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1.
本文研制了用生物倒置显微镜和以微通道板为核心的超高灵敏度光电成像系统组成的光子计数显微成像系统,此系统具有高空间放大倍数(160×)和极高的光子放大倍数(107),可探测到大小为μm量级,发光强度为100光子/秒的发光图像。应用此系统拍摄到了单个明亮发光杆菌(Photobacteriumphosphoreum)的发光图像,图像显示明亮发光杆菌的大小为2.4×0.60(μm)2,单个细菌的发光强度在100光子/秒量级。上述实验为明亮杆菌在环境保护中的应用提供了基本参数,也为进一步从细胞水平上研究发光细菌提供了可能。  相似文献   

2.
人体超微弱发光图像中的信号检验   总被引:1,自引:0,他引:1  
用近期研制的具有单光子探测能力的超高灵敏度成像系统获得了人体体表生物超微弱发光的强度数据。为分析图像中的信号检验,二项分布被用于人手不同时间累积发光图像中的信号显著性检验,证实人手存在超微弱生物发光,手指的发光强度在300~550photons/s范围内,全手的发光强度在850~1200photons/s范围内。  相似文献   

3.
自发和光诱导的生物超微弱发光图像的观测   总被引:3,自引:0,他引:3  
邢达  谭石慈 《激光生物学报》1997,6(2):1035-1039
本文报导一种最新研制的高探测灵敏度,低噪声的光子图像观测系统。利用该系统观测了绿豆芽,小葱和树叶等活体品的超弱发光图像。  相似文献   

4.
生物样品超弱发光图象的探测与分析   总被引:14,自引:1,他引:13  
介绍了生物超弱发光图象探测系统及其原理。利用该系统对与黄化绿豆芽叶绿体形成相应的光诱导超弱发光(UWL)图象进行了实时观察。认为,叶绿体在生物超弱发光中起重要作用,但植物的超弱发光不是叶绿素本身直接受光照射后的瞬发荧光。另外,对几种不同生物样品的超弱发光图象进行了探测。实验表明,对应生物的不同生长代谢阶段及不同部位有不同的超弱发光强度。利用这种探测和分析,可以得到一种无损探测生物的生理、生化状态及变化过程的直观、灵敏的实用方法。  相似文献   

5.
本文介绍了自行研制的二套系统及其应用。1.高灵敏荧光显微镜系统,该系统探测灵敏度达到10-6lx量级,比普通CCD系统提高了104倍,系统用宽量程照度计对微弱光成象性能进行了标定,在给出细胞荧光图象的同时,可以给出每一象元的发光强度,并可给出视觉更易分辨的光强的三维显示和伪彩色图象。在该系统上得到了分红菌甲素在Hela细胞中的分布图象,Hela细胞加入竹红菌甲素后的光照损伤及抗氧化剂维生素E等对细胞的保护图象。2.光子计数成象系统,该系统灵敏度达10-8lx量级,可探测到单个光子及其分布,在其上得到了绿豆芽,树叶,昆明鼠,人手及手指的超微弱发光的光子图象,并用统计理论进行了信号检验。  相似文献   

6.
微弱发光分析技术应用实例(四)   总被引:7,自引:0,他引:7  
植物生理变化往往伴随着发光过程,探测这种发光过程,寻求其规律性,对于农业、林业科学研究具有重要意义.BPCL型微弱发光测量仪的样品室可以直接测量各种生物(植物、动物)体系的发光.超弱发光测量对于大豆种子生理变化敏感,有可能作为品种鉴定的手段之一.微弱发光动力学测量是具有应用前景的新方法,可用于多种植物的抗逆性研究.  相似文献   

7.
生物中的超微弱发光   总被引:17,自引:0,他引:17  
超微弱发光是所有生物都具有的一种普遍现象,发光强度极其微弱,量子效率也很低,波长范围广,自1923年发现超微弱发光以来,各国科学家做了大量的研究,对机理进行探讨,目眼微弱发光的柚是依然不很清楚。生物超微弱发光在许多领域得到广泛的应用,由超微弱发光研究发展为的发光检测技术快速,简便,而且不会对组织材料造成损伤。本语文就生物超微弱发光机理及应用研究进行了综述。  相似文献   

8.
随着生物超微弱发光检测技术的发展,越来越多的学者将该技术应用于医疗领域方面的研究。本文通过分析、总结,发现生物超微弱发光在现代医学中不仅能够协助疾病诊断、评估人体皮肤状态,还能应用于针灸、中药药性、中医证型的医疗当中。此外,本文还引入了除光子强度外的其他参数[Q值、压缩状态参数(SSI)和Fano因子],并对情绪、运动、死亡过程的生物超微弱发光变化也进行了总结。生物超微弱发光在医疗领域应用广泛,实用性强。本文对其进行综述,以期对人体超微弱发光有更详细的了解,展示生物超微弱发光在医疗领域的发展潜力。  相似文献   

