甲苯的所有化学方程式（通用2篇）
一个方程式解释了人类所有的问题 篇1
There's you， there's me and there's everyone else on the planet. How many of those people do you care about？
Good news！ If you’re like most Americans， you don’t have much reason to worry about the dangerous state of the world. Take Ebola. Do you have it？ No， you don’t， and neither does anyone in your family. As for Ukraine， it’s not your neighborhood， right？ Ditto ISIS.
Reasonable people might argue that a position like this lacks a certain， well， perspective， and reasonable people would be right. But that doesn’t mean it’s not a position way too many of us adopt all the same， even if we don’t admit it. If it’s not happening here， it’s not happening at all -- and we get to move on to other things.
I was put freshly in mind of this yesterday， after on the newest -- and arguably least honest -- argument being used by the dwindling community of climate deniers， and then posted the link to the piece on Twitter. Yes， yes， I know. If you can’t stand the tweet heat stay out of the Twitter kitchen. But all the same， I was surprised by one response：
“Just out of curiosity， how has ‘climate change’ personally affected you？ Has it brought you harm？”
And right there， in 140 characters or less， was the problem -- the all-politics-is-local， not-in-my-backyard， no-man-is-an-island-except-me heart of the matter. It is the sample group of one -- or， as scientists express it， n=1 -- the least statistically reliable， most flawed of all sample groups. The best thing you can call conclusions drawn from such a source is anecdotal. The worst is flat out selfish.
No， climate change has not yet affected me personally -- or at least not in a way that’s scientifically provable. Sure， I was in New York for Superstorm Sandy and endured the breakdown of services that followed. But was that a result of climate change？ Scientists aren’t sure. The run of above-normal， heat wave summers in the city are likelier linked to global warming， and those have been miserable. But my experience is not really the point， is it？
What about the island nations that are all-but certain to be under water in another few generations？ What about the endless droughts in the southwest and the disappearance of the Arctic ice cap and the dying plants and animals whose climates are changing faster than they can adapt -- which in turn disrupts economies all over the world？ What about the cluster of studies just published in the Bulletin of the American Meteorological Society firmly linking the 2013-2014 heat wave in Australia -- which saw temperatures hit 111?F （44?C） -- to climate change？
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Not one of those things has affected me personally. My cozy n=1 redoubt has not been touched. As for the n=millions？ Not on my watch， babe.
That kind of thinking is causing all kinds of problems. N=1 are the politicians acting against the public interest so they can please a febrile faction of their base and ensure themselves another term. N=1 is the parent refusing to vaccinate a child because， hey， no polio around here； it’s the open-carry zealots who shrug off Sandy Hook but would wake up fast if 20 babies in their own town were shot； it’s refusing to think about Social Security as long as your own check still clears， and as for the Millennials who come along later？ Well， you’ll be dead by then so who cares？
N=1 is a fundamental denial of the larger reality that n=humanity. That includes your children， and it includes a whole lot of other people’s children， too -- children who may be strangers to you but are the first reason those other parents get out of bed in the morning.
Human beings are innately selfish creatures； our very survival demands that we tend to our immediate needs before anyone else’s -- which is why you put on your own face mask first when the plane depressurizes. But the other reason you do that is so you can help other people. N=all of the passengers in all of the seats around yours -- and in case you haven’t noticed， we’re all flying in the same plane together.
