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关键词： please   Integration   details  

摘要： This special issue of Integrative Zoology is the third and final one in a series of issues containing papers presented at the Third International Conference on Rodent Biology and Management(ICRBM).The conference was held in Hanoi,Vietnam in August 2006 and focused on the areas of rodent biology,ecology and management(for details,please the summary report by *** see Integrative Zoology,1(4),194–195).The 1st ICRBM was held in Beijing,China,in *** 2nd ICRBM was held in Canberra,Australia,in *** of these two conferences were also published(Singleton et al.1999;Singleton et al.2003).This special issue contains a diverse range of papers examining rodents in urban environments,rodent behaviour and biology,and rodents in agricultural systems.

关键词： 实验动物资源   数据化   描述规范   技术规程  

摘要： 生物学特性数据化表达是实验动物标准化的内容之一,也是实验动物资源共享平台建设的重要组成部分和实现资源整合与共享的条件之一。制定实验动物资源描述规范和有关规程,对实验动物生物学特性和基本信息进行规范化和标准的整理和描述,可为科技工作者提供深入、详尽的资源信息,推动实验动物资源的建设与共享。

关键词： adaptation   embryo   predictability   reproduction   reptile   seasonal  

摘要： In the wet-dry tropics of northern Australia, temperatures are high and stable year-round but monsoonal rainfall is highly seasonal and variable both annually and spatially. Many features of reproduction in vertebrates of this region may be adaptations to dealing with this unpredictable variation in precipitation, notably by (i) using direct proximate (rainfall-affected) cues to synchronize the timing and extent of breeding with rainfall events, (ii) placing the eggs or offspring in conditions where they will be buffered from rainfall extremes, and (iii) evolving developmental plasticity such that the timing and trajectory of embryonic differentiation flexibly respond to local conditions. For example, organisms as diverse as snakes (Liasis fuscus, Acrochordus arafurae), crocodiles (Crocodylus porosus), birds (Anseranas semipalmata) and wallabies (Macropus agilis) show extreme annual variation in reproductive rates, linked to stochastic variation in wet season rainfall. The seasonal timing of initiation and cessation of breeding in snakes (Tropidonophis mairii) and rats (Rattus colletti) also varies among years, depending upon precipitation. An alternative adaptive route is to buffer the effects of rainfall variability on offspring by parental care (including viviparity) or by judicious selection of nest sites in oviparous taxa without parental care. A third type of adaptive response involves flexible embryonic responses (including embryonic diapause, facultative hatching and temperature-dependent sex determination) to incubation conditions, as seen in squamates, crocodilians and turtles. Such flexibility fine-tunes developmental rates and trajectories to conditions-especially, rainfall patterns-that are not predictable at the time of oviposition.

关键词： Animals   Blood Vessels   Cell Movement   Cell Proliferation   Cytochrome P-450 Enzyme System  

摘要： Epoxygenases, particularly of the CYP2C and CYP2J families, are important lipid-metabolizing enzymes. Epoxygenases are found throughout the cardiovascular system where their lipid products, particularly the epoxyeicosatrienoic acids (EETs), which are arachidonic acid metabolites, have the potential to regulate vascular tone, cellular proliferation, migration, inflammation and cardiac function. The receptors for EETs are, however, poorly understood. The peroxisome proliferator-activated receptors (PPARs) are a family of three (alpha, beta/delta and gamma) nuclear receptors that are activated by lipid metabolites. Activation of PPAR alpha and PPAR gamma, similar to the longer term effects of EETs, causes the inhibition of vascular cell proliferation, migration and inflammation. Interestingly, EETs and their metabolites have recently been found to active both PPAR alpha and PPAR gamma. The epoxygenase-EET-PPAR pathway may therefore represent a novel endogenous protective pathway by which short-lived lipid mediators control vascular cell activation.

