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Cerebral ischemia is a cerebrovascular disease with high morbidity and mortality that poses a significant burden on society and the economy. About 60% of cerebral ischemia is caused by thrombus, and the formation of thrombus proceeds from insoluble fibrin, following its transformation from liquid fibrinogen. In thrombus-induced ischemia, increased permeability of the blood–brain barrier (BBB), followed by the extravasation of blood components into the brain results in an altered brain microenvironment. Changes in the brain microenvironment affect brain function and the neurovascular unit (NVU), the working unit of the brain. Recent studies have reported that coagulation factors interact with the NVU and its components, but the specific function of this interaction is highly speculative and warrants further investigations. In this article, we reviewed the role of coagulation factors in cerebral ischemia and the role of coagulation factors in thrombosis. Additionally, the influence of thrombin on the NVU is introduced, as well as in the function of NVU, which may help to explore part of brain injury mechanism during ischemia. Lastly, we propose some novel therapeutic approaches on ischemic stroke by reducing the risk of coagulation.
相似文献Psychrophilic fungi are a critical biotic component in cold deserts that serves a central role in nutrient recycling and biogeochemical cycles. Despite their ecological significance, culture-independent studies on psychrophilic mycobiome are limited. In the present study, the fungal diversity patterns across the Drass, an Indian cold desert in the Himalaya, were indexed by targeted amplicon pyrosequencing (ITS). In the Drass dataset, Ascomycota was represented by 92 genera, while 22 genera represented Basidiomycota. The most abundant genus was Conocybe (20.46%). Most of the identified genera were reported in the literature to be prolific extracellular hydrolytic enzyme producers. To identify whether the Drass fungal assemblages share similarities to other cold deserts, these were further compared to Antarctic and Arctic cold deserts. Comparative analysis across the three cold deserts indicated the dominance of Dikarya (Ascomycota and Basidiomycota). The observed alpha diversity, Shannon index as well as Pielou's evenness was highest in the Antarctic followed by Drass and Arctic datasets. The genera Malassezia, Preussia, Pseudogymnoascus, Cadophora, Geopora, Monodictys, Tetracladium, Titaea, Mortierella, and Cladosporium were common to all the cold deserts. Furthermore, Conocybe was represented predominantly in Drass. Interestingly, the genus Conocybe has not been previously reported from any other studies on Antarctic or Arctic biomes. To the best of our knowledge, this is the first fungal metagenome study in Drass soil. Our analysis shows that despite the similarities of low temperature among the cold deserts, a significant differential abundance of fungal communities prevails in the global cold deserts.
相似文献Width of attached gingiva plays an important role in maintaining periodontal health, provides stabilization of the gingival margin against frictional forces and aids in dissipating physiological forces exerted by the muscular fibers of the alveolar mucosa on the gingival tissues. Inadequate width of attached gingiva leads to attachment loss, soft tissue recession, and impedes oral hygiene measures. Hence, procedures using autografts and allografts have been proposed to augment the attached gingiva. Allografts like chorionic membrane (CM) are known to enhance release of growth factors, promote neovascularization, healing and enhance biotype. To assess the efficacy of CM in increasing the width of attached gingiva, vestibular depth and gingival thickness. Fifteen patients with inadequate attached gingival width were included in the study. Patients were randomly allocated to each group: Control group, CM group and CM?+?platelet rich fibrin (PRF) group. Attached gingiva width, vestibular depth, and gingival thickness were measured at baseline and 4 weeks post procedure. The control, CM and CM?+?PRF groups showed an increase in all parameters from baseline to 4 weeks. The increase in the attached gingiva (p?=?0.042) width, vestibular depth (p?=?0.043) and gingival thickness (p?=?0.034) were statistically significant at 4 weeks for CM group and CM?+?PRF group respectively. The CM?+?PRF group showed better results compared to other groups. CM and PRF can be effectively incorporated to increase the width of attached gingiva and depth of vestibule.
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