植被净初级生产力(net primary productivity, NPP)在全球气候变化及碳循环研究中扮演着重要的角色,精准快速的估算NPP对评估区域生态系统承载力以及合理利用自然资源具有重要的意义。利用2011-2014年甘南地面实测草地地上生物量(aboveg...植被净初级生产力(net primary productivity, NPP)在全球气候变化及碳循环研究中扮演着重要的角色,精准快速的估算NPP对评估区域生态系统承载力以及合理利用自然资源具有重要的意义。利用2011-2014年甘南地面实测草地地上生物量(aboveground biomass, AGB)数据和根冠比系数计算的草地NPP数据,分别验证了MOD17A3 NPP产品和基于CASA(Carnegie-Ames-Stanford approach)模型估算的草地NPP的精度,分析了2000-2016年甘南地区草地NPP的时空动态变化。结果表明:基于CASA模型模拟的草地NPP精度整体上高于MOD17A3 NPP产品的精度,其均方根误差(root mean square error, RMSE)较MOD17A3 NPP小9.94 g C·m^-2;CASA模型分析的甘南地区草地NPP总体上呈现由西南向东北逐渐减少的趋势;对不同草地类型而言,沼泽类的平均NPP最高(469.07 g C·m^-2),温性草原类最低(324.18 g C·m^-2),而占研究区草地总面积比例较大的高寒草甸类和高寒灌丛草甸类草地的平均NPP分别为449.22和465.27 g C·m^-2;2000-2016年间,甘南地区大部分草地NPP稳定不变,其面积占研究区草地总面积的75.31%,NPP呈增加趋势的区域占草地面积的22.63%,而NPP呈减少趋势的区域占比最小,仅为2.06%。以上研究结果表明CASA模型在高寒地区草地NPP评估、草地资源合理利用与管理方面具有重要的应用价值。展开更多
AIM: To investigate whether autologous dendritic cell (DC)-cytokine-induced killer (CIK) cell therapy is able to improve the therapeutic efficacy of chemotherapy in colon cancer.
Thais luteostoma has been utilized as a crude drug whose shell and soft tissue have been widely used for the treatment of heat syndrome in China for thousands of years. The present study was designed to investigate th...Thais luteostoma has been utilized as a crude drug whose shell and soft tissue have been widely used for the treatment of heat syndrome in China for thousands of years. The present study was designed to investigate the antipyretic and anti-inflammatory activities of T. luteostoma. T. luteostoma was divided into shell （TLSH） and soft tissue （TLST） samples in the present study. The rat model of yeast-induced fever was used to investigate their antipyretic effects; and the rat model of hind paw edema induced by carrageenan was utilized to study their anti-inflammatory activities, and at the same time, the concentration variations of the central neurotransmitter [prostaglandin E2 （PGE2） and cyclic adenosine monophosphate （cAMP）], inflammatory mediators [tumor necrosis factor （TNFα）, interleukin-1β （IL-1）, interleukin-2 （IL-2） and interleukin-6 （IL-6）] and ion （Na^＋ and Ca^2＋） were also tested. The results showed that TLSH and TLST extracts significantly inhibited yeast-induced pyrexia in rats （P 〈 0.05）, and exhibited more lasting effects as compared to aspirin, and TLSH had the better antipyretic activity than TLST, and that TLSH and TLST could significantly prevent against carrageenan induced paw edema in rats （P 〈 0.05）; and markedly reduced levels of PGE2, cAMP, TNFα, IL-1β, IL-2, IL-6, and Na^＋/Ca^2＋. In fever model, TLST could significantly reduce the levels of PGE2 （P 〈 0.01） in rats＇ homogenate and TNF a （P 〈 0.05）, IL-113 （P 〈 0.01） in the plasma than TLSH, whereas TLSH could reduce the content of IL-2 （P 〈 0.01） and IL-6 （P 〈 0.01） in plasma and increase the content of Ca2＋ （P 〈 0.01） in plasma and homogenate more significantly than TLST. In conclusion, T. luteostoma extract has antipyretie and anti-inflammatory activities, which may be mediated through the suppression of production of PGE2, cAMP, Na^＋/Ca^2＋ , TNF a, IL-1β, IL-2, and IL-6.展开更多
An extruded Mg-4Zn-0.2Mn-0.2Ca alloy was developed as potential biodegradable bone-plate due to its excellent biocompatibility.Long term in vitro immersion in Hank’s solution and bending test were used to evaluate th...An extruded Mg-4Zn-0.2Mn-0.2Ca alloy was developed as potential biodegradable bone-plate due to its excellent biocompatibility.Long term in vitro immersion in Hank’s solution and bending test were used to evaluate the degradability and the mechanical integrity of the alloy.The results revealed that the degradation rate of the bone-plate increased in the first 7 days and then decreased with the prolonged immersion time before it finally reached a steady stage(about 0.84 mm/a)after immersion for 90 days.The bending strength after immersion for 60 days was 67.6 MPa,indicating that the bone-plate could support certain mechanical load after long term degradation.The formation of corrosion pits after degradation stemmed from the separation of the continuously distributed second phases from Mg matrix under the action of micro-galvanic couples.As a result,the mechanical performance of Mg-4Zn-0.2Mn-0.2Ca alloy was aggravated owing to the corrosion holes on its surface.展开更多
