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951.
Nasr Fahd A. Shahat Abdelaaty A. Alqahtani Ali S. Ahmed Mohammad Z. Qamar Wajhul Al-Mishari Abdullah A. Almoqbil Abdulaziz N. 《Molecular biology reports》2020,47(8):6043-6051
Molecular Biology Reports - Centaurea bruguierana, of the Asteraceae family, has a long history of use in traditional medicines for the treatment of various ailments. However, the anticancer... 相似文献
952.
Amdoun Ryad Sahli Fatiha Hamadache Kamel Ouzzane Abdel-Hakim Khelifi-Slaoui Majda Moustafa Khaled Hefferon Kathleen Makhzoum Abdullah Khelifi Lakhdar 《Plant Cell, Tissue and Organ Culture》2020,141(1):41-53
Plant Cell, Tissue and Organ Culture (PCTOC) - Polyethylene glycol (PEG)-mediated transient expression system in plant protoplasts has been widely used in a variety of plants for gene function... 相似文献
953.
Rémy Crassard Michael D. Petraglia Adrian G. Parker Ash Parton Richard G. Roberts Zenobia Jacobs Abdullah Alsharekh Abdulaziz Al-Omari Paul Breeze Nick A. Drake Huw S. Groucutt Richard Jennings Emmanuelle Régagnon Ceri Shipton 《PloS one》2013,8(7)
Pre-Pottery Neolithic assemblages are best known from the fertile areas of the Mediterranean Levant. The archaeological site of Jebel Qattar 101 (JQ-101), at Jubbah in the southern part of the Nefud Desert of northern Saudi Arabia, contains a large collection of stone tools, adjacent to an Early Holocene palaeolake. The stone tool assemblage contains lithic types, including El-Khiam and Helwan projectile points, which are similar to those recorded in Pre-Pottery Neolithic A and Pre-Pottery Neolithic B assemblages in the Fertile Crescent. Jebel Qattar lies ∼500 kilometres outside the previously identified geographic range of Pre-Pottery Neolithic cultures. Technological analysis of the typologically diagnostic Jebel Qattar 101 projectile points indicates a unique strategy to manufacture the final forms, thereby raising the possibility of either direct migration of Levantine groups or the acculturation of mobile communities in Arabia. The discovery of the Early Holocene site of Jebel Qattar suggests that our view of the geographic distribution and character of Pre-Pottery Neolithic cultures may be in need of revision. 相似文献
954.
955.
Abdullah Hijazi 《Nucleosides, nucleotides & nucleic acids》2013,32(4):537-547
Abstract The synthesis of 2-Methylthio-1-(β-D-ribofuranosyl) naphthimidazole has been accomplished by condensation of 2-methylthio-1-trimethylsilylnaphthimidazole(3) with 1-O-acetyl-2,3,5-tri-O-benzoyl-β-D-ribofuranose(4) in the presence of trimethylsilyl triflate in 1,2-dichloroethane, followed by subsequent debenzoylation. Structural proofs are based on elementary analysis, UV- and 1H-NMR-spectra. 相似文献
956.
Selvi Y Smolensky MH Boysan M Aydin A Besiroglu L Atli A Gumrukcuoglu HA 《Chronobiology international》2011,28(4):371-377
Population-based studies indicate the risk of acute myocardial infarction (AMI) is greatest in the morning, during the initial hours of diurnal activity. The aim of this pilot study was to determine whether chronotype, i.e., morningness and eveningness, impacts AMI onset time. The sample comprised 63 morning- and 40 evening-type patients who were classified by the Horne-?stberg Morningness-Eveningness Questionnaire (MEQ) in the hospital after experiencing the AMI. The average wake-up and bed times of morning types were ~2?h earlier than evening types. Although the lag in time between waking up from nighttime sleep and AMI onset during the day did not differ between the two chronotypes, the actual clock-hour time of the peak in the 24-h AMI pattern did. The peak in AMI of morning types occurred between 06:01 and 12:00?h and that of the evening types between 12:01 and 18:00?h. Although the results of this small sample pilot study suggest one's chronotype influences the clock time of AMI onset, larger scale studies, which also include assessment of 24-h patterning of events in neither types, must be conducted before concluding the potential influence of chronotype on the timing of AMI onset. 相似文献
957.
