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971.
Burgener IA König A Allenspach K Sauter SN Boisclair J Doherr MG Jungi TW 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2008,22(3):553-560
BACKGROUND: Inflammatory bowel disease (IBD) is thought to result from a dysregulated interaction between the host immune system and commensal microflora. Toll-like receptors (TLRs) recognize microbe-associated molecular patterns (MAMPs), but their role in enteropathies in dogs is unknown. HYPOTHESIS: That there is a dysregulation of TLRs recognizing bacterial MAMPs in dogs with IBD. ANIMALS: Sixteen healthy beagles and 12 dogs with steroid-treated (ST) and 23 dogs with food-responsive (FR) diarrhea. METHODS: Prospective, observational study. mRNA expression of canine TLR2, 4, and 9 was evaluated by quantitative real-time RT-PCR in duodenal and colonic biopsies obtained before and after standard therapy. Samples from control dogs were taken at necropsy, with additional biopsies of stomach, jejunum, ileum, and mesenteric lymph node in 6 dogs. RESULTS: There were significant differences (P< or = .017) in expression of TLR2, 4, and 9 between the 6 sampled locations in healthy control dogs (lymph node > small intestine > or = colon). Before therapy, ST expressed more mRNA than control dogs for all 3 receptors (P < .05). There were no significant differences between pretreatment and posttreatment values, even though 32/35 dogs improved clinically. No associations were found when comparing receptor mRNA expression with either histology or clinical activity scores. CONCLUSIONS AND CLINICAL IMPORTANCE: Bacteria-responsive TLR2, 4, and 9 are upregulated in duodenal and colonic mucosa in IBD. This might lead to increased inflammation through interaction with the commensal flora. The absence of significant changes after therapy despite clinical improvement might point toward the existence of a genetic predisposition to IBD as described in human IBD. 相似文献
972.
Innate immunity and host defense peptides in veterinary medicine 总被引:1,自引:0,他引:1
Linde A Ross CR Davis EG Dib L Blecha F Melgarejo T 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2008,22(2):247-265
Recent years have witnessed a surge in interest directed at innate immune mechanisms. Proper conceptualization of the key elements of innate immunity, however, is still a work in progress, because most research in immunology traditionally has been focused on components of the acquired immune response. The question of why an animal stays healthy in a world filled with many dangers is perhaps as interesting as why it sometimes surrenders to disease. Consequently, studies with an increased focus on inborn mechanisms of animal host defense may help further the development of appropriate preventative and therapeutic measures in veterinary medicine. Host defense peptides (HDPs) are central effector molecules of innate immunity, and are produced by virtually all living species throughout the plant and animal kingdoms. These gene-encoded peptides play a central role in multiple, clinically relevant disease processes. Imbalances in the expression of HDPs can lead to overt pathology in different organ systems and cell types in all species studied. In addition, HDPs are an ancient group of innate chemical protectors, which are now evaluated as model molecules for the development of novel natural antibiotics and immunoregulatory compounds. This review provides an overview of HDPs and is aimed at veterinary practitioners as well as basic researchers with an interest in comparative immunology involving small and large animal species. 相似文献
973.
为了进一步研究蜱吸血时唾液腺的基因表达调控机制,并为蜱疫苗的制备筛选功能性抗原,本试验对从亚洲璃眼蜱雌蜱吸血前后唾液腺消减文库中筛选出的一个具有Poly(A)尾的EST序列P27进行了研究。首先运用RACE技术扩增出该基因的5′端,在此基础上设计引物,扩增出该基因全长,此基因全长827bp,其开放阅读框从第35个碱基始至第706个碱基止,预测分子量为27.28ku,等电点4.22。生物信息学结构分析表明该基因含有跨膜区及多个活性位点,可能与细胞内DNA的转录相关;该基因与现有其他基因同源性很小,为一新基因;RT-PCR结果显示该基因在半饱血雌蜱的唾液腺、蜱壳、中肠均有表达,但在壳中表达丰度稍低。本研究克隆的P27基因序列已登录GenBank,序列号为EU180067。 相似文献
974.
为评估DNA随机扩增多态性标记在中国对虾遗传连锁图谱构建中的应用前景,利用中国对虾单对交配亲本及其子二代材料,对RAPD标记及其遗传规律进行了研究。22条RAPD随机引物扩增结果的统计分析表明,标记在中国对虾F2的遗传规律可归为不分离标记和分离标记:不分离标记,指在亲本和后代中均不分离的标记,占总位点的54.1%;分离标记占总位点的45.9%。其中,分离标记又包括符合孟德尔遗传分离的标记、偏离孟德尔遗传分离标记和异常分离标记。符合孟德尔分离的标记中,分离比例为3:1的标记占分离标记的14.7%;总的1:1标记占分离标记的64.7%;偏离孟德尔分离和异常分离的标记分别占分离标记的11.7%和8.9%。在这些分离的标记中,有76.5%的位点在“双假测交理论”的策略中适合构建中国对虾的遗传连锁图谱,这为以中国对虾F2为作图群体,并利用RAPD标记构建中国对虾遗传连锁图谱提供了理论支持。 相似文献
975.
