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排序方式: 共有593条查询结果,搜索用时 15 毫秒
591.
Porcine circovirus type 2 (PCV-2) coinfections in US field cases of postweaning multisystemic wasting syndrome (PMWS). 总被引:18,自引:0,他引:18
F J Pallarés P G Halbur T Opriessnig S D Sorden D Villar B H Janke M J Yaeger D J Larson K J Schwartz K J Yoon L J Hoffman 《Journal of veterinary diagnostic investigation》2002,14(6):515-519
The prevalence of different pathogens detected in combination with porcine circovirus type 2 (PCV-2) was studied retrospectively in field cases of postweaning multisystemic wasting syndrome (PMWS) diagnosed at the Iowa State University Veterinary Diagnostic Laboratory, Ames, Iowa, between January 2000, and September 2001. The presence of PCV-2 antigen in lymphoid tissues and/or lung, demonstrated by immunohistochemistry, together with moderate to severe lymphoid depletion and/or granulomatous lymphadenitis, was used as the criteria for the diagnosis of PMWS. A total of 484 cases fulfilled these criteria. Most of the cases (294/369) of PMWS occurred in pigs between the ages of 8 and 18 weeks, with a peak at 10 weeks of age. Porcine reproductive and respiratory syndrome virus was detected in 51.9% of the cases, Mycoplasma hyopneumoniae in 35.5%, bacterial septicemia in 14.0%, bacterial pneumonia in 7.6%, swine influenza virus in 5.4%, and PCV-2 alone in 1.9%. In cases with bacterial septicemia the most frequently isolated pathogen was Streptococcus suis. In cases with bacterial pneumonia, Pasteurella multocida was the most prevalent. 相似文献
592.
During the 2003–2004 epidemic in Korea, the infection time and within‐farm spread pattern of virus were analysed for the highly pathogenic avian influenza (HPAI) outbreak on chicken farms using regression models based on epidemiological data. Mortality observed on a given day had a positive linear association with time after initial infection. HPAI spread more rapidly on farms managed by employees and on farms with larger numbers of chicken houses in use. The disease spread more rapidly among layer chickens than among broilers. Using statistical model, we found that farmers recognize the abnormally high mortality resulting from HPAI approximately 5 days after infection. Without any intervention, entire flocks would die within 12 days of introduction of the HPAI virus to the infected farm. 相似文献
593.
Jinsheng Cui Eunji Kim Dong Hyun Moon Tae Ho Kim Ilnam Kang Yeonjung Lim Daniel Shin Sunghoon Hwang Young Eun Du Myoung Chong Song Munhyung Bae Jang-Cheon Cho Jichan Jang Sang Kook Lee Yeo Joon Yoon Dong-Chan Oh 《Marine drugs》2022,20(6)
Two new lipo-decapeptides, namely taeanamides A and B (1 and 2), were discovered from the Gram-positive bacterium Streptomyces sp. AMD43, which was isolated from a mudflat sample from Anmyeondo, Korea. The exact molecular masses of 1 and 2 were revealed by high-resolution mass spectrometry, and the planar structures of 1 and 2 were elucidated using NMR spectroscopy. The absolute configurations of 1 and 2 were determined using a combined analysis of 1H-1H coupling constants and ROESY correlations, the advanced Marfey’s method, and bioinformatics. The putative nonribosomal peptide synthetase pathway for the taeanamides was identified by analyzing the full genome sequence data of Streptomyces sp. AMD43. We also found that taeanamide A exhibited mild anti-tuberculosis bioactivity, whereas taeanamide B showed significant bioactivity against several cancer cell lines. 相似文献