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81.
Autosomal-dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease and is characterized by progressive growth of fluid-filled cysts. Growth factors binding to receptor tyrosine kinases (RTKs) stimulate cell proliferation and cyst growth in PKD. Nintedanib, a triple RTK inhibitor, targets the vascular endothelial growth-factor receptor (VEGFR), platelet-derived growth-factor receptor (PDGFR), and fibroblast growth-factor receptor (FGFR), and is an approved drug for the treatment of non-small-cell lung carcinoma and idiopathic lung fibrosis. To determine if RTK inhibition using nintedanib can slow ADPKD progression, we tested its effect on human ADPKD renal cyst epithelial cells and myofibroblasts in vitro, and on Pkd1f/fPkhd1Cre and Pkd1RC/RC, orthologous mouse models of ADPKD. Nintedanib significantly inhibited cell proliferation and in vitro cyst growth of human ADPKD renal cyst epithelial cells, and cell viability and migration of human ADPKD renal myofibroblasts. Consistently, nintedanib treatment significantly reduced kidney-to-body-weight ratio, renal cystic index, cystic epithelial cell proliferation, and blood-urea nitrogen levels in both the Pkd1f/fPkhd1Cre and Pkd1RC/RC mice. There was a corresponding reduction in ERK, AKT, STAT3, and mTOR activity and expression of proproliferative factors, including Yes-associated protein (YAP), c-Myc, and Cyclin D1. Nintedanib treatment significantly reduced fibrosis in Pkd1RC/RC mice, but did not affect renal fibrosis in Pkd1f/fPkhd1Cre mice. Overall, these results suggest that nintedanib may be repurposed to effectively slow cyst growth in ADPKD.Subject terms: Growth factor signalling, Polycystic kidney disease  相似文献   
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We have developed a novel approach to allow for continuous imaging of concentration fields that evolve at surfaces due to release, uptake, and mass transport of molecules, without significant interference of the concentration fields by the chemical imaging itself. The technique utilizes optical “reporter” microbeads immobilized in a thin layer of transparent and inert hydrogel on top of the surface. The hydrogel has minimal density and therefore diffusion in and across it is like in water. Imaging the immobilized microbeads over time provides quantitative concentration measurements at each location where an optical reporter resides. Using image analysis in post-processing these spatially discrete measurements can be transformed into contiguous maps of the dynamic concentration field across the entire surface. If the microbeads are small enough relative to the dimensions of the region of interest and sparsely applied then chemical imaging will not noticeably affect the evolution of concentration fields. In this work colorimetric optode microbeads a few micrometers in diameter were used to image surface concentration distributions on the millimeter scale.  相似文献   
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To construct maternal phylogeny and prehistoric dispersals of modern human being in the Indian sub continent, a diverse subset of 641 complete mitochondrial DNA (mtDNA) genomes belonging to macrohaplogroup M was chosen from a total collection of 2,783 control-region sequences, sampled from 26 selected tribal populations of India. On the basis of complete mtDNA sequencing, we identified 12 new haplogroups - M53 to M64; redefined/ascertained and characterized haplogroups M2, M3, M4, M5, M6, M8′C′Z, M9, M10, M11, M12-G, D, M18, M30, M33, M35, M37, M38, M39, M40, M41, M43, M45 and M49, which were previously described by control and/or coding-region polymorphisms. Our results indicate that the mtDNA lineages reported in the present study (except East Asian lineages M8′C′Z, M9, M10, M11, M12-G, D ) are restricted to Indian region.The deep rooted lineages of macrohaplogroup ‘M’ suggest in-situ origin of these haplogroups in India. Most of these deep rooting lineages are represented by multiple ethnic/linguist groups of India. Hierarchical analysis of molecular variation (AMOVA) shows substantial subdivisions among the tribes of India (Fst = 0.16164). The current Indian mtDNA gene pool was shaped by the initial settlers and was galvanized by minor events of gene flow from the east and west to the restricted zones. Northeast Indian mtDNA pool harbors region specific lineages, other Indian lineages and East Asian lineages. We also suggest the establishment of an East Asian gene in North East India through admixture rather than replacement.  相似文献   
