Rubber tree ( hevea brasiliensis ) is an important economic woody - crop in tropical areas . its latex is the unique source of crude rubber used in current industry . because of its special and important use , the rubber tree has been extensively planted in tropical areas . increase production is always the main target in rubber tree cultivation . since the ethrel was applied in increasing latex production in 1968 for the first time as a chemical stimulant , not only the latex production had been increased largely , but also a new set of rubber tapping system had been established , leading to a series of economic benefit . owing to ethrel " s extensive application , its side effects had been found more and more obviously , such as tapping dry , speeding up senescence , shortening the life span of rubber tree etc . in order to overcome the side effects and increase production more availably , for a long time , people had carried out lots of research work on cell level , membrane level , physiology and biochemistry of laticifer contents . but the mech anism why ethrel increased latex production was not yet understood completely . this study had cloned the ethylene receptor gene ( efrl ) from rubber tree , and researched the relationship between etrl expression in laticifers and ethrel stimulation on transcription level and protein translation level . the results were as follows : 1 但是，由于乙烯利应用的普及，乙烯利刺激割胶引起橡胶树发生死皮病及加速胶树衰老，缩短胶树寿命等副作用也越来越明显。为了克服这些副作用，使乙烯利能更有效地刺激增产，长期以来，人们在细胞水平、膜水平和乳管细胞内含物的生理生化层面上进行了大量的研究，但仍未完全了解乙烯对胶树的作用机制。本研究从分子水平入手，克隆橡胶树的乙烯受体基因( etr1 ) ，并在转录水平和蛋白质翻译水平上研究etr1基因在乳管细胞中的表达及与乙烯刺激的关系，取得了以下结果： 1
Based on the analysis mentioned above , a conceptual diagram explaining the physical process is put forward : stronger ( weaker ) convective activities in tropical areas stronger upward ( downward ) vertical anomaly stream in tropical areas more ( less ) moisture transports from " key regions " to shandong stronger ( weaker ) hadley and walker circulation stronger ( weaker ) east asian summer monsoon eap ( negative eap ) in 500hpa upward ( downward ) vertical anomaly stream rise in shandong subtropical high abnormally located northward ( southward ) more ( less ) rain in shandong province 弱季风年与山东夏旱年则相反。通过分析山东夏季降水与东亚夏季风以及大气环流异常的物理过程，得出了如下物理概念模型:热带印度洋以及南海-热带西太平洋地区对流加强(减弱)吟热带地区垂直上升(下沉)气流增强峥热带印度洋和南海一西太平洋地区水汽输送通量增加。
He said that ciguatera fish poisoning was not uncommon in tropical areas . it is mainly associated with the consumption of a big coral reef fish which has accumulated the toxin in its body , in particular internal organs , through eating small fish that consumes toxic algae in coral reef seas 发言人表示雪卡毒的食物中毒个案在热带地方并不罕见，这与进食大珊瑚鱼有关，因为这类鱼是吃在珊瑚礁海域生存的小鱼，而小鱼则吃有毒的海藻，于是毒素积聚在大珊瑚鱼身上，尤其是内脏。
A chp spokesman said ciguatera fish poisoning was not uncommon in tropical areas . it is mainly associated with the consumption of a big coral reef fish which has accumulated the toxin in its body , in particular internal organs , through eating small fish that consumes toxic algae in coral reef seas . the larger fish is therefore more likely to carry higher amounts of the toxin 生防护中心发言人说，雪卡毒的食物中毒个案在热带地方并不罕见，这与进食大珊瑚鱼有关，因为这类鱼是吃在珊瑚礁海域生存的小鱼，而小鱼则吃有毒的海藻，于是毒素积聚在大珊瑚鱼身上，尤其是内脏。
