteinase inhibition (cystatin-B) and inflammation regulatory functions (S100-A10, S100-A11) among the experimental groups (ELF, TAMMEF and S.E.). In conclusion, EMFs do not cause damage to chondrocytes, besides stimulate safely OA-chondrocytes and are responsible of different protein expression among the three groups. Furthermore, protein analysis of OA-chondrocytes treated with ELF and the new TAMMEF systems could be useful to clarify the pathogenetic mechanisms of OA by identifying biomarkers of the disease. 相似文献
990.
Daniela Peters Jana Berger Kristina Langnaese Christian Derst Vince I. Madai Michael Krauss Klaus-Dieter Fischer Rüdiger W. Veh Gregor Laube 《PloS one》2013,8(6)
Polyamines are important regulators of basal cellular functions but also subserve highly specific tasks in the mammalian brain. With this respect, polyamines and the synthesizing and degrading enzymes are clearly differentially distributed in neurons versus glial cells and also in different brain areas. The synthesis of the diamine putrescine may be driven via two different pathways. In the “classical” pathway urea and carbon dioxide are removed from arginine by arginase and ornithine decarboxylase. The alternative pathway, first removing carbon dioxide by arginine decarboxlyase and then urea by agmatinase, may serve the same purpose. Furthermore, the intermediate product of the alternative pathway, agmatine, is an endogenous ligand for imidazoline receptors and may serve as a neurotransmitter. In order to evaluate and compare the expression patterns of the two gate keeper enzymes arginase and arginine decarboxylase, we generated polyclonal, monospecific antibodies against arginase-1 and arginine decarboxylase. Using these tools, we immunocytochemically screened the rat brain and compared the expression patterns of both enzymes in several brain areas on the regional, cellular and subcellular level. In contrast to other enzymes of the polyamine pathway, arginine decarboxylase and arginase are both constitutively and widely expressed in rat brain neurons. In cerebral cortex and hippocampus, principal neurons and putative interneurons were clearly labeled for both enzymes. Labeling, however, was strikingly different in these neurons with respect to the subcellular localization of the enzymes. While with antibodies against arginine decarboxylase the immunosignal was distributed throughout the cytoplasm, arginase-like immunoreactivity was preferentially localized to Golgi stacks. Given the apparent congruence of arginase and arginine decarboxylase distribution with respect to certain cell populations, it seems likely that the synthesis of agmatine rather than putrescine may be the main purpose of the alternative pathway of polyamine synthesis, while the classical pathway supplies putrescine and spermidine/spermine in these neurons. 相似文献