• 【尼泊尔葡萄球菌菌株在不同来源的出现,包括人类临床资料。】 复制标题 收藏 收藏
    DOI:10.1111/j.1574-6968.2006.00408.x 复制DOI
    作者列表:Nováková D,Pantůcek R,Petrás P,Koukalová D,Sedlácek I
    BACKGROUND & AIMS: :Five isolates of coagulase-negative staphylococci were obtained from human urine, the gastrointestinal tract of squirrel monkeys, pig skin and from the environment. All key biochemical characteristics of the tested strains corresponded with the description of Staphylococcus xylosus species. However, partial 16S rRNA gene sequences obtained from analysed strains corresponded with those of Staphylococcus nepalensis reference strains, except for two strains which differed in one residue. Ribotyping with EcoRI and HindIII restriction enzymes, whole cell protein profile analysis performed by SDS-PAGE and SmaI macrorestriction analysis were used for more precise characterization and identification of the analysed strains. Obtained results showed that EcoRI and HindIII ribotyping and whole cell protein fingerprinting are suitable and reliable methods for the differentiation of S. nepalensis strains from the other novobiocin resistant staphylococci, whereas macrorestriction analysis was found to be a good tool for strain typing. The isolation of S. nepalensis is sporadic, and according to our best knowledge this study is the first report of the occurrence of this species in human clinical material as well as in other sources.
    背景与目标: :从人尿,松鼠的胃肠道,猪皮和环境中获得了五种凝固酶阴性葡萄球菌的分离株。被测菌株的所有关键生化特征均与葡萄球菌属物种的描述相对应。但是,从分析菌株获得的部分16S rRNA基因序列与尼泊尔葡萄球菌参考菌株相对应,除了两个菌株在一个残基上有所不同。使用EcoRI和HindIII限制性内切酶进行核糖体分型,通过SDS-PAGE和SmaI宏观限制性分析进行的全细胞蛋白质谱分析可用于更精确地表征和鉴定所分析的菌株。所得结果表明,EcoRI和HindIII核糖分型和全细胞蛋白质指纹图谱是区分尼泊尔链球菌菌株和其他对新霉素耐药的葡萄球菌的可靠方法,而宏观限制性分析被认为是很好的菌株分型工具。尼泊尔链球菌的分离是零星的,根据我们的最佳知识,这项研究是人类临床材料以及其他来源中该物种出现的第一份报告。
  • 【具有维生素B12代谢的cblJ先天性错误的非典型患者的症状较晚发作:外显子组测序揭示了诊断和新突变。】 复制标题 收藏 收藏
    DOI:10.1016/j.ymgme.2012.10.005 复制DOI
    作者列表:Kim JC,Lee NC,Hwu PW,Chien YH,Fahiminiya S,Majewski J,Watkins D,Rosenblatt DS
    BACKGROUND & AIMS: :Inborn errors of vitamin B(12) (cobalamin) metabolism are characterized by decreased production of active cobalamin cofactors and subsequent deficiencies in the activities of methionine synthase and methylmalonyl-CoA mutase. With the recent discovery of the cblJ defect in two patients with phenotypes mimicking the cblF defect, there are nine genes known to be involved in cobalamin metabolism. The new defect is caused by mutations in the ABCD4 gene, encoding an ABC transporter. At the moment, there is no clear distinction between the cblJ and cblF defects either clinically or biochemically, and both defects result in blocks in the transport of cobalamin from the lysosome to the cytoplasm. A patient was diagnosed with hyperhomocysteinemia and methylmalonic aciduria at the age of 8 years. Incorporations of both [(14)C]propionate and [(14)C]methyltetrahydrofolate in cultured fibroblasts were within reference ranges and thus too high to allow for complementation analysis. We observed decreased synthesis of both adenosylcobalamin and methylcobalamin and accumulation of unmetabolized cyanocobalamin. Exome sequencing was performed to identify causative mutation(s) and Sanger re-sequencing was performed to validate segregation of mutation in the family. By this approach, a homozygous mutation, c.423C>G, in the ABCD4 gene was identified. Here, we report the successful application of exome sequencing for diagnosis of a rare inborn error of vitamin B(12) metabolism in a patient whose unusual presentation precluded diagnosis using standard biochemical and genetic approaches. The patient represents only the third known patient with the cblJ disorder.
