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1.
音乐治疗效应的动物实验研究   总被引:1,自引:0,他引:1  
李靖  王旭东 《四川动物》2007,26(1):196-197,200
近年来国内外关于音乐治疗效应的动物实验研究认为:音乐能影响动物的情绪;音乐还对动物的免疫功能、学习及记忆能力、以及动物的神经系统结构和功能等均有一定影响。该领域的研究有利于深入探索音乐疗法的作用机理。  相似文献   

2.
Reviewing the literature on time on task effects on safety shows contradictory evidence, especially with regard to 12 h shifts. It is argued that this might depend on methodological problems associated with the analysis of accident data, e.g. selectivity of samples, validity of data bases and study designs, especially for analyses at the company level. Analyses of aggregated data seem to indicate an exponential increase of accident risk with time on task beyond the normal working day. This is supported by some recent studies based on data from the Federal Republic of Germany.  相似文献   

3.
Hair evolution contributed to the biological success of mammals. Hair origin from synapsid scales is speculative and requires extensive modifications of the morphogenetic process transforming lens-shaped dermis of scales into small dermal papillae in hair. Hair evolution from glands is hypothetical but is supported from studies on the signaling control of hair vs. glandular morphogenesis. Based on immunocytochemical and comparative studies, it is hypothesized that the onion-like organization of hair derived from glandular pegs which central part produced lipids and some keratin. In a following stage, involucrin, trichohyalin, and keratins were produced in the central cells of the gland and formed a solid medulla surrounded by keratinocytes of the inner root sheath. The origin of this protohair was possibly related to increased concentration of beta-catenin and other signaling molecules in epithelial cells following the evolution of a dermal papilla. The latter activated the keratogenic genes, already utilized in cells of the claws, in concentric layers of cells of the glandular peg. Lipidogenic genes were depressed. As new genes evolved in the genome of synapsids, new circular layers of keratinocytes containing specialized hard keratins and keratin-associated proteins were formed around medullary cells. The new keratinocytes probably originated the cortex separating medulla from the external cells that became the inner root sheath. The hypothesis indicates that in a following stage, the medulla was obliterated or replaced by cortical cells while the external part of the cortex formed a cuticular surface due to the different growth rate with inner root sheath cells.  相似文献   

4.
Arabanase was purified by various procedures of gel filtrations and column chromatographies from the submerged culture filtrate of Aspergillus niger grown on the medium containing beet-araban as a carbon source, and the properties of the enzyme was examined. The purified enzyme was homogeneous protein in ultracentrifugal analysis, the optimum pH for enzymatic action was 4.0. The enzyme was thermostable at pH 6.0, namely, even after heating at 98°C for 10 minutes, 20.8 per cent of the initial activity still remained. The enzyme hydrolyzed beet-araban with producing l-arabinose.  相似文献   

5.
宋洁  刘学录 《生态学杂志》2019,30(3):1067-1078
应用生态学是自然资源管理和生态环境保护最重要的科学技术工具之一.在当前自然资源短缺、环境污染严重、生态系统退化的严峻形势下,对国际应用生态学的理论基础、研究方法、研究热点进行分析,对夯实我国应用生态学的知识基础、指明研究方向、确定战略定位具有重要意义.本文基于文献计量学原理,借助CiteSpace、Carrot2等信息可视化软件,以Web of Science中1980—2018年国际应用生态学研究领域基于不同检索策略的两个文献数据集合为研究对象,从研究载体、研究力量及研究内容3个维度进行文献时空分布、核心研究力量、研究热点演进以及研究前沿及趋势分析,旨在揭示其学科发展轨迹、研究现状与发展趋势,以期为未来我国的应用生态学研究提供参考.  相似文献   

6.
Summary The effects of different concentrations of KCl, K2SO4, MgCl2 and MgSO4 on the growth in length of the first seminal root of wheat, and on the change in fresh and oven-dry weight of the seedling and its component parts have been studied. The effect of mannitol was also investigated for comparison and to study the osmotic action. The effect of salts on root growth was dependent on salt species; all effects were specific to ions and not due to osmotic activity of solution. The growth of wheat roots was suppressed by concentrations of salts much lower than those required to suppress germination. All solutions of KCl from 0.1 to 50 me/l checked the growth of the root; the retardation increased with increase of concentration. In K2SO4 there was a slight activation of root growth for one day in 0.1 and 0.5 me/l; then the growth was suppressed after that. In all other concentrations from 1 to 50 me/l the growth was retarded. In MgCl2 or MgSO4 there was some activation of root elongation in 0.05, 0.1 and 0.5 me/l; but higher concentrations retarded root growth.  相似文献   

7.
The accumulation of biotin-vitamers in the culture media of a large number of microorganisms (about 700 strains) was studied. The contents of the biotin-vitamers were quantitatively determined by microbiological assays with Lactobacillus arabinosus and Saccharomyces cerevisiae.

