目的探讨妊娠期女性收缩压轨迹的变化模式与新生儿胎龄体重的关系。方法采用回顾性队列研究,收集江苏省昆山地区2013-2017年进行产检建卡(孕8~14周)并单胎分娩的63724名孕妇及其新生儿的资料,主要包括孕妇一般人口学特征、疾病史、妊娠...目的探讨妊娠期女性收缩压轨迹的变化模式与新生儿胎龄体重的关系。方法采用回顾性队列研究,收集江苏省昆山地区2013-2017年进行产检建卡(孕8~14周)并单胎分娩的63724名孕妇及其新生儿的资料,主要包括孕妇一般人口学特征、疾病史、妊娠期血压监测记录、分娩信息,新生儿出生性别、体重等。通过SAS软件Proc Traj程序将孕妇妊娠期收缩压变化轨迹模式分为四类,即低-稳定轨迹型、正常-稳定轨迹型、高-正常轨迹型、正常-高轨迹型,并根据分娩周数、性别及出生体重将新生儿出生体重分为小于胎龄儿(smaller for gestional age, SGA)、适于胎龄儿(appropriate for gestional age, AGA)及大于胎龄儿(larger for gestional age, LGA)。采用无序多分类logistic回归模型分析孕妇不同的血压轨迹变化模式与SGA及LGA的关联性。结果低-稳定型、正常-稳定型、高-正常型、正常-高型中SGA发生率分别为8.39%、8.37%、11.79%、16.12%,四组间的差异具有统计学意义;而四种不同血压轨迹组LGA发生率分别为10.09%、11.63%、13.10%、11.81%,四组间差异亦有统计学意义。调整混杂因素后,在多因素logistic回归分析中,与低—稳定型相比,正常-稳定型,高-正常型,正常-高型发生SGA的风险增加,其OR值(95%CI)分别为1.19(1.13~1.25)、1.52(1.02~2.32)、2.21(1.80~2.51),而不同的血压轨迹模式与LGA的关联性未发现有统计学意义。结论无论是妊娠早期高SBP还是妊娠期SBP过度升高均增加SGA发生的风险。展开更多
The valence electronic structures of tantalum carbide (TaC) and tantalum nitride (TaN) are studied by using the empirical electronic theory (EET). The results reveal that the bonds of these compounds have covalent,met...The valence electronic structures of tantalum carbide (TaC) and tantalum nitride (TaN) are studied by using the empirical electronic theory (EET). The results reveal that the bonds of these compounds have covalent,metallic and ionic characters. For a quantitative analysis of the relative strength of these components,their ionicities have been calculated by implanting the results of EET to the PVL model. It has been found that the ionicity of tantalum carbide is smaller than that of tantalum nitride. The EET results also reveal that the covalent electronic number of the strongest bond in the former is larger than that of the latter. All these suggest that the covalent bond of TaC is stronger than that of TaN,which coincides to that de-duced from the first-principles method.展开更多
文摘目的探讨妊娠期女性收缩压轨迹的变化模式与新生儿胎龄体重的关系。方法采用回顾性队列研究,收集江苏省昆山地区2013-2017年进行产检建卡(孕8~14周)并单胎分娩的63724名孕妇及其新生儿的资料,主要包括孕妇一般人口学特征、疾病史、妊娠期血压监测记录、分娩信息,新生儿出生性别、体重等。通过SAS软件Proc Traj程序将孕妇妊娠期收缩压变化轨迹模式分为四类,即低-稳定轨迹型、正常-稳定轨迹型、高-正常轨迹型、正常-高轨迹型,并根据分娩周数、性别及出生体重将新生儿出生体重分为小于胎龄儿(smaller for gestional age, SGA)、适于胎龄儿(appropriate for gestional age, AGA)及大于胎龄儿(larger for gestional age, LGA)。采用无序多分类logistic回归模型分析孕妇不同的血压轨迹变化模式与SGA及LGA的关联性。结果低-稳定型、正常-稳定型、高-正常型、正常-高型中SGA发生率分别为8.39%、8.37%、11.79%、16.12%,四组间的差异具有统计学意义;而四种不同血压轨迹组LGA发生率分别为10.09%、11.63%、13.10%、11.81%,四组间差异亦有统计学意义。调整混杂因素后,在多因素logistic回归分析中,与低—稳定型相比,正常-稳定型,高-正常型,正常-高型发生SGA的风险增加,其OR值(95%CI)分别为1.19(1.13~1.25)、1.52(1.02~2.32)、2.21(1.80~2.51),而不同的血压轨迹模式与LGA的关联性未发现有统计学意义。结论无论是妊娠早期高SBP还是妊娠期SBP过度升高均增加SGA发生的风险。
基金Supported by the National Natural Science Foundation of China (Grant No. 10702060)the Ministry of Science and Technology of China (2005CB724400 and 2005CB724404)
文摘The valence electronic structures of tantalum carbide (TaC) and tantalum nitride (TaN) are studied by using the empirical electronic theory (EET). The results reveal that the bonds of these compounds have covalent,metallic and ionic characters. For a quantitative analysis of the relative strength of these components,their ionicities have been calculated by implanting the results of EET to the PVL model. It has been found that the ionicity of tantalum carbide is smaller than that of tantalum nitride. The EET results also reveal that the covalent electronic number of the strongest bond in the former is larger than that of the latter. All these suggest that the covalent bond of TaC is stronger than that of TaN,which coincides to that de-duced from the first-principles method.
