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11.
A. Flåøyen H. Hjorth Tønnesen H. Grønstøl J. Karlsen 《Veterinary research communications》1991,15(6):483-487
It has been suggested that saponins produced by Narthecium ossifragum (Bog asphodel) may be the direct cause of the toxicity leading to the hepatogenous photosensitivity disease alveld seen in Norwegian lambs. Lambs fed large quantities of freeze-dried N. ossifragum did not develop alveld. Chemical investigations on the freeze-dried material and fresh N. ossifragum showed no difference in their saponin content. These results indicate that alveld is not caused solely by the saponins produced by N. ossifragum. 相似文献
12.
Fl∢øyen A. Bratberg B. Frøslie A. Grønstøl H. Langseth W. Mantle P.G. Von Krogh A. 《Veterinary research communications》1997,21(7):499-506
Seven goats were given a single dose of an aqueous extract derived from 30 g (wet weight) of Narthecium ossifragum per kg liveweight. Their serum creatinine and urea concentrations increased to day 5 but then fell to normal by day 10. Serum magnesium increased to day 4 and decreased to normal by day 9. Their serum calcium concentration was lower than normal on days 4, 5 and 6. Histopathological examination of the kidneys of goats killed or found dead 2, 4, 6, 8, 11 or 16 days after dosing revealed tubular epithelial cell degeneration and necrosis. Regeneration of the tubular epithelium and signs of interstitial fibroplast proliferation and fibrosis could be seen in animals killed on days 8, 11, 16 and 42. No signs of liver damage were observed in 3 goats dosed with the insoluble plant material from 40 g (wet weight) Narthecium ossifragum per kg liveweight. The total dose was divided into three doses, which were given intraruminally within 7 h. The activities of aspartate aminotransferase, -glutamyl-transferase and glutamate dehydrogenase remained within the normal range in all 10 goats after dosing. 相似文献
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14.
The detection of 4-hydroxycoumarin rodenticides in poisoned domestic animals requires a highly sensitive method as tissue and serum levels of anticoagulants may be very low owing to rapid elimination, metabolism or post-mortem degradation. Thin-layer chromatography (TLC) and reversed-phase high-performance liquid chromatography (RP-HPLC) with fluorescence detection were used to identify the anticoagulants in spiked tissues and in suspicious samples. The analysis of ten suspicious samples highlighted the limitations of both methods. Only the three samples of baits were found positive by TLC whereas one of the five anticoagulants was detected in eight samples by RP-HPLC with fluorescence detection. Therefore, RP-HPLC with fluorescence detection proved to be the more sensitive method for detecting low levels of 4-hydroxycoumarins in blood serum, liver and ingesta, whereas TLC is usually sufficient for analysing baits.Abbreviations RP-HPLC
reversed-phase high-performance liquid chromatography
- TLC
thin-layer chromatography 相似文献
15.
不同植物油对大规格吉富罗非鱼生长性能、组织脂肪酸组成的影响 总被引:1,自引:0,他引:1
本试验旨在探究大规格吉富罗非鱼(GIFT)对不同植物油的利用效果,筛选出大规格吉富罗非鱼饲料中合适的植物脂肪源。分别以大豆油(SO)、棕榈油(PO)、棉籽油(CO)、菜籽油(RO)、磷脂油(SL)和大豆油∶棕榈油∶棉籽油∶菜籽油∶磷脂油=1∶1∶1∶1∶1的混合油(MIX)为脂肪源配制6种等氮等脂的试验饲料,饲喂初始体重为(229.92±0.31)g的吉富罗非鱼8周。每种试验饲料投喂4个网箱(重复),每个网箱放养50尾。结果表明:对于增重率和特定生长率,棉籽油组和混合油组显著低于菜籽油组(P0.05)。菜籽油组饲料系数显著低于混合油组(P0.05),其他各组间无显著差异(P0.05)。混合油组蛋白质效率显著低于菜籽油组和磷脂油组(P0.05)。混合油组肝体指数显著高于棕榈油组和菜籽油组(P0.05)。大豆油组、菜籽油组、棕榈油组和磷脂油组在增重率、特定生长率和饲料系数方面没有显著差异(P0.05)。大豆油组和菜籽油组肌肉饱和脂肪酸总量显著低于其他各组(P0.05)。对于肌肉中n-3系脂肪酸/n-6系脂肪酸,菜籽油组显著高于其他各组(P0.05),棉籽油显著低于其他各组(P0.05)。棉籽油组肝脏饱和脂肪酸总量显著高于其他各组(P0.05),菜籽油组则显著低于其他各组(P0.05);对于肝脏n-3/n-6,菜籽油组显著高于其他各组(P0.05)。各组肌肉脂肪酸组成与饲料脂肪酸组成的相关系数均高于肝脏脂肪酸组成与饲料脂肪酸组成的相关系数。在饲料脂肪酸组成与肌肉或肝脏脂肪酸组成的相关系数中,均以棕榈油组最大,磷脂油组最小。由此得出,大豆油、棕榈油、菜籽油和磷脂油可以作为大规格吉富罗非鱼(体重为230~790 g)饲料中良好的脂肪源。大规格吉富罗非鱼肌肉中脂肪酸组成一定程度上被饲料脂肪酸组成影响,但肝脏脂肪酸组成与饲料脂肪酸组成的相关性较小。 相似文献
16.
