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31.
研究一株黄河三角洲滨海湿地来源的真菌Fusarium oxysporum RD-79的次级代谢产物及其生物活性。利用硅胶柱色谱、ODS柱色谱、半制备高效液相色谱等分离方法对该菌株发酵产物进行分离纯化,通过核磁共振(NMR)、质谱(MS)等方法,结合相关文献对比鉴定化合物结构;分别采用CCK8法和Griess法对化合物进行抗肿瘤活性和抗炎活性测试。从Fusarium oxysporum RD-79的发酵产物中分离得到8个单体化合物,分别为5-bμtyl-4-methoxy-6-methyl-2H-pyran-2-one(1)、甲醛甲苯(2)、delitpyroneD(3)、3-hydroxymethyl-6,8-dimethoxycoμmaarin(4)、5-[(1S,2S)-1,2-dihydroxybμtyl]-4-methoxy-6-methyl-2H-pyran-2-one(5)、setosphapyroneA(6)、5-(1-hydroxybμtyl)-4-methoxy-6-methyl-2H-pyran-2-one(7)、9-O-methylscytalol A(8)。化合物1~8均可不同程度抑制NO的产生;在浓度为100μg/mL下,化合物1~8均无抗肿瘤活性。 相似文献
32.
目的 了解唐山市PM2.5污染对唐山市市区人口造成的健康危害,估算由于PM2.5造成的健康经济损失。方法 收集唐山市2013—2017年基本社会人口资料与大气PM2.5浓度。选择循环系统疾病住院等为健康效应终点,选用适当的暴露-反应关系,采取疾病成本法与支付意愿法相结合的方法评估PM2.5造成的健康效应的经济损失。结果 2013—2017年PM2.5污染造成的经济损失呈现逐年下降的趋势,其中2013年最高,为6.57亿元,占当年GDP的0.27%,2017年最低,为2.97亿元,占当年GDP的0.13%。结论 唐山PM2.5污染造成的健康损失呈现逐年下降的趋势,但数字仍然非常可观,需要进一步加强对PM2.5污染的监控与治理。 相似文献
33.
气温作为全球性环境危险因素之一,能增加人群发病和死亡风险,造成健康经济损失。评估温度相关疾病负担对于制定及实施适应性政策具有重要意义。论文聚焦近年来全球各国温度相关疾病负担研究,梳理和评价相关研究指标、评估方法与现状,为温度相关疾病负担的评估及预估研究提出建议。 相似文献
34.
35.
Naohiro Ikeda Kenkichi FujiiMiko Sarada Hitoshi SaitoMasayoshi Kawabata Kiyoko NaruseKatsuyuki Yuki Hideaki NakagiriHiroshi Honda Yasushi TamakiNaohiro Nishiyama Toshio Kasamatsu 《Food and chemical toxicology》2012
Glycidol fatty acid esters (GEs) are found in refined edible oils. Safety concerns have been alleged due to the possible release of glycidol (G), an animal carcinogen. 相似文献
36.
2009年鄱阳湖生态经济区开发上升为国家战略,鄱阳湖生态经济区的发展成为江西实现中部崛起的重要举措。但值得关注的是,经济区生态系统的保护、环境问题的改善必须放在重要地位,必须认真分析开发过程中遇到的地表及尘土污染防治差额、水资源污染防治差额、执法效能差额、环境管理与监控差额等环境保护的成长上限问题。为此,笔者根据成长上限的消除原理,提出管理对策。 相似文献
37.
