A semi-gas kinetics (SGK) model for performance analyses of flowing chemical oxygen-iodine laser (COIL) is presented. In this model, the oxygen-iodine reaction gas flow is treated as a continuous medium, and the effec...A semi-gas kinetics (SGK) model for performance analyses of flowing chemical oxygen-iodine laser (COIL) is presented. In this model, the oxygen-iodine reaction gas flow is treated as a continuous medium, and the effect of thermal motions of particles of different laser energy levels on the performances of the COIL is included and the velocity distribution function equations are solved by using the double-parameter perturbational method. For a premixed flow, effects of different chemical reaction systems, different gain saturation models and temperature, pressure, yield of excited oxygen, iodine concentration and frequency-shift on the performances of the COIL are computed, and the calculated output power agrees well with the experimental data. The results indicate that the power extraction of the SGK model considering 21 reactions is close to those when only the reversible pumping reaction is considered, while different gain saturation models and adjustable parameters greatly affect the output power, the optimal threshold gain range, and the length of power extraction.展开更多
目的探讨小剂量去甲肾上腺素(NE)对采取蛛网膜下腔-硬膜外联合麻醉(CSEA)下剖宫产术分娩新生儿氧摄取率(ERO_(2))及血气分析结果影响。方法选择2018年4月至2021年3月淮安市第一人民医院收治的98例拟采取CSEA剖宫产术产妇为研究对象。采...目的探讨小剂量去甲肾上腺素(NE)对采取蛛网膜下腔-硬膜外联合麻醉(CSEA)下剖宫产术分娩新生儿氧摄取率(ERO_(2))及血气分析结果影响。方法选择2018年4月至2021年3月淮安市第一人民医院收治的98例拟采取CSEA剖宫产术产妇为研究对象。采用随机数字表法,将其分为研究组(n=49,麻醉穿刺成功后,采用微量泵静脉输注100μg NE)与对照组(n=49,麻醉穿刺成功后,不再给予任何血管活性药物)。采用回顾性分析方法,比较2组产妇及分娩新生儿以下指标。①产妇一般临床资料及手术情况(术中尿量、总输液量、出血量及追加NE产妇占比);②新生儿ERO_(2)与生后1 min Apgar评分及血气分析[动脉血二氧化碳分压(PaCO_(2))、脉搏血氧饱和度(SaO_(2))及动脉血氧分压(PaO_(2))];③产妇术中不良反应总体发生率;④新生儿加压给氧与气管插管治疗情况。本研究遵循的程序符合淮安市第一人民医院伦理委员会制定的伦理学标准,得到该委员会批准(伦审号:YX-2021-156-01),并于所有产妇签署临床研究知情同意书。结果①2组产妇分娩年龄、分娩孕龄、术前人体质量指数(BMI)等一般临床资料比较,差异均无统计学意义(P>0.05)。②2组产妇术中尿量、总输液量及出血量比较,差异均无统计学意义(P>0.05);对照组术中追加NE产妇占比低于研究组,并且差异有统计学意义(P<0.05)。③2组新生儿ERO_(2)、PaCO_(2)、SaO_(2)、PaO_(2)比较,差异均无统计学意义(P>0.05);后生1 min Apgar评分比较,差异亦无统计学意义(P>0.05)。④2组产妇术中不良反应总发生率比较,差异无统计学意义(P>0.05)。⑤2组新生儿均无需气管插管,研究组、对照组新生儿中,2例给予加压给氧治疗。2组新生儿加压给氧占比比较,差异无统计学意义(χ^(2)=0.71,P=0.399)。结论术前小剂量NE对CDSA剖宫产术分娩新生儿的氧摄取及血气分析无明显影响,但是可降低术中追加血管活性药物比例,并且安全可靠。展开更多
目的评价高强度间歇训练(HIIT)对高血压患者的干预效果。方法计算机检索PubMed、Web of Science、The Cochrane Library、EBSCO、万方数据知识服务平台、中国知网及维普网等数据库,检索时间为建库至2018年8月,筛选检索有关HIIT对高血压...目的评价高强度间歇训练(HIIT)对高血压患者的干预效果。方法计算机检索PubMed、Web of Science、The Cochrane Library、EBSCO、万方数据知识服务平台、中国知网及维普网等数据库,检索时间为建库至2018年8月,筛选检索有关HIIT对高血压患者干预效果的随机对照试验。在药物治疗基础上,对照组患者进行常规活动或中等强度运动,试验组患者进行HIIT。比较两组患者干预后收缩压、舒张压、最大摄氧量(VO_2max)、静息心率、体质指数(BMI)。采用RevMan 5.3软件进行Meta分析。结果最终纳入6篇文献,其中英文文献5篇、中文文献1篇,共包括253例患者。Meta分析结果显示,试验组患者干预后收缩压〔加权均数差(WMD)=-4.58,95%CI(-7.51,-1.65)〕、舒张压〔WMD=-2.15,95%CI(-3.98,-0.32)〕、静息心率〔WMD=-3.24,95%CI(-5.82,-0.65)〕低于对照组(P<0.05),VO_2max高于对照组〔WMD=3.24,95%CI(1.23,5.25),P<0.05〕;两组患者干预后BMI比较,差异无统计学意义〔WMD=-0.54,95%CI(-1.87,0.78),P>0.05〕。6篇文献均未报道明显不良事件。纳入文献数量较少,无法分析发表偏倚,故不能排除发表偏倚的可能。结论现有文献证据表明,HIIT能有效提高1～2级或药物控制良好的高血压患者降压效果及VO_2max,减慢静息心率,增加心肺耐力,但对BMI无明显影响。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.10032050).
