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室内装修后空气中甲醛浓度的变化趋势 总被引:6,自引:1,他引:5
目的 :研究室内装修后空气中甲醛浓度的变化趋势。方法 :选择装修后不同时间段的居民住宅 5 4家和公共场所经营单位 5 2家进行室内空气中甲醛浓度的测定。结果 :甲醛浓度在居民住宅装修 1年之内的超标率为 79.9%~ 85 .4 % ,1年~ 2年之间的超标率为 5 0 .0 % ,2年之后为18.3% ,3个时间段甲醛浓度超标率有显著性差异 (P<0 .0 5 )。公共场所装修半年之内甲醛含量的超标率为 6 5 .5 %~ 81.3% ,半年~ 1年为 36 .84 % ,1年之后 <15 .4 % ,3个时间段甲醛浓度超标率有显著性差异 (P<0 .0 5 )。结论 :室内装修后甲醛浓度随着装修时间的延长而逐渐降低 ,居民住宅大约需要 2年、公共场所大约需要 1年才能达到国家卫生标准。 相似文献
3.
Self-contained underwater breathing apparatus (scuba) diving has grown in popularity, with nearly 9 million sport divers in
the United States alone. Approximately 7% of the population has been diagnosed with asthma, which is similar to the percentage
of divers admitting they have asthma. Numerous concerns exist regarding subjects with asthma who choose to participate in
recreational diving. Among these concerns are pulmonary barotrauma, pneumomediastinum, pneumothorax, arterial gas embolism,
ear barotrauma, sinus barotrauma, and dental barotrauma. Despite these concerns, a paucity of information exists linking asthma
to increased risk of diving complications. However, it has long been the norm to discourage individuals with asthma from participating
in recreational scuba diving. This article examines the currently available literature to allow for a more informed decision
regarding the possible risks associated with diving and asthma. It examines the underlying physiological principles associated
with diving, including Henry’s law and Boyle’s law, to provide a more intimate understanding on physiological changes occurring
in the respiratory system under compressive stress. Finally, this article offers a framework for guiding the patient with
asthma who is interested in scuba diving. Under the right circumstances, the patient with asthma can safely participate in
recreational diving without apparent increased risk of an asthma-related event. 相似文献
4.
《Health & place》2022
Park use is associated with health, yet our understanding of park features related to their use is limited. Singapore's parks were audited for 30 micro-features, then geospatial analysis characterized micro-features scores for parks nearest to participants' homes. Adults (3,435) reported their park use and park-based physical activity. Using linear regression models, we found living near a park with higher micro-features scores was associated with more time in parks and park-based physical activity. Specific micro-features were associated with more park time (wildlife areas, water features, forested areas, unpaved trails (2–2.6 h/month, p < 0.05)) and with physical activity in parks (water features, forested areas, large playground, open green spaces (1.8–2.2 h/month, p < 0.05)). These findings could inform parks planning to support population-health. 相似文献
5.
《Health & place》2021
Previous studies observed that most COVID-19 infections were transmitted by a few individuals at a few high-risk places (e.g., bars or social gathering venues). These individuals, often called superspreaders, transmit the virus to an unexpectedly large number of people. Further, a small number of superspreading places (SSPs) where this occurred account for a large number of COVID-19 transmissions. In this study, we propose a spatial network framework for identifying the SSPs that disproportionately spread COVID-19. Using individual-level activity data of the confirmed cases in Hong Kong, we first identify the high-risk places in the first four COVID-19 waves using the space-time kernel density method (STKDE). Then, we identify the SSPs among these high-risk places by constructing spatial networks that integrate the flow intensity of the confirmed cases. We also examine what built-environment and socio-demographic features would make a high-risk place to more likely become an SSP in different waves of COVID-19 by using regression models. The results indicate that some places had very high transmission risk and suffered from repeated COVID-19 outbreaks over the four waves, and some of these high-risk places were SSPs where most (about 80%) of the COVID-19 transmission occurred due to their intense spatial interactions with other places. Further, we find that high-risk places with dense urban renewal buildings and high median monthly household rent-to-income ratio have higher odds of being SSPs. The results also imply that the associations between built-environment and socio-demographic features with the high-risk places and SSPs are dynamic over time. The implications for better policymaking during the COVID-19 pandemic are discussed. 相似文献
6.