Immune function in dairy cows related to energy balance and metabolic status in early lactation 总被引:1,自引:0,他引:1
Two feeding experiments were carried out in 2 successive years with 28 cows of the Norwegian Red Cattle (NRF) in each experiment. The cows were randomly distributed into 4 groups and subjected to different feeding regimens from 1 month prior to calving until 12 weeks after calving. The experimental design was factorial (2 x 2) with respect to protein content of the concentrate (17.5% digestible crude protein (DCP) v.s. 12.5% DCP) and concentrate allowances (standard v.s. substandard allowances after calving). Silage was offered ad libitum. Samples for estimation of serum immunoglobulin-G, white blood cells and lymphocyte responses to the mitogens phytohemagglutinin, concanavalin A and pokeweed mitogen were collected 4 weeks prior to expected calving, and 2, 4 and 8 weeks after calving. The levels of milk immunoglobulin-G were estimated at calving and 2, 4 and 8 weeks after calving. A significant positive relationship was found between the estimated energy balance and the lymphocyte response to mitogens. Little evidence was found for the existence of a significant relationship between the immunologic parameters and plasma indicators of metabolic status. The lymphocyte response to phytohemagglutinin and levels of serum immunoglobulin-G increased, while levels of milk immunoglobulin-G decreased during the period from calving to 8 weeks after calving. Increased milk somatic cell counts were associated with a significant decrease in the lymphocyte responses to mitogens. 相似文献
17.
为探讨葛根对奶牛脂肪肝细胞的作用机制,采用胶原酶二步灌流法分离病牛的肝细胞,并观察细胞形态。用不同浓度的葛根水提物处理肝细胞,生化法检测细胞上清液中丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)活性,并测定细胞裂解液中甘油三酯(TG)、胆固醇(TC)、丙二醛(MDA)、超氧化物歧化酶(SOD)的活性及含量。结果显示,50、100、500 μg/mL葛根水提物能极显著降低肝细胞中ALT、AST、TG、TC、MDA活性及含量,增加SOD活性(P < 0.01)。葛根水提物能显著改善肝细胞的相关生化指标,其机制可能与调节脂质代谢、抗脂质过氧化作用相关。 相似文献
18.
肝脏与胰腺发育的分子调控 总被引:1,自引:0,他引:1
肝脏和胰腺均由内胚层发育而来的消化器官,它们广泛地参与糖代谢、脂类代谢和蛋白质代谢.肝脏和胰腺的发育是一个动态连续的过程,并受到多种信号途径及转录因子的调控.基于上述特点和显著的医用价值,笔者对肝脏和胰腺发育过程中的分子作用机理作了系统地阐述,这将不仅有助于理解与肝脏和胰腺相关疾病的发病机理.同时也为有效地指导相关疾病的预防及治疗工作提供分子理论基础. 相似文献
19.
犬瘟热琼脂扩散试验方法的建立及初步应用 总被引:7,自引:0,他引:7
采用犬瘟热鸡胚成纤维细胞弱毒疫苗免疫绵羊制备琼脂扩散抗体,应用犬瘟热病貉肝脏(电镜检查“++”以上)制备琼脂扩散抗原,建立了琼脂扩散试验方法,用于犬瘟热病死动物肝、脾脏器中病毒抗原成分的检出。检测送检病料10份,与电镜检查结果比较,阳性符合率为85.7%(6/7),阴性符合率为75%(3/4),总体符合率为90%(9/10)。本方法特异、敏感,操作简便,易于推广应用。 相似文献
20.