    背景与目标: :维生素B(12)(钴胺素)代谢的先天性错误的特征在于活性钴胺素辅因子的产生减少以及蛋氨酸合酶和甲基丙二酰辅酶A突变酶的活性随后不足。随着最近在两名模仿cblF缺陷的表型患者中发现cblJ缺陷,已知有9个基因与钴胺素代谢有关。新的缺陷是由编码ABC转运蛋白的ABCD4基因突变引起的。目前,在临床或生化方面,cblJ和cblF缺陷之间尚无明确区分,并且两种缺陷均导致钴胺素从溶酶体到细胞质的转运受阻。一名患者在8岁时被诊断出患有高同型半胱氨酸血症和甲基丙二酸尿症。 [(14)C]丙酸酯和[(14)C]甲基四氢叶酸在培养的成纤维细胞中的掺入均在参考范围内,因此含量过高,无法进行互补分析。我们观察到腺苷钴胺素和甲基钴胺素的合成减少以及未代谢的氰钴胺素的积累。进行了外显子组测序以鉴定致病突变,并进行了桑格重测序以验证家族中突变的分离。通过这种方法,鉴定出ABCD4基因中的纯合突变,即c.423C> G。在这里,我们报告外显子组测序在维生素B(12)代谢的罕见先天性错误的诊断中成功应用,该患者的异常表现排除了使用标准生化和遗传方法进行诊断的可能性。该患者仅代表第三位已知的cblJ疾病患者。
  • 【人为和自然资源对大气甲烷变化的贡献。】 复制标题 收藏 收藏
    DOI:10.1038/nature05132 复制DOI
    作者列表:Bousquet P,Ciais P,Miller JB,Dlugokencky EJ,Hauglustaine DA,Prigent C,Van der Werf GR,Peylin P,Brunke EG,Carouge C,Langenfelds RL,Lathière J,Papa F,Ramonet M,Schmidt M,Steele LP,Tyler SC,White J
    BACKGROUND & AIMS: :Methane is an important greenhouse gas, and its atmospheric concentration has nearly tripled since pre-industrial times. The growth rate of atmospheric methane is determined by the balance between surface emissions and photochemical destruction by the hydroxyl radical, the major atmospheric oxidant. Remarkably, this growth rate has decreased markedly since the early 1990s, and the level of methane has remained relatively constant since 1999, leading to a downward revision of its projected influence on global temperatures. Large fluctuations in the growth rate of atmospheric methane are also observed from one year to the next, but their causes remain uncertain. Here we quantify the processes that controlled variations in methane emissions between 1984 and 2003 using an inversion model of atmospheric transport and chemistry. Our results indicate that wetland emissions dominated the inter-annual variability of methane sources, whereas fire emissions played a smaller role, except during the 1997-1998 El Niño event. These top-down estimates of changes in wetland and fire emissions are in good agreement with independent estimates based on remote sensing information and biogeochemical models. On longer timescales, our results show that the decrease in atmospheric methane growth during the 1990s was caused by a decline in anthropogenic emissions. Since 1999, however, they indicate that anthropogenic emissions of methane have risen again. The effect of this increase on the growth rate of atmospheric methane has been masked by a coincident decrease in wetland emissions, but atmospheric methane levels may increase in the near future if wetland emissions return to their mean 1990s levels.
    背景与目标: :甲烷是一种重要的温室气体,自工业化前以来,其大气浓度几乎增加了两倍。大气甲烷的增长率取决于表面排放与主要大气氧化剂羟基自由基对光化学的破坏之间的平衡。值得注意的是,自1990年代初以来,这一增长率已明显下降,而甲烷的水平自1999年以来一直保持相对稳定,从而导致其对全球气温的预计影响向下修正。从一年到下一年,大气中甲烷的增长率也出现了较大的波动,但其原因仍然不确定。在这里,我们使用大气传输和化学反演模型对控制1984年至2003年甲烷排放量变化的过程进行了量化。我们的结果表明,除1997-1998年厄尔尼诺事件外,甲烷排放源的年际变化主要是湿地排放,而火灾排放的作用较小。这些对湿地和火灾排放变化的自上而下的估算与基于遥感信息和生物地球化学模型的独立估算非常吻合。在更长的时间尺度上,我们的结果表明,1990年代期间大气甲烷增长的下降是由于人为排放量的下降引起的。但是,自1999年以来,它们表明人为排放的甲烷再次增加。湿地排放量的同时减少掩盖了这种增加对大气中甲烷增长率的影响,但是如果湿地排放量恢复到1990年代的平均水平,那么大气中的甲烷水平在不久的将来可能会增加。
  • 【碳源对生物电化学系统中脱氮性能的影响。】 复制标题 收藏 收藏
    DOI:10.1016/j.biortech.2012.11.004 复制DOI
    作者列表:Feng H,Huang B,Zou Y,Li N,Wang M,Yin J,Cong Y,Shen D
    BACKGROUND & AIMS: :In order to ascertain the effects of different carbon sources (methanol, glucose, starch and NaHCO(3)) on denitrification in BESs, the experiment was conducted in a constant current, 3.5 of chemical oxygen demand to nitrate ratio in a greenhouse. Among the four carbon sources investigated in BESs, NaHCO(3) showed the highest nitrite accumulation and the ratio of soluble microbial products to soluble chemical oxygen demand (SMP/SCOD) with a value of 3.68 ± 0.68 mg/L and 94%, respectively. And the addition of organic substrates could reduce SMP production and enhance the denitrification process. In the constant voltage experiment, it was observed that the organics could be used by microbes to generate electrons at the anode. And a maximal current value of 11.0 mA in the BESs fed with starch indicated that the complex carbon source was easier to be used by microorganisms to generate electricity than the simple carbon source.
