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排序方式: 共有192条查询结果,搜索用时 31 毫秒
101.
Ji Sook Kang Il-Whan Choi Min Ho Han Dae-Sung Lee Gi-Young Kim Hye Jin Hwang Byung Woo Kim Cheol Min Kim Young Hyun Yoo Yung Hyun Choi 《Marine drugs》2015,13(5):2666-2679
This study was designed to examine the protective effects of the marine brown algae Petalonia binghamiae against oxidative stress-induced cellular damage and to elucidate the underlying mechanisms. P. binghamiae methanol extract (PBME) prevented hydrogen peroxide (H2O2)-induced growth inhibition and exhibited scavenging activity against intracellular reactive oxygen species (ROS) induced by H2O2 in mouse-derived C2C12 myoblasts. PBME also significantly attenuated H2O2-induced comet tail formation in a comet assay, histone γH2A.X phosphorylation, and annexin V-positive cells, suggesting that PBME prevented H2O2-induced cellular DNA damage and apoptotic cell death. Furthermore, PBME increased the levels of heme oxygenase-1 (HO-1), a potent antioxidant enzyme, associated with the induction of nuclear factor-erythroid 2 related factor 2 (Nrf2). However, zinc protoporphyrin IX, a HO-1 competitive inhibitor, significantly abolished the protective effects of PBME on H2O2-induced ROS generation, growth inhibition, and apoptosis. Collectively, these results demonstrate that PBME augments the antioxidant defense capacity through activation of the Nrf2/HO-1 pathway. 相似文献
102.
Marta Dec Andrzej Wernicki Andrzej Puchalski Renata Urban-Chmiel Adam Wa?ko 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(1):33-38
Conglutinin is a high molecular-weight lectin originally detected in bovine serum. It belongs to the family of collectins that bind sugar residues in a Ca2+-dependent manner and are effector molecules in innate immunity. Conglutinin appears to play an important role in immune defense mechanisms, showing antiviral and antibacterial activities when tested in vivo and in vitro. The present study evaluated the effect of conglutinin on the respiratory bursts in bovine peripheral phagocytes. Using nitroblue tetrazolium and hydrogen peroxide assays, we showed that sugar ligand-bound conglutinin stimulated the production of superoxide and H2O2 in granulocytes whereas the non-sugar-bound form of conglutinin inhibited these processes. These results indicate that both forms of conglutinin are able to interact with surface leukocyte receptors but have opposite effects on phagocytic activity. Our findings suggest that conglutinin bound to sugar residues on microbial surfaces can induce oxygen burst in phagocytes, and thereby mediates the elimination of pathogens and prevents the spread of infection. 相似文献
103.
Heather L. Priest Nita L. Irby Donald H. Schlafer Thomas J. Divers Bettina Wagner Amy L. Glaser Yung‐Fu Chang Mary C. Smith 《Veterinary ophthalmology》2012,15(6):398-405
Borrelia burgdorferi, the etiologic agent of Lyme disease is a tick born spirochetal infection. Clinical signs of Lyme borreliosis are uncommon in horses, but when present they are often vague and nonspecific. In horses, Lyme borreliosis has been implicated in musculoskeletal, neurological, reproductive, and ocular disorders, including uveitis, but definitive diagnosis can be challenging as the causative agent is rarely isolated and serologic tests can be unreliable and do not confirm active disease. Here, we report two cases of equine uveitis associated with B. burgdorferi based on the identification of spirochetes within ocular fluids and confirmed with PCR testing. The two cases illustrate some of the challenges encountered in the recognition and diagnosis of equine Lyme borreliosis. Although only one of many possible causes of equine uveitis, Lyme disease should be considered a differential diagnosis, especially in endemic areas. Given the possibility for false negative results of serum tests during uveitis associated with B. burgdorferi and the failure of such tests to confirm active infection, a combination of cytologic assessment, antibody, and/or PCR testing of ocular fluids may be worthwhile if the clinical suspicion for Lyme uveitis is high. 相似文献
104.
Genetic correlations between male reproductive traits and growth traits in growth performance tested Duroc,Landrace and Yorkshire breed boars 下载免费PDF全文
Male‐related traits at 180–225 days of age for 6464 grow‐finish performance tested boars were measured from 2000 to 2016. Heritability estimates and genetic correlations among average daily gain, feed efficiency, back fat thickness, teat counts, mounting libido, leg locomotion, penile length, sperm motility, sperm concentration and total sperm counts were estimated by VCE software using a multiple traits animal model in each breed. Growth‐tested boars had heritability estimates of male reproductive traits in 0.34–0.56 of teat counts, 0.12–0.20 of libido, 0.08–0.12 of locomotion, 0.17–0.58 of penile length, 0.04–0.21 of sperm motility and concentration, 0.17–0.30 of total sperm counts. Total sperm counts were genetically positively correlated with penile length in all breeds. Boars with higher total sperm counts had genetically better libido and locomotion. Genetic correlation between feed efficiency and sperm motility and feed efficiency and sperm concentration were positive in Duroc and negative in Landrace and Yorkshire. Sperm motility and concentration were genetically negatively correlated with average daily gain in Yorkshire. Male reproductive traits of imported breeds could be improved with care in the change of growth traits, especially in Yorkshire. 相似文献
105.