目的比较Legiolert酶底物法与传统培养法对公共场所水体样本中嗜肺军团菌的检出效果。方法分别利用Legiolert酶底物法与传统培养法对采集于公共场所的冷却水、淋浴水样本进行嗜肺军团菌检测,并对分离株进行验证及血清分型。结果共采集并检测样品68份,传统培养法与Legiolert酶底物法的检出率分别为5.88%(4/68)及35.29%(24/68),差异有统计学意义(χ2=16.41,P<0.01)。两种方法的检测符合率为64.71%(44/68),检测效果的差异有统计学意义(配对χ2=16.41,P=0.000)。分离出的25株嗜肺军团菌血清型以LP1为主(14/25)。结论Legiolert酶底物法对公共场所水体样本中嗜肺军团菌的检出率高于传统培养法。 相似文献
7.
强兆艳 《天津医科大学学报》2001,7(1):45-47
目的:了解苯作业场所空气中苯浓度,推测苯作业发展趋势,方法:采用和平区1993-1999年39家工业企业,220个苯作业点,660个空气样品中的苯浓度值,按不同作业工种分为油漆组,化工(原料)组,粘胶组及印刷组,通过成组设计的多个样本比较的秩和检验进行分析。结果:1997年内不同作业组空气中苯平均浓度差异有显著性(H=8.00000 P<0.05),印刷组苯平均浓度高于其它作业组,其余年度中差异无显著性(P>0.05),1993-1999年,印刷组苯作业场所的苯平均浓度差异无显著性(P>0.05),结论:和平区苯作业开始由较低浓度过渡到较高浓度,以油漆业为主过渡到以印刷业为主,并且,1997年印刷组苯平均浓度超过国家卫生标准,应引起重视。 相似文献
8.
室内装修后空气中甲醛浓度的变化趋势 总被引:4,自引:1,他引:4
目的 :研究室内装修后空气中甲醛浓度的变化趋势。方法 :选择装修后不同时间段的居民住宅 5 4家和公共场所经营单位 5 2家进行室内空气中甲醛浓度的测定。结果 :甲醛浓度在居民住宅装修 1年之内的超标率为 79.9%~ 85 .4 % ,1年~ 2年之间的超标率为 5 0 .0 % ,2年之后为 18.3% ,3个时间段甲醛浓度超标率差异有显著性 (P<0 .0 5 )。公共场所装修半年之内甲醛含量的超标率为 6 5 .5 %~ 81.3% ,半年~ 1年为 36 .84 % ,1年之后小于 15 .4 % ,3个时间段甲醛浓度超标率差异有显著性 (P<0 .0 5 )。结论 :室内装修后甲醛浓度随着装修时间的延长而逐渐降低 ,居民住宅约需 2年 ,公共场所需 1年才能达到国家卫生标准 相似文献
9.
公共娱乐场所服务小姐预防艾滋病健康教育的效果评价 总被引:1,自引:0,他引:1
目的探讨对娱乐场所服务小姐的健康教育方法和行为干预模式,为在该特殊人群中实施有效的健康教育提供依据。方法对重庆市北碚区200名娱乐场所服务小姐进行有关艾滋病防治的健康教育。采用问卷调查的方法,在教育前后分别进行问卷调查。结果健康教育后服务小姐有关艾滋病知识的知晓率明显提高,传播途径的知晓率从65.3%上升至91.8%,当前预防艾滋病的主要措施的知晓率从68.9%上升至91.3%,日常生活接触不会传染艾滋病病毒的知晓率从69.9%上升至88.3%(P<0.01)。有商业性性行为者,最近一次使用安全套的比例从教育前的65.8%上升到86.2%(P<0.01)。结论对服务小姐进行多种形式的健康教育,可以提高该人群艾滋病预防控制知识和有效改善相关行为。 相似文献
10.
RP-HPLC法测定川产藏药不同产地红毛五加茎皮中腺苷的含量 总被引:2,自引:0,他引:2
目的:建立藏药红毛五加药材中腺苷的含量测定方法并比较四川不同产地红毛五加的腺苷含量。方法:采用 KromasilC_(18)(250 mm×4.6 mm,5 μm)色谱柱,以乙腈-水溶液(5:95),流速1.0 mL·min~(-1);柱温25℃;检测波长为258 nm。结果:腺苷进样量在0.07~0.69 μg内呈良好的线性关系(r=0.9993),低、中、高3种加入量的平均加样回收率(n=3)分别为99.3%,99.1%,99.2%;RSD 均为0.9%。结论:本方法简便、准确,重复性好,可用于红毛五加的质量控制。 相似文献