我国草地鼠害防治研究进展

严重的草原鼠害已成为引发草原退化、沙化、水土流失的重要因素,并威胁我国畜牧业的可持续发展、草原生物多样性保护、草原生态环境建设以及人们身体健康。防治鼠害常用的方法主要有化学防治、生物防治、不育剂应用及物理机械灭鼠。文章分析了各种防治方法的利弊,认为中草药植物源灭鼠剂在鼠害的综合治理上具有广阔的应用前景,应进一步研究并进行其产品的开发和研制。     

欢迎购阅下列新书

AIM: To investigate the contribution of angiotensin-converting enzyme inhibitor (ACEI) to the regulation of calpain system in infarcted myocardium. METHODS: Rat myocardial infarction (MI) model was established by permanent ligation of the left coronary artery. The treatment with the ACEI inhibitor rampril (1 mg·kg-1·d-1) was started 7 days prior to surgery. On day 1, 3, 7 and 14 after MI, protein levels of calpainⅠ, Ⅱ and calpastatin were determined in left ventricular free wall (LVFW), interventricular septum (IS) and right ventricule. RESULTS: CalpainⅠprotein level was increased in IS 14 d post MI, whereas the protein level of calpainⅡ was maximally increased in LVFW 3 d post MI. Rampril decreased protein up-regulation of calpainⅠ and Ⅱ, and reduced infarct size and interstitial fibrosis. Calpastatin protein expression was not affected by ACEI. CONCLUSIONS: CalpainⅠ is involved in cardiac remodelling in the late and calpainⅡ contributes to cardiac tissue damage in the early phase of MI. The heart protective effect of ACEI may be related to the inhibition of calpain system in the pathogenesis of myocardial infarction.     

灵芝多糖与三萜类的提取纯化工艺研究进展

多糖和三萜两大类活性物质是灵芝的主要药效成分.本文综述了从灵芝子实体、菌丝体和孢子中提取纯化灵芝多糖和三萜类物质的提取纯化工艺研究现状、研究趋势及研究内容.     

阿魏蘑、白灵菇及杏鲍菇亲缘关系的研究

利用PCR产物克隆测序测定了阿魏蘑、白灵菇与杏鲍菇rDNA内转录间隔区(ITS)的序列,并对所测序列进行分析.结果表明,阿魏蘑、白灵菇和杏鲍菇三者之间具有较近的亲缘关系,白灵菇与杏鲍菇具有非常近的亲缘关系,但阿魏蘑、白灵菇和杏鲍菇为3个不同的种.     

杨梅简易气调保鲜过程中气体成分变化及保鲜效果

以东魁杨梅为试材,研究简易自发气调贮藏(MA)和充氮气调贮藏(NA)条件下,杨梅贮藏小环境中气体成分的变化和对贮藏效果的影响。结果表明:在MA中,乙烯浓度在2d达到高峰;O2前4d浓度急剧下降,后维持在2.48%至1.78%;CO2一直呈上升趋势,试验过程浓度提高了124.3%。在NA中,乙烯高峰出现时间明显推迟、峰高降低;O2浓度维持在2.28%-1.82%,CO2变化与MA相似,浓度提高了131.3%。MA和NA均有效延缓杨梅鲜果的软化变质,减缓果实硬度和总糖的下降速率。贮藏至16d,NA和MA中果实变质率分别比对照下降31.6%和22.5%,硬度比对照增加25.93%和21.98%,总糖含量处理与对照无明显差异。     

浅谈蛋鸡开产体重对生产性能的影响

1、产蛋高峰短而低的问题。当养殖户遇到产蛋高峰不高或高峰上去后，又很快下降的问题时，往往将问题归咎到种鸡或饲料上，其实除了上面的问题外，还有一个重要的问题被忽视，这就是开产前的体重问题。根据国外各个品种的饲养要求，正常的鸡群在6周龄平均体重应达到标准上限或超标10％，均匀度达到90％以上；12周龄平均体重达标即可，均匀度应在85％以上；18周龄平均体重应达标或超标，均匀度达到80％以上。     

