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691.
Nemat M. Hassan Ahmed K. A. El-Sayed Heba T. Ebeid Mamdouh M. Nemat Alla 《Acta Physiologiae Plantarum》2011,33(2):593-600
Sunflower (Helianthus annuus L.) hybrid Hysun 333 (black seeded) was cultivated in a greenhouse and subjected during flowering stage to drought with or
without the application of boron (B) and calcium (Ca) foliar sprays alone or in combination. The results revealed that drought
induced a sharp decrease in seed fresh weight, seed protein and lipid contents. Application of B and Ca combined sprays overcame
the drought effects on seed weight and seed lipid contents. Catalase expression was detected as a single band for all treatments
where peroxidase isozymes were increased to seven, six of them were expressed when B sprays were applied with drought indicating
that B has a major role in peroxidase up-regulation under drought conditions. SDS-PAGE analysis showed differential changes
in protein profile with an appearance and/or disappearance of polypeptide protein bands, some of which were concluded to be
drought-related proteins. The combined sprays of B and Ca seemed to overcome the effects of drought through minimizing band
alterations (disappearance and/or appearance). The DD-RT PCR showed a variation in gene expression between the control and
the other treatments. Sprays of B and Ca in combination seemed to be the most effective in band up-regulation and/or down-regulation
that might play a possible role in improving tolerance of sunflower to overcome the drought deleterious effects. 相似文献
692.
Bronwen W. Cribb Jim Hanan Myron P. Zalucki Lynda E. Perkins 《Arthropod-Plant Interactions》2010,4(3):165-173
Locomotory behaviour of 1st instar Helicoverpa armigera is influenced by a complex of micro-attributes, the leaf “environment”, comprising odours, wax chemistry, trichomes and grip
texture. Larval movement speeds on leaves of different types varied more than eight fold. On garden pea, Pisum sativum, there is a hierarchy of stimuli perceived by larvae resulting in differing behavioural responses. Light and angle are paramount
in responses to micro-environment. These influence responses to local stimuli. Experiments in darkness produce different responses
from those under laboratory light. In darkness, on horizontal surfaces as found for most leaves, preference for leaf surface
is driven by micro-environment associated with leaf waxes. Larvae prefer the abaxial surface. In light, on horizontal surfaces,
larvae seek enclosed spaces and foray under leaf surfaces. They wander more openly in the dark. Such information is important
in building a model of larval behaviour and predicting behaviour on differing plant architectures. 相似文献
693.
H. G. Hanan 《BMJ (Clinical research ed.)》1941,1(4194):794-795
694.
The head kidneys of adult Periophthalamus koelreuteri contain many functional glomerular nephorns which on the basis of this histochemical study, are indistinguishable from those of the typical opistonephros of marine teleosts. The anterior lobes resemble, in location and in the presence of intertubular erythropoeitic tissue, the pronephros in other species. The single nephron found there, however, does not differ significantly from the other nephrons of the head kidney. It is suggested, therefore, that the nephrons of the head kidney in this species are opisthonephric in origin. 相似文献
695.
Naeem M. Eesa Hanaa El-Sherif Wael M. El-Sayed 《Invertebrate reproduction & development.》2017,61(1):27-33
The sensitivity of Spodoptera littoralis second and fourth instar larvae to the heavy metals cadmium (Cd) and lead (Pb) was investigated under laboratory conditions. Both Cd and Pb, even, at very low concentrations, had relatively high toxic effects on S. littoralis larvae. Cd was more toxic to S. littoralis larvae than Pb. In addition, the mean percentage feeding deterrence (FDI%) of Cd and Pb was concentration-dependent. The nutritional indices (consumption index, growth rate, efficiency of converted ingested and digested food, and approximate digestibility) of S. littoralis second and fourth instar larvae were more affected in Cd-treatments compared with those of Pb-treatments. Therefore, the presence of such heavy metals in the environment would exert an adverse impact on S. littoralis larvae and their development. 相似文献
696.
Heba Mohamed Ali Doha El-Sayed Ellakwa Nesma Mohamed Elaraby Amr Mohamed Zaher Khalda Sayed Amr 《Journal of biochemical and molecular toxicology》2023,37(3):e23284
Coronary heart disease (CHD) is the most prevalent cause of cardiovascular mortality in the world. It is well established that microRNAs (miRNAs) and their variants have an essential role in regulating the development of cardiovascular physiology, thus impacting the pathophysiology of heart diseases. This study was designed to determine the possible association of miRNA polymorphisms (miRNA-146a rs2910164C/G and miR-4513 rs2168518G/A) with susceptibility to CHD in Egyptian patients and their correlation with different biochemical parameters. The study comprised 300 participants, including 200 unrelated patients with CHD and 100 healthy controls. Anthropometric and blood biochemical parameters were measured as well genetic analysis for rs2910164C/G and rs2168518G/A polymorphisms were performed for all subjects using TaqMan real-time PCR assay. Our results revealed that the biomedical parameters have a significant correlation between CHD patients and healthy controls with a p < 0.05. Analyses of genotype distribution for (rs2910164 and rs2168518) revealed a significant association with CHD [odd ratio = 4.54, confidence interval (CI 95%) = (2.41–8.53)] and [odd ratio = 0.88, (CI 95%) = (0.83–0.92)], respectively. Furthermore, a statistically significant difference was detected between lipid profile levels and both rs2910164 and rs2168518 polymorphisms. The present study's findings indicated that the selected polymorphisms, miR-146a rs2910164 and miR-4513 rs2168518 could represent a useful biomarker for susceptibility to CHD in the Egyptian population. These genetic characteristics and personal habits and environmental factors may contribute to the development of CHD. 相似文献
697.
