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101.
The pharmacokinetics of orphenadrine (ORPH) following a single intravenous (i.v.) dose was investigated in six camels (Camelus dormedarius). Orphenadrine was extracted from the plasma using a simple sensitive liquid–liquid extraction method and determined by gas chromatography/mass spectrometry (GC/MS). Following i.v. administration plasma concentrations of ORPH decline bi-exponentially with distribution half-life (t1/2α) of 0.50 ± 0.07 h, elimination half-life (t1/2β) of 3.57 ± 0.55 h, area under the time concentration curve (AUC) of 1.03 ± 0.10 g/h l−1. The volume of distribution at steady state (Vdss) 1.92 ± 0.22 l kg−1, volume of the central compartment of the two compartment pharmacokinetic model (Vc) 0.87 ± 0.09 l kg−1, and total body clearance (ClT) of 0.60 ± 0.09 l/h kg−1. Three orphenadrine metabolites were identified in urine samples of camels. The first metabolite N-desmethyl-orphenadrine resulted from N-dealkylation of ORPH with molecular ion m/z 255. The second N,N-didesmethyl-orphenadrine, resulted from N-didesmethylation with molecular ion m/z 241. The third metabolite, hydroxyl-orphenadrine, resulted from the hydroxylation of ORPH with molecular ion m/z 285. ORPH and its metabolites in camel were extensively eliminated in conjugated form. ORPH remains detectable in camel urine for three days after i.v. administration of a single dose of 350 mg orphenadrine aspartate. 相似文献
102.
Pharmacokinetics, metabolism and urinary detection time of flunixin after intravenous administration in camels 总被引:4,自引:0,他引:4
I.A. Wasfi N.S. Boni A.A. Abdel Hadi M. ElGhazali O. Zorob N.A. Alkatheeri & I.M. Barezaiq 《Journal of veterinary pharmacology and therapeutics》1998,21(3):203-208
The pharmacokinetics of flunixin were determined after an intravenous dose of 1.1 mg/kg body weight in six camels and 2.2 mg/kg body weight in four camels. The data obtained (mean ± SEM) for the low and high dose, respectively, were as follows:
The elimination half-lives ( t½β ) were 3.76 ± 0.24 and 4.08 ± 0.49 h, the steady state volumes of distribution ( V dss ) were 320.61 ± 38.53 and 348.84 ± 35.36 mL/kg body weight, total body clearances ( Cl T ) were 88.96 ± 6.63 and 84.86 ± 4.95 mL/h/kg body weight and renal clearances ( Cl r ) were 0.52 ± 0.09 and 0.62 ± 0.18 mL/h/kg body weight. A hydroxylated metabolite of flunixin was identified by gas chromatography/mass spectrometry (GC/MS) under electron and chemical ionization and its major fragmentation pattern was verified by tandem mass spectrometry (GC/MS/MS) using neutral loss, daughter and parent scan modes. The detection times for flunixin and its hydroxylated metabolite in urine after an intravenous (i.v.) dose of 2.2 mg/kg body weight were 96 and 48 h, respectively. 相似文献
The elimination half-lives ( t
103.
1. Changes in respiratory rate (f), rectal temperature (Tr ) and blood acid‐base values were measured in laying hens exposed to ambient temperatures (Ta) of 32, 35, 38 or 41 °G.
2. At Ta 32 °G there was no panting. At Ta 35 °G panting occurred without any increase in Tr but there was a slight alkalosis (pH 7.55).
3. At Ta 38 °G Tr increased and panting was accompanied by moderate alkalosis (pH 7.58).
4. At Ta 41 °G Tr increased considerably and severe alkalosis developed (pH 7.65).
5. From the relation between Tr , f and pH it is concluded that some degree of alkalosis is a normal response to panting in the laying hen. 相似文献
104.
105.
Nasrin Nasiri Mohammad R.Marvie Mohadjer Vahid Etemad Kiomars Sefidi Leila Mohammadi Maryam Gharehaghaji 《林业研究》2018,(4)
For developing nature-based silvicultural practices in a beech forest to promote, abundance, height,vitality, and preferred growth form, regenerated trees growing in gaps were compared with those under closed canopies.A systematic 50×50 m grid was plotted in a beech stand in the Kheyrud Experimental Forest for selecting trees to measure variables in gaps and under closed canopies.Abundance and mean height of regenerated beech trees were significantly higher in closed canopies than in canopy gaps.Beech seedlings with excurrent growth were significantly taller within regeneration patches under closed canopy.Moreover, regenerated trees with high vitality were more abundant in closed canopy areas than in gaps.Thus, beech regeneration should improve under closed canopies; hence, gaps in a near natural forest should be created only after adequate regeneration and appropriate growth under the parent tree in a closed canopy area is ensured.The results of this research have profound implications for the sustainable management of the forest and for ensuring sustainable beech regeneration.The presence of a closed canopy cover likely will reduce potential stresses on oriental beech regeneration. 相似文献
106.
Potato is a staple food crop and the most important agricultural commodity, which critically affects food security and economic stability in Hamadan Province, Iran. Ex-ante sustainability appraisal of new cropping systems and their comparisons with conventional systems can increase the efficiencies of innovations and changes within the production process. This study aimed to explore the sustainability levels of potato cropping systems in Hamadan Province, Iran. To this end, DEXi methodology was developed for the sustainability assessment of the cropping systems. For assessing the three dimensions of environmental, economic, and social sustainability in the four systems of traditional potato system (TPS), Quasi-industrial potato system (QIPS), industrial potato system (IPS), and government-promoted potato system (GPPS), five groups of features were utilized: (1) irrigation method; (2) seed placement; (3) farm machinery use; (4) agrochemical use; and (5) rotation. The impact assessments of the cropping systems were based on two, three, and two groups of ecological, social, and economic indicators, respectively. Employment, supply chain, protection, operational difficulty, productivity, profitability, input use, and biodiversity resulted in 21 basic indicators and 13 aggregated indicators, by which the cropping systems were described. The results revealed that GPPS with distinctive economic and social profiles could have a better overall sustainability despite the fact that some indicators like biodiversity could be negatively affected. Finally, three strategies were recommended for the sustainability of GPPS as follows: biodiversity enhancement, input substitution, and integrated water management. 相似文献
107.