一种利用制冷机产生的副热生产热水的技术

为了保持牛奶的新鲜程度,防止牛奶变酸和细菌数升高,各个规模牛场和收奶站均配备了牛奶冷却设备,同时还需要通过锅炉或电加热等方式生产大量的热水来清洗设备。利用锅炉或电加热生产热水不但浪费了大量的财力、物力和人力,还造成了环境污染。现介绍一种不额外消耗能源解决热水供应的方法,供大家参考。1原理冷冻机在制冷的同时,产生大于制冷量的热量。压缩机高压出来的温度一般超过90℃以上,这部分热量一般经过风冷的方式通过散热器散发到室外。特别是夏天,气温较高,散热器散热效率较低,需要浪费大量的冷却水冷却,即使这样,有时温度还是降不…     

猪水泡病病毒结构蛋白基因的克隆及其蛋白二级结构和淋巴细胞表位的预测

以免疫信息学和反向疫苗学为理论根据，利用RT-PCR法获得了猪水泡病病毒（SVDV）HK／70株的基因组序列并测序，应用生物信息学相关软件和方法，对SVDV结构蛋白的二级结构的不同方面及其抗原特异性淋巴细胞表位进行了预测，综合评价了SVDV结构蛋白的抗原特异性细胞表位，并计算出一些潜在的抗原位点。结果表明，VP1蛋白含有的细胞优势抗原表位最多，但其他结构蛋白也含有抗原特异性淋巴细胞表位，有的甚至有可能成为优势抗原表位或对优势抗原表位有协同作用。     

Comparison of morphology, viability, and function between blood and milk neutrophils from peak lactating goats

The morphological features of blood and milk neutrophils from peak lactating goats were compared using light microscopy, scanning electron microscopy and flow cytometry in order to investigate the cytological changes of neutrophils after migration into the mammary gland. The kinetics of reactive oxygen intermediates (ROI) generation and gelatinase release of blood and milk neutrophils, with or without stimulation of phorbol 12-myristate, 13-acetate ester (PMA), were used to characterize their responses to inflammatory stimuli. Neutrophils isolated from goat milk were highly segmented and contained multi-lobed nuclei. Ultrastructurally, milk neutrophils were more ruffled on the surface compared to blood neutrophils. Approximately 30% of milk neutrophils were undergoing cell death, either necrosis or apoptosis, in contrast to 8% of blood neutrophils. The ROI production of activated milk neutrophils peaked earlier than blood neutrophils, but the duration and the intensity were much less. Neutrophils from both sources augmented the release of gelatinase in response to PMA (1 ng/mL). However, the amount of gelatinase released from milk neutrophils was lower (P < 0.05) than that of blood neutrophils. In summary, more neutrophils become apoptotic and necrotic in the mammary gland, presumably due to spontaneous aging, the process of diapedesis, and the interaction with milk components. Milk neutrophils have impaired functionalities in comparison with blood neutrophils. The information is relevant when studying mammary gland immunity and related diseases, such as mastitis.     

坡耕地暴雨结皮对作物生长发育影响的实验研究

采用盆栽和小区试验的方法,经3年试验发现,坡耕地土壤结皮对作物的出苗、生长、产量和生物量等均有不同程度的影响。小麦出苗率、苗高、最大苗高、产量和生物量分别降低了22.06％、4.60％、6.86％、1.16-9.84％和0.74-6.98％;结皮虽对玉米出苗影响不大,但延长了出苗期,使产量和生物量降低了5.66—9.17％和7.17—11.25％,而且随结皮厚度、强度和地表坡度的增加,其影响更为明显。因此,通过增加地面覆盖和雨后人工耕锄以消除结皮,增加产量和保持水土。