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LI Qin CHEN Yu-cun ZHAO Feng-yong ZHANG Jia-min ZHANG Shu-hui ZHU Zi-yan 《中国畜牧兽医》2016,43(7):1850-1855
In this study,we aimed to determine whether bear had different blood group systems.Whole blood samples were collected from 40 Asiatic Black bears in Fujian province,China.Tube method was used to detect antibodies in plasma,and antibody isotype was determined with 2-mercaptoethanol.Plasma was further analyzed by mass spectrometry.The plasma from four bears had antibodies,possibly IgM isoform,which could agglutinate RBCs from 30 bears.Blood samples from 10 bears were tested by human blood typing reagents.The results showed that 4 bears had blood type like human type O,while 6 bears had like human type B.Plasma protein had extensive homology to serum albumin-like isoform 1 found in giant panda (Ailuropodamelanoleuca).We suggested that Asiatic Black bear might have at least one blood group system with two blood types.If the sick bear needs blood transfusion,a cross-matching test was necessary.Moreover,giant panda might receive blood from Asiatic Black bear in case of emergency. 相似文献
84.
利用卡庆斯基制、美国制、中国制3种土粒分级标准对张家口葡萄产区的30个采样点进行土壤质地命名,并通过对比分析得出中国制是该区最适的土壤质地分类方法。现对吸湿水含量与土壤各粒级微粒百分含量的关系做了探测性研究,得出吸湿水和土壤中小于0.01 mm的粒径含量之间拟合曲线方程为:Y=20.272e0.207x,可根据此方程应用卡庆斯基制确定土壤质地;吸湿水和土壤中1~0.05 mm0、.05~0.002 mm粒径含量的拟合曲线方程分别为:y=22.018x2-105.323x+156.381,y=-18.304x2+86.495x-49.536,又可根据这2个方程利用美国制确定土壤质地名称。这些为用简易方法鉴定土壤质地类型提供科学依据。 相似文献
85.
概述了达川区蔬菜生产全程社会化服务的现状、取得成效及主要措施,分析了存在的问题,并提出了增加补助环节、提高补助标准、培育服务主体、创新服务机制的发展对策。 相似文献
86.
镉对草莓幼苗根尖氧化系统和基因组DNA损伤的影响 总被引:4,自引:1,他引:4
采用随机扩增多态性DNA(RAPD)技术和生理生化方法检测镉胁迫对草莓幼苗根尖氧化系统和DNA多态性的影响。结果表明,用5、10和15 mg · L-1镉(CdCl2 · 2.5H2O)处理6 d后,草莓幼苗根伸长及根系中可溶性蛋白质含量均受到抑制,根尖活性氧爆发(超氧阴离子产生速率升高和过氧化氢含量增加),超氧化物歧化酶、过氧化物酶和过氧化氢酶活性下降,DNA增色效应减少。选用8条寡核苷酸引物(10 bp)对草莓幼苗根尖细胞中基因组DNA进行RAPD扩增,对照组图谱中可分辨出88条RAPD谱带,其分子量为150 ~ 3 500 bp,处理组与对照组RAPD图谱之间存在明显差异,且与镉浓度之间存在剂量效应关系。镉影响草莓幼苗根尖细胞中基因组模板的稳定性,活性氧爆发和DNA交联是根尖DNA损伤的主要原因,利用RAPD技术获得的DNA多态性变化可作为检测草莓根尖DNA损伤的指标。 相似文献
87.
88.
Spatial dependence and the relationship of soil organic carbon and soil moisture in the Luquillo Experimental Forest,Puerto Rico 总被引:11,自引:0,他引:11
Wang Hongqing Hall Charles A.S. Cornell Joseph D. Hall Myrna H.P. 《Landscape Ecology》2002,17(8):671-684
We used geo-spatial statistical techniques to examine the spatial variation and relationship of soil organic carbon (SOC) and soil moisture (SM) in the Luquillo Experimental Forest (LEF), Puerto Rico, in order to test the hypothesis that mountainous terrain introduces spatial autocorrelation and crosscorrelation in ecosystem and soil properties. Soil samples (n = 100) were collected from the LEF in the summer of 1998 and analyzed for SOC, SM, and bulk density (BD). A global positioning system was used to georeference the location of each sampling site. At each site, elevation, slope and aspect were recorded. We calculated the isotropic and anisotropic semivariograms of soil and topographic properties, as well as the cross-variograms between SOC and SM, and between SOC and elevation. Then we used four models (random, linear, spherical and wave/hole) to test the semi-variances of SOC, SM, BD, elevation, slope and aspect for spatial dependence. Our results indicate that all the studied properties except slope angle exhibit spatial dependence within the scale of sampling (200 – 1000 m sampling interval). The spatially structured variance (the variance due to the location of sampling sites) accounted for a large proportion of the sample variance for elevation (99%), BD (90%), SOC (68%), aspect (56%) and SM (44%). The ranges of spatial dependence (the distances within which parameters are spatially dependent) for aspect, SOC, elevation, SM, and BD were 9810 m, 3070 m, 1120 m, 930 m and 430 m, respectively. Cross correlograms indicate that SOC varies closely with elevation and SM depending on the distances between samples. The correlation can shift from positive to negative as the separation distance increases. Larger ranges of spatial dependence of SOC, aspect and elevation indicate that the distribution of SOC in the LEF is determined by a combination of biotic (e.g., litterfall) and abiotic factors (e.g., microclimate and topographic features) related to elevation and aspect. This demonstrates the importance of both elevation and topographic gradients in controlling climate, vegetation distribution and soil properties as well as the associated biogeochemical processes in the LEF.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
89.
自主创新出成果科技服务出效益 总被引:1,自引:0,他引:1
通过原始创新、集成创新和引进、吸收再创新,四川省农科院在农业“高产、优质、高效、生态、安全”方面取得了丰硕的成果。通过强化科技服务,取得了显著的经济社会效益。最后,总结了主要做法和体会。 相似文献
90.
随着饲料行业国际市场竞争的日趋加剧,我国饲料企业跨境电商业务受到了严重冲击.近几年,由于农业、畜牧业及肉、蛋、奶等产品的市场价格波动,放大了跨境电商活动中原本就存在的跨境物流、金融支付、网络安全、国际法律公约缺失等问题.为在新的竞争环境下有效降低产品市场价格波动对跨境电商造成的不利影响,应从强化国际间贸易协作,拉动国内... 相似文献