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91.
The cytotoxic effects of seven constituents isolated from Duguetia glabriuscula were evaluated against Hep2 human larynx carcinoma cells. The cytotoxicity exhibited by beta-sitosterol was as strong as that of cis-platin. (+)-Alloaromadendran-10,14beta-diol caused inhibition of cellular growth with IC50 values lower than 25 microg/ml, a feature that was considered as revealing significant activity. Polycarpol showed borderline cytotoxicity, whereas the other compounds were inactive.  相似文献   
92.
Culex quinquefasciatus (the southern house mosquito) is an important mosquito vector of viruses such as West Nile virus and St. Louis encephalitis virus, as well as of nematodes that cause lymphatic filariasis. C. quinquefasciatus is one species within the Culex pipiens species complex and can be found throughout tropical and temperate climates of the world. The ability of C. quinquefasciatus to take blood meals from birds, livestock, and humans contributes to its ability to vector pathogens between species. Here, we describe the genomic sequence of C. quinquefasciatus: Its repertoire of 18,883 protein-coding genes is 22% larger than that of Aedes aegypti and 52% larger than that of Anopheles gambiae with multiple gene-family expansions, including olfactory and gustatory receptors, salivary gland genes, and genes associated with xenobiotic detoxification.  相似文献   
93.
陈永红 《种子科技》2022,(5):118-120
油松是三北地区重要的造林树种,能够适应大陆性气候,具有极强的抗寒能力.目前,油松已被引入城市园林绿化工程建设中.为扩大油松种植规模、优化生态、美化城市环境,文章探讨了油松大田容器育苗技术,阐述了容器育苗技术基本流程与技术要点,从前期准备、育苗期处理、后期管理方面介绍关键技术内容,以期为相关人员提供一定的参考与借鉴.  相似文献   
94.
Effects of milk replacer composition and intake on the growth of orphan foals were evaluated. Twenty foals were assigned to four treatments: 1) mare-nursed, 2) commercial foal milk replacer at recommended intakes (standard), 3) commercial foal milk replacer at high intakes (high), and 4) acidified replacer at recommended intakes (acidified). Foals fed milk replacer diets were weaned at 12-24 hours postpartum and fed milk replacer for 50 days. Mare-nursed foals were weaned between 52 and 56 days of age. Foals fed replacer diets gained 12% to 28% less weight than mare-nursed foals up to two weeks of age. However, by four months of age, weights of replacer-fed foals were similar to those of mare-nursed foals and 32 other mare-nursed foals at the farm weaned between three and four months postparium. Foals drank 10 to 12 L/100 kg body weight (BW) in fluid replacer daily over the trial period. During the first week, high intake foals consumed 26% more replacer (p<0.05) than foals fed acidified or standard diets. This higher intake resulted in diarrhea earlier (6-11 days vs 11-22 days) and for a longer time (6.3 days vs 2.5-3.6 days) than in foals fed recommended amounts. Mare-nursed foals developed “foal heat scours” in the second week postpartum. After the first week, foals fed high replacer diet voluntarily consumed the same volume of fluid replacer as foals fed the standard intake. Foals ate less than 1 kg grain mix/100 kg BW daily to one month of age, then increased intake to 1.5-2 kg/ 100 kg BW to weaning. Water intake was 20-40% of daily fluid intake and was correlated (r = 0.85) to dry matter intake. Foals in the high intake group ate less (p<0.05) solid feed and drank less water than foals fed the standard and acidified diets. The foal's stomach capacity appears to limit meal size and thus replacer intake. If recommended feeding intervals are used, replacer intakes by foals are less than 15% BW daily. High volume intakes appeared to prolong diarrhea. Normal growth rates occur when replacer and good-quality feeds are fed concurrently.  相似文献   
95.
Seven cases of idiopathic Horner's Syndrome in the Collie are described. Five males and two females presented with unilateral miosis, ptosis of the upper eyelid, enophthalmos and protrusion of the third eyelid. Thorough examination, pharmacological testing with phenylephrine, complete blood counts and radiography of the tympanic bullae and thorax were performed. The etiology was not identified in any of the cases. Clinical signs improved with pharmacologic testing within 20–40 min. In five dogs, total resolution of clinical signs was observed at 4 and 16 weeks after their initial appearance. Pharmacological testing suggested that the deficit could be at the preganglionic neuron.  相似文献   
96.
Primary and secondary copper deficiency has been identified in most Canadian provinces. Research has been done investigating the environmental and dietary factors that influence dietary copper availability and the effect of deficient copper status on the health and production of cattle. Across Canada, a high percentage of forages and grains are marginal to deficient in copper. In certain regions, high sulphates in the water and/or high molybdenum concentrations in the feed decrease dietary copper availability. The value of various oral and parenteral copper supplements in the treatment and prevention of copper deficiency is discussed.  相似文献   
97.
<正>我省试水农业信用担保,探索"财政、金融联动支农"新模式,通过担保"贷"动农业现代化。2010年,湖南农业信用担保有限公司实现担保融资8亿元,支持农业产业化龙头企业解决融资难题。中小企业融资难,"农"字号中小企业融资更  相似文献   
98.
<正>茄子是夏秋主要蔬菜之一,但夏秋栽培易发生各种病虫害,特别是近年来随着设施园艺的发展,温室、连栋大棚、大棚等设施周年生产,白粉虱、烟粉虱等病虫害发生加重,防治难度加大,大量用药普遍,不但增加成本,还严重影响茄子的品质。为解决这一问题,2005~2007年我市推广茄子  相似文献   
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