关键词： 系统古生物学   生物地层学   笔石动物   辐射演化  

摘要： 弗洛阶是奥陶系第二个阶，其顶、底界线分别被定义为牙形石Baltoniodustriangularis和笔石Tetragraptus approximatus的首现层，层型剖面分别位于我国湖北省宜昌黄花场和瑞典西南部Hunneberg的Diabasbrottet采石场。弗洛期是均分笔石动物群辐射演化的重要时期，大量均分笔石类群在这一时期起源并迅速分异演化，成为该时期生物类群的主体，同时也是弗洛阶内部生物地层划分的主要依据。\n 目前，相对完整的弗洛阶笔石带序列已经在底界GSSP所在地区(斯堪的纳维亚)及北美(加拿大纽芬兰、美国)等地建立。但是，全球弗洛阶生物地层研究中普遍存在一个问题，即缺乏弗洛阶底界上下连续的含笔石地层，弗洛阶底界的位置不明确。作为弗洛阶底界GSSP的Diabasbrottet剖面，其弗洛阶地层发育不甚好，与下伏特马道克阶地层间可能存在间断，弗洛阶底界在剖面中的具体位置没有得到很好的控制。曾是候选GSSP的纽芬兰Cow Head半岛Ledge剖面也存在类似情况，其弗洛阶底界附近可能存在地层缺失。因此目前已建立的笔石带序列并不连续，很大程度上影响了弗洛阶笔石地层全球对比的精度。我国弗洛阶笔石生物地层研究工作开展较早，在扬子区和江南区都建立了相对完整的弗洛阶笔石带序列，但是这些笔石带序列是依据不同剖面资料所建，缺乏笔石分异度高、层位连续、完整的剖面作为支撑。此外，长期以来，我国在Tetragraptus approximatus带之下一直没有发现上特马道克阶最顶部的笔石带Hunnegraptus copiosus带，对弗洛阶底界(即宁国阶底界或阿伦尼格阶底界)的确切界定造成相当大的困难。\n 湖南益阳南坝剖面弗洛期笔石的分异度高、产出丰富、保存完好，而且笔石地层发育良好，与下伏特马道克期笔石地层连续，是进行弗洛阶笔石生物地层研究的理想剖面。为解决弗洛阶笔石带划分和对比中存在的问题，本文选择南坝剖面对弗洛阶的笔石古生物学及生物地层学进行了详细研究。通过三年的悉心研究，本文取得了如下重要进展：\n 1.发现并描述了弗洛期笔石13属28种，其中反称笔石类1属1种，均分笔石类12属27种，包含具有重要生物地层意义的笔石8属10种：Acrograptus gracilis、Baltograptus geometricus、Corymbograptus deflexus、Didymograptellus bifidus、Didymograptus demissus、Expansograptus constrictus、Pendeograptus fruticosus、Pendeograptus pendens、Tetragraptus akzharensis、Tetragraptus approximatus。这是对湖南弗洛阶笔石动物群的首次系统研究，同时也为华南(尤其是江南区)弗洛阶笔石古生物学研究提供了新材料。\n 2.在弗洛阶地层中，自下而上确立了4个笔石带，即Tetragraptus approximatus带、Pendeograptus fruticosus带、Didymograptellus bifidus带、Corymbograptus deflexus带。首次在湖南弗洛阶中建立了较为完整、可全球对比的笔石带序列。这是目前我国同期地层中首个层位连续的笔石带序列，可与GSSPs地区(斯堪的纳维亚、湖北宜昌黄花场)以及其他弗洛期笔石地层发育较好地区的笔石序列进行对比，大大提高了我国弗洛期与国际同期笔石生物地层对比的精度。\n 3.在弗洛阶底界之下识别出特马道克阶最项部关键的笔石带--Hunnegraptuscopiosus带。这一笔石带的识别，说明特马道克阶/弗洛阶界线附近的地层是连续的，弗洛阶底界被严格地控制在了Tetragraptus approximatus带底界。南坝剖面是目前已知可以确切界定弗洛阶底界的唯一剖面，它弥补了Diabasbrottet剖面的缺陷，具有成为弗洛阶底界GSSP辅助剖面的潜力。

关键词： 农产品   分析   饲料   化学分析和测试   菌落计数技术   定义   测定   含量测定   食品化学   食品检验   食品   试验研究   微生物分析   微生物学   微菌落计数   微生物   霉菌   基准方法   抽样方法   测试   酵母目  

标准号: ISO 21527-1-2008

摘要： This part of ISO 21527 specifies a horizontal method for the enumeration of viable yeasts and moulds inproducts intended for human consumption or feeding of animals that have a water activity greater than 0,95[eggs, meat, dairy products (except milk powder), fruits, vegetables, fresh pastes, etc], by means of thecolony count technique at 25 ℃ ±1 ℃ (References [1], [2]).This part of ISO 21527 does not allow the enumeration of mould spores. Neither the identification of fungalflora nor the examination of foods for mycotoxins lie within the scope of this part of ISO 21527 The methodspecified in this part of ISO21527 is not suitable for enumeration of heat resistant fungi, such asByssochlamys fulva or Byssochlamys nivea, in canned or bottled frud and vegetables