106.
合肥市环城公园景观调查及存在问题研究 总被引:1,自引:0,他引:1
誉为“翡翠项链”的环城公园不仅传承了合肥的历史文化,更作为市民的开放公园,营造出新时代人与自然环境的和谐。通过对其中包河、银河、西山、黑池坝、琥珀潭等诸景区的考察和调研,对合肥市环城公园进行景观分析,提出景区设计和生态效应改进的若干建议。 相似文献
107.
108.
Yung Kun KIM Daisuke KOYABU Hang LEE Junpei KIMURA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1427-1435
The water deer (Hydropotes inermis) has conventionally been classified
into two subspecies according to geographic distribution and pelage color pattern:
H. i. inermis from China and H. i. argyropus from
Korea. However, the results of a recent molecular study have called this into question. To
further reappraise this classification, we examined morphological variation in
craniodental measurements of these 2 subspecies. Results of univariate and multivariate
analyses demonstrated that these 2 subspecies are not well-differentiated, suggesting that
individuals of the 2 populations share common morphological traits. Despite the
distribution of the subspecies at different latitudes, no clear morphocline was detected,
suggesting that Bergmann’s rule does not apply in this case. Discriminant analysis
indicated that the characteristics of individuals are shared by both populations,
suggesting that not all individuals can be assigned to their original population. Results
of principal component analysis showed that the two populations shared more than 75% of
individuals, congruent with the “75% rule” of subspecies classification. In both the
neighbor-joining and unweighted pair group methods with arithmetic mean cluster analyses,
specimens of H. i. argyropus and H. i. inermis were
highly mixed within the cladograms. These results suggest that the overall morphological
variation in the 2 subspecies overlaps considerably and that there is no coherent
craniofacial difference between the 2 groups. The present findings combined with prior
observations from molecular biogeography point out that the taxonomic division of water
deer into 2 subspecies should be revisited. 相似文献
109.
Luis E Escobar A Townsend Peterson Monica Pape? Myriam Favi Veronica Yung Olivier Restif Huijie Qiao Gonzalo Medina-Vogel 《Veterinary research》2015,46(1)
Rabies remains a disease of significant public health concern. In the Americas, bats are an important source of rabies for pets, livestock, and humans. For effective rabies control and prevention, identifying potential areas for disease occurrence is critical to guide future research, inform public health policies, and design interventions. To anticipate zoonotic infectious diseases distribution at coarse scale, veterinary epidemiology needs to advance via exploring current geographic ecology tools and data using a biological approach. We analyzed bat-borne rabies reports in Chile from 2002 to 2012 to establish associations between rabies occurrence and environmental factors to generate an ecological niche model (ENM). The main rabies reservoir in Chile is the bat species Tadarida brasiliensis; we mapped 726 occurrences of rabies virus variant AgV4 in this bat species and integrated them with contemporary Normalized Difference Vegetation Index (NDVI) data from the Moderate Resolution Imaging Spectroradiometer (MODIS). The correct prediction of areas with rabies in bats and the reliable anticipation of human rabies in our study illustrate the usefulness of ENM for mapping rabies and other zoonotic pathogens. Additionally, we highlight critical issues with selection of environmental variables, methods for model validation, and consideration of sampling bias. Indeed, models with weak or incorrect validation approaches should be interpreted with caution. In conclusion, ecological niche modeling applications for mapping disease risk at coarse geographic scales have a promising future, especially with refinement and enrichment of models with additional information, such as night-time light data, which increased substantially the model’s ability to anticipate human rabies.
Electronic supplementary material
The online version of this article (doi:10.1186/s13567-015-0235-7) contains supplementary material, which is available to authorized users. 相似文献110.
We present a brief introduction to FT‐Raman spectroscopy and examples of its use in cereal science for readers not familiar with Raman spectroscopy. We illustrate the use of FT‐Raman spectroscopy as an analytical tool to measure the degree of chemical modification of chemically modified starches and as a technique to determine conformational and structural changes in plant proteins under different environmental conditions. We briefly describe other applications of Raman spectroscopy in cereal science. 相似文献