Comparison of two screen-film combinations in contact and magnification mammography: detectability of microcalcifications

A new dual-screen, dual-emulsion-film combination that allows a decrease in radiation dose of approximately 66% was compared with a widely used single-screen, single-emulsion-film system in contact and magnification mammography. Clustered microcalcifications randomly superimposed on a breast phantom were detected, and the location and number of individual calcifications were determined by four observers. The detectability of calcifications, determined with a receiver operating characteristic (ROC) analysis area, was 0.92 for magnification and 0.82 for contact mammography with the single-emulsion-film system, compared with 0.84 and 0.72, respectively, with the dual-emulsion-film system. More clusters were correctly located and more individual calcifications were counted with magnification than with contact mammography. The dual-emulsion-film system with the magnification technique performs as well as the single-emulsion-film system with the contact technique, while retaining a decrease in required dose of approximately 40%.     

New Delhi metallo-β-lactamase in Klebsiella pneumoniae and Escherichia coli, Canada

Multidrug-resistant Klebsiella pneumoniae and Escherichia coli isolates harboring New Delhi metallo-β-lactamase (NDM-1) were isolated from a patient who had returned to Canada from India. The NDM-1 gene was found on closely related incompatibility group A/C type plasmids. The occurrence of NDM-1 in North America is a major public health concern.     

高效液相色谱法对四种双氯灭痛软膏剂透皮效果的研究

目的：本实验采用高效液相色谱法,以离体小白鼠腹部皮肤为透皮屏障,比较了四种双氯灭痛软膏剂的透皮效果,方法：实验用法国Gilson公司的HPLC仪,以C18为固定相,甲醇－水（含HAc 0.36%)=80:20为流动相,紫外检测波长280nm。平均回收率为99．59％,RSD＜3．28％,检测限为1．0ug/ml。结果：1号样品透皮率最高,3号与1号相比较透皮吸收无显著性差异（P＞0．05）,2号或4号分别与1号相比,其透皮吸收均有显著性差异（P＜0．05）,结论：1号品值得进一步开发。