9.
白菜叶绿体的超弱发光机理初探   总被引:1,自引:0,他引:1  
从先前对黄化绿豆幼苗光形态建成过程和花生叶片不同发育阶段的超弱发光 (UBE)图象的初步观察结果来看 ,植物的 (诱导 )超弱发光与光形态建成和光合作用等生长代谢过程密切相关 (李德红等 ,1998)。我们在此工作的基础上 ,利用自行研制的超弱发光图象探测系统对叶绿体的超弱 (延迟 )发光进行了研究 ,并初步探讨了温度和某些化学试剂对叶绿体超弱发光的影响。实验材料选用白菜 (BrassicapekinensisRupr .)叶片 ,按通常的方法分离纯化叶绿体 ,经相应处理后分别装于比色皿中 ,按前文的方法观测其超弱发光。叶绿体无论…  相似文献   

10.
微弱发光分析技术原理及应用实例(一)   总被引:10,自引:0,他引:10  
微弱发光分析技术近年得到迅速发展,在自由基、活性氧分析、化学发光分析、生物的超微弱发光分析、发光免疫分析、生物发光分析等领域得到广泛应用.简要介绍了微弱发光分析技术的测量原理,并以一些研究成果为实例讲解如何应用微弱发光分析技术进行研究和实践.  相似文献   

11.
UV-B处理外起绿豆幼苗下胚轴原生质体的收缩;绿豆幼苗的下胚轴的伸长亦受UV-B处理的显著抑制。统计分析证实两者呈显著正相关(r^2=0.8066)。这一结果表明,UV-B对绿豆下胚轴生长的抑制作用与不胚轴细胞伸长受到抑制相关。  相似文献   

12.
Alpha-amylase from germinated mung beans (Vigna radiata) has been purified 600-fold to electrophoretic homogeneity and a final specific activity of 437 U/mg. SDS-PAGE of the final preparation revealed a single protein band of 46 kDa. The optimum pH was 5.6. The energy of activation was determined to be 7.03 kcal/mol in the temperature range 15-55 degrees C. Km for starch was 1.6 mg/mL in 50 mM sodium acetate buffer, pH 5.5. Thermal inactivation studies at 70 degrees C showed first-order kinetics with rate constant (k) equal to 0.005 min(-1). Mung bean alpha-amylase showed high specificity for its primary substrate starch. Addition of EDTA (10 mM) caused irreversible loss of activity. Mung bean alpha-amylase is inhibited in a non-competitive manner by heavy metal ions, for example, mercury with a Ki of 110 microM. Homology modelling studies with mung bean alpha-amylase using barley alpha-amylases Amy 1 and Amy 2 as templates showed a very similar structure as expected from the high sequence identity. The model showed that alpha-amylase from mung beans has no sugar-binding site, instead it has a methionine. Furthermore, instead of two tryptophans, it has Val(277) and Lys(278), which are the conserved residues, important for proper folding and conformational stability.  相似文献   

13.
Mung bean CYP90A2 is a putative brassinosteroid (BR) synthetic gene that shares 77% identity with the Arabidopsis CPD gene. It was strongly suppressed by chilling stress. This implies that exogenous treatment with BR could allow the plant to recover from the inhibited growth caused by chilling. In this study, we used proteomics to investigate whether the mung bean epicotyl can be regulated by brassinosteroids under conditions of chilling stress. Mung bean epicotyls whose growth was initially suppressed by chilling partly recovered their ability to elongate after treatment with 24-epibrassinolde; 17 proteins down-regulated by this chilling were re-up-regulated. These up-regulated proteins are involved in methionine assimilation, ATP synthesis, cell wall construction and the stress response. This is consistent with the re-up-regulation of methionine synthase and S-adenosyl-L-methionine synthetase, since chilling-inhibited mung bean epicotyl elongation could be partially recovered by exogenous treatment with DL-methionine. This is the first proteome established for the mung bean species. The regulatory relationship between brassinosteroids and chilling conditions was investigated, and possible mechanisms are discussed herein.  相似文献   