It was found that large amounts of biotin-vitamers were accumulated by various microorganisms such as Streptomyces, molds and bacteria, and that the yield of biotin-vitamers was enhanced by the addition of pimelic acid or azelaic acid to the media. It was also found that the main portion of the vitamers accumulated by many microorganisms did not support the growth of Lactobacillus arabinosus, while it did support that of Saccharomyces cerevisiae. The small amounts of true biotin were observed in the culture media of various Streptomyces and molds, but hardly in the culture media of bacteria.

The identification of biotin-vitamers accumulated by various microorganisms is described, and the distribution of the vitamers in microorganisms is also described.

The results presented in this paper show that the main component of the vitamers accumulated by many microorganisms is identified as desthiobiotin by anion exchange column chromatography, paper chromatography and chemical analysis. Small amounts of fraction B (unidentified vitamers) and Fraction D (biotin) were also detected in the culture media of various molds and Streptomyces. However, these fractions were not observed in the culture media of any bacteria tested.

It was also found that large amounts of an unknown biotin-vitamer was accumulated by various bacteria. The vitamer was avidin-uncombinable, and, from the paper electrophoretic studies, it was assumed that the vitamer might be an analogue of pelargonic acid.  相似文献   

8.
马铃薯Y病毒属(Potyvirus)研究的文献计量分析   总被引:3,自引:0,他引:3  
[目的]马铃薯Y病毒属(Potyvirus)是世界上最大的两个植物病毒属之一,对多种农作物造成危害.利用文献数据库,客观地分析国内外Potyvirus研究的发展动态,为国内外Potyvirus科研工作者和决策者提供参考.[方法]基于Web of Science数据库,采用文献计量学方法,对全球发表于1985-2012年的Potyvirus文献的国家、作者、机构、载文期刊及研究内容进行了数量和质量分析.[结果]检索到全球60个国家发表的Potyvirus文献2 442篇,以及每篇文献的被引频次和每个国家、机构及作者的H指数.经分析得出:全球Potyvirus研究论文的产出量自1991年呈稳定上升趋势,文献的数量和质量在统计的国家中,以美国最好,其次是法国、西班牙、澳大利亚、英国;美国的高产活跃作者最多;Potyvirus研究的热点是基因沉默和分子生物学,并随着研究技术方法的革新将不断深入;研究方向更多倾向于寄主方面的研究(如基因沉默、寄主抗性、与寄主互作等)及交叉学科;而中国在Potyvirus基础研究上距离国际先进水平还有很大距离,研究力量较少,有影响力的论文较少.[结论]美国在该领域的研究处于领先水平,我国仍需加强Potyvirus基础研究力量投入,努力缩短差距.  相似文献   

9.
以自制的壳聚糖作为载体,用戊二醛作交联剂,优化了固定化条件,研制成壳聚糖固定化木瓜蛋白酶。其活性回收率达到42—53%,操作半衰期达到一个月以上,对热、乙醇以及尿素的稳定性有很大的提高,Km值为0.67×10~2mg/mL,最适温度65—70℃,最适pH8.0,能使啤酒中的蛋白质浓度从56.5mg/L减少到2.7mg/L,可以消除啤酒的低温混浊现象。  相似文献   

10.
11.
基于“参照系-现状-变化量”的生态系统评估方法   总被引:1,自引:1,他引:0  
生态系统评估是开展生态系统管理的重要手段,其评估结果已成为衡量区域生态系统状况优劣的重要依据。由于没有充分考虑生态系统禀赋的区域差异性,缺乏有效区分气候变化和人类活动影响的手段,导致生态系统评估结果的实用性与区域可比性一直存有争议。在生态大数据背景下,基于生态完整性理论,结合长期地面监测数据、野外调查数据、遥感数据等海量数据,耦合生态系统过程模型,构建了基于“参照系-现状-变化量”(RSD)的生态系统评估体系,以受干扰较少接近原生、完整的地带性植被生态系统(完整的生态系统)作为参照系,其表现出来的组成、结构、功能等特征为参照条件,生态系统状况现状与参照条件的偏离程度作为评估生态系统优劣程度的依据,从而将现状评估转变为变化量评估,增强评估结果的时空可比性。并以生态系统过程模型为工具,利用RSD评估方法评估了中国陆地生态系统生产力功能,验证了该方法体系的可行性。评估结果显示,2000—2018年我国植被净初级生产力(NPP)参照值、现实值和变化量均表现为上升趋势,而NPP现实值与变化量的空间分布存在显著差异,基于RSD的评估方法较好地解决了评估结果区域不可比的问题。研究对完善我国生态系统评...  相似文献   

