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41.
陶瑞卿 《四川生殖卫生学院学报》2007,(6):32-35,55
公共产品涉及千家万户的切身利益,近10多年来,部分公共产品价格变化又多以超过国民经济发展速度提高,怎样正确认识和判断其价格的合理性,具有十分重要的现实意义。本文分析了我国公共产品的价格类型,定价机制,阐明了我国公共产品的价格约束制度构建的主要内容,希望为政府及相关部门工作提供有益的帮助。 相似文献
42.
Study ObjectivesWe characterized vigilance deterioration with increasing time-on-task (ToT) during recurrent sleep restriction of different extents on simulated weekdays and recovery sleep on weekends, and tested the effectiveness of afternoon napping in ameliorating ToT-related deficits.MethodsIn the Need for Sleep studies, 194 adolescents (age = 15–19 years) underwent two baseline nights of 9-h time-in-bed (TIB), followed by two cycles of weekday manipulation nights and weekend recovery nights (9-h TIB). They were allocated 9 h, 8 h, 6.5 h, or 5 h of TIB for nocturnal sleep on weekdays. Three additional groups with 5 h or 6.5 h TIB were given an afternoon nap opportunity (5 h + 1 h, 5 h + 1.5 h, and 6.5 h + 1.5 h). ToT effects were quantified by performance change from the first 2 min to the last 2 min in a 10-min Psychomotor Vigilance Task administered daily.ResultsThe 9 h and the 8 h groups showed comparable ToT effects that remained at baseline levels throughout the protocol. ToT-related deficits were greater among the 5 h and the 6.5 h groups, increased prominently in the second week of sleep restriction despite partial recuperation during the intervening recovery period and diverged between these two groups from the fifth sleep-restricted night. Daytime napping attenuated ToT effects when nocturnal sleep restriction was severe (i.e. 5-h TIB/night), and held steady at baseline levels for a milder dose of nocturnal sleep restriction when total TIB across 24 h was within the age-specific recommended sleep duration (i.e. 6.5 h + 1.5 h).ConclusionsReducing TIB beyond the recommended duration significantly increases ToT-associated vigilance impairment, particularly during recurrent periods of sleep restriction. Daytime napping is effective in ameliorating such decrement.Clinical Trial Registration, NCT02838095, and NCT03333512. NCT04044885相似文献
43.
Objective : To determine antibody levels to the Australian manufactured combined diphtheria, tetanus and pertussis (DTP) vaccine (Triple Antigen, CSL Ltd) in infante before and after their primary immunization course.
Methodology : Serosurvey (antibody prevalence study) in two groups: infants aged 5-9 weeks who had not received any immunizations ( n = 25), and infants aged 7-10 months who had received two ( n = 25) or three immunizations ( n = 57) with DTP, sampled from infants attending the Royal Children's Hospital, Melbourne, either as inpatients or outpatients between February and April 1993. The immunization history for each infant was determined from hospital records, the parent-held child health record, or the local council or family doctor who immunized the infant.
Results : Enzyme immunoassay (EIA) of antibodies to diphtheria and tetanus showed all infants to have adequate protective levels after two or three vaccinations (£0.01 IU/mL). All subjects who had received all three DTP vaccinations had detectable antibody to at least one pertussis antigen. Antibodies to the pertussis antigens filamentous haemagglutinin and pertussigen (pertussis toxin) were comparable to levels determined for whole cell pertussis vaccines used elsewhere in the world. EIA-determined antibodies to pertussis agglutinogen type 2 and agglutinogen type 3 showed substantially higher geometric mean titres when results for pre-immunization and post-immunization subjects were compared.
Conclusions : These data show that the Australian manufactured DTP vaccine has immunogenic properties similar to those of vaccines used elsewhere, and that antibody concentrations following immunization are at levels consistent with efficacy. 相似文献
Methodology : Serosurvey (antibody prevalence study) in two groups: infants aged 5-9 weeks who had not received any immunizations ( n = 25), and infants aged 7-10 months who had received two ( n = 25) or three immunizations ( n = 57) with DTP, sampled from infants attending the Royal Children's Hospital, Melbourne, either as inpatients or outpatients between February and April 1993. The immunization history for each infant was determined from hospital records, the parent-held child health record, or the local council or family doctor who immunized the infant.
Results : Enzyme immunoassay (EIA) of antibodies to diphtheria and tetanus showed all infants to have adequate protective levels after two or three vaccinations (£0.01 IU/mL). All subjects who had received all three DTP vaccinations had detectable antibody to at least one pertussis antigen. Antibodies to the pertussis antigens filamentous haemagglutinin and pertussigen (pertussis toxin) were comparable to levels determined for whole cell pertussis vaccines used elsewhere in the world. EIA-determined antibodies to pertussis agglutinogen type 2 and agglutinogen type 3 showed substantially higher geometric mean titres when results for pre-immunization and post-immunization subjects were compared.
