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1.
Preparations derived from plants were the original therapeutic interventions used by man to control diseases (including parasites), both within humans and livestock. Development of herbal products depended upon local botanical flora with the result that different remedies tended to develop in different parts of the world. Nevertheless, in some instances, the same or related plants were used over wide geographic regions, which also was the result of communication and/or the importation of plant material of high repute. Thus, the Nordic countries have an ancient, rich and diverse history of plant derived anthelmintic medications for human and animal use. Although some of the more commonly used herbal de-wormers were derived from imported plants, or their products, many are from endemic plants or those that thrive in the Scandinavian environment. With the advent of the modern chemotherapeutic era, and the discovery, development and marketing of a seemingly unlimited variety of highly efficacious, safe synthetic chemicals with very wide spectra of activities, herbal remedies virtually disappeared from the consciousness--at least in the Western world. This attitude is now rapidly changing. There is a widespread resurgence in natural product medication, driven by major threats posed by multi-resistant pest, or disease, organisms and the diminishing public perceptions that synthetic chemicals are the panacea to health and disease control. This review attempts to provide a comprehensive account of the depth of historical Nordic information available on herbal de-wormers, with emphasis on livestock and to provide some insights on potentially rewarding areas of "re-discovery" and scientific evaluation in this field.  相似文献   
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Summary Oven dried basswood was vacuum impregnated with methyl methacrylate monomer containing various amounts of free radical catalyst and trifunctional crosslinking agent. The wood-monomer composite was polymerized at 60°C in an air oven and the rate of heat generated was followed by means of a thermocouple placed in the center of the sample.Increasing the concentration of Vazo free radical catalyst in the basswood-MMA impregnated samples reduces the time to the exothermic peak and increases the exothermic peak temperature. High Vazo concentrations also decraase the percentage conversion of monomer to polymer.Trimethyl propane trimethacrylate (TMPTMA) crosslinker reduces the time to the exothermic peak and dramatically increases the exothermic peak temperature. The use of a crosslinker rapidly increases the initial viscosity of the system, and therefore, the autoacceleration of the polymerization is more pronounced.Our thanks are due to DuPont Company and Sartomer Resins for supplying the monomers and catalysts. Research funds were provided by Organized Research Budget of the College of Forestry.  相似文献   
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为了探索烟叶生产过程中各机械的性能及工作效率,2013年在福建省建阳市莒口镇河坝新村开展了烟叶生产全程机械化作业试点研究。结果表明,起垄环节,碎土率方面邵武华友履带式起垄机表现最好(89.9%),沟底积土方面松溪永顺表现最好;覆膜环节,各测试机型表现中等,在效率方面优于人工覆膜;移栽环节,漏栽率上江苏久泰移栽机高于江苏井关移栽机;培土环节,漳州南冠培土机操作简便,掉头灵活,单人操作,单行双侧作业,深受烟农喜爱;拔杆环节,龙岩诚德拔杆机单人操作,操作简便,动力较足,拔杆顺畅,拔杆带土较少,效果较好,适应性较强。  相似文献   
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Both NO and N2O are produced in soil microbial processes and have importance in atmospheric physics and chemistry. In recent years several studies have shown that N2O emissions from organic soils can be high at low temperatures. However, the effects of low temperature on NO emissions from soil are unknown. We studied in laboratory conditions, using undisturbed soil cores, the emissions of NO and N2O from organic soils at various temperatures, with an emphasis on processes and emissions during soil freezing and thawing periods. We found no soil freezing- or thawing-related emission maxima for NO, while the N2O emissions were higher both during soil freezing and thawing periods. The results suggest that different factors are involved in the regulation of NO and N2O emissions at low temperatures.  相似文献   
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This paper analyzes the genetic diversity of mashua cultivars grown in six communities in the Cusco region of Perú, of non-cultivated forms collected in the same region, and a sample of cultivars from the germplasm collection at the International Potato Center (CIP). From the DNA fingerprinting generated by SRAP markers, it is clear that mashua is a genetically variable crop with a range of similarity ranging from 65 to 99%. The widest range of variation was found for the most isolated community, Sayllafaya. Another important finding was that most of the non-cultivated accessions are likely feral races resulting from escape to cultivation rather than wild relatives. In general the range of variation of the cultivars from the communities and their feral relatives are not represented in the cultivars sampled of the collection maintained at the International Potato Center, Perú.  相似文献   
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Pharmacokinetics of phenobarbital in the horse   总被引:2,自引:0,他引:2  
Pharmacokinetics of phenobarbital was examined in 6 mature horses after 12 mg of phenobarbital/kg of body weight was infused over 20 minutes. Biexponential decrease in serum phenobarbital concentrations was observed with a distribution-phase half-life of 0.101 +/- 0.086 hour (mean +/- SD) and a terminal-phase elimination half-life of 18.3 +/- 3.65 hours. The volume of distribution at steady state was 0.803 +/- 0.070 L/kg. Total body clearance of phenobarbital was 30.8 +/- 6.2 ml/h/kg. The high clearance in the horse seems to explain the markedly shorter half-life of phenobarbital in this species. Seemingly, 6.65 mg of phenobarbital/kg as a 20-minute infusion given every 12 hours would provide approximate peaks of 29 micrograms/ml and troughs of 15 micrograms/ml. A loading dose of 12 mg of phenobarbital/kg would be appropriate for this regimen.  相似文献   
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In the cows of the whole group under study, a significant negative relation (r = = -0.4797) was found between the histidine level in arterial blood and protein content in milk; further, there was a significant positive relation (r = 0.4624) between alanine level in milk and protein content in milk, and a significant negative relation (r = -0.5028) for the level of threonine. The group of cows with a higher milk output showed a significant negative relation between methionine level in milk and protein content in milk (r = -0.7482) and a highly significant negative relation between threonine level and protein content in milk (r = -0.8410). The negative relations of some amino acids to the content of protein in milk suggest that there is a poor supply of these amino acids for the production of protein in milk.  相似文献   
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