12.
Study on gene sensor based on primer extension   总被引:1,自引:0,他引:1  
Based on the fact that the resonant frequency of a piezoelectric crystal is the function of its surface deposit, and that the primer extends after it hybridizes with the template, the primer extension gene sensor technique was developed. The prominent feature of the technique is that fast and sensitive frequency signals are used as the monitoring system of gene hybridization and primer strand extension. Results show that this technique may be used in homologous analysis of nucleic acid, trace DNA detection, and determining the integration of DNA. It may also be used for isolation of target gene, gene mutation analysis, and predicting the location of a gene in its genome.  相似文献   

13.
祁栋灵  孙瑞  杨川  兰国玉  谢贵水  吴志祥 《生态学报》2016,36(22):7505-7508
为持续加强热带森林生态学科技工作者之间的相互了解、促进学术交流与合作。2016年8月12—14日在海口举行了以"做实生态学基础,服务美丽热区建设"为主题的第七届热带森林生态学学术研讨会,有18位生态学领域的研究者做了学术报告,报告内容涵盖了热带森林生态服务功能评估、热带森林生态系统物质与能量的循环、环境对热带森林物质能量循环的影响、海南岛植物区系与海南岛的起源、热带植物种类资源调查分析、热带生态资源资产核算、热带人工林生态及科学发展、以及热带森林生态学野外观测技术等。  相似文献   

14.
孙名浩  李颖硕  赵富伟 《广西植物》2023,43(8):1375-1382
遗传资源数字序列信息(DSI)是测序技术的产物,至少包括DNA、RNA等遗传物质的序列信息和天然产物化学结构信息等,其获取和利用以及由此产生的利益分配问题已经成为《生物多样性公约》等国际进程的热点和焦点。自2016年以来,《生物多样性公约》框架下各方对此虽然开展了卓有成效的讨论,但在DSI内涵和外延、与遗传资源的关系、开放获取、监测DSI的利用等领域仍然存在根本分歧。DSI获取与惠益分享问题面临政治博弈、技术障碍、国内法与国际法协调、多公约协同等多重挑战。我国作为全球DSI的主要提供国和利用国,为有效应对DSI获取与惠益分享所带来的挑战和机遇,有必要加强以下方面的相关工作:(1)加强DSI的相关基础研究工作,特别是需要强化跨学科研究,并开展惠益分享试点示范;(2)适时制定生物信息数据管理制度,系统构建生物资源数据分类、汇交、共享、研究、利用、跨境传输、惠益分享等关键制度;(3)加快建成开放、安全、共享、互惠的全球性生物资源数据生产和存储基础设施,加强生物资源数据国际合作;(4)充分发挥诸如中国生物多样性保护国家委员会等跨部门协调机制作用,持续加强我国参与DSI相关国际论坛讨论的协同增效。  相似文献   

15.
本文阐述了心理对生理的能动作用。在一定的条件下,人的心理可影响其生理功能,两者互为因果、相互影响。生理是心理活动的物质基础,心理是其生理的驱动力和标志。本文论述了精神、情绪、意念、信念、暗示等心理活动对生理的影响和作用及中医论心理对生理的作用,中医利用情志疗法的理论达到心理对生理趋向健康的作用。同时论证了肠道菌群通过心理间接影响生理功能,通过微生态制剂调节肠道菌群的微生态平衡,可改善患者的神经症状,使之心理活动达到最佳状态,进而使人的生理趋向健康。  相似文献   

16.
目的 通过多层感知器网络的构建评价过度医疗防治的效果,为进一步完善过度医疗防治体系提供参考。方法 基于多层感知器网络,构建了具有三层神经网络、9个隐含层节点数的过度医疗绩效评价模型。结果 多层感知器网络的训练结果与专家评价(期望结果)两者评价是完全一致的。 结论 该多层神经网络及其评价指标的选取能够很好的应用于医疗服务中的过度医疗防治绩效评价。  相似文献   

