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When Lewis Ziska wanted to see how a warmer wood with more carbon dioxide in the air would affect certain plants, he didn’t set up his experiment in a greenhouse or boot up a computer model. He headed for Baltimore. Cities are typically 7 degrees warmer than the countryside, as well as big sources of CO2. So Ziska, a plant physiologist at the U.S. Department of Agriculture, compa,ed ragweed growing in vacant lots in Baltimore with ragweed in rural fields—and discovered the dark side of sunny claims that global warming will produce a "greening of planet Earth". Urban ragweed grows three to five times bigger than rural ragweed, starts spewing allergenic pollen weeks earlier each spring and produces 10 times more pollen. In as few as 20 years the whole world will have CO2 levels at least as high as some cities do now. As climate changes due to the greenhouse effect, hayfever sufferers would do well to lay in copious supplies of Kleenex. From mosquitoes that carry tropical diseases such as malaria, to plants that produce allergenic pollen, scientists are finding that a warmer, CO2-rich world will be very, very. good for plants, insects and microbes that make us sick. Although the most obvious threat to human health is more frequent and more intense heat weaves, such as the one that killed thousands of people in Europe in 2003, that is only the beginning. In the case of plants, it’s not just that they grow faster and shed pollen earlier as the woad warms. The carbon-enriched air also alters their physiology. In a six-year study at a pine forest managed by Duke University, where pipes and fans adjust the CO2 concentration and the air, scientists found that elevated CO2 increases the growth rate of poison ivy. More surprising, by increasing the air’s ration of carbon to nitrogen, elevated CO2 also increases the toxicity of urushiol, the rash-causing oil. "Poison ivy will become not just more abundant in the future," says Ziska. "It will also be more toxic. " Plants interpret warmth and abundant CO2as: what a great climate for reproduction. Monitoring stations in Europe are recording higher pollen counts for allergenic grasses and trees, led by birch and hazel, notes a 2005 study by the Center for Health and the Global Environment at Harvard Medical School. Those counts are rising earlier each year: the warming already underway is shifting the pollen season by almost one day per year. By 2017, you’ll be reaching for tissues nine days sooner than you do now. More good news: in a greenhouse world po]len will be not only more abundant but more allergenic, he and Ziska find. Since cities already have the high CO2 levels that the rest of the world can soon expect, "’there is no question these climate-related changes have already begun," says Arlington, Texas, Mayo," Dr. Robert Cluck. "Every summner we’re seeing West Nile virus earlier and earlier, and the higher levels of ozone that come with higher temperatures are increasing the rates of asthma and causing heart and lung damage comparable to living with a cigarette smoker. " In a greenhouse world, tropical diseases will expand their range and their prevalence. For instance, alternating floods and droughts—the pattern that comes with climate change—provide perfect conditions for mosquitoes that carry malaria, West Nile and dengue fever. Warming makes mosquitoes bit more. They’ll face fewer predators, too. The frequent droughts expected in a greenhouse world are murder on damselflies and dragonflies. As dengue fever, yellow fever and malaria extend their range to higher elevations and higher latitudes, those diseases could appear in the developed woad, too. The southern tier of western and eastern Europe, as well as the southern United States, are most at risk, says Harvard’s Epstein. Dengue fever has already popped up on the Mexican side of the U.S. border, a worrisome expansion of its current range. Say this for the climate contrarians who insist that a warmer world will he a better, more productive world: if they’re referring to allergens and pathogens, they’re dead right. What is the author’s main purpose in writing this article

A. To introduce the recent research on global wanning done by physiologists.
B. To explain how plants, insects and microbes make humans sick.
C. To warn people of the serious impact that the global warming will have on human health.
D. To discuss the relation between climate change and life on earth.

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患者,女,25岁,因停经50天感心慌,胸闷诊为“先天性心脏病合并早孕”来院咨询是否可继续妊娠。查体:口唇、甲床轻度发绀,血压正常,心率80次/分,律整,胸骨左缘第3~4肋间可闻Ⅰ~Ⅱ级收缩期杂音,肺动脉瓣第二心音亢进,双肺呼吸音清,超声诊断:室间隔缺损伴肺动脉高压,下列处理措施哪项是正确的

A. 等待至孕中期行引产术
B. 不宜继续妊娠,入院行人工流产术
C. 入院先行心脏手术,如心功能改善则继续妊娠
D. 在心内科和产科医生治疗下维持妊娠至足月
E. 严密监护心功能,出现心衰即刻终止妊娠

Three Main Literary Forms Ⅰ. Poetry Essential features: —form and music —evoking (1) —creating a(n) (2) —imagination —leading to new (3) , new feelings and experience Ⅱ. Fiction A. Short story —definition: a relatively brief (4) —subject matter: single incidents in daily life —essential features: (5) , unity and (6) B. Novel One important technique: (7) Three methods: —explicit presentation through (8) —presentation of character in (9) —presentation from within a character Ⅲ. Drama Origin: ancient Greek festival activities Structures of a play —exposition —rising action — (10) —falling action —ending New styles and forms

关于病毒性肝炎对妊娠的影响,哪项是错误的

A. 易发生DIC
B. 易发生产后出血
C. 早产发生与围产儿死亡率明显增高
D. 妊娠晚期患病,妊高征的发生率高
E. 孕早期患乙型肝炎,婴儿感染率25%

分析方法评价的效能指标为 用回收率表示

A. 耐用性
B. 定量限
C. 检测限
D. 精密度
E. 准确度

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