Comparison Study of Bone Defect Healing Effect of Raw and Processed Pyritum in Rats

To evaluate and compare the effect of raw and processed pyritum on tibial defect healing, 32 male Sprague Dawley rats were randomly divided into four groups. After tibial defect, animals were produced and grouped: sham and control group were orally administrated with distilled water (1 mL/100 g), while treatment groups were given aqueous extracts of raw and processed pyritum (1.5 g/kg) for successive 42 days. Radiographic examination showed that bone defect healing effect of the treatment groups was obviously superior compared to that of the control group. Bone mineral density of whole tibia was increased significantly after treating with pyritum. Inductively coupled plasma-optical emission spectrometry showed that the contents of Ca, P, and Mg in callus significantly increased in the treatment groups comparing with the control. Moreover, serological analysis showed that the concentration of serum phosphorus of the treatment groups significantly increased compared with that of the control group. By in vitro study, we have evaluated the effects of drug-containing serum of raw and processed pyritum on osteoblasts. It was manifested that both the drug-containing sera of raw and processed pyritum significantly increased the mRNA levels of alkaline phosphatase and collagen type I. Protein levels of phosphorylated Smad2/3 also increased. The mRNA levels of osteocalcin and transforming growth factor β (TGF-β) type I and II receptors, as well as the protein levels of TGF-β1 in the processed groups, were higher than those in the control. In summary, both raw and processed pyritum-containing sera exhibited positive effects on osteoblasts, which maybe via the TGF-β1/Smad signaling pathway. Notably, the tibia defect healing effect of pyritum was significantly enhanced after processing.     

多功能农业景观:内涵、进展与研究范式

多功能农业景观是景观尺度下农业多功能性的空间表征，具有生物多样性保护、田园风光留存和地域文化传承等多种重要的非经济功能。构建多功能农业景观是促进区域农业可持续发展与人类福祉提升的重要途径，同时也是多学科交叉的综合性研究。在已有景观生态学研究范式的基础上，探讨了多功能农业景观的内涵和国内外相关研究进展，并提出了"格局-功能-需求-管理"的多功能农业景观研究范式。与此同时，绘制了新研究范式的概念框架，通过划分四大研究模块具体分析了如何基于新研究范式开展多功能农业景观的构建、评价和管理等工作。本研究为实现区域农业景观的可持续发展和阐明多功能农业景观的内在运行机制奠定理论基础提供支持，为乡村生态景观营造关键问题的解决与多功能农业景观的实际构建提供帮助。     

嗅觉受体在非嗅觉组织和细胞中的作用及其机制

嗅觉受体(olfactory receptor)不仅表达在鼻腔中,还广泛表达在全身其他部位,起着重要的生理作用.本文综述了非嗅觉组织和细胞中表达的嗅觉受体及其功能,这些嗅觉受体通过调控细胞周围的内源性化学物质,维持正常的生理功能,并且能在选定的外源性配体刺激下,表现出特定的功能.在医药领域,大约有40%上市药物的作用靶点都来自于G蛋白偶联受体(GPCR)家族,而嗅觉受体是GPCR中最大的基因家族,鉴于其表现出的重要作用,我们推测这些嗅觉受体可能成为未来重要的药物靶标.本文对非嗅觉组织和细胞中嗅觉受体功能的综述,一方面有利于将其作为潜在药物靶点,开发新的药物,另一方面也为中药中挥发性单体的药理作用提供了新的研究思路.     

Flow injection–chemiluminescence determination of acyclovir

The chemiluminescence (CL) reaction of acyclovir (ACV)–potassium permanganate, with formaldehyde as an enhancer, was investigated by the flow‐injection system, and a new method is reported for the determination of ACV on the basis of the reaction. The method is rapid, effective and simple for the determination of acyclovir in the range 0.2–80 mg/L, with a limit of detection of 0.06 mg/L (3 S:N), a relative standard deviation (RSD) of 3.7% for the determination of 1.0 mg/L acyclovir solution in 11 repeated measurements. The method has been applied to the determination of acyclovir in pharmaceuticals, with satisfactory results. The possible reaction mechanism is also discussed briefly. Copyright © 2011 John Wiley & Sons, Ltd.     