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This research examined cellulolytic effects of fungi and other microbes present in cured sausages on the strength and stability of regenerated cellulose casings (RCC) used in the sausage industry. Occasionally during the curing process, RCC would split or fail, thereby leading to loss of product. The fungus Penicillium sp. BT-F-1, which was isolated from fermented sausages, and other fungi, which were introduced to enable the curing process, produced small amounts of cellulases on RCC in both liquid and solid cultivations. During continued incubation for 15-60 days in solid substrate cultivation (SSC) on RCC support, the fungus Penicillium sp isolate BT-F-1 degraded the casings' dry weights by 15-50% and decreased their tensile strengths by ~75%. Similarly commercial cellulase(s) resulted in 20-50% degradation of RCC in 48 h. During incubation with Penicillium sp BT-F-1, the surface structure of RCC collapsed, resulting in loss of strength and stability of casings. The matrix of industrial RCC comprised 88-93% glucose polymer residues with 0.8-4% xylan impurities. Premature casing failure appeared to result from operating conditions in the manufacturing process that allowed xylan to build up in the extrusion bath. The sausage fungus Penicillium sp BT-F-1 produced xylanases to break down soft xylan pockets prior to slow cellulosic dissolution of RCC.  相似文献   
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The genus Aconitum (consists more than 250 species) is one of the most important clades of highly valued medicinal plants. Aconitum species are very essential in the traditional device of medication and feature excessive business demand in the herbal marketplace. Some of biologically energetic compounds, e.g., aconitine, indaconitine, pseudoacontine, and so on, had been recognized, and new formulations primarily based on those compounds are being produced as rapid rate. This has led to extensive and rather unregulated exploitation of the species in the wild making the genus a threatened group. Conventional breeding and propagation methods have contributed significantly, but these could not meet up with the ever increasing demands of herbal drug industry globally. Biotechnological interventions, therefore, emerge as an alternative approach in terms of higher production and conservation as well. In recent years, several reports have been published on in vitro propagation of various important Aconitum species. However, advanced biotechnological approaches, such as synthetic seed production and hairy root cultures, are still lacking with only a few reports available. The current review presents an updated overview and critical assessment of secondary data concerning the past and recent biotechnological approaches and interventions in genus Aconitum. This review also attempts to provide a detailed account of work explored so far in micropropagation and emphasizes over the areas not attempted yet, which will act as a baseline data as well as valuable information for different stakeholders and researchers working on various aspects of Aconitum biotechnology.  相似文献   
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 The most important commercial species of coffee, Coffea arabica, which produces 73% of the world's coffee crop and almost all of the coffee in Latin America, is the only tetraploid (allotetraploid, 2n=4x=44) species known in the genus. High-frequency somatic embryogenesis, plant regeneration and plant recovery were achieved from leaf explants of a mature, elite plant of C. arabica cv. Cauvery (S-4347) using a two-step culture method. To assess the genetic integrity of the nuclear, mitochondrial and chloroplast genomes among the hardened regenerants, we employed multiple DNA markers (RFLP, RAPD, ISSR) for sampling various regions of the genome. Although the nuclear and mitochondrial genomes of the mother plant and five ramets derived from the mother ortet were similar in organization, this was not so in the somatic embryo-derived plants where both nuclear and mitochondrial genomes changed in different, characteristic ways and produced novel genome organizations. A total of 480 genetic loci, based on the data obtained from a total of 16 nuclear, mitochondrial and chloroplast gene probes, in combination with nine restriction enzyme digests, 38 RAPD and 17 SSR primers, were scored in 27 somatic embryo-derived plants and the single control. Among these, 44 loci were observed to be polymorphic. A relatively low level of polymorphism (4.36%) was found in the nuclear genome, while polymorphism in the mitochondrial genome (41%) was much higher. No polymorphism was detected in the chloroplast genome. The polymorphism in the mitochondrial genome was found in only 4 plants. Such selective polymorphism was not true for the nuclear genome. Thus, this in-depth and comprehensive study demonstrates, for the first time, the presence of subtle genetic variability and novel genome organizations in the commercially well-established somatic embryogenesis-derived plants of this important coffee species. Received: 2 July 1999 / Revision received: 1 February 2000 / Accepted: 17 February 2000  相似文献   
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