Mozhgan Hosseinnezhad Kamaladin Gharanjig Samaneh Belbasi Seyed Hadi Seied Saadati Mohammad Reza Saeb 《Fibers and Polymers》2018,19(9):1908-1912
Dyeing is a state-of-the-art realm of textile engineering, however, the emphasis on petroleum-based products is now shifting towards green fibers, particularly, green manufacturing processes. In the present work, a natural mordant, sumac, was extracted and used alone and in combination with alum (a mineral mordant) in silk fibers dyeing with madder and Reseda green dye to make the green production of Iranian carpet possible. The FT-IR ATR spectra of the washed, mordanted, and mordanted dyed silk fibers revealed bonding between silk fibers and green materials. The color of the silk fibers dyed with madder and Reseda extraction was quantified in terms of CIELab (L*, a*, and b*) and K/S values. The effects of different treatments on fastness properties including light, wash, and rubbing fastness were assessed by ISO standard test method. 相似文献
108.
Tariq M Ali G Hadi F Ahmad S Ali N Shah AA 《Pakistan journal of biological sciences: PJBS》2008,11(2):255-259
The objective of the present study was to develop an effective protocol for optimum callus induction and complete plant regeneration for four varieties of rice (Oryza sativa L.) i.e., Super Basmati, Basmati-370, Basmati-371 and Fakhre Malakand. Calli were induced from mature seed scutelum. The Murashige and Skoog (MS) and Chu's N6 media containing hormone 2, 4-D (2, 4-Dichlorophenoxy acetic acid) in different concentrations were used for callus induction. Fakhre Malakand produced maximum calli on N6 media containing 3 mg L(-1) 2,4-D. while other three varieties showed maximum callus induction on N6 media containing 2.5 mg L(-1) 2,4-D. N6 media was found better than MS media for callus induction. For complete plant regeneration the calli of two varieties i.e., Basmati-370 and Basmati-371 were plated on N6 media containing different concentrations of NAA (1-Naphthalene acetic acid) and BAP (6-benzyl aminopurine). The maximum regeneration frequency (%) was observed on N6 media containing NAA 1 mg L(-1) and BAP 2.5 mg L(-1). It took 27-30 days for the callus to regenerate into a complete plant. Basmati-370 produced 4-7 plantlets per callus whereas Basmati-371 produced 4-8 plantlets per callus with regeneration frequencies of 61 and 69%, respectively. 相似文献
109.
Mohammad Reza Imanpoor Sayed Hadi Alavi Jacky Cosson 《Fish physiology and biochemistry》2009,35(4):701-707
We have determined a number of biological characteristics of the Persian sturgeon egg (including diameter, surface-to-volume
ratio, yolk sphere and perivitelline space) and of female brood stocks (including age, length, weight, condition and absolute
fecundity) in 420 specimens of the migratory population of Acipenser persicus in Gorgan bay of Iran from 2001 to 2004. In the hydrated egg, the average egg diameter, yolk diameter, surface-to-volume
ratio and yolk sphere-to-perivitelline space ratio values were: 3.64 ± 0.17 mm, 3.26 ± 0.25 mm, 1.65 ± 0.08 and 0.75 ± 0.01,
respectively. In this chondrostean species, the egg surface and volume were found to increase with increasing egg diameter,
but the egg surface-to-volume ratio decreased. In Persian sturgeon, the surface-to-volume ratio and yolk sphere-to-perivitelline
space ratio is very high; therefore, the metabolic rate is low and female spawning occurs in low-temperature waters. The statistical
Pearson correlation between egg diameter relative to a number of brood stock characteristics, including fork length (r = 0.059), weight (r = 0.140), age (r = 0.081) and absolute fecundity (r = 0.095), were not significantly different (P > 0.05). An extensive comparison of these results with data published on other fish species is presented and discussed. 相似文献
110.
Kayane Pereira Besen Erick William Hessa Melim Larissa da Cunha Emanuel Danieli Favaretto Marcelo Moreira Thiago El Hadi Perez Fabregat 《Aquaculture Research》2019,50(8):2200-2206
This study aimed to evaluate the effect of lutein supplementation on growth, survival and skin pigmentation for goldfish juveniles. Four diets enriched with different carotenoid sources (lutein, astaxanthin, canthaxanthin and a combination of lutein and canthaxanthin) were compared to a control diet without carotenoid supplementation. The carotenoid inclusion level was standardized at 50 mg kg‐1 in all treatments. 240 goldfish juveniles (1.07?0.57 g) were cultivated in 30 aquariums (30L) during 84 days. The experimental design was completely randomized with five treatments and six replicates. The dietary inclusion of carotenoid pigments did not affect the growth and feeding efficiency of goldfish juveniles. Supplementation with lutein presented higher survival values when compared to the other treatments. Astaxanthin and canthaxanthin supplementation increased the concentration of carotenoids on the skin of goldfish juveniles in relation to the control treatment. For the fish fed with the diet containing lutein, the skin pigmentation was as efficient as astaxanthin and canthaxanthin, but did not differ from the control and combined treatment (canthaxanthin + lutein). The lutein supplementation (50 mg kg‐1) improved survival and promoted efficient carotenoid pigmentation on the skin of goldfish juveniles. 相似文献