目的探讨原发性高血压(EH)患者血清转化生长因子β1(TGF-β1)水平对血压变异性(BPV)及昼夜节律的影响。方法将2016年8月至2018年10月收治的118例EH患者纳入观察组,同时,将同期体检的120例健康人群纳入对照组;对比2组血清TGFβ-1水平,血...目的探讨原发性高血压(EH)患者血清转化生长因子β1(TGF-β1)水平对血压变异性(BPV)及昼夜节律的影响。方法将2016年8月至2018年10月收治的118例EH患者纳入观察组,同时,将同期体检的120例健康人群纳入对照组;对比2组血清TGFβ-1水平,血压BPV及血压昼夜节律。结果观察组血清TGF-β1明显高于对照组(P<0.05)。观察组24 h SBP、dSBP、nSBP、mSBP均明显高于对照组,而其24 h DBP、dDBP、nDBP、mDBP均明显低于对照组(P<0.05)。观察组24 h SBPV、24 h DBPV、nDBPV、mSBPV与对照组相比差异有统计学意义(P<0.05)。观察组不同水平血清TGF-β1 BPV差异有统计学意义(P<0.05);且观察组血清TGF-β1与24 h SBPV、mSBPV呈正相关(r=0.541,0.5552;P均<0.05),而与24 h DBPV、nDBPV呈负相关(r=-0.477,-0.468;P均<0.05)。观察组发生昼夜节律异常率为95.76%,对照组发生昼夜节律异常率为56.67%,差异有统计学意义(P<0.05)。结论EH患者血清TGF-β1水平明显较高,BPV在一定范围高于正常人群,昼夜节律异常率较高,且其血清TGF-β1水平与BPV具有相关性。展开更多
In this study, we prepared PLLA/bpV（pic） microspheres, a bpV（pic） controlled release system and examined their ability to protect nerve cells and promote axonal growth. PLLA microspheres were prepared by employing...In this study, we prepared PLLA/bpV（pic） microspheres, a bpV（pic） controlled release system and examined their ability to protect nerve cells and promote axonal growth. PLLA microspheres were prepared by employing the o/w single emulsification-evaporation technique. Neural stem cells and dorsal root ganglia were divided into 3 groups in terms of the treatment they received： a routine medium group（cultured in DMEM）, a PLLA microsphere group（DMEM containing PLLA microspheres alone） and a PLLA/bpV（pic） group [DMEM containing PLLA/bpV（pic） microspheres]. The effects of PLLA/bpV（pic） microspheres were evaluated by the live-dead test and measurement of axonal length. Our results showed that PLLA/bpV（pic） granulation rate was（88.2±5.6）%; particle size was（16.8±3.1）%, drug loading was（4.05±0.3）%; encapsulation efficiency was（48.5±1.8）%. The release time lasted for 30 days. In PLLA/bpV（pic） microsphere group, the cell survival rate was（95.2 ±4.77）%, and the length of dorsal root ganglion（DRG） was 718±95 μm, which were all significantly greater than those in ordinary routine medium group and PLLA microsphere group. This preliminary test results showed the PLLA/bpV（pic） microspheres were successfully prepared and they could promote the survival and growth of neural cells in DRG.展开更多
In this paper, fatigue verification of Class 1 nuclear power piping according to ASME Boiler ＆ Pressure Vessel Code, Section III, NB-3600, is addressed. Basic design requirements and relevant verification procedures ...In this paper, fatigue verification of Class 1 nuclear power piping according to ASME Boiler ＆ Pressure Vessel Code, Section III, NB-3600, is addressed. Basic design requirements and relevant verification procedures using Design-By-Analysis are first reviewed in detail. Thereafter, a so-called simplified elastic-plastic discontinuity analysis for further verification when the basic requirements found unsatisfactory is examined and discussed. In addition, necessary computational procedures for evaluating alternating stress intensities and cumulative damage factors are studied in detail. The authors＇ emphasis is placed on alternative verification procedures, which do not violate the general design principles upon which the code is built, for further verification if unsatisfactory results are found in the simplified elastic-plastic analysis. An alternative which employs a non-linear finite element computation and a refined numerical approach for re-evaluating the cumulative damage factors is suggested. Using this alternative, unavoidable plastic strains can be correctly taken into account in a computationally affordable way, and the reliability of the verification will not be affected by uncertainties introduced in the simplified elastic-plastic analysis through the penalty factor Ke and other simplifications.展开更多
Fatigue verification of Class 1 nuclear power piping according to ASME Boiler and Pressure Vessel Code, Section III, NB-3600, which is often discussed in connection to power uprate and life-extension of aging reactors...Fatigue verification of Class 1 nuclear power piping according to ASME Boiler and Pressure Vessel Code, Section III, NB-3600, which is often discussed in connection to power uprate and life-extension of aging reactors in recent years, is dealt with. Key parameters involved in the fatigue verification, e.g., the alternating stress intensity Salt, the penalty factor Ke and the cumulative damage factor U, and relevant computational procedures applicable for the assessment of low-cycle fatigue failure using strain-controlled data, are particularly addressed. A so-called simplified elastic-plastic discontinuity analysis for alternative verification when fatigue requirements found unsatisfactory, and the procedures provided in NB-3600 for evaluating the alternating stress intensity S,j,, are reviewed in detail. An in-depth discussion is given to alternative procedures suggested earlier by the authors using nonlinear finite element analyses, which uses a nonlinear finite element analysis for directly determining the alternating stress, thus eliminating uncertainties resulted from the use of the penalty factor Ke. Using this alternative, unavoidable plastic strains can be correctly taken into account in a computationally affordable way, and the reliability of the verification will not be affected by uncertainties introduced in the simplified elastic-plastic analysis.展开更多
