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1.
The pharmacokinetics of promethazine were determined in seven camels (Camelus dromedarius) after an intravenous dose of 0.5 mg kg body weight.-1 The data obtained (median and range) were as follows: the elimination half-life (t1/2 beta) was 5.62 (2.84-6.51) h; the steady state volume of distribution (Vdss) was 8.90 (7.10-12.00) L kg-1, total body clearance (CT) was 24.5 (17.22-33.65) ml kg-1 min-1 and renal clearance (Clr) was 4.81 (1.97-5.48) ml kg-1 min-1.  相似文献   
2.
The pharmacokinetics of etamiphylline were determined after an intramuscular (i.m.) dose of 3.5 mg/kg body weight in six healthy camels. Furthermore, the metabolites and drug detection time were evaluated. The data obtained median and (range) were as follows: the terminal elimination half-life (t(1/2 beta), h) was 3.04 (2.03-3.62); apparent total body clearance (Cl/F, L/h/kg) was 1.27 (0.74-2.99); the apparent volume of distribution at steady state (V(ss)/F, L/kg) was 4.94 (3.57-12.54); and renal clearance (Cl(r), L/h/kg) determined in two camels was 0.005 and 0.004, respectively. The detection time of etamiphylline in urine after an i.m. dose of 3.5 mg/kg body weight ranged between 12 and 13 days. Three etamiphylline metabolites were tentatively identified in camels urine: The first one desethyletamiphylline was the main metabolite and resulted from N-deethylation of etamiphylline had a molecular weight of 251, and was detected in urine for about 13-14 days. Theophylline (molecular weight 180) was the second metabolite and resulted from ring N-dealkylation of etamiphylline. It was present in small amounts and was detected for about 5 h after drug administration in urine. The third metabolite, possibly resulted from demethylation of etamiphylline, had a molecular weight of m/z 265, and was present in small amounts and was detected in urine for about 5 h after drug administration.  相似文献   
3.
A species trial with 14 eucalypt species with randomized complete blocks design was planted on Imperata cylindrica dominated grassland in South Kalimantan, Indonesia in January 1987. The site was prepared mechanically. No fertilizers were used. At the age of three years E. camaldulensis had clearly the highest survival rate (95%) and mean annual increment (5.9 m3ha–1a–1) compared with the other species tried. It was followed by E. urophylla, E. deglupta, E. pellita, E. tereticornis, E. alba, E. torelliana, E. intermedia, E. grandis and E. pilularis. Four other species, E. phaeotricha, E. resinifera, E. cloeziana and E. microcorys died either in the nursery or immediately after planting. All the eucalypts tried had narrow crowns and open canopies. It is suggested that eucalypts are not recommendable for grassland reforestation under minimum plantation tending. Effects of intensive weeding, spacing, fertilizing and performance in second rotation or mixed stands should be tested to elaborate the suitability of eucalypts on grasslands.  相似文献   
4.
BACKGROUND: Busulfan, a cytotoxic drug, which is currently used as a chemotherapeutic agent, has many side effects on different body organs. In this research, the effects of busulfan on sperm parameters and microstructure of mouse testis were investigated. METHODS: Busulfan was injected intrapretoneally at 10, 20, 30, 40 and 50 mg/kg and testes were removed after 4, 6 and 8 weeks, weighed and processed for light microscopic examination. Transverse and cross section diameters of testes, seminiferous tubules diameters, percentage of different types of tubules, epithelium thickness, spermatogenic cell numbers and capsule thickness as well as the sperm parameters in epididymis were measured. RESULTS: There was a significant decline in sperm numbers and marked changes in testes structures. Almost 8 weeks after the injection of drug, some of the changes are reversed. Accordingly, the changes in percent of normal tubules without sperm, abnormal tubules and capsule thickness were increased until 6 weeks of drug administration, the changes declined thereafter. CONCLUSION: In general, busulfan caused a decrease in all analyzed parameters (except capsule thickness, normal tubules without sperm and abnormal tubules), probably due to the arrest of spermatogenesis. Our results also revealed that some of the changes are reversible and dose dependent.  相似文献   
5.