    背景与目标: :为了确定不同碳源(甲醇,葡萄糖,淀粉和NaHCO(3))对BES中反硝化的影响,该实验在恒定电流下进行,该温室中化学需氧量与硝酸盐的比率为3.5。在BES中研究的四种碳源中,NaHCO(3)表现出最高的亚硝酸盐积累和可溶性微生物产物与可溶性化学需氧量(SMP / SCOD)的比率,分别为3.68±0.68 mg / L和94% 。并且添加有机底物可以减少SMP的产生并增强反硝化过程。在恒压实验中,观察到微生物可以将有机物用于在阳极产生电子。淀粉喂养的BES中的最大电流值为11.0 mA,这表明与简单碳源相比,微生物更容易使用复杂的碳源发电。
  • 【实时超声与计算机断层扫描的图像融合:影响肝脏局灶性病变的配准误差和运动的因素。】 复制标题 收藏 收藏
    DOI:10.1016/j.ultrasmedbio.2017.01.027 复制DOI
    作者列表:Lee MW,Park HJ,Kang TW,Ryu J,Bang WC,Lee B,Lee ES,Choi BI
    BACKGROUND & AIMS: :Factors affecting the registration error (RE) and motion of focal hepatic lesions (FHLs) in image fusion of real-time ultrasonography (US) with computed tomography (CT) images were prospectively assessed by focusing on respiratory movement and FHL location. Real-time US and pre-acquired CT images at end-inspiration were fused with FHLs for 103 patients. Three-dimensional US data containing FHLs were obtained during end-inspiratory/expiratory phases. Multivariate analysis revealed that diaphragm motion (p < 0.001), chronic liver disease (p = 0.02) and the absolute difference in distance between the FHL and the central portal vein (CPV) during respiration (p = 0.03) were the independent factors that revealed the maximum effect on RE. In contrast, diaphragm motion (p < 0.001) and distance between the FHL and CPV at inspiration (p = 0.036) revealed the maximum effect on FHL motion. In conclusion, RE and FHL motion are affected by the degree of respiratory movement and the location of the FHL. Therefore, image fusion with CT images should be used with caution if the degree of respiratory motion is significant or if the FHL is located at the periphery of the liver.
    背景与目标: :前瞻性评估了实时超声检查(US)与计算机断层扫描(CT)图像融合中影响配准误差(RE)和局灶性肝病灶(FHLs)运动的因素,重点在于呼吸运动和FHL位置。吸气时将实时美国超声和预先采集的CT图像与FHL融合在一起,治疗103例患者。在吸气/呼气末期获得包含FHL的三维US数据。多因素分析表明,呼吸过程中diaphragm肌运动(p <0.001),慢性肝病(p = 0.02)和FHL与门静脉中央静脉(CPV)之间的绝对距离差(p = 0.03)是揭示这些因素的独立因素。对RE的最大影响。相反,隔膜运动(p <0.001)和吸气时FHL与CPV之间的距离(p = 0.036)揭示了对FHL运动的最大影响。总之,RE和FHL运动受呼吸运动程度和FHL位置的影响。因此,如果呼吸运动的程度很明显或者FHL位于肝脏的周围,则应谨慎使用CT图像融合。
  • 【重症监护病房主要噪声源的行为观察。】 复制标题 收藏 收藏
    DOI:10.1016/j.jcrc.2013.06.006 复制DOI
    作者列表:Xie H,Kang J,Mills GH
    BACKGROUND & AIMS: PURPOSE:This study aimed to investigate the behavior patterns of typical noise sources in critical care wards and relate their patterns to health care environment in which the sources adapt themselves in several different forms. METHODS:An effective observation approach was designed for noise behavior in the critical care environment. Five descriptors have been identified for the behavior observations, namely, interval, frequency, duration, perceived loudness, and location. Both the single-bed and the multiple-bed wards at the selected Critical Care Department were randomly observed for 3 inconsecutive nights, from 11:30 pm to 7:00 am the following morning. The Matlab distribution fitting tool was applied afterward to plot several types of distributions and estimate the corresponding parameters. RESULTS:The lognormal distribution was considered the most appropriate statistical distribution for noise behaviors in terms of the interval and duration patterns. The turning of patients by staff was closely related to the increasing occurrences of noises. Among the observed noises, talking was identified with the highest frequency, shortest intervals, and the longest durations, followed by monitor alarms. The perceived loudness of talking in the nighttime wards was classified into 3 levels (raised, normal, and low). Most people engaged in verbal communication in the single-bed wards that occurred around the Entrance Zone, whereas talking in the multiple-bed wards was more likely to be situated in the Staff Work Zone. As expected, more occurrences of noises along with longer duration were observed in multiple-bed wards rather than single-bed wards. "Monitor plus ventilator alarms" was the most commonly observed combination of multiple noises.