甲苯的所有化学方程式 篇2
【关键词】 二甲苯酮；雄性生殖系统；精子质量
doi：10.3969/j.issn.1004-7484（s）.2013.11.065 文章編号：1004-7484（2013）-11-6191-01
二甲苯酮（BP-2）是一种常用的化工原料，广泛应用于化妆品和所料制品。研究表明BP2在体内能够被快速吸收，参与生物转化，但是血液中仍残留一部分，并且发挥生物学作用[1]。近年来国内外学者对BP-2对生殖系统发育及影响做了大量的研究，证实BP-2能够引起鱼类生殖系统功能的变化[2-3]，而BP-2对哺乳动物生殖系统的影响尚未广泛研究，本文拟通过对雄性小鼠灌胃服用BP-2，探讨其对生殖系统功能的影响。
1 资料与方法
1.1 主要试剂 BP-2和纯芝麻油购自Sigma公司，小鼠血清Testosterone、FSH、LH检测试剂盒购自BD公司，其他常用试剂和耗材本实验室提供。
1.2 动物分组与处理 3个月龄健康雄性C57BL/6J小鼠10只，体质量20-25g。实验室环境为光照时间08：00-20：00，室温控制在18-22℃，给予足够的食物和水。饲养2周后，将小鼠分为2组，每组5只。对照组：灌胃给予oil0.5ml（纯芝麻油）；BP-2组（二甲苯酮）：灌胃给予BP-2，250mg/kg（溶于0.5ml纯芝麻油中）。
1.3 取材 最后1次给完药物后，隔天取睾丸组织，称重；剪开附睾尾置于培养基中，让精子充分游出，计数精子数量并分析精子质量[4]；同时收集血液标本测定血清中激素水平。
1.4 统计学处理 采用SPSS10.0统计软件，计量资料以χ±s表示，组间比较独立样本t检验。
2 结 果
2.1 BP-2对雄性小鼠体重和睾丸重量的影响 BP-2处理小鼠7天后，体重降低，与对照组相比有统计学意义（P≤0.01）；此外睾丸重量也明显减少，与对照组相比有统计学意义（P≤0.01）。
2.2 BP-2对雄性小鼠血清激素水平的影响 与对照组相比较，BP-2处理后小鼠血清中睾酮和FSH水平降低，差异具有统计学意义（P≤0.01）；LH水平与对照组比较差异（P≤0.01）。
2.3 BP-2对小鼠精子质量的影响 与对照组相比较，BP-2处理小鼠7天后，精子密度和前向运动精子所占百分比降低，差异具有统计学意义（P≤0.01）；精子畸形率和精子DNA碎片率升高，差异具有统计学意义（P≤0.01）。
3 讨 论
在本实验中，我们采用中等剂量的BP-2作用于小鼠，结果发现其会引起小鼠体重和生殖器官重量的明显减少，这与雌激素或雌激素样物质作用不同种系大鼠为研究对象得出的结果相一致。睾丸重量的减少伴随着精子数量的减少，但是免疫组织化学结果显示，睾丸曲细精管和生精上皮组织并未发生明显改变（结果未显示），提示BP-2并未能影响睾丸组织的生精功能及产生精子的效率。目前已有一些关于雌激素雌激素样物质对精子活力和形态的研究，高雌激素水平会减少20%左右的前向运动精子[5]，同样在本实验中BP-2作用后，前向运动精子减少了将近30%，同时精子DNA碎片率显著增加，暗示BP-2会严重影响精子质量。此外，血清中睾酮含量减少，与雌激素的作用相近，有趣的是，睾酮的减少并未伴随着LH浓度的改变，包括LH受体的减少，间质细胞对LH的敏感性或睾酮合成相关酶敏感性的下降。
总之，本实验证实BP-2能够改变雄性成年小鼠的生殖系统内分泌的功能，并影响生殖器官的重量和精子的质量，关于其潜在的机制还需进一步的研究。
参考文献
[1] Christiane Schlecht，Holger Klammer，Holm Frauendorf，et al.Pharmacokinetics and metabolism of benzophenone 2 in the rat[J].Toxicology，2008，245：11-17.
[2] Fent K，Kunz P Y，Gomez E，et al.UV filters in the aquatic environment induce hormonal effects and affect fertility and reproduction in fish[J].Chimia，2008，62：368-375.
[3] Weisbrod C J，Kunz P Y，Zenker A K，et al.Effects of the UV filter benzophenone-2 on reproduction in fish[J].Toxicol Pharmacol，2007，225：255-266.
[4] 赵小莉，李芝兰，王进科，等.可乐对小鼠精子质量影响的研究，兰州大学学报（医学版）[J].2007，33（2）：10-13.