石杉碱甲类似物的研究Ⅲ．N－甲基吡啶酮石杉碱甲类似物的合成

石杉碱甲（１）是从中草药石杉属植物千层塔（ＬｙｃｏｐｏｄｉｕｍｓｅｒｒａｔｕｍＴｈｕｎｂ．）中分得的一种高效可逆的乙酰胆碱酯酶抑制剂，临床试验证实它对早老性痴呆症有显著疗效。本文报道Ｎ－甲基吡啶酮石杉碱甲类似物２和３的合成。２－甲氧基－５－甲氧羰基－１１－亚甲基－５，９－甲撑环辛－７－烯并吡啶（９）在乙腈中用三甲基氯硅烷和碘化钠选择性脱保护以定量的产率得吡啶酮１０，再用甲醇钠和碘甲烷甲基化得Ｎ－甲基吡啶酮１１，１１经碱性水解，Ｃｕｒｔｉｕｓ重排和氨基的脱保护得Ｎ－甲基吡啶酮石杉碱甲类似物２。通过类似的途径从中间体２－甲氧基－５－甲氧羰基－７－甲基－１１－酮－５，９－甲撑环辛－７－烯并吡啶（１４）合成了类似物３。类似物２和３的乙酰胆碱酯酶抑制活性均低于天然石杉碱甲。     

Mounting and calibration of stairs on piezoelectric force platforms

To calculate the centre of pressure using piezoelectric force plates mounted on pads, no net tensile stresses may be imposed on the surface of the plate. This condition is violated when stairs are attached to the plates, unless the plates are preloaded. Typical shear forces encountered when climbing stairs were used to determine required preloads of approximately 16.4 N/cm step height. Vertical and horizontal loads were applied at known locations on the steps, and points of application were calculated. Deviations were within ± 3 mm. The effect of point of application inaccuracy on calculated joint moments is considerable. A 2 cm medial shift in the point of application resulted in calculated peak knee abduction/adduction moment errors of 35%.     

A Utility Maximization Model for Evaluation of Health Care Programs

A linear health utility scale is described, complete with measurement instruments, that allows assignment of utility values to health states for any disease or treatment program. Given that the change produced by a health care program in the health states of a population is determinable, this utility scale permits assessment of the effectiveness of that program in terms of the change it produces in overall health utility. This is the basis of a model that will rank programs by their effectiveness/cost ratios or select them into a subset achieving the maximum effectiveness under specific cost or other constraints. Two algorithms are described, suitable respectively for priority ranking and for selection of programs giving maximum effectiveness under constraints, and the application of the model is discussed.