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Immunological, anti-tumor and antioxidant activities of phycocyanin from marine Synechococcus sp.
No full text藻藍素是藍綠藻中的主要成分，為一水溶性的蛋白，具有多種生理藥物活性特性。本論文實驗是探討海洋聚球藻藻藍素的免疫、抗癌及抗氧化活性，以評估未來應用的潛力。大量培養聚球藻後，以離心方式濃縮細胞，並予以冷凍乾燥備用。將乾燥的藻細胞以液態氮研磨後，溶於磷酸塩緩衝食鹽水，接著利用超音波將細胞壁打破。藻藍素粗萃取液在35-80% 硫酸銨飽和濃度下沉澱。本論文實驗採用雙管柱層析方法：陰離子交換層析管柱層析和石灰岩層析管柱，純度比值A620/A280為4.9，回收率為35%。所得之藻藍素以原態電泳和SDS-PAGE電泳分析其純度，再以Sephadex S-200層析管柱估算出藻藍素分子量為128 kDa。
將所得的藻藍素對老鼠巨噬細胞及人類癌細胞做體外活性檢測，以評估其對免疫能力及抑制腫瘤細胞的能力。藻藍素濃度為65 μg/ml時，可以刺激巨噬細胞生長提高增殖達38%。藻藍素也具有抑制癌細胞生長的活性，濃度為65 μg/ml時，可以抑制胰臟癌細胞及乳癌細胞生長達80%左右。另外，以DPPH法檢測藻藍素清除氧自由基的能力，在藻藍素78 μg/ml濃度時，經50 min後，清除率可達36%。因此，藻藍素不僅可以應用在醫學檢驗，更可以應用在促進免疫細胞增殖、抑制腫瘤細胞生長及清除自由基方面。由本論文實驗得知從海洋聚球藻所純化的藻藍素，具有活化多種生理機能，值得進一步研究，以期未來可被應用在保健及醫藥上。Phycocyanin, one of the major biliproteins from blue green algae, has various biological and pharmacological properties. It is a water-soluble and non-toxic fluorescent protein pigment. The present study used two-step column chromatographic method to isolate and purify c-phycocyanin from a marine Synechococcus. The isolation involved a multi-step treatments of the crude extract by fractional precipitation with ammonium sulfate, then by Q-sepharose column and finally ceramic hydroxyapatite column, giving a purity ration A620/A280 of 4.9. The yield of c-phycocyanin was 35% from Synechococcus dried powder. Respectively, further the purity and homogeneity were confirmed by native and SDS-PAGE electrophoresis. The estimated molecular weight of the phycocyanin was 128 kDa as determined by Sephadex S-200 gel filtration and electrophoresis.
Phycocyanin from the reported alga was assayed in vitro for proliferation stimulation in murine macrophages and for anti-tumor activity against human mammary and pancreas tumor cells, using MTT method. The results indicated that macrophage proliferation increased by 38% while treated with phycocyanin at the concentration of 65 μg/ml and the stimulation activity was a dose-dependent manner. Tumor cells used in the present study reduced markedly in growth rate in the presence of phycocyanin, i.e. reduced by 80% at concentration of 65 μg/ml. The obtained phycocyanin was also an antioxidant as determined by DPPH method. Its antioxidation activity, as expressed in % scavenge of oxygen radicals, reached 36% at concentration of 78 μg/ml. The above findings revealed that marine Synechococcus and the extracted phycocyanin can be a potent source for biomedical research, as well as therapeutic agent not only in immune stimulation and modulation, but also in tumor growth inhibition.中文摘要…………………………………………………….………………..1
Abstract……………………………………………………….………............2
壹、前言……………………………………………………….……….......... 3
一、微細藻類的保健用途……………………….…………….…….……3
二、藻藍素 (Phycocyanin) ………………………………….…………5
三、免疫調節活性研究…………………………………………………. 7
四、自由基……………………………………………………………......9
貳、材料與方法……………………………………………………………...13
一、實驗材料及設備…………………………………….………………13
二、實驗方法……………………………………………….……………16
叁、結果…………………………………………………………….……..….22
一、聚球藻細胞密度及吸收光譜……………………………..………....22
二、藻藍素的萃取及分離與純化……………………………………….22
三、藻藍素的分析………………………………………………..…..…..24
四、聚球藻免疫活性檢測…………………………………………....…..26
五、聚球藻的抗腫瘤活性……………………………………………......27
六、聚球藻的抗氧化活性…………………………………………….....28
肆、討論……………………………………………………………………...29
伍、參考文獻………………………………………………………….…..…3
Spatial analysis of Aging Population in Taiwan
