Enamel prisms - rod-like bundles of hydroxyapatie crystals which are orientated at right angles to the tooth surface. Each prism can be traced from the outside of the enamel all the way to the dentine

发表于:2019-01-03 / 阅读(41) / 评论(0) 分类 医务英语

By Larry London Washington, D.C. 16 February 2007 watch RJA report Their name means nothing at all, but is instantly memorable. Their sound mixes heavy metal guitar with danceable beats of pop punk, and is instantly recognizable. Florida rockers Red

发表于:2019-01-12 / 阅读(101) / 评论(0) 分类 2007年VOA标准英语(二月)

On the final day of UN climate talks in Copenhagen, African leaders have renewed calls for a legally binding deal to fight climate change. Selah Hennessy | London 18 December 2009 Photo: AFP Sweden's PM Fredrik Reinfeldt (L), European Commission chie

发表于:2019-01-13 / 阅读(61) / 评论(0) 分类 VOA标准英语2009年(十二月)

HARBIN, March 2 (Xinhua) -- A therapeutic(治疗的) apparatus to treat Parkinson's disease has been developed in northeast China's Heilongjiang Province, according to the provincial science and technology department. It is a worldwide breakthrough i

发表于:2019-02-06 / 阅读(73) / 评论(0) 分类 英语新闻

ABIDJAN, Dec. 6 (Xinhua) -- Cote d'Ivoire's political crisis deepens with the appointment of two prime ministers by the two presidential candidates declared the winner of the Nov. 28 run-off respectively by the electoral commission and the Constituti

发表于:2019-02-08 / 阅读(66) / 评论(0) 分类 英语新闻

Properly analysed, Fraunhofer lines provide information about the exact chemical make-up of whatever is reflecting the light. 经过恰当分析,夫琅和费谱线可以提供关于任何反光物体的化学组成的确切信息。 Their patterns

发表于:2019-02-16 / 阅读(48) / 评论(0) 分类 经济学人科技系列