Hadi Ahmadi  Farhad Nazarian 《Euphytica》2007,158(1-2):103-108
The homoeologous groups of chromosomes carrying the genes for some morphological traits in wild wheat Triticum turgidum L. ssp. dicoccoides (T. dicoccoides) were determined, but not the actual chromosomes carrying them. The objectives of this study were to investigate the modes of inheritance, and determine the chromosomes carrying some morphological traits in wild emmer (2n = 28; AABB), the progenitor of most cultivated wheats. To investigate the inheritance of morphological traits, crosses were made between T. turgidum L. ssp. durum (T. durum cultivar Chartokhmi (IR10) and T. dicoccoides accessions TA1150 and TA1131. F2 seeds from each cross were grown in the field and six qualitative characters were investigated. Purple coleoptile, purple auricle, purple culm, hairy auricle, hairy rachilla, and fragility of spike were controlled by single dominant genes. To determine the chromosomal locations, accession TA1131 was crossed with the complete set of LDN D-genome disomic substitution lines. Assessments of F2 populations showed that chromosomes 7A, 6A, 7B, 5B, 5A and 3B carried genes for purple coleoptile, purple auricle, purple culm, hairy auricle, hairy rachilla and brittle rachis, respectively.  相似文献   
6.
Iran supports five different vegetation zones. One of those is the Irano-Touranian zone that is located in the northeast of Iran. This vegetation zone includes arid and semi-arid lands, and its area is about 3.5 million hm2. It supports growth of pistachio (Pistacia vera), a deciduous-broadleaved species, which is one of the ecologically and economically most important native species. In this study, we analyzed three images acquired by ALOS satellite, including 10m resolution multispectral band (AVNIR-2), 2.5 m resolution “Backward” PRISM image, and 2.5 m resolution “Nadir” PRISM image, based on a provided rational polynomial coefficient (RPC). Using the “Backward” and “Nadir” images, a 2.5 m resolution digital elevation model (DEM) was produced. Four methods with AVNIR-2 and PRISM data were used to produce pan-sharpening images and conduct an object-based feature extraction process. Normalized Difference Vegetation Index (NDVI) was used to determine the maximum distribution of pistachio in related elevation. The accuracy of the DEM was tested on 28 ground control points in the pair image as tie points, with the value of parallax error of 0.9027 m. The created elevation map indicated that pistachio trees grow up at 650m above sea level (a.s.l.). The result from NDVI in the related elevation showed the maximum density of pistachio at 800m a.s.l. In addition, the result of feature extraction in the forest showed the area of each target element calculated. The results of this research will improve decision-making and lead to sustainable management in general.  相似文献   
7.
Diatoms are unicellular algae with plastids acquired by secondary endosymbiosis. They are responsible for approximately 20% of global carbon fixation. We report the 34 million-base pair draft nuclear genome of the marine diatom Thalassiosira pseudonana and its 129 thousand-base pair plastid and 44 thousand-base pair mitochondrial genomes. Sequence and optical restriction mapping revealed 24 diploid nuclear chromosomes. We identified novel genes for silicic acid transport and formation of silica-based cell walls, high-affinity iron uptake, biosynthetic enzymes for several types of polyunsaturated fatty acids, use of a range of nitrogenous compounds, and a complete urea cycle, all attributes that allow diatoms to prosper in aquatic environments.  相似文献   
8.
