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Mongolia combines a near absence of domestic poultry, with an abundance of migratory waterbirds, to create an ideal location to study the epidemiology of highly pathogenic avian influenza virus (HPAIV) in a purely wild bird system. Here we present the findings of active and passive surveillance for HPAIV subtype H5N1 in Mongolia from 2005–2011, together with the results of five outbreak investigations. In total eight HPAIV outbreaks were confirmed in Mongolia during this period. Of these, one was detected during active surveillance employed by this project, three by active surveillance performed by Mongolian government agencies, and four through passive surveillance. A further three outbreaks were recorded in the neighbouring Tyva Republic of Russia on a lake that bisects the international border. No HPAIV was isolated (cultured) from 7,855 environmental fecal samples (primarily from ducks), or from 2,765 live, clinically healthy birds captured during active surveillance (primarily shelducks, geese and swans), while four HPAIVs were isolated from 141 clinically ill or dead birds located through active surveillance. Two low pathogenic avian influenza viruses (LPAIV) were cultured from ill or dead birds during active surveillance, while environmental feces and live healthy birds yielded 56 and 1 LPAIV respectively. All Mongolian outbreaks occurred in 2005 and 2006 (clade 2.2), or 2009 and 2010 (clade 2.3.2.1); all years in which spring HPAIV outbreaks were reported in Tibet and/or Qinghai provinces in China. The occurrence of outbreaks in areas deficient in domestic poultry is strong evidence that wild birds can carry HPAIV over at least moderate distances. However, failure to detect further outbreaks of clade 2.2 after June 2006, and clade 2.3.2.1 after June 2010 suggests that wild birds migrating to and from Mongolia may not be competent as indefinite reservoirs of HPAIV, or that HPAIV did not reach susceptible populations during our study.  相似文献   
2.
Despite concern over the conservation status of many Mongolian salmonids and the importance of their ecological role in Mongolia's aquatic ecosystems, little is known about their basic biology. Hovsgol grayling (Thymallus nigrescens) is endemic to Lake Hovsgol, Mongolia and listed as endangered on the Mongolian Red List. Baikal grayling (T. baicalensis) and lenok (Brachymystax lenok) are found in lakes and rivers throughout the Selenge drainage. A detailed study of the age and growth of these three salmonids was conducted based on 1,682 samples collected from July 2006 to July 2013 in Lake Hovsgol, its outlet the Eg River, and one of the Eg's largest tributaries, the Uur River. Our results suggest that Hovsgol grayling in particular can reach a much older maximum age (17 years in our samples) than previously believed based on aging from scales. Female Hovsgol grayling were heavier at a given length than their male counterparts. Lenok had a greater average length‐at‐age in Lake Hovsgol compared to the rivers and greater weight‐at‐length in the warmer Uur River than in the Eg; female lenok from the rivers had a greater average length‐at‐age than their male counterparts. This study provides critical new information for the management and conservation of these threatened salmonid species in Mongolia.  相似文献   
3.
Several naturally occurring peptides in bovine milk were characterized by tandem mass spectrometry and Edman degradation. Chromatograms of peptide fractions (passed through an ultra‐filtration membrane, nominal molecular weight limit 3000) prepared from colostrum (collected immediately after parturition) and transitional milk (collected 5 days postpartum) showed that they were almost identical. In total, six peptides, αs1‐CN (f16‐23) (RPKHPIKH), αs1‐CN (f16‐24) (RPKHPIKHQ), αs1‐CN (f17‐25) (PKHPIKHQG), αs1‐CN (f46‐52) (VFGKEKV), αs1‐CN (f94‐105) (HIQKEDVPSER), and β‐CN (f121‐128) (HKEMPFPK), were identified. One of the major peptides, the N‐terminal fragment of αs1‐casein, varied structurally during early lactation: αs1‐CN (f17‐25) (PKHPIKHQG) and αs1‐CN (f16‐23) (RPKHPIKH)/αs1‐CN (f16‐24) (RPKHPIKHQ) were found in colostrum and transitional milk, respectively. A chemically synthesized peptide, αs1‐CN (f16‐23) (RPKHPIKH), inhibited apoptosis of bovine granulosa cells induced by serum‐free conditions in a dose‐dependent manner, in consequence of caspase‐3 and caspase‐9 suppressions. The physiological function of the peptide remains unclear, but it may have potential use as pharmaceutical agent and as an anti‐apoptotic agent in cell culture medium. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
4.
