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31.
Serum samples from 1,011 wild boars hunted in 2012 were collected for serological surveillance for 4 subtypes (pandemic A (H1N1) 2009 and classical H1N1, H1N2 and H3N2) of swine influenza virus (SIV). Samples from 12 of the boars were identified as positive for SIV (pandemic A (H1N1) 2009, n=9; classical H1N1, n=2; and H1N2, n=1) by a hemagglutination inhibition test (HI test) and a nucleoprotein (NP)-based enzyme-linked immunosorbent assay (NP-ELISA). Although the overall seroprevalence of SIV in the Korean wild boar population was somewhat low compared with that in China and the U.S.A., the apparent prevalence of pandemic H1N1 was notable. Therefore, continuous monitoring of the wild boar population is needed as it may be a major reservoir for pandemic H1N1, facilitating its spread to humans and domestic pigs.  相似文献   
32.
Classical swine fever (CSF) is a highly contagious systemic hemorrhagic viral disease of pigs. Wild boar plays a crucial role in the epidemiology of CSF. Between 2010 and 2014, samples were collected nationwide from 6,654 wild boars hunted in South Korea. Anti-CSF antibodies were identified in 0.59% (39 of 6,654) of the wild boar samples using a virus neutralization test and were primarily detected in wild boars living close to the demilitarized zone and the area of the Taebaek Mountains surroundings. The CSF virus (subgroup 2.1b) was isolated from two wild boars captured in a nearby border area. The criteria used to define high-risk areas for targeted CSF surveillance in South Korea should be further expanded to include other regions nationwide.  相似文献   
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34.
A survey by mail in 1979 of 995 sheep farmers in Victoria enquiring as to the occurrence of hairy shaker disease (HSD) in lambs on their farms resulted in a 48% response. A total of 17 farms reported the presence of HSD. One hundred and eleven ewes produced lambs with HSD representing a small proportion only of the ewes (0.8%) on these farms and an even smaller percentage of the total ewes (0.03%) in the survey. Abortions were not prevalent on the majority of farms reporting HSD. There was no evidence that HSD was more common in any particular area in Victoria. As was anticipated mucosal disease virus/bovine virus diarrhoea (MDV) antibody was often present in serums from affected sheep. It was concluded that at present, the hairy shaker form of border disease did not appear to be an economically important problem in Victoria.  相似文献   
35.
目前大多数研究主要是针对体外的卵母细胞凋亡,并且通常采用抗癌试剂来人为的引入。然而,对体内卵母细胞死亡的过程还不是很明确。为了查明体内未受精卵的死亡过程,我们检测了从输卵管壶腹部冲出的注射了HCG后不同间隔的卵母细胞中的细胞化学物质的改变情况。在每一个收集的时间段,在显微镜下将收集的卵母细胞从表观上分成四组:单细胞卵母细胞(没有激活和没有核或胞浆移动),激活的卵母细胞(带有核的单细胞,2-或4-细胞),碎裂的卵母细胞及其死亡的卵母细胞。随着时间的推移,单细胞卵母细胞的数量下降,死亡的卵母细胞数量增加,但是激活或碎裂的卵母细胞数量未发生改变。同时,检测到的大多数死亡的卵母细胞都是单细胞。在每一个时间点上,用抗微管蛋白抗体对单细胞卵母细胞进行着色,来检测它们的纺锤体状态。在注射HCG24h之后,大多数超排后的卵母细胞都有两极纺锤体,然而在超排后64h的单细胞卵母细胞就没有纺锤体。结果表明,大多数的体内卵母细胞在单细胞期就出现死亡,而激活或碎裂的卵母细胞则不是。  相似文献   
36.
Research on mammals in the Guianas of northern South America has had a checkered history. In this review, I summarize the notable contributions to mammalogical study in Guyana, Suriname and French Guiana. These studies began in the mid‐18th century with the binomial nomenclature system of scientific classification created by the Swedish naturalist Carl Linnaeus, who described 23 species new to science based on holotype specimens from the Guianas. Notwithstanding popular accounts by amateur naturalists visiting this region, over the next 7 decades there was only sporadic taxonomic work done on Guianan mammals primarily by researchers at European museums. The first comprehensive biological exploration took place in the 1840s during a geographic survey of the boundaries of British Guiana. However, it was not until almost half a century later that scientific publications began to regularly document the increasing species diversity in the region, including the prodigious work of Oldfield Thomas at the British Museum of Natural History in London. Another lull in the study of mammals occurred in the mid‐1910s to the early 1960s after which foreign researchers began to rediscover the Guianas and their pristine habitats. This biological renaissance is still ongoing and I give a prospectus on the direction of future research in one of the last frontiers of tropical rainforest. An initiative that would be greatly beneficial is the establishment of a university network in the Guianas with graduate‐based research to develop a cadre of professional experts on biodiversity and evolution as seen in other countries of South America.  相似文献   
37.
