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7,9-Diaryl-1,6,8-trioxaspiro[4.5]dec-3-en-2-ones are a recently described group of spirocyclic butenolides that can be generated rapidly and as a single diastereomer through a cascade process between γ-hydroxybutenolides and aromatic aldehydes. The following outlines our findings that these spirocycles are potently cytotoxic and have a dramatic structure–function profile that provides excellent insight into the structural features required for this potency.  相似文献   
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Gastric cancer (GC) is the second most common cause of cancer death worldwide but could be more curable if diagnosed at an earlier stage. At present, the capability to predict the efficaciousness of molecular diagnosis for GC for each patient remains elusive. The purpose of this study was to identify tumor biomarkers through systems analysis of multigene predictors exploiting the available data resource. In this study, we investigated the top 10% overexpressed genes in GC from five data sets of the Oncomine platform, with 265 GC samples versus 174 normal gastric mucosa samples. Sixteen candidate genes were identified as predictors of GC, of which 14 genes were verified through the comparison of expression levels in specimens from normal (chronic gastritis, 21 samples) and GC groups (38 samples). In addition, unique molecular portraits of diffuse adenocarcinoma (DA), intestinal adenocarcinoma (IA), and mixed adenocarcinoma (MA) were studied through Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis, where DA showed higher extracellular matrix alteration while IA and MA showed higher cell-cycle alteration than other types. We also found that the elevated expressions of genes during GC progression were independent of gene mutations, and high core-binding factor subunit β expression is correlated with a high overall survival rate in GC patients. Our research may provide an efficient clinical diagnosis of GC at an early stage with high accuracy and thus help improve the overall survival rate through early therapeutic interventions.  相似文献   
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Abstract The purpose of this study was to investigate possible phylogenetic relationships of a new microorganism called 'Z'. The organism was previously shown to be similar to chlamydia in its growth cycle and some of its metabolic requirements, but different in others and in its major outer membrane protein. In this study we report the sequencing of 'Z's 16S ribosomal DNA and comparison of the sequence with that of other microorganisms, including chlamydia and rickettsiae. While chlamydial species have 95.5% sequence identity among themselves, 'Z' had 83% identity with them, and 73% identity with certain rickettsia-like organisms. Based on the sequence analyses and taking into account physiologic considerations, we believe that 'Z' may belong to a novel genus in the family Chlamydiaceae.  相似文献   
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Diabetic nephropathy (DN) is one of the most serious complications of diabetes worldwide. It is depicted as the leading cause of end-stage renal disease. Oxidative stress plays a key role in hyperglycemia-induced DN. The preparation and characterization of novel mono-, di-, and trisubstituted-s-triazines endowed with uracil and/or thymine are described in this paper. The synthesis of the title compounds was realized through selective nucleophilic substitution reactions of cyanuric chloride with the corresponding hydrazide nucleobases. In this study, we assessed the effects of these derivatives on the progression of diabetic nephropathy. Our results show that trisubstituted-s-triazines endowed with acylhydrazides attenuate high-glucose induced glomerular mesangial cells proliferation and matrix protein accumulation in vitro. Notably, these derivatives also display anti-oxidative properties. This suggests that the novel trisubstituted-s-triazine derivatives provide renal protection through a reactive oxygen species (ROS)-dependent mechanism. Our data provide evidence that these derivatives may serve as potential therapeutic candidates in the treatment of DN.  相似文献   
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《Fungal biology》2014,118(9-10):764-775
This study characterized a novel sugar beet (Beta vulgaris L.) pathogen from the Red River Valley in north central USA, which was formally named Fusarium secorum. Molecular phylogenetic analyses of three loci (translation elongation factor1α, calmodulin, mitochondrial small subunit) and phenotypic data strongly supported the inclusion of F. secorum in the Fusarium fujikuroi species complex (FFSC). Phylogenetic analyses identified F. secorum as a sister taxon of F. acutatum and a member of the African subclade of the FFSC. Fusarium secorum produced circinate hyphae sometimes bearing microconidia and abundant corkscrew-shaped hyphae in culture. To assess mycotoxin production potential, 45 typical secondary metabolites were tested in F. secorum rice cultures, but only beauvericin was produced in detectable amounts by each isolate. Results of pathogenicity experiments revealed that F. secorum isolates are able to induce half- and full-leaf yellowing foliar symptoms and vascular necrosis in roots and petioles of sugar beet. Inoculation with F. acutatum did not result in any disease symptoms. The sugar beet disease caused by F. secorum is named Fusarium yellowing decline. Since Fusarium yellowing decline incidence has been increasing in the Red River Valley, disease management options are discussed.  相似文献   
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Parkinson’s disease (PD) is a common chronic degenerative disease of the central nervous system. Due to a rapidly aging society worldwide, PD morbidity is on the rise; however, the treatment of PD with conventional drugs carries serious adverse reactions and cannot fix the root cause of PD, the degeneration of dopaminergic neurons, which limits conventional drug usage in clinical practice. In recent years, research on the pathogenesis of PD and its clinical manifestations has led to the discovery of an increasing number of novel targets in PD, including several small molecule targeted compounds. In this paper, we analyze and summarize the most recently published PD literature and review several recently discovered novel targets in PD and their small molecule targeted pharmacologically active agents based on their mechanisms of action and pharmacodynamic profiles.  相似文献   
10.
Mikael Calner 《Facies》2005,51(1-4):584-591
Recent and ancient carbonate platforms are major marine ecosystems, built by various carbonate-secreting organisms with different sensitivity for environmental change. For this reason, carbonate platforms are excellent sensors for changes in contemporaneous marine environments. A variety of ecosystem changes in carbonate platforms have previously been recognised in the aftermath of mass extinction events. This paper addresses how two Silurian extinction events among graptolites, conodonts, and pentamerid brachiopods can be related to changes in the style of carbonate production and general evolution of low latitude carbonate platforms in a similar way as previously reported from the major five mass extinctions of the Phanerozoic. Strata formed on Gotland during the Mulde and Lau events share remarkably many similarities but are strikingly different in composition compared to other strata on the island. The event-related strata is characterised by the sudden appearance of widespread oolites, deviating reef composition, flat-pebble conglomerates, abundant micro- and macro-oncoids, stromatolites, and other microbial facies suggesting decreased bioturbation levels in contemporaneous shelf seas. Importantly, these changes can be tied to high-resolution biostratigraphic frameworks and global stable isotope excursions. The anomalous intervals may therefore be searched for elsewhere in order to test their regional or global significance.  相似文献   
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