The colonization of liquid surfaces as floating biofilms or pellicles is a bacterial adaptation to optimally occupy the airliquid (A-L) niche. In aerobic heterotrophs, pellicle formation is beneficial for the utilization of O2 and nonpolar organic compounds. Pseudomonas alkylphenolica KL28, an alkylphenol degrader, forms flat circular pellicles that are 0.3–0.5 mm in diameter. In this study, we first monitored the pellicle developmental patterns of multicellular organization from the initial settlement stage. The pellicles developed by clonal growth and mutants for flagella and pilus formation established normal pellicles. In contrast, the mutants of an epm gene cluster for biosynthesis of alginate-like polymer were incompetent in cell alignment for initial two-dimensional (2D) pellicle growth, suggesting the role of the Epm polymer as a structural scaffold for pellicle biofilms. Microscopic observation revealed that the initial 2D growth transited to multilayers by an accumulated self-produced extracellular polymeric substance that may exert a constraint force. Electron microscopy and confocal laser scanning microscopy revealed that the fully matured pellicle structures were densly packed with matrix-encased cells displaying distinct arrangements. The cells on the surface of the pellicle were relatively flat, and those inside were longitudinally cross-packed. The extracellular polysaccharide stained by Congo red was denser on the pellicle rim and a thin film was observed in the open spaces, indicative of its role in pellicle flotation. Our results demonstrate that P. alkylphenolica KL28 coordinately dictates the cell arrangements of pellicle biofilms by the controlled growth of constituent cells that accumulate extracellular polymeric substances.  相似文献   
5.
Mature adults of Ascarops strongylina (Nematoda: Spirocercidae) were collected from a Manchurian zokor, Myospalax psilurus (Rodentia: Cricetidae), in Mongolia. This is the second record of adult A. strongylina from wild rodents and the first for M. psilurus as a definitive host of this nematode. Remnants of ground crustaceans (Porcellio sp.) and a dung beetle (Onthophagus sp.) were also found in the stomach of the zokor.  相似文献   
6.
A bovine lipocalin, previously identified as a putative odorant-binding protein in bovine colostrum (bcOBP), was cloned and expressed, and its monoclonal antibody was established. bcOBP was constantly secreted into milk on day of parturition until at least 10 d postpartum at a concentration of 181±39 μg/L. Besides milk, bcOBP occurred in the nasal mucus, saliva, amniotic fluid, vaginal discharge, and blood plasma. Despite its low concentration, the distribution pattern and the finding that bcOBP harbored a characteristic sequence motif, CxxxC, which is conserved among insect and mammal pheromone binding proteins, suggest that bcOBP functions as a pheromone carrier. The presence of bcOBP in the plasma at varied concentrations depending on the lactation period does not exclude the possibility that bcOBP is secreted into milk from the blood. Cross-reactivity of the monoclonal antibody indicated presence of proteins homologous to bcOBP in the colostrum of farm animals of Cetartiodactyla.  相似文献   
7.
A cat excreting Echinococcus multilocularis eggs was recently identified in Hokkaido, representing the first such observation in Japan. The cat was raised free-range and frequently ate rodents. Fecal egg examination revealed eggs of taeniids (EPG: 440) and Spirometra spp. (EPG: > 1000). PCR targeting part of the mitochondrial cytochrome c oxidase subunit I gene of E. multilocularis was positive with DNA from 3 single isolated taeniid eggs, and sequence analysis of one amplicon confirmed E. multilocularis. The results indicated that the eggs of E. multilocularis distributed in Hokkaido can be excreted in cat feces, and suggested the necessity of further studies to clarify whether the eggs excreted in cat feces are infective and thus whether cats can serve as infectious source to humans in Japan.  相似文献   
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