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341.
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
342.
Background
Cerebrovascular disease is the second commonest cause of death, and over a third of stroke deaths occur in developing countries. To fulfil the current gap on data, this systematic review is focused on the frequency of stroke, risk factors, stroke types and mortality in Iran. 相似文献343.
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345.
Esmail Jafari Abdus Saleem Bahu S. Shaikh Laurence M. Demers 《Prostaglandins & other lipid mediators》1976,12(5):829-835
When platelet rich plasma is exposed to N-ethylmaleimide, a ten fold increase in measurable prostaglandin E synthesis occurs. This effect is almost completely abolished within 2 hours of ingestion of 600 mg of aspirin by human volunteers. Recovery of this platelet function is slow for the first two days, returning sharply to normal over the next six days and plateauing approximately 8 days following initial removal from aspirin. It is suggested from these studies that platelet prostaglandin E production following NEM may be a useful test of platelet function. 相似文献
346.
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