17.
Semiallogeneic and allogeneic immunization protocols were used to clarify the origin of two antibody activities: (a) those directed at alloantigens and (b) those directed at receptors for alloantigens. In a first variant of semiallogeneic immunization, parental strain spleen cells were injected into F1 hybrid hosts where they could not be rejected; both antireceptor antibody and alloantibody activities appeared, persisting for over 10 weeks. When the host was irradiated, no antireceptor antibody was formed, indicating the F1 origin of this activity. In the second variant of semiallogeneic immunization, F1 spleen cells were injected into parental hosts. Here the antireceptor antibody, while reaching high titers, even in hosts presensitized to antigens of the donor, soon disappeared, presumably due to the rejection of inoculated cells. It was concluded that in both variants of semiallogeneic situations, antireceptor antibodies were formed by F1 cells, whereas alloantibodies were formed by parental cells. In allogeneic immunizations, four activities were found in serum —two directed at alloantigens (one set from each partner) and two directed at receptors for alloantigens (one set from each partner) —indicating that lymphoid cells of any origin can function as producers of antibodies to alloreceptors, in strict analogy to their potential as producers of antibody to alloantigens.  相似文献   

18.
荧光适配体作为一种无需标记的荧光探针,具有许多潜在的优势,并被应用于多种靶物质(如ATP、RNA)的检测,是目前适配体研究领域的热点。孔雀石绿适配体(malachite green aptamer,MGA)属于荧光适配体,其能通过配体诱导折叠形成结合口袋,进而促进孔雀石绿(malachite green,MG)的发光。目前,已经筛选得到的MGA的种类较少,主要介绍了已知的MG RNA适配体及其变构体和MG DNA适配体的特性,以及影响MG-MGA复合物荧光强度的因素。同时,还对主要的MG衍生物和共聚物进行了总结。最后,综述了MGA在生物传感、荧光成像等方面的应用,并对MGA的发展方向进行了展望,以期为MGA在生物检测、生物成像等方面的应用提供指导。  相似文献   

19.
Highly charged water-soluble conjugates of amyloglucosidase with a copolymer of ethylene-maleic acid or styrene-maleic acid were prepared and adsorbed on DEAE-cellulose and other cationic resins. Negatively charged enzyme conjugates were also obtained by means of succinylation. The polyanionic conjugates of amyloglucosidase adsorbed on the cationic carriers show higher temperature stability than the native enzyme adsorbed on the same carriers under the same experimental conditions. The insoluble enzyme conjugate-carrier complexes could be reused and retained their full activity while working continuously for three weeks. The application of the insoluble enzyme preparations with the above characteristics which could possibly satisfy the requirements for industry are discussed.  相似文献   

20.
微量元素锌和超氧化物歧化酶对产蛋鸡影响的研究   总被引:1,自引:0,他引:1  
结果表明:与对照相比,加锌Ⅱ组鸡的产蛋率高(P<0.05),破壳率低(P<0.01);加锌Ⅱ组鸡的产蛋率高(P<0.01),破壳率降低(P<0.01),蛋重增加(P<0.05)饲料消耗减少,Ⅱ组与Ⅲ组比较,生产性无显著差异。Ⅱ组和Ⅲ组肝中GOT和GPT、血清中AKP酶活性显著增加(P<0.01)肝中AKPⅡ组明显上升(P<0.05),Ⅲ组显著提高(P<0.01),SOD酶活性Ⅱ明显增加(P<0.05),Ⅲ组显著上升(P<0.01),Ⅱ组与Ⅲ组比较,肝中GOT和AKP存在显著差异(P<0.01)。其它酶活性各组间无明显差异(P<0.05)。鸡蛋中的锌含量Ⅱ和 Ⅲ组大幅度上升(P<0.01),Ⅲ组磷脂降低(P<0.05),Ⅱ组不受影响(P<0.05)。铁和各种氨基酸含量无明显变化(P<0.05)。肝脏、肺脏、肌肉和翅羽中的锌含量Ⅱ组和Ⅲ组显著增加(P<0.01)能脏中的锌含量Ⅱ组明显上升(P<0.05),Ⅲ组显著提高(P<0.01),心脏、脾脏和卵巢无显著影响(P<0.05)。  相似文献   

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