Comparison of chemistry analytes between 2 portable, commercially available analyzers and a conventional laboratory analyzer in reptiles

Background: Advantages of handheld and small bench‐top biochemical analyzers include requirements for smaller sample volume and practicality for use in the field or in practices, but little has been published on the performance of these instruments compared with standard reference methods in analysis of reptilian blood. Objective: The aim of this study was to compare reptilian blood biochemical values obtained using the Abaxis VetScan Classic bench‐top analyzer and a Heska i‐STAT handheld analyzer with values obtained using a Roche Hitachi 911 chemical analyzer. Methods: Reptiles, including 14 bearded dragons (Pogona vitticeps), 4 blue‐tongued skinks (Tiliqua gigas), 8 Burmese star tortoises (Geochelone platynota), 10 Indian star tortoises (Geochelone elegans), 5 red‐tailed boas (Boa constrictor), and 5 Northern pine snakes (Pituophis melanoleucus melanoleucus), were manually restrained, and a single blood sample was obtained and divided for analysis. Results for concentrations of albumin, bile acids, calcium, glucose, phosphates, potassium, sodium, total protein, and uric acid and activities of aspartate aminotransferase and creatine kinase obtained from the VetScan Classic and Hitachi 911 were compared. Results for concentrations of chloride, glucose, potassium, and sodium obtained from the i‐STAT and Hitachi 911 were compared. Results: Compared with results from the Hitachi 911, those from the VetScan Classic and i‐STAT had variable correlations, and constant or proportional bias was found for many analytes. Bile acid data could not be evaluated because results for 44 of 45 samples fell below the lower linearity limit of the VetScan Classic. Conclusions: Although the 2 portable instruments might provide measurements with clinical utility, there were significant differences compared with the reference analyzer, and development of analyzer‐specific reference intervals is recommended.     

基于GSM的鱼塘溶氧自动控制系统

鱼塘溶氧自动控制系统可根据测量到的鱼塘溶氧值实现增氧泵自动开启,从而获得较为稳定的鱼塘养殖环境,保证鱼类正常生长。系统采用STC12C5A16S2单片机控制,应用TC35i通讯模块实现远程信息手机接收与遥控操作。控制器具有溶氧控制值可设定、能测量溶氧及温度数值、自动启停增氧泵、异常温度短信提醒等功能。     

农业科技期刊论文中几组易混淆和用错的常用字词辩析

针对农业科技论文几组常用字词常出现混淆和用错的情况,笔者通过实例进行辨析,以供投稿作者和同行规范使用这些字词时作为参考。     

猪多能干细胞建系的培养条件及其分子调控网络研究

多能干细胞(pluripotent stem cells,PSCs)作为一类重要的细胞资源,成为目前国内外的研究热点,获得这类细胞在当今医学研究和生物技术的发展及应用中具有重要的意义。猪(Sus scrofa)由于其生理结构和代谢特征与人(Homo sapiens)较为相似,成为动物多能干细胞建系的重点研究对象。然而目前,猪多能干细胞建系工作仍存在很多难题。本文将从猪多能干细胞建系研究的进展和存在的问题入手,对照小鼠(Mus musculus)和人相关研究的成功经验,总结目前已经报道的猪多能干细胞的培养条件、调控因子、信号通路和基因表达特征,以期为建立猪胚胎干细胞和诱导多能干细胞系提供参考。     

关于肉种鸡代谢能的研究进展

本文主要就肉种鸡的代谢能水平及现状、能量限饲对肉种鸡的影响以及肉种鸡代谢能需要量的具体研究方法等几方面作一综述,为肉种鸡的营养研究提供参考。     

植物体内磷转运子的研究进展

近年来，人们对植物营养的遗传背景有了不断深入的了解，特别是磷营养。这一领域的研究工作开展得较早，而且随着分子生物学的快速发展已深入到分子水平，其中关于植物磷转运子的报道特别多。笔者对其结构、功能及表达调控方面的研究进展作一综述。     

Effect of FeEDDHA on the water relations of wheat

Water potentials, osmotic potentials and stomatal resistances were measured daily in a growth chamber during a two‐week period, in growing leaves of a drought‐sensitive and a drought‐resistant winter wheat (Triticum aestivum L. em. Thell.), which had the roots maintained in nutrient culture media with 0.001 or 0.01 M FeEDDHA. For both cultivars, the high level of FeEDDHA increased water potentials, turgor potentials, and stomatal resistances, and decreased osmotic potentials. Roots of plants grown with the high level of FeEDDHA had lower concentrations of Ca and K, and higher concentrations of Fe, than those grown with the low level. The results showed that the concentration of FeEDDHA used in plant‐water‐relation studies should be defined because the chelate affects the water balance of plants.     

不同物种和种植比例对小子虉草表型可塑性与竞争效应的影响

入侵植物小子虉草(Phalaris minor Retz.)为农田恶性杂草, 对其科学、有效的控制与管理是世界性难题。本文以小子虉草为试验对象,在温室条件下采用de Wit取代法,研究了其与小麦、蚕豆和油菜3种农作物在不同混种比例下, 小子虉草的表型可塑性与竞争效应, 以提高农田生态系统对该入侵物种的预警和控制能力。结果表明, 除混种比例对小子虉草的分枝数和主穗长度影响不显著外(P≥0.05), 作物种类、混种比例以及二者交互对小子虉草的株高、主穗种子数、剑叶面积和生物量有显著或极显著影响(P≤0.05或0.001)。在油菜混合种群中, 小子虉草的株高显著大于按同等比例与小麦、蚕豆的混合种群及其单一种群的株高, 但分枝数、主穗长、主穗种子数、剑叶面积和生物量则显著小于按同等比例与小麦、蚕豆混种时植株的上述指标。3种作物按不同比例与小子虉草混种时, 小麦、蚕豆和油菜的相对产量均小于1.0, 表明3种作物与小子虉草在田间以种间竞争为主; 小子虉草与蚕豆以各种比例混种、与小麦以1∶1和1∶2混种时, 其相对产量均大于1.0, 表明此时以其种内竞争为主; 油菜混合种群中小子虉草的相对产量均小于1.0, 表明此时以种间竞争为主。在混种比例大于1∶1时, 小子虉草与油菜的竞争平衡指数显著小于0, 表明此时油菜的竞争能力大于小子虉草, 而供试其他条件下小子虉草与供试作物的竞争平衡指数均显著大于0, 说明小子虉草对小麦、蚕豆及低密度种植条件下的油菜具有很强的竞争能力。本研究结果显示油菜对小子虉草具有较强的竞争抑制作用, 在油菜混合种群小子虉草的分枝数、主穗长、主穗种子数、剑叶面积和生物量显著降低, 因此在小子虉草入侵地大面积种植油菜有抑制小子虉草的效果。     

槐树与北京的历史文化

槐树在北京有着悠久的栽培历史,槐树和北京人民的生活联系密切;文章重点探讨了槐树文化的丰富内涵,及其对北京的民居、园林绿化、文学艺术等所产生的影响。       

因地制宜建设特色城市森林——以无锡市城市森林建设总体规划为例

以无锡市城市森林总体规划为例,探讨因地制宜的特色城市森林规划建设战略;以创建特色森林城市为目标,以无锡市自然、文化和城市发展3方面为重要内容,提出依水建林、森林生态建设、森林生态网络建设和森林生态文化景观区建设4大规划战略。