The aim of this study was the evaluation of the methods to increase the yield of potato and the accumulation of iron (Fe) and zinc (Zn) in response to iron and zinc fertilizers. In these studies, ‘Marfona’ potato (Solanum tuberosum) cultivar was used in a statistical factorial design experiment with three factors: methods of fertilizer application (2 levels of spray and one level by irrigation), kind of fertilizers (iron and zinc) and levels of fertilizer, (0, 1, 2, and 3 mg L?1). Results showed that iron and zinc fertilizers increased the tubers weight and the tubers number weight?1 ratio (P < 0.01). Also, results showed that the effects of Fe and Zn fertilizers application in irrigation water was more significant (P < 0.01) than by spray application. In addition, application of Fe and Zn fertilizers resulted in higher concentrations of these ions in the harvested tubers improving their nutritional values.  相似文献   
9.
This study investigated effect of increasing level of dietary sodium using sodium bicarbonate or sodium chloride on growth performance, mortality, characteristics of carcass, organs and tibia, calcium and phosphorus of serum in broilers reared in a high‐altitude area (1,700 m above sea level). A total of 588 Ross 308 male broiler chicks were used in seven treatments, six replicates per treatment of 14 birds per each from 1 to 38 d of age. Seven dietary treatments consisted of a basal diet (with 0.16% sodium and 0.23% chloride), top‐dressed for six diets to give three supplementary levels of sodium (0.07%, 0.14% and 0.21%) from sodium bicarbonate (respectively by 0.26%, 0.52% and 0.78%) or sodium chloride (respectively by 0.18%, 0.36% and 0.54%), resulting in seven diets with total sodium and chloride levels of 0.16% and 0.23%, 0.23% and 0.23%, 0.30% and 0.23%, 0.37% and 0.23%, 0.23% and 0.33%, 0.30% and 0.44%, 0.37% and 0.55% respectively. Increasing sodium level improved feed conversion ratio (FCR) linearly and quadratically. However, when FCR was calculated without adjusting for feed intake of mortalities, the enhanced sodium level did not improve this parameter. Increasing sodium level via sodium chloride enhanced ascites mortality, total mortality, relative weight of heart and right ventricle linearly. Increasing sodium level reduced serum calcium and enhanced serum phosphorus linearly; however, there was a linear tendency to increase tibia ash when sodium level was enhanced by sodium bicarbonate (p = 0.08) or sodium chloride (p = 0.07). Increasing sodium level via sodium bicarbonate tended (p = 0.08) to reduce tibia strength linearly. In conclusion, a diet with 0.16% sodium and 0.23% chloride is enough for broiler chicken reared in a high‐altitude area, and increasing dietary sodium level via sodium chloride has detrimental effect on survivability of broiler in such condition.  相似文献   
10.
Spermatozoa concentration, ionic composition, osmolality, glucose and total protein contents of seminal plasma and sperm motility were determined in Barbus sharpeyi (Cyprinidae, Teleosotei). Spermatozoa concentration ranged from 9.77 to 20.20 × 109 spermatozoa mL?1. Osmolality (mOsmol kg?1) and ionic contents (mM L?1) of the seminal plasma were 274.5±9.0, 70.0±3.4 Na+, 28.8±0.9 K+, 101.7±3.1 Cl?, 0.9±0.1 Mg2+ and 2.1±0.1 Ca2+ respectively. Total protein and glucose were 5.3±0.2 g L?1 and 76.7±4.3 mM L?1 respectively. Sperm motility was initiated in a hypo‐osmotic condition, composed of either an ionic (KCl or NaCl) or a non‐ionic (sucrose) activation medium. Duration of sperm motility was very short: <2 min after activation in distilled water. Percentage of motile spermatozoa was significantly higher in an activation medium containing NaCl compared with that of distilled water. An activating medium containing NaCl or KCl higher than 150 mM or sucrose higher than 275 mM totally inhibited the activation of sperm motility. Immediately after sperm activation, wave(s) propagated along the flagellum, but waves were restricted to the proximal part of the flagellum (close to the head) at 1 min post activation. Studied characteristics in the present study were compared with those of other cyprinids for understanding inter‐species differences.  相似文献   
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