Two new bicyclogermacrenes, capgermacrenes A (1) and B (2), were isolated with two known compounds, palustrol (3) and litseagermacrane (4), from a population of Bornean soft coral Capnella sp. The structures of these metabolites were elucidated based on spectroscopic data. Compound 1 was found to inhibit the accumulation of the LPS-induced pro-inflammatory IL-1β and NO production by down-regulating the expression of iNOS protein in RAW 264.7 macrophages.  相似文献   
38.
Rat bocavirus (RBoV) and rodent bocavirus (RoBoV) have previously been detected in Rattus norvegicus; however, these viruses have not been reported in rodent populations in Malaysia. We investigated the presence of RBoV and RoBoV in archived rodent specimens. DNA barcoding of the rodent cytochrome c oxidase gene identified five different species: Rattus tanezumi R3 mitotype, Rattus tiomanicus, Rattus exulans, Rattus argentiventer, and Rattus tanezumi sensu stricto. Three spleens were positive for RBoV (1.84%; 3/163), but no RoBoV was detected. Phylogenetic analyzes of the partial non-structural protein 1 gene grouped Malaysian RBoV strains with RBoV strains from China. Further studies among rats from different geographical locations are warranted for this relatively new virus.  相似文献   
39.
In this study, we investigated the anti-allergic effects of 3,4-dihydroxybenzaldehyde (DHB) isolated from the marine red alga, Polysiphonia morrowii, in mouse bone-marrow-derived cultured mast cells (BMCMCs) and passive cutaneous anaphylaxis (PCA) in anti-dinitrophenyl (DNP) immunoglobulin E (IgE)-sensitized mice. DHB inhibited IgE/bovine serum albumin (BSA)-induced BMCMCs degranulation by reducing the release of β-hexosaminidase without inducing cytotoxicity. Further, DHB dose-dependently decreased the IgE binding and high-affinity IgE receptor (FcεRI) expression and FcεRI-IgE binding on the surface of BMCMCs. Moreover, DHB suppressed the secretion and/or the expression of the allergic cytokines, interleukin (IL)-4, IL-5, IL-6, IL-13, and tumor necrosis factor (TNF)-α, and the chemokine, thymus activation-regulated chemokine (TARC), by regulating the phosphorylation of IκBα and the translocation of cytoplasmic NF-κB into the nucleus. Furthermore, DHB attenuated the passive cutaneous anaphylactic (PCA) reaction reducing the exuded Evans blue amount in the mouse ear stimulated by IgE/BSA. These results suggest that DHB is a potential therapeutic candidate for the prevention and treatment of type I allergic disorders.  相似文献   
40.
A study was performed to evaluate the histologic changes among fingerling channel catfish, Ictalurus punctatus Rafinesque, fed purified diets containing gossypol from gossypol–acetic acid. The catfish were maintained on diets with 0, 300, 600, 900, 1200 or 1500 mg gossypol kg?1 diet for 12 weeks, and histologic samples from the stomach, proximal and distal intestines, pancreas, liver, and spleen were obtained from fish in all groups. Stomach sections exhibited significant gastric gland necrosis in fish fed 600 mg gossypol kg?1 diet or higher. Non‐existent‐to‐mild enterocyte vacuolization loss, inflammatory cell infiltration, and hyperplastic lamina propria were noted in the intestinal sections from gossypol‐fed fish, but no significant differences in severity scores were noted. The pancreas from fish fed doses of gossypol above 600 mg gossypol kg?1 diet exhibited significant mild‐to‐severe necrosis, and livers from fish fed 900 and 1500 mg gossypol kg?1 diet exhibited significantly higher pigment deposition. No other significant histologic differences were observed in the fish fed diets containing gossypol–acetic acid. The data in this study indicates that at least 600–900 mg gossypol kg?1 purified diet can cause statistically significant histologic changes in fingerling channel catfish, suggesting that gossypol should remain at concentrations below 600 mg gossypol kg?1 diet.  相似文献   
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