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131.
Anna Capaldo Flaminia Gay Massimo Maddaloni Salvatore Valiante Maria De Falco Mauro Lenzi Vincenza Laforgia 《Water, air, and soil pollution》2012,223(5):2137-2143
The presence of illicit drugs and their metabolites in surface waters has to be considered a new type of hazard, still unknown, for the aquatic ecosystem, due to the potent pharmacological activities of all the illicit drugs. Our research was therefore aimed at evaluating the impact of illicit drugs on the aquatic fauna, till now still undervalued. To this aim, we verified the ability of the European eel (Anguilla anguilla), a well-known biomonitor of environmental contamination, to bioaccumulate cocaine, one of the most abundant illicit drugs found in surface waters. Silver eels were exposed to a nominal cocaine concentration of 20?ng/l for 1?month; at the same time, control, carrier, and post-exposure recovery groups were made. Brains, gills, liver, kidney, muscle, gonads, spleen, digestive tract, and sections of dorsal skin were assayed by high-pressure liquid chromatography. Cocaine was found in the tissues of the treated eels and, at low concentrations, in almost all tissues of post-exposure recovery eels. These results indicate that cocaine is able to accumulate into the eel tissues; its presence suggests potential risks for eels since cocaine could affect their physiology and contribute to their decline, and for humans consuming contaminated fish. 相似文献
132.
M. Craninx V. Fievez B. Vlaeminck B. De Baets 《Computers and Electronics in Agriculture》2008,60(2):226-238
The objectives of this study were: (1) to predict the rumen fermentation pattern from milk fatty acids using a machine learning technique, i.e. artificial neural networks (ANN) combined with feature selection and (2) to compare the prediction accuracy of the resulting model to that of a statistical multi-linear regression model, based on odd and branched chain milk fatty acids. Data were collected from 10 experiments with rumen fistulated dairy cows, resulting in a dataset of 138 observations. Feature selection was based on correlation and principal component analysis, and background physiological knowledge. Different ANN architectures and training algorithms were assessed. The evaluation of the model performance, based on the test dataset, showed a root mean square prediction error, expressed relative to the observed mean, of 2.65%, 7.67% and 7.61% of the observed mean for acetate, propionate and butyrate, respectively. Compared to a multi-linear regression model, the ANN revealed not to perform significantly better. However, the results confirm that milk fatty acids have great potential to predict molar proportions of individual volatile fatty acids in the rumen. 相似文献
133.
134.
脱落酸(ABA)信号通路在植物对干旱胁迫的响应中扮演着至关重要的角色;作为ABA受体,PYL家族蛋白在ABA信号转导中发挥核心作用。小麦TaPYL8是PYL家族的成员。为了明确TaPYL8是否参与小麦干旱胁迫响应,本研究分析了TaPYL8的表达模式,创建过表达TaPYL8拟南芥,并探讨了干旱对拟南芥生理生化及胁迫相关基因表达的影响。结果表明,TaPYL8表达量在干旱胁迫、外源ABA及PEG6000处理后上调。干旱胁迫下,过表达TaPYL8增强了拟南芥的存活率,降低了叶片失水率和MDA含量,提高了SOD、POD和CAT等抗氧化酶活性及AtSOD、AtP5CS1、AtABF3等胁迫相关基因的表达量。推测TaPYL8通过促进胁迫相关基因表达增强植物抗旱能力。 相似文献
135.
The cardiovascular changes induced by several sedatives were investigated in five ponies with a subcutaneously transposed carotid artery by means of cardiac output determinations (thermodilution technique), systemic and pulmonary artery pressure measurements (direct intravascular method) and arterial blood analysis (blood gases and packed cell volume). The cardiovascular depression (decrease in systemic blood pressure and cardiac output) was long lasting (greater than 90 min) after administration of propionylpromazine (0.08 mg/kg intravenous (i.v.)) together with promethazine (0.08 mg/kg i.v.). The phenothiazine-induced sedation was not optimal. alpha 2-Agonists (xylazine (0.60 mg/kg i.v.) and detomidine (20 micrograms/kg i.v.)) induced initial but transient cardiovascular effects with an increase in systemic blood pressure and a decrease in cardiac output for about 15 min. Second degree atrioventricular blocks and bradycardia were seen during this period. The cardiovascular depression was more pronounced during detomidine sedation. Atropine (0.01 mg/kg i.v.) induced a tachycardia with a decrease in stroke volume but did not alter the cardiac output or other cardiovascular parameters. It prevented the occurrence of the bradycardia and heart blocks normally induced by xylazine or detomidine. Atropine potentiated the initial hypertension induced by the alpha 2-agonistic sedatives (especially detomidine). The decrease in cardiac output induced by xylazine, and to a lesser extent by detomidine, was partially counteracted when atropine was given in advance. The atropine-xylazine combination seemed the best premedication protocol before general anaesthesia as it only resulted in minor and transient cardiovascular changes. 相似文献
136.
