不同强度耐力训练对新兵自主神经调节功能的影响

目的评价不同强度的耐力训练对新兵自主神经功能的影响,为优化军事训练提供科学的依据。方法72名健康男性新兵,随机分为现行军体训练组、有氧耐力组、无氧耐力组,进行连续8周训练。分别于训练前、训练末进行5 min心率变异性(HRV)分析、冷加压试验(CPT)及血浆去甲肾上腺素(NE)、肾上腺素(EPI)、肾素活性(RA)及神经肽Y(NPY)检测。结果训练前各指标组间差异无显著性。训练8周末,现行训练组HFn(52±11)较训练前(59±12)显著降低(P<0.05),但LFn(43±12)、LF/HF(0.87±0.35)均较训练前(36±11)、(0.67±0.32)〕有显著增加(P<0.05);有氧耐力组HFn(62±11)均较训练前(53±14)显著增加(P<0.05),但LFn(36±8)、LF/HF(0.64±0.28)与训练前(39±12)、(0.77±0.33)相比呈下降趋势;无氧耐力组HRV无显著变化。训练8周末与静态时比较,无氧耐力组CPT中HR增加值〔(6.46±6.79)b.min-1〕显著低于现行训练组〔(24.00±22.64)b.min-1〕和有氧耐力组〔(17.11±15.22)b.min-1〕的增加值(P<0.05)。现行训练组的NE〔(152.17±31.51)pg.mL-1)〕显著高于有氧耐力组〔(109.31±18.77)pg.mL-1〕和无氧耐力组〔(104.92±19.36)pg.mL-1)〕(P<0.01)。现行训练组RA〔(4.33±2.08)pg.mL-1)〕显著高于有氧耐力组〔(1.97±1.79)pg.mL-1)〕和无氧耐力组〔(2.74±1.06)pg.mL-1)〕(P<0.01)。结论耐力训练对自主神经调节能力的影响主要取决于负荷强度,现行军体训练接近极限强度,其对机体有潜在危害,故应进行规范的有氧、无氧耐力训练。     

急性高原病发病前后血管内皮生长因子及其受体水平变化

目的探讨人群急进高原前后血管内皮生长因子(vascular endothelial growth factor,VEGF)和受体VEGFR-1(fms-like tyrosine kinase-1,flt-1)、VEGFR-2(fetal liver kinase-1/kinase insert domain-containing receptor,flk-1/KDR)的表达变化及其与急性高原病(acute mountain sickness,AMS)发病的关系,为发现和保护易感人群提供理论依据。方法以2000名健康新兵为研究对象,分别在急进高原前后抽取静脉血备用。以症状评分法调查急进高原后AMS的发病率,随机选取20名AMS发病对象为AMS组,20名未发病对象为对照组,采用ELISA法检测急进高原前后两组血浆VEGF、VEGFR-1、VEGFR-2浓度的变化。结果 2000名研究对象中AMS的发病率为34.3%。与平原地区相比,AMS组急进高原后血浆VEGF浓度明显升高且差异有统计学意义(t=2.799,P=0.011),血浆VEGFR-1和VEGFR-2浓度无明显变化;对照组急进高原后血浆VEGF、VEGFR-1和VEGFR-2浓度变化无统计学意义(P0.05)。急进高原前后AMS组血浆VEGF浓度均明显高于对照组(t=2.461,P=0.018;t=2.698,P=0.010),而血浆VEGFR-1、VEGFR-2浓度与对照组相比均无明显差异。结论血浆VEGF浓度有可能作为一个敏感指标在急进高原前筛选AMS易感者,而血浆VEGFR-1、VEGFR-2浓度与AMS的发生无相关性。     

有氧耐力训练对壬基酚染毒大鼠血中心钠素水平的影响

目的 探讨有氧耐力训练对壬基酚(NP)染毒大鼠心血管内分泌功能的影响.方法将8周龄健康清洁级SD雄性大鼠72只随机分为0、11、44、176mg/kgNP染毒训练和未训练组,每组9只.采用腹腔注射方式染毒,染毒剂量为5 ml/kg,连续染毒8周.训练组进行无负重有氧耐力游泳,每天游泳1次,每次90 min,每周6次.测定血浆心钠素(ANP)含量.结果 与未训练对照组比较,0、11 mg/kg NP染毒训练组大鼠ANP水平较高,44、176 mg/kg NP染毒训练组和44、176mg/kg NP染毒未训练组大鼠ANP水平较低,差异均有统计学意义(P＜0.01).与同剂量未训练组比较,0、11、44、176mg/kg NP染毒训练组大鼠ANP水平较高,差异均有统计学意义(P＜0.05或P＜0.01).且无论是训练组还是未训练组,大鼠ANP水平均随NP染毒剂量的升高而降低.结论 有氧耐力训练对NP染毒大鼠ANP水平的降低具有拮抗作用.     

