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991.
Ericifolin, an eugenol 5-O-beta-(6'-O-galloylglucopyranoside) possessing the naturally unknown phenolic moiety, 5-hydroxyeugenol, together with the two new phenolics, 2-O-p-hydroxybenzoyl-6-O-galloyl-(alpha/beta)-4C1-glucopyranose and 3-methoxyellagic acid 4-O-rhamnopyranoside have been isolated from the antibacterial leaves extract of Melaleuca ericifolia. In addition, 19 known phenolics were also separated and characterized. All structures were elucidated on the basis of analysis of 1H, 13C NMR, HMQC, HMBC and FTMS spectral data.  相似文献   
992.
Forty faba bean (Vicia faba L.) genotypes were evaluated for their agro-morphological performance and molecular diversity under Central Region of Saudi Arabia conditions during 2010–11 and 2011–12 seasons. Field performance results showed that faba genotypes exhibited a significant amount of variation for their agro-morphological studied parameters. Giza40 recorded the tallest genotype (139.5 cm), highest number of seeds per plants (100.8), and the highest seed yield per plant (70.8 g). The best performing genotypes were Giza40, FLIP03-014FB, Gazira1 and Goff1. Genetic variability among genotypes was determined using Sequence Related Amplified Polymorphism (SRAP) and Amplified Fragment Length Polymorphism (AFLP) markers. A total of 183 amplified fragments (alleles) and 1758 polymorphic fragments (bands) in SRAP and 202 alleles and 716 bands in AFLP were obtained using six SRAP and four AFLP primer combinations respectively. Polymorphism information content (PIC) values for AFLP and SRAP markers were higher than 0.8, indicating the existence of a considerable amount of genetic diversity among faba tested genotypes. The UPGMA based clustering of faba genotypes was largely based on origin and/or genetic background. Result of cluster analysis based on SRAP showed weak and not significant correlation while, it was highly significant based on AFLP analysis with agro-morphological characters (r = 0.01, p > 0.54 and r = 0.26, p < 0.004 respectively). Combined SRAP and AFLP markers proved to be significantly useful for genetic diversity assessment at molecular level. They exhibited high discrimination power, and were able to distinguish the faba bean genotypes with high efficiency and accuracy levels.  相似文献   
993.
The present study aimed to analyse the level of genetic variation in the eastern Central European (Slovenia, Hungary, and Romania/Transylvania) populations of the Large Blues ( Maculinea ) to analyse the pattern of differentiation both between and within the species. One objective was to compare the level of differentiation between the two disputed species ( Maculinea alcon and Maculinea rebeli ) with that among the other species. Imagos were collected from 23 localities in eastern Central Europe in 2002. Enzyme polymorphism was analysed using polyacrylamide gel electrophoresis. Fourteen enzyme loci were studied in all samples. In the analysis of the data, F -statistics and Nei's genetic distances were calculated and a dendrogram (unweighted pair group method with arithmetic mean) was constructed on the basis of the distance matrix. A multivariate analysis of variance was performed to study the pattern of genetic differentiation among the samples. Principal component analysis analysis was also carried out using the allele frequency data of the samples. Our results indicated that the large blues are generally less polymorphic than other European lycaenid butterflies studied. At the same time, the level of genetic differentiation was high, even among local populations within the species. A low level of genetic variation within the populations coupled with strong differentiation among them implies the effect of genetic drift. Strong genetic differentiation of four Maculinea species ( M. alcon , Maculinea teleius, Maculinea nausithous , and Maculinea arion ) was confirmed. Significant differentiation was not found between M. alcon and M. rebeli .  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 11–21.  相似文献   
994.
The effects of Ca2+ and temperature on the K+ contents of root segments of wheat (Triticum aestivum L. cv. Aurora), rice (Oryza sativa L. cv. Dunghan Shali) and cucumber (Cucumis sativus L. cv. Csemege Fürtös) were investigated with special regard to the low-temperature anomaly of the K+ uptake of thermophilic plants. The anomaly occurred in those root segments where the K+ contents turned out to be highest. The K+ contents of the apical root sections of thermophilic species responded in general to Ca2+ in more pronounced ways than those of wheat, at both 0 and 25°C. The concerted actions of a purely physical process with negative temperature coefficient and of the special thermotropic properties of the membranes are suggested to be responsible for the low-temperature anomaly. A strict discrimination between the Viets-effect on the content (classical Viets-effect) and on the uptake is proposed. The classical Viets-effect seems to be related to alterations in both active transport and exchange processes.  相似文献   
995.
