目的:探讨老年患者胃液中TNF-α,CA19-9和CEA联合检测对胃癌的诊断价值．方法:采用放射免疫技术测定42例胃癌和61例良性胃病老年患者胃液中TNF-α,CA19-9和CEA浓度．结果:胃癌组胃液中TNF-α,CA19-9和CEA的浓度显著高于良性胃病组(8．96...目的:探讨老年患者胃液中TNF-α,CA19-9和CEA联合检测对胃癌的诊断价值．方法:采用放射免疫技术测定42例胃癌和61例良性胃病老年患者胃液中TNF-α,CA19-9和CEA浓度．结果:胃癌组胃液中TNF-α,CA19-9和CEA的浓度显著高于良性胃病组(8．96±2．10 mg／L vs 4．92±1．24．5．66±1．25 mg／L;59．47±10．58 IU／L vs 36．89±11．23．38．73±9．23 IU／L; 31．68±5．58 mg／L vs 1'．55±3．82,19.42±5．19 mg／L,均P<0．001);胃癌组联合检测胃液中TNF-α,CA19-9和CEA,其敏感度和特异度分别97．4％,89．3％,均明显高于单项指标的敏感度和特异度．结论:联合检测胃液中TNF-α,CA19-9和CEA能有助于提高胃癌的诊断．展开更多
The phase transition of tungsten(W)under high pressures was investigated with molecular dynamics simulation.The structure was characterized in terms of the pair distribution function and the largest standard cluster a...The phase transition of tungsten(W)under high pressures was investigated with molecular dynamics simulation.The structure was characterized in terms of the pair distribution function and the largest standard cluster analysis(LSCA).It is found that under 40−100 GPa at a cooling rate of 0.1 K/ps a pure W melt first crystallizes into the body-centred cubic(BCC)crystal,and then transfers into the hexagonal close-packed(HCP)crystal through a series of BCC−HCP coexisting states.The dynamic factors may induce intermediate stages during the liquid−solid transition and the criss-cross grain boundaries cause lots of indistinguishable intermediate states,making the first-order BCC−HCP transition appear to be continuous.Furthermore,LSCA is shown to be a parameter-free method that can effectively analyze both ordered and disordered structures.Therefore,LSCA can detect more details about the evolution of the structure in such structure transition processes with rich intermediate structures.展开更多
Dynamic characteristics of UV enhanced gas–solid PVC chlorination process were revealed by a UV–Vis spectral online analysis method. Experimental results showed an instantaneous increase of the chlorination rate as ...Dynamic characteristics of UV enhanced gas–solid PVC chlorination process were revealed by a UV–Vis spectral online analysis method. Experimental results showed an instantaneous increase of the chlorination rate as soon as UV light was affiliated, which demonstrated the intensified effect of UV radiation on PVC chlorination directly.Different affiliation methods of UV light were then studied, proving that continuous UV radiation could enhance the chlorination process significantly while intermittent UV radiation was able to initiate the chlorination reaction once it was conducted. Besides, experiments were carried out to study the influences of parameters on the chlorination process such as UV wavelength, chlorination temperature, partial pressure of chlorine gas and PVC raw materials. Among all the parameters, chlorination temperature and partial pressure of chlorine gas were testified as two key factors to determine the chlorination performance. Thermal analysis of CPVC products showed that their corresponding properties such as the glass transition temperature(Tg) and the homogeneity of chlorine distribution in polymer phase were improved with the increase of chlorine content.展开更多
We report the discovery and characterization of a novel 112-type iron pnictide EuFeAs2, with La-doping induced superconductivity in a series of Eu1- xLaxFeAs2. The polycrystalline samples were synthesized through soli...We report the discovery and characterization of a novel 112-type iron pnictide EuFeAs2, with La-doping induced superconductivity in a series of Eu1- xLaxFeAs2. The polycrystalline samples were synthesized through solid state reaction method only within a very narrow temperature window around 1073 K. Small single crystals were also grown from a flux method with the size about 100μm. The crystal structure was identified by single crystal X-ray diffraction analysis as a monoclinic structure with space group of P2 1/m. From resistivity and magnetic susceptibility measurements, we found that the parent compound EuFeAs2 shows distinct anomalies probably due to the Fe2＋ related antiferromagnetic/structural phase transition near 110K and the Eu2＋ related antiferromagnetic phase transition near 40K. La-doping suppressed both phase transitions to lower temperatures and induced superconducting transitions with a Tc - 11 K for Eu0.85La0.15FeAs2.展开更多
