Box-Behnken设计优化黄精多糖酶法提取工艺     

杨德  薛淑静  黄蕾  郭鹏  高虹  史德芳  李露  陈晓春 《湖北农业科学》2017,56(16)

采用响应面法,以多糖提取率为评价指标,对酶解温度、酶添加量、酶解时间、料液比4个影响因素进行考察,优化酶法提取黄精多糖的提取工艺,另以Design-Expert 8.05软件对数据进行综合统计分析。结果表明,最优工艺为酶添加量3%、酶解温度54.8℃、酶解时间99 min、料液比1∶22.4(g/m L),经验证黄精多糖提取率为11.22%。利用Box-Behnken响应面法优选的黄精多糖酶法提取工艺稳定可行,可用于黄精多糖的提取。  相似文献   

七星瓢虫与异色瓢虫对烟蚜的捕食功能反应及寻找效应     

胡进锋  林伟  陈志厚  徐茜  林勇 《安徽农业科学》2017,45(28)

[目的]了解不同龄期七星瓢虫与异色瓢虫对烟蚜的控制作用。[方法]研究不同龄期七星瓢虫与异色瓢虫对烟蚜的捕食功能反应及寻找效应。[结果]2种瓢虫的日均实际捕食量随着蚜虫密度的增大而增大。从龄期看,在烟蚜密度相同时,七星瓢虫与异色瓢虫均为成虫对烟蚜的捕食量最大,其次依次为4龄幼虫、3龄幼虫、2龄幼虫、1龄幼虫。通过比较功能反应中的各参数可知,2种瓢虫对烟蚜的攻击率随着龄期的增加而提高,七星瓢虫对烟蚜的攻击率从1龄幼虫的0.562 0增加到成虫的1.174 1,异色瓢虫对烟蚜的攻击率从1龄幼虫的0.595 1增加到成虫的1.170 5;2种瓢虫相比,幼虫时期,七星瓢虫对烟蚜的攻击率小于异色瓢虫,而成虫则相反。七星瓢虫与异色瓢虫对烟蚜的寻找效应是随着猎物的增加而降低。[结论]试验结果为烟蚜的综合防治提供了理论依据。  相似文献   

Piloting an “Opt-Out” Option for Wildlife Surveys of the General Public     

Robert H. Holsman  Natalie Kaner  Jordan B. Petchenik 《Human Dimensions of Wildlife》2017,22(2):183-188

Random sample surveys may provide the best way to collect data that accurately represent public attitudes on wildlife issues, but survey response rates have declined in recent years. Often, little information is collected on why people choose not to participate. In a recent survey of public attitudes toward wolves in Wisconsin, we tested a method that allowed recipients to “opt-out” of participating, as well as indicate their reasons for doing so. Including this option increased our survey responses, and data showed significant differences in demographics between full survey respondents and opt-outs. The most frequently cited reasons for opting-out were lack of knowledge of the topic (63%) and trust in the state to manage wolves without their input (31%). Results suggest that providing a means for survey recipients to indicate why they are not participating can yield multiple benefits, although further testing of this method is needed.  相似文献   

Tolerability and pharmacokinetic profile of a novel benzene‐poly‐carboxylic acids complex with cis‐diammineplatinum (II) dichloride in dogs with malignant mammary tumours          下载免费PDF全文

V. M. Kristiansen  S. Dewi  T. E. Horsberg  T. J. Jonasdottir  L. Moe  B. Berlinger  S. Lindkær‐Jensen  S. Larsen 《Veterinary and comparative oncology》2017,15(1):118-132

The pharmacokinetic profile, tolerability and efficacy of benzene‐poly‐carboxylic acids complex with cis‐diammineplatinum (II) dichloride (BP‐C1) were studied in dogs with mammary cancer. A three‐level response surface pathway designed trial was performed on seven dogs. At each level BP‐C1 was administered subcutaneously daily for 7 days followed by a 7‐day rest period in a dose escalating manner. Adverse events according to VCOG‐CTCAE, performance status and tumour progression were recorded. The pharmacokinetic profile followed a two‐compartment model with rapid absorption, short distribution, and a slow elimination phase. The overall elimination half‐life was 125 h. The maximum tolerated dose of BP‐C1 was estimated to be above 0.46 mg kg^?1. A significant reduction in VCOG‐CTCAE toxicity which correlated negatively with increasing dose was found. The dogs' general performance status remained unchanged. No decrease in total tumour burden was found, although temporary tumour reduction was seen in some target tumours.  相似文献   

A pilot study evaluating the prognostic utility of platelet indices in dogs with septic peritonitis          下载免费PDF全文

Efa A. Llewellyn BVetMed  DACVECC  Jeffrey M. Todd DVM  DACVECC  Leslie C. Sharkey DVM  PhD  DACVP  Aaron Rendahl PhD 《Journal of Veterinary Emergency and Critical Care》2017,27(5):569-578

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响应面法优化高效液相色谱-柱前衍生化检测发酵乳制品中的组胺     

