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7, 8-dihydroxyflavone (7, 8-DHF), a selective agonist for TrkB receptors, has been well studied for its neurotrophic functions. However, its roles outside the neural tissues have scarcely been studied as yet. In this study, we investigated the protecting roles of 7, 8-DHF in EA.hy926 cells, a human umbilic vein endothelial cell line which was exposed to hydrogen peroxide (H2O2). We found that 7, 8-DHF significantly protected the cells from being damaged by H2O2 through suppression of apoptosis, attenuation of inflammatory factor releasing and inhibition of reactive oxygen species generation. The potent biological effects of 7, 8-DHF were probably executed via its binding to TrkB receptors because the receptor specific antagonist ANA-12 significantly blocked its protecting effects. The protecting roles of 7, 8-DHF in EA.hy926 cells suggest that it will be a promising compound to be developed into a health product that definitely benefits endothelial functions and prevents cardiovascular diseases. 相似文献
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中华鳖幼体呼吸代谢的初步研究 总被引:8,自引:0,他引:8
本文利用改装后的Kalabukhov-Skvorstov呼吸器,同时测定了中华鳖在自由潜水状态下的空气呼吸和水呼吸摄氧量。结果表明:在正常生活状态下,中华鳖主要依靠空气呼吸摄氧;水呼吸仅占总呼吸摄氧量为2.68%左右。呼吸摄氧率无显著昼夜变化。 相似文献
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水产养殖过程中,氮素积累日益严重,而其中亚硝酸盐由于转化速度低,毒性强,对养殖的危害更加突出。对从对虾养殖池中通过反硝化条件选择性富集培养得到的具有去除硝酸盐及亚硝酸盐能力的细菌进行筛选,结果分离到27株能够还原硝酸盐的异养细菌,其中24株在7d内能有效地降低硝酸盐和亚硝酸盐浓度;特别是LZX22、LZX27、LZX23、LZX21等4株使硝酸盐氮由起始的422.25mg/L降至4.00mg/L以下,亚硝酸盐浓度也降至0.40mg/L以下。对这些菌株进行16S rDNA系统发育分析,结果显示:27株菌分属于5个不同的类群,α-Proteobacteria(1),γ-Proteobacteria(10),Actinobacteria(12),Firmicutes(3),和Bacteroides(1);它们在系统发育上分别与11个属相近,分别是Pseudomonas,Halomonas,Acinetobacter,Paracoccus,Arthrobacter,Microbacterium,Cellulosimicrobium,Bacillus,Stenotrophom,和Sphingobacterium。表明所分析的虾池中具有去除硝酸盐和亚硝酸盐能力的细菌具有较高的多样性,特别是多株细菌为首次报道具有去除硝酸盐和亚硝酸盐的能力,为下一步筛选亚硝酸盐高效去除细菌提供了丰富的菌种资源。 相似文献
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Xiaotuan Liu Qingfen Li Qishui Lin Ruyong Sun 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2001,128(4)
Regulation of thermogenic activity and uncoupling protein1 (UCP1) expression in brown adipose tissue (BAT) were studied in euthermic Daurian ground squirrel after acute and chronic cold exposure at 4°C. The UCP1 concentration was indirectly determined by titration with its specific ligand [3H]-labeled GTP, and Ucp1 mRNA was detected by using a [32P]-labeled antisense oligonucleotide probe. Both acute and chronic cold exposure stimulated up-regulation of Ucp1 mRNA. Although UCP1 concentration is not significantly increased after 24 h of cold exposure, it is markedly elevated by 75% in squirrels after 4-week cold adaptation compared with controls raised at 22°C. Changes in T4 5′-deiodinase activity were closely associated with variations of Ucp1 mRNA level. Ucp1 gene expression is significantly affected by cold exposure in BAT from euthermic Daurian ground squirrels. In addition, the activation of T4 5′-deiodinase may be an important regulatory factor in cold-induced Ucp1 expression. 相似文献
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Fuhua Zhang Yishuang Yu Jiaming Yu Shibao Wu Shaoshan Li Qiaoyun Wang Yue Min Ruyong Sun 《Zoo biology》2020,39(2):65-72
Understanding reproductive behavior is important for the conservation of endangered species, but research on the reproductive behavior of Sunda pangolins (Manis javanica Desmarest, 1822) is still very scarce. In this study, we used focal animal sampling and all-occurrence recording by an infrared monitor to observe the behaviors of two Sunda pangolins during a 5-day breeding period at the Pangolin Research Base for Artificial Rescue and Conservation Breeding of South China Normal University (PRB-SCNU). The behavioral characteristics and breeding strategies were analyzed, and the results were discussed together with information on other captive Sunda pangolin pairs at PRB-SCNU. The results found that there was no obvious estrus behavior in the captive female, while the male could exhibit sexual excitement and courtship behavior after a brief introduction period. Repeated copulation continued over many days after the female accepted the courtship. The average duration of copulatory behavior was 248.9 ± 148.7 s (n = 25), and all copulation occurred between 20:00 and 08:00 hr in the natural day–night photoperiod. The mating position of Sunda pangolins was lateral–ventral and was classified as the ninth or eleventh pattern under both Dewsbury's and Dixson's classification systems. This study can provide scientific guidance for the captive breeding and management of Sunda pangolins and other pangolin species, which is of great significance for ex situ conservation tactics. 相似文献
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鲇鱼的静止代谢率及其与体重,温度和性别的关系 总被引:15,自引:3,他引:12
采用连续流水式呼吸仪测定了127尾鲇鱼(体重22.6-452.4g)的静止代谢率。在10,15,20,25和30℃水温下,鲇鱼平均特定体重代谢率分别为22.99,58.55,79.20,109.29和123.89mgO2/kg/h。体重(W)与静止代谢率(Ms)回归关系(Ms=aW^b)的体重指数b随温度上升而下降,温度(T)与特定体重代谢率(M')回归关系(M'=AT^B)的温度指数B随体重增加 相似文献
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布氏田鼠数量和空间分布的年际动态及周期性初步分析 总被引:5,自引:1,他引:5
布氏田鼠的分布特点是避开山丘,季节河河床和芨芨草滩;主要分布在季节河两侧,分布区缩小时,向季节河两侧收缩,布氏田鼠年动态是否有周期性尚难以下最后的结论,但存在季节动态是可以肯定的,布氏田鼠在其地理分布中心区和边缘区的种群年际动态可能存在差异,中心区的种群动态相对可能稳定些,边缘区的种群波动可能大些。 相似文献
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高原鼠兔蒸发失水的地位及热能调节 总被引:9,自引:4,他引:5
本文对高原鼠兔(Ochotona curzoniae)的静止代谢率(RMR)、蒸发失水(EWL)、非颤抖性产热(NST)等能学参数进行了测定,计算了干燥热传导(dry C)、热能调节热标(TI)等,评估了蒸发散热(EHL)在热传导(C)中的地位,结果表明:高原鼠兔的基础代谢率(BMR)和最小热传导(C_m)均高于期望值;25℃以上EHL占有重要地位;热能调节能力较好,但抗高温能力较差;这些特征对于栖居在年气温差较小、日温差大的高寒环境中的高原鼠兔具重要的适应意义。 相似文献