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41.
对种族、生活习惯不同人群的肠道菌群进行研究,寻找适宜的生态调节剂是微生态学的研究热点[1]。在我国,对汉族、彝族人群的肠道菌群研究的较多[1,2],已经能够对肠道内10余类细菌进行定量分析,同时也研制出了如促菌生、回春生、昂立1号等微生态制剂用于临床[3]。对于蒙古族人群特别是老年人的肠道微生态学研究、寻找适于本地区人群的微生态制剂,既是微生态学领域的重要任务,也是落实民族政策的必需,是开发具有针对性老年保健品的前提[4]。为此,我们于1999年8月至1999年9月对赤峰地区蒙古族、汉族老年人的肠道微生态学进行了研究。1 材料与方… 相似文献
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东北地区谷子地方品种和育成品种表型比较分析 总被引:1,自引:0,他引:1
我国东北地区谷子育种经历了从地方品种到育成品种的转变,但其具体表型性状等变化尚不清楚。本研究在敖汉旗对我国东北地区120个谷子地方品种和育成品种进行表型鉴定,并分析了遗传多样性,结果表明:东北地区谷子品种以绿幼苗、绿叶鞘、纺锤松散穗、黄粒、黄米型为主。育成品种晚熟、生物量大且高产,表现在出苗至抽穗、开花、成熟的时间以及播种至成熟的时间均极显著大于地方品种;主茎直径、叶片数、旗叶宽度均极显著大于地方品种;主穗重、主穗粒数极显著大于地方品种,主穗粒重和产量显著大于地方品种,但千粒重极显著小于地方品种,说明育成品种主要通过增加穗粒数来实现产量提升。遗传多样性指数分析发现,参试品种各性状遗传多样性指数大小顺序为:产量性状(2.0063)形态性状(1.9655)生育期(1.7238)质量性状(0.6370);地方品种护颖颜色、粒色、米色遗传多样性指数明显高于育成品种,说明谷子育种使粒色米色越来越趋于一致。基于30个性状的标准化数据,将参试品种聚为两类,聚类结果与品种来源地没有明显关联。类群Ⅰ为早熟、低产品种,且幼苗叶色、米色均为绿色和黄色;类群Ⅱ为晚熟、高产品种。根据10个主要表型性状,筛选出综合性状优良的红谷子、燕谷18等种质资源,可供东北地区谷子育种重点利用。 相似文献
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《植物生态学报》2016,40(4):327
Aims
Forest carbon storage in Nei Mongol plays a significant role in national terrestrial carbon budget due to its large area in China. Our objectives were to estimate the carbon storage in the forest ecosystems in Nei Mongol and to quantify its spatial pattern.
Methods
Field survey and sampling were conducted at 137 sites that distributed evenly across the forest types in the study region. At each site, the ecosystem carbon density was estimated thorough sampling and measuring different pools of soil (0-100 cm) and vegetation, including biomass of tree, grass, shrub, and litter. Regional carbon storage was calculated with the estimated carbon density for each forest type.
Important findings
Carbon storage of vegetation layer in forests in Nei Mongol was 787.8 Tg C, with the biomass of tree, litter, herbaceous and shrub accounting for 93.5%, 3.0%, 2.7% and 0.8%, respectively. Carbon density of vegetation layer was 40.4 t·hm-2, with 35.6 t·hm-2 in trees, 2.9 t·hm-2 in litter, 1.2 t·hm-2 in herbaceous and 0.6 t·hm-2 in shrubs. In comparison, carbon storage of soil layer in forests in Nei Mongol was 2449.6 Tg C, with 79.8% distributed in the first 30 cm. Carbon density of soil layer was 144.4 t·hm-2. Carbon storage of forest ecosystem in Nei Mongol was 3237.4 Tg C, with vegetation and soil accounting for 24.3% and 75.7%, respectively. Carbon density of forest ecosystems in Nei Mongol was 184.5 t·hm-2. Carbon density of soil layer was positively correlated with that of vegetation layer. Spatially, both carbon storage and carbon density were higher in the eastern area, where the climate is more humid. Forest reserves and artificial afforestations can significantly improve the capacity of regional carbon sink. 相似文献
Forest carbon storage in Nei Mongol plays a significant role in national terrestrial carbon budget due to its large area in China. Our objectives were to estimate the carbon storage in the forest ecosystems in Nei Mongol and to quantify its spatial pattern.
Methods
Field survey and sampling were conducted at 137 sites that distributed evenly across the forest types in the study region. At each site, the ecosystem carbon density was estimated thorough sampling and measuring different pools of soil (0-100 cm) and vegetation, including biomass of tree, grass, shrub, and litter. Regional carbon storage was calculated with the estimated carbon density for each forest type.
