• 作者： 鄭葳; E. J. Ainsworth
• 作者服務機構： 私立東海大學生物系; 美國加州勞倫斯柏克萊國家實驗室
• 中文摘要： 本研究以光學及電子顯微鏡探討小鼠水晶體經單一劑量的X－射線及重粒子照射後四個月至三十個月的形態組織變化。四個月大的小鼠分別給予上半身或頭部照射，放射源為220 kVp X－射線及　Ar （570 MeV/amu）, Ar （500 MeV/amu）, Ne （470 MeV/amu），及 C （400 MeV/amu）重粒子射線。經0.05， 0.3，0.9 Gy Ne粒子照射後四個月，水晶體弓形部位之上皮細胞出現微細胞核。經過 0.3及0.9 Gy Ne照射後，前側纖維細胞質膨脹；後側纖維無顯著變化。經重粒子照射後十五個月之結果顯示同劑量的重粒子比X－射線照射更能引起組織之病變，如弓形部位之細胞排列不正常，前側與後側細胞不規則移動，纖維膨脹等。十五個月之結果亦顯示組織受損之程度與劑量，取樣時間及線能量轉移（LET）成正比。而自二十四個月的結果顯示當LET低於100 KeV/μm時，組織受損程度與LET值成正比。經過 Ar粒子照射後三十個月的水晶體，其組織含有不正常之細胞核，變異之纖維及雜質之出現，而不經照射的同齡對照組水晶體，則只有纖維膨大現象。
• 英文摘要： The morphology of the mouse lens was studied by light and electron microscopy between 4 and 30months after graded single doses of photons or charged particle exposure. Four-month-old mice were givenupper body or head only doses of 220 kVp x-rays or to Ar (570 MeV/amu), Ar (500 MeV/amu), Ne(470 MeV/amu) and C (400 MeV/amu) particles. The lenses examined in this pilot study were largelyfrom mice dedicated to other designed experiments; not all radiation conditions are represented at eachsample time. At 4 months after 0.05, 0.3 or 0.9 Gy Ne radiation, the micronuclei appeared in the epi-thelial cells at the bow region. The anterior fibers showed swollen cytoplasm containing amphorous materi-als after 0.3 or 0.9 Gy Ne exposure. The posterior fibers were relatively normal. The results at 15 monthsafter irradiation indicated heavy charged particles were more effective than x-rays for inducing morphologi-cal changes; however there were no qualitative differences in damage produced by heavy charged particlesand x-rays. Characteristic changes after irradiation included abnormal bow patterns, posterior and anteriormigration of nucleated cells in the cortex, swelling of fibers and the development of swirls of epithelium atthe anterior pole. The results also indicated that the degree of degenerative changes in lens fibers increaseswith increasing radiation dose and sampling time. The radiation-induced injury to lens fibers also showed arelationship to linear energy transfer (LET). The qualitative observations at 24 months indicated that lowenergy Ar (600 KeV/μm) is less effective than high energy Ar particles (100 KeV/μm) and radiation-induced injury in the lens fibers shows an LET-dependence when the ionizing density is less than 100 KeV/μm. At 30 months after heavy charged particle irradiation, the changes in control lens were the swollenfibers, while in the Ar-irradiated animals, aberrant fibers with abnormal nuclei, amorphous materials anddebris were observed.
• 中文關鍵字： lens; heavy ions; electron microscopy
• 英文關鍵字： --