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集中空调通风系统可以改善室内小气候,同时也是室内空气污染物重要来源。我国发布《公共场所集中空调通风系统卫生学评价规范》(WS/T395-2012)和《公共场所集中空调通风系统清洗消毒规范》(WS/T396-2012)至今已有8年历史,在科学性、适应性上是否满足当前需要,需要对其进行较为全面的评估。通过对我国现行规范与发达国家规范进行分析对比,为我国现行规范的修订和补充提供依据及合理化建议。本研究提出对室外新风口距污染源分离距离应作出规定;增加盘管表面冷凝水细菌总<1000 CFU/ml卫生学指标;加湿器加湿水应达到饮用水标准;改进风管积尘的采样方法;给出冷凝水中军团菌和菌落总数限值4条建议。  相似文献   
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摘要〓目的〓研究四腔水箱在腹外科腔镜电凝线擦拭法清洗消毒中的应用效果。方法〓通过目测法和ATP生物荧光法,对本研究的四腔水箱用于腹外科腔镜电凝线的清洗效果进行评价。结果〓传统治疗碗清洗的206件腔镜电凝线清洗质量合格率为86.4%,四腔水箱清洗的206件腹腔镜电凝线清洗质量合格率为94.6%,差异有统计学意义(P<0.01)。用四腔水箱清洗腔镜电凝线擦拭过程中的护理人员满意度较高。结论〓四腔水箱可提高腹外科腔镜电凝线清洗质量和护理人员满意度。  相似文献   
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The mucosal glycocalyx of the ocular surface constitutes the point of interaction between the tear film and the apical epithelial cells. Membrane-associated mucins (MAMs) are the defining molecules of the glycocalyx in all mucosal epithelia. Long recognized for their biophysical properties of hydration, lubrication, anti-adhesion and repulsion, MAMs maintain the wet ocular surface, lubricate the blink, stabilize the tear film and create a physical barrier to the outside world. However, it is increasingly appreciated that MAMs also function as cell surface receptors that transduce information from the outside to the inside of the cell. A number of excellent review articles have provided perspective on the field as it has progressed since 1987, when molecular cloning of the first MAM was reported. The current article provides an update for the ocular surface, placing it into the broad context of findings made in other organ systems, and including new genes, new protein functions and new biological roles. We discuss the epithelial tissue-equivalent with mucosal differentiation, the key model system making these advances possible. In addition, we make the first systematic comparison of MAMs in human and mouse, establishing the basis for using knockout mice for investigations with the complexity of an in vivo system. Lastly, we discuss findings from human genetics/genomics, which are providing clues to new MAM roles previously unimagined. Taken together, this information allows us to generate hypotheses for the next stage of investigation to expand our knowledge of MAM function in intracellular signaling and roles unique to the ocular surface.  相似文献   
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目的 研究影响医疗器械超声清洗效果的因素,为合理改进医院消毒供应中心超声清洗医疗器械的方法和流程提供参考依据。方法 采用超声波能量检测瓶和超声波声强测试仪对超声波效能进行检测,采用管腔型清洗效果检测卡对超声波清洗效果进行检测。结果 能量瓶平均变色时间、超声波声强、检测卡平均清洗合格时间比较,脱气组和未脱气组差异有统计学意义(P<0.05);器械规则摆放组和堆叠摆放组差异有统计学意义(P<0.05);单层摆放组和双层摆放组差异有统计学意义(P<0.05),层数相同条件下单筐组和双筐组在相同测试位点差异无统计学意义(P>0.05)。4种品牌清洗剂中A品牌的清洗效果最好、清洗速度最快,但能量瓶平均变色时间和声强测试差异无统计学意义(P>0.05)。清洗剂加注量在1:100、清洗温度在45℃时清洗效果最好。超声时间2 h内清洗剂的酶活力均在1 600 U左右,差异无统计学意义(P>0.05)。结论 脱气、器械摆放、器械装载方式以及不同清洗剂、清洗温度均能导致超声清洗效能的改变,合理选择清洗条件才能够使医疗器械超声清洗达到满意效果。  相似文献   
6.