    背景与目标: 目的:本研究旨在调查重症监护病房中典型噪声源的行为模式,并将其模式与卫生保健环境相关联,在该环境中,噪声源以几种不同形式进行适应。
    方法:针对重症监护环境中的噪声行为设计了一种有效的观察方法。已经为行为观察确定了五个描述符,即间隔,频率,持续时间,感知的响度和位置。从所选的重症监护室的单床病房和多床病房在晚上11:30 pm至第二天早上7:00连续3个连续晚上。之后使用Matlab分布拟合工具绘制几种类型的分布并估计相应的参数。
    结果:就间隔和持续时间模式而言,对数正态分布被认为是最适合噪声行为的统计分布。医务人员的转机与噪声的发生率增加密切相关。在观察到的噪声中,说话被确定为频率最高,间隔最短,持续时间最长,其次是监视器警报。夜间病房中说话的感觉响度分为3级(提高,正常和低)。大多数人在入口区附近的单人病房中进行口头交流,而在多人病房中交谈的人更可能位于员工工作区。正如预期的那样,在多床病房而不是单床病房中观察到了更多的噪音并伴有更长的持续时间。 “监视器加呼吸机警报”是多种噪声中最常见的组合。
  • 【尿布中粪便的存在是使用节肢动物发育率估算死后间隔的潜在错误来源。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Goff ML,Charbonneau S,Sullivan W
    BACKGROUND & AIMS: :Second instar larvae of the fly Chrysomya megacephala (Diptera, Calliphoridae) were recovered from the diapers of a 16-month-old child abandoned by her mother on Oahu, Hawaii. The development of these larvae indicated a minimum period of 23.5 h of exposure prior to discovery of the child. Larvae of this species of fly are not normally associated with living tissues in Hawaii, but rather with feces and remains during the early stages of decomposition. Had the child in this case died and data not been provided detailing the site of infestation, the postmortem interval estimated would have been significantly longer than was actually the case, because of the development of the larvae inside the diapers of the living child. The need for caution in cases involving deaths of infants, the elderly, and individuals not capable of caring for themselves is stressed.
    背景与目标: :蝇蝇(Chrysomya megacephala,Diptera,Calliphoridae)的第二龄幼虫是从一个被母亲遗弃在夏威夷瓦胡岛的16个月大婴儿的尿布中回收的。这些幼虫的发育表明在发现孩子之前最短的暴露时间为23.5小时。这种蝇类的幼虫通常与夏威夷的生物组织无关,而与分解初期的粪便和残骸有关。如果在这种情况下该儿童死亡,并且未提供详细的侵染地点的数据,则估计的死后间隔时间将比实际情况长得多,这是因为活着的儿童尿布内的幼虫发育所致。强调在涉及婴儿,老人和无能力照顾自己的人的死亡的情况下需要谨慎。
  • 【位于身体附近10 cm处的点伽马射线源的等效有效剂量。】 复制标题 收藏 收藏
    DOI:10.1097/01.HP.0000202237.19610.20 复制DOI
    作者列表:Xu XG,Bushart S,Anderson R
    BACKGROUND & AIMS: :The key component in the so-called EPRI effective dose equivalent (EDE) methodology is an algorithm that utilizes two dosimeters (instead of multiple dosimeters) to predict the EDE for external photon exposures. The exposure scenarios that were previously studied in deriving the algorithm include parallel photon beams and point sources 33 cm from the body surface. The motivation for this study was the need to investigate source locations within 33 cm from the body so the method is more widely applicable. The ORNL stylized mathematical human phantoms and the MCNP code were used to calculate organ doses in this study. This paper presents the EDE data for point gamma sources at 0.3, 1.0, and 1.5 MeV, respectively, which are located at 10 cm from the surface of the body. The results and analyses show that the locations ranging from the overhead to the foot have resulted in conservative ratios except for two general regions near the front upper thigh and directly overhead. If all locations considered in this study were averaged for each photon energy, the overall ratio is on the conservative side. These data suggest that the EPRI EDE methodology is still valid for sources located 10 cm from the body, although the chance for resulting in a non-conservative estimate of the EDE has increased in comparison with the sources located at 30 cm from the body. Finally, this paper provides recommendations on how to apply the EPRI EDE methodology.
