你铲过这样的草吗？

孔子东游，见田里放着农具，而农人不知去哪儿了，便拾起锄头围着一棵秧苗费力地铲起来。不一会儿，农人归来。一见大怒，愤愤地说：“你为什么铲我的秧苗？”孔子感到奇怪，便指着秧苗说：“你看，我铲的明明是草啊。”没想到农人更加恼火地说：“我种的就是喂马的草!”孔子不禁目瞪口呆。     

简析唐诗宋词中的“草”意象

中国古典诗词中多抒情,借景抒情,寓情于景,情景交融,诗人、词人往往会把情感心绪、意态与形象融合为一个表象,这便形成了特定的意象。而“草”意象是其中较为独特的一种,“草”这一意象在唐诗宋词中所表达出的隐喻义及其生成的渊源值得重视。     

一物降一物

青蒿,古代也叫"菣",是指一种香蒿。自古以来,中国各地中医使用不同的蒿草以"青蒿"入药。从1596年李时珍《本草纲目》首刻问世以来的近400年历史中,青蒿一直被尊为正品,稳居"太子"之位。其他均为赝品(假药)。在中医药历史中,现今大名鼎鼎的黄花蒿(又名臭蒿)连假药资格都没有,因为它     

中国古代市肆考略

古代中国市场分为草市、官市、军市、庙市。官市代表了古代市场发展的最高水平,它产生于西周,成熟于两汉,民国以后逐渐淡出。以北宋为界,中国古代市场的发展分为两个阶段,前一阶段由小到大,后一阶段由大变小。     

花盆底下的小草

我家的天台上种了许多美丽的花,有玫瑰、三角梅、绣球花……花盆里经常叁冒出一些不起眼的小草,最常见的是一种不知名的小草,叶子圆圆的,像一颗颗极小的青果子。隔三差五,妈妈总是毫不留情地把这些杂草连根拔起,抖一抖,随亏扔在花盆下,等它枯了,烧掉当肥料。     

地上有草

如果一块土地能很好地生长庄稼,那么它就一定能生长出一片丰茂的草来;如果一片土地不能很好地生长出庄稼,那么,它也可能会长出一片丰茂的草来。     

科学技术正改变着三大绿魔

众所周知的三大绿魔，是祸害西南部的紫茎泽兰、祸害东南部河道的水葫芦、祸害沿海滩涂的大米草。在一段时间内，三大绿魔疯狂肆虐，给我国的生态造成了巨大灾难，负责生态重建的科学家们正在不遗余力地努力对它们进行根治，尽管困难重重，但是科学家们的不懈努力，还是给人们带来了鼓舞和希望。     

Effects of osmotic stress on antioxidant enzymes activities in leaf discs of P<Subscript>SAG12</Subscript>-<Emphasis Type="Italic">IPT</Emphasis> modified gerbera

Leaf senescence is often caused by water deficit and the chimeric gene PSA612-1PT is an auto-regulated gene delaying leaf senescence. Using in vitro leaf discs culture system, the changes of contents of chlorophylls, carotenoids, soluble protein and thiobarbituric acid reactive substance （TBARS） and antioxidant enzymes activities were investigated during leaf senescence of PSA612-1PT modified gerbera induced by osmotic stress compared with the control plant （wild type）. Leaf discs were incubated in 20%, 40% （w/v） polyethylene glycol （PEG） 6 000 nutrient solution for 20 h under continuous light [ 130 μmol/（m^2·s）]. The results showed that the contents of chlorophylls, carotenoids and soluble protein were decreased by osmotic stress with the decrease being more pronounced at 40% PEG, but that, at the same PEG concentration the decrease in the transgenic plants was significantly lower than that in the control plant. The activities of superoxide dismutase （SOD）, catalases （CAT）, ascorbate peroxidase （APX）, guaiacol peroxidase （GPX） and dehydroascorbate reductase （DHAR） were stimulated by PEG treatment. However, the increases were higher in PSA612-IPT transgenic plants than in the control plants, particularly at 40% PEG treatment. Lipid peroxidation （TBARS content） was increased by PEG treatment with the increase being much lower in transgenic plant than in the control plant. It could be concluded that the increases in the activities ofantioxidant enzymes including SOD, CAT, APX, GPX and DHAR were responsible for the delay of leaf senescence induced by osmotic stress.