To evaluate the feasibility and clinical significance of the PCR SSP technique in detecting K ras gene mutation at codon 12 in pancreatic adenocarcinoma tissues. 80 specimens of surgical resection or biopsy samples ...To evaluate the feasibility and clinical significance of the PCR SSP technique in detecting K ras gene mutation at codon 12 in pancreatic adenocarcinoma tissues. 80 specimens of surgical resection or biopsy samples were tested at our hospital from January 1994 to September 1995. Three different special sequence primers (SSP) synthesized according to mutation styles of CGT, GTT, GAT were respectively prepared. Three amplification reactions were performed for each sample. The amplification products were analyzed by conventional polyacrylamide gel electrophoresis, stained with ethidium bromide and observed under UV transillumination. Results: All of the 34 pancreatic adenocarcinoma samples had positive PCR results with the mutation rate 100%. 7 cases were CGT mutation, 18 GGT and 17 GAT mutation, in which 2 types of mutation existed in 8 cases. No mutation appeared in 13 normal pancreatic tissues, 6 insulinomas, 6 chronic pancreatitis, 5 benign pancreatic cysts, 7 bile duct carcinoma, 5 ampulla carcinoma and 4 carcinomas of duodenal papilla. Conclusion: Pancreatic adenocarcinoma is one of the commonly encounted tumors and is still very difficult to diagnose at the early stage and to distinguish from other lesions preoperatively. Our study indicates that PCR SSP is an ideal assay in comparison with other methods to detect K ras gene mutation. It is simple, rapid, specific, sensitive and easily generalized for clinical application on preoperative diagnosis.展开更多
人类活动和气候影响土地利用变化,而土地利用变化是影响生境质量变化最基本因素之一,探究不同气候情景下生境质量对区域土地资源可持续利用和生态保护具有重要意义。本文以南昌市为例,基于耦合SD(System dynamics)-PLUS(Patch-generatin...人类活动和气候影响土地利用变化,而土地利用变化是影响生境质量变化最基本因素之一,探究不同气候情景下生境质量对区域土地资源可持续利用和生态保护具有重要意义。本文以南昌市为例,基于耦合SD(System dynamics)-PLUS(Patch-generating land use simulation)模型模拟预测共享社会经济发展路径(Shared socioeconomic pathways, SSPs)与典型浓度路径(Representative concentration pathways, RCPs)组合情景下南昌市2035年土地利用格局,InVEST (Integrated valuation of ecosystem services and trade-offs)模型评估2000—2020年以及3种不同气候情景下南昌市2035年生境质量并进行时空变化分析,结果表明:3种情景下,2035年南昌市耕地、林地、草地面积下降,建设用地扩张迅速,水域和未利用地变化幅度较小。2000—2020年生境质量持续下降且空间分布差异较大,优等生境质量分布于山地丘陵以及湖泊水域,中、差等则分布于耕作区和城镇地区。3种气候情景下,2035年南昌市生境质量呈减速下降趋势,主要表现出中等向差等生境转换,退化程度由大到小依次为SSP585、SSP245、SSP119。研究结果可为南昌市高质量发展和生物多样性保护提供科学依据。展开更多
Within the context of our current research and understanding of climate change,decisionmakers are particularly concerned with the extent of future climate change,its comprehensive impact,and the types of socioeconomic...Within the context of our current research and understanding of climate change,decisionmakers are particularly concerned with the extent of future climate change,its comprehensive impact,and the types of socioeconomic pathways available with respect to mitigation and adaptation.Among the factors contributing to these important issues,the role of air pollution in global and regional climate warming remains as one of the largest uncertainties.On the basis of understanding of the IPCC Fifth Assessment Report,specifically,in the role of air pollution in climate change,scenarios establishment,and relationship between the Shared Socioeconomic Pathways(SSPs) and Representative Concentration Pathways(RCPs).Weaknesses and reflections were discussed here especially in strengthening impact,adaptation and mitigation research that related with changes in air pollution and climate.In the future,there are needs to in-depth understand how and why the air pollution in China is so serious and changing; to understand the likely future changes in air pollution and climate; to strengthen comprehensive impact research and selective reduction strategies related to changes in air pollution and climate.Furthermore,this study outlines the needs to develop strategies to close the loop of differential impacts and costs; to establish co-benefits and sustainable development goals,to identify the crucial risks and options for synergies/trade-offs; to integrate sector-specific details with macro-economics,and to integrate the assessments of the various policy instruments.All these focus areas will help to facilitate the transition of economic development patterns towards green and low-carbon development.展开更多
