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31.
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
32.
孕牛血清中早孕因子的分离纯化 总被引:2,自引:0,他引:2
采用DEAE-Sepharose(DEAE-琼脂糖凝胶)、CM-Sepharose(CM-琼脂糖凝胶)等离子交换层析、抗孕牛全血清IgG-Sepharose 4B亲和层析等技术,分离纯化妊娠4-5个月健康孕牛全血清中的早孕因子(EPF),用玫瑰花环抑制实验对各阶段产物EPF活性进行检测。结果表明,经层析过柱后的CM-ⅡA提取物有EPF活性。经SDS-PAGE银染显色证实它含有分子量为21、67、80KD的蛋白,实验结果支持21KD的多肽为主要EPF活性物成分。同时实验表明了亲和层析对进一步纯化EPF是可行的。 相似文献
33.
为鉴定男性不育药和有些驱虫药对寄生蠕虫的不育作用,对培养在试管内的鸡蛔虫和卵胚,以及人工感染蛔虫的鸡分别进行了体内和体外试验。棉酚和硝基呋喃类的呋喃唑酮、呋喃西林、S_(73031)和S_(72055)均无抑制产卵和卵胚发育的作用,苯并咪唑类的丙硫咪唑、甲苯咪唑和噻苯咪唑以及吩噻嗪均有抑制产卵和卵胚发育的作用,它们的EMIC_(50)分别为0.006,1.326,0.029和0.052ppm。抑制产卵所需浓度远大于抑制卵胚发育所需浓度。吡喹酮和硫双二氯酚也不具有抑制产卵和卵胚成熟的作用。放线菌酮仅对试管内蛔虫有抑制产卵作用,但对体内蛔虫却无影响。 相似文献
34.
35.
自然感染日本血吸虫病耕牛血清循环抗原消长规律的研究 总被引:1,自引:0,他引:1
为了观察疫区自然感染日本血吸虫病耕牛血清循环抗原消长规律,本试验将血吸虫病非疫区的水、黄牛各10头,转运至安徽省血吸虫病疫区,接受为期8周的自然感染。用斑点酶联免疫吸附试验测定牛血清循环抗原。结果,水、黄牛血清循环抗原滴度均于自然感染第4周后明显上升,水、黄牛自然感染第8周的血清循环抗原最高滴度分为1∶10240和1∶5120,最低滴度则分别为1∶1280和1∶640,水牛循环抗原滴度高于黄牛。虫荷数与血清循环抗原滴度未见有相关性。 相似文献
36.
鸡丘脑背外侧核前部与上纹状体、新纹状体、外纹状体及圆核和视顶盖有纤维交互投射;丘脑背外侧核后部与上纹状体、新纹状体及圆核和视顶盖有纤维交互投射,且与丘脑其他核团有较多的联系。 相似文献
37.
38.
Weng Q Shi Z Kawaguchi M Watanabe G Taya K 《The Journal of reproduction and development》2008,54(5):397-401
Characteristic daily increases in the plasma levels of luteinizing hormone (LH) are present every afternoon during lactation in golden hamsters. The objective of this study was to investigate the effect of the diurnal rhythm of increases in LH on expression of nerve growth factor (NGF), its receptors trkA and p75 and inhibin alpha-subunit in the ovarian interstitial cells of lactating golden hamsters. Both lactating and non-lactating groups of postpartum golden hamsters were used in this study. The expression of NGF, its receptors trkA and p75 and inhibin alpha-subunit were determined by immunohistochemistry. Positive staining of NGF, trkA and p75 was found in the interstitial cells of the lactating group, and no immunoreactivity for NGF, trkA or p75 was observed in the ovarian interstitial cells of the non-lactating group. In addition, immunostaining of inhibin alpha-subunit was also observed in the interstitial cells of the lactating group but not in those of the non-lactating group. Immunostaining of the inhibin/activin beta(A)- and beta(B)-subunits was observed in the granulosa cells of antral follicles, but not in the interstitial cells of the lactating and non-lactating animals. These results suggest that the diurnal rhythm increases in LH can induce expression of NGF, trkA, p75 and inhibin alpha-subunit in the ovarian interstitial cells of lactating golden hamsters and that NGF, its receptors trkA and p75 and inhibin alpha-subunit may have the capacity for autocrine or paracrine modulation of interstitial cell differentiation in golden hamsters. 相似文献
39.
乳牛舍内环境空气中细菌数量与乳房炎的关系研究 总被引:2,自引:1,他引:2
采用自然沉降法对规模化泌乳奶牛舍内消毒前后空气细菌含量进行检测,同时对泌乳牛群进行乳房炎调查,对乳房炎奶牛乳汁中病原菌分离鉴定。结果表明,不同的牛舍不同的培养基其结果均不相同,NA培养基菌落数最高达77.8×103cfu/m3,S.S培养基在多个分布点无细菌生长。牛舍经过消毒后环境空气中的细菌总数大幅度减少,运动场空气细菌总数明显低于舍内。奶牛乳房炎的发生率与牛舍环境空气中的细菌总数呈正相关,细菌总数多的牛舍奶牛乳房炎的发病率也高。环境空气中和乳房炎奶牛乳汁中同时分离到金黄色葡萄球菌、大肠杆菌、伤寒沙门氏菌、肺炎克雷伯氏菌等。 相似文献
40.
Mengjie Zheng Zesheng Li Xinyu Fu Qian Lv Yang Yang Fushan Shi 《Journal of veterinary science (Suw?n-si, Korea)》2021,22(5)
BackgroundFeline calicivirus (FCV) is a common pathogen of felids, and FCV vaccination is regularly practiced. The genetic variability and antigenic diversity of FCV hinder the effective control and prevention of infection by vaccination. Improved knowledge of the epidemiological characteristics of FCV should assist in the development of more effective vaccines.ObjectivesThis study aims to determine the prevalence of FCV in a population of cats with FCV-suspected clinical signs in Hangzhou and to demonstrate the antigenic and genetic relationships between vaccine status and representative isolated FCV strains.MethodsCats (n = 516) from Hangzhou were investigated between 2018 and 2020. The association between risk factors and FCV infection was assessed. Phylogenetic analyses based on a capsid coding sequence were performed to identify the genetic relationships between strains. In vitro virus neutralization tests were used to assess antibody levels against isolated FCV strains in client-owned cats.ResultsThe FCV-positive rate of the examined cats was 43.0%. Risk factors significantly associated with FCV infection were vaccination status and oral symptoms. Phylogenetic analysis revealed a radial phylogeny with no evidence of temporal or countrywide clusters. There was a significant difference in the distribution of serum antibody titers between vaccinated and unvaccinated cats.ConclusionsThis study revealed a high prevalence and genetic diversity of FCV in Hangzhou. The results indicate that the efficacy of FCV vaccination is unsatisfactory. More comprehensive and refined vaccination protocols are an urgent and unmet need. 相似文献