欧盟国家现代农业的发展及其启示

本文通过对欧盟六国的现代农业发展情况的实地考察，总结了欧盟发展现代农业的五点经验，即注重调整传统农业生产结构，依靠科技进步，应用信息技术，搞好社会化服务，加强对农业的补贴和保护等，对我国发展现代农业具有启示和借鉴意义。     

Memory Accessing Mechanism of X86 Computer System In Protected Mode

Protecting mode is on importmant working method of X86_based computer system,which provides the hardware support for multi_task and multi_process operation system on X86 platform. During the low_level development of X86_based computer system,it is very important to understand the working method of memory that is a main part of computer system. This paper discusses the data structure and hardware component of X86_based computer system which support the two mechanism of accessing memory:segmenting and paging,as well as the process of converting logical address to linear address and mapping virtual address to physical address. Througn segmenting and paging mechanism,we can realize the independent address space for every process in multi_process system,as well as the measure for protecting the system memory which can prevent the system breakup caused by illegal memory access.     

实用早籼型两用核不育系选育策略与进展

简要回顾了我国水稻两用核不育系选育的三个阶段及取得的主要成绩 ,分析了存在的主要问题 ,提出了实用早籼型两用核不育系选育策略 ,并详细介绍了作者从事实用早籼型核不育系选育所取得的主要进展。     

Effects of TNFα and IL-10 on cytomegalovirus infection in human embryonic lung fibroblasts

AIM:To study effects of tumour necrosis factor alpha(TNFα) and interleukin-10(IL-10) on human cytomegalovirus AD169 (HCMV AD169) infection in human embryonic lung fibroblasts (HEL),and the ability of the infected HEL to produce TNFα. We have attempted to understand the effect of cytokines in the immune of HCMV infection. METHODS:TNFα、IL-10 were added separately with different concentrations before 24 h HCMV infection of HEL to study the effect of TNFα and IL-10 on multiplication of HCMV. HCMV was incubated with HEL, TNFα in culture supernatants were measured at 4, 24, 48, 72, 96 h postinfection. The level of TNFα was measured by enzyme-linked immunosorbent assay( ELISA). RESULTS:The addition of TNFα with the concentration of 10-100 μg/L or IL-10 with the concentration of 1-10 μg/L before 24 h HCMV infection of HEL could remarkably inhibited the multiplication of HCMV in HEL. Level of TNFα didn't increase in infected cell supernatants. CONCLUSION:TNFα and IL-10 play an important role in the immune of HCMV infection.     

毛中群光能利用率的研究

依据生态学原理,对毛竹林种群的含水率,热值,生物量等进行研究,结果表明,毛竹秆,枝,叶各组分的平均含水率分别为３９．９５％,３３．８１％和５０．８１％,热值依次为２０１００．２３、１９８９２．０３和１９４６０．６２,并在这基础上报毛竹林种群光能利用率,从而为毛竹林的经营与开发提供科学依据。     

耗氧率及溶氧胁迫对长蛸体内酶活力的影响

采用Winkler法测定水中溶氧含量,通过比较对照呼吸室与试验呼吸室水中溶解氧含量之差,测定长蛸(Octopus variabilis Sasaki)耗氧率及窒息点,并在不同程度的溶氧胁迫下测定长蛸体内多种酶的活力变化.结果表明,长蛸耗氧率在一个昼夜内呈现"低-高-低-高"的趋势;耗氧率与水温(10～30 ℃)呈正相关,与pH值(6.40～9.20)呈负相关;随着盐度的升高(14～31),长蛸耗氧率表现为两头高、中间平稳, 曲线呈凹状分布;雌性长蛸耗氧率高于雄性.窒息点随长蛸体重的增加而降低,平均体重为(30.50±6.03)g 的长蛸窒息点为0 4179mg/L;平均体重为 (54.50±4.65) g 的长蛸窒息点为0.3902 mg/L;平均体重为(97 00±11 36) g的长蛸窒息点为0.2738mg/L.随着溶氧胁迫程度的增加,LDH活力呈先升后降趋势,脂肪酶活力下降,SOD、POD、CAT、ACP、AKP和蛋白酶活力均呈"降-升-降"的趋势.     

谷物种子干燥机的现状和发展

谷物种子干燥作业是制种和安全贮种的重要环节。潮湿的种子在适当的环境下会产生霉变。种子发芽率降低。种子干燥方法有自然干燥和机械干燥两种。机械干燥具有生产率高、不受天气影响、确保种子发芽率等优点。已经越来越引起人们的重视。谷物种子干燥机必须具有低温干燥、精确控温、防止混种等基本要求，以确保有高的种子发芽率和种子的纯度。目前，谷物种子干燥机上广泛采用了微电脑全自动控制系统，开发研制了温室太阳能干燥装置、远红外谷物种子干燥机等新型干燥机械，使谷物种子的干燥作业向更为完善的方向发展。     

江淮地区低温冻害对不同类型小麦幼茎细胞结构的影响

为了解冻害对不同基因型稻茬小麦苗期幼茎细胞结构的影响,选用皖麦50(半冬性品种)、皖麦48(弱春性品种)和郑麦9023(春性品种)为材料,在低温条件下连续用显微镜观测幼茎分蘖节薄壁细胞质壁分离变化情况。结果表明,在低温天气发生的初期,三个品种只发生了轻微的质壁分离,回暖后可恢复。当0℃以下低温持续10d以上时,质壁分离现象加重,皖麦48和郑麦9023分蘖节薄壁细胞原生质体出现不规则收缩,导管和筛管破裂,细胞失水收缩率最高达到30%左右,明显高于皖麦50。不同品种细胞失水收缩最大值均出现在连续低温之后,与最低温度出现时间不一致。     

追氮时期对不同小麦品种光合特性和产量的影响

为了给小麦的优质高产栽培提供依据,以强筋小麦烟农19、中筋小麦皖麦52和弱筋小麦安农0305为材料,研究了追氮时期对小麦产量及光合特性的影响。结果表明,追氮时期对叶面积、叶绿素含量和光合速率影响显著,不同处理间均差异显著。另外,追氮时期对于小麦产量的影响显著,表现为拔节、孕穗期追氮比返青、起身期追氮更能提高小麦产量,其中拔节期追氮对小麦产量的提高尤为明显。