This study measures regional impacts of adaptation to climate change for the Paris Agreement under the Shared Socio-Economic Pathways and Representative Concentration Pathways scenarios. We develop a global economic m...This study measures regional impacts of adaptation to climate change for the Paris Agreement under the Shared Socio-Economic Pathways and Representative Concentration Pathways scenarios. We develop a global economic model with adaptation to climate change. Simulated results indicate that: 1) Asian and African adaptation costs exceed more than one percent of GDP in the year 2100 under the business as usual scenario;2) adaptation costs under the 2.0°C target are higher in Asia and Africa than other regions;and 3) adaptation costs amount to one percent of GDP in Japan, EU and Latin America under the 1.5°C target scenario by adaptation.展开更多
Under the conditions of climate warming,grassland degradation,frequent sandstorms,and fast increases in livestock numbers,coordinating animal husbandry and ecological protection is an important issue facing Mongolia....Under the conditions of climate warming,grassland degradation,frequent sandstorms,and fast increases in livestock numbers,coordinating animal husbandry and ecological protection is an important issue facing Mongolia.Using Khutag-Undur as an example,this study explores the dynamic process,future scenarios,and optimization strategies of the animal husbandry system in a typical Soum of Mongolia from 2015 to 2050 under three future climate socioeconomic scenarios of CMIP 6:SSP1-RCP2.6,SSP2-RCP4.5,and SSP5-RCP8.5.First,the animal husbandry system was deconstructed into three subsystems:grassland primary production,livestock secondary production,and herder consumption.Based on the negative feedback mechanism of forage-livestock balance,a system dynamics model for the Khutag-Undur Soum animal husbandry system was developed.This model integrates spatial data such as land cover and NPP,as well as statistical data on livestock,herder income and expenditures,sample plot surveys,and herder questionnaires.The model was used to simulate the historical changes(2015-2022)in forage production and carrying capacity,livestock stock,and livestock output of Khutag-Undur,and then to forecast the future scenarios of those variables for 2022-2050.Second,the most suitable future scenario for the Soum was identified by comparing the three future scenarios using a pastural system sustainability evaluation method.Finally,based on three indicators of livestock numbers,a two-step livestock reduction strategy was proposed.The main conclusions are that the rapid growth of livestock numbers in Khutag-Undur places considerable pressure on the grassland,and the SSP1-RCP2.6 scenario is the most suitable future scenario for the Soum.However,even in this suitable scenario,grassland overloading remains evident.The continuous implementation of a livestock reduction strategy is recommended to maintain the sustainable development of animal husbandry and grassland conservation.展开更多
文摘To evaluate the feasibility and clinical significance of the PCR SSP technique in detecting K ras gene mutation at codon 12 in pancreatic adenocarcinoma tissues. 80 specimens of surgical resection or biopsy samples were tested at our hospital from January 1994 to September 1995. Three different special sequence primers (SSP) synthesized according to mutation styles of CGT, GTT, GAT were respectively prepared. Three amplification reactions were performed for each sample. The amplification products were analyzed by conventional polyacrylamide gel electrophoresis, stained with ethidium bromide and observed under UV transillumination. Results: All of the 34 pancreatic adenocarcinoma samples had positive PCR results with the mutation rate 100%. 7 cases were CGT mutation, 18 GGT and 17 GAT mutation, in which 2 types of mutation existed in 8 cases. No mutation appeared in 13 normal pancreatic tissues, 6 insulinomas, 6 chronic pancreatitis, 5 benign pancreatic cysts, 7 bile duct carcinoma, 5 ampulla carcinoma and 4 carcinomas of duodenal papilla. Conclusion: Pancreatic adenocarcinoma is one of the commonly encounted tumors and is still very difficult to diagnose at the early stage and to distinguish from other lesions preoperatively. Our study indicates that PCR SSP is an ideal assay in comparison with other methods to detect K ras gene mutation. It is simple, rapid, specific, sensitive and easily generalized for clinical application on preoperative diagnosis.