Conclusions : These data show that the Australian manufactured DTP vaccine has immunogenic properties similar to those of vaccines used elsewhere, and that antibody concentrations following immunization are at levels consistent with efficacy. 相似文献
44.
TAŞ Beray Gelmez Özceylan Gökmen Öztürk Güzin Zeren Toprak Dilek 《Journal of community health》2021,46(4):777-785
Journal of Community Health - The purpose of this study was to evaluate family physicians’ job strain during the Covid-19 pandemic and determine the effective factors. The study was carried... 相似文献
45.
目的 :了解我国卫生应急人员对突发公共卫生事件风险评估的认知状况,从文化程度、职称情况、单位性质、单位级别等方面进行比较,为提高卫生应急人员风险评估的认识和能力提供依据。方法 :采用问卷调查的方法,对全国(大陆地区)31个省(自治区、直辖市)承担突发公共卫生事件应急处置的卫生应急工作人员进行调查。采用描述性分析和χ2检验对调查数据进行分析。结果 :我国卫生应急人员对风险评估概念熟悉程度较低,且不同学历、不同职称、不同工作年限、不同机构、不同层级之间的认知存在一定差异;对风险评估工作内容的认知也存在分歧。结论 :应加强风险评估培训,健全风险评估制度,以全面提高卫生应急人员对风险评估的认知水平。 相似文献
46.
目的探讨耳穴贴压治疗单纯性肥胖症的临床效应。方法应用耳穴贴压治疗单纯性肥胖症,观察治疗前后患者肥胖指标、血脂指标等的变化,评测耳穴贴压减肥的效果。结果各项指标在治疗前后差异均有显著性。结论耳穴贴压治疗单纯性肥胖,疗效确切,对患者各项生理指标有良性调节作用。 相似文献
47.
目的通过系统的生物信息学分析和实验验证,筛选黄热病毒的特异抗原片段,为免疫诊断试剂的研制奠定基础。方法分别利用DNAStar及ANTHEPROT软件对黄热病毒蛋白进行分析,参考亲水性、抗原性、可塑性、表面可及性及二级结构信息,对黄热病毒可能的共有及特异性抗原表位进行系统的预测分析,分析其在不同毒株中的保守性,并对预测得分值较高的抗原区域进行RT-PCR扩增,利用pMal-c2x原核表达系统进行原核表达,Western blot验证其免疫学反应原性,检测阳性抗原片段经亲和纯化后,包被ELISA微孔板,进一步验证其免疫学反应特异性及检测敏感性。结果其中27段抗原片段获高效表达,经Western blot筛选及ELISA进一步验证,原核表达抗原片段YFV22表现良好特异抗,可检测低至1∶12 800倍稀释的黄热病毒多克隆抗体,与所试其他参考病毒多克隆抗体无交叉反应。结论经系统筛选、验证,获黄热病毒特异性抗原片段1段,为其免疫学诊断试剂的研制奠定了基础。 相似文献
48.
淋巴靶向制剂——吸附抗癌药毫微粒活性炭的研究进展 总被引:12,自引:0,他引:12
目的介绍新型淋巴靶向制剂———吸附抗癌药毫微粒活性炭的研究进展。方法依据近年来的文献 ,对活性炭的制备工艺及体内外性质等方面进行了综述。结果活性炭具有很强的吸附功能 ,普通市售活性炭仅用作脱色、吸附热原与除味等。以微粒球磨机为粉碎器械 ,可加工制备粒径达1 0 0nm左右的纳米炭微粒 ,具有优越的淋巴趋向性。结论吸附抗癌药毫微粒活性炭在临床治疗癌症方面具有良好的运用前景 相似文献
49.
XPath是XML的基本查询语言,XPath查询最小化对于提高XML数据库的查询性能具有重要意义.但是,由于XPath查询最小化是一个coNP完备问题,大部分已有的算法局限于处理简单的XPath片段.本文从一个新的角度入手,综合考虑完备性和高效性,提出了一个新的查询最小化框架,与已有算法"面向结点",即逐个删除冗余结点的解决思路不同,本文提出"面向树模式"的方式,即通过计算树模式的自同态映射,寻找目标结点集最小的自同态映射,进而求解最小等价查询树的方法.该方法具有较高的效率,而且在--Z..情况下是完备的,尤其是可以进一步扩展到更复杂的XPath片段.本文以此框架为基础,给出一个可以计算复杂查询模式的算法. 相似文献