皮肤衰老血管改变及脂肪干细胞对其治疗的研究进展

皮肤年轻化一直以来是美容医学领域的研究热点,因此认识皮肤衰老的发生机制和防治措施尤为重要。皮肤衰老的主要原因是胶原和血管方面的改变,近年来研究发现血管的改变与皮肤衰老有着密切联系,包括依赖年龄而发生的皮肤微血管数量的减少、血管分布和结构的改变等,从而出现干燥、无光泽等皮肤衰老表现。本文拟对皮肤衰老中血管的改变以及血管相关发生机制和影响因素等研究现状作一综述,并就干细胞治疗中脂肪干细胞在皮肤衰老血管方面的治疗作用进行探讨,以期为改善皮肤衰老的基础研究和临床治疗提供新思路。

保温砂浆外墙外保温系统在不利条件下温度变化规律

为得到保温砂浆外墙外保温系统耐候性保温效果及机理,对其进行耐候性试验,通过布点监测得到各构造层瞬态温度场,计算各层温度变化率及层间温度衰减系数,以对比不同结构层温度变化程度及保温能力。结果表明:在热雨循环15~70℃温度范围内,基层温度最大变化幅度仅为9.12℃,在热冷循环-20~50℃温度范围内,基层温度最大变化幅度仅为28.21℃,其温度改变幅度相较于另外两层明显平缓;基层与保温层层间温度衰减系数明显大于保温层与饰面层。可见系统保温性能优良,保温砂浆层是主要保温结构。

基于德尔菲法构建医学院校教师教学质量评价档案

目的构建教师教学质量评价档案。方法?采用德尔菲法确定教师教学质量评价档案的组成,明确档案中教学质量综合评价得分的量化构成。结果专家积极系数为100%,专家权威系数为0.85。评价档案组成的专家一致性系数在0.24~0.32(所有P值均<0.01),包括5种不同主体的评教信息。教学质量综合评价得分各组成权重的专家一致性系数为0.47~0.92(所有P值均<0.01),权重为校级督导评教40%,院级督导评教20%,学生评教40%。结论本研究构建的教学质量评价档案体系有较好的实用价值,但仍需在实际应用中进一步验证和完善。

Does polar amplification exist in Antarctic surface during the recent four decades?

There are numerous studies on polar amplification and its influence on mid-latitude weather and climate.However,assessments on whether polar amplification occurs in Antarctica are rarely conducted.Based on the latest atmospheric reanalysis of ERA5 produced by European Centre for Medium-Range Weather Forecasts(ECMWF),we have defined the Antarctic amplification index,and calculated the trend of annual and seasonal Surface Air Temperature(SAT)mean during 1979-2019 for Antarctic Ice Sheet(AIS)and the trend mean of different meridional sectors of Antarctic sub regions including East Antarctic Ice Sheet(EAIS),West Antarctic Ice Sheet(WAIS)and Antarctic Peninsula(AP).Antarctic amplification shows regional differences and seasonal variations.Antarctica shows a slight warming with the largest magnitude in AP.The temperature anomalies indicate the least fluctuations in austral summer,and the more fluctuations in winter and spring.In austral summer,the warming trend domains EAIS and WAIS,while the cooling trend appears over AP.The zonal mean in Southern Hemisphere maintains a warming trend in the low latitudes,and fluctuates greatly in the middle and high latitudes.The strongest Antarctic amplification phenomenon occurs in spring,with the amplification index of 1.20.For AP,the amplification occurs in austral autumn,and the amplification index is 2.16.At South Pole and the surrounding regions,SAT for land only fluctuates largely and shows different trends in different seasons.The mechanism of Antarctic amplification is unclear till now,and its research suffers from the limitation of measured data.This suggests that future research needs progress in comprehensive ground observation network,remote sensing data accumulation,and high-resolution climate modeling with better representation of both atmospheric and cryospheric processes in Antarctica.

蛋白琥珀酸铁口服液治疗异常子宫出血继发性贫血临床研究

目的 探讨蛋白琥珀酸铁口服液治疗异常子宫出血继发性贫血的有效性及安全性。方法 收集2021年4月至2022年9月在黑龙江中医药大学附属第一医院妇科被确诊为异常子宫出血继发性贫血的150例患者纳入研究,所有患者均在对症止血治疗的基础上,采用蛋白琥珀酸铁口服溶液(盛雪元)治疗,观察治疗后第2周和第4周的临床总有效率,血红蛋白、血清铁、血清铁蛋白等疗效指标变化情况及不良反应发生情况。结果 治疗后2周临床总有效率为75.3%,治疗后4周临床总有效率为90.4%,二者比较差异有统计学意义(χ^(2)=11.680,P<0.05);治疗后,血红蛋白、血清铁、血清铁蛋白水平与治疗前比均上升,差异均有统计学意义(P<0.05);总铁结合力与治疗前比下降,差异有统计学意义(P<0.05),且治疗后4周各项指标的恢复情况较治疗后2周显著。治疗后无不良反应发生。结论 蛋白琥珀酸铁口服液治疗妇科异常子宫出血继发性贫血有很好的疗效并具有安全性,值得临床推广。

A shallow ice core from East Greenland showing a reduction in black carbon during 1990-2016

This study reports on the measurements of ion and refractory black carbon(rBC)concentrations in a shallow(10.96 m)ice core sample which was drilled from the field site of the East Greenland Ice Core Project(EGRIP)in July,2016.The results provide a recent record of rBC deposition in the East Greenland ice sheet from 1990 to 2016.The annual variability in oxygen(δ^(18)O)and hydrogen(δD)isotopic compositions indicated that notably warm events occurred since 2008.Peaks in rBC occurred during summer seasons,which may be attributed to the burning of biomass in boreal summer.The rBC record and analysis of historical air trajectories using the HYSPLIT model indicated that anthropogenic BC emissions from Russia,North America and Europe contributed to the majority of rBC deposition in the Greenland region,and a reduction in anthropogenic BC consumption in these areas played a dominant role in the decrease in BC concentrations since 2000.This record also suggests that the emissions from the East Asian region(China)contributed very little to the recorded BC concentrations in East Greenland ice core.The model results indicated that radiative forcing due to BC had decreased significantly since 1990,and had remained below 0.02W m^(-2) since 2000.

工作场所空气中氰化氢的分光光度法测定

以GBZ/T 160.29-2004《工作场所空气有毒物质测定无机含氮化合物—氰化氢和氰化物的异菸酸钠-巴比妥酸钠分光光度法》为基础,在不同显色时间及显色温度下进行吸光度测定,选择最佳的显色时间是20 min,最佳的显色温度为室温(20±2)℃。方法测定范围为0.01~0.40μg/ml,标准曲线y=1.9558x+0.0087,回归方程相关系数为0.9998,方法检出限为0.01μg/ml,最低检出浓度为0.01 mg/m^(3)(以采集2 L空气样品计),定量下限为0.02μg/ml,最低定量浓度为0.02 mg/m^(3)(以采集2 L空气样品计),相对标准偏差RSD在0.8%~3.0%,加标回收率为95%~104%。提示,该方法结果满意,适合工作场所空气中氰化氢的测定。