993 resultados para 165-998B


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本文以9 个芍药野生种(15 份种质)、104 个品种及2 个牡丹芍药组间杂种的花瓣为材料,利用液质联用技术鉴定了花瓣中的色素成分并探讨了芍药花色形成的化学机制和化学分类法。 结果表明,芍药花中主要含有5 种花青素,即芍药花素-3,5-二葡糖苷( peonidin-3,5-di-O-glucoside , Pn3G5G ); 矢车菊素-3 , 5- 二葡糖苷( cyanidin-3,5-di-O-glucoside , Cy3G5G ); 天竺葵素-3 , 5- 二葡糖苷( pelargonidin-3,5-di-O-glucoside , Pg3G5G ); 芍药花素-3- 葡糖苷(peonidin-3-O-glucoside,Pn3G)和矢车菊素-3-葡糖苷(cyanidin-3-O-glucoside,Cy3G)。此外,3 种微量的花青素首次在芍药中发现:它们分别为芍药花素-3-葡萄糖-5-阿拉伯糖苷(peonidin-3-O-glucoside-5-O-arabinoside,Pn3G5Ara)、矢车菊素-3- 葡萄糖-5- 半乳糖苷( cyanidin-3-O-glucoside-5-O-galactoside ,Cy3G5Gal)和天竺葵素-3-葡萄糖-5-半乳糖苷(pelargonidin-3-O-glucoside-5-Ogalactoside,Pg3G5Gal)。特征花青素Cy3G5Gal 和Pg3G5Gal 仅在新疆芍药(Paeonia anomala L.)及其亚种川赤芍(P. anomala subsp. veitchii(Lynch) D. Y.Hong & K. Y. Pan)中被检测出来,表明它们属于同一个种。Pn3G5Ara 仅存在于欧洲的野生芍药花瓣中,表明中国野生芍药和欧洲芍药的花青素代谢途径不同。 芍药花瓣中主要含有11 种花黄素,均为黄酮醇类物质。包括栎精-3,7 二葡糖苷( quercetin-3,7-di-O-glucoside )、山奈酚-3 , 7 二葡糖苷(kaempferol-3,7-di-O-glucoside)、异鼠李素-3,7 二葡糖苷(isorhamnetin-3,7-di-Oglucoside)、栎精-3-O-(6”-没食子酰基)-葡糖苷 [quercetin-3-O-(6”-O-galloyl)-glucoside] 、栎精-3- 葡糖苷( quercetin-3-O-glucoside )、山奈酚-7- 葡糖苷( kaempferol-7-O-glucoside )、山奈酚-3-O- ( 6”- 没食子酰基) - 葡糖苷[kaempferol-3-O-(6”-O-galloyl)-glucoside]、异鼠李素-3-O-(6”-没食子酰基)-葡糖苷 [isorhamnetin-3-O- ( 6”-O-galloyl ) -glucoside] 、山奈酚-3- 葡糖苷(kaempferol-3-O-glucoside)、异鼠李素-3-葡糖苷(isorhamnetin-3-O-glucoside)和山奈酚-丙二酰葡糖苷(kaempferol-malonyl-glucoside)。此外,查耳酮在黄色的栽培品种‘黄金轮’和牡丹芍药组间杂交种‘伊藤杂种’中首次被检测到。其化学结构为查耳酮-2’-葡糖苷(chalcononaringenin 2’-O-glucoside),它是花瓣表现出黄色的主要色素,它与黄色牡丹野生种‘滇牡丹’(P. delavayi Franchet)花瓣中主要黄色色素成分一致。 通过对所有芍药野生种和栽培品种的色素分析,研究发现花青素是芍药花瓣中主要的色素,其中Pn3G5G 是花瓣中含量最高的花青素苷,其次为Cy3G5G。3G 型糖苷仅在少数品种中检测出来。此外,黄酮醇是芍药花瓣中重要的辅助色素。山奈酚苷是花瓣中含量最高的黄酮醇类,其次是栎精。 多元线性回归分析的结果表明,芍药花色的形成主要与花瓣中Pn3G5G、Cy3G5G 和Pg3G5G 的含量及总花青素量(TA)有关。根据8 种花青素结构与花色组成,将国内的野生种和大部分品种进行了化学分类:所有样本聚成3 大类,聚类后的树状图与其花色、花色素组成数据相一致,直观反映了野生种和栽培品种花色形成的化学背景和表型相似性程度。 芍药成色机理和化学分类的初步研究,对芍药新花色育种具有重要意义:芍药鲜红色花的育种中,育种亲本应具有高的Cy3G 含量、低的辅助色素效应指数。选育深紫色花或紫黑色花的品种,亲本应具有高的Pn3G5G 含量和低的Pg3G5G 含量。

