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141.
Mona Fathy Manal Kamal Marwa Al-Sharkawy Hanaa Al-Karaksy Nora Hassan 《Biomarkers》2016,21(7):573-577
Aim of work: To estimate the frequency of mutations involving exons 6, 8 and 9 of Adenosine triphosphate-binding cassette, subfamily B, member 4 (ABCB4) gene among children with progressive intrahepatic cholestasis with high γ-GT activity (PFIC3).Subjects and methods: Cross sectional study was conducted on 30 children with PFIC3. Genotyping was performed by sequencing analysis of exons 6, 8 and exon 9 of ABCB4 gene.Results: Heterozygous synonymous polymorphic variant was detected in exon 6 (rs 1202283) and in exon 8 (rs 2109505). No mutations in studied exons were detected.Conclusion: Exons 6, 8 and 9 mutations of ABCB4 gene are not common among Egyptian children with PFIC3. 相似文献
142.
Photophysical properties of hydroxyphenyl benzazoles and their applications as fluorescent probes to study local environment in DNA,protein and lipid 下载免费PDF全文
Fluorescence techniques have drawn increasing attention because they provide crucial information about molecular interactions in protein–ligand systems beyond that obtained by other methods. The advantage of fluorescence spectroscopy stems from the fact that the majority of molecules in biological systems do not exhibit fluorescence, making fluorescent probes useful with high sensitivity. Also, the fluorescence emission is highly sensitive to the local environment, providing a valuable tool to investigate the nature of binding sites in macromolecules. In this review, we discuss some of the important applications of a class of molecules that have been used as fluorescent probes in a variety of studies. Hydroxyphenyl benzazoles (HBXs) show distinct spectroscopic features that make them suitable probes for the study of certain biological mechanisms in DNA, protein and lipid. In particular, the complex photophysics of 2‐(2′‐hydroxyphenyl)benzoxazole (HBO) and the distinguished fluorescence signatures of its different tautomeric forms make this molecule a useful probe in several applications. Among these are probing the DNA local environment, study of the flexibility and specificity of protein‐binding sites, and detecting the heterogeneity and ionization ability of the head groups of different lipidic phases. The spectroscopy of HBX molecules and some of their chemically modified structures is also reviewed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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145.
Rania A. Taha Mona M. Hassan Eman A. Ibrahim Nesreen H. Abou Baker Esam A. Shaaban 《Plant Cell, Tissue and Organ Culture》2016,127(2):525-534
Among the recent line of technological innovations, nanotechnology takes a promising position in agriculture and food production. Nanotechnology permits definite advances in agricultural research, such as reproductive science and technology. This investigation is interested in studying the in vitro effect of carbon nanotubes (CNTs) on callus, embryogenesis, embryo germination and elongation as well as rooting stage of date palm. Carbon nanotubes concentrations were investigated as 0.0, 0.05 and 0.1 mg/l. Results showed that CNTs affect all stages of micropropagation of date palm. Callus fresh weight showed the optimum value at 0.05 mg/l. In embryogenesis stage, CNTs decreased the number of embryos compared with the control while, increased number of germinated embryos and root number. Carbon nanotubes gave a significant enhancement for shoot length and leaf number in elongation stage. Similarly, it enhanced root number, root length, plantlet length and hairy roots. Chemical analysis as chlorophyll a, b, carotenoids, flavonoids, antioxidant enzymes and nutrients concentration and uptake were determined. 相似文献
146.
Effect of Absence of Ciliate Protozoa From the Rumen on Microbial Activity and Growth of Lambs 总被引:8,自引:7,他引:1 下载免费PDF全文
A survey of the components of the rumen ciliate population in a series of adult sheep, raised in the Faculty of Agriculture, University of Alexandria, has shown that a mixture of Entodinium, Isotricha, Ophryoscolex, Diplodinium, and Polyplastron species was found in the rumen contents of Egyptian sheep; no Epidinium and a negligible number of Dasytricha ruminantium were also observed. The microbial population, reducing sugars, ammonia, volatile fatty acids (VFA) production, and growth rate of 14 lambs inoculated with whole rumen contents from a mature sheep were compared over a 6-month period with those of 13 lambs maintained under the same conditions, except that they were strictly isolated from other ruminants. Certain large oval organisms and large numbers of flagellates and Oscillospira were frequently observed in the rumen contents of the isolated lambs. The reducing sugars, ammonia, and VFA levels, measured before and at intervals after feeding, in the inoculated lambs showed a pronounced rise above the values found in the ciliate-free animals. The propionic acid-acetic acid ratio in the rumen contents of the faunated lambs was considerably higher than in the nonfaunated controls. The inoculated lambs grew faster than the isolated lambs. Differences in weight gain which ranged from 15 to 17% were statistically significant. The inoculated animals impressed the observers by their good appearance which was superior to that of the ciliate-free lambs. It was, therefore, concluded that the rumen ciliate protozoa are essential for the metabolism and growth of young lambs. 相似文献
147.