长白山落叶松人工天然混交林空间格局研究 总被引:1,自引:0,他引:1
吕林昭 《内蒙古林业调查设计》2007,30(3):57-62
用点格局分布、混交度和大小比数3个林分空间结构参数,分析了长白山落叶松人工林与天然林木混交的林分空间结构。结果表明:①空间分布:入侵的天然树种呈现明显的聚集分布,落叶松除15m时的聚集分布外均呈现显著的随机分布,林分整体呈现小尺度的聚集分布,在大尺度下呈随机分布。②混交度:林分的混交度为0.84,说明它是一个由不同树种呈现强度混交结构状态组成的复杂森林群落。③大小比数:落叶松占据了优势地位,入侵的天然树种冷杉优势最明显,榆树最不具优势。 相似文献
976.
李慧敏 《辽宁农业职业技术学院学报》2003,5(2):30
为充分利用光、热等自然资源 ,提高土地利用效率 ,减少菜地病虫害的发生 ,介绍几种先进、实用的蔬菜与大田作物复种模式 ,以期对农民增产增收提供参考。 相似文献
977.
本文报告应用酶泳技术检测中国大陆云南、四川、湖北、湖南、江西、江苏、安徽七地自然隔离群日本血吸虫的LDH、MDH、ME、6PG、6GP、GI1、IDH、PGI、ADK、HEX和EST11种同工酶酶谱情况。其中七地自然隔离群日本血吸虫的MDH、ME、6PG、G6P、GD1、IDH、PGI、ADK及HEX9种同工酶图谱相同,说明我国大陆七地自然隔离群日本血吸虫结构基本相同,其亲缘关系密切。在LDH说明 相似文献
978.
979.
In Maine and other heavily forested states, existing land cover maps quickly become dated due to forest harvesting and land use conversion; therefore, these maps may not adequately reflect landscape properties and patterns relevant to current resource management and ecosystem studies. By updating an older land cover product (the 1993 Maine GAP map) using Landsat imagery and established forest change detection techniques, we demonstrate a practical and accurate means of providing contemporary, spatially explicit forest cover data needed to quantify landscape change. For a 1.8 million hectares study area in northern Maine, we quantify the accuracy of forest harvest classes and compare mapped harvest and regeneration area between the 2004 GAP update product and the 2004 Maine Landcover Dataset (MeLCD), a map recently developed in coordination with the 2001 National Land-Cover Database (NLCD). For the period 1995–2004, the overall harvest/non-harvest accuracy of the GAP update map is 87.5%, compared to 62.1% for the MeLCD. Producer and user accuracy for harvest detection is 92.4% and 89.7%, respectively for the GAP update, and 48.8% and 92.5% for the MeLCD. Mapped harvest area differs considerably, reflecting a systematic under-representation of recent harvest activity on the part of the MeLCD. By integrating older land cover data, the GAP update retains the forest disturbance legacies of the late 1970s through the early 1990s while simultaneously depicting 2004 forest composition for harvested and regenerating stands. In contrast, the MeLCD (and 2001 NLCD) over-represents the area and connectivity of older forest (undisturbed since the late 1970s), and provides no forest composition information for mapped forest regeneration. Systematic misclassification of forest age classes and harvest history has serious implications for studies focused on wildlife habitat modeling, forest inventory, and biomass or carbon stock estimation. We recommend the integration of older land cover data and time-series forest change detection for retention of harvest or disturbance classes when creating new forest and land cover maps. 相似文献
980.
The fishery for California groundfishes is managed using broad species complexes, although some non-groundfish species are managed similarly due to the perception of shared behavioral characteristics. This study integrates acoustic telemetry and a GIS to quantify movement patterns of one such species, the ocean whitefish (Caulolatilus princeps) in a marine protected area. Seventeen ocean whitefish were tagged and actively tracked over multiple 24-h periods to measure fine-scale movement patterns. Home ranges based on 95% kernel utilization distributions averaged 20,439 ± 28,492 (±S.D.) m2. Fish were active during the day, foraging over sand habitat at depths averaging 21 ± 8 m, but were inactive at night, taking refuge near rocky reefs at depths averaging 15 ± 7 m. Seventeen additional fish were tagged with coded acoustic transmitters and passively tracked using automated underwater acoustic receivers for up to 1 year. Approximately 75% of these fish exhibited long-term (1 year) fidelity to home ranges in the study area. Results suggest that MPAs can be an effective means of protecting populations of ocean whitefish and based on their habitat associations, ocean whitefish can be managed separately from other reef associated groundfishes. 相似文献