9 research outputs found

    基于分子间多量子相干的不均匀磁场下高分辨核磁共振方法的研究进展

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    高分辨核磁共振(nuclear magnetic resonance,NMR)通常需要高度均匀的强静磁场,然而在活体实验等情况下,样品的磁化率差异将不可避免地导致磁场的不均匀,并且这种不均匀性难以通过匀场等传统方法消除.最近,分子间多量子相干被利用来消除活体等样品中由磁场不均匀引起的谱线增宽以获得高分辨NMR谱.和其他高分辨NMR方法相比,分子间多量子相干方法具有独特的特征与优势,它能同时保留化学位移、峰的裂分模式、偶合常数和相对峰面积等信息.这些信息在传统的一维NMR中通常用于分析和表征分子结构.国家自然科学基金资助项目(批准号:20573084,10575085和10774125

    Relationship between the concentration of CHCl_3, CCl_4 and the ratio of micronucleus in an urban drinking water and its source water

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    为了解并改善饮用水质,在1991年第4季度至1993年第1季度,于某市水源水和水厂出厂水中采水样,每季度采集1次,每站位同时取两份,一份测定卤代烃的含量,一份用于处理蚕豆根尖并计数根尖细胞微核率。结果表明水厂出厂水中卤代烃含量比水源水的高,尤其是四氯化碳,各水厂出厂水中卤代烃的含量也有明显差异。发现水源水、水厂出厂水中四氯化碳含量与致突变有明显的相关性。ource water and outFlow of waterworks were sampled every quarter From the Fourth quarter 1991 to the First quarter 1993.Two samples were taken From each station, one For determination of CHCI_3, and CCI_4, and the other For treating of VICIA FADA root tip cell and counting the ratio of micronucleus of the root.It showed that the concentration of CHCI_3 and CCl_4 were higher in waterworks than in source water,especially For CCl_4.DiFFerences of chloro-carbons concentration were Found among waterworks.SigniFicant relationship was demonstrated between the concentration of CCl_4, and the mutagenesis

    Study of the Simulation of Marine Atmospheric Exposure with Lab Accelerated Test of Marine Coating Systems

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    通过两年海洋大气环境暴露试验、盐雾/紫外冷凝老化交替试验和氙灯老化试验,对比聚氨酯涂料、丙烯酸涂料涂层的色差和失光率,研究了3种试验对涂层表观性能的影响,发现紫外/冷凝老化加速试验对海洋大气暴露试验有很好的模拟性。The simulation of marine atmospheric exposure with lab accelerated test was studied.The lab accelerated test methods were UV-condensation and salt-fog alternant test and Xenon-Arc exposure test.The marine coating systems based on polyurethane and acrylic were compared in color difference and rate of losing gloss.The result showed that UV-condensation and salt-fog alternant test can better simulate the marine atmospheric environment than the Xenon-Arc exposure test

    Study on Correlation between Marine Environmental Test and Accelerated Tests in Laboratory for Ship Coatings——Coating Systems for Marine Atmosphere

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    采用光泽-色泽仪、涂膜粉化率测定仪、fdIr,SEM及AfM等现代测试分析手段,对海洋大气区7种常用舰船涂料体系在实际海洋环境暴露试验以及室内人工加速老化及腐蚀试验前后的涂层性能变化进行了对比分析,并结合厦门地区的气象环境谱探索了实验室加速试验与实际海洋大气暴露试验的相关性。Seven ship coating systems were exposed in marine atmospheric environment and accelerated weathering tests in lab.Some modern analyses,such as gloss and color measurement,coat chalk rating,precise thickness meter,FDIR,SEM,AFM were applied to characterize the properties of the coating systems.The results of performance change before and after exposure were compared.The weather environmental spectrum of Xiamen area was also combined for discussion of the correlation between marine environmental exposure tests and accelerated weathering tests in lab