BackgroundThe onset of carious lesions and periodontal disease originates in plaque formed from dental bacteria. Appropriate plaque control is therefore important. Dental floss is one instrument used to control plaque. The influence of guardians is an important factor in whether children use dental floss regularly. However, the use of dental floss among school-age children and the relationship between use and family background has yet to be examined.AimIn this study, we conducted a questionnaire survey to examine rates of dental floss use and other related factors among elementary school children and their guardians.MethodsSurveys were sent to 298 guardians of children in grades 1–6 at an elementary school in Japan and 283 valid responses were received. Statistical analyses were carried out, with child’s use of dental floss as a dependent variable and grade, sex, guardian assistance with child's tooth brushing, frequency of child’s dental check-ups, and guardian's use of dental floss as independent variables.ResultsThe results revealed that 18.4% of children used dental floss compared with 52.7% of guardians, suggesting that the rate of usage among children is much lower than that among guardians. Logistic regression analysis further revealed that guardian's use of dental floss was significantly related to dental floss use among children.ConclusionThe guardian's use of dental floss was associated with dental floss use among their children in this group of Japanese elementary school.  相似文献   
7.
目的:评价多酶预处理溶液联合超声对口腔内科器械的清洗效果。方法:选取2019年2月~5月我院口腔内科常规使用并进行消毒的器械620支,随机分为两组,分别用多酶预处理溶液(对照组)和多酶预处理溶液联合超声清洗(实验组)处理。比较两组目测清洗合格率以及STF清洗效果检测卡合格率。结果:实验组器械目测合格率以及STF清洗效果检测卡检测合格率均高于对照组(P<0.05)。结论:多酶预处理溶液联合超声清洗对于口腔内科器械具有更加有效和安全的清洗效果。  相似文献   
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In this prospective study, 120 teeth consisting of maxillary and mandibular canines and premolars were divided into three groups each containing 40 teeth. The teeth were assigned randomly in quadrants to three different periodontal treatment protocols. The first group was treated with professional prophylaxis only. The second group received additional deep scaling. With the third group, additional surgical periodontal flap surgery and scaling was performed. Both papillary bleeding index (PBI) and probing depth (PD) were evaluated before, during and after treatment. During the subsequent prosthetic treatment phase all teeth were then used as telescope abutments supporting a removable prosthesis. The documentation of the attachment level (AL) was then used as a clinical parameter. One year after the incorporation of telescopic removable partial dentures (RPDs), PD, PBI and AL were again evaluated. The resulting periodontal parameters were compared between the different groups using the general linear model (GLM) repeated measures and the Kruskal-Wallis test for non-parametric variables. Differences within the three treatment groups were determined using the t-test, e.g. the Wilcoxon test for dependent variables (P < 0.05). A significant decrease in inflammatory indices (PBI) was found for all types of periodontal treatment (P < 0.03 for all groups). Additionally, the reduction in PD was significant for all of the three groups (P < 0.001 for all groups). The greatest reduction in PD was observed in the group in which a surgical approach was used. Evaluation of the attachment level after the incorporation of the telescopic RPDs showed that tooth position did not influence the periodontal prognosis and that the use of telescopic RPDs exerted no ascertainable negative influence on the periodontium of the abutment teeth.  相似文献   
10.
The cleaning capacity of rotary Ni-Ti instrumentation using Profile GT files, coupled with irrigation energised by ultrasound, was evaluated. Thirty-six human mandibular incisors were instrumented in vitro using the crown-down technique with the Profile GT system to 1 mm from the anatomical apex to a size 30.04 taper file. The instrumented teeth were then divided randomly into four groups where various final irrigations were used: Group I: 100 ml of 1% NaOCl with a Luer-Lok syringe (control group); Group II, Group III and Group IV: final irrigation with 100 ml of 1% NaOCl energised by ultrasound for 1, 3 and 5 min, respectively. After biomechanical preparation, the apical thirds of the roots were submitted to histological processing and examination. The specimens were analysed at 40x magnification and the images submitted to morphometric analysis with an integration grid. anova showed a statistically significant difference (P < 0.01) between the irrigation techniques. Group I (Luer-Lok syringe) showed the highest percentage of debris (35.81 +/- 4.49) and was statistically different from the other groups energised by ultrasound: Group II (27.28 +/- 4.49), Group III (24.39 +/- 5.72) and Group IV (18.46 +/- 5.25). It was concluded that rotary instrumentation using Ni-Ti files associated with final irrigation of 1% NaOCl energised by ultrasound leads to better debris removal from the apical third of mesio-distally flattened root canal.  相似文献   
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