基于享乐价格-结构方程双模型的西宁城市湿地生态系统服务价值及影响因素研究

湿地为城市发展提供巨大的生态系统服务，但其被市场“认可”的经济价值难以准确评估。以青海省西宁市城市湿地为例，筛选房屋结构、可达性、环境、湿地等10个因子，采用享乐价格模型对110个湿地周边社区样点的因子数据(2020年)进行分析，定量分析城市湿地被市场“认可”的价值量。采用断裂点理论和加权Voronoi图模型方法等，分析了湿地生态系统服务价值的空间影响范围；构建了湿地生态系统服务价值影响因素的结构方程模型，探究了影响湿地生态系统服务价值的主要因素。结果表明：(1)2020年湟水城市湿地的总价值达到3.367亿元，约有54.3%的生态系统服务通过房产被市场转化；(2)湟水湿地单位面积的生态系统服务价值为151.916元/m~2,生态系统服务价值由大到小排列：火烧沟(1.632亿元)>海湖湿地(0.710亿元)>宁海湿地(0.629亿元)>北川湿地(0.330亿元);(3)湿地生态系统服务价值占房产总价值的比例达到2.04%,位列10个因素中的第7位；线性函数模型结果显示，购买者对湿地的边际支付意愿是0.12元/m~2,即购买者愿意为房产与湿地之间的距离每缩小1m而多支付...     

基于环境库兹涅茨曲线的我国大气污染防治重点区域环境空气质量与经济增长关系研究

改革开放以来，中国经济迅猛发展，但大气污染等环境问题日益突出。进入21世纪，我国通过颁布实施多项大气污染防治政策，将京津冀及周边地区、长三角地区、珠三角地区等大气污染较严重的区域划定为重点区域，针对性制定治污措施和实施减排工程，努力推动区域环境空气质量改善。基于2000-2019年我国31个省（自治区、直辖市）（以下简称31个省份）GDP，以及SO₂、PM₁₀、NO₂三项大气污染物浓度数据，利用环境库兹涅茨曲线（EKC，Environmental Kuznets Curve）模型，对31个省份和京津冀及周边地区、长三角地区、珠三角地区的经济增长情况、大气污染物浓度演变以及二者之间的关系进行了系统全面的分析评估。研究结果显示：（1）近年来实施的各项大气污染防治政策，特别是2013年以来颁布实施的《大气污染防治行动计划》《打赢蓝天保卫战三年行动计划》，推动环境空气质量改善的同时，促进了经济发展与环境保护长期关系协调性逐步增强，除NO₂浓度呈U型外，31个省份SO₂浓度、PM₁₀浓度与人均GDP的EKC曲线呈倒U型和倒N型，并处于快速下降阶段。（2）京津冀及周边地区SO₂浓度与人均GDP呈倒U型，且处于快速下降阶段；PM₁₀和NO₂浓度均呈现U型关系，且均处于上升期。（3）长三角地区SO₂、PM₁₀浓度与人均GDP呈现倒U型和U型，但均处于下降阶段；NO₂浓度与人均GDP无相关关系。（4）珠三角地区SO₂、PM₁₀和NO₂浓度与人均GDP均呈现倒U型关系，且均处于下降阶段。为此，建议"十四五"期间我国政府要继续实施新一轮的大气污染防治行动计划，聚焦机动车NO_x污染管控，大力推动NO₂浓度稳步下降，以实现我国环境空气质量持续改善，为统筹经济高质量发展和生态环境高水平保护奠定坚实基础。     

Response of grazing snails to phosphorus enrichment of modern stromatolitic microbial communities

1. The effects of added phosphorus (P) on the growth, P and RNA : DNA contents, and survivorship of snails grazing on laminated microbial mats (living ‘stromatolites’) were examined in the Rio Mesquites at Cuatro Ciénegas, Mexico (total P, c. 0.60 μmol L^?1) to test the hypothesis that strong P‐limitation of microautotroph growth produces a stoichiometric constraint on herbivores because of mineral P‐limitation. 2. In a 3‐week experiment performed in summer 2001, addition of phosphorus (+15 μmol L^?1) resulted in a strong decline in stromatolite biomass C : P ratio from very high levels (c. 2300 : 1 by atoms) to moderate levels (c. 550 : 1). The endemic hydrobiid snail Mexithauma quadripaludium responded to P‐enrichment with elevated body P content and higher RNA : DNA ratios, especially for small animals likely to be actively growing. This positive response is consistent with the existence of a stoichiometric constraint on snail growth. 3. In a longer experiment (8 weeks) involving a more moderate P enrichment (+5 μmol L^?1) in summer 2002, P enrichment reduced stromatolite C : P ratio from moderate values in control treatments (c. 750) to very low values (<100 : 1). Snails responded to stromatolite P‐enrichment with increased body P content but, in contrast to the first experiment, with lower RNA : DNA ratio, lower growth rates, and higher mortality. 4. These contrasting results suggest that both very high and very low biomass C : P ratios in stromatolites are detrimental to M. quadripaludium performance, leading us to hypothesise that these herbivores live on a ‘stoichiometric knife edge’.     

昆虫击倒抗性基因突变对钠通道功能的影响

该文综述了昆虫钠通道基因的表达与功能特性、击倒抗性突变的功能和这些突变对钠通道门控的影响,以及钠通道基因突变与抗性表现型之间的因果关系;还讨论了这些突变增强击倒抗性的分子机理。