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91.
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Nan‐Xi Hu Mei Chen Yi‐Song Liu Qi Shi Bo Yang Huan‐Cheng Zhang Pi Cheng Qi Tang Zhao‐Ying Liu Jian‐Guo Zeng 《Journal of veterinary pharmacology and therapeutics》2019,42(2):197-206
Sanguinarine (SA) and chelerythrine (CHE) are the main active components of the phytogenic livestock feed additive, Sangrovit®. However, little information is available on the pharmacokinetics of Sangrovit® in poultry. The goal of this work was to study the pharmacokinetics of SA, CHE, and their metabolites, dihydrosanguinarine (DHSA) and dihydrochelerythrine (DHCHE), in 10 healthy female broiler chickens following oral (p.o.) administration of Sangrovit® and intravenous (i.v.) administration of a mixture of SA and CHE. The plasma samples were processed using two different simple protein precipitation methods because the parent drugs and metabolites are stable under different pH conditions. The absorption and metabolism of SA following p.o. administration were fast, with half‐life (t1/2) values of 1.05 ± 0.18 hr and 0.83 ± 0.10 hr for SA and DHSA, respectively. The maximum concentration (Cmax) of DHSA (2.49 ± 1.4 μg/L) was higher that of SA (1.89 ± 0.8 μg/L). The area under the concentration vs. time curve (AUC) values for SA and DHSA were 9.92 ± 5.4 and 6.08 ± 3.49 ng/ml hr, respectively. Following i.v. administration, the clearance (CL) of SA was 6.79 ± 0.63 (L·h?1·kg?1) with a t1/2 of 0.34 ± 0.13 hr. The AUC values for DHSA and DHCHE were 7.48 ± 1.05 and 0.52 ± 0.09 (ng/ml hr), respectively. These data suggested that Sangrovit® had low absorption and bioavailability in broiler chickens. The work reported here provides useful information on the pharmacokinetic behavior of Sangrovit® after p.o. and i.v. administration in broiler chickens, which is important for the evaluation of its use in poultry. 相似文献
93.
中国狗牙根染色体数变异研究初报 总被引:11,自引:4,他引:11
通过国内30份狗牙根种源当色体数目的观测分析.结果表明,①我国狗牙根种质资源染色体数目呈现非常高的异质性,不同种源具有不同染色体数,同一种源不同根尖存在不同染色体数,同一根尖不同细胞亦具备不同染色本数,不同倍性平均出现的频率依次为:4n(32.26%)>n(18.98%)>3n(10.7%)>6n(2.13%)>2n(0.41%).此外,非整倍体平均比率高达32.1%.②染色体数目与纬度、经度、海拔间均无显著回归关系.该项研究为我国狗牙根种质资源开发利用提供了初步的试验依据. 相似文献
94.
通过对草产业集群的经济功效与形成路径的研究,认为虽然产业集群一般都是自发形成的,但政府培育仍然可以发挥出较好的引导效果.论文同时对政府引导产业集群形成的路径进行了探讨. 相似文献
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96.
A biological attack on livestock or poultry could result in the loss of valuable animals, costs related to the containment of outbreaks and the disposal of carcasses, lost trade and other economic effects involving suppliers, transporters, distributors and restaurants; however, it is not possible to secure all livestock, and livestock are much less well guarded than human targets. Thus, the vulnerability of the livestock industry to the introduction of biological agents varies for the following reasons: (i) the majority of lethal and contagious biological agents are environmentally resilient, endemic in foreign countries and harmless to humans, making it easier for terrorists to acquire, handle and deploy these pathogens, (ii) with animals concentrated in fewer production facilities and frequently transported between these facilities, a single pathogen introduction could cause widespread infection and (iii) the extent of human travel around the globe makes it difficult to exclude exotic animal diseases as possible biological agents. Historically, many governments have developed and planned to use biological agents for direct attacks on livestock or poultry. In the past, developed nations have actively developed biological weapons to target animals. The potential spectrum of bioterrorism ranges from isolated acts against individuals by individuals to tactical and strategic military attacks and state‐sponsored international terrorism intended to cause mass casualties in animals, humans or both. This review provides an overview of the past development and use of biological weapons and describes potential future attacks. 相似文献
97.
98.
不同遮荫强度对草地早熟禾草坪质量的影响 总被引:1,自引:0,他引:1
为研究不同遮荫强度对新建草地早熟禾(Poa pratensis)草坪生长状况的影响,于2009年5月1日-11月6日进行试验,共设计自然光照、轻度遮荫、中度遮荫和重度遮荫4种不同遮荫强度,对干旱胁迫下草地早熟禾的生长速率、草坪质量、草屑重量、叶色值、电导率和地下生物量等形态指标和生理指标进行观察测定。结果表明,在少雨时节中度遮荫的草坪质量较高,多雨时节则轻度遮荫的草坪质量较好;适度遮荫下草坪草的生长正常,叶色较好,电导率较小,草坪质量较高。因此,可以利用适度遮荫,减少夏季高温与干旱对草地早熟禾草坪的伤害,改善草坪质量。 相似文献
99.
100.