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411.
Davood Shayegan Jalal Jalali Sendi Ahad Sahragard Arash Zibaee 《Physiological Entomology》2019,44(2):169-176
The present study investigates the effect of gibberellic acid (GA3), a terpenoid and phytohormone, on the digestive physiology and intermediary metabolism of the cotton bollworm Helicoverpa armigera Hübner (Lepidoptera, Noctuidae). Incorporation of GA3 (800 μg g?1 diet) in an artificial diet results in significant reductions in the rates of diet consumption and the efficiency of conversion of food consumption by by H. armigera larvae. The relative growth rate decreases as the concentration increases. The relative α‐amylase activity in sixth‐instar larvae of H. armigera decreases significantly after ingestion of four concentrations of GA3. Histological studies of the midgut in GA3‐treated larvae (800 μg g?1 diet) show degeneration of the epithelial cells. The alanine and aspartate aminotransferase activity decreases at the highest concentration. However, acid phosphatase, alkaline phosphatase, γ‐glutamyl transferase and lactate dehydrogenase activity increase significantly compared with the control. The results clearly demonstrate the adverse effects of GA3 on H. armigera via interruption of nutritional physiology and metabolism. 相似文献
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Effects of different shear rates (14, 25, and 50 s−1), gum concentrations (3%, 3.5%, and 4%), and temperatures (5–65 °C) on flow properties of Alyssum homolocarpum seed gum solutions were investigated using a rotational viscometer. The experimental data were fitted with three time-dependent
rheological models, namely second-order structural kinetic model, Weltman model, and first-order stress decay model with a
non-zero stress value. The rate constant and extent of viscosity strongly depended on the shear rate, gum concentration, and
temperature. It was found that A. homolocarpum seed gum samples exhibited shear thinning and thixotropic behavior for all concentrations and temperatures. The amount of
structural breakdown decreased with shear rate, but it did not have a general trend with concentration and temperature. The
extent of thixotropy increased with increasing gum concentration and decreased with increasing temperature and shear rate.
In this work, the decay rate constant generally increased with increasing shear rate; however, it did not have any trend with
concentration and temperature. 相似文献
413.
Shima Neamati Masoud Alirezaei Arash Kheradmand 《International journal of peptide research and therapeutics》2011,17(3):239-245
Ghrelin has recently been shown to improve renal function in rat with acute renal failure. In this setting, the protective
effects have been suggested to be due to its antioxidant properties. Thus, the aim of this study was to measure the antioxidant
abilities of this hormone via enzymatic and lipid peroxidation analyses. Wistar rats were divided into two control and two
treatment groups, the treated animals receiving 3 nmol of ghrelin as subcutaneous administrations on each of 10 consecutive
days and physiological saline injected to controls. Catalase (CAT) activity was significantly higher in the treated animals
when compared to controls, while in contrast, lipid peroxidation measured by thiobarbituric acid reactive substances (TBARS),
was significantly reduced in the ghrelin treated animals. Furthermore, superoxide dismutase (SOD) activity and glutathione
(GSH) content were both much higher in treated female rats than in controls and although there was a slight increase in glutathione
peroxidase (GPx) activity in kidneys of ghrelin treated rats, the difference was insignificant. These findings suggest that
ghrelin has beneficial antioxidant properties in the rat kidney by increasing antioxidant enzyme activities. These effects
were more noticeable in treated female rats, possibly due to higher levels of estrogen. 相似文献
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Multilocus genotypic data reveal high genetic diversity and low population genetic structure of Iranian indigenous sheep
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S. M. F. Vahidi M. O. Faruque M. Falahati Anbaran F. Afraz S. M. Mousavi P. Boettcher S. Joost J. L. Han L. Colli K. Periasamy R. Negrini P. Ajmone‐Marsan 《Animal genetics》2016,47(4):463-470