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The feasibility of using AlGaInAs lasers for high-speed modulation at high temperatures was evaluated and compared with performance of GaInAsP devices. Both drift-diffusion and rate equation simulation were involved so that the temperature dependence of material parameters was found in terms of overall dynamic performance. Differential gain was estimated by means of drift-diffusion simulations.

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A technique to measure wall flow variation in Diesel Particle Filters (DPFs) is described. In a recent paper, it was shown how the flow distribution in DPFs could be measured in a non-destructive manner. This involved measuring the progressive dilution of a tracer gas introduced at the "outlet" channel upstream end. In the present paper, a significant further improvement to this technique is described, in which only a single probe is required, rather than the two of the previous technique. The single, traversable, probe consists of a controllable flow sink, and slightly downstream, a tracer gas supply. By controlling the sink flow rate such that a very small concentration of tracer gas is aspirated into it, the total flow up to that location in the channel is determined. Typical results showing the axial variation in the wall flow for known wall blockage cases are presented. It is suggested that this technique could be used to interpret the soot loading in the filter channels in a non-intrusive way.

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One of the key sectors of fisheries research is assessment and exploration which should have as main goal the support to the fishing industry: analyzing the effects of fishing on stocks, determining the potential stock to be exploited and the formulation of rules for an appropriate exploitation and preservation of resources. In this paper the author intends to analyze some aspects of the investigation in support to fishery management.

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Marine by-products coming under the ancillary products group found many applications in pharmaceutical and industrial sectors. Although many of these products are fetching very high price at the export market, adequate statistics regarding their current production, marketing and utilisation is lacking. The present analysis deals with the production potential, level of exploitation, uses, export growth rate and potential for the future of some of these marine by-products. The analysis revealed that an estimated quantity of 205 t. of shells, 10 t. of gastropod operculum, 4,932 t. of shark liver oil and 4,384 t. of shark cartilage could be produced annually in India with the current landings. The production potential of chitin is estimated as 3,560 t. from shrimp shell wastes and 1,354 t. from crab shell wastes. The high unit value of different products clearly indicates the scope for their development by evolving appropriate utilisation and marketing strategies.

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通过分离纯化棕点湍蛙(Amolops loloensis)皮肤分泌液中的生物活性物质,得到有促胰岛素释放活性的分离峰,并鉴定其结构.采用葡聚糖Sephadex G-50凝胶层析和反相高效液相(RP-HPLC)等手段对棕点湍蛙皮肤分泌液进行分离纯化,利用胰岛素释放实验进行活性检测,Edman降解法测定活性峰的氨基酸序列,反转录法构建cDNA文库并克隆其基因.得到一个具有显著的促胰岛素释放活性的十六肽,测得其氨基酸序列为:FMPIvGKsMSGLSGKL-NH2,命名为amolopin-1.由cDNA(开放阅读框为192bp)推导的氨基酸一级结构显示,其前体由64个氨基酸残基(aa)组成,包括高度保守的信号肽(22aa),酸性肽以及成熟肽.经过数据库序列比对,从棕点湍蛙皮肤中得到一个新的促胰岛素释放肽,进一步分析其作用机理和药代动力学,极有可能得到一个新的治疗糖尿病的降糖药物.

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本发明涉及一种大蹼铃蟾抗微生物肽及其制备方法和其基因,属于生物医学领域。抗微生物肽为从中国两栖类动物大蹼铃蟾(Bombina maxima)皮肤分泌物中分离得到的一种单链多肽,分子量2840,等电点983,多肽氨基酸全序列一级结构为:NH2-SIGAKILGGVKTFFKGALKELASTYLQ-NH2。制备方法是收集大蹼铃蟾皮肤分泌物,离心去除沉淀、冷冻干燥后,经离子交换、高压液相反相柱层析分离纯化后得到。编码抗微生物肽的基因由663个核苷酸组成,其中编码成熟抗微生物肽为第165-245位核苷酸。抗微生物肽具有广谱和显著的抑制细菌和真菌生长作用。抗微生物肽基因作为基因工程制备抗微生物肽的应用。