Mosaicism is present in more than 50% of the cases with small supernumerary marker chromosomes (sSMCs) and karyotype 47,XX,+mar/46,XX or 47,XY,+mar/46,XY. Recently we provided first evidence that the mitotic stability of sSMC is dependent on their structure, i.e. their shape. Thus, here we performed a long term in vitro study on 12 selected cell lines from the Else Kröner–Fresenius-sSMC-cellbank (http://ssmc-tl.com/ekf-cellbank.html) to test mitotic sSMC stability systematically. The obtained results showed that inverted duplicated shaped and also the so-called complex sSMCs (group 1) are by far more stable, than centric-minute- or ring-shaped sSMCs (groups 2). Generally speaking, the percentage of cells with group-1-sSMCs remained stable over 90 days of cell culture, while that of group-2-sSMCs in parts dramatically decreased. In one group-2-cell line the sSMC was even lost completely after 30 days of in vitro culture, in others the sSMC was depleted in up to 40% of the cells. Still the highest rate of sSMC loss was recorded during EBV-transformation. Overall, the major difference between groups 1 and 2 was the number of telomeres per sSMC. In group 1 the sSMCs had “original” telomeres at both of their ends; in group 2 the sSMCs had either no, possibly secondary acquired and/or only one original telomere. This absence of protective telomeric sequences in group 2 seems to make sSMC more susceptible for loss during cell division. Still, also a growth advantage of cells without sSMC cannot be neglected entirely.  相似文献   
996.
Abstract: An assassin bug, Sycanus leucomesus Walk. (Hem., Reduviidae) fed on nuclear polyhedrosis virus (NPV)-infected larvae of Spodoptera litura Fabr. (Lep., Noctuidae) inflicted variable effect on its developmental biology. The impact varied with the duration the predators were exposed. The predators that were fed infected prey throughout their lives appeared normal but they had significantly smaller sizes of head capsules and shorter tibial lengths than those fed healthy prey. These individuals had their overall pre-imaginal survival rate reduced by 10% from 91.25 to 81.25%, pre-oviposition period prolonged to more than 12 days, longevity reduced by 10 and 19 days in the males and females, respectively, and fecundity reduced to 41%. Even though ingestion of NPV could adversely influence their biology, the predators could serve as disseminators of the pathogen. The predators defecated infective viral polyhedral inclusion bodies (PIBs) ranging from 1.22 to 1.60 × 1010/deposit with an average of 1.42 × 1010. This NPV, when fed to its original host, caused 97% larval mortality within 10 days. Thus in nature, S. leucomesus may suppress the pest population not only by predation but also by dispersing the pathogen.  相似文献   
997.

Background  

Low concentrations of carbon monoxide (CO) protect hepatocytes against apoptosis and confers cytoprotection in several models of liver. Mitochondria are key organelles in cell death control via their membrane permeabilization and the release of pro-apoptotic factors.  相似文献   
998.
999.
This study aims at identifying common pathogenic somatic mutations at different stages of colorectal carcinogenesis in Egyptian patients. Our cohort included colonoscopic biopsies collected from 120 patients: 20 biopsies from patients with inflammatory bowel disease, 38 from colonic polyp patients, and 62 from patients with colorectal cancer. On top of this, the cohort included 20 biopsies from patients with non-specific mild to moderated colitis. Targeted DNA sequencing using a customized gene panel of 96 colorectal related genes running on the Ion Torrent NGS technology was used to process the samples. Our results revealed that 69% of all cases harbored at least one somatic mutation. Fifty-seven genes were found to carry 232 somatic non-synonymous variants. The most frequently pathogenic somatic mutations were localized in TP53, APC, KRAS, and PIK3CA. In total, 16 somatic mutations were detected in the CRC group and in either the IBD or CP group. In addition, our data showed that 51% of total somatic variants were CRC-specific variants. The average number of CRC-specific variants per sample is 2.4. The top genes carrying CRC-specific mutations are APC, TP53, PIK3CA, FBXW7, ATM, and SMAD4. It seems obvious that TP53 and APC genes were the most affected genes with somatic mutations in all groups. Of interest, 85% and 28% of the APC and TP53 deleterious somatic mutations were located in Exon 14 and Exon 3, respectively. Besides, 37% and 28% of the total somatic mutations identified in APC and TP53 were CRC-specific variants, respectively. Moreover, we identified that, in 29 somatic mutations in 21 genes, their association with CRC patients was unprecedented. Ten detected variants were likely to be novel: six in PIK3CA and four variants in FBXW7. The detected P53, Wnt/βcatenin, Angiogenesis, EGFR, TGF-β and Interleukin signaling pathways were the most altered pathways in 22%, 16%, 12%, 10%, 9% and 9% of the CRC patients, respectively. These results would contribute to a better understanding of the colorectal cancer and in introducing personalized therapies for Egyptian CRC patients.  相似文献   
1000.
A library of 17 nanoparticles made of acrylate and methacrylate copolymers is prepared, characterized, and screened against six epitopes of adeno‐associated viruses (AAV)‐neutralizing antibodies to assess their affinity and specificity. Peptide epitopes are immobilized onto the surface of glass beads, packed in filtration microplates, and incubated with fluorescein‐labelled nanoparticles. Following intense washing, the affinity of nanoparticles to immobilized epitopes is assessed by measuring the fluorescence of captured nanoparticles. The results show that polar monomers, acrylic acid in particular, have a positive impact on polymer affinity towards all peptides used in this study. The presence of hydrophobic monomers, on other hand, has a negative impact on polymer binding. The composition of peptides used in this study has no noticeable impact on the affinity of synthesized nanoparticles. The affinity of nanoparticles with the highest affinity to peptide targets does not exceed millimolar level. Overall, it is found that the synthesized library showed modest affinity but lacked specificity, which should be further “tuned,” for example, by using molecular imprinting to achieve an acceptable level of affinity and specificity for practical application.  相似文献   
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