文摘植被净初级生产力(net primary productivity, NPP)在全球气候变化及碳循环研究中扮演着重要的角色,精准快速的估算NPP对评估区域生态系统承载力以及合理利用自然资源具有重要的意义。利用2011-2014年甘南地面实测草地地上生物量(aboveground biomass, AGB)数据和根冠比系数计算的草地NPP数据,分别验证了MOD17A3 NPP产品和基于CASA(Carnegie-Ames-Stanford approach)模型估算的草地NPP的精度,分析了2000-2016年甘南地区草地NPP的时空动态变化。结果表明:基于CASA模型模拟的草地NPP精度整体上高于MOD17A3 NPP产品的精度,其均方根误差(root mean square error, RMSE)较MOD17A3 NPP小9.94 g C·m^-2;CASA模型分析的甘南地区草地NPP总体上呈现由西南向东北逐渐减少的趋势;对不同草地类型而言,沼泽类的平均NPP最高(469.07 g C·m^-2),温性草原类最低(324.18 g C·m^-2),而占研究区草地总面积比例较大的高寒草甸类和高寒灌丛草甸类草地的平均NPP分别为449.22和465.27 g C·m^-2;2000-2016年间,甘南地区大部分草地NPP稳定不变,其面积占研究区草地总面积的75.31%,NPP呈增加趋势的区域占草地面积的22.63%,而NPP呈减少趋势的区域占比最小,仅为2.06%。以上研究结果表明CASA模型在高寒地区草地NPP评估、草地资源合理利用与管理方面具有重要的应用价值。
基金Supported by National Natural Science Foundation of China,No.31171427 and No.30971651 to Wang ZXNational Natural Science Foundation of China,No.30700974 to Cao JXPostdoctoral Foundation of China,No.20060400775 to Cao JX
文摘AIM: To investigate whether autologous dendritic cell (DC)-cytokine-induced killer (CIK) cell therapy is able to improve the therapeutic efficacy of chemotherapy in colon cancer.
基金supported by Marine Industry Research Special Funds for Public Welfare Projects(201205024–1)The Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(ysxk-2010)
文摘Thais luteostoma has been utilized as a crude drug whose shell and soft tissue have been widely used for the treatment of heat syndrome in China for thousands of years. The present study was designed to investigate the antipyretic and anti-inflammatory activities of T. luteostoma. T. luteostoma was divided into shell （TLSH） and soft tissue （TLST） samples in the present study. The rat model of yeast-induced fever was used to investigate their antipyretic effects; and the rat model of hind paw edema induced by carrageenan was utilized to study their anti-inflammatory activities, and at the same time, the concentration variations of the central neurotransmitter [prostaglandin E2 （PGE2） and cyclic adenosine monophosphate （cAMP）], inflammatory mediators [tumor necrosis factor （TNFα）, interleukin-1β （IL-1）, interleukin-2 （IL-2） and interleukin-6 （IL-6）] and ion （Na^＋ and Ca^2＋） were also tested. The results showed that TLSH and TLST extracts significantly inhibited yeast-induced pyrexia in rats （P 〈 0.05）, and exhibited more lasting effects as compared to aspirin, and TLSH had the better antipyretic activity than TLST, and that TLSH and TLST could significantly prevent against carrageenan induced paw edema in rats （P 〈 0.05）; and markedly reduced levels of PGE2, cAMP, TNFα, IL-1β, IL-2, IL-6, and Na^＋/Ca^2＋. In fever model, TLST could significantly reduce the levels of PGE2 （P 〈 0.01） in rats＇ homogenate and TNF a （P 〈 0.05）, IL-113 （P 〈 0.01） in the plasma than TLSH, whereas TLSH could reduce the content of IL-2 （P 〈 0.01） and IL-6 （P 〈 0.01） in plasma and increase the content of Ca2＋ （P 〈 0.01） in plasma and homogenate more significantly than TLST. In conclusion, T. luteostoma extract has antipyretie and anti-inflammatory activities, which may be mediated through the suppression of production of PGE2, cAMP, Na^＋/Ca^2＋ , TNF a, IL-1β, IL-2, and IL-6.
基金Projects(2016YFB0301001,2016YFB0301101)supported by the National Key Research and Development Program of ChinaProject(51801004)supported by the National Natural Science Foundation of China+1 种基金Project(KM201710005005)supported by Beijing Municipal Education Commission,ChinaProjects(2172013,2192006)supported by Beijing Natural Science Foundation,China
文摘An extruded Mg-4Zn-0.2Mn-0.2Ca alloy was developed as potential biodegradable bone-plate due to its excellent biocompatibility.Long term in vitro immersion in Hank’s solution and bending test were used to evaluate the degradability and the mechanical integrity of the alloy.The results revealed that the degradation rate of the bone-plate increased in the first 7 days and then decreased with the prolonged immersion time before it finally reached a steady stage(about 0.84 mm/a)after immersion for 90 days.The bending strength after immersion for 60 days was 67.6 MPa,indicating that the bone-plate could support certain mechanical load after long term degradation.The formation of corrosion pits after degradation stemmed from the separation of the continuously distributed second phases from Mg matrix under the action of micro-galvanic couples.As a result,the mechanical performance of Mg-4Zn-0.2Mn-0.2Ca alloy was aggravated owing to the corrosion holes on its surface.