    背景与目标: :所谓的EPRI有效剂量当量(EDE)方法中的关键组件是一种算法,该算法利用两个剂量计(而不是多个剂量计)来预测外部光子暴露的EDE。先前在推导算法时曾研究过的曝光场景包括平行光子束和距体表33 cm的点光源。这项研究的动机是需要调查距人体33厘米以内的放射源位置,因此该方法更广泛地适用。在本研究中,使用了ORNL程式化的数学人体模型和MCNP代码来计算器官剂量。本文介绍了分别位于距人体表面10 cm处的0.3 MeV,1.0 MeV和1.5 MeV的点伽马源的EDE数据。结果和分析表明,从头顶到脚的位置范围导致了保守的比率,除了大腿前上方和直接头顶附近的两个一般区域。如果在本研究中考虑的所有位置均针对每种光子能量求平均值,则总体比率处于保守的一面。这些数据表明,EPRI EDE方法对于距离人体10厘米处的放射源仍然有效,尽管与位于人体30厘米处的放射源相比,导致EDE非保守估计的机会有所增加。最后,本文提供了有关如何应用EPRI EDE方法的建议。
  • 【临床流行病学的现有数据来源:丹麦医学遗传疾病研究注册机构。】 复制标题 收藏 收藏
    DOI:10.2147/CLEP.S45228 复制DOI
    作者列表:Nguyen-Nielsen M,Svensson E,Vogel I,Ehrenstein V,Sunde L
    BACKGROUND & AIMS: :Denmark has an extensive collection of national and regional medical registries. There are many advantages to registry-based research when investigating genetic diseases which, due to their rarity, can be difficult to identify. In this study, we aimed to provide an updated overview of Danish registries for medical genetic conditions and describe how data linkage across registries can be used to collect data on genetic diseases at the individual level and at the family level. We present a list of medical genetic registries in Denmark at the national level, data sources from the departments of clinical genetics and other specialized centers, and project-specific data sources. We also summarize key general registries, such as the Danish National Registry of Patients, the Danish Medical Birth Registry, and the Civil Registration System, which are renowned for their comprehensive and high quality data, and are useful supplemental data sources for genetic epidemiology research. We describe the potential for data linkage across multiple registries, which allows for access to medical histories with follow-up time spanning birth to death. Finally, we provide a brief introduction to the Danish epidemiological research setting and legalities related to data access. The Danish collection of medical registries is a valuable resource for genetic epidemiology research.
    背景与目标: :丹麦拥有大量的国家和地区医疗注册机构。基于注册表的研究在调查遗传疾病时有许多优势,由于其稀有性,可能难以识别。在这项研究中,我们旨在提供有关医学遗传状况的丹麦注册管理机构的最新概述,并描述如何将各个注册管理机构之间的数据链接用于收集个人和家庭一级的遗传疾病数据。我们提供了丹麦国家一级的医学遗传注册机构清单,来自临床遗传学部门和其他专门中心的数据来源,以及针对特定项目的数据来源。我们还总结了关键的一般注册机构,例如丹麦国家患者注册中心,丹麦医疗出生注册中心和民事注册系统,这些机构以其全面而高质量的数据而著称,并且是遗传流行病学研究的有用补充数据源。我们描述了跨多个注册表的数据链接的潜力,这允许访问具有从出生到死亡的后续时间的医疗历史记录。最后,我们简要介绍了丹麦的流行病学研究背景以及与数据访问相关的合法性。丹麦医学注册资料库是遗传流行病学研究的宝贵资源。
  • 【定量偏差分析可估计自我报告的体育活动与结直肠癌风险之间相关性的与测量误差相关的衰减。】 复制标题 收藏 收藏
    DOI:10.1093/ije/dyz209 复制DOI
    作者列表:Mahmood S,Nguyen NH,Bassett JK,MacInnis RJ,Karahalios A,Owen N,Bruinsma FJ,Milne RL,Giles GG,English DR,Lynch BM
    BACKGROUND & AIMS: BACKGROUND:Self-reported physical activity is inaccurate, yet few investigators attempt to adjust for measurement error when estimating risks for health outcomes. We estimated what the association between self-reported physical activity and colorectal cancer risk would be if physical activity had been assessed using accelerometry instead. METHODS:We conducted a validation study in which 235 Australian adults completed a telephone-administered International Physical Activity Questionnaire (IPAQ), and wore an accelerometer (Actigraph GT3X+) for 7 days. Using accelerometer-assessed physical activity as the criterion measure, we calculated validity coefficients and attenuation factors using a structural equation model adjusted for age, sex, education and body mass index. We then used a regression calibration approach to apply the attenuation factors to data from the Melbourne Collaborative Cohort Study (MCCS) to compute bias-adjusted hazard ratios (HR) and 95% confidence intervals (CI). RESULTS:Average daily minutes of physical activity from the short form of the International Physical Activity Questionnaire (IPAQ-short) were substantially higher than accelerometer-measured duration (55 versus 32 min). The validity coefficient (0.32; 95% CI: 0.20, 0.43) and attenuation factor (0.20; 95% CI: 0.12, 0.28) were low. The HRs for colorectal cancer risk for high (75th percentile; 411 min/week) versus low (25th percentile; 62 min/week) levels of self-reported physical activity were 0.95 (95% CI: 0.87, 1.05) before and 0.78 (95% CI: 0.47, 1.28) after bias adjustment. CONCLUSIONS:Over-estimation of physical activity by the IPAQ-short substantially attenuates the association between physical activity and colorectal cancer risk, suggesting that the protective effect of physical activity has been previously underestimated.
