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81.
82.
The anabolic action of intermittent parathyroid hormone on cortical bone depends partly on its ability to induce nitric oxide‐mediated vasorelaxation in BALB/c mice 下载免费PDF全文
S Gohin A Carriero C Chenu AA Pitsillides TR Arnett M Marenzana 《Cell biochemistry and function》2016,34(2):52-62
There is strong evidence that vasodilatory nitric oxide (NO) donors have anabolic effects on bone in humans. Parathyroid hormone (PTH), the only osteoanabolic drug currently approved, is also a vasodilator. We investigated whether the NO synthase inhibitor L‐NAME might alter the effect of PTH on bone by blocking its vasodilatory effect. BALB/c mice received 28 daily injections of PTH[1–34] (80 µg/kg/day) or L‐NAME (30 mg/kg/day), alone or in combination. Hindlimb blood perfusion was measured by laser Doppler imaging. Bone architecture, turnover and mechanical properties in the femur were analysed respectively by micro‐CT, histomorphometry and three‐point bending. PTH increased hindlimb blood flow by >30% within 10 min of injection (P < 0.001). Co‐treatment with L‐NAME blocked the action of PTH on blood flow, whereas L‐NAME alone had no effect. PTH treatment increased femoral cortical bone volume and formation rate by 20% and 110%, respectively (P < 0.001). PTH had no effect on trabecular bone volume in the femoral metaphysis although trabecular thickness and number were increased and decreased by 25%, respectively. Co‐treatment with L‐NAME restricted the PTH‐stimulated increase in cortical bone formation but had no clear‐cut effects in trabecular bone. Co‐treatment with L‐NAME did not affect the mechanical strength in femurs induced by iPTH. These results suggest that NO‐mediated vasorelaxation plays partly a role in the anabolic action of PTH on cortical bone. © 2016 The Authors. Cell Biochemistry and Function published by John Wiley & Sons, Ltd. 相似文献
83.
土壤中棉花黄萎病菌SYBR Green Ⅰ荧光RT-PCR定量检测技术研究 总被引:3,自引:0,他引:3
为实现田间土壤棉花黄萎病菌的早期检测,建立了土壤中棉花黄萎病菌的SYBR Green I荧光定量PCR检测方法。以含342bp PCR扩增产物的阳性质粒为参考,构建了标准曲线,并对该曲线的特异性、敏感性、可重复性进行了评价。结果表明,该方法具有快速、特异性强、敏感度高等特点。检测范围在3.8×103-3.8×108copies/μL之间有良好的线性关系,相关系数R2为0.996,扩增效率为101.5%,灵敏度比常规PCR方法高102倍。 相似文献
84.
Ahmed Mostafa Soliman Neveen Samy Gadallah Hathal Mohammed Al Dhafer 《Zoology in the Middle East.》2017,63(1):58-62
In the present study, the genus Gynecaptera Skorikov, 1935 is recorded from the Arabian Peninsula for the first time, with a nocturnal new species, G. arabica Soliman &; Gadallah, which has been collected from the Riyadh region in Saudi Arabia and which is described and illustrated.http://www.zoobank.org/urn:lsid:zoobank.org:pub:F7ACB779-3750-4DC6-B29B-B7F290E7C7B4 相似文献
85.
Moustafa A. Abbassy Mona A. Abdel-Rasoul Belal S. M. Soliman 《Archives Of Phytopathology And Plant Protection》2017,50(17-18):909-926
Current study investigated the nematicidal activity of leaf extracts of Conyza dioscoridis, Melia azedarach, and Moringa oleifera that were prepared as silver nanoparticles (Ag-NP). The characterisation and size confirmation of the Ag-NP were done by UV–vis spectrophotometry and the scanning electron microscopy (SEM). The phytochemical contents of crude extracts and the nano formulations were analysed using gas chromatography-mass spectroscopy (GC-MS). Results revealed that silver nanoparticles of C. dioscoridis extractives had great nematicidal activity against the 2nd stage juvenile (J2) and eggs of Meloidogyne incognita. Also, the Ag-NP showed similar nematicidal effect to the reference nematicide; rugby. The GC-MS analysis revealed the increase of certain metabolites due to the formulation of the Ag-NPs. Aromadendrene, 1-hydroxy-1,7-dimethyl-4-isopropyl-2,7-cyclodecdiene, 6-epi-shyobunol, 4-hexylacetophenone, β-isocomene, caryophyllene, β- and α-selinene, α-cadinol, berkheyaradulen, and bis-(2-ethylhexyl)phthalate were increased more than 2.5-folds in the Ag-NP compared the extract. Therefore, the green synthesis of metal nanoparticles might be a safe, effective and affordable nematicide alternatives. 相似文献
86.
Many models in Systems Biology are described as a system of Ordinary Differential Equations, which allows for transient, steady-state or bifurcation analysis when kinetic information is available. Complementary structure-related qualitative analysis techniques have become increasingly popular in recent years, like qualitative model checking or pathway analysis (elementary modes, invariants, flux balance analysis, graph-based analyses, chemical organization theory, etc.). They do not rely on kinetic information but require a well-defined structure as stochastic analysis techniques equally do. In this article, we look into the structure inference problem for a model described by a system of Ordinary Differential Equations and provide conditions for the uniqueness of its solution. We describe a method to extract a structured reaction network model, represented as a bipartite multigraph, for example, a continuous Petri net (CPN), from a system of Ordinary Differential Equations (ODEs). A CPN uniquely defines an ODE, and each ODE can be transformed into a CPN. However, it is not obvious under which conditions the transformation of an ODE into a CPN is unique, that is, when a given ODE defines exactly one CPN. We provide biochemically relevant sufficient conditions under which the derived structure is unique and counterexamples showing the necessity of each condition. Our method is implemented and available; we illustrate it on some signal transduction models from the BioModels database. A prototype implementation of the method is made available to modellers at http://contraintes.inria.fr/~soliman/ode2pn.html, and the data mentioned in the "Results" section at http://contraintes.inria.fr/~soliman/ode2pn_data/. Our results yield a new recommendation for the import/export feature of tools supporting the SBML exchange format. 相似文献
87.