运动训练与心血管压力感受器反射敏感性的关系

目的 通过测量志愿者连续3个月有氧和无氧训练中心血管压力感受器反射敏感性(BRS),了解运动训练对BRS的影响规律,为健康体检人群制定合理科学的训练方案提供帮助.方法 16名男性健康志愿者,随机分为两组,其中有氧与无氧组合训练组(组1)7名,单纯有氧训练组(组2)9名,共进行12周训练.在训练前、训练的第4、8、12周...     

DESIGN AND EVALUATION OF TRAINING CENTER FOR HIGH ALTITUDE ACCLIMATIZATION BASED ON OXYGEN-ENRICHED AIR

目的 建立基于富氧环境的高原习服训练中心,并评价其效果.方法 在海拔3570 m利用分子筛制氧机供氧和自动供氧控制系统,模拟较低生理等效高度,建立习服训练中心.将24名男性急性高原反应(AMS)患者随机分成训练组和对照组,每组12人.训练组在O2含量分别为26.0％、24.5％、23.0％和21.5％的富氧环境中进行运动训练各1d;对照组处于自然低氧环境中,不进行运动训练.将训练组训练期间和训练结束后1d的收缩压、舒张压、心率、血氧饱和度及AMS评分与同期对照组值进行比较.结果 训练组进入习服训练中心训练后,血氧饱和度有所改善,训练1～4d和训练后1d,AMS评分分别为2.08±1.17、1.67±0.65、1.50±0.79、1.33±0.89、0.58±0.67,均明显低于对照组(分别为5.50±0.08、5.58±0.09、4.50±1.17、3.92±0.09、3.42±0.79),差异有显著性(P＜0.01).结论 在高原习服训练中心通过阶梯式调节生理等效高度并进行运动训练,能及时缓解急性高原反应症状,缩短习服时间.     

基于富氧环境的高原习服训练中心的设计与评价

目的建立基于富氧环境的高原习服训练中心,并评价其效果。方法在海拔3570 m利用分子筛制氧机供氧和自动供氧控制系统,模拟较低生理等效高度,建立习服训练中心。将24名男性急性高原反应(AMS)患者随机分成训练组和对照组,每组12人。训练组在O2含量分别为26.0%、24.5%、23.0%和21.5%的富氧环境中进行运动训练各1 d;对照组处于自然低氧环境中,不进行运动训练。将训练组训练期间和训练结束后1 d的收缩压、舒张压、心率、血氧饱和度及AMS评分与同期对照组值进行比较。结果训练组进入习服训练中心训练后,血氧饱和度有所改善,训练1~4 d和训练后1 d,AMS评分分别为2.08±1.17、1.67±0.65、1.50±0.79、1.33±0.89、0.58±0.67,均明显低于对照组(分别为5.50±0.08、5.58±0.09、4.50±1.17、3.92±0.09、3.42±0.79),差异有显著性(P<0.01)。结论在高原习服训练中心通过阶梯式调节生理等效高度并进行运动训练,能及时缓解急性高原反应症状,缩短习服时间。     

急进高原自主神经功能变化与急性高原反应的关系

目的研究急进高原前、后心血管自主神经(autonomic nervous system,ANS)功能变化及其与急性高原反应(acute mountain sickness,AMS)之间关系,揭示ANS在AMS发病中的作用,探求预防AMS的可能途径。方法对99名健康男性青年在海拔450m平原和空运急进3700m高原后2~4d内进行心率变异性(heart rate variability,HRV)和冷加压试验(cold pressor test,CPT)检测;在急进高原后1~5d接受AMS发病情况调查。结果急进高原后第1天AMS发病率92%,其中,中重度AMS占10%、轻度占36%、基本无反应占54%。LF/HFn随AMS程度减轻而减少,HFn随AMS程度加重而增加。中重度、轻度、基本无AMS反应组平原时收缩压(SBP)分别为(123.42±7.14)mmHg、(120.6±11.22)mmHg、(122.58±10.92)mmHg,均显著高于无反应组(111.31±9.48)mmHg,(P<0.05);中重度AMS组在平原CPT后心率(HR)变化幅度〔(7.57±8.22)b/min〕显著低于基本无反应组〔(25.47±19.26)b/min,(P<0.05)〕。急进高原后,中重度、轻度、基本无AMS反应组CPT后SBP变化幅度分别为(8.14±4.95)mmHg、(9.56±7.77)mmHg、(9.97±6.80)mmHg,均显著低于无反应组〔(17.00±12.75)mmHg,(P<0.05)〕;HR变化幅度分别为(11.13±6.08)b/min、(10±7.5)b/min、(12.25±8.14)b/min,均显著低于无反应组(〔19.71±9.35)b/min,P<0.05〕。AMS症状积分与平原时LF/HF正相关(r=0.437,P<0.01),与平原时CPT后HR变化幅度呈负相关(r=-0.35,P=0.01)。结论平原交感神经活动较高者其ANS的应激调节能力相对较小,对AMS易感性较高。改善ANS功能可能有助于预防AMS。     

