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）水平上的计算。比在３～２１Ｇ水平上的从头计算要精确得多。而计算时间只是它们的很少一部分。给出的电子密度断面图的分辨高出Ｘ射线实验图象的两个数量级。这种技术可以对大于目前能够处理的分子十倍的分子进行分析。Ｍｅｚｅｙ对７７３个原子的牛胰岛素和对超过１０００个原子的噬菌体蛋白以及对大于１５００个原子的ＨＩＶ蛋白酶（一种能复制病毒的致命酶即爱滋病病毒）进行了计算。附图为抗癌药物紫杉酚的计算结果。人们曾经试图用电子密度切片的方法来得到分子的形状，但因这种切片方法导致电子云之间存在间隙或重叠，看起来象分子键存在而失败。常用的量子化学计算方法受到计算量的限制只能画出大约１００个原子的分子电子密度图如维生素和较小的酞。由于分子大小与计算量呈４次方关系，即分子大小增加一倍，计算量增加１６倍。那么对于含有２０００个电子的蛋白质来说，少说也得进行２０００４计算，应用常用的计算方法，即使使用每秒运算百万次的超级计算机，需要１０００年才能完成。很多科学家认为清楚计算它的图象实际上是不可能的。用常用的量子化学计算方法来描绘ＨＩＶ这样大小的蛋白质电子云密度，约需３００年，而Ｍｅｚｅｙ用他的ＭＥＤＬＡ技术只用了３５分钟！该项技术的发展将?
) On the level of calculation. It is much more accurate than ab initio at the level of 3 ~ 21G. The calculation of time is only a very small part of them. The electron density profiles given are two orders of magnitude higher than the experimental X-ray images. This technique allows for the analysis of molecules ten times larger than currently available molecules. Mezey calculated bovine insulin of 773 atoms and phage proteins of more than 1000 atoms as well as HIV protease of greater than 1,500 atoms, a deadly enzyme that replicates the virus, the AIDS virus. The figure is the calculation result of anticancer drug paclitaxel. People used to try to get the shape of a molecule by electron density slicing, but because this slicing method led to gaps or overlaps between the electron clouds, it appeared as if the molecular bond was present and failed. Commonly used methods of quantum chemistry calculation subject to the limited amount of calculation can only draw about 100 atoms molecular electron density map such as vitamins and smaller phthalides. Due to the quadratic relationship between the molecular size and the calculated amount, that is, the molecular size is doubled, the computational amount is increased by 16 times. So for a protein that has 2000 electrons, it would take 20004 less to calculate it, and it would take 1,000 years to apply common calculations, even with millions of supercomputers per second. Many scientists think it is practically impossible to calculate its image clearly. It takes about 300 years to densify the electron cloud density of proteins of this size, using commonly used quantum chemistry calculations, while Mezey uses his MEDLA technology in just 35 minutes! The development of this technology will?