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261.
We propose a novel hierarchical hidden Markov regression model for determining gene regulatory networks from genomic sequence and temporally collected gene expression microarray data. The statistical challenge is to simultaneously determine the groupings of genes and subsets of motifs involved in their regulation, when the groupings may vary over time, and a large number of potential regulators are available. We devise a hybrid Monte Carlo methodology to estimate parameters under 2 classes of latent structure, one arising due to the unobservable state identity of genes and the other due to the unknown set of covariates influencing the response within a state. The effectiveness of this method is demonstrated through a simulation study and an application on an yeast cell-cycle data set. 相似文献
262.
Al-Masoudi NA Al-Soud YA Ali IA Schuppler T Pannecouque C De Clercq E 《Nucleosides, nucleotides & nucleic acids》2007,26(3):223-230
New derivatives of azidothymidine (AZT) substituted by alkyl and alkylsulphonyl groups at N-3 and C-5', respectively, have been synthesized. The new synthesized derivatives showed remarkable anti-HIV-1 and HIV-2 activity in MT-4 cells. Compounds 8 and 10 have IC(50) values of 0.83 and 0.31 microg/mL against HIV-1 with therapeutic index of 83 and 403, respectively, and IC(50) values of 0.93 and 0.29 microg/mL against HIV-2 with therapeutic index of 74 and 431, respectively. This means that compounds 8 and 10 were cytotoxic to MT-4 cells at CC(50) of 69.2 microg/mL and 125 microg/mL, respectively. 相似文献
263.
A series of 1,3-diaryl-5-(2,3,5-tri-O-benzoyl-beta-D-ribofuranosyl)-1H-1,2,4-triazole nucleosides (3a-f) were synthesized via the intermolecular cyclization of hydrazonyl chlorides with peracylated ribofuranosyl cyanide catalyzed by Yb(OTf)3 or AgNO3, respectively. Similarly, the 1,2,4-triazole of glucopyranosyl C-nucleosides 5a,b were prepared from the hydrazonyl chlorides and the nitrile 4. Alternatively, the 1,2,4-triazole N-nucleoside 8 was obtained from cyclization of the unsymmetrical bis[alpha-(4-methoxyphenyl)aminobenzylidene]-hydrazine with peracylated 1-amino-D-manno-pentitol. 相似文献
264.
Rohini Bhat Anil Kumar Singh Muntazir Mushtaq Romesh Kumar Salgotra Manmohan Sharma Basharat Ahmad Bhat Umer Basu Ibrahim Al-Ashkar Mohammad Anwar Hossain Akihiro Ueda Ayman El Sabagh 《Phyton》2022,91(11):2439-2459
Identification of quantitative trait loci (QTLs) controlling yield and yield-related traits in rice was performed in
the F2 mapping population derived from parental rice genotypes DHMAS and K343. A total of 30 QTLs governing nine different traits were identified using the composite interval mapping (CIM) method. Four QTLs were
mapped for number of tillers per plant on chromosomes 1 (2 QTLs), 2 and 3; three QTLs for panicle number
per plant on chromosomes 1 (2 QTLs) and 3; four QTLs for plant height on chromosomes 2, 4, 5 and 6; one
QTL for spikelet density on chromosome 5; four QTLs for spikelet fertility percentage (SFP) on chromosomes
2, 3 and 5 (2 QTLs); two QTLs for grain length on chromosomes 1 and 8; three QTLs for grain width on chromosomes1, 3 and 8; three QTLs for 1000-grain weight (TGW) on chromosomes 1, 4 and 8 and six QTLs for yield
per plant (YPP) on chromosomes 2 (3 QTLs), 4, 6 and 8. Most of the QTLs were detected on chromosome 2, so
further studies on chromosome 2 could help unlock some new chapters of QTL for this cross of rice variety. Identified QTLs elucidating high phenotypic variance can be used for marker-assisted selection (MAS) breeding.
Further, the exploitation of information regarding molecular markers tightly linked to QTLs governing these traits
will facilitate future crop improvement strategies in rice. 相似文献
265.
Hassan Mona M. Taha Rania A. Abd El-Aziz M. E. Shaaban Esam A. Ibrahim Eman A. 《Plant Cell, Tissue and Organ Culture》2022,148(1):73-80
Plant Cell, Tissue and Organ Culture (PCTOC) - Leaf chlorosis is often a problem in micropropagated Rubus idaeus, which makes successful acclimatization difficult. We found that... 相似文献
266.
Baioumy Asmaa Ali Swelim Hamdy Hamed Ibrahim Ahmed Adly Mohamed Fatma El‑Sayed Marzouk Aleya Soliman El‑Alfy Sherif Helmy 《Experimental & applied acarology》2022,86(4):609-610
Experimental and Applied Acarology - 相似文献
267.
Sapey Enoch Jiang Bingjun Liu Luping Yuan Shan Wu Tingting Ibrahim Seifeldin Elrayah Sun Shi Yue Yanlei Han Tianfu 《Plant Molecular Biology Reporter》2022,40(3):433-445
Plant Molecular Biology Reporter - The j allele delays flowering and enhances yield of long juvenile (LJ) soybean under short day (SD) condition. However, the underlying mechanism of j in flowering... 相似文献
268.
Gharbi Dorra Mobayed Hassan M. Ali Ramzy Mohammed Tuffaha Amjad Dason Blessing Reena Ibrahim Tayseer Adeli Mehdi Sattar Hisham A. Trigo Maria del Mar Al-Nesf Maryam Ali 《Aerobiologia》2022,38(3):329-342
Aerobiologia - Daily monitoring of airborne fungal spores was carried out for the first time in Al Khor city, Qatar, using a Hirst type 7-day recording volumetric spore trap, from May 2017 to May... 相似文献
269.
270.
Jordi Toda Avelino Corma Raed H. Abudawoud Mohamed S. Elanany Ibrahim M. Al-Zahrani 《Molecular simulation》2015,41(16-17):1438-1448
A molecular dynamics study of diffusion of p-xylene and o-xylene has been performed over three different pure silica 10-ring zeolites, MFI, SFG and TUN. The shape selective properties of the frameworks of these three materials have been tested using four different types of force fields commonly used based on united atom, rigid-ion and core-shell approximations. The performance of each force field is analysed in order to find which force fields can give sufficiently accurate estimations that allow to select appropriate zeolites for selective separation of para/ortho xylene. This performance was found to depend on the quality of the structural properties of the zeolite, in particular the size and shape of the 10 rings which act as bottlenecks for the diffusion. The computational results allow us to define some optimum characteristics for the selective diffusion of p-xylene. 相似文献