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双酚A（BPA）是环境中内分泌干扰物（EDCs）之一,在食品包装、个人护理用品、收银机收据和医疗设备中随处可见,对机体产生负面影响。BPA作为一种弱外源性雌激素,能够结合经典的核雌激素受体ERα和ERβ并激活它们,这种激活会干扰正常的激素信号传导,影响卵巢功能和卵泡发育,从而导致月经周期不稳定和生殖问题。BPA还会干扰子宫内膜的正常发育和增殖,导致子宫内膜异位症、不孕症和胚胎着床等问题,对雌性生殖系统产生严重的毒性影响。到目前为止,BPA已经在水生环境、污水、自来水、土壤、灰尘和空气中被检测到,对人类和动物都构成了威胁。 相似文献
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1什么是环境激素环境激素是指由于人类的生产和生活而产生并释放到环境中,且在环境中持久存在的,通过直接或间接的方式在动物和人体内蓄积,能与激素受体结合起激素样作用、引起内分泌紊乱、使生殖机能失常的化学物质,也称为“环境荷尔蒙”。由于它是从外部环境进入人体,并产生类似人体激素的作用,所以学名称其为“外因性内分泌干扰物质”。环境激素的种类很多,包括二口恶英(dioxin)、二氯二苯氯乙烷(DDT)等农药及化学合成洗涤剂、防腐剂和多氯联苯(PCB)以及石棉、汞、镉及其化合物、苯乙烯、聚碳酸脂塑料等70多万种有害物质,其中人造化学… 相似文献
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α-甲基睾酮对稀有鮈鲫体内激素水平的影响 《畜牧与饲料科学》2016,37(6):1-1
环境内分泌干扰物（EDCs）对动物和人的健康有一定的危害作用,很大一部分环境内分泌干扰物最终都进入到了水环境中,对水生生物的生殖、内分泌等系统造成损伤。以稀有鮈鲫作为毒性试验材料,选择具有代表性的雄激素17α-甲基睾酮（MT）作为研究对象,采用酶联免疫法（ELISA）研究MT处理7 d对稀有鮈鲫体内雌二醇（E2）、睾酮（T）和11-酮基睾酮（11-KT）含量的影响。结果显示,经MT处理7 d后,雌鱼体内的E2、T和11-KT含量均极显著高于对照组（P〈0.01）,而雄鱼体内的E2、T和11-KT含量均极显著低于对照组（P〈0.01）。 相似文献
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植物雌激素对动物生殖及生殖内分泌的影响 总被引：5，自引：0，他引：5
植物雌激素是一类存在于豆科植物中的具有雌激素样和抗雌激素样作用的天然活性物质。大量的研究表明 ,植物雌激素具有抗肿瘤和降低心血管疾病、骨质疏松及痴呆症等发病率的作用。然而 ,有些报道认为动物采食富含植物雌激素的日粮可引起生殖功能的紊乱 ,导致繁殖性能降低。但近年来的研究表明 ,某些植物雌激素可作用于性腺轴 ,干扰体内的生殖内分泌功能 ,从而改善动物精液品质、性行为和提高产蛋率等生殖的机能。文章主要综述了植物雌激素对动物生殖及其内分泌的影响 ,为植物雌激素在畜禽业中的应用提供了科学的依据 相似文献
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The clinical differentiation of nervous and muscular locomotor disorders of sheep in Australia 总被引：2，自引：0，他引：2
CA BOURKE 《Australian veterinary journal》1995,72(6):228-234
SUMMARY Many of the nervous and muscular locomotor disorders that affect sheep throughout Australia are commonly referred to as ‘staggers’ syndromes. The range of clinical signs displayed by sheep suffering these disorders is sufficiently diverse to enable each syndrome to be graded into one of 5 progressive clinical groups. The first group, the limb paresis syndromes, includes the primary myopathies associated with the ingestion of Ixiolaena brevicompta, Malva parviflora, and Trachymene ochracea, as well as selenium and vitamin E disorders, Paroo virus staggers, congenital progressive muscular dystrophy, humpy back, hypocalcaemic muscle weakness, Tribulus terrestris staggers and tetanus . The second group is characterised by limb paresis with knuckling of the fetlocks, and includes the plant-associated toxicities of Romulea rosea, Stachys arvensis, Trachyandra divaricata, and Tribulus micrococcus, together with haloxon toxicity, enzootic ataxia (copper deficiency), and the probably genetic disorders of segmental axonopathy, neuroaxonal dystrophy, and degenerative thoracic myelopathy. Other locomotor disorders that fit more loosely into this group are listerial myelitis (post-dipping staggers), vitamin A deficiency, cervico-thoracic vertebral subluxation, Stypandra glauca toxicity, Ipomoea spp toxicity, ivermectin toxicity, and botulism . The third group, the falling syndromes, includes the probably genetic disorders of thalamic cerebellar neuropathy, cerebellar abiotrophy, and globoid cell leucodystrophy, together with Swainsona spp toxicity . The fourth group, the falling-with-tremors syndromes, includes the plant-associated toxicities of phalaris staggers, perennial rye grass staggers and nervous ergotism (Claviceps paspali) . The fifth group, the convulsive syndromes, includes the polioencephalomalacic entity nardoo fern (Marsilea drummondii) staggers, outbreaks of focal symmetrical encephalomalacia and the tunicaminyluracil toxicities known as annual ryegrass (Lolium rigidum) toxicity, annual beard grass (Polypogon monspeliensis) toxicity, blow away grass (Agrostis avenaceae) toxicity, and water damaged wheat (Triticum aestivum) toxicity . A dichotomous system is presented for the differential diagnosis of these groups of conditions . 相似文献