    Aripiprazole versus other atypical antipsychotics for schizophrenia

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    BACKGROUND: In most western industrialised countries, second generation (atypical) antipsychotics are recommended as first line drug treatments for people with schizophrenia. In this review we specifically examine how the efficacy and tolerability of one such agent - aripiprazole - differs from that of other comparable second generation antipsychotics. OBJECTIVES: To evaluate the effects of aripiprazole compared with other atypical antipsychotics for people with schizophrenia and schizophrenia-like psychoses. SEARCH METHODS: We searched the Cochrane Schizophrenia Group Trials Register (November 2011), inspected references of all identified studies for further trials, and contacted relevant pharmaceutical companies, drug approval agencies and authors of trials for additional information. SELECTION CRITERIA: We included all randomised clinical trials (RCTs) comparing aripiprazole (oral) with oral and parenteral forms of amisulpride, clozapine, olanzapine, quetiapine, risperidone, sertindole, ziprasidone or zotepine for people with schizophrenia or schizophrenia-like psychoses. DATA COLLECTION AND ANALYSIS: We extracted data independently. For dichotomous data we calculated risk ratios (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. Where possible, we calculated illustrative comparative risks for primary outcomes. For continuous data, we calculated mean differences (MD), again based on a random-effects model. We assessed risk of bias for each included study. MAIN RESULTS: We included 12 trials involving 6389 patients. Aripiprazole was compared to olanzapine, risperidone and ziprasidone. All trials were sponsored by an interested drug manufacturer. The overall number of participants leaving studies early was 30% to 40%, limiting validity (no differences between groups).When compared with olanzapine no differences were apparent for global state (no clinically important change: n = 703, 1 RCT, RR short-term 1.00 95% CI 0.81 to 1.22; n = 317, 1 RCT, RR medium-term 1.08 95% CI 0.95 to 1.22) but mental state tended to favour olanzapine (n = 1360, 3 RCTs, MD total Positive and Negative Syndrome Scale (PANSS) 4.68 95% CI 2.21 to 7.16). There was no significant difference in extrapyramidal symptoms (n = 529, 2 RCTs, RR 0.99 95% CI 0.62 to 1.59) but fewer in the aripiprazole group had increased cholesterol levels (n = 223, 1 RCT, RR 0.32 95% CI 0.19 to 0.54) or weight gain of 7% or more of total body weight (n = 1095, 3 RCTs, RR 0.39 95% CI 0.28 to 0.54).When compared with risperidone, aripiprazole showed no advantage in terms of global state (n = 384, 2 RCTs, RR no important improvement 1.14 95% CI 0.81 to 1.60) or mental state (n = 372, 2 RCTs, MD total PANSS 1.50 95% CI -2.96 to 5.96).One study compared aripiprazole with ziprasidone (n = 247) and both the groups reported similar change in the global state (n = 247, 1 RCT, MD average change in Clinical Global Impression-Severity (CGI-S) score -0.03 95% CI -0.28 to 0.22) and mental state (n = 247, 1 RCT, MD change PANSS -3.00 95% CI -7.29 to 1.29).When compared with any one of several new generation antipsychotic drugs the aripiprazole group showed improvement in global state in energy (n = 523, 1 RCT, RR 0.69 95% CI 0.56 to 0.84), mood (n = 523, 1 RCT, RR 0.77 95% CI 0.65 to 0.92), negative symptoms (n = 523, 1 RCT, RR 0.82 95% CI 0.68 to 0.99), somnolence (n = 523, 1 RCT, RR 0.80 95% CI 0.69 to 0.93) and weight gain (n = 523, 1 RCT, RR 0.84 95% CI 0.76 to 0.94). Significantly more people given aripiprazole reported symptoms of nausea (n = 2881, 3 RCTs, RR 3.13 95% CI 2.12 to 4.61) but weight gain (7% or more of total body weight) was less common in people allocated aripiprazole (n = 330, 1 RCT, RR 0.35 95% CI 0.19 to 0.64). Aripiprazole may have value in aggression but data are limited. This will be the focus of another review. AUTHORS' CONCLUSIONS: Information on all comparisons are of limited quality, are incomplete and problematic to apply clinically. Aripiprazole is an antipsychotic drug with a variant but not absent adverse effect profile. Long-term data are sparse and there is considerable scope for another update of this review as new data emerges from the many Chinese studies as well as from ongoing larger, independent pragmatic trials
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