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Phytoplankton cell count, percentage composition and species diversity at 4 locations of different depth contours in the coastal waters of Mangalore, west coast of India were studied for a period of 8 months. A total of 27 genera of phytoplankton were recorded from the area of which 20 belonged to diatoms, 6 /dinoflagellates and 1 blue-green algae. On an average the population density was higher at 4 m depth contour (280.48xl04 cells/m3 ) than 8m depth contour (97.79xl04 cells/m3 ). The plankton cell density in the present study is much higher than the earlier observations made elsewhere which might be due to intense blooming of Chaetoceros, Cosctnodiscus, Ceratium, Dinophysis and blue-green algae along this coast during the study period.

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A variety of synthetic fibres are at present in use as fishing gear material, the earliest one being the polyvinyl chloride group introduced for traps in 1936 (von. Brandt 1957). Since then synthetic fibres became increasingly popular among the advanced fishing nations of the world. The latest synthetic fibre which has been successfully used in fishing is polypropylene developed in Italy in 1954.

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The distribution of pantothenic acid in free and bound forms in various fish species is reported. It is observed that the fish muscle contains on an average about 12.0µ g pantothenic acid per g. About 60% of the pantothenic acid is present in the bound form as coenzyme A in the fish skeletal muscle.

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NCp7在HIV-1生活周期中多个步骤发挥重要的核酸分子伴侣作用.抑制NCp7的功能可阻断HIV-1复制.NCp7含有两个高度保守的锌指结构,对NCp7的功能起决定性作用.锌指结构突变将导致HIV-1丧失感染能力.NCp7抑制剂可望成为下一代不容易产生耐药突变的抗HIV-1药物.本文就NCp7抑制剂目前的研究进展作简略综述.

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Recent studies examining adaptation to unexpected changes in the mechanical environment highlight the use of position error in the adaptation process. However, force information is also available. In this chapter, we examine adaptation processes in three separate studies where the mechanical environment was changed intermittently. We compare the expected consequences of using position error and force information in the changes to motor commands following a change in the mechanical environment. In general, our results support the use of position error over force information and are consistent with current computational models of motor learning. However, in situations where the change in the mechanical environment eliminates position error the central nervous system does not necessarily respond as would be predicted by these models. We suggest that it is necessary to take into account the statistics of prior experience to account for our observations. Another deficiency in these models is the absence of a mechanism for modulating limb mechanical impedance during adaptation. We propose a relatively simple computational model based on reflex responses to perturbations which is capable of accounting for iterative changes in temporal patterns of muscle co-activation.

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A study was conducted on the shelf-life of rotary and solar tunnel dried SIS products under different packaging and storage conditions. Organoleptically dried products were found in good condition after a storage period of 60 days in ambient and chilled conditions. The moisture content, TVB-N value and bacterial load slightly increased during 60 days of storage in ambient and chilled conditions. The changes in moisture content and bacterial load were faster in ambient temperature than in chilled storage condition whereas changes in TVB-N value was higher in chilled condition than in ambient temperature. The initial moisture content was in the range of 13.71% to 22.84%. After 60 days of storage in ambient and chilled condition the moisture content of dried products was in the range of 15.09% to 25.11% and 14.49% to 25.01%, respectively. The initial TVB-N value was in the range of 10.64 to 17.52 mg/100g and after 60 days of storage in ambient and chilled condition, TVB-N value was in the range of 29.00 to 34.82 mg/100g and 31.41 to 39.11 mg/100g, respectively. The initial bacterial load was in the range of 1.91x10 super(8) to 2.84x10 super(8) and after 60 days of storage in ambient and chilled condition, the bacterial load was in the range of 6.2x10 super(8) to 1.8x10 super(9) and 5.75x10 super(7) to 5.05x10 super(8) CFU/g, respectively. The results of the present study indicated that it is necessary to store high quality dried products in sealed packed in chilled condition to ensure good quality up to a certain period of time.

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Dendritic cells (DCs) play a pivotal role in linking the innate immunity and acquired immunity in responses to pathogen. Non-human primates such as Chinese Rhesus Macaque (CRM) are the favorable models for preclinical study of potential therapeutic drugs,