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331.
Host interference with expression of the lambda N gene product   总被引:5,自引:0,他引:5  
F Keppel  C P Georgopoulos  H Eisen 《Biochimie》1974,56(11-12):1505-1509
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The Polleniidae (Diptera) are a family of flies best known for species of the genus Pollenia, which overwinter inside human dwellings. Previously divided across the Calliphoridae, Tachinidae and Rhinophoridae, the polleniid genera have only recently been united. Several studies have utilized molecular data to analyse polleniid phylogenetic relationships, although all have suffered from low taxon sampling or insufficient phylogenetic signal in molecular markers. To alleviate these problems, we utilized two automated organellar genome extraction software, GetOrganelle and MitoFinder, to assemble mitogenomes from genome skimming data from 22 representatives of the polleniid genera: Dexopollenia, Melanodexia, Morinia, Pollenia and Xanthotryxus. From these analyses, we provide 14 new mitogenomes for the Polleniidae and perform phylogenetic analyses of 13 protein-coding mitochondrial genes using both maximum likelihood and Bayesian inference. Subfamilial phylogenetic relationships within the Polleniidae are interrogated and Pollenia is found to form a monophyletic clade sister to Melanodexia, Morinia and Dexopollenia, providing no evidence for the synonymisation of any of these genera. Our topology conflicts with previous morphology-based cladistic interpretations, with the amentaria, griseotomentosa, semicinerea and viatica species-groups resolving as non-monophyletic. We provide support for our topology through analysis of adult morphology and male and female terminalia, while identifying new diagnostic characters for some of the clades of the Pollenia. To test the validity of the current diagnostic morphology in the Polleniidae, newly assembled cytochrome C oxidase subunit 1 (COI) data are combined with a polleniid COI barcode reference library and analysed using the species delimitation software ASAP. COI barcodes support the current morphologically defined species within the Pollenia.  相似文献   
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This paper presents a method for determining the structure of the early stage (ES) intermediate in the multistage protein folding process. ES structure is modeled on the basis of a limited conformational subspace of the Ramachandran plot. The model distinguishes seven structural motifs corresponding to seven local probability maxima within the limited conformational subspace. Three of these are assigned to well-defined secondary structures, while the remaining four are found to represent various types of random coils. The presented heuristic approach also provides insight into the reasons behind incorrect predictions occurring when the folding process depends on external factors (e.g., ligands, ions or other proteins) rather than on the characteristics of the backbone itself. The accuracy of the presented method is estimated at around 48 %.  相似文献   
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The major salivary glands of birds develop by branching or elongation of the epithelial cords. The development of the minor salivary glands in form of the lingual glands has never been described. Among birds, only Anatidae have three types of the lingual glands: rostral, caudo‐lateral, and caudo‐medial lingual glands. The study aims to characterize the manner and rate of the lingual glands development in the domestic duck and their topographical arrangement relative to the hyoid apparatus. The study reveals that all three types of the lingual glands develop by branching. We describe five stages of the lingual glands development in the domestic ducks: prebud, initial bud, pseudoglandular, canalicular, and terminal bud stage. The pattern of the lingual glands development in birds is similar to that described for mammals, with the exception, that the terminal buds are formed at the same time as the lumen of the glands. Generally, the rostral lingual gland starts to branch earlier than the caudal lingual glands. The 3D‐reconstruction shows the location and direction of lingual gland development relative to the entoglossal cartilage and basibranchial bone. Light microscopy and scanning electron microscopy allow to characterize the histogenesis of the embryonic epithelium into glandular epithelium. At a time of hatching only secretory units of caudal lingual glands resemble the secretory units of the adult domestic duck. The rostral and caudo‐lateral lingual glands are arranged on the sides of the entoglossal cartilage and basibranchial bone and caudo‐madial lingual glands are located over the basibranchial bone. We suggest that such an arrangement of the lingual glands in the domestic duck is important during food intake and responsible for reduction of friction and formation of food bites.  相似文献   
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Intracellular heat shock protein (Hsp) 27 is a potent anti-apoptotic factor that, among other activities, prevents the binding of membrane receptor Fas to its ligand FasL. However, the potential role of extracellular Hsp27 and possibilities to control it have not been clarified. Moreover, there are no data on relations between Hsp27, sFas/sFasL system, matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in patients with chronic kidney disease (CKD)—neither children nor adults. The aim of this study was to evaluate serum concentrations of Hsp27 and their potential regulators (sFas, sFasL, MMP-7, TIMP-1) in children with CKD and on chronic dialysis. Twenty-six CKD children stage 5 still on conservative treatment, 19 patients on hemodialysis (HD), 22 children on automated peritoneal dialysis (APD), and 30 controls were examined. Serum concentrations of Hsp27, sFas, sFasL, MMP-7, and TIMP-1 were assessed by ELISA. Median values of Hsp27 were significantly elevated in all dialyzed patients vs. those in pre-dialysis period and vs. controls, the highest values being observed in subjects on HD. Regression analysis revealed that MMP-7, TIMP-1, sFas, and sFasL were the best predictors of Hsp27 concentrations in dialyzed patients. Children with CKD are prone to Hsp27 dysfunction, aggravated by the dialysis commencement, and more pronounced in patients on hemodialysis. Correlations between Hsp27 and examined parameters suggest the potential role for Hsp27 as a marker of cell damage in the pediatric population on chronic dialysis.  相似文献   
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Photosynthesis Research - In Synechocystis sp. PCC 6803 and some other cyanobacteria photosystem I reaction centres exist predominantly as trimers, with minor contribution of monomeric form, when...  相似文献   
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