    背景与目标: 背景:自我报告的体育锻炼不准确,但是很少有研究者在估计健康后果的风险时尝试调整测量误差。我们估算了如果使用加速度计评估了身体活动,那么自我报告的身体活动与结直肠癌风险之间的关联将是什么。
    方法:我们进行了一项验证研究,其中235名澳大利亚成年人完成了电话管理的国际体育锻炼问卷(IPAQ),并佩戴了加速度计(Actigraph GT3X)7天。以加速度计评估的身体活动作为标准量度,我们使用针对年龄,性别,教育程度和体重指数调整的结构方程模型,计算了有效性系数和衰减因子。然后,我们使用了回归校准方法,将衰减因子应用于来自墨尔本合作队列研究(MCCS)的数据,以计算偏差调整后的危险比(HR)和95%置信区间(CI)。
    结果:简短的国际体力活动问卷(IPAQ-short)每天的体力活动分钟数明显高于加速度计测量的持续时间(55分钟对32分钟)。有效性系数(0.32; 95%CI:0.20,0.43)和衰减系数(0.20; 95%CI:0.12,0.28)低。自我报告的身体活动水平高(75%,411 min /周)与低(25th%; 62 min /周)的大肠癌风险的HR为之前的0.95(95%CI:0.87,1.05)和0.78( 95%CI:0.47,1.28)。
    结论:IPAQ-short对体育活动的过高估计大大削弱了体育活动与结直肠癌风险之间的关联,这表明体育活动的保护作用以前被低估了。
  • 【表没食子儿茶素(EGC)酯是抗氧化剂的潜在来源。】 复制标题 收藏 收藏
    DOI:10.1016/j.foodchem.2019.125609 复制DOI
    作者列表:Ambigaipalan P,Oh WY,Shahidi F
    BACKGROUND & AIMS: :Epigallocatechin (EGC) was acylated with selected fatty acids, namely propionic acid [C3:0], caprylic acid [C8:0], lauric acid [C12:0], stearic acid [C18:0]) and docosahexaenoic acid (DHA)[C22:6n-3] in order to increase its lipophilicity. Monoesters were identified as the predominant products (~40%) followed by diesters (~33%), triesters (~9%) and trace amounts of tetra- and pentaesters. 1H NMR, 13C NMR and HPLC-DAD-MS were used to elucidate the acylation sites and structures of new EGC esters. According to the HPLC-MS analysis of the caprylate esters, EGC-4'-O-caprylate (27%), EGC-3'-O-caprylate or EGC-5'-O-caprylate (12%) and EGC-3',5'-O-dicaprylate (16%) were the major compounds generated upon the acylation reaction of EGC. The acylation significantly increased the lipophilicity of EGC. In addition, EGC and its esters showed radical scavenging activities against DPPH radical and ABTS radical cation. Therefore, EGC esters could serve as potential sources of antioxidants for application in both hydrophilic and lipophilic media.
    背景与目标: :Epigallocatechin(EGC)被选定的脂肪酸酰化,即丙酸[C3:0],辛酸[C8:0],月桂酸[C12:0],硬脂酸[C18:0])和二十二碳六烯酸(DHA) )[C22:6n-3],以增加其亲脂性。单酯被确定为主要产物(约40%),其次是二酯(约33%),三酯(约9%)和痕量的四酯和五酯。 1 H NMR,13 C NMR和HPLC-DAD-MS用于阐明新EGC酯的酰化位点和结构。根据辛酸酯的HPLC-MS分析,EGC-4'-O-辛酸酯(27%),EGC-3'-O-辛酸酯或EGC-5'-O-辛酸酯(12%)和EGC-3 ',5'-O-二辛酸酯(16%)是EGC酰化反应生成的主要化合物。酰化显着增加了EGC的亲脂性。另外,EGC及其酯显示出对DPPH自由基和ABTS自由基阳离子的自由基清除活性。因此,EGC酯可作为潜在的抗氧化剂来源,用于亲水性和亲脂性介质。
  • 【用于检测重金属污染源的苔藓和表层土壤分析:多变量和富集因子分析。】 复制标题 收藏 收藏
    DOI:10.1007/s10661-008-0543-8 复制DOI
    作者列表:Dragović S,Mihailović N
    BACKGROUND & AIMS: :In order to assess the contribution of emission sources to the pollution of areas remote from industrial facilities, a combined approach of enrichment factor analysis and multivariate statistics was used for detecting the origin of heavy metal pollution in the Zlatibor ecosystem, in Serbia. Samples of moss (Pleurozium schreberi, Hylocomium splendens, Scleropodium purum, Hypnum cupressiforme and Thuidum delicatulum) and of topsoil (0-5 cm) were collected in 2005. The concentrations of seven heavy metals (Cd, Cr, Cu, Mn, Ni, Pb and Zn) were determined in moss and soil samples by atomic absorption spectrometry. The results obtained by enrichment factor analysis and two multivariate statistical methods, principal component analysis and cluster analysis, enabled discrimination of the lithologic and anthropogenic sources of heavy metals in the mosses. Enrichment factors, calculated to evaluate the contribution to the metal content in moss from anthropogenic sources, revealed pollution of the investigated area by Cd and Pb, originating from long-range transport and fossil fuel burning.