文摘人类活动和气候影响土地利用变化,而土地利用变化是影响生境质量变化最基本因素之一,探究不同气候情景下生境质量对区域土地资源可持续利用和生态保护具有重要意义。本文以南昌市为例,基于耦合SD(System dynamics)-PLUS(Patch-generating land use simulation)模型模拟预测共享社会经济发展路径(Shared socioeconomic pathways, SSPs)与典型浓度路径(Representative concentration pathways, RCPs)组合情景下南昌市2035年土地利用格局,InVEST (Integrated valuation of ecosystem services and trade-offs)模型评估2000—2020年以及3种不同气候情景下南昌市2035年生境质量并进行时空变化分析,结果表明:3种情景下,2035年南昌市耕地、林地、草地面积下降,建设用地扩张迅速,水域和未利用地变化幅度较小。2000—2020年生境质量持续下降且空间分布差异较大,优等生境质量分布于山地丘陵以及湖泊水域,中、差等则分布于耕作区和城镇地区。3种气候情景下,2035年南昌市生境质量呈减速下降趋势,主要表现出中等向差等生境转换,退化程度由大到小依次为SSP585、SSP245、SSP119。研究结果可为南昌市高质量发展和生物多样性保护提供科学依据。
基金supported by grants from National Key Project of Basic Research (2011CB403401)
文摘Within the context of our current research and understanding of climate change,decisionmakers are particularly concerned with the extent of future climate change,its comprehensive impact,and the types of socioeconomic pathways available with respect to mitigation and adaptation.Among the factors contributing to these important issues,the role of air pollution in global and regional climate warming remains as one of the largest uncertainties.On the basis of understanding of the IPCC Fifth Assessment Report,specifically,in the role of air pollution in climate change,scenarios establishment,and relationship between the Shared Socioeconomic Pathways(SSPs) and Representative Concentration Pathways(RCPs).Weaknesses and reflections were discussed here especially in strengthening impact,adaptation and mitigation research that related with changes in air pollution and climate.In the future,there are needs to in-depth understand how and why the air pollution in China is so serious and changing; to understand the likely future changes in air pollution and climate; to strengthen comprehensive impact research and selective reduction strategies related to changes in air pollution and climate.Furthermore,this study outlines the needs to develop strategies to close the loop of differential impacts and costs; to establish co-benefits and sustainable development goals,to identify the crucial risks and options for synergies/trade-offs; to integrate sector-specific details with macro-economics,and to integrate the assessments of the various policy instruments.All these focus areas will help to facilitate the transition of economic development patterns towards green and low-carbon development.
文摘This study measures regional impacts of adaptation to climate change for the Paris Agreement under the Shared Socio-Economic Pathways and Representative Concentration Pathways scenarios. We develop a global economic model with adaptation to climate change. Simulated results indicate that: 1) Asian and African adaptation costs exceed more than one percent of GDP in the year 2100 under the business as usual scenario;2) adaptation costs under the 2.0°C target are higher in Asia and Africa than other regions;and 3) adaptation costs amount to one percent of GDP in Japan, EU and Latin America under the 1.5°C target scenario by adaptation.
基金The National Key R&D Program of China(2022YFE0119200)The National Natural Science Foundation of China(32161143025,42371283)The Second Tibetan Plateau Scientific Expedition and Research Program(STEP),China(2019QZKK0603)。
文摘Under the conditions of climate warming,grassland degradation,frequent sandstorms,and fast increases in livestock numbers,coordinating animal husbandry and ecological protection is an important issue facing Mongolia.Using Khutag-Undur as an example,this study explores the dynamic process,future scenarios,and optimization strategies of the animal husbandry system in a typical Soum of Mongolia from 2015 to 2050 under three future climate socioeconomic scenarios of CMIP 6:SSP1-RCP2.6,SSP2-RCP4.5,and SSP5-RCP8.5.First,the animal husbandry system was deconstructed into three subsystems:grassland primary production,livestock secondary production,and herder consumption.Based on the negative feedback mechanism of forage-livestock balance,a system dynamics model for the Khutag-Undur Soum animal husbandry system was developed.This model integrates spatial data such as land cover and NPP,as well as statistical data on livestock,herder income and expenditures,sample plot surveys,and herder questionnaires.The model was used to simulate the historical changes(2015-2022)in forage production and carrying capacity,livestock stock,and livestock output of Khutag-Undur,and then to forecast the future scenarios of those variables for 2022-2050.Second,the most suitable future scenario for the Soum was identified by comparing the three future scenarios using a pastural system sustainability evaluation method.Finally,based on three indicators of livestock numbers,a two-step livestock reduction strategy was proposed.The main conclusions are that the rapid growth of livestock numbers in Khutag-Undur places considerable pressure on the grassland,and the SSP1-RCP2.6 scenario is the most suitable future scenario for the Soum.However,even in this suitable scenario,grassland overloading remains evident.The continuous implementation of a livestock reduction strategy is recommended to maintain the sustainable development of animal husbandry and grassland conservation.