Effect of some arsenic antagonists on the toxicity, distribution and excretion of arsenite and arsenate in rats. 总被引:1,自引:0,他引:1
A M Hilmy N A el-Domiaty M A Kamal M A Mohamed W E Abou Samra 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1991,99(3):357-362
1. Arsenite and arsenate poisoned rats were treated with either BAL (2,3-dimercapto-1-propanol), penicillamine (PA) (beta-beta dimethyl cystein) or selenium (Se) (as sodium selenite). 2. The minimal dose of each antagonist that treated arsenic-induced lethality (causing 100% survival) was the same for both arsenite and arsenate. 3. Arsenic mobilization from the tissues (blood, kidney, liver, lungs, spleen, muscles, brain, heart) and its excretion in urine and feces were higher in arsenite-intoxicated animals than in arsenate-intoxicated ones. 4. The effect of each antagonist, when injected alone, on the urinary and fecal excretion of endogenous metals (Cu, Zn, Fe, Ca and Mg) was also examined. 5. The results indicated marked differences in the relative ability of BAL, PA and Se to increase the excretion of the metals. 相似文献
148.
Drought stress (DS) is one of the most critical environmental abiotic stresses for wheat production in the arid environments. Selection of high-yielding genotypes tolerant to DS can play a significant role in mitigation the negative impacts associated with DS. In the present study, generation means analysis (GMA) was used to study the performance of two crosses under well irrigation (WI) and deficit irrigation [cross I (Line 44 × Shandweel-1) and cross II (Line 20 × Sakha 93)]. Significant differences were observed for days to heading (DH), days to maturity (DM), plant height (PH), spike length (SL), number of spikes per plant (NS/P), number of grains per spike (NG/S), thousand-grain weight (TGW), grain yield per plant (GY/P), and proline content (PC) in the six populations of the two crosses within each irrigation level. Cross II had early maturity and the highest PC, NS/P, TGW, and GY/P regardless of the irrigation level. Cross I showed positive significant relative heterosis and heterobeltiosis for GY/P under the two irrigation levels. The inheritance of characters of cross I revealed additive, dominant, and epistatic effects, which varied with trait and stress. Additive genetic effects predominated in DH, SL, and PC, while non- additive were found in DM, NS/P, NG/S, and GY/P. Narrow-sense heritability estimates (h2n) were high for DH and PC, moderate to high for PH and SL, moderate for DM, NG/S, NS/P, and TGW, and low for GY/P. Based on different drought indices the populations BC1, BC2, F1, and P1 of cross II and BC1 of cross I were more tolerant to drought stress. Therefore, PC, TGW and DH can be used as selection indicators to improve wheat for drought tolerance in early generations and other yield components traits in late generations. The second cross (Line 20 × Sakha 93) shows promise and is of interest to a drought tolerance breeding program, where wheat breeders can use recombinant breeding strategies to construct desirable drought stress genes. Correlation and path coefficient revealed that TGW and PC were the main contributor in grain yield in both environments. 相似文献
149.
Marwa Badr Hebatallah Said Manal L. Louka Hesham A. Elghazaly Ahmed Gaballah Mai Atef Abd El Mageed 《Journal of cellular biochemistry》2019,120(3):3459-3466
Breast cancer is the second most common cancer diagnosed worldwide. Human epidermal growth factor receptor 2 (HER2)-positive breast cancer represents about 20% to 30% of all breast cancers. Trastuzumab is used in the treatment of HER2-positive breast cancer. MicroRNA-21 (miR-21) is an oncomiR that acts by inhibiting many tumor-suppressor genes. We analyzed the relative expression levels of serum miR-21 in 20 HER2-positive metastatic breast cancer patients before and after 3 months of treatment with trastuzumab. miR-21 levels decreased with a high significant difference after trastuzumab therapy (P = 0.001). Although miR-21 expression levels were lower in responders than in nonresponders, the difference was not statistically significant ( P = 0.6). Our results demonstrated a significant negative correlation between its basal expression, expression levels after treatment, and time to progression ( P = 0.03 and 0.01, respectively). These results make miR-21 a potential prognostic factor for HER2-positive metastatic breast cancer patients. Additionally, it can be an interesting potential target in therapy using antisense oligonucleotides for miR-21. 相似文献
150.
Studies of hemoglobin types in the population of Lebanon 总被引:1,自引:0,他引:1
R Cabannes N Taleb F Ghorra A Schmitt-Beurrier 《Nouvelle revue francaise d'hematologie》1965,5(6):851-856