书籍是否会被网络代替英语作文【一】
7月8号发表在《自然—医学》（Nature Medicine）的研究发现，当我们的皮肤细胞受到中波紫外线（UVB）的照射时，核糖核酸（RNA）的一种特殊形式“微小RNA”（micro RNA）即被损坏。被损坏的微小RNA随后会作为皮肤被晒伤的.信号释放出来，并激发邻近的健康细胞，引发炎症。整个过程的目的是为了移除被阳光损坏的细胞，因为这些细胞有可能会癌变。
美国加州大学圣地亚哥分校医学院的医学教授理查德.加洛（Richard Gallo）说道，我们的皮肤细胞可以检测到已的、受日光伤害的细胞，这些细胞会释放受损的RNA。其他因素也有可能在皮肤晒伤的过程中起到一定作用，不过研究结果认为，受损的RNA可以被看成是晒伤的分子标记。
研究结果对医疗情况有着一定的意义。比如，皮肤疾病牛皮癣的治疗方法之一就是接受紫外线照射。虽说紫外线能够减轻病症，但它也会提高皮肤癌的患病风险。而新发现显示，某些特定的RNA分子或许可以代替紫外线疗法，并且产生相同的益处。
此外，一些有特定类型自体免疫性问题的人即便只受到微量紫外线的照射，他们的皮肤也会在细胞开始损坏之前就产生灼烧感。对这些病人而言，阻塞微小RNA的通道可能会降低炎症。
然而，没有上述问题的健康人是不应该仅仅为了防止晒伤而去阻塞这个通道的，因为对身体来说，这是机体愈合和剥除受损细胞的一种重要的方式。加洛说道，炎症反应是人体自身对阳光酷晒的防护措施的一个正常部分。
书籍是否会被网络代替英语作文【二】
i think students should share some housework with their parents. the reasons are as follows. first, doing some housework can enable the students to have some sense of responsibility. there is a lot of housework in each family. as a member of the family, each one should do his or her share. since a student is a member of the family, undoubtedly, he is of no eception. in the second place, doing some housework can give the student opportunities to get to know his parents better. by doing housework, a student will know how hard it is for his parents to go to work everyday while raising a
family. he will make even greater efforts in his study later on. finally, doing some housework can give the student a chance to do some physicaleercises. since the student has to sit studying most of the time, this is certainly beneficial to his health.in light of the above, i strongly recommend that those who are not in the habit of doing housework start doing some right now. your parents will be pleased and you will learn something from it.
书籍是否会被网络代替英语作文【三】
nowadays, we can see some boys and girls who live in a small world of their own. they bury themselves among books and are proud of themselves. they think that it will make them lose their face if they do housework for they often think themselves very noble.
these young people are wrong. in my opinion every student should have a knowledge of housework. after all, they will have a family of their own, and they should do their part in keeping a good home. boys should also learn to do housework, for what will they do if they remain single? though not all boys remain single,yet they will be very helpful in the family if they know some housework. anyhow they will not lose anything, but, on the contrary, they will gain something useful.
for what i said above, we can find some eamples of our fellow-students studying abroad. all young men do housework as girls do. someone would argue that we can employ servants. this is true.however, what shall we do if the servant leaves us and all things are left to ourselves? we just cannot leave our clothes as they are and let worms and ants eat them up. and what can we do it we go and study in a foreign country where servants are out our means to employ? we must work for ourselves. why not start to learn to do housework now or else it will be too late? everyone should learn to do housework. what do you think about my idea, boys and girls?
