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以体外培养的人正常肝细胞(LO2)和人胚肾细胞(HEK293)为模板,用MTT比色法研究了玉米赤霉烯酮对以上两种细胞株的毒性作用,结果表明,在所测浓度范围内,玉米赤霉烯酮对这两种细胞的抑制率随其作用浓度的增加而增强,而其作用浓度到达一定程度时,玉米赤霉烯酮对这两种细胞的抑制率保持在一定的范围内不再增加。实验结果证明在2.50μg/mL和1.25μg/mL的最高浓度下,玉米赤霉烯酮对人正常肝细胞(LO2)和人胚肾细胞(HEK293)的抑制率分别为86.61%和67.06%,可见其肝毒性和肾毒性明显。 相似文献
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计算机分子对接是模拟受体和底物之间通过能量匹配和几何匹配而相互识别的过程。其被广泛运用于虚拟筛选活性物质以及初步判断分子活性和毒性等领域,并对我们进行实体分子活性毒性试验起到了重要的指导作用。分子动力学方法ADMET(吸收,分配,代谢,排泄和毒性)是当代药物设计和药物筛选中十分重要的方法。早期ADMET性质研究主要以人源性或人源化组织功能性蛋白质为"药靶",体外研究技术与计算机模拟等方法相结合,研究目标分子与体内生物物理和生物化学屏障因素间的相互作用。在本实验中我们利用计算机分子对接以ADMET分析软件,对脱氧雪腐镰刀菌烯醇(呕吐毒素)以及其降解产物进行计算机分子模拟分析,初步模拟呕吐毒素及其降解产物的毒性强弱,对呕吐毒素降解研究有重要的辅助作用。 相似文献
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利用计算机模拟分子对接技术探究粮食中黄曲霉毒素的毒理效应 总被引：1，自引：0，他引：1
黄曲霉毒素是一类化学结构类似的小分子化合物,均为二氢呋喃香豆素的衍生物,主要存在于土壤、动植物和各种坚果中,是霉菌毒素中毒性最大,对人类健康危害极为突出的一类霉菌毒素,而黄曲霉毒素的毒理机制始终不是很明确。计算机分子对接是模拟受体和底物之间通过能量匹配和几何匹配而相互识别的过程,其被广泛运用于虚拟筛选活性物质以及初步判断分子活性和毒性等领域,并对我们进行实体分子活性毒性试验起到了重要的指导作用。利用计算机分子对接软件Discovery Studio 3.1client,将6种常见黄曲霉毒素分子B1、B2、M1、M2、G1、G2与其具有强亲和性的蛋白进行虚拟对接实验,而这些蛋白在细胞凋亡、激素代谢、免疫抑制以及消化系统功能方面有重要的作用。通过本实验能够初步模拟黄曲霉毒素分子毒性作用位点,对于其毒理机制研究有重要的辅助作用。 相似文献
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玉米赤霉烯酮与冬小麦的生长与发育 总被引：8，自引：1，他引：7
实验采用酶联免疫法分析了冬小麦（燕大1817）（Triticum aestivum L.Yan Da 1817）在不同条件（低温、短日或长日）下内源玉米赤霉烯酮（Zearalenone, 以下简称ZEN）的动态变化,并通过在不同时期外施ZEN探讨外源ZEN对冬小麦生长发育的影响。结果表明,ZEN可能是冬小麦生长与发育的重要调节物质之一。短日诱导可以代替低温春 相似文献
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《粮食储藏》2018,(6)
通过样品采集和制备,对5个样本的呕吐毒素、玉米赤霉烯酮、黄曲霉毒素B1含量进行检测和分析。实验结果表明,同一玉米样品同一生霉粒其含量与呕吐毒素、玉米赤霉烯酮、黄曲霉毒素B1含量呈正相关;同一地区玉米真菌毒素整体侵染程度基本相同,不同地区三种真菌毒素侵染程度不同,不同生霉粒包含的真菌毒素类型不同,真菌毒素具有地域性;陕西地区2017年黄曲霉毒素B1污染基本为零;同一小麦样品不同梯度病斑粒含量与呕吐毒素呈正相关,不同地区小麦呕吐毒素可能差别很大,赤霉病粒对小麦呕吐毒素的影响非常大。因此,不能简单由玉米、小麦的外观或者生霉粒、病斑粒含量判断真菌毒素含量的高低,但是根据同一样品中同一生霉粒、病斑粒其含量与真菌毒素呈正相关性,可以在收获季节,分地区采集样品,检测完好粒与生霉粒或者病斑粒真菌毒素的侵染情况,寻找合理控制点,通过收购质量指标指导对相关监测卫生指标的把控,辅助粮食质量安全的监测,尽力解决目前现场收购时的质量安全风险漏洞。 相似文献
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Jens Jensen 《Euphytica》1979,28(1):47-56
Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans. 相似文献
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Hongyan WEI Jian ZHOU Jinguang LU Jingzheng SONG Qiongxi YU Zhihong JIANG 《Medicinal Plant》2019,(6):27-29
[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol... 相似文献
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Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed. 相似文献
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Richard N. Lester 《Euphytica》1989,44(1-2):125-132
Summary An hypothesis is developed that the rapid change from wild plants into domesticated crops principally involves the selection of alleles with non-functional gene products which leads to reduced control of the highly integrated metabolism and morphogenesis previously accumulated by lengthy natural selection. Such disturbance of the genome produces altered physiological and morphological development which, although deleterious in nature, serves mankind better and has been selected. 相似文献
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B. Julier P. Guy C. Castillo-Acuna G. Caubel C. Ecalle M. Esquibet V. Furstoss C. Huyghe C. Lavaud A. Porcheron P. Pracros G. Raynal 《Euphytica》1996,91(2):241-250
Summary Twenty-five lucerne populations of the Medicago sativa complex, which were either diploid or tetraploid and wild or cultivated, were analysed for their resistance to four different fungal diseases and to stem nematode. Forage quality, including stem digestibility and saponin content, was also tested.Populations varied in susceptibility to the diseases caused by Colletotrichum trifolii, Verticillium albo-atrum, Sclerotinia trifoliorum and Pseudopezizza medicaginis, and to the nematode Ditylenchus dipsaci. Except for Sclerotinia rot, sativa and falcata subspecies differed in susceptibility, but this grouping of populations did not account for the full range of variation among them. However, the resistance to P. medicaginis was much lower in the sativa than in the falcata populations.Populations also varied significantly in stem fiber content and digestibility. Stem digestibility was negatively correlated to forage yield. Wild sativa and falcata populations had lower fiber content and higher digestibility than cultivated sativa populations. The medicagenic acid was the sapogenin responsible for the anti-nutritional effect of the lucerne measured by the yellow mealworm larvae Tenebrio molitor. The medicagenic acid content was lowest for the pure sativa populations, highest for the pure falcata populations, and intermediate for the French sativa varieties that have some traits originating from falcata germplasm. Some populations could be used in breeding programs to improve disease and nematode resistance, and forage quality. 