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31.
何鑫 《信阳农业高等专科学校学报》2014,(4):85-87
本文在对信阳民间艺术文化资源梳理的基础上,探讨了目前信阳民间艺术文化传承与保护中存在的问题,进而提出相关对策。 相似文献
32.
Sophie Miyumo Chrilukovian B. Wasike Evans D. Ilatsia Jörn Bennewitz Mizeck G. Chagunda 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2023,140(1):106-120
This study aimed at investigating the influence of genetic and non-genetic factors on immune traits to inform on possibilities of genetic improvement of disease resistance traits in local chicken of Kenya. Immune traits such as natural and specific antibodies are considered suitable indicators of an individual's health status and consequently, used as indicator traits of disease resistance. In this study, natural antibodies binding to Keyhole Limpet Hemocyanin (KLH-NAbs) was used to measure general disease resistance. Specific antibodies binding to Newcastle disease virus (NDV-IgG) post vaccination was used to measure specific disease resistance. Titers of KLH-NAbs isotypes (KLH-IgM, KLH-IgG and KLH-IgA) and NDV-IgG were measured in 1,540 chickens of different ages ranging from 12 to 56 weeks. A general linear model was fitted to determine the effect of sex, generation, population type, phylogenetic cluster, line, genotype and age on the antibody traits. A multivariate animal mixed model was fitted to estimate heritability and genetic correlations among the antibody traits. The model constituted of non-genetic factors found to have a significant influence on the antibody traits as fixed effects, and animal and residual effects as random variables. Overall mean (±SE) concentration levels for KLH-IgM, KLH-IgG, KLH-IgA and NDV-IgG were 10.33 ± 0.04, 9.08 ± 0.02, 6.00 ± 0.02 and 10.12 ± 0.03, respectively. Sex, generation and age (linear covariate) significantly (p < 0.05) influenced variation across all the antibody traits. Genotype effects (p < 0.05) were present in all antibody traits, apart from KLH-IgA. Interaction between generation and line was significant (p < 0.05) in KLH-IgM and NDV-IgG while nesting phylogenetic cluster within population significantly (p < 0.05) influenced all antibody traits, apart from KLH-IgA. Heritability estimates for KLH-IgM, KLH-IgG, KLH-IgA and NDV-IgG were 0.28 ± 0.08, 0.14 ± 0.06, 0.07 ± 0.04 and 0.31 ± 0.06, respectively. There were positive genetic correlations (0.40–0.61) among the KLH-NAbs while negative genetic correlations (−0.26 to −0.98) were observed between the KLH-NAbs and NDV-IgG. Results from this study indicate that non-genetic effects due to biological and environmental factors influence natural and specific antibodies and should be accounted for to reduce bias and improve accuracy when evaluating the traits. Subsequently, the moderate heritability estimates in KLH-IgM and NDV-IgG suggest selection possibilities for genetic improvement of general and specific immunity, respectively, and consequently disease resistance. However, the negative correlations between KLH-NAbs and NDV-IgG indicate the need to consider a suitable approach that can optimally combine both traits in a multiple trait selection strategies. 相似文献
33.
M. Shamim Hasan ZAHID Sharda Prasad AWASTHI Atsushi HINENOYA Shinji YAMASAKI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):535-540
To search natural compounds having inhibitory effect on bacterial growth is important,
particularly in view of growing multidrug resistant (MDR) strains of bacterial pathogens.
Like other bacterial pathogens, MDR Vibrio cholerae, the causative agent
of diarrheal disease cholera, is becoming a great concern. As an approach of searching new
antimicrobial agents, here, we show that anethole, a well-studied natural component of
sweet fennel and star anise seeds, could potentially inhibit the growth of MDR O1 El Tor
biotype, the ongoing 7th cholera pandemic variant strains of toxigenic V.
cholerae. The minimum inhibitory concentration (MIC) of anethole against
diverse O1 El Tor biotype strains is evaluated as 200
µg/ml. Moreover, the effect of anethole is
bactericidal and exerts rapid-killing action on V.
cholerae cells. This study is the first report which demonstrates
that anethole, purified from natural compound, is a potent inhibitor of growth of
toxigenic V. cholerae. Our data suggest that anethole could be a
potential antimicrobial drug candidate, particularly against MDR V.
cholerae mediated infections. 相似文献
34.
