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千里光的化学成分鉴定及体外抗菌试验 总被引：8，自引：0，他引：8
用分项试管预试法和圆形滤纸层析法对千里光的化学成分进行了检验;进行了千里光全草水煎剂及贡酮提取物的体外抗菌试验,结果表明,千里光全草含有黄酮及其甙类,酚性物质,鞣质,挥发油及生物碱等化学成分;千里光全草及其黄酮提取物对金黄色葡萄球菌,大肠埃希氏菌,肠炎沙门氏菌,炭疽杆菌,溶血性链球菌均有明显的抗菌作用。 相似文献
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用60％乙醇作溶剂制备千里先抗菌有效部位冻干粉（即千里光60％乙醇提取物）．分析其化学成分．并用改良寇氏法测定其对小鼠腹腔注射的急性半数致死量（LD50）。结果发现,千里光60％乙醇提取物合有生物碱、黄酮类化合物,但不含双稠吡咯啶生物碱;测得千里光60％乙醇提取物对小鼠腹腔注射的LD50为2206mg／kg,95％可信限为1867—2607mg／kg。表明千里光60％乙醇提取物属低毒性物质,并可保留千里光的有效成分生物碱和黄酮类化合物而排除其中的双稠吡略啶生物碱．进一步提高了千里光的安全性。 相似文献
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洋千里光(Senecio jacobaea)是世界上许多温暖湿润地区草地上生长的一种有毒杂草,含有6种双稠吡咯啶生物碱(PA),在肝内代谢为吡咯时,可引起肝脏形态和功能的不可逆变化。牛和马对 PA 中毒敏感,采食为体重5～10% 相似文献
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牦牛双稠吡咯啶生物碱中毒的确诊ＷｉｎｔｅｒＨｅｔａｌ首例牦牛双稠吡咯啶生物碱（ＰＡ）中毒的诊断在不丹王国进行，该中毒病在不丹一些地区相当严重。该病诊断最初是基于病理学检查，以后通过对甲醛固定的肝组织进行硫合吡咯代谢物的化学检验而被证实。在不丹考察期间... 相似文献
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含双稠吡咯啶生物碱（ＰＡｓ）的植物广泛分布于海拔８００～４０００ｍ的地区，种类繁多，尤以菊科千里光属、橐吾属和狗舌草属，豆科猪屎豆属及紫草科聚合草属和天芥菜属的多种植物中ＰＡｓ的含量大，危害严重；含ＰＡｓ的植物全草有毒，幼叶最甚，开花前，ＰＡｓ约占干物质的１．２％，开花后，约占０．４％～０．５％。已知有３０余种ＰＡｓ具有毒性，主要损害肝脏，有些还兼具肺毒性。本文综述了动物ＰＡｓ中毒的病因、病理变化、ＰＡｓ的结构和中毒机制等方面的最新研究进展。探讨了ＰＡｓ中毒病研究现存问题和解决途径 相似文献
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本试验采用植物化学成分系统预试法、生物碱系统提取法和薄层色谱技术对冰川棘豆地上部分全草的化学成分,特别是生物碱成分进行了薄层色谱分析。结果表明冰川棘豆含有生物碱、氨基酸和蛋白质、有机酸、酚类和鞣质、多糖及甙类、皂甙、甾体、香豆素、萜类以及蒽醌类。不含挥发油、黄酮体、氰甙和脂肪族硝基化合物;5 000 g冰川棘豆干草粉经醇类溶剂提取得总浸膏312.0 g,再经酸化、碱化处理,收集碱水液依次用氯仿、乙酸乙酯和正丁醇分段萃取,分别得氯仿部分0.5 g,乙酸乙酯部分5.4 g,正丁醇部分52.0 g,初步表明冰川棘豆生物碱主要集中在正丁醇提取部分,以强极性生物碱为主;各部分生物碱提取物经薄层层析分析,结果表明氯仿部分至少有9种生物碱,乙酸乙酯部分至少有11种,正丁醇部分至少有4种。经与苦马豆素标准样品对照,证明三部分提取物均含有苦马豆素。 相似文献
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<正>大花千里光(Senecio ambraceus Turcz.ex DC.)为菊科千里光族千里光属植物,其茎、叶、花、果中蛋白质含量高,我国北部分布广泛,可作为家畜饲料[1]。千里光属植物一般含有吡咯里西啶生物碱,虽有一定的肝毒性和致突变性,导致临床应用谨慎,但因其具有抗癌活性已被作为抗癌药物前体物质开展了人工合成类似物的研究工作。目前关于大花千里光的研究少见报道,报道较多的是千里光属植物的化学成 相似文献
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通常情况下,双稠吡咯啶生物碱能引起以动物肝功能衰竭为特征的慢性中毒性疾病。该病可以由多种有毒植物引起,其中狗舌草、千里光属植物、洛苛草以及黄黑草籽是引起该病的最常见的植物。动物的易感性存在个体差异,生长期的动物最易感,牛、马、鹿和猪是易感动物,绵羊和山羊的中毒剂量大约比牛高20倍。结合家畜的采食、临床症状和实验室诊断可作出诊断。现介绍该病的治疗和控制方法。 相似文献
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Pharmacokinetic properties of enrofloxacin in rabbits. 总被引：4，自引：0，他引：4
R L Broome D L Brooks J G Babish D D Copeland G M Conzelman 《American journal of veterinary research》1991,52(11):1835-1841
The pharmacokinetic properties of the fluoroquinolone antimicrobial enrofloxacin were studied in New Zealand White rabbits. Four rabbits were each given enrofloxacin as a single 5 mg/kg of body weight dosage by IV, SC, and oral routes over 4 weeks. Serum antimicrobial concentrations were determined for 24 hours after dosing. Compartmental modeling of the IV administration indicated that a 2-compartment open model best described the disposition of enrofloxacin in rabbits. Serum enrofloxacin concentrations after SC and oral dosing were best described by a 1- and 2-compartment model, respectively. Overall elimination half-lives for IV, SC, and oral routes of administration were 2.5, 1.71, and 2.41 hours, respectively. The half-life of absorption for oral dosing was 26 times the half-life of absorption after SC dosing (7.73 hours vs 0.3 hour). The observed time to maximal serum concentration was 0.9 hour after SC dosing and 2.3 hours after oral administration. The observed serum concentrations at these times were 2.07 and 0.452 micrograms/ml, respectively. Mean residence times were 1.55 hours for IV injections, 1.46 hours for SC dosing, and 8.46 hours for oral administration. Enrofloxacin was widely distributed in the rabbit as suggested by the volume of distribution value of 2.12 L/kg calculated from the IV study. The volume of distribution at steady-state was estimated at 0.93 L/kg. Compared with IV administration, bioavailability was 77% after SC dosing and 61% for gastrointestinal absorption. Estimates of predicted average steady-state serum concentrations were 0.359, 0.254, and 0.226 