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11.
Acute kidney injury (AKI) is a high frequent and common complication following acute myocardial infarction (AMI). This study examined and identified the effect of AMI-induced AKI on organic anion transporter 1 (Oat1) and Oat3 transport using clinical setting of pre-renal AKI in vivo. Cardiac ischaemia (CI) and cardiac ischaemia and reperfusion (CIR) were induced in rats by 30-min left anterior descending coronary artery occlusion and 30-min occlusion followed by 120-min reperfusion, respectively. Renal hemodynamic parameters, mitochondrial function and Oat1/Oat3 expression and function were determined along with biochemical markers. Results showed that CI markedly reduced renal blood flow and pressure by approximately 40%, while these parameters were recovered during reperfusion. CI and CIR progressively attenuated renal function and induced oxidative stress by increasing plasma BUN, creatinine and malondialdehyde levels. Correspondingly, SOD, GPx, CAT mRNAs were decreased, while TNFα, IL1β, COX2, iNOS, NOX2, NOX4, and xanthine oxidase were increased. Mitochondrial dysfunction as indicated by increasing ROS, membrane depolarisation, swelling and caspase3 activation were shown. Early significant detection of AKI; KIM1, IL18, was found. All of which deteriorated para-aminohippurate transport by down-regulating Oat1 during sudden ischaemia. This consequent blunted the trafficking rate of Oat1/Oat3 transport via down-regulating PKCζ/Akt and up-regulating PKCα/NFκB during CI and CIR. Thus, this promising study indicates that CI and CIR abruptly impaired renal Oat1 and regulatory proteins of Oat1/Oat3, which supports dysregulation of remote sensing and signalling and inter-organ/organismal communication. Oat1, therefore, could potentially worsen AKI and might be a potential therapeutic target for early reversal of such injury.  相似文献   
12.
本原直脉蝎蛉化石标本采自陕西铜种中三叠世铜川组下段上部(T21^2)灰绿色泥页岩,中描述2个新种,并附上产于世界各地的10个种主要特征的检索表,新种的模式标本保存在北京自然博物馆。  相似文献   
13.
西藏林芝地区药用蕨类植物资源   总被引:1,自引:0,他引:1  
本文对西藏林芝地区药用蕨类植物 39种 ,从产地、生境、海拔范围、性味、功效等作了初步分析  相似文献   
14.
基于FMT-AHP的海南农垦花岗岩类多雨区橡胶园地力评价   总被引:1,自引:0,他引:1  
海南农垦是中国最大的天然橡胶生产基地,自第二次全国土壤普查以来橡胶园养分状况已发生了很大变化,但具体情况如何尚不清楚。运用耕地地力评价方法对海南农垦主要橡胶园的地力进行了系统评价,以期为橡胶园地力提升和天然橡胶的可持续发展提供理论支持。以土壤母质类型和降雨量为依据,首次将海南农垦橡胶园划分为8个类型区,并选取占海南农垦橡胶园总面积56.97%的花岗岩类多雨区作为评价区域,采集7204个0—20 cm层的土壤样品,运用特尔菲法、模糊数学理论和层次分析法确定11个评价指标及其权重,将评价区橡胶园地力划分为5等。研究结果发现:评价区以中间地力水平的二等、三等、四等橡胶园为主,占评价区橡胶园总面积的85.85%,它们广泛分布于琼中、屯昌、澄迈、儋州、万宁、保亭、乐东、三亚、陵水、定安、琼海、五指山、昌江、文昌和东方15个县市;一等地面积很小且分散,五等地相对集中面积也很小。相关分析表明土壤pH、有机质、有效磷和速效钾含量是影响评价区橡胶园地力水平的重要因素。评价区橡胶园土壤pH适宜橡胶树正常生长,但该区域土壤有机质和有效磷含量不能满足橡胶树正常生长的需要,而该区域一、二等地土壤速效钾含量能满足橡胶树正常生长,其三、四等地土壤速效钾含量仅达到橡胶树正常生长所需水平,随着地力下降到五等其土壤速效钾含量已不适宜橡胶树正常生长。根据上述研究结果,笔者建议橡胶园应大力间作绿肥,在增施有机质的基础上补氮、补钾、施用钙镁磷肥,同时加强养分管理,提高肥料利用率。  相似文献   
15.
陈筝 《生物信息学》2018,25(1):106-111
高密高异质性城市环境不仅影响空间审美感受,也影响着城市居民的心理健康。实证研究表明通过引入绿色自然、优化空间设计可缓解这种负面影响。本文结合已有的神经认知学和医学研究,将风景园林学科核心价值之一环境愉悦体验提升到公共健康高度。我们利用神经生物测量等一系列先进技术量化环境体验,并在医学和神经认知学已有实证证据的基础上进一步进行健康影响评价,提出基于健康影响评价的循证设计方法。具体包括测量高密高异质性街道中不同环境空间要素组合对人的健康影响,分析识别具体案例中最容易诱发压力和认知负荷的空间要素,针对性地提出设计干预策略并依托增强现实/虚拟现实技术进行绩效预估。研究整合了技术量化环境体验和环境神经健康评价这2个密切联系的学术前沿,其成果可以直接指导具体案例的循证设计优化。  相似文献   
16.
