【名词&注释】
胃肠功能(gastrointestinal function)、屠格涅夫(turgenev)、细胞分裂(cell division)、党的十五大(the 15 th congress of the party)、热带地区(tropical area)、领导人民(leading the people)、特色社会主义理论(characteristic socialism theory)、“基本路线”、党的十三大、党的十四大
[单选题]脾浊音区缩小，见于下列哪种疾病 （ ）
A. 左侧气胸
B. 肺气肿
C. 胃肠功能紊乱
D. 腹腔积气
E. 肠梗阻
根据以下内容，回答下面的题目。The death of a child, _51_ one’s own child,is something the mind can hardly comprehend．It seems togo _52_ nature．The end of a life that is still forming_53_ has just begun is an almost unthinkable cruelty．But it happens．Parents sometimes must witness the illness and death of the children_54_ whom they gave birth．And _55_ will ever fill theempty place that the dead child leaves behind．Parents_56_ to die before their children, which is the natural order of life events．When the situation is reversed and a child dies _57_ the parents itseems wrong．Yet we never know why one person dies andanother lives．But we do know _58_ a child is gone, theparents still have a future, as grey and worthless as it may at first seem．Death may take the child, but the love never _59_．The sorrow after a child’s death is one ofthe longest and hardest type of _60_ to live with．And ittakes long to deal with the parents’ own emotions．__________
根据下列短文，回答下面的题目。 A panel of government officials is worried．The air quality in some areas is not good．Theair is polluted with soot．The officials worry that the air is harmful to the people who breathethe air．The officials are expels．They study the environment．They diSCUSS ways to stop theair pollution．The panel decided to make，some changes to the law． The mew plan places strict limits on how much soot call be released into the air．Now，ameasurement of 65 parts of soot is considered safe．The new plan would reduce that number to30．The daily limit of pollution in the air would be cut in half． These new standards would affect industry．The limits would also affect people who ownwood stoves and fireplaces．The country will keep track of the air quality every day．Peoplewould be required to stop burning wood when the levels are high．They could also install a kindof special fireplace．These fireplaces burn very little wood．They do not pollute the air asmuch．Some countries will punish families who violate the ban．They will have to pay a fine fornot complying with the law． Some states do not have much industry．Their pollution problem is not too bad．Theywould stiU have to regulate how much pollution is released into the air．The experts hope thatthis ban will help keep the air cleaner．Before the plan becomes a law the public will have a chance to comment on it．Citizenswill have ninety days to ask questions and voice concerns about the plan．Then it will becomea law．The panel is made up of________．
根据以下内容回答下面的题目树木都是比较长寿的，自然界中常有许多百年以上的大树，甚至也有上千年的古树。一般比较准确地确定古树的年龄，多用“数年轮”的办法。 什么是年轮呢？就是木本植物茎干横断面上的同心轮纹，在树木茎干的韧皮部内侧有一圈细胞生长特别活跃，分裂也极快，能够形成新的木材和韧皮组织，被称为形成层。可以说树干的增粗全靠它的力量，这些细胞的生长情况在不同的生长季节中有明显的差异。春天到夏天的天气是最适于树木生长的，因此形成层的细胞分裂较快，生长迅速。所产生的细胞体积大，细胞壁薄，纤维较少，输送水分的导管数目多，称为春材或早材；到了秋天，由于形成层的细胞的活动逐渐减弱，产生的细胞当然也不会很大，而且细胞壁厚，纤维较多，导管数目较少，叫做秋材或晚材；当年的早材与晚材逐渐过渡，组成一轮，而晚材与次年的早材之间，界限分明，出现轮纹，根据树干基部的年轮，可以推测树木的年轮。 但是也有一些植物，如柑橘，年轮就不符合这种规律，我们叫它“假年轮”，因为它们每一年能够有节奏地生长三次，形成三轮。此外，在热带地区的树木，由于气候季节性的变化不明显，形成层所产生的细胞也就没有什么差异了，年轮往往不明显。 古树年轮的研究，对近年开展的古气候讨论以及空气污染情况的研究祁大有助益，首先树木的生长与气象的关系最为密切，从年轮宽，生长量大，推出那一时期风调雨顺，气温适宜；反之，年轮窄，则雨水稀少或干旱无雨，或气温过高或过低。美国科学工作者通过研究450株“世界爷”的年轮，发现它所记录的近百年气候变化，竟与现有文字记录相吻合；我国兰州大学在祁连山区采集900岁以上的圆柏树，发现其年轮宽窄变化与我国近1000年的气候变化相一致。此外，采用科学手段。可以从年轮里观察出空气污染的程度。美国人对二氧化碳及氧化物散落较多的军工厂附近的43株美国五针松及50棵鹅掌楸进行年轮分析，发现这些树木的历年生长量与该厂排放的污染物质的多少有密切关系，污染物多，树木生长量就少。 下列对树木年轮的解释，最准确的一项是
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