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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Richard J. Mills Sean J. Humphrey Patrick R.J. Fortuna Mary Lor Simon R. Foster Gregory A. Quaife-Ryan Rebecca L. Johnston Troy Dumenil Cameron Bishop Rajeev Rudraraju Daniel J. Rawle Thuy Le Wei Zhao Leo Lee Charley Mackenzie-Kludas Neda R. Mehdiabadi Christopher Halliday Dean Gilham James E. Hudson 《Cell》2021,184(8):2167-2182.e22
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Edina Simon Edina Baranyai Mihály Braun István Fábián Béla Tóthmérész 《Biological trace element research》2013,154(1):81-87
Mealworm beetles have been used in numerous experiments as bioindicators. The aim of our experiment was to study the elemental composition in three larvae, pupae and first and second generation adult stages during their life cycle. We selected 180 larvae from a genetically similar population and put them in three groups, in two boxes (60 larvae in each box). Larvae were fed with mashed potato made of the same quality and quantity of potato powder. Then, we selected 10 individuals from each stage to the elemental analysis, using the ICP-OES method. The following elements were analysed in the studied stages: Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Sr and Zn. The results of principal component analysis demonstrated that based on elemental composition, different stages were separated with each other, but in the cases of the three larvae stages, high overlap was found. The results of the GLM ANOVA showed significant differences between the different stages of metamorphosis-based elemental composition. Our results show that the calcium and magnesium were found in a relatively high concentration, while the iron and zinc may be essential elements during the metamorphosis. Our results also show that in insect, the concentration of sodium was higher than in the pupa which may cause by hemolymph. We also demonstrated that the metamorphosis has an effect on the concentration of elements. Our study shows that in the different stages of insects, there are significant changes in the elemental composition of different stages of insects during their metamorphosis. 相似文献
4.
J. Simon 《Zeitschrift fur angewandte Ichthyologie》2013,29(4):909-911
Total length (LT) and total weight (W) measurements of 2576 European eels (Anguilla anguilla) immediately after sampling and again after freezing and defrosting showed that freezing significantly reduced eel LT and W by 1.3 and 6.4%, respectively (P < 0.001). Two formulas for the correction of LT and W of eels after defrosting are given. 相似文献
5.
Aloe vera dry rot caused by Alternaria alternata, is one of the most serious fungal diseases affecting the commercial cultivation of aloe vera in North India. Control of this disease through chemical is quite expensive and not ecofriendly. The plant extracts as biopesticdes act as a vital components for the management of this disease. Evaluation of some plant extracts was carried out against A. alternata in laboratory conditions. The extracts were prepared at 5% and 10% concentration and were evaluated through inhibition in radial growth (food poison technique) and spores (conidia) germination (hanging drop technique) against A. alternata. Neem leaf extract gave 58.6% inhibition in radial growth and 56.5% in spore germination at 10% concentration followed by Ocimum sanctum which was found effective and gave 54.7% inhibition in radial growth and 50.4% in spore germination over control. 相似文献
6.
Nicholas Simon Matthew?L. Bochman Sandlin Seguin Jeffrey?L. Brodsky William?L. Seibel Anthony Schwacha 《Bioscience reports》2013,33(5)
Most currently available small molecule inhibitors of DNA replication lack enzymatic specificity, resulting in deleterious side effects during use in cancer chemotherapy and limited experimental usefulness as mechanistic tools to study DNA replication. Towards development of targeted replication inhibitors, we have focused on Mcm2-7 (minichromosome maintenance protein 2–7), a highly conserved helicase and key regulatory component of eukaryotic DNA replication. Unexpectedly we found that the fluoroquinolone antibiotic ciprofloxacin preferentially inhibits Mcm2-7. Ciprofloxacin blocks the DNA helicase activity of Mcm2-7 at concentrations that have little effect on other tested helicases and prevents the proliferation of both yeast and human cells at concentrations similar to those that inhibit DNA unwinding. Moreover, a previously characterized mcm mutant (mcm4chaos3) exhibits increased ciprofloxacin resistance. To identify more potent Mcm2-7 inhibitors, we screened molecules that are structurally related to ciprofloxacin and identified several that compromise the Mcm2-7 helicase activity at lower concentrations. Our results indicate that ciprofloxacin targets Mcm2-7 in vitro, and support the feasibility of developing specific quinolone-based inhibitors of Mcm2-7 for therapeutic and experimental applications. 相似文献
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Simon Mitternacht Igor N. Berezovsky 《Journal of biomolecular structure & dynamics》2013,31(4):607-609
Abstract Membrane proteins can be classified among the following five types: (1) type I membrane protein. (2) type II membrane protein. (3) multipass transmembrane proteins. (4) lipid chain- anchored membrane proteins, and (5) GPI-anchored membrane proteins. T. Kohonen's self-organization model which is a typical neural network is applied for predicting the type of a given membrane protein based on its amino acid composition. As a result, the high rates of self-consistency (94.80%) and cross-validation (77.76%), and stronger fault-tolerant ability were obtained. 相似文献
9.
Samuel M. Imathiu Simon G. Edwards Rumiana V. Ray Matthew A. Back 《Journal of Phytopathology》2013,161(1):1-10
Fusarium langsethiae is a toxigenic fungus that was formally described as a new species in 2004. This fungus was first detailed in the 1990s but was initially referred to as ‘powdery Fusarium poae’ having a spore morphology similar to F. poae but a mycotoxin profile like that of Fusarium sporotrichioides. The species has been isolated from infected oat, wheat and barley grains but has been reported as more problematic in the former crop rather than the latter two. Whilst the epidemiology of F. langsethiae remains unclear, the fungus has been shown to produce high levels of type‐A trichothecenes HT‐2 and T‐2 toxins in small‐grain cereals. HT‐2 and T‐2 toxins are two of the most potent trichothecenes capable of inhibiting protein synthesis in eukaryotes. In this regard, mycotoxin contamination caused by F. langsethiae is clearly a food and feed safety hazard. With the European Commission considering legislation of HT‐2 and T‐2 toxins, more information is required not only on the producer and conditions favouring mycotoxin production, but also on reliable methods of pathogen detection and reduction of cereal contamination. This review describes recent research concerning the known epidemiology of F. langsethiae and suggestions of what needs to be known about the fungus in order to be able to understand and employ measures for preventing its infection and contamination of cereals with HT‐2 and T‐2 toxins. 相似文献
10.
Thanh Trung Phan Simon James Andrew Turley 《Indian pacing and electrophysiology journal》2013,13(6):221-225
This report describes the successful implantation of a LV lead using balloon venoplasty to overcome a very tight stenosis of the right subclavian vein / brachiocephalic junction for cardiac resynchronisation therapy (CRT-P) in a patient with a right sided CRT-P system and a failed epicardial LV lead. It is important for device implanters to be familiar with interventional equipments and techniques such as balloon venoplasty to overcome difficult venous access. 相似文献