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1.
Furosemide is a potent loop diuretic used for the prevention of exercise-induced pulmonary hemorrhage in horses. This drug may interfere with the detection of other substances by reducing urinary concentrations, so its use is strictly regulated. The regulation of furosemide in many racing jurisdictions is based on paired limits of urinary SG (<1.010) and serum furosemide concentrations (>100 ng/ml). To validate this regulatory mechanism, a liquid chromatography/mass spectrometry/mass spectrometry method employing a solid-phase extraction procedure and furosemide-d5 as an internal standard was developed. The method was used to determine the pharmacokinetic parameters of furosemide in equine serum samples and its effects on urinary SG after IV administration (250 mg) to 10 horses. Pharmacokinetic analysis showed that serum concentrations of furosemide were well described by a two-compartmental open model. Based on results in this study, it is very unlikely for horses to have serum furosemide concentrations greater than 100 ng/ml or urine SG less than 1.010 at 4 hours after administration (250 mg IV). However, it should be remembered that urine SG is a highly variable measurement in horses, and even without furosemide administration, some horses might naturally have urine SG values less than 1.010.  相似文献   
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Temperature (high and low) is one of the most limiting environmental factors for growth and production of fruits in different parts of the world. For temperate-zone fruit species, a certain total heat requirements are needed in order to obtain ripe fruits. The aim of this study was to determine heat requirements of three commercial pomegranate cultivars (‘Suruc’, ‘Katirbasi’ and ‘Hicaznar’) grown in Southern Anatolia region. The cultivars showed a narrower range of heat requirements for flowering (growing degree hours, GDH), i.e. ‘Suruc’ (25,000), ‘Katirbasi’ (25,270), ‘Hicaznar’ (28,000) and a wide range of heat requirements for fruit ripening, i.e. ‘Suruc’ (73,670), ‘Katirbasi’ (74,105) and ‘Hicaznar’ (88,052) GDH. Under the Sanliurfa province conditions, two years average of effective heat summation requirement from bud swelling to 50 % flowering stage for ‘Suruc’, ‘Katirbasi’ and ‘Hicaznar’ cultivars are calculated as 643, 655 and 718 growing degree days (GDD) and from bud swelling to harvest are 2734, 2802 and 3289 GDD. It can be concluded that the effective heat summation of Sanliurfa province is enough for commercial growing for all pomegranate cultivars.  相似文献   
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The acaricidal effects of the volatile essential oil Origanum minutiflorum O. Schwarz & P.H. Davis (Lamiaceae) against adult Rhipicephalus turanicus was evaluated at a variety of concentrations and exposure times. Generally tick mortality increased with concentration and exposure. Ticks exposed to vapors from cotton wicks containing at least 10 μl/L resulted in complete (100%) mortality at 120 min. The major constituent of essential oil obtained from the plant material of O. minutiflorum was carvacrol.  相似文献   
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Nineteen wild emmer wheat [Triticum turgidum ssp. dicoccoides (Körn.) Thell.] genotypes were evaluated for the grain concentrations of phosphorous (P), potassium (K), sulfur (S), magnesium (Mg), calcium (Ca), zinc (Zn), manganese (Mn), iron (Fe) and cooper (Cu) under five different environments in Turkey and Israel. Each mineral nutrient has been investigated for the (1) genotype by environment (G × E) interactions, (2) genotype stability, (3) correlation among minerals and (4) mineral stability. Among the macronutrients analyzed, grain concentrations of Ca (range 338–2,034 mg kg?1) and S (range 0.18–0.43%) showed the largest variation. In the case of micronutrients, the largest variation was observed in the grain Mn concentration (range 13–87 mg kg?1). Grain concentrations of Fe and Zn also showed important variation (range 27–86 and 39–115 mg kg?1, respectively). Accessions with higher nutrient concentrations (especially Zn and Fe) had also greater grain weight, suggesting that higher grain Zn and Fe concentrations are not necessarily related to small grain size or weight. Analysis of variance showed that environment was the most important source of variation for K, S, Ca, Fe, Mn and Zn, explaining between 44 and 78% of the total variation and G × E explained between 20 and 40% of the total variation in all the minerals, except for S and Zn where its effect accounted for less than 16%. Genotype was the most important source of variation for Cu (explaining 38% of the total variation). However, genotype effect was also important for Mg, Mn, Zn and S. Sulfur and Zn showed the largest heritability values (77 and 72%, respectively). Iron exhibited low heritability and high ratio value between the G × E and genotype variance components \( \left( {\sigma_{\text{GE}}^{2} /\sigma_{G}^{2} } \right) \), suggesting that specific adaptation for this mineral could be positively exploited. The wild emmer germplasm tested in the current study revealed some outstanding accessions (such as MM 5/4 and 24-39) in terms of grain Zn and Fe concentrations and environmental stability that can be used as potential donors to enhance grain micronutrient concentrations in wheats.  相似文献   