关键词： 主题词：动物学：生物学-实验-教学参考资料-动物学：生理学-实验-教学参考资料  

ISBN: (纸本)9787811067408

关键词： 乙酰胆碱酯酶   正电子发射电子断层扫描   放射合成   活体显像  

摘要： 第一部分　　 乙酰胆碱酯酶活性的PET显像剂-[11C]MP4A的制备　　 目的:合成能反映脑乙酰胆碱酯酶活性的PET显像剂[11C]4-乙酰氧基-N-甲基哌啶(11C]MP4A)的前体4-乙酰氧基哌啶(P4A);制备[11C]MP4A。方法:合成前体P4A。利用[11C]碘代甲烷合成模块合成的[11C]碘代甲烷([11C]CH3I)直接与P4A反应制备[11C]MP4A,或将[11C]CH3I通过三氟甲基磺酸银柱转化为[11C]-三氟甲基磺酸甲烷([11C]-Triflate-CH4)后再与P4A反应制备[11C]MP4A。结果:P4A化学纯度达99％以上。采用[11C]-Triflate-CH3制备的[11C]MP4A放化纯＞98％,轰击结束后(EOB)放射合成时间为20分钟,校正衰变后产率为40％-55％。　　 结论:采用[11C]-Triflate-CH3制备的[11C]MP4A放化纯度高,产率高。　　 第二部分　　 脑乙酰胆碱酯酶活性的PET显像剂-[11C]MP4A在大鼠体内分布的研究　　 目的:研究脑乙酰胆碱酯酶活性的正电子断层扫描(PET)诊断显像剂[11C]4-乙酰氧基-N-甲基哌啶([11C]MP4A)在大鼠体内的摄取和分布。方法:正常雌性SD大鼠按注射后5、15、25、35、45、60分钟时间点分组,尾静脉注射[11C]MP4A后断头处死动物,迅速取血,分离脏器和脑(大脑皮层、小脑和脑干),用自动γ放射性计数仪测定11C计数后称重。计算经衰变校正后不同时间点各脏器放射性摄取率,以％ID/g表示。结果:一次剂量的[11C]MP4A静脉注射后,血中的放射性活性在5分钟时％ID/g为13.44±1.88,清除迅速,60分钟时接近于基线水平。各脏器组织[11C]MP4A的摄取15-25分钟达到稳态。注射[11C]MP4A5分钟时大脑皮层放射性活性％ID/g为2.26±0.29。脑内各区域的摄取在注射后15-25分钟达到稳态。皮层的平均％ID/g大于小脑,两者比值范围为1.13-2.08。60分钟时小脑、脑干和皮层的％ID/g与其最高峰摄取的％ID/g相比分别下降了77％、8096和40％,皮层放射活清除最慢。结论:[11C]MP4A血中清除迅速。脑中各区域摄取在短时达到稳态,提示[11C]MP4A有较好的脂溶性透过血脑屏障。皮层摄取相对小脑高,清除慢,因此[11C]MP4A能更好反映皮层乙酰胆碱酯酶活性,适合作为脑乙酰胆碱酯酶活性的PET诊断显像剂。　　 第三部分　　 [11C]MP4A的临床前评估-PET活体显像转基因痴呆小鼠、老龄小鼠及猕猴的脑乙酰胆碱酯酶活性　　 目的:用脑乙酰胆碱酯酶活性的正电子断层扫描(PET)诊断显像剂[11C]4-乙酰氧基-N-甲基哌啶([11C]MP4A)对转基因痴呆小鼠、老龄小鼠及猕猴进行活体PET显像研究。方法:小鼠于尾静脉注射[11C]MP4A后,腹腔内麻醉小鼠;猕猴经一侧肘静脉麻醉后,于另侧肘静脉静脉注射[11C]MP4A。固定试验动物于扫描床,进行PET/CT扫描并采集图像。测量各感兴趣区域放射性浓度,计算各感兴趣区域放射总量占全身放射总量的百分比值,用％ID表示,比较两组小鼠间及猕猴的PET显像特点。扫描结束后将小鼠断头处死,分离脑(大脑、小脑和脑干),测定11C计数后称重。计算放射性摄取率,用％ID/g表示,比较两组小鼠脑放射性摄取分布特点。结果:PET扫描图像显示两组小鼠脑放射性聚集均对称分布,转基因痴呆鼠脑中放射性聚集较老龄鼠稀疏。转基因小鼠大脑放射性活性平均％ID/g值为1.49,老龄鼠大脑平均％ID/g值为2.62,p=0.025,两组差别有意义。猕猴[11C]MP4A显像脑内皮层下摄取最明显,对称分布,皮层也有中等度放射聚集,放射显像清晰。结论:[11C]肝4A在小鼠和正常猕猴脑放射显像图像清晰,对称分布浓聚于皮层下,与脑乙酰胆碱酯酶活性的组化分布一致。[11C]MP4APET可以活体显像脑乙酰胆碱酯酶的活性。

ISBN: (纸本)9787030200631