micrograms/ml for IV, SC, and oral administration, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Supplementation of the diets of rats with branched chain amino acids (BCAA: leucine, isoleucine, valine) did not alter their susceptibility to chronic poisoning by tansy ragwort (Senecio jacobaea), which contains hepatotoxic pyrrolizidine alkaloids (PA). Phenobarbital in the diet, which alters liver microsomal enzyme activity, also did not alter susceptibility to PA poisoning. A combination of butylated hydroxyanisole (BHA), cysteine and BCAA did increase (P less than .05) survival time of rats fed tansy ragwort. Dietary BHA and cysteine increased the survival time of rats injected with the PA monocrotaline, with evidence that addition of vitamin B12 and folic acid improved the effectiveness of this treatment. In a chronic feeding trial with tansy ragwort, a combination of BHA and cysteine increased (P less than .05) the survival times of rats, showing protective activity against PA poisoning. A mixture of B-complex vitamins, or vitamin B12-folic acid, was not effective in improving the response. 相似文献
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J. O. Atteh O. M. Onagbesan K. Tona E. Decuypere J. M. C. Geuns J. Buyse 《Journal of animal physiology and animal nutrition》2008,92(6):640-649
A perennial schrub, stevia, and its extracts are used as a natural sweetener and have been shown to possess antimicrobial properties. Stevia contains high levels of sweetening glycosides including stevioside which is thought to possess antimicrobial and antifungal properties. Little is known about the nutritional value of the schrub in livestock. This study determined the potential use of the shrub as a prebiotic animal feed supplement in light of the recent ban on the use of antibiotics in animal feed and the role of its constituent stevioside in the effects of the shrub. Male Cobb broiler chicks were fed a basal broiler diet without antibiotic but with performance enhancing enzyme mix (positive control), a basal diet without antibiotic and enzymes (negative control), or diets in which 2% of the negative control diet was replaced with either dried ground stevia leaves or 130 ppm pure stevioside during 2 week starter and 2 week grower periods. Body weight gains, feed conversion, abdominal fat deposition, plasma hormone and metabolites and caecal short chain fatty acids (SCFA) were measured in the broilers at 2 and 4 weeks of age. There was no significant effect of the treatments on feed intake during the starter period but birds fed diet supplemented with stevia leaves and stevioside consumed more feed (p < 0.05) than those fed the positive control diet during the grower period. Weight gain by birds fed the positive control and stevioside diets was higher (p < 0.05) than those fed other diets only during the starter period. Feed/gain ratio of birds fed the positive control and stevioside diets was superior (p < 0.05) to others. There was no effect of the treatments on nutrient retention and water content of the excreta. Dietary stevia leave and stevioside decreased total concentration of SCFA and changed their profile in the ceca. There was no effect of the treatments on pancreas weight. Dietary stevia reduced blood levels of glucose, triglycerides and triiodothyronine (T3) but had no effect on non-esterified fatty acids. In contrast, stevioside only decreased T3. Both the stevia leaves and stevioside diets significantly increased abdominal fat content. It is concluded that dietary enzyme growth promoters are beneficial to the broilers only during the starter stage and that inclusion of stevia leaves or stevioside has no beneficial effect on the performance of broilers. 相似文献
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为了优化苦参碱的提取工艺,以浸膏收率、苦参碱含量为评价指标,选择用水量、提取时间及提取次数为考察因素,利用L9（3^4）正交试验法优选出水煎煮法提取苦参碱的最佳工艺条件为用8倍量水提取3次,每次提取2h。采用乙醇沉淀及三氯甲烷萃取相结合的方法对苦参粗提物进行纯化,浓缩药液浓度为1．0g生药／mL时进行醇沉,醇沉后调节药液的pH值至9～11用三氯甲烷萃取3次。优选出的提取工艺稳定、可行,可用于苦参碱的工业化提取。 相似文献