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21.
A low-resolution gas-phase FT-IR method for the fast analysis of supercritical CO2-extracted caraway fruit oils has been developed. The limonene/carvone ratio of extraction product was determined within seconds, yielding a coefficient of variation of <5% (n = 10). A selection of experimental parameters is discussed on the basis of the analysis of 52 extracted samples. GC-FID was used as a reference method. A correlation of 0.983 (n = 24) between the two methods was observed. This method is suitable for the analysis of a large number of caraway fruit extracts due to its speed, repeatability, and minimum sample preparation.  相似文献   
22.
OBJECTIVE: To evaluate clinical response, pulmonary function, and adrenal gland response to incremental doses of beclomethasone dipropionate in horses with recurrent airway obstruction. DESIGN: Crossover trial. ANIMALS: 8 horses with recurrent airway obstruction. PROCEDURE: Horses randomly assigned to 4 groups were treated twice daily via aerosol administration of placebo or 500, 1,000, or 1,500 micrograms of beclomethasone dipropionate in a crossover design with a 10-day minimum washout period. Subjective assessment of airway obstruction, serum cortisol concentration, and maximum change in pleural pressure during tidal breathing (delta Pplmax) were determined daily prior to morning drug administration, and delta Pplmax was reevaluated 15 minutes after morning drug administration. Pulmonary resistance and dynamic compliance were determined at baseline and approximately 12 hours after the final treatment. RESULTS: An immediate treatment effect was not identified. Within 24 hours, delta Pplmax and airway obstruction were lower in horses receiving beclomethasone. Onset and magnitude of response was similar among the 3 beclomethasone dose regimens. Pulmonary resistance was improved only after administration of all 3 doses of beclomethasone, whereas dynamic compliance was improved after administration of 1,000 micrograms and 1,500 micrograms of beclomethasone. Reduction in serum cortisol concentration occurred with all 3 beclomethasone dose regimens; however, the magnitude of adrenal gland suppression was greater in horses receiving 1,000 or 1,500 micrograms of beclomethasone. CONCLUSIONS AND CLINICAL RELEVANCE: Low-dose (500 micrograms) beclomethasone administration caused similar, improvement in pulmonary function, compared with high-dose beclomethasone (1,000 and 1,500 micrograms), with the exception of dynamic compliance, and caused less suppression of endogenous cortisol production.  相似文献   
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24.
Interspecific somatic hybrids produced by protoplast fusion between two wild Solanum species (S. acaule, acl; S. brevidens, brd) and cultivated potato Solanum tuberosum (tbr) were analyzed in terms of the starch nanometer-range structure and glycoalkaloid (GA) contents. The crystallinity of starch granules, the average size of starch crystallites, and the lamellar distances were obtained from tuber samples using wide-angle and small-angle X-ray scattering methods. These measurements showed that incorporation of wild genomes from either nontuberous (brd) or tuberous (acl) Solanum species caused no significant modifications of the nanostructure of potato starch. In contrast, the GA profiles of the hybrids, which were analyzed by LC-ESI-MS in both tuber and foliage samples, differed considerably from those of cultivated potato. Regardless of the low total tuber GA concentrations (approximately 9 mg/100 g of fresh weight), the somatic hybrids contained GAs not detected in the parental species. A high proportion of spirotype GAs consisting of 5,6-dihydrogenated aglycons, for example, alpha-tomatine and tomatidine bound with solatriose, and chacotriose were found in the hybrids. In conclusion, the foliage of interspecific hybrids contained a higher variation in the structures of GAs than did the tubers.  相似文献   
25.