    背景与目标: :为了评估排放源对远离工业设施的地区的污染的贡献,采用了富集因子分析和多元统计相结合的方法来检测塞尔维亚Zlatibor生态系统中的重金属污染来源。 2005年收集了苔藓(schleberi菌,纤毛假单胞菌,紫毛菌,Hypnum cupressiforme和Thuidum delicatulum)和表土(0-5厘米)的样品。七种重金属(Cd,Cr,Cu,Mn,Ni,通过原子吸收光谱法测定苔藓和土壤样品中的Pb和Zn)。通过富集因子分析和两种多元统计方法(主成分分析和聚类分析)获得的结果可以区分苔藓中重金属的岩性和人为来源。计算出的富集因子用于评估人为来源对苔藓中金属含量的贡献,该因子表明Cd和Pb污染了被调查区域,这是由于远距离运输和化石燃料燃烧所致。
  • 【使用工具变量和纵向数据对具有两个通过误差测量的预测变量及其相互作用的模型进行回归校准。】 复制标题 收藏 收藏
    DOI:10.1002/sim.5904 复制DOI
    作者列表:Strand M,Sillau S,Grunwald GK,Rabinovitch N
    BACKGROUND & AIMS: :Regression calibration provides a way to obtain unbiased estimators of fixed effects in regression models when one or more predictors are measured with error. Recent development of measurement error methods has focused on models that include interaction terms between measured-with-error predictors, and separately, methods for estimation in models that account for correlated data. In this work, we derive explicit and novel forms of regression calibration estimators and associated asymptotic variances for longitudinal models that include interaction terms, when data from instrumental and unbiased surrogate variables are available but not the actual predictors of interest. The longitudinal data are fit using linear mixed models that contain random intercepts and account for serial correlation and unequally spaced observations. The motivating application involves a longitudinal study of exposure to two pollutants (predictors) - outdoor fine particulate matter and cigarette smoke - and their association in interactive form with levels of a biomarker of inflammation, leukotriene E4 (LTE 4 , outcome) in asthmatic children. Because the exposure concentrations could not be directly observed, we used measurements from a fixed outdoor monitor and urinary cotinine concentrations as instrumental variables, and we used concentrations of fine ambient particulate matter and cigarette smoke measured with error by personal monitors as unbiased surrogate variables. We applied the derived regression calibration methods to estimate coefficients of the unobserved predictors and their interaction, allowing for direct comparison of toxicity of the different pollutants. We used simulations to verify accuracy of inferential methods based on asymptotic theory.
    背景与目标: :回归校准提供了一种方法,当一个或多个预测变量进行误差测量时,可以获取回归模型中固定效应的无偏估计。测量误差方法的最新发展集中在模型上,该模型包括带误差的预测变量之间的交互项,以及分别用于解释相关数据的模型中的估计方法。在这项工作中,当有工具和无偏代理变量的数据可用,但实际感兴趣的预测变量不可用时,我们得出包含交互项的纵向模型的显式和新颖形式的回归校准估计量和相关的渐近方差。使用线性混合模型拟合纵向数据,该模型包含随机截距,并考虑了序列相关性和不等间隔的观测值。这项激励性应用涉及对哮喘儿童中两种污染物(预测因子)-室外细颗粒物和香烟烟雾-的暴露以及它们与炎症生物标志物白三烯E4(LTE 4,结局)水平的相互作用形式的关联的纵向研究。由于无法直接观察到暴露浓度,因此我们使用固定的室外监护仪的测量值和尿中可替宁的浓度作为仪器变量,我们使用个人监护仪错误测量的环境细颗粒物和香烟烟雾的浓度作为无偏倚的替代变量。我们应用派生的回归校准方法来估计未观察到的预测因子及其相互作用的系数,从而可以直接比较不同污染物的毒性。我们使用仿真来验证基于渐近理论的推论方法的准确性。
  • 【自我报告的抗癫痫药物的依从性及其与药物错误知觉的关系。】 复制标题 收藏 收藏
    DOI:10.1016/j.yebeh.2019.106896 复制DOI
    作者列表:Banks J,Varley J,Fitzsimons M,Doherty CP
    BACKGROUND & AIMS: :Although 70% of people with epilepsy (PWE) achieve seizure freedom following an appropriate antiepileptic drug (AED) regime, evidence suggests that adherence to AEDs by PWE is suboptimal. Nonadherence to AEDs is associated with increased morbidity, mortality, emergency department visits, and hospitalizations, with reduced adherence also correlating to a lower quality of life, decreased productivity, and loss of employment. Furthermore, research indicates that medication errors which are widespread in chronic disease are less well studied in epilepsy but are likely also to contribute to avoidable disease morbidity and mortality. The goals of this project were to determine rates of medication adherence by self-reported questionnaire and its links to perceived medication error in a cohort of PWE attending a general epilepsy outpatient clinic. Following a plan-do-study-act cycle, it was found that the most appropriate methodology for conducting was in the form of a bespoke 9-item self-administered questionnaire. One hundred eighty-six PWE completed a nine-question questionnaire asking patients about their own medication adherence habits and their perception that they were previously exposed to medication error. This study found that 41% of respondents reported suboptimal adherence to AED therapy, while 28.5% of respondents self-reported that they unintentionally do not take their AED medication on an occasional, regular, or frequent basis. A 5.9% of respondents self-reported that they intentionally do not take their medication as prescribed. A 6% of respondents self-reported that they are both unintentionally and intentionally nonadherent to their AED therapy. No significant associations were demonstrated between age, sex, perceived effectiveness of medication, feelings of stigma/embarrassment, adverse effects or additional neurological comorbidities, and unintentional or intentional nonadherence. A 28.5% of respondents to the questionnaire reported that they perceived themselves to have been subjected to medication error. Prescribing errors were the most common form of perceived medication error, followed by dispensing errors, then administration errors. Significant associations were found between ineffective medication and feelings of stigma or embarrassment about epilepsy with perceived prescribing errors. Intentional nonadherence to medication was significantly associated with perceived dispensing errors.