刘景  苏米亚  徐致远  刘振民 《乳业科学与技术》2017,40(6):24-28

采用高效液相色谱-柱前衍生化方法,对市售发酵乳制品(天然干酪、再制干酪和发酵乳等)中的组胺含量进行检测。对影响测定结果的衍生试剂(丹磺酰氯)用量、反应pH值、衍生反应时间和衍生反应温度4 个因素进行单因素试验和响应面优化多因素交互作用分析。结果表明:优化所得衍生化条件操作简便、高效、测定准确度和精密度均较高,能够满足精确测定乳制品中组胺含量的要求。  相似文献   

产肠毒素大肠杆菌K88诱导仔猪炎症反应的分子机制     

李海花  朱琪  王世琼  杨春蕾  赵向华  乔家运  王文杰 《中国畜牧兽医》2017,44(1):262-267

为探讨产肠毒素大肠杆菌（ETEC） K88感染仔猪发生炎症反应的分子机制,试验用ETEC K88灌服断奶仔猪,ELISA法检测攻毒后仔猪血清中白细胞介素8（IL-8）含量,实时荧光定量PCR方法检测淋巴结中Toll样受体2（TLR2）、Toll样受体4（TLR4）及其信号通路相关基因（髓样分化因子88（MyD88）、Toll相互作用蛋白（Tollip）、B细胞淋巴瘤因子3（Bcl3））的mRNA相对表达水平。结果发现,仔猪攻毒ETEC K88后6和24 h血清IL-8含量和淋巴结TLR2/4的表达水平均极显著或显著高于对照组（P<0.01;P<0.05）,且感染后24 h显著低于感染后6 h（P<0.05）;仔猪感染ETEC K88后24 h淋巴结中MyD88、Tollip和Bcl3的表达水平均极显著高于对照组（P<0.01）,但是感染后6 h时与对照组相比均无显著差异（P>0.05）。综上所述,ETEC K88感染仔猪可能是通过TLR2/4-MyD88信号通路产生炎症因子IL-8,促使仔猪出现炎症反应,且该炎症反应可能受Tollip和Bcl3蛋白的调控而被减弱。  相似文献   

Allogeneic major histocompatibility complex‐mismatched equine bone marrow‐derived mesenchymal stem cells are targeted for death by cytotoxic anti‐major histocompatibility complex antibodies          下载免费PDF全文

A.K. Berglund  L.V. Schnabel 《Equine veterinary journal》2017,49(4):539-544

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中国原木进口与木质林产品出口的动态分析     

苏蕾  刘意 《世界林业研究》2017,30(1):61-65

1992-2014年中国木质林产品出口总值增长37.7倍,年均增长率达到17.94%;而原木进口总值增长25.6倍,年均增长率为15.89%。原木进口与木质林产品出口存在相同的增长趋势。文中以原木进口总值和木质林产品出口总值数据为基础建立VECM模型,并通过正交化脉冲响应函数和方差分解分析证明,中国原木进口与林产品出口之间存在正相关关系,原木进口显著推动了中国木质林产品的出口,但原木的供应不足也将制约林产品出口规模的进一步扩大。因此,缓解原木供求矛盾和优化林产品出口结构成为推动林产品贸易健康发展亟待解决的问题。  相似文献   

不同砧木品种对核桃树体生长及光合特性的影响   总被引：1，自引：0，他引：1       下载免费PDF全文

李莉  周贝贝  徐慧敏  张俊佩  裴东 《林业科学研究》2017,30(3):472-478

[目的]采用将同一品种嫁接到不同砧木的方法,经过调查测试和分析,揭示杂交种‘中宁奇’的砧木特性,进而阐明砧木在经济林育种和栽培中的地位和作用。[方法]以砧穗组合上宋-14/中宁奇和上宋-14/宁优为试材,测定分析不同砧穗组合的生长量和光合特性指标。[结果]嫁接亲和性调查显示:2种砧木对同一核桃品种的嫁接亲和性均较高,但差异不显著。树体生长特性调查表明:上宋-14/中宁奇树高、干径、冠幅、新梢长度、新梢粗度、新梢着生小叶数及分枝力等指标显著或极显著高于上宋-14/宁优,‘中宁奇’作砧木可显著增强核桃树体的生长势。光合特性分析结果显示:2种砧穗组合间光响应曲线特征参数存在显著差异,上宋-14/中宁奇最大净光合速率(21.93μmol·m~(-2)·s~(-1))、光饱和点(1 550μmol·m~(-2)·s~(-1))及表观量子效率(0.062 mol·mol~(-1))分别比上宋-14/宁优提高17.90%、11.51%和16.98%,而光补偿点(16.53μmol·m~(-2)·s~(-1))则显著降低35.33%。[结论]核桃杂交种‘中宁奇’与‘上宋-14’核桃品种有较强的亲和性,以‘中宁奇’作砧木可显著提高树体的生长量和光合能力,使嫁接品种对光强的利用范围变广,从而提高树体对光环境的适应性。  相似文献