8 resultados para SCHI


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大豆 (Glycine max (L.) Meer.)是人们日常生活中不可缺少的食品,也是一种非常重要的油质、蛋白资源。目前根据大豆种子吸胀阶段对低温敏感性的不同,可将其划分成3种生态型:低温非敏感型、低温敏感型及中间型。对于低温非敏感型的种子来讲,4℃下吸胀24小时对其发芽率影响很小,而敏感型种子萌发率不超过5%。我国属于温带大陆性气候,大豆播种后由于温度波动而造成一部分种子不能萌发,最终导致减产甚至绝产的现象普遍存在。高产是育种工作的主要目标,提高逆境胁迫的适应能力是高产的前提和基础,所以从分子角度研究种子吸胀非常必要,一方面能够挖掘新的基因资源,另一方面为今后育种工作提供必要的理论依据。 本试验以此为立足点,低温吸胀非敏感型大豆品种 (Z22)为材料,利用cDNA-AFLP方法及蛋白质技术分离与低温吸胀相关的基因及蛋白,得到结果如下: 第一,本试验成功的分离出4个受低温诱导的基因,半定量RT-PCR方法进一步验证了这4个基因在种子吸胀24小时内受低温诱导。 第二,利用RACE方法成功的得到2个完整的全长基因,在NCBI数据库中查找后发现其中1个基因为新基因,命名为SCHI基因 (SCHI:Soybean chilling-induced gene)。SCHI全长为390bp,编码分子量大约为14.2KD的蛋白;另外一个基因是已知基因,其同源序列已经在其他的物种中得到分离。由于此基因与核糖体蛋白L34高度同源,所以把把这个基因命名为SOL34 (Soybean L34)。 第三,利用半定量RT-PCR方法对基因表达模型进行分析,结果表明:SCHI在种子低温吸胀18~24小时期间诱导表达量最高,而当种子低温吸胀24小时后转入常温下,其表达量在常温下18小时左右迅速下降;ABA (100μM)、PEG (30%,10000)及NaCl (250mM)能够诱导SCHI的表达,在诱导表达量上,ABA和PEG诱导效果最明显,而NaCl能够微弱的诱导此基因表达;对不同生态型的大豆品种而言,低温吸胀过程中,SCHI在非敏感型种子中的表达量高于敏感型种子,但非敏感型和中间型之间没有差别;另外,SCHI在大豆胚轴中是诱导型表达,在叶片和根尖中则是组成型表达。SOL34的表达在萌发前24小时内被低温诱导,但在不同生态型之间没有差别。SOL34在胚轴和根尖中受低温诱导,在叶片中是组成型表达。 第四,SCHI能够在原核生物中表达出相应蛋白,诱导表达蛋白的分子量在26-29KD,大约为理论值的2倍,说明在大肠杆菌中被表达的蛋白以2聚体形式存在。另外低温试验结果表明SCHI能够提高菌落忍耐短时间-20℃低温的能力。 第五,利用双元表达载体把SCHI转入拟南芥植株,经过低温、干旱和盐胁迫后,转基因植株的成活率均高于野生型植株。超表达SOL34的拟南芥植株降低了对低温的耐性;而抑制拟南芥中L34的表达反而提高了植株对低温的抗性。 第六,本试验利用蛋白质等有关试验检测了大豆种子低温吸胀时蛋白质发生的变化。从吸胀 (4℃和22℃下24h)后的大豆胚轴中成功鉴定出上调蛋白点25个,下调蛋白点15个。其中有参与能量代谢反应 (占10%,例如柠檬酸脱氢酶和苹果酸脱氢酶等)、细胞生长与分裂相关反应 (20%,例如LEA蛋白和种子成熟蛋白PM26)、胁迫反应 (10%,如乙醇脱氢酶)、种子宿命和贮藏蛋白 (20%,大豆球蛋白)等蛋白在此过程中发生了变化,暗示种子萌发前期低温吸胀过程中多种代谢发生变化。细胞生长变缓、能量代谢增强、胁迫代谢蛋白的高表达以及贮藏蛋白降解速度减慢等变化都有利于种子在吸胀过程中度过低温环境,为以后的生长作好准备。

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The Island Lake greenstone belt is one of the major Archean supracrustal exposures in the northwestern part of the Superior Province of the Canadian Shield. This belt is subdivided into two units: 1) a lower sequence characterised by pillowed to massive, locally pyroclastic, basalt to andesite with a thin central zone of felsic derivatives, all of which are interbedded with and overlain by thick sequences of turbidite facies rock; 2) the upper unit which consists of thick stratified conglomerate overlain by thickly bedded arkose and feldspathic greywacke. Reconnaissance sampling traverses were completed across both the strike of the belt and along its margins with adjacent granitoids. Most of the belt is within the greenschist metamorphic f acies with amphibolite facies occurring in certain areas near t he margins. A post-tectonic, low pressure thermal event may be responsible for the development of a unit of cordierite schi s t which stretches southeastwards from the east end of Cochrane Bay. Volcanism is cyclical in nature changing from tholeiitic to calc-alkaline. There is a general progression in the character of the lavas from mafic t o felsic with stratigraphic height. Chemica l d a ta sugges t that h i gh level fractionation of a mantle- derived ' dry' magma i s t he s ource of the thole i iti c lavas. Contamination of this magma with 'we t' sia l and subsequent fractionation may be r esponsi b l e for the calcalkaline phases .Observations of stratigraphic relationships (in particular the contact between the supracrustals and the granitoids) coupled with the metamorphic and chemical studies, allow the construction of a preliminary model for the evolution of the Island Lake greenstone belt. The following sequential development is suggested: 1) a platform stage characterised by the subaqueous effusion of mafic to intermediate lavas of alternating tholeiitic and calc-alkaline affinities; 2) an edifice stage marked by the eruption of felsic calc-alkaline rocks; 3) an erosional stage characterised by the deposit~on of thick sequences of turbidite facies rocks; 4) the impingement of granitic masses into the margins of the greenstone belt, which was probably related to a downward warping of the supracrustal pilei 5) the erosion of sialic massifs surrounding and within the greenstone belt and of early supracrustal piles, to give the clastic upper unit.