Iranian livestock diversity is still largely unexplored, in spite of the interest in the populations historically reared in this country located near the Fertile Crescent, a major livestock domestication centre. In this investigation, the genetic diversity and differentiation of 10 Iranian indigenous fat‐tailed sheep breeds were investigated using 18 microsatellite markers. Iranian breeds were found to host a high level of diversity. This conclusion is substantiated by the large number of alleles observed across loci (average 13.83, range 7–22) and by the high within‐breed expected heterozygosity (average 0.75, range 0.72–0.76). Iranian sheep have a low level of genetic differentiation, as indicated by the analysis of molecular variance, which allocated a very small proportion (1.67%) of total variation to the between‐population component, and by the small fixation index (FST = 0.02). Both Bayesian clustering and principal coordinates analysis revealed the absence of a detectable genetic structure. Also, no isolation by distance was observed through comparison of genetic and geographical distances. In spite of high within‐breed variation, signatures of inbreeding were detected by the FIS indices, which were positive in all and statistically significant in three breeds. Possible factors explaining the patterns observed, such as considerable gene flow and inbreeding probably due to anthropogenic activities in the light of population management and conservation programmes, are discussed. 相似文献
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Vida Jafari Azad Shahab Kasravi Hojjat Alizadeh Zeinabad Mehri Memar Bashi Aval Ali Akbar Saboury Arash Rahimi 《Journal of biomolecular structure & dynamics》2017,35(12):2565-2577
Herein, the interaction of iron nanoparticle (Fe-NP) with cytochrome c (Cyt c) was investigated, and a range of techniques such as dynamic light scattering (DLS), zeta potential measurements, static and synchronous fluorescence spectroscopy, near and far circular dichroism (CD) spectroscopy, and ultraviolet–visible (UV–vis) spectroscopy were used to analyze the interaction between Cyt c and Fe-NP. DLS and zeta potential measurements showed that the values of hydrodynamic radius and charge distribution of Fe-NP are 83.95 ± 3.7 nm and 4.5 ± .8 mV, respectively. The fluorescence spectroscopy results demonstrated that the binding of Fe-NP with Cyt c is mediated by hydrogen bonds and van der Waals interactions. Also Fe-NP induced conformational changes in Cyt c and reduced the melting temperature value of Cyt c from 79.18 to 71.33°C. CD experiments of interaction between Fe-NP and Cyt c revealed that the secondary structure of Cyt c with the dominant α-helix structures remained unchanged whereas the tertiary structure and heme position of Cyt c are subjected to remarkable changes. Absorption spectroscopy at 695 nm revealed that Fe-NP considerably disrupt the Fe…S(Met80) bond. In addition, the UV–vis experiment showed the peroxidase-like activity of Cyt c upon interaction with Fe-NP. Hence, the data indicate the Fe-NP results in unfolding of Cyt c and subsequent peroxidase-like activity of denatured species. It was concluded that a comprehensive study of the interaction of Fe-NP with biological system is a crucial step for their potential application as intracellular delivery carriers and medicinal agents. 相似文献
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Functional and reversible plasmonic resonances across the visible and near-infrared spectrum have opened new avenues for developing advanced next-generation nanophotonic devices. In this study, by using optothermally controlled phase-change material (PCM) for plasmonic nanostructures, we successfully induced highly tunable charge transfer plasmon (CTP) resonance modes. To this end, we have chosen a two-member dimer assembly consisting of gold cores and Ge2Sb2Te5 (GST) shells in distant, touching, and overlapping regimes. We show that switching between amorphous (dielectric) and crystalline (conductive) phases of GST allows for achieving tunable dipolar and CTP resonances and enables an effective interplay between these modes along the near-infrared spectrum. By analyzing electromagnetically calculated spectral responses for the dimer antenna in tunneling and direct charge transfer regimes, we confirmed that the induced CTPs in touching and overlapping regimes are highly controllable and pronounced in comparison to the quantum tunneling regime. We also use the precise, fast, and controllable switching between dipolar and CTP resonant modes to develop a telecommunication switch based on a simple metallodielectric dimer. The proposed structures can help designing optothermally controlled devices without morphological variations in the geometry of the design, and having strong potential for advanced plasmon modulation and fast data routing. 相似文献