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Twenty-five known anthelmintic compounds were evaluated in vitro against the highly motile exsheathed non-feeding third-stage of Haemonchus contortus larvae. Activity was based on lack of motility or death of larvae after 24 h of chemical exposure. Six compounds (avermectins, closantel, levamisole, morantel, phenylhydrazone and ticarbodine) were active at a concentration of 100 μg cm?3 or less. The most active compounds were avermectins and levamisole. When higher in vitro concentrations were used, ten compounds (bephenium, coumaphos, dichlorovos, disophenol, hygromycin b, methyridine, parbendazole, phenothiazine, pyrantel and thiabendazole) exhibited activity. Nine compounds were found to be inactive; among these were the new benzimidazoles, i.e., albendazole, fenbendazole, mebendazole and oxibendazole. Because of the inactivity of the new benzimidazoles, this in vitro system is unsuitable as a routine screening tool. Also, the system appears to favor drugs that act quickly through percuticular entry. In an initial group of 5280 untested compounds, 254 (4.8%) exhibited in vitro activity at 100 μg cm?3 against the non-feeding larvae stage. The exogenous and in vitro cultivation techniques required for collecting, cleaning and exsheating the larvae are described. 相似文献
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Taxol and vinblastine have been widely used in cancer chemotherapy as anti-microtubule agents. However, there are on-going efforts to find new anti-microtubule agents with fewer of the side effects associated with these drugs, such as toxicity or the development of resistance. The standard method used to identify anti-microtubule agents has been the in vitro microtubule polymerization assay. One limitation of this system is that the only compounds selected are those that act on tubulin. Novel compounds whose targets are upstream or are related unknown molecules are not detected. Therefore, many researchers have recently tried to develop novel, phenotype-based drug screening systems. In this study, we developed an oocyte-based screening system for anti-microtubule agents. Dramatic phenotypic changes in microtubules can easily be observed in ovulated oocytes treated with microtubule-stabilizing or -destabilizing agents, such as taxol or vinblastine. After culturing with test samples for 5 h, oocytes were analyzed with fluorescence microscopy after immunostaining. In the oocyte-based screening system, the effective dose (ED50) of taxol for microtubule polymerization is approximately 5 nM, and the ED50 of vinblastine for microtubule depolymerization is approximately 2.5 nM. In addition, taxol-like and vinblastine-like compounds can be evaluated simultaneously in a single assay using this system. 相似文献
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Mohammad-Zadeh LF Moses L Gwaltney-Brant SM 《Journal of veterinary pharmacology and therapeutics》2008,31(3):187-199
