肉鸡腹水综合征的心电图学研究进展

近年对肉鸡腹水综合征的研究已取得进一步的认识 ,在研究肺动脉高压的同时更注意具有潜在作用的心脏病变的研究。家禽的心脏传导系统比较特殊 ,它含有一个返回分支束 ,使右房室瓣受传导神经的支配。当右房室瓣不受传导神经的支配时 ,瓣膜功能不全而引起右心室容量过大 ,可介导右心室肥大。心电图描记是研究肉鸡腹水综合征发病机理的有效手段之一。文章系统地阐述了肉鸡心脏的形态结构和传导系统的特点以及几种肉鸡腹水综合征试验模型的心电图学特征、肉鸡的心脏病理变化与心电图学特征之间的关系     

从腹泻金黄地鼠中分离出致病性大肠杆菌

从腹泻金黄地鼠中分离到 3株细菌 ,经染色镜检、生化反应鉴定和动物试验确证 :该菌为大肠杆菌。该试验为地鼠大肠杆菌的防制提供了流行病学资料与理论依据。     

甘蓝型油菜凸耳叶性状的观察

从油菜品种资源以及杂交后代中发现了油菜叶变异株－－凸变叶植株，套袋自交纯化后种植观察，发现油工有 凸耳叶性状最先起 始叶位多出现在第4－5片真叶上，在同一片真叶上一般可同时着生1－5个凸耳叶，凸耳叶面积大小一般在0.05-4.2cm^2。     

水霉属菌(Saprolegnia)分离培养技术研究

 对水霉(Saprolegnia)的分离培养技术进行了探索,筛选出大麻籽、油菜籽、红花籽、苍蝇、蚜虫、小麦粒、玉米片、茶叶、葵花仁9种材料作为诱发水霉菌的诱饵。其中油菜籽能防止腐霉菌(Pythium)污染,是初步纯化菌种、排除杂菌的适宜饵料。同时发现控制温度能使水霉在最短时间内分别产生无性或有性繁殖。在水培条件下,25℃左右适合菌丝及无性器官的发育,有性器官却不能产生,而只有在15~17℃条件下才能使水霉很快进入有性生殖阶段;在加入200mg/L链霉素的CMA培养基上促发有性阶段则需要在25℃左右的温度下进行,方能缩短培养时间。     

地被菊花粉萌发及花粉活力的研究

用ME的盐类和维生素附加16％聚乙二醇4000(PEG4000)和15％蔗糖对野菊及新红、塞旗红、玫瑰红的花粉进行培养。结果表明，萌发率分别为80．2％、85．3％、61．3％和46．5％。PE‰对菊花萌发有明显促进作用。但庶糖的作用不能被PEG所取代。菊花花粉萌发较合适的温度为10-20℃，在4-8℃时，萌发率及速度迅速降低，35℃萌发虽快。但花粉管短且破裂。在4℃条件下花粉可贮藏4-14d。但不宜干燥贮藏。     

原油管道改输天然气前的清管实践

为保证原油管道改输天然气后的输气质量和运行安全,必须在管道输气前实施清管。介绍了新疆塔河油田四、六区块4-1计转站至1号联合站原来的原油集输管道改输天然气前的清管方案和清管步骤,分析了其清管效果,指出利用经清管检测达标后的原油管道改输天然气与再建输气管道相比,不仅施工周期短,工艺操作简单,而且还可节约大量的建设资金。     

黄皮的生物学特性研究

通过本试验观察表明:黄皮[Clausena Lansium (Lour.)Skeels]的开花与温度有密切关系,温度高,开花过程短;温度低,开花过程长。花穗中的花轴增长速度也随温度升高而加快,花轴增长快,则花轴长,花穗大;反之,花轴增长速度慢,花轴短,花穗小。黄皮开花的顺序是从花穗基部第1—4个分枝开始,每个分枝则先从基部1—8个二次分枝首先开放。31℃是黄皮花粉萌发最适宜温度。在培养基中加入15—20％蔗糖或2.4—D,三十烷醇等生长调节物质,明显可提高黄皮花粉的萌发力。本试验对黄皮的物候期及植物学特性同时进行了研究。     

以球果量、雄花量等数量性状对油松优良无性系的再选择

本研究对油松无性系种子园 2 2个无性系的球果量和雄球花量进行观测调查 ,并对数据进行处理。通过无性系内和无性系间的方差分析、聚类分析和秩序排序法对各无性系进行分类和排序。研究结果表明 :无性系间球果量和雄球花量的差异极显著 ,而无性系内差异不显著。并筛选出 1 61 #,6#,2 9#,63 #,78#5个球果数量大 ,占总数的 46% ,雄花量高 ,占总数的 5 7.6%的无性系为优良无性系     

浅谈人造薄木生产中单板的漂白

详细阐述了木材颜色的成因及漂白机理，重点介绍了人造薄木生产过程中单板漂白工艺。研究表明，经漂白处理的单板，颜色明显变浅，色调也比较均匀，而且还消除了板面污染，对单板的染色十分有利。     

Alfalfa Phytoestrogen Content: Impact of Plant Maturity and Herbage Components

Legumes contain a range of non‐nutritional phytochemicals that may have health‐promoting effects in humans. In this study, we determined the concentrations of four phytoestrogens (coumestrol, apigenin, luteolin and quercetin) in field‐grown alfalfa (Medicago sativa L.). Differences between plants of different stages of maturity, between plant parts, and different canopy segments were assessed. The concentration of individual phytoestrogen in whole herbage varied between 15 and 225 μg g^?1 dry matter (DM) and was strongly affected by stage of maturity. Coumestrol and apigenin concentrations were highest at early vegetative stages, luteolin and quercetin at early vegetative and late flowering stages. All phytoestrogens were found in lowest concentrations at the early flowering stage (average 68 μg g^?1 DM); stage at which alfalfa is usually harvested when used as a forage source for animals. At vegetative stages, apigenin was the predominant phytoestrogen in herbage followed by coumestrol, the reverse being observed upon initiation of flowering; luteolin and quercetin were found at all stages in similarly lower concentrations. Concentrations of luteolin, quercetin and apigenin were 225, 410 and 690 % greater, respectively, in flowers than in leaves or stems; coumestrol concentration was similar between plant parts. In flowers and stems the predominant phytoestrogens were apigenin and quercetin, followed by coumestrol and luteolin. Similar concentrations (average 26 μg g^?1 DM) of each of the four phytoestrogens were found in leaves. Concentrations through the herbage canopy varied and were greatest at >60 cm from the soil surface for apigenin and coumestrol, but greatest at >60 and 0–20 cm for quercetin and at 0–20 cm for luteolin. The results suggest that if alfalfa is to be used as a source of phytoestrogens and is harvested for the production of herbal supplements or nutraceuticals, management will need to be adapted.