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排序方式: 共有1582条查询结果,搜索用时 156 毫秒
971.
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Ramirez A Wang C Prickett JR Pogranichniy R Yoon KJ Main R Johnson JK Rademacher C Hoogland M Hoffmann P Kurtz A Kurtz E Zimmerman J 《Preventive veterinary medicine》2012,104(3-4):292-300
Currently virus surveillance in swine herds is constrained by the cost-effectiveness and efficiency of sampling methods. The objective of this study was to assess the value of using oral fluids collected by barn personnel as a method of surveillance based on PCR testing. Approximately 12,150 pigs in 10 wean-to-finish barns on 10 farms were monitored for the presence of porcine circovirus type 2 (PCV2), porcine reproductive and respiratory syndrome virus (PRRSV), influenza A virus (IAV), and Torque teno virus genogroups 1 (TTV1) and 2 (TTV2) by sampling oral fluid specimens. Oral fluid samples were collected from 6 pens at each site starting at the time of pig placement (~3 weeks of age) and continuing thereafter at 2-week intervals for a period of 18 weeks. Data were analyzed both on a pen basis and barn basis. Overall, 508 (85%) samples were positive for PCV2, 73 (12%) for PRRSV, 46 (8%) for IAV, 483 (81%) for TTV2, and 155 (26%) for TTV1 during the study period. The estimated arithmetic means of the quantitative PCR-positive oral fluids for PCV2, PRRSV, and IAV were 1×10(4.62), 1×10(4.97), and 1×10(5.49)per ml. With a single exception, all barns were positive for PCV2 and TTV2 at every sampling point in the study. Virus detection varied among barns, particularly for IAV and PRRSV. The pen level, cumulative distribution of agent combinations between all 10 barns were statistically different. The most commonly observed patterns were PCV2+TTV2 (239 pen samples, 40%), PCV2+TTV1+TTV2 (88 pen samples, 15%), and PCV2 alone (66 pen samples, 11%). This "proof-of-concept" project showed that a variety of viruses could be detected either intermittently or continuously in pig populations and demonstrated that barn herd virus status is highly variable, even among barns in the same production system. Oral fluid sampling is a promising approach for increasing the efficiency and cost effectiveness of virus surveillance in swine herds. 相似文献
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Huang X McCoy AB Bowman JM Johnson LM Savage C Dong F Nesbitt DJ 《Science (New York, N.Y.)》2006,311(5757):60-63
We present two quantum calculations of the infrared spectrum of protonated methane (CH5+) using full-dimensional, ab initio-based potential energy and dipole moment surfaces. The calculated spectra compare well with a low-resolution experimental spectrum except below 1000 cm(-1), where the experimental spectrum shows no absorption. The present calculations find substantial absorption features below 1000 cm(-1), in qualitative agreement with earlier classical calculations of the spectrum. The major spectral bands are analyzed in terms of the molecular motions. Of particular interest is an intense feature at 200 cm(-1), which is due to an isomerization mode that connects two equivalent minima. Very recent high-resolution jet-cooled spectra in the CH stretch region (2825 to 3050 cm(-1)) are also reported, and assignments of the band origins are made, based on the present quantum calculations. 相似文献
975.
Kurosawa TA Ruth JD Steurer J Austin B Heng HG 《Veterinary radiology & ultrasound》2012,53(3):329-332
A 13-year-old neutered female Labrador retriever had inspiratory dyspnea secondary to bilateral laryngeal paralysis. Radiographically, there was pectus excavatum with a mediastinal shift to the right. Arytenoid lateralization was performed, relieving the upper respiratory obstruction, and the sternal deformity also resolved. Chronic upper respiratory obstruction should be considered in dogs with pectus excavatum. Furthermore, correction of upper respiratory obstruction has the potential to result in resolution of pectus excavatum. 相似文献
976.
Kummeling A Penning LC Rothuizen J Brinkhof B Weber MF van Sluijs FJ 《Veterinary journal (London, England : 1997)》2012,191(3):383-388
In dogs with a congenital portosystemic shunt (CPSS), the outcome after CPSS attenuation is difficult to predict but is most likely related to hepatic and vascular proliferation that follows the attenuation. The aim of this study was to evaluate the prognostic value of shunt localization (extrahepatic vs. intrahepatic), plasma albumin concentration and hepatic mRNA expression of 19 genes involved in hepatic and vascular growth. The study population consisted of 48 dogs that were referred for surgical ligation of a single intrahepatic or extrahepatic CPSS. Gene expression was measured in intraoperatively sampled hepatic tissue with quantitative real-time PCR. Albumin, methionine adenosyltransferase 2α (MAT2α) and HGF activator (HGFac) were positively associated with complete recovery after CPSS attenuation using multivariate statistical analyses. Individual outcome could be correctly predicted in 83% of dogs using albumin, MAT2α and HGFac as high or low values compared to cut-off values of 19.5 g/L, 0.457 and 0.974, respectively. These variables predicted outcome after CPSS ligation better than shunt localization or albumin alone. Other evaluated gene products were not correlated with outcome. 相似文献
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