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Mithramycin A Inhibits DNA Methyltransferase and Metastasis Potential of Lung Cancer Cell
No full textSurvey of Substance Use among High School Students in Taipei: Web-based Questionnaire versus Paper-and-pencil Questionnaire
No full text目的：藉由一個隨機分派的試驗，評估網路版自填式問卷相對於紙筆版自填式問卷，是否可以幫助提升青少年對於物質使用及生活事件的陳報率。
方法：針對臺北縣市的國中、高中及高職的學生，進行分層暨二階段之隨機抽樣，並配合讓每個抽樣單位被抽取到的機率與單位大小成比例。在每個被抽選到的班級中，隨機將一半的學生分派回答紙筆版問卷(共990人)，另一半的學生回答網路版問卷(共928人)。由於每一位學生被抽樣的機率都不同，故在後續之盛行率估計和邏輯斯迴歸分析時，會以抽樣機率的倒數予以加權調整。
結果： 在容易取得的物質方面，喝酒的終生盛行率在網路版問卷中顯著比紙筆版問卷高，抽菸與嚼檳榔的終生盛行率在兩組中也有接近顯著的不同。在非法藥物方面，網路版問卷的安非他命終生盛行率顯著比紙筆版問卷高，K他命的終生盛行率在兩組中有接近顯著的不同。以多變項邏輯斯迴歸分析調整可能干擾因子後，兩組之喝酒與使用安非他命的終生盛行率仍具有顯著的不同。在各種生活事件的陳報上，網路版問卷組都比紙筆版問卷組高。此外，填寫網路版問卷的男性及國中、高職學生對於物質使用與生活事件的陳報率都比填寫紙筆版問卷的學生較高。
結論：網路版問卷相對於紙筆版問卷，可以提升青少年對於物質使用（包括容易取得的物質與非法藥物）和生活事件的陳報率。Objective: To evaluate whether a web-based self-administered questionnaire (web SAQ) can help to improve the reporting rate of substance use and stressful life events in adolescents as compared with the paper-and-pencil self-administered questionnaire (paper SAQ) via a randomized trial.
Methods: Students of the junior high, senior high, and vocational high schools in Taipei City and County were selected by a stratified, two-stage, probability proportional to size, random sampling. For each class selected, half of the students were randomly assigned to paper SAQ (n=990) and the other half to web SAQ (n=928). The inverse of the sampling probability for each individual was then used as sampling weight in the estimation of prevalence and logistic regression analysis.
Results: For readily available substance, the lifetime prevalence for the group of web SAQ was significantly higher in alcohol drinking and borderline higher in tobacco and betel nut use as compared with that for the group of paper SAQ. For illicit drug use, the lifetime prevalence for the group of web SAQ was significantly higher in use of amphetamine, and borderline higher in ketamine. In multiple logistic regression analysis, the difference between the two groups in alcohol drinking and amphetamine use remained significant. For each of four types of life events, respondents who were administered with web SAQ had significantly more reporting than those with paper SAQ. Boys and junior high, vocational high school students who were administered with web SAQ were more likely to report substance use and life events than those with paper SAQ.
Conclusions: Web SAQ leads to higher reporting rates of readily available substances, illicit drugs, and life events in adolescents as compared with those of paper SAQ.CONTENT
Abstract Ⅰ
Content Ⅲ
List of tables Ⅳ
Introduction 1
Methods 4
Participants 4
Measures 5
Statistical analyses 6
Results 8
Sample demographic features 8
Effects of administration mode 8
Mode effects among demographic subgroups 9
Discussion 11
References 15
Appendices 25
Ⅰ. Calculation of sampling weights 25
Ⅱ. Questionnaire 31
LIST OF TABLES
Table 1. Social and demographic characteristics of participants.. 19
Table 2. Demographic characteristics and educational courses among the adolescent students by using different methods of questioning.. 20
Table 3. Risk behaviors and life events among the adolescent students by using different methods of questioning 21
Table 4. Lifetime prevalence of substance use among the adolescent students by using different methods of questioning 22
Table 5. Lifetime prevalence of substance use among the adolescent students by using different methods of questioning and other covariates, such as gender and types of school. 23
Table 6. Lifetime prevalence of life events among the adolescent students by using different methods of questioning and other covariates, such as gender and types of school 2
Effect pf Carbon and Nitrogen on Development and Flowering of Oncidium Gower Ramsey
No full text瞭解碳素與氮素在植體內的分配對於植物的生長發育可提供許多資訊。文心蘭(Oncidium spp. )為臺灣第二大之蘭花產業，但在碳氮分配以及碳氮平衡這部份的資訊至今仍不完整。本研究之目的係為瞭解文心蘭Gower Ramsey在一完整生長週期內碳素與氮素之消長，並以碳素、氮素分配及碳氮平衡之觀點來探討文心蘭的生育與開花。
具開花能力之文心蘭Gower Ramsey在新芽發育前期，地上部比地下部之比值由5.4降至4.3，植株乾重與碳氮含量增加；由芽發育期進入假球莖出鞘期，植株經歷芽體分化與假球莖形成會消耗植體內之養分，而在假球莖成熟過程中再繼續累積。在花序萌發、抽長至分枝，植體內碳氮養分仍持續增加，隨著花序開放，假球莖、葉片及根部的乾重及碳氮含量皆會下降。在文心蘭生長週期內，假球莖與根部乾物質及碳氮含量之波動較葉片大。在新一世代發育時，當代假球莖持續累積碳素，對於氮素的積貯力相對較弱，植體內的氮素主要集中於葉片及根部。
分析植體生長量、碳氮之多寡與花序表現之相關性，可知植體乾重越高、碳氮含量越多，花序的長度越長、分枝數越多。具A級花序之植株植體內碳素濃度為46.3%，氮素濃度為1.6%；B、C和D及花序之植株碳素濃度介於43.7%-44.6%，氮素濃度則介於1.9%-2.4%。具不同商業切花等級之植株，當代假球莖內之非結構性碳水化合物濃度約為10.1%-13.8%；而在前代假球莖，切花等級越高，其非結構性碳水化合物之濃度就越高。
栽培於楊梅之文心蘭Gower Ramsey 在2009年6月至2010年5月間，植株抽梗率以8-10月最高，1-3月和6-7月最低，切花採收量以9-12月及5月份最高，花序品質則以5-6月最佳。隨著季節變化，環境光度與溫度改變，對於文心蘭之生長發育及碳氮的蓄積產生影響。6月與3月採收切花之文心蘭，當代假球莖所含碳氮養分較多，所採收之切花多為A級。9月採收切花之文心蘭，當代假球莖內的氮素濃度為1.4%，高於其他月份(0.7%-1.1%)，葉片生長旺盛，花序品質與3、6月相比略差，多為B級品。而12月採收切花之文心蘭，當代莖碳氮含量最少，根部生長量不佳，花序多為C級品。
分析具不同芽體數目之文心蘭植體內之碳氮含量，同時具有花芽及營養芽之植株，植體之乾重及碳氮養分高於只具營養芽之植株。具2-3個營養芽之植株，葉片乾重較低，乾重和碳氮養分分配於假球莖之比例大於只具單一營養芽之植株。
文心蘭之假球莖，對於植體內碳氮養分的平衡與分配具有調節之功能，當植體內碳氮養分不足或氮素較多時，假球莖對於養分之積貯力提高；而在器官分化和花朵開放等需要消耗養分生長階段，植株整體之碳氮比無顯著之變化，假球莖內的碳氮比會產生10-15左右的變動
Survey of Substance Use among High School Students in Taipei：Web-Based questionnaire versus paper-and-pencil questionnaire.
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