Monier Abd El‐Ghani Abdel M. El‐Fiky Ashraf Soliman Adel Khattab 《African Journal of Ecology》2011,49(1):103-118
In generalized four sectors, 350 stands (water channels) in 50 selected and geo‐referenced sites with eighteen environmental factors were surveyed. The total number of recorded species varied from a sector to another: 21 in the northern, nineteen in the middle, seventeen in the western and sixteen in the eastern. New populations of Cyperus papyrus were explored. Vallisneria spiralis, Elodea canadensis and Najas armata were among seven extinct species that were not recorded few decades ago. The floristic composition alteration may be because of the addition of organic matter of plant and animal origin and the discharge of industrial and sewage effluents. Classification and ordination analyses (DCA) resulted in the segregation of seventeen vegetation groups (communities), three of them were repeatedly recorded; namely Phragmites australis‐Eichhornia crassipes, Phragmites australis‐Myriophyllum spicatum and Potamogeton pectinatus‐Myriophyllum spicatum. Phragmites australis‐Cyperus papyrus group was a new community spreading in the eastern sector of the Delta. Electric conductivity, Fe, Hg and chemical oxygen demand (COD) showed high significant variation (P < 0.001) among the vegetation groups. Other significant variables were Cl, Ca, NO3, pH and SO4 (P < 0.047). Redundancy analysis (RDA) was chosen as the appropriate ordination method to perform direct gradient analysis. Trace elements Cu, Fe, Hg and Pb participated in the floristic and chemical composition of each sector. 相似文献
88.
Gayle M. Lorenzi Barbara H. Braffett Valerie L. Arends Ronald P. Danis Lisa Diminick Kandace A. Klumpp Anthony D. Morrison Elsayed Z. Soliman Michael W. Steffes Patricia A. Cleary the DCCT/EDIC Research Group 《PloS one》2015,10(11)
Implementation of multicenter and/or longitudinal studies requires an effective quality assurance program to identify trends, data inconsistencies and process variability of results over time. The Diabetes Control and Complications Trial (DCCT) and the follow-up Epidemiology of Diabetes Interventions and Complications (EDIC) study represent over 30 years of data collection among a cohort of participants across 27 clinical centers. The quality assurance plan is overseen by the Data Coordinating Center and is implemented across the clinical centers and central reading units. Each central unit incorporates specific DCCT/EDIC quality monitoring activities into their routine quality assurance plan. The results are reviewed by a data quality assurance committee whose function is to identify variances in quality that may impact study results from the central units as well as within and across clinical centers, and to recommend implementation of corrective procedures when necessary. Over the 30-year period, changes to the methods, equipment, or clinical procedures have been required to keep procedures current and ensure continued collection of scientifically valid and clinically relevant results. Pilot testing to compare historic processes with contemporary alternatives is performed and comparability is validated prior to incorporation of new procedures into the study. Details of the quality assurance plan across and within the clinical and central reading units are described, and quality outcomes for core measures analyzed by the central reading units (e.g. biochemical samples, fundus photographs, ECGs) are presented. 相似文献
89.
Photosynthetic enhancement studies performed at 619 nm (excitation of Systems I and II) and at 446 nm (mainly excitation of System I) revealed an 18% photosynthetic enhancement simultaneously with a 31% reduction in glycolate excretion. This observation supports the hypothesis that some glycolate may be consumed in an oxidation process associated with System I when System II is poorly excited and the supply of electrons from the water splitting process of photosynthesis is low. 相似文献
90.
Amin KM Ismail MM Noaman E Soliman DH Ammar YA 《Bioorganic & medicinal chemistry》2006,14(20):6917-6923
Hypoxic cells which are common feature of solid tumors are resistant to both anticancer drugs and radiation therapy. Thus, the identification of drugs with the selective toxicity toward hypoxic cells is an important target in anticancer chemotherapy. Tirapazamine has been shown to be an efficient and selective cytotoxin after bioreductive activation in hypoxic cells which is thought to be due to the presence of the 1,4-di-N-oxide. A new series of quinoxaline 1,4-di-N-oxides and fused quinoxaline di-N-oxides were synthesized and evaluated for hypoxic-cytotoxic activity on EAC cell line. Compound 10a was the most potent cytotoxin IC(50) 0.9 microg/mL, potency 75 microg/mL, and was approximately 15 times more selective cytotoxin (HCR>111) than 3-aminoquinoxaline-2-carbonitrile which has been used as a standard (HCR>7.5). Compounds 4 and 3a,b were more selective than the standard. In addition, antitumor activity against Hepg2 (liver) and U251 (brain) human cell lines was evaluated, compounds 9c and 8a were the most active against Hepg2 with IC(50) values 1.9 and 2.9 microg/mL, respectively, however, all the tested compounds were nontoxic against U251 cell line. 相似文献