OBJECTIVE: To determine the dose of aerosolized albuterol sulfate required to cause bronchodilation in horses with recurrent airway obstruction (RAO) and duration of this effect. ANIMALS: 19 horses with RAO (10 in experiment 1; 9 in experiment 2). PROCEDURE: Horses were moved from pasture to stables, and airway obstruction was induced. Pulmonary function was measured in 10 horses before and 5, 10, and 30 minutes after administration of vehicle or 120, 240, 360, or 720 microg of the drug. Nine horses received vehicle or 360 or 720 microg of albuterol, and pulmonary function was measured at baseline and 5 minutes and 1, 2, 3, 4, 5, 6, and 7 hours later. Horses were evaluated for adverse drug effects. RESULTS: 360 microg of albuterol was required to cause significant bronchodilatation; 720 microg did not enhance bronchodilatation or increase duration of action. Depending on which pulmonary function parameter was evaluated, bronchodilatation achieved by use of albuterol lasted between 30 minutes and 1 hour. Because there was a significant vehicle effect, the combined effect of vehicle and drug lasted up to 3 hours. Adverse effects were not observed. CONCLUSIONS: Aerosolized albuterol, 360 or 720 microg, is a safe and effective bronchodilator in horses with RAO. Onset of action is rapid (5 minutes), and effects last from 30 minutes to 3 hours. CLINICAL RELEVANCE: Aerosolized albuterol is useful for treatment of bronchospasm in horses with RAO.  相似文献   
26.
OBJECTIVE: To determine whether pulmonary distribution of aerosolized technetium Tc 99m pentetate is improved after inhalation of a single dose of albuterol sulfate in horses susceptible to recurrent airway obstruction (heaves). ANIMALS: 6 horses with heaves and 4 horses with normal respiratory tract function. PROCEDURE: Images were obtained during ventilation of horses at baseline (maximal change in pleural pressure during tidal breathing [deltaPpImax] >15 cm H2O) and after aerosolized albuterol sulfate (360 microg) administration, with a 24-hour washout period between experiments. The deltaPpImax was determined prior to the baseline scan, prior to albuterol sulfate administration, and 5 minutes after albuterol sulfate administration. Images were assessed by visual inspection (semi-quantitative scoring system) and histogram analysis. RESULTS: Images obtained from horses with heaves had nonuniform pulmonary distribution of radionuclide characterized by poor penetration in peripheral lung fields and excess deposition in large airways. Histogram analysis of images of the caudal portions of the lungs revealed nonuniform radionuclide deposition in horses with heaves and uniform radionuclide deposition in control horses. CONCLUSION: Administration of a single dose of aerosolized albuterol sulfate improved pulmonary distribution of aerosolized radiolabeled pentetate suspension in horses with heaves but did not alter pulmonary distribution in clinically normal horses. CLINICAL RELEVANCE: Precedent bronchodilator administration may improve pulmonary distribution of aerosolized, surface-active anti-inflammatory preparations.  相似文献   
27.
Abstract

Winters are typically harsh in the northernmost agricultural areas of Europe, and winter rye (Secale cereale L.) and wheat (Triticum aestivum L.) are the only winter grain crops that can be grown. However, climate change is projected to result in milder winters, which may enable cultivation of winter crops to a greater extent in the future than is possible today. In this study we aimed at identifying main temperature, precipitation events and characteristics that have resulted in past poor overwintering of rye and wheat in their current production areas in Finland. Using long-term (1970–2006), multi-location datasets, we compared our findings with the projected major changes attributable to climate change. Mixed models were used to estimate mutually comparable overwintering damage to all experiments and logistic regression was used to determine whether climatic parameters are related to high levels of overwintering damage. Severity of overwintering damage, and associated yield penalties, fluctuate considerably on a year-to-year basis and no consistent reduction in variability was recorded during the study period. Particularly for wheat, severity of winter damage in any one year was associated negatively with area sown in the following year. There was no evidence of consistent genetic improvements in winter hardiness, but rye was more winter hardy than wheat. Current risks associated with rye production related to low temperatures could be alleviated in the future, although overwintering damage currently enhanced by high autumn precipitation could increase due to climate change. For wheat, fluctuating conditions hampered overwintering, which may be an even harder challenge in future when weather variation is projected to increase and extreme weather events are projected to become more common.  相似文献   
28.