5-Hydroxytryptamine, or serotonin, is a biogenic amine most noted for its role as a neurotransmitter. Manipulation of serotonin in animal models was used as a tool for studying its role in humans. Through such research serotonin has been shown to modulate gastrointestinal motility, peripheral vascular tone, cerebral vascular tone, and platelet function and has been implicated in the pathophysiology of mood disorders, emesis, migraine, irritable bowel syndrome (IBS), and pulmonary and systemic hypertension. The knowledge gained is being directly applied back to animals in research on drugs that manipulate the serotonergic system in dogs and cats. Increasing use and availability of drugs that manipulate the serotonergic system has created a circumstance through which a novel toxicity was discovered in both humans and animals. Serotonin Syndrome describes the clinical picture seen in humans and animals with serotonin toxicity. This paper provides a review the physiology of serotonin and its involvement in the pathophysiologic mechanisms of various conditions, including the Serotonin Syndrome. 相似文献
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镉胁迫下增施氮对白三叶草生长的影响和镉毒害的缓解效应研究 总被引：1，自引：0，他引：1
为了解镉(Cd)胁迫下施加外源氮对植物生长生理的影响及解毒机理, 本研究采用盆栽试验, 以白三叶草为材料, 研究了在重金属镉(CdCl2·2.5H2O)胁迫下施加氮[CO(NH2)2]对其生长、叶绿素含量、抗氧化酶活性、镉含量、谷胱甘肽(GSH)和植物络合素(PCs)含量的影响。结果表明, 单独的Cd处理显著抑制白三叶草生长及叶绿素的合成;而镉胁迫下施加氮显著促进了白三叶草的生长, 其生物量和叶绿素含量显著提高。同时, 镉胁迫下增施氮显著提高了植株过氧化物酶(POD)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性及白三叶草植株体内镉含量。单独镉处理显著增加了PCs含量, GSH含量显著降低;而镉胁迫下增施氮使GSH和PCs含量均显著增加。由此说明, 外源氮素在植物对重金属镉的解毒过程起到了重要的作用, 缓解了镉对白三叶草的毒害。 相似文献
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R H Poppenga 《Veterinary Clinics of North America: Equine Practice》2001,17(3):455-77, vi-vii
The use of dietary supplements (herbs, vitamins, minerals, amino acids, enzymes, and other compounds) is common in horses. They are heavily marketed in retail stores, magazines, and on the Internet. There is the perception that since these compounds are "natural" they are devoid of toxicity, and, therefore, they are safe to use. Some of the active compounds in supplements, however, have inherent toxicity, and using them may cause adverse effects. Even relatively non-toxic ingredients may be toxic if used over-zealously or for a long period of time. By and large, these compounds have not been tested for safety or efficacy when used as marketed, and, unfortunately, there is little regulatory oversight for such products. Other deleterious consequences of dietary supplement use include interaction of compounds in the products with conventional drugs, resulting in unexpected adverse effects, or the occurrence of violative residues in urine samples collected from show or performance horses. This article provides a brief overview of potential problems associated with dietary supplements, primarily focusing on products containing herbs and essential oils. 相似文献
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为探究外源抗坏血酸(AsA)对铜(Cu)胁迫下菊苣幼苗生长的缓解效应,本研究以普那菊苣为试验材料,采用溶液培养法研究外源AsA对50μmol·L-1Cu胁迫下菊苣幼苗的生长、Cu积累和生理特性的影响。结果表明,50μmol·L-1Cu胁迫严重抑制了菊苣幼苗的叶绿素含量、光合作用和生物量的积累,加剧了细胞膜脂质过氧化程度,降低了抗氧化酶(SOD、POD、CAT、APX)活性以及可溶性蛋白含量。外源AsA降低了根系对Cu的吸收和转运,缓解了Cu胁迫对菊苣幼苗的伤害,具体表现为根系、茎叶及总干物质量提高;减少了光合色素(叶绿素a、叶绿素b、总叶绿素以及类胡萝卜素)的降解,提高了光合作用参数;降低脂质过氧化对细胞膜的损伤;提高了抗氧化酶活性、可溶性蛋白含量以及内源AsA含量。总之,外源AsA通过提高Cu胁迫下菊苣幼苗光合作用特征、抗氧化酶活性和渗透调节物质的含量,缓解了Cu胁迫对菊苣幼苗生长的毒害作用。该结果为外源AsA应用于缓解植物Cu毒害及丰富菊苣耐Cu机制提供依据。 相似文献
