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猿猴病毒40型大T 抗原對老鼠漿細胞和脾臟B 淋巴球抗體分泌的影響
No full text[[abstract]]建立一能分泌單一特殊抗體之B 淋巴球細胞株, 是研究抗體構造及功能中最重要事情
。目前用來製造B 淋巴球細胞株的方法中; 不管是用礦物油人為誘發產生之漿細胞瘤
或是用核融合所產生之副合瘤皆有其缺點。漿細胞瘤之遣傅性質不穩定, 且易造成所
產生之免疫球蛋白構造上的變異; 而融合瘤又容易造成染色體上的流失。基於以上之
缺點, 我們希望利用病毒之致癌基因來建立B 淋巴球細胞株。大T 抗原為猿猴病毒40
型早期基因區之產生, 目前已經知道只要有大T 抗原的穩定表現便足以造成寄主細胞
之轉型, 而使其變成一能不斷分裂生長之轉形細胞株。所以本論文之主要目的便希望
能借助猿猴病毒40型內大T 抗原之致癌基因的幫助, 而能成功地轉形老鼠脾臟B 淋巴
球, 使其成為一能不斷分裂且不斷產生單一特殊抗體之B 淋巴球細胞株。本論文分成
兩部分成兩部分, 在第一部分實驗中, 利用帶有大T 抗原基因之兩種質體(pSC和pSV1
) 轉形一能分泌IgA 抗體之MOPC-315漿細胞瘤, 以評估進入細胞內之大T 抗原是否會
影響細胞之生長及抗體之分泌。在第二部分實驗中, 便直接以帶有大T 抗原基因之兩
質體去轉形老鼠脾臟B 淋巴球, 而評估用大T 抗原轉形誘發產生B 淋巴球細胞株之可
行性。由實驗之初步結果證實: 經大T 抗原基因轉形過之MOPC-315細胞株, 其生長狀
錶和抗體分泌情形不受影響。隨後我們拿大T 抗原基因之質體轉形老鼠脾臟B 淋巴球
, 發現大T 抗原能成功地的轉形老鼠脾臟B 淋巴球且能不斷分泌IgM(μ、λ) 、IgG
(r 、λ)、IgA (a 、λ)抗體長達一個月時間。由此實驗之結果推論: (1) 、將pS
C 和pSV1兩質體做共同轉形所造成之效果, 較只有單一質體之效果好。(2) 、在T 淋
巴球conditional medium中具有轉形細胞生長所需之生長因子。(3) 、轉形細胞無法
穩定生長除了TCM 不足所造成外, 也可能因大T 抗原基因沒有穩定嵌入寄主細胞之染
色體上, 或是大T 抗原表現不穩定所造成。(4) 、在病毒轉形之實驗中, 經常會有轉
形一段時間後, 轉形細胞變大而死亡之現象發生。
[[alternative]]In vitro study on the regulation of human immunoglobulin production by dehydrepiandrosterone (DHEA)
No full text[[abstract]]金融創新與衍生性金融商品是80年代以來國際金融市場的新趨勢，其中認購權證便
是衍生性金融商品的一種。雖然發行認購權證在國外已是一個普遍的現象，然而國
內外學者卻顯少有人探討認購權證與其標的股票之關係。由於自民國85年來，外資
機構在海外發行台灣股票市場單一個股、類股、一籃子股票或是指數型之備兌認購
權證，對國內股市已造成相當之影響，又適逢台灣認購權證的掛牌上市，因此本研
究想藉此機會探討「認購權證之引入是否會對標的股票報酬率及其波動性造成影響
」; 以及對「認購權證報酬率與標的股票報酬率間是存在何種領先、落後與同期的
關係」作一實證之研究。
本研究以大華01、大華02、寶來01、寶來02及其標的股票為研究對象，利用GARCH(
1,l)模型及狀態空間模型來對上述的二個研究目的作分析，根據實證結果得到下列
結論:
一、研究目的一
( 一 )所有股票皆無發行效果; 除太電與太設有負的上市效果外，其餘10支股票皆
無上市效果。
( 二 )大部份股票的波動性並無顯著的改變，只有國巨與華新兩支股票因權證的發
行及茂矽困權證的上市，對股票報酬的波動性產生顯著性的負影響。
( 三 )不論是認購權證的發行或上市，對標的股票報酬率及其波動性的影響正負方
向與影響程度並不一致。
二、在研究目的二
( 一 )四支權證的報酬率與標的股票報酬率問的領先、落後關係並不一致。
( 二 )四支權證的報酬率與標的股票報酬率間存在顯著同期的正向影響關係。
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
脂多醣體誘發之巨噬細胞分泌素對老鼠B 淋巴球分泌A 形免疫球蛋白之調節作用
No full text[[abstract]]有關A 型免疫球蛋白分泌的調節, 多偏重T 淋巴球的探討, 至於巨噬細胞的影響則少
被提及。本實驗將老鼠腹腔巨噬細胞受脂多醣體刺激所產生的巨噬細胞分泌素, 加到
經脂多醣體處理的老鼠脾臟B 淋巴球, 結果七天後, 能使B 淋巴球分泌的A 型免疫球
蛋白增加二至九倍, 然而卻明顯掏B 淋巴球的增生。此種影響與轉型生長素β (TGF
β ) 對B 淋巴球生長及A 型免疫球蛋白分泌的作用相似。由於抗體型生長素β 抗
體有部分中和(41%) 巨噬細胞分泌素促進A 型免疫球蛋白分泌的功能, 故巨噬細胞分
泌素中促進A 型免疫球蛋白分泌的物質之一, 應為專型生長素β 。另有兩種巨噬細
胞產物prostaglandinE (PGE ) 及leucotriene B (LTB ), 亦屬免疫調節因子。
然而高濃度的PGE 和LTB 同時抑制B 淋巴球增生和A 型免疫球蛋白的分泌。故可能
與上述巨噬細胞分泌素的功能無關。此外, 為了瞭解巨噬細胞分泌素調節作用之胞內
機制, 三種巴知的胞內傅訊途徑與B 淋巴球生長和A 型免疫球蛋白分泌之關係亦被探
討。使用Ionophore A23187提高胞內鈣離子濃度, 或以forskolin 提高胞內cuclic-A
MP的濃度, 若施用的濃度較高, 則B 淋巴球的增生和A 型免疫球蛋白的分泌均受抑制
。以phorbol 12-myristate 13-acetate(PMA)直接活化protein kinase C, 雖然抑制
B 淋巴球的增生, 但不影響A 型免疫球蛋白的分泌。所以巨噬細胞分泌素調節A 型免
疫球蛋白的分泌, 不是透過這三種胞內傅訊途徑。本實驗肯定了巨噬細胞在A 型免疫
球蛋白分泌的調節上, 居重要的角色。此外, 巨噬細胞分泌素的作用, 是否涉及轉型
生長素β 以外的物質, 值得進一步研究。
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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