乳腺照片有效的摄影体位

目的:通过探讨有效的摄影体位,广泛开展乳腺普查,为临床提供高质量的乳腺照片,提高病人的生存率,降低死亡率。方法:对2547例年龄18岁～83岁的女性采用有效的摄影体位,内外斜位及头尾位进行乳腺照片检查。结果:普通乳腺片85%达到甲级片的要求,CR片95%达到甲级片的要求,整体上提高了影像诊断率。结论:通过采用有效的摄影体位,从整体上提高了乳腺疾病的影像诊断率,扩大了普查人群的范围。

Screening of a Test Charge in Plasma

Nonlinear screening of a test charge in plasma by electrons trapped or untrapped is studied. The obtained results are in rigorous estimations mathematically in comparison with the corresponding Debye screening forms.Meanwhile their validity is physically discussed and some confusions in literature are clarified.