文摘目的:探讨老年患者胃液中TNF-α,CA19-9和CEA联合检测对胃癌的诊断价值．方法:采用放射免疫技术测定42例胃癌和61例良性胃病老年患者胃液中TNF-α,CA19-9和CEA浓度．结果:胃癌组胃液中TNF-α,CA19-9和CEA的浓度显著高于良性胃病组(8．96±2．10 mg／L vs 4．92±1．24．5．66±1．25 mg／L;59．47±10．58 IU／L vs 36．89±11．23．38．73±9．23 IU／L; 31．68±5．58 mg／L vs 1'．55±3．82,19.42±5．19 mg／L,均P<0．001);胃癌组联合检测胃液中TNF-α,CA19-9和CEA,其敏感度和特异度分别97．4％,89．3％,均明显高于单项指标的敏感度和特异度．结论:联合检测胃液中TNF-α,CA19-9和CEA能有助于提高胃癌的诊断．
基金Projects(51661005,U1612442)supported by the National Natural Science Foundation of ChinaProject(QKHJC[2017]1025)supported by the Natural Science Foundation of Guizhou Province,ChinaProject(2018JJ3560)supported by the Natural Science Foundation of Hunan Province,China。
文摘The phase transition of tungsten(W)under high pressures was investigated with molecular dynamics simulation.The structure was characterized in terms of the pair distribution function and the largest standard cluster analysis(LSCA).It is found that under 40−100 GPa at a cooling rate of 0.1 K/ps a pure W melt first crystallizes into the body-centred cubic(BCC)crystal,and then transfers into the hexagonal close-packed(HCP)crystal through a series of BCC−HCP coexisting states.The dynamic factors may induce intermediate stages during the liquid−solid transition and the criss-cross grain boundaries cause lots of indistinguishable intermediate states,making the first-order BCC−HCP transition appear to be continuous.Furthermore,LSCA is shown to be a parameter-free method that can effectively analyze both ordered and disordered structures.Therefore,LSCA can detect more details about the evolution of the structure in such structure transition processes with rich intermediate structures.
基金Supported by the National Science and Technology Key Supporting Project(2013BAF08B05)the National Natural Science Foundation of China(21176137)
文摘Dynamic characteristics of UV enhanced gas–solid PVC chlorination process were revealed by a UV–Vis spectral online analysis method. Experimental results showed an instantaneous increase of the chlorination rate as soon as UV light was affiliated, which demonstrated the intensified effect of UV radiation on PVC chlorination directly.Different affiliation methods of UV light were then studied, proving that continuous UV radiation could enhance the chlorination process significantly while intermittent UV radiation was able to initiate the chlorination reaction once it was conducted. Besides, experiments were carried out to study the influences of parameters on the chlorination process such as UV wavelength, chlorination temperature, partial pressure of chlorine gas and PVC raw materials. Among all the parameters, chlorination temperature and partial pressure of chlorine gas were testified as two key factors to determine the chlorination performance. Thermal analysis of CPVC products showed that their corresponding properties such as the glass transition temperature(Tg) and the homogeneity of chlorine distribution in polymer phase were improved with the increase of chlorine content.
基金the financial supports from the National Natural Science Foundation of China (11474339)the National Basic Research Program of China (973 Program, 2016YFA0300301, 2010CB923000 and 2011CBA00100)the Youth Innovation Promotion Association of the Chinese Academy of Sciences
文摘We report the discovery and characterization of a novel 112-type iron pnictide EuFeAs2, with La-doping induced superconductivity in a series of Eu1- xLaxFeAs2. The polycrystalline samples were synthesized through solid state reaction method only within a very narrow temperature window around 1073 K. Small single crystals were also grown from a flux method with the size about 100μm. The crystal structure was identified by single crystal X-ray diffraction analysis as a monoclinic structure with space group of P2 1/m. From resistivity and magnetic susceptibility measurements, we found that the parent compound EuFeAs2 shows distinct anomalies probably due to the Fe2＋ related antiferromagnetic/structural phase transition near 110K and the Eu2＋ related antiferromagnetic phase transition near 40K. La-doping suppressed both phase transitions to lower temperatures and induced superconducting transitions with a Tc - 11 K for Eu0.85La0.15FeAs2.