相似文献
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In order to explore the pharmacological effects of active components of Gastrodiae Rhizoma on the central nervous system,through consulting related literatures,... 相似文献
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[Objectives]The purpose of this study was to investigate the effects of Pb on rhizosphere soil enzyme activity and chemical constituents of Achyranthes bidentat... 相似文献
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不同P-Zn配比对小麦幼苗微量元素营养的影响 总被引：2，自引：0，他引：2
采用了螯合-缓冲营养液培养方法对小麦进行了苗期培养试验,在3个P水平(0,0.6,3.0 mmol/L)和3个Zn水平(0,3,30 μmol/L)的完全组合下对小麦苗期生长及Zn、Fe、Cu、Mn营养进行了研究,旨在为小麦微肥施用提供理论依据.结果表明,P、Zn的正常供应促进了小麦生长,二者的缺乏与过量均会抑制小麦发育,且这种影响在冠部表现得更为明显.在小麦苗期,Zn与Cu的吸收存在明显的拮抗作用,但供Zn则促进了Zn和Cu的转运,而Mn转运则受到了抑制;过量供Zn时,大量Zn被转运到冠部,同时明显抑制了(Fe+Cu+Mn)的吸收总量;P的供应显著地抑制了Fe的吸收,但P的供应提高了Zn、Cu、Mn的转运率;P、Zn在对Zn与Fe、Cu、Mn间吸收竞争的影响中,Zn本身的影响要比P的影响更为明显,供Zn明显促进了小麦幼苗对Zn的吸收;在小麦幼苗冠部,Zn与Fe的竞争中,供P利于Zn的吸收,缺P则利于Fe的吸收;而Zn与Cu以及Zn与Mn间的竞争中,缺磷时利于Zn的吸收,供磷后则利于Cu和Mn的吸收.总之,小麦幼苗Zn、Fe、Cu、Mn营养中,P、Zn的不同配比会不同程度地改变Zn与Fe、Cu、Mn的协同或拮抗效应. 相似文献
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Summary
Glycine tabacina (Labill.) Benth. is a wild perennial species related to the cultivated soybean, G. max (L.) Merr. It is composed of diploid (2n=40) and tetraploid (2n=80) cytotypes. Currently, to differentiate the cytotypes, plants are grown out in the greenhouse and chromosome counts made on pollen mother cells. It is a laborious and time consuming process. The objective of this study was to determine whether electrophoretic techniques could be utilized to separate the cytotypes. Electrophoretic examination of seven isozyme systems from seed of 67 G. tabacina accessions revealed banding patterns that could be used to differentiate between diploid and tetraploid cytotypes in the species. Among the tetraploid accessions, the number of bands observed were always greater than the diploids. Some tetraploid banding patterns consisted of bands similar to the diploid tabacina and/or additional bands previously identified in other Glycine species. The patterns of isozyme multiplicity and variation in the tetraploid tabacinas suggests more than one mode of origin for the tetraploids. 相似文献
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Summary Some photosynthetic characters as-leaf anatomy, leaf photosynthetic rate and CO2 compensation pointdistinguishing C3 and C4 plants and physiological characters as leaf area ratio, nitrogen content, leaf stem ratio and total shoot-to-root and deep root-to-shoot ratios have been studied in rice × sorghum and rice × wheat hybrids. Rice × sorghum 1. has lower values of photosynthetic rate, leaf nitrogen, total root and deep root-to-shoot ratio and CO2 compensation point as of rice parent where as, rice × sorghym 2. is superior in all these characters. Both hybrids lack kranz anatomy. Though both rice × sorghum hybrids show characters of C3 rice plant but rice × sorghum 2. has improved drought tolerance and leaf characters in relation to yield. Rice × wheat hybrid have higher assimilatory area and higher total root-to-shoot ratio. Grains of rice × wheat hybrids are identical to rice grain. However, as grains of rice × wheat hybrid does not contain seed coat, it could be exploited as novel rice germplasm after improvement.Abbreviations T
CO2 compensation point
- T21
CO2 compensation point at 21% O2
- T2
CO2 compensation point at 2% O2
- dR/sR
deep Root-to-shoot Ratio
- LAR
Leaf Area Ratio
- CER
photosynthetic rate
- TR/SR
Total Root-to-Shoot Ratio 相似文献