试析农产品健康与环境安全的几个问题

本文对影响农产品健康与环境安全的环境、农药、肥料、质量标准问题的当前状况进行了剖析,提出了一些新的疑点、难点和加以研究解决的途径。     

青海省"三江源"地区植被退化原因及其保护策略

对治多县32年的降水和气温变化资料的分析表明,自20世纪90年代以来,由于出现了较明显的增温减水现象,大气干旱加重,空气中相对湿度呈明显的波动减少趋势,因而造成了该地区的气候干旱化,不利于该地区草地生态系统生产力的提高和维持。同时,由于人口和家畜数量的增加,每个羊单位占有可利用草地从1953年的2．3hm^2降低到1994年的1．1hm^2,使牧压成倍增加。与60年代相比,平均产草量降低了50％以上,而有毒有害类杂草增加了20％～30％。到目前为止,约有1／3以上的草地处于不同程度的退化状态,约有1万hm^2的天然草地已经荒漠化或沙化,主要分布在水边、河岸附近、滩地、坡麓和居民点周围即冬季牧场,是局部的退化;但夏季牧场牧压较小,牧草利用率较低,因而保持相对良好状态。由此可见,草地退化的主要原因是超载过牧。但气候的干旱化给过牧对草地的影响起到了推波助澜的作用,其叠加效应加速了草地的退化沙化。同时,由于气候的干旱化可能导致高寒草甸面积的缩小,使高寒草原及荒漠草原的面积有扩大的趋势,从而导致该地区草地总生产力的下降。     

人工同龄纯林树冠面积比例系数计算及林分标准密度(立木株数)确定的研究

人工同龄纯林树冠面积比例系数计算及林分标准密度（立木株数）确定的研究熊奎山（甘肃省林业勘察设计研究院兰州７３００２０）关键词人工同龄纯林,树冠面积比例系数,林分标准密度确定Ｒｅｉｎｅｋｅ（１９８３）指出：具有完满立木度的同龄纯林,具有相同的单位面积株...     

2甲4氯标样的制备

本文论述了从商品２甲４氯钠盐水剂中制备２甲４氯标准样品的方法,采秀红外光谱,紫外光谱,高效液相色谱法鉴定其纯度。     

Ultrasonographic examination of the proximal tendon of the biceps brachii: Technique and reference images

Ultrasonography of the shoulder is of interest in the diagnosis of proximal forelimb lameness. The proximal tendon of the biceps brachii (PTBB) and its associated structures are frequently injured and should be included in the routine ultrasonographic examination of the shoulder. This paper describes a complete ultrasonographic procedure for examining the bicipital apparatus, on transverse and longitudinal scans, from the insertion of the PTBB on the supraglenoid tubercle to the muscle body below the intertubercular sulcus.     

丹顶鹤禽流感疫苗接种不良反应病例与治疗

扎龙保护区在2005年预防禽流感过程中,采用鸡禽H5N1亚型流感疫苗,对186只丹顶鹤做了H5N1的预防注射,注射剂量为成鹤2.0 ml,雏鹤1.5 ml.注射后7～8 d有4只丹顶鹤出现蔫食,精神不振以及神经症状等不良病理反应,经抢救治疗,均治愈.     

Clinical chemistry values and tissue enzyme activities in western barred bandicoots (Perameles bougainville)

BACKGROUND: The western barred bandicoot, Perameles bougainville, is an endangered Australian marsupial species whose survival is threatened by a papillomatosis and carcinomatosis syndrome. Investigations to characterize this syndrome would benefit from species-specific clinical chemistry data. OBJECTIVES: The purpose of this study was to determine plasma biochemical reference values and to determine enzyme activities in various tissues of P. bougainville. METHODS: Heparinized blood samples were collected by jugular venipuncture from 53 clinically healthy bandicoots of both sexes and at 3 geographic locations. Plasma was analyzed for routine clinical chemistry variables using an automated biochemistry analyzer. Tissues obtained following humane euthanasia of 3 bandicoots were analyzed for alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), creatine kinase (CK), alpha-amylase (AML), and gamma-glutamyltransferase (GGT) activities. RESULTS: Significant differences in the results were found for animals based on geographic location and sex; hence, results were expressed as minimum and maximum values. A population reference interval was calculated for AST activity (20-283 U/L). ALT was found mainly in the liver, with lower levels in cardiac and skeletal muscle and kidneys. AST was detectable in many tissues, including the heart, liver, kidneys, and central nervous system; CK was found in skeletal and cardiac muscle and central nervous system; AML was found in the pancreas; and GGT was found mainly in kidneys with lower levels in the intestines and pancreas. CONCLUSIONS: These findings will facilitate the interpretation of clinical chemistry results from P. bougainville and thereby inform population management and clinical decision-making.     

黄栀子丰产栽培与产业开发标准化项目示范技术

通过建立项目示范生产基地,总结出黄栀子的选地与整地、类型与品种选择、苗木繁育、造林技术、抚育管理、栀子采收与加工和黄栀子干果质量地方技术标准等7项技术。通过选择优良品种、因地制宜、科学集约经营和规范黄栀子生产的各项技术环节,制订出黄栀子丰产栽培与产业开发地方标准化技术,并推广应用于全市黄栀子的生产与产业开发,为国内外市场提供大量符合国家规定的黄栀子药材和符合绿色食品原料的黄栀子食用色素。     

《创花干燥机节能监测方法》行业标准简介

介绍了国家林业局新颁布的行业标准《刨花干燥机节能监测方法》，对标准中部分条款的制定作了具体的说明。     

认知参照点模型下的大学英语写作初探

认知参照点模型为视角探讨大学英语写作，是试图解释大学英语写作的认知过程，解读大学生英语写作的认知能力。以认知参照点为模型进行英语写作是学习者写作的一种基本认知能力。认知参照点的突显越强，英语写作的心智路径就越具有逻辑性。