Important findings
Carbon storage of vegetation layer in forests in Nei Mongol was 787.8 Tg C, with the biomass of tree, litter, herbaceous and shrub accounting for 93.5%, 3.0%, 2.7% and 0.8%, respectively. Carbon density of vegetation layer was 40.4 t·hm-2, with 35.6 t·hm-2 in trees, 2.9 t·hm-2 in litter, 1.2 t·hm-2 in herbaceous and 0.6 t·hm-2 in shrubs. In comparison, carbon storage of soil layer in forests in Nei Mongol was 2449.6 Tg C, with 79.8% distributed in the first 30 cm. Carbon density of soil layer was 144.4 t·hm-2. Carbon storage of forest ecosystem in Nei Mongol was 3237.4 Tg C, with vegetation and soil accounting for 24.3% and 75.7%, respectively. Carbon density of forest ecosystems in Nei Mongol was 184.5 t·hm-2. Carbon density of soil layer was positively correlated with that of vegetation layer. Spatially, both carbon storage and carbon density were higher in the eastern area, where the climate is more humid. Forest reserves and artificial afforestations can significantly improve the capacity of regional carbon sink. 相似文献
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【目的】植绥螨是蓟马等害虫(螨)的重要捕食性天敌,在当前生物防治中应用广泛,本研究旨在为本地植绥螨资源的开发利用及筛选出控制西花蓟马Frankliniella occidentalis最有效的植绥螨天敌提供依据。【方法】以西花蓟马为猎物,在室内温度(25±1)℃、光照16L︰8D、相对湿度80%±5%的条件下,比较了内蒙古本地植绥螨种类有益真绥螨Euseius utilis Liang et Ke、苏氏副伦绥螨Paraseiulus soleiger Ribaga和巴氏新小绥螨Neoseiulus barkeri Hughes及目前应用的植绥螨斯氏钝绥螨Amblyseius swirskii Athias-Henriot、东方钝绥螨A.orientalis Ehara和黄瓜新小绥螨N.cucumeris Oudemans取食西花蓟马后的发育历期和生殖潜力,并组建了实验种群生命表以评价各类植绥螨的捕食潜能。【结果】有益真绥螨的日均产卵量(1.67±0.02)粒和黄瓜新小绥螨的日均产卵量(1.58±0.06)粒相近且无显著差异,仅次于斯氏钝绥螨(1.69±0.07)粒;有益真绥螨其子代雌雄性比与黄瓜新小绥螨的性比也相同(1.63︰1),低于斯氏钝绥螨(1.77︰1)和巴氏新小绥螨(1.64︰1);有益真绥螨的世代平均周期最短(T=19.36 d),内禀增长率(rm=0.16)和周限增长率(λ=1.17)均最大,种群倍增时间最短(t=4.33 d)。【结论】有益真绥螨以西花蓟马为食后种群数量增长的潜力强于其他5种植绥螨,是本地防治西花蓟马较有潜力的植绥螨种类。 相似文献
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目的:探讨将纳米铂黑作为电极镀层的细胞毒性,初步评估铂黑电镀电极长期植入生物体内的安全性。方法:分别改变混悬液浓度(0.1 mg、0.2 mg、0.3 mg/m L铂黑混悬液)对L-929成纤维细胞培养24 h、48 h、72 h,显微镜下观察细胞形态变化并通过MTS法计算细胞相对增殖率,对细胞毒性进行评级。结果:0.2 mg/m L、0.3 mg/m L的铂黑混悬液中L-929成纤维细胞变成圆形、胞核固缩,细胞稀少,贴壁差;在0.1 mg/m L的铂黑混悬液中上述细胞形态变化则较轻微。0.1 mg/m L的铂黑混悬液细胞毒性为0~2级,且随时间延长而毒性逐渐减弱并呈现出无细胞毒性;0.2 mg/m L、0.3 mg/m L的铂黑混悬液细胞毒性为3~4级,不随时间变化。结论:纳米铂黑其质量体积浓度低于0.1 mg/m L时具有较好的生物相容性。 相似文献
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中国菊科植物上的柄锈菌属一新种和一新记录(英文) 总被引:1,自引:0,他引:1
报道了中国菊科植物上柄锈菌属1新种和1新记录变种。拐轴鸦葱Scorzonera divaricata上的苏尼特柄锈菌Puccinia sonidensis为新种;猫儿菊Hypochaeris ciliata上的山柳菊柄锈菌猫儿菊变种Puccinia hieracii var.hypochaeridis为中国新记录。提供了详细的形态描述和线条图。研究标本保存在赤峰学院菌物标本室(CFSZ)和中国科学院菌物标本馆(HMAS)。 相似文献