Bacteria are extremely small living things. While we measure our own sizes in inches or centimeters, bacterial size is measured in microns. One micron is a thousandth of a millimeter: a pinhead is about a millimeter across. Rod-shaped bacteria are u

发表于:2018-11-28 / 阅读(424) / 评论(0) 分类 新概念优美背诵短文50篇

Bacteria are extremely small living things. While we measure our own sizes in inches or centimeters, bacterial size is measured in microns. One micron is a thousandth of a millimeter: a pinhead is abo

发表于:2018-12-01 / 阅读(141) / 评论(0) 分类 新东方背诵文选

Each of us harbors a unique collection of bacteria, on our outsides and our insides. Now, scientists are finding that the bacteria you get at birth may depend on how you got here. Because babies born vaginally have a different set of microbes than th

发表于:2018-12-24 / 阅读(39) / 评论(0) 分类 Scientific American(六)月

By Ruth Reader Washington, DC 13 February 2008 There is growing concern around the world over illnesses caused by new antibiotic-resistant bacteria, or so-called superbugs, and the decreasing effectiveness of antibiotics to treat infections. Earlier

发表于:2019-01-07 / 阅读(67) / 评论(0) 分类 VOA常速英语2008年(二月)

Experts: Let Produce Dry Out to Avoid Bacteria American researchers say farmers should wait one day after a rain storm or watering their fields to harvest fresh fruits and vegetables. They say gathering the crops at least 24 hours after rainfall incr

发表于:2019-01-12 / 阅读(112) / 评论(0) 分类 2015年VOA慢速英语(七)月

ROBERT SIEGEL, HOST: Now some good news, especially for babies around the world. Scientists in the U.S. and India have found an inexpensive treatment for a common infection. It could save hundreds of thousands of newborns each year. The treatment com

发表于:2019-01-16 / 阅读(46) / 评论(0) 分类 2017年NPR美国国家公共电台8月