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101.
We have developed the first quantitative trait locus (QTL) analyses for agronomic traits in a cross between F(1.1) (P1) and F(1.7) (P7) entries of Miscanthus sinensis Anderss. Both lines are offspring of the cross between MS-90-2 and MS-88-110. A map based on random amplified polymorphic DNA markers previously constructed was used to perform the QTL analyses. This map was developed using a new mapping strategy that has been designated offspring cross. Eleven QTLs were detected for height, panicle height and diameter using the programme mapqtl 4.0 and the multiple QTL method. QTL significance was determined using several analyses, including Kruskal-Wallis analyses, empirical determination of LOD critical values using permutation tests, QTLs validation with field data over 2 years and co-localization of QTLs for correlated traits. The results obtained could be the first step in developing a marker-assisted selection programming in this species for biomass production.  相似文献   
102.
We have developed a sequence conservation-based artificial neural network predictor called NetDiseaseSNP which classifies nsSNPs as disease-causing or neutral. Our method uses the excellent alignment generation algorithm of SIFT to identify related sequences and a combination of 31 features assessing sequence conservation and the predicted surface accessibility to produce a single score which can be used to rank nsSNPs based on their potential to cause disease. NetDiseaseSNP classifies successfully disease-causing and neutral mutations. In addition, we show that NetDiseaseSNP discriminates cancer driver and passenger mutations satisfactorily. Our method outperforms other state-of-the-art methods on several disease/neutral datasets as well as on cancer driver/passenger mutation datasets and can thus be used to pinpoint and prioritize plausible disease candidates among nsSNPs for further investigation. NetDiseaseSNP is publicly available as an online tool as well as a web service: http://www.cbs.dtu.dk/services/NetDiseaseSNP  相似文献   
103.
The electric dipole moment of solubilized rhodopsin was determined with dielectric dispersion measurements. Rhodopsin was extracted from disc membranes of cattle rod outer segments with the nonionic detergent Triton X-100. The dipole moment of rhodopsin at its isoionic point in the detergent micelle is 720 D (150 charge-A). This value is comparable to dipole moments of nonmembrane proteins, especially those which tend to aggregate or polymerize. Flash irradiation of the rhodopsin results in an increase in the dipole moment of about 25 D (5 charge-A). The light-induced increase in dipole moment appears to be composed of two parts--a faster component related to a change in the number of protons bound by rhodopsin and a slower component apparently independent of the change in proton binding.  相似文献   
104.
4-Pyridyl cyanoguanidines with hydrophobic aromatic side chains showed potent antiproliferative activity in the human breast and lung cancer cell lines MCF-7, NYH and H460. In vivo, treatment with N-(6-chlorophenoxyhexyl)-N′-cyano-N″-4-pyridylguanidine (18, 20 mg/kg/day po.), gave a complete remission of tumours in a model of NYH inoculated nude mice.  相似文献   
105.
106.
The dynamic IV curve method was recently introduced for the efficient experimental generation of reduced neuron models. The method extracts the response properties of a neuron while it is subject to a naturalistic stimulus that mimics in vivo-like fluctuating synaptic drive. The resulting history-dependent, transmembrane current is then projected onto a one-dimensional current–voltage relation that provides the basis for a tractable non-linear integrate-and-fire model. An attractive feature of the method is that it can be used in spike-triggered mode to quantify the distinct patterns of post-spike refractoriness seen in different classes of cortical neuron. The method is first illustrated using a conductance-based model and is then applied experimentally to generate reduced models of cortical layer-5 pyramidal cells and interneurons, in injected-current and injected- conductance protocols. The resulting low-dimensional neuron models—of the refractory exponential integrate-and-fire type—provide highly accurate predictions for spike-times. The method therefore provides a useful tool for the construction of tractable models and rapid experimental classification of cortical neurons.  相似文献   
107.
108.
Imidazole glycerol phosphate dehydratase (IGPD) catalyses the dehydration of imidazole glycerol phosphate to imidazole acetol phosphate, an important late step in the biosynthesis of histidine. IGPD, isolated as a low molecular weight and inactive apo-form, assembles with specific divalent metal cations to form a catalytically active high molecular weight metalloenzyme. Oxo-vanadium ions also assemble the protein into, apparently, the same high molecular weight form but, uniquely, yield a protein without catalytic activity. The VO2+ derivative of IGPD has been investigated by electron paramagnetic resonance (EPR), electron nuclear double resonance (ENDOR) and electron spin echo envelope modulation (ESEEM) spectroscopy. The spin Hamiltonian parameters indicate the presence of multiple 14N nuclei in the inner coordination sphere of VO2+ which is corroborated by ENDOR and ESEEM spectra showing resonances attributable to interactions with 14N nuclei. The isotropic superhyperfine coupling component of about 7 MHz determined by ENDOR is consistent with a nitrogen of coordinated histidine imidazole(s). The ESEEM Fourier-transform spectra further support the notion that the VO2+ substituted enzyme contains inner-sphere nitrogen ligands. The isotropic and anisotropic 14N superhyperfine coupling components are similar to those reported for other equatorially coordinated enzymatic histidine imidazole systems. ESEEM resonances from axial 14N ligands are discussed.  相似文献   
109.
Routinely collected health data, obtained for administrative and clinical purposes without specific a priori research goals, are increasingly used for research. The rapid evolution and availability of these data have revealed issues not addressed by existing reporting guidelines, such as Strengthening the Reporting of Observational Studies in Epidemiology (STROBE). The REporting of studies Conducted using Observational Routinely collected health Data (RECORD) statement was created to fill these gaps. RECORD was created as an extension to the STROBE statement to address reporting items specific to observational studies using routinely collected health data. RECORD consists of a checklist of 13 items related to the title, abstract, introduction, methods, results, and discussion section of articles, and other information required for inclusion in such research reports. This document contains the checklist and explanatory and elaboration information to enhance the use of the checklist. Examples of good reporting for each RECORD checklist item are also included herein. This document, as well as the accompanying website and message board (http://www.record-statement.org), will enhance the implementation and understanding of RECORD. Through implementation of RECORD, authors, journals editors, and peer reviewers can encourage transparency of research reporting.  相似文献   
110.

Background  

The present study aimed to evaluate the efficacy of the hyaluronic acid (HA) binding assay in the selection of motile spermatozoa with normal morphology at high magnification (8400x).  相似文献   
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