低溫SQUID應用於人體心臟磁場測量之研究

[[abstract]]摘要 此研究主要是量測人體的心磁圖(magnetocardiography，MCG)，使用的儀器是多通道心磁儀系統(multichannel SQUID magnetometer system)，在磁屏蔽屋(Magnetically-shielded room，MSR)的環境下，進行測量。 我們找180位心電圖 (electrocardiograms，ECG) 檢驗結果為心臟健康的自願者與100位心臟有疾病的患者，進行MCG量測。觀察正常人與患者之MCG，在不同的參數分析下所得的生理學參數之分佈情形。這些患者是要接受運動心電圖的檢測，檢查是否有心肌缺氧(ischemia)的症狀，而在這100位患者之中，運動心電圖正常( Positive )的有14位，異常(Negative)的有65位，無法判斷(Bolder line)的有11位；利用運動心電圖結果異常與正常的79位病人所得的心磁訊號資料，進行了十一種參數的分析，其中CMDyn(current moment dynamics) 、MAmax(map angle maximum)、MADyn(map angle dynamics)以及SIQTC有最明顯的差異性，此時所計算出的敏感性(Sensitivity)為、明確性(Specificity)皆有達到六成以上；同時也計算出靜態心電圖判讀後的敏感性為64.2 %及明確性為75.3 %，因此心磁圖分析在臨床檢驗上是具有價值的，是一個非侵入性、無輻射及其他傷害，測量的時間只需30秒，是一種快速而安全的前瞻性檢測方式。

Different Sensitivities of Selenastrum capricornutum and Toxic Strain Microcystis aeruginosa to Exudates from Two Potamogeton Species

The sensitivities of Selenastrum capricornutum and the toxic strain Microcystis aeruginosa to exudates from Potamogeton maackianus and P. malaianus were compared using exudation experiment, and the potential allelochemicals released by these two pondweeds into surrounding water were also analyzed. The growth of S. capricornutum and M. aeruginosa was inhibited by the exudates from the two macrophytes. Compared to the control, the cell densities of S. capricornutum decreased by 42.7% and 61.9% in 2.5 and 5 g.L(-1) FW P. maackianus treatments, and the cell densities of S. capricornutum also decreased by 65.8% and 73.5% in the two biomass density treatments of P. malaianus after three clays of treatments. After 3 days' incubation in 2.5 and 5 g FW.L(-1) P. maackianus exudates, the M. aeruginosa cell densities were higher in control than in treatment. As for P. malaianus treatments, the cell densities of M. aeruginosa were reduced by 16.5 and 65.8% of the control in 2.5 and 5 g.L(-1) FW marophytes at the end of incubation period, respectively. The allelochemicals exuded from the macophytes, which inhibited both S. capricornutum and M. aeruginosa, belonged to lipophilic and moderately lipophilic compounds according to the bioassay results of exudate fractionations. By multiple comparison statistics, the results showed that P. maackianus had stronger inhibitory effects on M. aeruginsa, while S. capricornutum was more sensitive to the allelochemicals of P. malaianus. The different sensitivities of the two algae were probably caused by three alcohol compounds (1-methoxy-2-methyl-2-Propanol, 2-methyl-2-Hexanol, and 4-ethyl-2,6-dimethyl-4-Heptanol) through the GC-MS analysis of the most active exudate fractions