Drinking water contaminated with arsenic poses serious threat to the human health. The present study was aimed for quality assessment of the groundwater of Khairpur Mir's in respect with arsenic and other elemental contamination like Fe, Cu, Co, and Ni. The presence of the trace elements in groundwater from different sources in the study area was measured by using atomic absorption spectroscopy. For arsenic analysis hydride generation technique (MHS-15) was used with detection limit of 0.02 µg l?1. Elevated level of arsenic was observed in most of the samples as compared to recommended value of World Health Organization (WHO) guidelines (10 µg l?1). However, levels of Fe, Cu, Co, and Ni in hand pump (HP) water samples was found in the range of 4–1610 µg l?1, 0–556 µg l?1, 0–230 µg l?1, and 0–700 µg l?1, respectively. Whereas in tube well (TW) water samples the observed values are 5–1620 µg l?1, 0–50 µg l?1, 4–110 µg l?1, and 0–360 µg l?1 for Fe, Cu, Co, and Ni, respectively. Significant difference was observed between TW and HP water samples. It was concluded that the level of arsenic found was very high up to 13 fold more than the WHO recommended limit in study area. While the levels of other elements was noted within the safe limit.  相似文献   
17.
1. We tested the degree to which a lake's landscape position constrains the expression of limnological features and imposes a characteristic spatial pattern in a glacial lake district, the Northern Highland Lake District in north‐central Wisconsin. 2. We defined lake order as a metric to analyze the effect of landscape position on limnological features. Lake order, analogous to stream order, is based solely on geographical information and is simple to measure. 3. We examined the strength of the relationship between lake order and a set of 25 variables, which included measures of lake morphometry, water optical properties, major ions, nutrients, biology, and human settlement patterns. 4. Lake order explained a significant fraction of the variance of 21 of the 25 variables tested with ANOVA. The fraction of variance explained varied from 12% (maximum depth) to 56% (calcium concentration). The variables most strongly related to lake order were: measures of lake size and shape, concentrations of major ions (except sulfate) and silica, biological variables (chlorophyll concentration, crayfish abundance, and fish species richness), and human‐use variables (density of cottages and resorts). Lake depth, water optical properties, and nutrient concentrations (other than silica) were poorly associated with lake order. 5. Potential explanations for a relationship with lake order differed among variables. In some cases, we could hypothesize a direct link. For example, major ion concentration is a function of groundwater input, which is directly related to lake order. We see these as a direct influence of the geomorphic template left by the retreat of the glacier that led to the formation of this lake district. 6. In other cases, a set of indirect links was hypothesized. For example, the effect of lake order on lake size, water chemistry, and lake connectivity may ultimately explain the relation between lake order and fish species richness. We interpret these relationships as the result of constraints imposed by the geomorphic template on lake development over the last 12 000 years. 7. By identifying relationships between lake characteristics and a measure of landscape position, and by identifying geomorphologic constraints on lake features and lake evolution, our analysis explains an important aspect of the spatial organization of a lake district.  相似文献   
18.
19.
肖强  胡聃  肖洋  李勇志  谭宏  黄勇 《生态学报》2012,32(11):3577-3585
许多研究文献忽略了经济增长和生态环境质量的双向作用机制,从而导致了变量之间的内生性偏差。与以往研究相比,主要在以下几方面进行分析:1)采用脉冲响应函数来分别考察生态环境与经济增长这两类变量之间的动态冲击反应。2)运用预测方差分解技术来考察经济增长与生态环境变化在解释因素变动时的相对重要性。结论:经济增长与生态环境之间存在长期的均衡关系,非平稳序列的经济增长指标、生态环境因子经过一阶差分后变得平稳,均为一阶单整,存在协整统计关系。从长期来看,人均GDP与废气排放量、固废排放量呈现负相关,而与矿产开采总量、化肥使用强度呈现正相关。其高度正相关性实证了该地区主要靠资源开发拉动经济增长。脉冲响应分析表明,快速经济增长是影响生态环境质量的重要原因,生态环境质量变化对经济增长存在着反作用力。就响应效果而言,生态环境对经济增长的负向响应表明生态环境退化将导致人们对生态环境质量需求偏好的改变,从而对经济增长进程的变化产生外在压力,但生态环境对经济增长的反馈效应具有滞后性。  相似文献   
20.
北京市房山区植被丰富,以暖温带落叶阔叶林为主,并混生温带针叶林,表现出明显的垂直地带性分布。通过对北京市房山区进行野生植物资源调查,统计出共有野生植物80科,259属,409种,同时分析了房山区野生植物资源在园林中的潜在应用价值;另外,通过对比相关濒危植物资料,总结出房山区的濒危植物21种,并就重点保护植物保护策略进行探讨。  相似文献   
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