八段锦有氧训练对尘肺患者康复效果的影响

目的探讨八段锦有氧运动对尘肺病患者肺功能、活动耐力、呼吸困难及生活质量的影响。方法以2015年5月—2018年7月期间在淄博市职业病防治院住院的148例尘肺病患者为研究对象,随机分成对照组和训练组,每组74例。对照组给予常规护理,训练组在常规护理的基础上给予八段锦有氧训练3个月。训练前后,对2组患者的第1秒用力呼气量(FEV1)、最大通气能力(MVV)和第1秒用力呼气量占用力肺活量的比率(FEV1/FVC)、Borg呼吸困难评分、6 min步行实验(6 MWT)及圣乔治呼吸问卷(SGRQ)进行分析比较。结果八段锦有氧训练3个月后训练组的肺功能指标FEV1、FEV1/FVC和MVV分别为(2.03±0.41)L、(72.6±3.22)%和(64.69±7.64)L/min,均高于对照组[(1.81±0.45)L、(70.8±5.43)%、(61.21±9.13)L/min]及本组治疗前[(1.80±0.65)L、(69.4±6.05)%、(60.87±9.59)L/min],差异均有统计学意义(均P0.05);对照组训练前后肺功能指标差异均无统计学意义(均P0.05)。八段锦训练后训练组患者的SGRQ得分(47.84±9.27)与Borg呼吸困难评分(2.6±1.5)均低于对照组(50.76±9.24、3.2±1.8)及本组治疗前(51.92±11.98、3.7±1.7),6 MWT[(431±87.7)m]高于对照组[(367±66.4)m]及本组治疗前[(349±79.3)m],差异均有统计学意义(均P0.05)。对照组干预前后6 MWT、SGRQ得分与Borg呼吸困难评分差异均无统计学意义(均P0.05)。结论八段锦有氧训练可改善尘肺患者的肺功能和呼吸困难症状,提高运动耐力,改善患者生活质量。     

高原低氧环境下大鼠RAAS水平与ACE2基因多态性

[目的]探讨大鼠血浆肾素-血管紧张素-醛固酮系统(RAAS)在高原低氧习服过程中的作用与血管紧张素转换酶2(ACE2)基因多态性的关系。[方法]将40只雄性SD大鼠随机分为4组,分别为1d(A组)、2d(B组)、3d(C组),对照组(D组西安地区,海拔5m)。3个实验组动物由西安耗时1d带到青海格尔木(海拔2700m)、2d带到西藏唐古拉(海拔5000m)、3d带到西藏那曲(海拔4500m),在不同时间点处死取材,用放射免疫法(RAI)测定大鼠血浆PRA,ATⅡ,ALD的浓度,并与对照组比较。采用PCR-RLFP检测各组大鼠ACE2基因A/G多态分布情况。[结果]血浆PRA,ATⅡ的含量呈上升态势,ALD含量逐渐下降。ACE2电泳结果显示3种片段组合分别为GG、AA、AG。平原大鼠进入高海拔地区后,ACE2基因型为GG的,血浆PRA,ATⅡ含量显著上升,ALD含量明显下降(P﹤0.01)。ACE2基因型为AA的,血浆PRA,ATⅡ含量上升,ALD含量下降(P﹤0.05)。ACE2基因型为AG的,血浆PRA,ATⅡ,ALD变化不明显(P﹥0.05)。[结论]高原低氧大鼠RAAS与ACE2基因GG、AA在高原习服中参与并发挥着重要作用。     

停训练对大鼠骨骼肌超微结构和酶的影响

[目的]研究旨在观察停训对大鼠骨骼肌的超微结构以及氧化酶与无氧酶含量的影响.[方法]采用两月龄雄性大鼠44只,随机分为正常对照组(NC,16只)与力量耐力训练组(ST,28只),通过6周跳跃性力量耐力训练后,对ST组中的12只大鼠停训6周,分别对骨骼肌中酶的含量和超微结构进行采集. [结果]通过6周的停训之后,Gn、LDH、SDH以及ATPase含量均明显降低,线粒体体积减小,数量减少. [结论]停训可明显降低机体的有氧和无氧代谢能力.     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

Occupational health hazards in mining: an overview

This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.     

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.