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141.
Rice CC Kruger JM Venta PJ Vilnis A Maas KA Dulin JA Maes RK 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(3):293-302
Feline caliciviruses (FCVs) are potential etiologic agents in feline idiopathic lower urinary tract disease (I-LUTD). By means of a modified virus isolation method, we examined urine obtained from 28 male and female cats with nonobstructive I-LUTD, 12 male cats with obstructive I-LUTD, and 18 clinically healthy male and female cats. All cats had been routinely vaccinated for FCV. Two FCVs were isolated; I (FCV-U1) from a female cat with nonobstructive I-LUTD, and another (FCV-U2) from a male cat with obstructive I-LUTD. To determine the genetic relationship of FCV-U1 and FCV-U2 to other FCVs. capsid protein gene RNA was reverse transcribed into cDNA, amplified, and sequenced. Multiple amino acid sequence alignments and phylogenetic trees were constructed for the entire capsid protein, hypervariable region E, and the more conserved (nonhypervariable) regions A, B, D, and F. When compared to 23 other FCV isolates with known biotypes, the overall amino acid sequence identity of the capsid protein of FCV-U1 and FCV-U2 ranged from 83 to 96%; identity of hypervariable regions C and E ranged from 58 to 85%. Phylogenetically, FCV-U1 clearly separated from other FCV strains in phenograms based on nonhypervariable regions. In contrast, FCV-U2 consistently segregated with the Urbana strain in all phenograms. Clustering of isolates by geographic origin was most apparent in phenograms based on nonhypervariable regions. No clustering of isolates by biotype was apparent in any phenograms. Our results indicate that FCV-UI and FCV-U2 are genetically distinct from other known vaccine and field strains of FCV. 相似文献
142.
V. M. Dato E. R. Campagnolo D. U. Shah M. J. Bellush C. E. Rupprecht 《Zoonoses and public health》2015,62(3):222-227
Adverse events can occur after rabies post‐exposure prophylaxis (PEP), and linkage to causality is often difficult to determine. We report a case of recurrent temporary paralysis that began immediately after the initiation of rabies PEP in a man exposed to a bat. The recurrent temporary paralysis first occurred in the patient after his initial dose and then again after day 3 of his rabies PEP. The PEP was terminated prior to a serologic response. The patient continued to experience numerous discrete episodes of temporary paralysis for over two years. 相似文献
143.
玉米轮选系产量配合力和抗病性研究 总被引:1,自引:0,他引:1
研究了东农群体—1的第一轮选出的自交系和组成该群体的较好原始亲本的产量配合力和抗大斑病能力.结果表明,轮选系的一般配合力效应和抗大斑病能力均优于较好原始亲本,且差异达到0.05的显著水平.也证明了用轮回选择法提高玉米自交系的配合力和抗病能力很有效。 相似文献
144.
The objective of this study was to examine laryngeal function at rest and during ridden exercise and to further analyse the impact of different head and neck positions on the laryngeal function in ridden sport horses. Fifty‐eight Warmblood horses were examined endoscopically during ridden exercise as well as during quiet breathing at rest before and after sedation. Four different head‐neck positions (unrestrained, reference, elevation and hyperflexion) were assessed during the exercise test. Laryngeal function was graded at rest and for every combination of gait and head and neck position during exercise. There was a significant correlation between the grade of laryngeal function during exercise and at rest both before (correlation coefficient = 0.794) and after (correlation coefficient = 0.741) sedation (P<0.01). No significant association was found between the grade of laryngeal function during exercise and the different head and neck positions. 相似文献
145.
146.
目前神经网络研究文献成果较多,虽然在水质精准预测方面起到了一定的参考,但由于文献缺少科学分类,使用率不高,导致学者难以找到研究切入点。针对这一问题,本文将神经网络方法在养殖区水质精准预测方面的文献按照海水和淡水两大领域进行分类,主要对每个领域所应用的预测模型从正反馈架构、循环架构和混合架构三个方向对海水时空序列文献进行分类研究和综述,发现混合架构模型的预测性能优于正反馈模型和循环架构模型,有利于提升不同深度水质预测模型的精度。另外,本文对基于神经网络方法的三维水质预测模型进行了初步探讨,发现学者的研究成果更多地集中在水表层和水中层的不同位置水质参数的变化方面,而神经网络方法对水表层水质预测精度比水中层和水深层水质预测精度高。 相似文献
147.
以中药材天地网30种中药材价格指数为研究对象,使用HP-LSTM-MLP混合预测模型对中药材单品种价格指数和综合价格指数进行预测,并与LSTM(long short term memory networks,长短期记忆网络)、RNN(recurrent neural network,循环神经网络)、GRU(gated recurrent unit,门控循环单元)等预测模型进行比较分析。研究结果表明,在RMSE和R_(score)~2两个预测效果衡量指标中,HP-LSTM-MLP混合预测模型的RMSE为65.33,R_(score)~2为0.99,皆优于其他3种模型。采用HP-LSTM-MLP模型分别预测我国30种主要中药材综合价格指数以及单品种价格指数,结果显示,对中药材综合价格指数的预测结果平均相对误差为1.89%;对黄连、连翘和麦冬等单品种价格指数的预测结果的平均相对误差分别为3.36%、5.66%和3.22%,说明HP-LSTM-MLP模型泛化能力较好,对我国中药材价格指数预测具有一定的应用价值。 相似文献
148.
149.
OBJECTIVE: Evaluation of the LMA-ProSeal for positive pressure ventilation (PPV) in the pig. STUDY DESIGN: Prospective observational study. ANIMALS: Twelve German country pigs, weighing 25-62 kg. METHOD: Lungs of pigs were mechanically ventilated under general anaesthesia using the LMA-ProSeal. The ease of insertion, number of attempts and total time until placement of the LMA-ProSeal and gastric tube were recorded. Bronchoscopy was performed to determine the position of the LMA-ProSeal and to detect signs of aspiration. Ventilation variables and the leak airway pressure (P(leak)) were measured. An arterial blood gas sample was taken to determine the adequacy of ventilation. RESULTS: The airway was secured in all pigs within 39 +/- 19 seconds (27-51). Different sizes of LMA-ProSeal were used; up to 30 kg: size 3, up to 43 kg: size 4; and above 43 kg: size 5. In all but one animal the P-LMA and gastric tube were inserted at the first attempt. In nine animals gastric fluid was drained through the gastric tube. There was no evidence of aspiration in any animal. The mean [+/-SD (95%CI)]P(leak) was 28.8 +/- 7.5 cm H(2)O (24.06-33.60) and normal ventilation was achieved in all animals. CONCLUSIONS: The results of this study indicate that the airway of pigs weighing 25-62 kg can be secured safely and reliably with the sizes 3, 4 and 5 LMA-ProSeal. CLINICAL RELEVANCE: Endotracheal intubation in pigs can be difficult so there is a risk of hypoxemia in the apnoeic animal. With the LMA-ProSeal the airway can be secured rapidly, safely and reliably. Use of the Standard-LMA under PPV can be associated with gas leakage into the stomach and the subsequent risk of gastric distension and regurgitation. Both the ability to drain the stomach and the high P(leak) of the LMA-ProSeal could contribute to improved protection against aspiration under PPV. 相似文献
150.