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: Los métodos imagenológicos para evaluar los nódulos tiroideos han sido motivo de estudio en las últimas décadas, especialmente la ecografía sobresale sobre las otras modalidades diagnósticas por su accesibilidad, portabilidad, y seguridad. A pesar de ello, las características ecográficas de cada nódulo han sido objeto de controversia en cuanto a su potencial detección de malignidad o benignidad. Se presenta un estudio de concordancia entre el estudio citopatológico y la ecografía para la caracterización nódulos tiroideos de naturaleza maligna y benigna, y su análisis de pruebas diagnósticas. Metodología: Se realizó un estudio descriptivo de concordancia con estudio de pruebas diagnósticas anidado. Se escogieron todos los pacientes con nódulos tiroideos a quienes se les realizó ecografía y estudio citopatológico de la lesión y se estudiaron los hallazgos ecográficos para evaluar su potencial diagnóstico para malignidad. Se incluyeron un total de 100 pacientes con nódulos tiroideos potencialmente malignos. La concordancia entre la ecografía en modo B y el estudio citopatológico fue moderada (índice kappa 0.55). La característica con mayor potencial para detectar malignidad fue la presencia de Microcalcificaciones (sensibilidad 75%, especificidad 92%).

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Drawing on the reception of Noh drama by Ezra Pound and William Butler Yeats, the article analyses both the literary and cultural ‘translations’ of this form of Japanese theatre in their works, focusing on Yeats’s play At the Hawk’s Well (1917). I conceptualize ‘cultural translation’ as the staging of relations that mark a residual cultural difference. Referred to as ‘foreignizing’ in translation theory, this method enables what Erika Fischer-Lichte has termed a ‘liminal experience’ for the audience –– an effect Yeats intended for the performance of his play. It evokes situations in which opposites collapse and new ways of acting or new combinations of symbols can be tried out. Yeats’s play will be used to sketch how an analysis of relations could serve as a general model for the study of cultural transfer as cultural translation in general. Keywords: cultural translation, translation theory, performance, William Butler Yeats, Itō Michio, Ezra Pound, At the Hawk’s Well

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Studies were made of the glacial geology and provenance of erratic in the Shackleton Range during the German geological expedition GEISHA in 1987/88, especially in the southern and northwestern parts of the range. Evidence that the entire Shackleton Range was once overrun by ice from a southerly to southeasterly direction was provided by subglacial erosional forms (e.g. striations, crescentic gouges, roches moutonnées) and erratics which probably orriginated in the region of the Whichaway Nunataks and the Pensacola Mountains in the southern part of the range. This probably happened during the last major expansion of the Anarctic polar ice sheet, which, on the basis of evidence from other parts of the continent, occurred towards the end of the Miocene. Till and an area of scattered erratics were mapped in the northwestern part of the range. These were deposited during a period of expansion of the Slessor Glacier in the Weichselian (Wisconsian) glacial stage earlier. This expansion was caused by blockage of the glacier by an expanded Filchner ice shelf which resulted from the sinking of the sea level during the Pleistocene, as demonstrated by geological studies in the Weddell Sea and along the coast of the Ross Sea. Studies of the erratics at the edges of glaciers provided information about rock concealed by the glacier.

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t. 1. Notice sur le cardinal de Retz ... Portrait de Retz par Saint-Évremont. Portrait de Retz par La Rochefoucault. Mémoires du cardinal de Retz.--t. 2. Mémoires de Retz (cont'd)--t. 3. Mémoires de Retz (cont'd) Procès verbal de la conférence, faite à Ruel. Le trictrac. Lettre présentée au Sacré collége de la part du cardinal de Retz, pendant sa prison. Le courrier burlesque de la guerre de Paris. Sermon de Saint Louis, roi de France ... par J.F.P. de Gondi. La conjuration du comte Jean-Louis de Fiesque. Avis à M. le cardinal Mazarin, sur les affaires de M. le cardinal de Retz.--t. 4. Notice sur Guy Joli. Mémoires de Guy Joli.--t. 5. Mémoires de Guy Joli (cont'd) Mémoire concernant le cardinal de Retz ... par Claude Joli. Mémoires de la duchesse de Nemours.