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Udder inflammations, independently of significant losses in milk yield and alteration of its quality, can negatively affect cows' reproduction efficiency. Mastitis causes changes in many active constituents, both in milk and blood. Pathogenic changes in existing constituents and new active chemical compounds, generated during disease, can affect other organs, particularly the reproductive system and its mechanisms. Fertility disorders in mastitic cows are mostly connected with the activity of cytokines (especially TNF-alpha), cortisol, prostaglandin F2-alpha, reactive oxygen species (ROS), and classic inflammatory mediators. The successful treatment of mastitis as well as protection against udder infections should be considered important methods for prophylaxis of fertility disorders in cows. The first Polish trials indicated that injection of supportive drugs (antioxidants or lysozyme dimer or flunixin meglumine) to intramammarily treated cows can increase fertility in cows with mastitis. 相似文献
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Jung JW Park JS Hwang JW Kang KS Lee YS Song BS Lee GJ Yeo CD Kang JS Lee WS Jeon KS Um CH Kim YS Oh MJ Youn JP Li P Park JE Hwang SY 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1329-1333
The recent DNA microarray technology enables us to understand a large number of gene expression profiling. The technology has potential possibility to comprehend mechanism of multiple genes were related to compounds which have toxicity in biological system. So, the toxicogenomics through this technology may be very powerful for understanding the effect of unknown toxic mechanisms in biological system. We have studied that the effect of compounds related to hepatotoxin in vivo system using DNA microarray and classified chemicals which have been well characterized. We have studied three compounds; 2 peroxisome proliferators: Clofibrate (ethyl-p-chlorophenoxyisobutyrate), gemfibrozil (5-2[2,5-dimethyl-phenoxy]2-2-dimethyl-pentanonic), and an antiepileptic drug: phenytoin (5,5-diphenylhydantoin). Male Sprague-Dawely VAF(+) albino rats of 5-6 weeks old were treated with each compound for 24 hr and 2 weeks. 4.8 K cDNA microarray in house has been used for gene expression profiling. We found that the clustering of gene expression had similarity like as the toxic phenotype of compounds. 相似文献
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M. Brihoum H. Amory D. Desmecht D. Cassart S. Deleuze F. Rollin 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2010,24(5):1203-1210
Background: Reports of doxycycline‐induced toxicity are limited despite common use of this antibiotic to treat infectious respiratory disorders in calves. Objective: To describe previously unreported kidney lesions and diagnostic test results in doxycycline‐overdosed calves and to compare these results with other findings reported previously. Animals: Thirty‐two calves that presented with adverse effects after receiving high doses of doxycycline as a treatment for mild respiratory disorders. Method: Retrospective review of medical records. Results: Clinical examination identified mainly lethargy, dyspnea, cough, tongue paresia or paralysis associated with dysphagia and sialorrhea, tachycardia, tachypnea, and signs of myopathy. Blood analysis indicated increases in creatine kinase, lactate dehydrogenase, aspartate aminotransferase, and sorbitol dehydrogenase activities and increased serum creatinine and urea concentrations. ECG recordings and Doppler echocardiography examination identified ventricular premature beats and a decrease in left ventricular global and systolic function, respectively. Necropsy and histopathology disclosed necrosis of the myocardium, tongue, and some striated muscles, acute renal tubular necrosis, and fatty degeneration or congestion of the liver. Conclusions: Most of these findings corroborate previous observations made in doxycycline‐overdosed calves, and further suggest myocardial and striated muscular toxicity as well as renal toxicity in doxycycline‐overdosed calves. 相似文献