苏皖南部丘陵茶园土壤的腐殖质组成及性质的研究

本文是对安徽祁门和十字铺、江苏宜兴和深水等地不同肥力水平的茶园土壤腐殖质含量、组成与性质的研究。土壤类型包括黄壤,红壤和黄棕壤。三个地区茶园土壤腐殖质组成都以富里酸为主,不同地区HA/FA值自黄壤向黄棕壤递增,同一地区高产茶园土壤HA/FA值大于低产茶园土壤,胡敏酸光密度值以黄壤最高,红壤居中,黄棕壤最低。     

棉酚和单宁含量与棉花对枯萎病抗性之间的关系

分析了枯萎病菌（Ｆｕｓａｒｉｕｍｏｘｙｓｐｏｒｕｍｆ．ｓｐ．ｖａｓｉｎｆｅｃｔｕｍ）侵染后棉苗体内棉酚和单宁含量的变化．结果表明：①抗病品种棉苗中棉酚和单宁含量高于感病品种，根茎中含量高于叶片；②氟乐灵播前土壤处理（２μｇｇ－１土）的棉苗，叶片和根茎部组织中的棉酚含量略高于未处理组，但单宁含量无明显差异；③枯萎病菌侵染后的棉苗叶片和根茎部组织中棉酚和单宁含量均有明显上升，抗病品种的棉酚量增加早、增幅大，而感病品种棉酚量仅在后期略有增加．但抗病与感病品种在单宁含量增加上无显著差异；④经氟乐灵处理后受枯萎病菌侵染的棉苗棉酚含量显著高于未经处理的发病棉苗，但单宁含量与未处理组无差异．由此认为，棉酚可能与棉花对枯萎病的抗病性有关，而单宁则与抗病性无关     

柿花象的生物学及防治研究

１９９１～１９９３年对陕西宁强县柿花象Ａｅｄｅｎｕｓｓｐ．的分布为害、生物学、发生与环境及防治方法进行了初步研究。结果表明，该虫主要分布于陕南、川北和陇东南的秦巴山区，一年发生Ⅰ代，以成虫在土壤里过冬，翌年４月中旬开始出蛰上树补充营养，５月中旬柿开花期成虫产卵花托皮下，６月上旬产卵幼果，幼虫蛀食为害引起落花落果。海拔８００ｍ处，弱树受害最重，树冠下部花受害重于树冠上部花。柿花初期喷布８０％敌敌畏或５０％对硫磷１０００～１５００倍液１～２次可控制危害。     

桃蛀果蛾寄主间生活史与杂交研究

在２５℃恒温、１４．５～１５．０ｈ光照条件下，比较了杏、苹果、枣、桃、酸枣、山楂、海红、石榴等８种寄主上桃蛀果蛾越冬幼虫出土和成虫羽化的时间差异，并进行了杂交试验。结果表明，幼虫出土和成虫羽化时期在寄主间差异明显；不同寄主来源的成虫间容易杂交，并产生可育的Ｆ＿１代。Ｆ＿１代滞育率差异悬殊，表明不同寄主上的桃蛀果蛾临界光周期有差异。     

英文广告中的修辞艺术

修辞可以增强语言的趣味性和生动性,在英文广告中具有不可低估的作用。英文广告中常用的修辞手法有:音韵(包括头韵和尾韵)、排比、夸张、双关、仿拟等。     

关于中国生猪产业的周期波动问题探析

随着中国养猪业向市场化迈进和产业结构及生产者行为的变迁,生猪周期逐渐显现出来。生猪市场的波动必然影响广大养殖企业和养猪户的生产积极性。本文利用历史数据对生猪市场的价格波动、生产波动及利润波动进行了实证分析,并对缓解生猪市场周期性波动提出了几点建议。     

MET amplification leads to gefitinib resistance in lung cancer by activating ERBB3 signaling

The epidermal growth factor receptor (EGFR) kinase inhibitors gefitinib and erlotinib are effective treatments for lung cancers with EGFR activating mutations, but these tumors invariably develop drug resistance. Here, we describe a gefitinib-sensitive lung cancer cell line that developed resistance to gefitinib as a result of focal amplification of the MET proto-oncogene. inhibition of MET signaling in these cells restored their sensitivity to gefitinib. MET amplification was detected in 4 of 18 (22%) lung cancer specimens that had developed resistance to gefitinib or erlotinib. We find that amplification of MET causes gefitinib resistance by driving ERBB3 (HER3)-dependent activation of PI3K, a pathway thought to be specific to EGFR/ERBB family receptors. Thus, we propose that MET amplification may promote drug resistance in other ERBB-driven cancers as well.     

铁岭地区稻瘟病近年发生动态分析

1993-2000年，在铁岭地区3个县区的生产田和试验田中的72个品种（系）上，采集了98份1000余个稻瘟病标样；采用单孢分离法分离应用有效单孢菌株52个；经中国7个鉴别品种上鉴定，52个单孢菌株划分为7群15个生理小种，填补了铁岭地区稻瘟病菌生理小种鉴定的空白。铁岭地区稻瘟病菌优势种群为ZD群，ZE群和ZF群；采用室内苗期和田间成株期结合的鉴定方式，鉴定铁岭地区水稻品种（系）35个；其中表现较为抗病的材料有：铁8711，开原7号，铁188，开9725，铁8958，开9909等。     

A SN2 reaction that avoids its deep potential energy minimum

Chemical dynamics trajectory simulations were used to study the atomic-level mechanisms of the OH- + CH3F --> CH3OH + F- SN2 nucleophilic substitution reaction. The reaction dynamics, from the [OH...CH3...F]- central barrier to the reaction products, are simulated by ab initio direct dynamics. The reaction's potential energy surface has a deep minimum in the product exit channel arising from the CH3OH...F- hydrogen-bonded complex. Statistical theories of unimolecular reaction rates assume that the reactive system becomes trapped in this minimum and forms an intermediate, with random redistribution of its vibrational energy, but the majority of the trajectories (90%) avoided this potential energy minimum and instead dissociated directly to products. This finding is discussed in terms of intramolecular vibrational energy redistribution (IVR) and the relation between IVR and molecular structure. The finding of this study may be applicable to other reactive systems where there is a hierarchy of time scales for intramolecular motions and thus inefficient IVR.     

武定鸡、茶花鸡肉用性能及肉质的研究

 测定武定鸡,茶花鸡不同年龄,不同性别的体态结构及肉的品质,进一步研究两品种肉用性能和各种氨基酸的含量。结果表明,由于种质特性不同,体态结构有差异,武定鸡为0.14～0.15,茶花鸡为0.16～0.19;屠宰率,全净膛率,胸、腿肌率,净肉率,两品种间同龄,同性对应相比均无显著差异。各品种内500日龄的净肉率极显著高于90日龄;肌肉中蛋白质,脂肪含量也是500日龄母鸡高于90日龄同品种的公母鸡,而含水量则下降。谷氨酸的含量,武定鸡的公母分别是18.23%,17.23%;茶花鸡的公母是17.43%,19.07%;已报道的太和鸡是18.31%,17.65%,三者极为近似.赖氨酸武定鸡胸、腿肌分别为9.33%,9.45%;茶花鸡为8.94%,9.41%;太和鸡为8.84%,9.08%;武定高于太和鸡和茶花鸡。