No full text隨著社會經濟之變遷，台灣嬰幼兒死亡率降低、出生率下降、高齡人口死亡率減少、經濟富裕、醫藥發達，人民平均壽命逐漸延長，自1993年起65歲以上老人佔總人口比率達7.10%，正式步入高齡化社會。使得研究人口老化之學者如雨後春筍般地湧出，過去研究老化因素之學者曾藉由歷史脈絡、社會經濟因子等試圖找出人口老化之因素，但卻未考量地理空間之分佈對老化之影響。本研究結合地理學之空間概念以及人口學之靜態觀點與其他社經變數予以分析，並關注最小平方法後之殘差，其空間分佈是否為隨機分佈，有無產生空間相依性或空間異質性之問題。 本研究發現各年度年齡結構指數與社經人口變項之關係稍有不同，但與高中職人口比呈負相關、與性別比比呈負相關、與有偶且同居人口比呈負相關、與淨遷徙率呈正相關則同時存在於兩年度之資料中，表示高中職人口比、性別比或有偶且同居人口比越高，年齡結構則越老年化；而淨遷徙率越高，年齡結構則越年輕化。此外，光以傳統的最小平方法來分析空間資料略顯不足，受到空間相依性與空間異質性之影響，將會使得其估計結果有所偏誤、不具有效性。故對模型進行檢測，發現在空間相依性方面，以空間落遲模型優於最小平方法；而在空間異質性方面，則以地理加權平均優於最小平方法。Along with the development of social economy, mortality rate and birth rate reducing, economy wealthily, medicine is developed and the growth of life expectancy. Above 65 years old person divided by the total population reach 7.10% in 1993, officially marched into aging population society. So there were many scholars researched aging population, in the past studied scholar of aging population focused on population’s demographic history, the social economy factor and so on, attempted to discover the factor of the aging population. But actually they had not considered the distribution of the geography space. Therefore, this article gathers the geography and the static demography concept to analyze, and some factors of economy and society. And test the spatiall pattern of Ordinary Least Square’s residul, if it is random. If the answer is not, two broad classes of spatial effects may be distinguished, referred to as spatial dependence and spatial heterogeneity. This research discovery: the relationship of Age structure index and the variables of population and society have slightly difference in 1990 and 2000. But something are the same. The relationship of high education ratio, sex ratio and copule rate between age structure index are negative. And the realationship of net migration ration between age structure index is positive. Indicate that less high education ratio, sex ratio or copule rate and more net migration ration will increase Age structure. In addition, the residul having spatial pattern is not good to use Ordinary Least Square. Therefore carries on the examination to the model, discovered in the spatial dependence aspect, Spatial Lag model is better than Ordinary Least Square. Otherwise, in spatial heterogeneity aspect, Geographically Weighted Regression is better than Ordinary Least Square.目 錄 要 VBSTRACT VI一章 緒論 1一節 研究背景 1二節 研究目的 2二章 文獻回顧 4一節 台灣的人口轉型 4二節 人口老化之因素 6三節 人口老化之空間差異 11四節 空間計量模型 15五節 小結 19三章 研究問題與方法 20一節 研究問題 20二節 研究架構 20四節 研究設計 24五節 資料來源 25四章 研究成果 29一節 台灣之老化情況 29二節 空間相依性 30三節 空間異質性 44四節 研究限制 56五章 研究結論與建議 57一節 研究結論 57二節 研究建議 58考文獻 59錄1 PRESTON等(1989)人口老化拆解公式 64錄2 各變數面量圖 66 目 錄2-1 各式老化指標 73-1 變數定義 284-1 1990年齡結構指數迴歸分析 334-2 2000年齡結構指數迴歸分析 364-3 1990年之平均年齡迴歸分析 404-4 2000年之平均年齡迴歸分析 414-5 1990年之65歲以上人口比迴歸分析 424-6 2000年之65歲以上人口比迴歸分析 434-7 1990年齡結構指數之GWR模型 444-8 2000年齡結構指數之GWR模型 454-9 1990與2000年齡結構指數之異質性 464-10 1990年平均年齡之GWR模型 494-11 2000年平均年齡之GWR模型 494-12 1990年65歲以上人口比之GWR模型 504-13 2000年65歲以上人口比之GWR模型 514-14 1990與2000年平均年齡之異質性 514-15 1990與2000年65歲以上人口比之異質性 52 目 錄2-1 台灣的人口轉型 43-1 研究架構 224-1 1990與2000年之年齡結構指數 304-2 1990年OLS與SEM模型之殘差分佈圖 344-3 2000年OLS與SEM模型之殘差分佈圖 374-4 1990年齡結構指數模型之異質性 464-5 2000年齡結構指數模型之異質性 484-6 1990年之平均年齡模型之異質性 534-7 2000年之平均年齡模型之異質性 534-8 1990年之65歲以上人口比模型之異質性 544-9 2000年之65歲以上人口比模型之異質性 5
Physicians'adherence to guidelines for empirical treatment of urinary tract infection in Taiwan
No full textCost–benefit analysis of routine childhood vaccination against chickenpox in Taiwan: decision from different perspectives
No full text
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
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
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