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31.
F.t.-i.r. and laser-Raman spectra of thymine and thymidine in the solid state were recorded. Assignments were proposed for the frequencies observed. The influence of the deoxy sugar on the vibrations of the nucleoside are discussed as a function of its particular puckering. The aim of this work is to elucidate the differences between the molecules constituting the nucleic acids, in order the better to comprehend their biological functions. 相似文献
32.
Human CD59 Incorporation into Porcine Endogenous Retrovirus Particles: Implications for the Use of Transgenic Pigs for Xenotransplantation 下载免费PDF全文
Daniel M. Takefman Gregory T. Spear Mohammed Saifuddin Carolyn A. Wilson 《Journal of virology》2002,76(4):1999-2002
Transgenic pigs have been engineered to express human CD59 (hCD59) in order to suppress hyperacute rejection of xenotransplants in human recipients. In this study, porcine endogenous retrovirus (PERV) was produced in a porcine cell line expressing hCD59 in order to examine the effect of this complement control protein on PERV neutralization by human sera. hCD59 was found to be incorporated into PERV particles produced from engineered ST-IOWA cells. PERV incorporation of hCD59 resulted in a dramatic inhibition of complement-mediated virolysis by human serum. However, incorporation of hCD59 had no effect on neutralization of PERV by human serum, as measured in infectivity assays. Our results suggest that the use of organs from hCD59 transgenic pigs will inhibit complement-mediated virolysis, but will not compromise the protective effects of human sera on the neutralization of PERV particles. 相似文献
33.
Ana Milstein Mohammed Ekram Azim Mohammed Abdul Wahab Marc Charles Jean Verdegem 《Environmental Biology of Fishes》2003,68(3):247-260
The potential of periphyton-based aquaculture in South Asia is under investigation in an extensive research program. This paper is a further analysis of data from four experiments carried out in that framework, to explore periphyton, fish and fertilizer dose effects on water quality. Factor analysis and ANOVA models applied to a data matrix of water quality parameters in ponds with and without artificial substrates (bamboo poles and kanchi sticks), with and without fish (filter feeders catla and rohu, with and without bottom feeder kalbaush), and with a standard or 50% increased fertilizer dose, allowed us to identify the underlying ecological processes governing this novel periphyton-based pond system, and construct conceptual graphic models of the periphyton–environment relationships observed. We clearly established that the phosphorus flow is mainly linked to phytoplankton activity in the water column and decomposition on the pond bottom, while nitrogen flow is mainly linked to autotrophic (photosynthesis) and heterotrophic (decomposition and nitrification) processes that take place in the periphyton in addition to the water column and pond bottom. Consequently, disruption of the pond bottom by bottom feeding fish primarily promoted phosphate cycling and phytoplankton, while periphyton development on the supplied substrates and fertilization mainly improved oxygen balance and nitrogen related processes developing in the water column. The use of bamboo poles led to better results than kanchi sticks, related to the greater autotrophic periphyton development on bamboo and to the larger surface of bamboo poles that facilitate fish grazing and periphyton dislodgment that in turn have a renewal effect on periphyton. Stocking bottom feeding fish produces a fertilizing effect through the food web that benefits the filter-feeding fish and that makes it unnecessary to increase the dose of inorganic and organic fertilizers applied to the ponds. Thus, the output of this analysis will help the fish farmers in resource constrained countries to improve their production in periphyton-based ponds just by choosing bamboo substrates, stocking a bottom feeder fish together with the filter feeders, and saving money on fertilizers. 相似文献
34.
Predicting gene expression from sequence 总被引:36,自引:0,他引:36
35.
Nicky Spence Nancy C.L. Rodrigues Polykarpos Angelos Nomikos Khalid Mohammed Yaseen Mansour Abdullah Alshehri 《Journal of musculoskeletal & neuronal interactions》2020,20(4):480
Objectives:The purpose of this study is to establish whether physiotherapists’ ratings are consistent, when using the Action Research Arm Test (ARAT) to score a chronic stroke patient.Methods:This was part of a large project establishing the reliability in chronic stroke. This study used a correlational design comparing the association between physiotherapist scores of the same patient, to establish the ARAT’s inter-rater reliability. The COSMIN checklist was followed to enhance the methodology of the study.Results:Twenty physiotherapists (8 female and 12 male) aged between 25 and 53 years were selected. There were no participant dropouts or withdrawals. The sample size was normally distributed. The physiotherapists appeared representative of the UK physiotherapy population, with the exception of gender. The distribution of scores showed a normal distribution with standard deviation of score of 1.9. The Kendall’s W test showed 0.711 of agreement between the raters. The scores achieved statistical significance showing consistency between physiotherapists’ scores with chronic stroke. Limitations of the study were the use of a small single center convenience sample that may reduce the generalizability of the findings.Conclusions:The ARAT is consistent when scored by physiotherapists in a chronic stroke population. The inter-rater reliability range was (0.70 to 0.90) which is categorized as good. 相似文献
36.
Asha Thomas Georgia D. Tourassi Adel S. Elmaghraby Roland Valdes Jr. Saeed A. Jortani 《Clinical proteomics》2006,2(1-2):13-32
Data mining application to proteomic data from mass spectrometry has gained much interest in recent years. Advances made in proteomics and mass spectrometry have resulted in considerable amount of data that cannot be easily visualized or interpreted. Mass spectral proteomic datasets are typically high dimensional but with small sample size. Consequently, advanced artificial intelligence and machine learning algorithms are increasingly being used for knowledge discovery from such datasets. Their overall goal is to extract useful information that leads to the identification of protein biomarker candidates. Such biomarkers could potentially have diagnostic value as tools for early detection, diagnosis, and prognosis of many diseases. The purpose of this review is to focus on the current trends in mining mass spectral proteomic data. Special emphasis is placed on the critical steps involved in the analysis of surface-enhanced laser desorption/ionization mass spectrometry proteomic data. Examples are drawn from previously published studies and relevant data mining terminology and techniques are exlained. 相似文献
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