    背景与目标: :尽管有70%的癫痫患者(PWE)在采取适当的抗癫痫药(AED)方案后可实现癫痫发作自由,但证据表明PWE对AED的依从性不佳。对AED的不依从会增加发病率,死亡率,急诊就诊和住院治疗,依从性的降低也与生活质量降低,生产力下降和失业有关。此外,研究表明,在慢性病中普遍存在的用药错误在癫痫病中研究较少,但也有可能导致可避免的疾病发病率和死亡率。该项目的目标是通过自我报告的问卷确定药物依从率,并将其与在普通癫痫门诊就诊的PWE队列中感知到的药物错误相关。经过一个计划-研究-学习-行动周期,发现最合适的进行方法是定制的9项自我管理调查表。一百八十六个PWE完成了一个九个问题的问卷调查,询问患者自己的用药习惯以及他们以前曾遭受过用药错误的感觉。这项研究发现,有41%的受访者表示对AED治疗的依从性不佳,而28.5%的受访者自我报告说,他们无意间不定期,定期或频繁地服用AED药物。 5.9%的受访者自我报告说,他们有意不按处方服用药物。 6%的受访者自我报告说,他们无意和有意不遵守AED治疗。没有证据表明年龄,性别,药物治疗的有效性,耻辱感/尴尬感,不良反应或其他神经系统合并症以及无意或有意不依从之间存在显着相关性。问卷调查的28​​.5%的受访者表示,他们认为自己遭受了用药错误。开处方错误是感知到的用药错误的最常见形式,其次是配药错误,然后是给药错误。发现无效的药物与对癫痫病的耻辱感或尴尬感以及明显的处方错误之间存在显着关联。故意不坚持用药与感觉到的配药错误显着相关。
  • 【螳螂虾的路径整合错误和适应性搜索行为。】 复制标题 收藏 收藏
    DOI:10.1242/jeb.224618 复制DOI
    作者列表:Patel RN,Cronin TW
    BACKGROUND & AIMS: :Mantis shrimp of the species Neogonodactylus oerstedii occupy small burrows in shallow waters throughout the Caribbean. These animals use path integration, a vector-based navigation strategy, to return to their homes while foraging. Here, we report that path integration in N. oerstedii is prone to error accumulated during outward foraging paths and we describe the search behavior that N. oerstedii employs after it fails to locate its home following the route provided by its path integrator. This search behavior forms continuously expanding, non-oriented loops that are centered near the point of search initiation. The radius of this search is scaled to the animal's positional uncertainty during path integration, improving the effectiveness of the search. The search behaviors exhibited by N. oerstedii bear a striking resemblance to search behaviors in other animals, offering potential avenues for the comparative examination of search behaviors and how they are optimized in disparate taxa.
    背景与目标: :螳螂虾新角线虫Oerstedii种类在整个加勒比浅水域中占据着较小的洞穴。这些动物使用路径整合(一种基于矢量的导航策略)在觅食时返回家园。在这里,我们报告称,猪笼草的路径整合很容易在向外觅食的路径中积累错误,并且我们描述了猪笼草在未能按照其路径整合者提供的路线找到其家园后所采用的搜索行为。这种搜索行为形成了不断扩展的,无方向性的循环,这些循环的中心位于搜索起始点附近。在路径整合过程中,此搜索的半径将根据动物的位置不确定性进行缩放,从而提高了搜索的有效性。 Oerstedii猪笼草表现出的搜索行为与其他动物的搜索行为极为相似,为比较研究搜索行为以及如何在不同的分类群中进行优化提供了潜在的途径。

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