Cell cultures infected with BHV-1/F(syn), a recombinant bovine herpesvirus 1 (BHV-1) which expresses a synthetic open reading frame encoding the fusion (F) protein of the bovine respiratory syncytial virus (BRSV), showed a cytopathic effect (CPE) indistinguishable from that induced by wildtype BHV-1 although transient transfection experiments demonstrated that expression of the F protein leads to formation of large syncytia. Since it has been shown that glycoprotein M (gM) of pseudorabies virus inhibits BRSV F-induced syncytium formation in transient plasmid transfection experiments [Pseudorbies virus glycoprotein M inhibits membrane fusion. J. Virol. 74 (2000) 6760], the gM ORF of wtBHV-1 and BHV-1/F(syn) was interrupted. Infection of cell cultures with the resulting gM(-) mutant of BHV-1/F(syn) led to formation of syncytia, whereas the CPE in gM(-)BHV-1 infected cells was comparable to the CPE in wtBHV-1 infected cultures. Our results demonstrate that gM is not essential for BHV-1 replication in cell culture and that gM is involved in inhibition of the cell fusion activity of the BHV-1 expressed BRSV F protein. 相似文献
137.
138.
A. De Meyer S. Vandenabeele C. Ververs A. Martens K. Roels V. De Lange M. Hoogewijs C. De Schauwer J. Govaere 《Equine Veterinary Education》2017,29(1):7-9
An 11‐year‐old gelding presented with a large mass located in the dermis of his preputium that surrounded the penis completely. This mass was first noted years ago but did not increase in size. Histological examination diagnosed a fibroma. No treatment was initiated since no signs of discomfort were noticed and the gelding was performing at a high level in competitive showjumping. Next to skin tumours, tumours of the penis and preputium are most common. Most frequently, squamous cell carcinomas and sarcomas are diagnosed. Although fibromas can develop anywhere in connective tissue, a preputial location of a fibroma in a gelding is rare. Differential diagnosis and possible treatment options are discussed. 相似文献
139.
用从木瓜酶修饰的猪红细胞提取的 CD5 8分子 ,协同 ND 疫苗免疫 8日龄雏鸡 (分为试验 A组、对照 B组 ) ;用从正常猪红细胞提取的 CD5 8分子 ,协同 ND 疫苗免疫 18日龄雏鸡 (分为试验 C组、对照 D组 ) ,以β-微量法测定ND抗体效价 ,以 α-醋酸萘酯酶染色法检测鸡外周血 T细胞的变化 ,并分别用 NDV F4 8E9强毒株在免疫后 2 4 d攻击 A组和 B组鸡、39d攻击 C组和 D组鸡。结果表明 ,免疫前 ,8日龄雏鸡的 ND抗体效价为 2 5.8,18日龄雏鸡的 ND抗体均为阴性 ;免疫后 ,与对照 D组比较 ,试验 C组的 ND抗体提前 4 d达到 2 4 .8,并且试验 C组 ND抗体效价显著高于对照 D组 ( P<0 .0 1) ,保护期延长 ;试验 A组雏鸡体内 ND抗体变化和对照 B组相似 ,但试验 A组雏鸡外周血 T细胞数量显著高于对照 B组 ( P<0 .0 1或 P<0 .0 5 )。攻毒试验结果显示 ,试验 A组鸡死亡率为 33% ,对照 B组鸡死亡率为6 3% ;试验 C组鸡死亡率为 17% ,对照 D组鸡死亡率为 5 3%。本研究结果表明 ,猪红细胞 CD5 8分子具有较好的疫苗佐剂效应 相似文献
140.