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Murata vortex spinning system is based on the air jet spinning system. The vast majority of previous works deal with the properties of vortex spun (VS) yarn and the spinning system. In this study, we investigated knitted fabrics from VS yarn in comparison with fabrics from ring (RS), compact (CS) and open-end rotor (OES) spun yarns made from viscose. The effect of yarn spinning system on dimensional and physical properties of knitted fabrics was explained with specific attention to fabrics from VS yarn. Shrinkage of fabrics from VS yarn has the lowest at widthwise direction, while having the highest at lengthwise direction. It is shown that the order of fabric spirality and twist liveliness for yarns from different spinning systems are quite similar. However, relation between loop shape factor and angle of spirality is inconsistent. Angle of spirality of fabrics from VS yarn is higher than fabrics from OES yarn, but lower than that of others. The bursting strength of fabrics from VS yarn is lower than that of those from RS and CS yarns and higher than that of those from OES yarn. From this study, it is also evident that fabrics from VS yarn have the lowest pilling tendency and highest resistance to abrasion.  相似文献   
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The Anatolian ground squirrel (Spermophilus xanthoprymnus) is a typical example of true mammalian hibernators. In order to adapt to extreme external and internal environments during hibernation, they lower their body temperatures, heart rates and oxygen consumption; however, pathological events such as ischemia and ventricular fibrillation do not occur in their cardiovascular systems. During the hibernation, maintenance of cardiac function is very important for survival of ground squirrels. Natriuretic peptides (NPs) are key factors in the regulation of cardiovascular hemostasis. Since NPs’ role on the protection of heart during hibernation are less clear, the aim of this study was to investigate dynamic changes in NPs content in the cardiac chambers and to reveal the possible role of NPs on establishing cardiac function in ground squirrel during hibernation using immunohistochemistry. The immunohistochemical results indicate that cardiac NP expressions in atrial and ventricular cardiomyocytes were different from each other and were sex-independent. ANP and BNP were expressed in a chamber-dependent manner in female and male squirrel hearts. Furthermore, cardiac NPs expression levels in hibernation period were lower than those at the pre-hibernation period. During prehibernation period, ANP, BNP and CNP were expressed in the white and beige adipocytes of epicardial adipose tissue (EAT); while during hibernation period, the brown adipocytes of EAT were positive for BNP and CNP. These data suggest that the hibernation-dependent reduction in levels of NPs, particularly ANP, in cardiac chambers and EAT may be associated with low heart rate and oxygen consumption during hibernation. However, further studies are needed to better delineate the roles of NPs during the hibernation.

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9.
Production and characterization of films from cotton stalk xylan   总被引:1,自引:0,他引:1  
Composite film production based on cotton stalk xylan was studied, and the mechanical and physical properties of the films formed were investigated. Xylan and lignin were separated from cellulose by alkali extraction and, then, lignin was removed using ethanol washing. Self-supporting continuous films could not be produced using pure cotton stalk xylan. However, film formation was achieved using 8-14% (w/w) xylan without complete removal of lignin during xylan isolation. Keeping about 1% lignin in xylan (w/w) was determined to be sufficient for film formation. Films were produced by casting the film-forming solutions, followed by solvent evaporation in a temperature (20 degrees C) and relative humidity (40%) controlled environment. The elastic modulus and hypothetical coating strength of the films obtained by using 8% xylan were significantly different from the ones containing 10-14% xylan. The water vapor transfer rates (WVTR) decreased with increasing xylan concentration, which made the films thicker. The glycerol addition as an additional plasticizer resulting in more stretchable films having higher WVTR and lower water solubility values. As a result, film production was successfully achieved from xylan, which was extracted from an agricultural waste (cotton stalk), and the film-forming effect of lignin on pure xylan has been demonstrated.  相似文献   
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ObjectiveTo determine the optimal dose, serum concentrations and analgesic effects of intravenous (IV) tramadol in the horse.Study designTwo-phase blinded, randomized, prospective crossover trial.AnimalsSeven horses (median age 22.5 years and mean weight 565 kg).MethodsHorses were treated every 20 minutes with incremental doses of tramadol HCl (0.1–1.6 mg kg?1) or with saline. Heart rate, respiratory rate, step frequency, head height, and sweating, trembling, borborygmus and head nodding scores were recorded before and up to 6 hours after treatment. In a second study, hoof withdrawal and skin twitch reflex latencies (HWRL and STRL) to a thermal stimulus were determined 5 and 30 minutes, and 1, 2, 4 and 6 hours after bolus IV tramadol (2.0 mg kg?1) or vehicle. Blood samples were taken to determine pharmacokinetics.ResultsCompared to saline, tramadol caused no change in heart rate, step frequency or sweating score. Respiratory rate, head height, and head nodding and trembling scores were transiently but significantly increased and borborygmus score was decreased by high doses of tramadol. Following cumulative IV administration of 3.1 mg kg?1 and bolus IV administration of 2 mg kg?1, the elimination half-life of tramadol was 1.91 ± 0.33 and 2.1 ± 0.9 hours, respectively. Baseline HWRL and STRL were 4.16 ± 1.0 and 3.06 ± 0.99 seconds, respectively, and were not significantly prolonged by tramadol.Conclusion and clinical relevanceIV tramadol at cumulative doses of up to 3.1 mg kg?1 produced minimal transient side effects but 2.0 mg kg?1 did not provide analgesia, as determined by response to a thermal nociceptive stimulus.  相似文献   
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