不同植被恢复措施下剖面根系与SOC的分布特征

根系是影响水土流失和土壤有机碳（SOC）变化的重要因素。在水土流失区,研究不同植被恢复措施下,根系生物量和土壤有机碳的分布特征对了解区域土壤碳循环具有重要意义。在水土流失严重的黄土丘陵沟壑区的燕沟小流域,选择地形条件类似的梁峁坡,采集了10种不同植被治理恢复措施下的剖面（0—100cm）根系和土壤样品,研究了根系生物量和SOC在剖面的分布特征。结果显示：不同治理措施下的SOC呈现出灌木〉乔木〉灌草〉草本的趋势,而根系生物量呈现出乔木〉灌木〉灌草〉草本的趋势;SOC和细根生物量都随土层深度的增加呈对数递减趋势,但同一土层SOC和细根生物量的分布不一致,且根系比SOC的分布浅。

THE ROLE OF Th17 CELLS AND Th17-RELATED FACTORS IN CHRONIC HEPATITIS B

Objective To study the relationship between the Th17 cells and Th17 related factors and chronic hepatitis B virus infection. Methods This study consisted of 78 patients with chronic hepatitis B and 23 healthy subjects. The patients were divided into mild, moderate and severe group according to their condition. The serum levels of IL-17, IL-23, IL-1β, IL-6 and liver damage index were measured and analyzed. Results The levels of IL-17, IL-23, IL-1β, and IL-6 in the patients were higher than that in the healthy subjects （F=23.52 219.44,q=10.77--36.18,P〈0.05）. As compared among the patients between moderate and mild group, only IL-6 level was higher in the moderate group. The levels of IL-17, IL-23, IL-1β, and IL-6 in the severe group were higher than that in both mild and moderate groups, the differences being significant （q=6.40--16.80, P d0.05）. The level of IL-17 in the patients was positively correlated with ALT （r=0.801 ,P〈0.05）, not correlated with HBV DNA and negatively cor- related with ALB and A/G （r=-0.512,-0.547;P〈0.05）. Conclusion Th17 cells involve in the occurrence and development of inflammation process of the liver of patients with chronic hepatitis B.