Hanan Abo El-Kassem Bosly 《Saudi Journal of Biological Sciences》2021,28(4):2342-2351
A preliminary detective survey for the hymenopteran insect fauna of Jazan Lake dam region, Southwest Saudi Arabia, was carried out for one year from January 2018 to January 2019 using mainly sweep nets and Malaise traps. The survey revealed the presence of three hymenopteran Superfamilies (Apoidea, Vespoidea and Evanioidea) representing 15 species belonging to 10 genera of 6 families (Apidae, Crabronidae, Sphecidae, Vespidae, Mutillidae, and Evaniidae). The largest number of species has belonged to the family Crabronidae is represented by 6 species under 2 genera. While the family Apidae, is represented by 2 species under 2 genera. Family Vespidae is represented by 2 species of one genus. While, the rest of the families Sphecidae, Mutillida, and Evaniidae each is represented by only one species and one genus each. Eleven species are predators, two species are pollinators and two species are parasitics. Note for each family was provided, and species was provided with synonyms and general and taxonomic remarks and their worldwide geographic distribution and information about their economic importance are also included. All species were photographed with dorsal and lateral views. 相似文献
698.
Reda A. I. Abou-Shanab Marwa M. El-Dalatony Mostafa M. EL-Sheekh Min-Kyu Ji El-Sayed Salama Akhil N. Kabra Byong-Hun Jeon 《Biotechnology and Bioprocess Engineering》2014,19(3):510-518
Coupling of advanced wastewater treatment with microalgae cultivation for low-cost lipid production was demonstrated in this study. The microalgal species Micractinium reisseri and Scenedesmus obliquus were isolated from municipal wastewater mixed with agricultural drainage. M. reisseri was selected based on the growth rate and cultivated in municipal wastewater (influent, secondary and tertiary effluents) which varied in nutrient concentration. M. reisseri showed an optimal specific growth rate (μopt) of 1.15, 1.04, and 1.01 1/day for the influent and the secondary and tertiary effluents, respectively. Secondary effluent supported the highest phosphorus removal (94%) and saturated fatty acid content (40%). The highest lipid content (40%), unsaturated fatty acid content, including monounsaturated and polyunsaturated fatty acids (66%), and nitrogen removal (80%) were observed for tertiary effluent. Fatty acids accumulating in the microalgal biomass (M. reisseri) were mainly composed of palmitic acid, oleic acid, linoleic acid, and a-linolenic acid. Cultivation of M. reisseri using municipal wastewater served a dual function of nutrient removal and biofuel feedstock generation. 相似文献
699.
Ahmed A. Ismaiel Ashraf S. Ahmed El-Sayed R. El-Sayed 《World journal of microbiology & biotechnology》2014,30(10):2625-2638
Mycophenolic acid (MPA) is a promising drug owing to its immunosuppressive and biological activities. In this study, two strains of Penicillium roqueforti designated as AG101 and LG109 were selected among several strains isolated from Roquefort cheese samples on the basis of their activity for MPA-producing ability. The appropriate fermentation conditions necessary for MPA biosynthesis by the two respective fungal strains were investigated. These conditions included selection of the cultivation medium, agitation rate, incubation temperature, fermentation time, pH value, inoculum size, and fermentation medium volume. Maximum MPA productivities were maintained when the fermentation process was carried out using a medium composed of (g l?1): Sucrose, 30; peptone, 5.0; KH2PO4, 1.0; MgSO4·7H2O, 0.5 and KCl, 0.5; pH 6.0, inoculated with an inoculum size of 6.0 % (v/v), and incubated at 25 °C for 10 days at 120 rpm. The potentiality of both P. roqueforti strains for further improvement of MPA production was applied by mutagenesis through exposure to irradiation by ultraviolet rays (UV, 254 nm) for different periods of time and gamma rays at various doses (KGy). The dry cell weight of both irradiated fungal strains showed a greater reduction when irradiated either with UV or gamma rays. However, the MPA yield of both strains was increased by 1.27–1.39 fold when irradiated with UV rays and by 2.11–2.33 fold when irradiated with gamma rays, as compared with the respective controls (non-irradiated cultures). These findings indicate the future possibility to reduce the cost of producing fermentation-based drugs. 相似文献
700.
Hemat S. Khalaf Hala E. M. Tolan Mohamed A. A. Radwan Ashraf M. Mohamed Hanem M. Awad Wael A. El-Sayed 《Nucleosides, nucleotides & nucleic acids》2020,39(7):1036-1056
AbstractNew 1,3,4-thiadiazole thioglycosides linked to substituted pyrimidines were synthesized via glycosylation of 1,3,4-thiadiazole thiol compounds. Also, novel 1,2,3-triazole derivatives linked to carbohydrate units were prepared using the standard click chemistry conditions employing the Cu(I)-catalyzed azide-alkyne cycloaddition of substituted-aryl-azides with a selection of alkyne-functionalized sugars. The chemical structures of the new derivatives were verified using various spectroscopic techniques, such as IR, 1H NMR, 13C NMR and elemental analyses. The cytotoxic activities of the prepared compounds were investigated in vitro against human liver cancer (HepG-2) and human breast adenocarcinoma (MCF7) cell lines. In addition, the biological evaluation of the new compounds involved the investigation of their effects on a human normal retinal pigmented epithelial cell line (RPE1) using the MTT assay. 相似文献