Pathway analysis has lead to a new era in genomic research by providing further biological process information compared to traditional single gene analysis. Beside the advantage, pathway analysis provides some challenges to the researchers, one of which is the quality of pathway data itself. The pathway data usually defined from biological context free, when it comes to a specific biological context (e.g. lung cancer disease), typically only several genes within pathways are responsible for the corresponding cellular process. It also can be that some pathways may be included with uninformative genes or perhaps informative genes were excluded. Moreover, many algorithms in pathway analysis neglect these limitations by treating all the genes within pathways as significant. In previous study, a hybrid of support vector machines and smoothly clipped absolute deviation with groups-specific tuning parameters (gSVM-SCAD) was proposed in order to identify and select the informative genes before the pathway evaluation process. However, gSVM-SCAD had showed a limitation in terms of the performance of classification accuracy. In order to deal with this limitation, we made an enhancement to the tuning parameter method for gSVM-SCAD by applying the B-Type generalized approximate cross validation (BGACV). Experimental analyses using one simulated data and two gene expression data have shown that the proposed method obtains significant results in identifying biologically significant genes and pathways, and in classification accuracy. 相似文献
958.
BACKGROUND AND AIMS:
Saudi Arabia falls in the high prevalent zone of αα and β thalassemias. Early screening for the type of thalassemia is essential for further investigations and management. The study was carried out to differentiate the type of thalassemia based on red cell indices and other hematological parameters.MATERIALS AND METHODS:
The study was carried out on 991 clinically suspected cases of thalassemias in Riyadh, Saudi Arabia. The hematological parameters were studied on Coulter STKS. Cellulose acetate hemoglobin electrophoresis and high-performance liquid chromatography (HPLC) were performed on all the blood samples. Gene deletion studies were carried out by restriction fragment length polymorphism (RFLP) technique using the restriction endonucleases Bam HI.STATISTICAL ANALYSIS:
Statistical analysis was performed on SPSS 11.5 version.RESULTS:
The hemoglobin electrophoresis and gene studies revealed that there were 406 (40.96%) and 59 (5.95 %) cases of β thalassemia trait and β thalassemia major respectively including adults and children. 426 cases of various deletion forms of α thalassemias were seen. Microcytosis was a common feature in β thalassemias trait and (-α/-α) and (--/αα) types of α thalassemias. MCH was a more significant distinguishing feature among thalassemias. β thalassemia major and α thalassemia (-α/αα) had almost normal hematological parameters.CONCLUSION:
MCV and RBC counts are not statistically significant features for discriminating between α and β thalassemias. There is need for development of a discrimination index to differentiate between α and β thalassemias traits on the lines of discriminatory Indices available for distinguishing β thalassemias trait from iron deficiency anemia. 相似文献959.
Diversity of bovine rumen methanogens In vitro in the presence of condensed tannins, as determined by sequence analysis of 16S rRNA gene library 总被引:1,自引:0,他引:1
Tan HY Sieo CC Lee CM Abdullah N Liang JB Ho YW 《Journal of microbiology (Seoul, Korea)》2011,49(3):492-498
Molecular diversity of rumen archaeal populations from bovine rumen fluid incubated with or without condensed tannins was
investigated using 16S rRNA gene libraries. The predominant order of rumen archaea in the 16S rRNA gene libraries of the control
and condensed tannins treatment was found to belong to a novel group of rumen archaea that is distantly related to the order
Thermoplasmatales, with 59.5% (15 phylotypes) and 81.43% (21 phylotypes) of the total clones from the control and treatment clone libraries,
respectively. The 16S rRNA gene library of the control was found to have higher proportions of methanogens from the orders
Methanomicrobiales (32%) and Methanobacteriales (8.5%) as compared to those found in the condensed tannins treatment clone library in both orders (16.88% and 1.68% respectively).
The phylotype distributed in the order Methanosarcinales was only found in the control clone library. The study indicated that condensed tannins could alter the diversity of bovine
rumen methanogens. 相似文献