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Drawn on the data col ected by surveying 1 340 urban households from six cities in China, this paper estimates the impacts of demographic structure and population aging on household meat consumption, b... 相似文献
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根据新时期高校安全保卫工作的新要求,重新定位当今高校保卫工作,提出高校安全工作要坚持预防为主,防治结合的原则.随着高等教育的事业的持续发展和高校内部的一系列政策的不断深化,安全稳定工作也遇到了许多新情况、新问题.分析了预防为主原则的概念、特点及重要性,阐述了预防为主的环境因素,并提出了预防为主的几点建议,使学校安全保卫... 相似文献
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Drawn on the data collected by surveying 1 340 urban households from six cities in China, this paper estimates the impacts of demographic structure and population aging on household meat consumption, by jointly considering meat consumed at home and away from home. Based on the trajectories of population, a simple simulation on meat demand trend in China is conducted subsequently. The results suggest: 1) Meat consumed away from home averagely accounts for near 30% of household total meat consumption in terms of quantity, so that its omission likely leads to a significant underestimate of total meat consumption and misunderstanding the driving forces; 2) population aging significantly and negatively affects per capita meat consumption, suggesting that the expected meat demand in China without considering population aging will be overestimated. The findings from this study have important implications for better understanding the relative issues on China's meat consumption under the situation of population aging. 相似文献
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盐碱井灌稻区抛秧水稻生育性状及产量研究 总被引:8,自引:4,他引:4
研究了水稻抛秧栽培技术在吉林省西部盐碱井灌区应用效果。试验结果表明,水稻抛秧栽培产量可达7683.8kg/hm^2,比旱育苗人工插秧提高8.8%,提早成熟5天,并具有秧苗素质好、分蘖多、成熟早、产量高、成本低、省工省时等优点,可解决盐碱冷浆寺区水稻插秧缓苗慢、插秧适期短等生产问题。 相似文献
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E.S. Rosenblum T.T. Robbins B.B. Scott S. Nelson C. Juhasz A. Craigmill R.S. Tjeerdema J.D. Moore C.S. Friedman 《Aquaculture (Amsterdam, Netherlands)》2008,277(3-4):138-148
Oxytetracycline (OTC) was recently demonstrated to be an effective therapeutant for California red abalone (Haliotis rufescens) infected with the agent of withering syndrome (WS), a Rickettsia-like prokaryote (WS-RLP). This study examined the influence of temperature on the efficacy and pharmacokinetics of oral OTC treatments on WS-RLP infected red abalone, H. rufescens. Medication was administered in an artificial diet containing 1.85% active OTC at a rate of 103.4 mg/kg abalone for 10, 20 and 30 days at both 13.4 °C and 17.3 °C. Drug residue concentrations, WS-RLP burden and WS-associated pathological changes within foot muscle and digestive gland were measured 3, 17, 23, 42, 63, 81, 102, 122, and 160 days after OTC treatment. In all samples the highest concentrations of OTC were detected on the first sample day. Furthermore, all sampling periods showed significantly less OTC in foot muscle samples relative to corresponding digestive gland samples (p < 0.001). While drug depuration occurred rapidly from foot muscle, unusually high concentrations and long depuration times were measured within the digestive gland. The pharmacokinetic trends in both the foot muscle and digestive gland at 13.4 °C were adequately described by a one-compartment model, while the digestive gland depuration models within the 17.3 °C treatments conformed to a two-compartment model. At both temperatures treatment duration gave rise to significant differences in OTC accumulation and depletion (p < 0.001). Despite this, terminal elimination rate constants were similar. Estimated half-lives were similar among all treatments for digestive gland (23.8–27.5 d) and all treatments for the foot muscle at 13.4 °C (10.7–13.4 d; calculated only for the 13.4 °C treatments). At both temperatures all three durations of drug treatment led to significant reductions in WS-RLP prevalence, foot muscle atrophy, and mortality. WS-RLP re-challenge trials initiated 44, 88, and 122 days following the 10-day treatment at 17.3 °C showed reduced susceptibility to re-infection for up to 88 days after treatment, suggesting that digestive gland OTC residues confer long-term resistance to pathogen. Atomic absorption spectroscopy conducted on both foot muscle and digestive gland found significantly higher concentrations of iron, zinc, and manganese in the digestive gland, offering an explanation behind the underlying mechanism of OTC retention for extended periods within this tissue. 相似文献
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农村金融市场资金供给不足已成为我国新农村建设的制约因素,大量金融机构撤离农村,现代金融体系已无法适应农村经济的现状,新型的农村金融体系亟需建立。文章分析农村金融市场长期供给不足的原因,提出增强农村金融市场资金供给的一些建议。 相似文献