The deer ked (Lipoptena cervi) is a haematophagous parasitic fly of cervids that spread to Finland in the early 1960's. Presently its northern distribution limit lies at approximately 65°N and it is gradually spreading northwards. In Finland the principal host species has been the moose (Alces alces), but the deer ked is about to establish contact with another potential host, the semi-domesticated reindeer (Rangifer tarandus tarandus) causing possible threats to reindeer health and management. The aim of this study was to investigate if the deer ked would have an influence on the welfare of the reindeer. Eighteen adult reindeer were divided into three experimental groups: the control group and two infected groups with 300 deer keds per reindeer introduced in August-September. One of the infected groups was treated with subcutaneous ivermectin in November. To gather comprehensive data on potential health hazards caused by the deer ked a wide array of physiological variables was measured during and at the end of the experiment in December. The keds caused no clear changes in the complete blood count, plasma clinical chemistry, amino acids, endocrinology, energy stores, enzyme activities or tissue fatty acid profiles of the host. The haematological, clinical chemical and endocrinological values displayed changes that could be related to the seasonal physiological adaptations of the species. In conclusion, at the duration and intensity of infection that were employed, the effects of the deer ked on the measured physiological variables of the reindeer were insignificant.  相似文献   
29.
不同产地沙棘果的成分分析   总被引:2,自引:0,他引:2  
通过沙棘甘油三酯和甘油磷脂中的糖、果酸(气相色谱-质谱法,TMS衍生物)、矿物质(FAAS,ETAAS)、挥发性物质(顶部空间气相色谱-质谱法)、Vc(高压液相色谱)和脂肪酸(气相色谱-质谱法,甲基酯)的分析方法,优化不同产地的沙棘果。对1997年10-11月采集的中国沙棘果(CH)和8月底采集的芬兰沙棘果(FI)和俄罗斯沙棘果(RU)的成分进行比较,得到了为今后开展更广泛的沙棘项目所需要的足够的资料。中国沙棘果汁中的Vc含量极高,平均8g/l(4.2-13.2g/l),是芬兰沙棘果汁中含量的5倍。主要矿物元素的含量比其它可食用的浆果中丰富得多,钾是沙棘果(6-14g/kg,干重)和沙棘籽(5-9g/kg,干重)中的主要矿物质之一,在一些样品中铅和镉含量的增加表明存在轻微的污染。压榨的沙棘果汁中糖的含量从1-20g/100ml有很大的变化,含量最高的是晚秋收获的中国沙棘果,最低的是8月收获的芬兰沙棘果。糖主要是葡萄糖(占总糖分的50%以上)、果糖及葡萄糖衍生物。苹果酸和奎宁酸是主要的果酸(77%-97%),含量为每100ml果汁中4.2-9.1g。果汁上部油脂的特点是形成了C2-C5n-、iso-、和ante-iso乙醇,C4-C5n-,iso,及ante-ISO酸,也呈现出挥发性油脂的籽油乙醇前体。不同的产地和采收时间对挥发物有着明显的影响,整个果中的含油量为2%-11%(鲜重),籽中的含  相似文献   
30.
Water is the primary regulator of yield formation in cereals. The effect of water limitation and its timing on development of yield components were studied in detail at spike and spikelet level in spring barley (Hordeum vulgare L.). An experiment with three watering treatments (control watering, CONT; drought prior to pollination, DR1 and terminal drought, DR2) was set up in a large greenhouse (20 × 30 m). In addition to watering treatments, two NPK fertilizer application rates (0 and 120 kg N ha?1) were used to investigate the fertilizer effect. The drought effect exceeded the effect of fertilizer application for grain number and single grain weight (SGW). DR1 reduced the number of grains, whereas DR2 reduced both SGW and the number of grains. Resuming the watering at pollination (DR1) restored photosynthesis and enhanced grain filling, resulting in almost similar SGW in DR1 and CONT plants. Spikelets in the upper mid‐section of the spike dominated yield formation in all treatments. This was particularly emphasised in DR1 plants as 58 % of the grain yield was produced in spikelets 3–5, whereas in DR2 and CONT plants it was 39 % and 36 %, respectively. Hence, drought prior pollination strongly reduced yielding capacity (=grain number) in apical and basal spikelets. DR1 and DR2 reduced substantially grain yield and grain N yield resulting in low nitrogen use efficiency.  相似文献   
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