14.
介绍一种用像增器接收荧光图像的高灵敏度荧光显微镜,相对于普通荧光显微镜的灵敏度提高了4×104倍,并用宽量程微光光亮度计对仪器的微弱成像性能进行了实验标定,得到了图像采集数据和图像发光强度的线性数量关系。高灵敏度荧光显微镜在给出细胞荧光图像的同时,可以给出图像上每一像元的发光强度和细胞平均发光强度,仪器对图像细微变化的判断能力远大于人眼直接观察图像。高灵敏度荧光显微镜可应用于研究细胞中荧光物质在细胞生理过程中的分布变化和发光强度变化。使用此仪器已得到了光敏竹红菌甲素(HA)在Hela细胞(人体子宫癌细胞)中的分布图像和更为直观的三维显示图形,以及加入HA后Hela细胞受到强先照射后的细胞损伤图像。  相似文献   

15.
Mung bean peel polysaccharides are one of the main active components in mung bean peel. Acetylated mung bean peel polysaccharides were prepared by extracting and acetylating them, and characterized by infrared and ultraviolet methods to preliminarily understand the structural characteristics and activity of acetylated mung bean peel polysaccharides. Acetylation modification can improve the structure of polysaccharides, thereby causing changes in their properties. The product obtained after acetylation modification exhibited new characteristic absorption peaks at 1732 cm−1, and the scavenging ability of hydroxyl radicals was improved. Therefore, acetylation modification of mung bean peel polysaccharides could enhance the activity by improving the structure, which provided an experimental basis for the application of mung bean peel polysaccharides.  相似文献   

16.
Mung bean was investigated as a novel source of lipoxygenase in the natural production of the green-note aroma compound hexanal. Lipoxygenase extracted from mung bean catalyzed the oxidative reaction of linoleic acid, after which the intermediate hydroperoxide compound was split via green bell pepper hydroperoxide lyase to produce hexanal. In comparison to soybean lipoxygenase, mung bean lipoxygenase was found to be a good substitute as it produced 15.4 mM (76% yield) hexanal while soybean gave 60% yield. The mung bean pH profile comprised a wide peak (optimum pH 6.5) representing lipoxygenase-2 and lipoxygenase-3 isozymes, whereas two narrower peaks representing lipoxygenase-1 and lipoxygenase-2/3 isozymes were observed for soybean (optimum pH 10). Extraction at pH 4.5 was preferred, at which specific lipoxygenase activity was also the highest.  相似文献   

17.

Background  

All living organisms emit spontaneous low-level bioluminescence, which can be increased in response to stress. Methods for imaging this ultra-weak luminescence have previously been limited by the sensitivity of the detection systems used.  相似文献   

18.
Evaluation of hepatoprotective activity of legumes.   总被引:3,自引:0,他引:3  
Mung bean, adzuki bean, black bean and rice bean are foods and folk medicines of Taiwan. We evaluated the effects of various water extract concentrations (100, 500 and 1000 mg/kg body wt.) and silymarin (25 mg/kg body wt. on acetaminophen-induced liver injury by measuring serum glutamate-oxalate-transaminase (sGOT) and serum glutamate-pyruvate-transaminase (sGPT) activities in rats. The results showed that the sGOT and the sGPT activities, increased by APAP, were decreased significantly (P < 0.05) through treatment with inceasing amounts up to 1000 mg/kg body wt. of the exracts. In particular, the mung bean aqueous extract showed the best hepatoprotective effect on APAP-induced hepatotoxicity. The pathological changes of liver injury caused by APAP improved by the treatment with all of the legume extracts, which were compared to silymarin as a standardized drug. In addition to these results, the extract of mung bean acted as a potential hepatoprotective agent in dietary supply.  相似文献   

19.
It has been shown that peroxymonocarbonate ion (HCO(4) (-)) is a potent oxidant. In this study, a flow-injection system was developed in order to prepare on-line HCO(4) (-) ion and the optimum conditions for the on-line preparation of HCO(4) (-) were studied in detail. We used 99% (13)C-enriched NaHCO(3) to examine peroxymonocarbonate by (13)C-NMR at 25 degrees C. An ultra-weak chemiluminescence (CL) was observed after mixing H(2)O(2) and sodium bicarbonate in an organic co-solvent that can accelerate the formation of HCO(4) (-) ion. When lanthanide inorganic coordinate complex, Eu(II)-EDTA, was added into this HCO(4) (-) system, the CL intensity was significantly enhanced. The CL mechanism was investigated by various methods. The experimental results indicate that peroxymonocarbonate oxidizes Eu(II) to Eu(III) and produces singlet oxygen; meanwhile, the energy originating from dimers of singlet oxygen is accepted by the Eu(III)-EDTA(-) complex. The excited Eu(III) ions undergo radiative deactivation and emit CL.  相似文献   

20.
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