Darwin famously characterized the sudden appearance and rapid diversification of flowering plants (angiosperms) in the fossil record as an "Abominable Mystery".
A Chinese expat in Mexico, I was impressed with the efforts of the Mexican people coping with A/H1N1 flu, as well as China’s uncompromising preventive effort;
地膜覆盖栽培促进了大白菜生长发育，减轻了病虫害和冻害，可提高大白菜产量二成左右，并延长在田间贮存上市时间４０—５０天，能供应春节市场需要。每亩大白菜田还可节省用工１０个，降低成本２０％，增加
案例:米兰自己都不知道是怎么沾染上妇科病的,当她得知患上了细菌性阴道炎时,心情一下子就灰暗了。拿了药回家自我治疗,晚上老公大刘却没有分寸地过来索爱。米兰不肯,一来没
Plants flower in response to many varied cues, such as temperature, photoperiod, and age.The regulation of flowering time in annual Arabidopsis thaliana has bee
本文简要介绍了近十年来北京城市桥梁建设的发展。对北京城市桥梁建设中的几座典型桥梁作了扼要述评。对近年北京城市桥梁建设技术进展情况给出了一个简略摘要。最后,对于北
大连地区处于辽东半岛南端,气候比较温暖.以金州区为例,1984～1986年年平均气温在9.7～10.3℃之间,最冷的1月份平均气温在-5.9～-6.8℃之间,年极端最低气温-16.9℃。在这种气候条件
Histone lysine methylation plays an essential role in epigenetic regulation of gene expression in eukaryotes.While enzymes involved in the establishment of the
很多人都知道,不正确的坐姿会引起颈椎病、腰肌劳损等疾病。但有多少人知道,睡姿不正确对健康的损害呢?一般来说,睡眠通常有3种姿势,仰卧、侧卧和俯卧。而对女性来说,最好的睡姿是向右侧卧。 目前,俯卧睡觉的女性不多,因为这种姿势易使胸部受压,影响呼吸。对发育中的青少年女性而言,这一姿势还会影响胸廓和乳房发育,所以要尽量避免。 仰卧睡觉看似不影响身体各器官,其实在女性生殖系统的正常解剖中,子宫的位置