文摘目的探讨原发性高血压(EH)患者血清转化生长因子β1(TGF-β1)水平对血压变异性(BPV)及昼夜节律的影响。方法将2016年8月至2018年10月收治的118例EH患者纳入观察组,同时,将同期体检的120例健康人群纳入对照组;对比2组血清TGFβ-1水平,血压BPV及血压昼夜节律。结果观察组血清TGF-β1明显高于对照组(P<0.05)。观察组24 h SBP、dSBP、nSBP、mSBP均明显高于对照组,而其24 h DBP、dDBP、nDBP、mDBP均明显低于对照组(P<0.05)。观察组24 h SBPV、24 h DBPV、nDBPV、mSBPV与对照组相比差异有统计学意义(P<0.05)。观察组不同水平血清TGF-β1 BPV差异有统计学意义(P<0.05);且观察组血清TGF-β1与24 h SBPV、mSBPV呈正相关(r=0.541,0.5552;P均<0.05),而与24 h DBPV、nDBPV呈负相关(r=-0.477,-0.468;P均<0.05)。观察组发生昼夜节律异常率为95.76%,对照组发生昼夜节律异常率为56.67%,差异有统计学意义(P<0.05)。结论EH患者血清TGF-β1水平明显较高,BPV在一定范围高于正常人群,昼夜节律异常率较高,且其血清TGF-β1水平与BPV具有相关性。
基金supported by Science and Technology Plan-ning Project of Guangdong Province,China(No.2011B031800205)
文摘In this study, we prepared PLLA/bpV（pic） microspheres, a bpV（pic） controlled release system and examined their ability to protect nerve cells and promote axonal growth. PLLA microspheres were prepared by employing the o/w single emulsification-evaporation technique. Neural stem cells and dorsal root ganglia were divided into 3 groups in terms of the treatment they received： a routine medium group（cultured in DMEM）, a PLLA microsphere group（DMEM containing PLLA microspheres alone） and a PLLA/bpV（pic） group [DMEM containing PLLA/bpV（pic） microspheres]. The effects of PLLA/bpV（pic） microspheres were evaluated by the live-dead test and measurement of axonal length. Our results showed that PLLA/bpV（pic） granulation rate was（88.2±5.6）%; particle size was（16.8±3.1）%, drug loading was（4.05±0.3）%; encapsulation efficiency was（48.5±1.8）%. The release time lasted for 30 days. In PLLA/bpV（pic） microsphere group, the cell survival rate was（95.2 ±4.77）%, and the length of dorsal root ganglion（DRG） was 718±95 μm, which were all significantly greater than those in ordinary routine medium group and PLLA microsphere group. This preliminary test results showed the PLLA/bpV（pic） microspheres were successfully prepared and they could promote the survival and growth of neural cells in DRG.
文摘In this paper, fatigue verification of Class 1 nuclear power piping according to ASME Boiler ＆ Pressure Vessel Code, Section III, NB-3600, is addressed. Basic design requirements and relevant verification procedures using Design-By-Analysis are first reviewed in detail. Thereafter, a so-called simplified elastic-plastic discontinuity analysis for further verification when the basic requirements found unsatisfactory is examined and discussed. In addition, necessary computational procedures for evaluating alternating stress intensities and cumulative damage factors are studied in detail. The authors＇ emphasis is placed on alternative verification procedures, which do not violate the general design principles upon which the code is built, for further verification if unsatisfactory results are found in the simplified elastic-plastic analysis. An alternative which employs a non-linear finite element computation and a refined numerical approach for re-evaluating the cumulative damage factors is suggested. Using this alternative, unavoidable plastic strains can be correctly taken into account in a computationally affordable way, and the reliability of the verification will not be affected by uncertainties introduced in the simplified elastic-plastic analysis through the penalty factor Ke and other simplifications.
文摘Fatigue verification of Class 1 nuclear power piping according to ASME Boiler and Pressure Vessel Code, Section III, NB-3600, which is often discussed in connection to power uprate and life-extension of aging reactors in recent years, is dealt with. Key parameters involved in the fatigue verification, e.g., the alternating stress intensity Salt, the penalty factor Ke and the cumulative damage factor U, and relevant computational procedures applicable for the assessment of low-cycle fatigue failure using strain-controlled data, are particularly addressed. A so-called simplified elastic-plastic discontinuity analysis for alternative verification when fatigue requirements found unsatisfactory, and the procedures provided in NB-3600 for evaluating the alternating stress intensity S,j,, are reviewed in detail. An in-depth discussion is given to alternative procedures suggested earlier by the authors using nonlinear finite element analyses, which uses a nonlinear finite element analysis for directly determining the alternating stress, thus eliminating uncertainties resulted from the use of the penalty factor Ke. Using this alternative, unavoidable plastic strains can be correctly taken into account in a computationally affordable way, and the reliability of the verification will not be affected by uncertainties introduced in the simplified elastic-plastic analysis.