文摘A semi-gas kinetics (SGK) model for performance analyses of flowing chemical oxygen-iodine laser (COIL) is presented. In this model, the oxygen-iodine reaction gas flow is treated as a continuous medium, and the effect of thermal motions of particles of different laser energy levels on the performances of the COIL is included and the velocity distribution function equations are solved by using the double-parameter perturbational method. For a premixed flow, effects of different chemical reaction systems, different gain saturation models and temperature, pressure, yield of excited oxygen, iodine concentration and frequency-shift on the performances of the COIL are computed, and the calculated output power agrees well with the experimental data. The results indicate that the power extraction of the SGK model considering 21 reactions is close to those when only the reversible pumping reaction is considered, while different gain saturation models and adjustable parameters greatly affect the output power, the optimal threshold gain range, and the length of power extraction.
文摘目的探讨小剂量去甲肾上腺素(NE)对采取蛛网膜下腔-硬膜外联合麻醉(CSEA)下剖宫产术分娩新生儿氧摄取率(ERO_(2))及血气分析结果影响。方法选择2018年4月至2021年3月淮安市第一人民医院收治的98例拟采取CSEA剖宫产术产妇为研究对象。采用随机数字表法,将其分为研究组(n=49,麻醉穿刺成功后,采用微量泵静脉输注100μg NE)与对照组(n=49,麻醉穿刺成功后,不再给予任何血管活性药物)。采用回顾性分析方法,比较2组产妇及分娩新生儿以下指标。①产妇一般临床资料及手术情况(术中尿量、总输液量、出血量及追加NE产妇占比);②新生儿ERO_(2)与生后1 min Apgar评分及血气分析[动脉血二氧化碳分压(PaCO_(2))、脉搏血氧饱和度(SaO_(2))及动脉血氧分压(PaO_(2))];③产妇术中不良反应总体发生率;④新生儿加压给氧与气管插管治疗情况。本研究遵循的程序符合淮安市第一人民医院伦理委员会制定的伦理学标准,得到该委员会批准(伦审号:YX-2021-156-01),并于所有产妇签署临床研究知情同意书。结果①2组产妇分娩年龄、分娩孕龄、术前人体质量指数(BMI)等一般临床资料比较,差异均无统计学意义(P>0.05)。②2组产妇术中尿量、总输液量及出血量比较,差异均无统计学意义(P>0.05);对照组术中追加NE产妇占比低于研究组,并且差异有统计学意义(P<0.05)。③2组新生儿ERO_(2)、PaCO_(2)、SaO_(2)、PaO_(2)比较,差异均无统计学意义(P>0.05);后生1 min Apgar评分比较,差异亦无统计学意义(P>0.05)。④2组产妇术中不良反应总发生率比较,差异无统计学意义(P>0.05)。⑤2组新生儿均无需气管插管,研究组、对照组新生儿中,2例给予加压给氧治疗。2组新生儿加压给氧占比比较,差异无统计学意义(χ^(2)=0.71,P=0.399)。结论术前小剂量NE对CDSA剖宫产术分娩新生儿的氧摄取及血气分析无明显影响,但是可降低术中追加血管活性药物比例,并且安全可靠。