Bonnie L. Webster Oumar T. Diaw Mohmoudane M. Seye Djibril S. Faye J. Russell Stothard Jose C. Sousa-Figueiredo David Rollinson 《Acta tropica》2013
Following major water development schemes in the 1980s, schistosomiasis has become a serious parasitic disease of children living in the Senegal River Basin. Both urogenital (Schistosoma haematobium) and intestinal (Schistosoma mansoni) schistosomiasis can be highly prevalent in school-aged children, with many individuals infected with both parasites. In order to investigate the transmission and re-infection dynamics of both parasite species, single and mixed infection foci at three villages (Nder and Temeye; S. mansoni and S. haematobium foci and Guia; S. haematobium focus) were studied. In each focus infected children were identified and selected for a 12-month study involving two treatments with praziquantel (40 mg/kg) three weeks apart at the beginning of the study and again 6 months into the study. Urine and stool samples were examined for schistosome eggs before and at 6 weeks and 6 months after chemotherapy. Prevalence and intensity of infection were recorded for each child at each time point. Before treatment, in all three villages, the prevalence and intensity of infection was extremely high for both S. mansoni (79–100%) and S. haematobium (81–97%). With the first round of chemotherapy sufficient cure rates (CRs) of both species were achieved in all villages (38–96%) with high egg reduction rates (ERRs) (97–99%). The data show that high and rapid re-infection rates occur, especially for S. mansoni, within a six-month period following treatment. Re-infection must be highly linked to ecological and seasonal factors. The persistence of S. mansoni in Nder could raise concern as levels of infection intensity remain high (geometric mean intensity at baseline 653 epg changed to 705 epg at 12 months) after four rounds of chemotherapy. This phenomenon could be explained by extremely rapid re-infection dynamics or a sub-optimal efficacy of praziquantel against S. mansoni in this village. High intensities in mixed infections may influence disease epidemiology and control warranting further studies. The disease situation in the SRB must be monitored closely and new treatment regimes should be designed and implemented to control schistosomiasis in the school-age population. 相似文献
38.
Housing conditions can impact on physical and mental health through 4 interrelated dimensions: 1) the home (the emotional housing conditions), 2) the physical housing conditions, and 3) the physical environment, and 4) the social (community) environment of the neighborhood where the house is located. In Spain, the use of the construction market as an engine for economic growth and the promotion of private property as the main type of housing tenure has led to the use of housing as a speculative good instead of its being considered a first-necessity good. While Spain is the Organisation for Economic Co-operation and Development (OECD) country with the largest housing stock per inhabitant, this stock is highly underutilized, thus excluding the most deprived sector of the population from access to housing. The impact of the current economic crisis on housing has mainly been due to a reduction in household income, which has increased the number of families or persons struggling to cover their housing costs or being evicted. Evidence indicates that this type of problem has a negative impact on health, especially on mental health, but financial problems also make it difficult to meet other basic needs such as eating. There are several instruments to reduce the impact of the economic crisis, such as debt financing or deed of assignment in payment. In the long-term, the creation of a social housing stock should be promoted, as well as rental assistance mechanisms. 相似文献
39.
目的 对内毒素检测阳性的肺结核患者实施不同治疗策略,分析不同策略的成本-效果,为利用一清胶囊治疗革兰阴性菌(G)感染提供理论和经济学依据.方法 120例内毒素检测阳性的肺结核患者随机分为治疗组和对照组,治疗组同时接受一清胶囊联合常规的抗菌治疗,对照组仅进行常规的抗菌治疗.分别记录患者的CRP的复常时间、体温复常时间、内毒素转阴时间以及影像的感染情况改善程度进行成本-效果分析.结果 治疗组的CRP复常时间、体温复常时间和内毒素转阴时间均明显短于对照组.两组患者均未观察到空洞闭合,但治疗组47例患者的结核病灶有吸收好转(有效率78.3%);对照组33例患者的结核病灶有吸收好转(有效率55.0%),两组比较差异有统计学意义(x2=4.97,P<0.05).成本-效果分析表明对照组疗效较差且治疗成本明显偏高(P=0.013).结论 一清胶囊与常规抗菌治疗之间具有协同作用,能明显缩短病程和住院时间,两者联用成本效果更好,具有重要的经济价值. 相似文献
40.
Roberto Secades-Villa Gloria García-Fernández Elsa Peña-Suárez Olaya García-Rodríguez Emilio Sánchez-Hervás José Ramón Fernández-Hermida 《Journal of substance abuse treatment》2013
Contingency management (CM) has demonstrated its efficacy for treating cocaine dependence, but there is still some controversy with regard to its dissemination. Understanding how individual differences affect CM outcomes is important for detecting barriers to its dissemination. The aim of this study is to examine the impact of socioeconomic variables in cocaine-dependent outpatients on the effectiveness of CM in a community setting. Cocaine-dependent outpatients (N = 118) were randomized to community reinforcement approach (CRA) treatment or a CRA plus vouchers program. The impact of baseline economic variables, alone and in combination with treatment conditions, on abstinence and retention outcomes after 6 months of treatment was assessed. Results showed that income had no effect on retention or abstinence outcomes after 6 months of treatment in either treatment condition. The addition of a CM component was beneficial for individuals with any socioeconomic status. These results support the generalizability of CM strategies with patients of different socioeconomic status in community settings. 相似文献