35.
甘肃陇南地震扰动区植被群落特征 总被引:1,自引:0,他引:1
地震扰动对当地生态环境造成极大的破坏,引起植被群落种类组成、群落结构的变化,本研究采用样带结合海拔梯度的方法,于2013年8-9月,调查和研究了甘肃陇南武都区清水沟植被群落的种类组成、群落结构受地震扰动后的现状。结果表明,研究区内共发现34种植物,分属16科30属,主要以禾本科和菊科植物为主,群落垂直结构明显,大体分为3层;植物群落中多年生草本植物种类最多,是优势生活型,其次是灌木、藤本,无乔木分布;Shannon-Wiener多样性指数(H')和Pielou均匀度指数(E)表现为中坡位下坡位上坡位,Simpson优势度指数(D)表现为上坡位下坡位中坡位。 相似文献
36.
采用国家标准法对西藏天然草原茎直黄芪(Astragalus strictus)、甘肃棘豆(Oxytropis kansuensis)、毛瓣棘豆(Oxytropis sericopetala)、瑞香狼毒(Stellera chamaejasme)和藏橐吾(Ligularia rumicifolia)5种主要有毒植物不同物候期常规营养成分和矿质元素含量进行测定。结果显示,在5种植物中,粗蛋白平均含量以茎直黄芪最高,其次为甘肃棘豆,且两者粗蛋白含量均超过19%;茎直黄芪中花期粗蛋白含量最高,花前期最低,花期和花果期差异不显著(P0.05);而甘肃棘豆中粗蛋白含量以花前期最高,花果期最低,花前期和花期差异不显著。粗纤维平均含量由高到低依次为毛瓣棘豆、藏橐吾、茎直黄芪、甘肃棘豆和瑞香狼毒,且均以花果期最高,花前期最低。5种植物Mg、Fe、Cu、Mn和Zn含量均以花前期最高,花期次之,花果期最低;但Se含量花果期相对较高。由此得出,茎直黄芪和甘肃棘豆营养较为丰富,具有潜在饲用价值,毛瓣棘豆、瑞香狼毒和藏橐吾营养价值偏低。 相似文献
37.
外来树种马占相思自然繁殖更新研究 总被引:3,自引:3,他引:3
调查马占相思人工林的自然更新情况,在国内首次发现马占相思存在种子成苗方式的自然更新.但马占相思的自然更新受立地条件制约:只有在林缘的裸露立地条件下,马占相思的种子才能萌发成苗.马占相思16年生单株在45°扇形单方向更新扩散的最远距离为17.5 m,更新繁殖的株数最多有26株;扩散距离与扩散株数之间没有明显的相关性.1987年穴状埋根造林的马占相思,其林缘更新扩散的最远距离为10.0 m,更新繁殖的株数最多有3株;1997年穴状埋根造林的马占相思,其林缘更新扩散的最远距离为3.0 m,更新繁殖的株数最多有14株.用小样方法调查马占相思人工林下乡土乔木、灌木和草本植物的自然更新.结果表明,在马占相思林分内,共发现12种乔木树种、3种灌木树种和8种草本植物,这些乡土植物均表现为生活力强.研究结果表明,马占相思在靠近水源的裸露立地条件下可以自然更新,更新的方式为种子繁殖;马占相思不影响乡土植物的正常生长. 相似文献
39.
40.
长序榆天然更新调查研究 总被引:5,自引:0,他引:5
对福建省南平市来舟镇东山村残存的珍稀濒危树种长序榆的天然更新状况进行研究,结果表明:长序榆大树虽然生长旺盛,但林下天然更新不良。长序榆果实风播有效距离仅为30m,且由于它是阳性树种,不耐蔽荫,在阳光不足的林下种子难于成苗,幼苗难以成树,天然更新能力弱,这些是它种群数量少,处于濒危状态的主要原因。 相似文献