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摘要： My dissertation investigates the unique ways organisms put effort (energy and nutrients) towards reproduction. My research asks how, delays might allow mammals to allocate limited resources to reproduction (i.e., are delays adaptive? ) and consisted of several components aimed at understanding the causes and consequences of reproductive delays in mammals. First, using the comparative method I examined ecological predictors and evolutionary origins of delays in the Order Carnivora in over 200 species using data published data of ecological variables. In this group I evaluated what attributes of an animal's ecology (i.e. where it lives, what it eats, how seasonal its habitat is etc.) are predictors of a species exhibiting delays. My results suggest that not only are animals that live in seasonal environments, and eat seasonality abundant foods most likely to evolve delays but also species that are larger. Second, I dissected museum specimens of male bats (N = 47 species) to assess if reproductive delays facilitate sperm competition. By reviewing the literature and inspecting museum specimens of bats with different types of delays and some without delays I was able to determine that delays might facilitate postcopulatory sexual selection (competition between the sperm from different males). Using these data I addressed the hypothesis that, once delays occur, they provide an avenue for postcopulatory sexual selection. I tested the prediction that males in species with delays between mating and egg-fertilization have larger testes than males of species that do not have delays before fertilization. Third, I empirically evaluated the costs and benefits of delays in a species that has pregnancies both with and without delays, Artibeus jamaicensis. Using this system I compared energy use, milk quality and food availability between the 2 pregnancies to evaluate the hypothesis that delays allow females to time the most expensive stage of reproduction, lactation, with periods o

关键词： prosthetic networks   artificial networks   transcriptional regulators   aptamer  

摘要： Synthetic biology has made significant leaps over the past decade, and it now enables rational and predictable reprogramming of cells to conduct complex physiological activities. The bases for cellular reprogramming are mainly genetic control components affecting gene expression. A huge variety of these modules, ranging from engineered fusion proteins regulating transcription to artificial RNA devices affecting translation, is available, and they often feature a highly modular scaffold. First endeavors to combine these modules have led to autoregulated expression systems and genetic cascades. Analogous to the rational engineering of electronic circuits, the existing repertoire of artificial regulatory elements has further enabled the ambitious reprogramming of cells to perform Boolean calculations or to mimic the oscillation of circadian clocks. Cells harboring synthetic gene circuits are not limited to cell culture, as they have been successfully implanted in animals to obtain tailor-made therapeutics that have made it possible to restore urea or glucose homeostasis as well as to offer an innovative approach to artificial insemination.

关键词： 麝   生物学特征   产业发展  

摘要： 我国麝类动物养殖业已有50余年的历史,但受到疾病和成活率的困扰,人工繁育种群长期徘徊不前。许多学者从饲养麝类动物的行为、生理、疾病等方面开展了研究,但未见结合麝类物种生物学特征与产业发展的研究。鉴于此,从麝类形态特征、行为特征、生理特征、遗传特征与养殖业的关系,分析目前麝养殖业发展需要关注的问题,并提出相应的见解,以期对我国麝类养殖业发展有所裨益。

关键词： Texas   Permian   Cretaceous  

摘要： Jacob Boll discovered the rich terrestrial fauna of the Texas Permian redbeds. Robert T. Hill mapped and named the Cretaceous formations of north Texas. Both, but especially Boll, supplied fossils to E.D. Cope. Of the more than 30 taxa named by Cope for fossils collected by Boll, Eryops megacephalus stands out as the species illustrated in the logo of the Society of Vertebrate Paleontology.

关键词： 农产品   分析   饲料   细菌纲   组分   培养基   定义   测定   测量规程   食品检验   食品   食品检测   食品料   调查方法   分析方法   微生物分析   微生物学   沙门氏菌属   抽样方法   试验   验证  

标准号: ISO/TS 6579-2-2012

摘要： ISO/TS 6579-2 gives a method for the enumeration of Salmonella spp. present in: products intended for human consumption and for the feeding of animals;environmental samples in the area of food production and food handling;animal faeces;and environmental samples from the primary production stage by calculation of the most probable number (MPN). The method is based on miniaturization of the dilution, pre-enrichment and selective enrichment steps. The selective enrichment medium, modified semi-solid Rappaport?Vassiliadis (MSRV), is intended for the detection of motile salmonellae and is not appropriate for the detection of non-motile salmonellae. It is possible that the method is less appropriate to enumerate Salmonella ser. Typhi and Salmonella ser. Paratyphi. The method is not appropriate for the enumeration of Salmonella spp. in (very) low contaminated samples (<1 cfu/g).

关键词： 多媒体技术   动物微生物学   应用  

摘要： 本研究将多媒体技术辅助教学引入到动物微生物学教学实践中,变革传统的动物微生物学课堂教学模式,探索其固有教学规律,提高课堂教学效果。

关键词： 饲料   链式反应   污染物   定义(术语)   测量规程   DNA   大肠杆菌   食品检验   食品   食品检测   在体外   调查   实验室   实验室设备   实验室测试   实验室试验   微生物食品   微生物分析   微生物学   微生物   最低要求   核酸   聚合酶链反应(PCR)   聚合酶   聚合酶链反应   规范(验收)   试验   验证  

标准号: ISO/TS 13136-2012

关键词： 癸二酸   丙二醇   熔融缩聚   注塑   生物相容性   细胞毒性试验   Ames试验   全身毒性试验   皮内反应   迟发型超敏反应   直肠黏膜刺激试验   植入试验   体外降解   人胆汁   模拟胃液   模拟肠液   体内降解   热灼伤   胆管损伤   内支架   大网膜  

摘要： 第一部分 聚癸二酸丙二醇聚酯的制备及吻合支架的制造 研究目的制备一种新型生物可降解高分子材料,并以此制造一系列空腔脏器吻合支架。 研究方法将癸二酸、1,3-丙二醇、1,2-丙二醇以2：3.75：1.25的摩尔比通过熔融缩聚二步法完成材料制备,经无水甲醇提纯。制备的材料采用凝胶渗透色谱(GPC)法测定其分子量,采用红外图谱表征合成产物。根据吻合支架设计模型铸造相应模具,然后通过注塑的方法制备相应的支架。 结果通过熔融缩聚的方法成功制备了目标产物聚癸二酸丙二醇聚酯(PSPP),重均分子量为67000左右,数均分子量为30000左右,分布宽度为2.2。红外谱图中分别在1161cm-1、1728cm-1、2927cm-1、2851cm-1出现吸收峰。以制备的PSPP材料通过注塑的方法制得各种空腔脏器吻合支架。 结论以癸二酸、1,3-丙二醇、1,2-丙二醇为单体,采用熔融缩聚法成功制备了PSPP。通过注塑法制造了一系列空腔脏器吻合支架。 第二部分 聚癸二酸丙二醇酯的生物相容性实验研究 研究目的通过体外和体内生物相容性实验,系统评价新型生物可降解聚酯材料PSPP的生物相容性,为进一步动物实验和临床研究提供实验依据。 研究方法依据我国颁布的医疗器械生物学评价指南(GB/T16886.2008),选择细胞毒性试验、Ames试验作为体外试验项目,全身毒性试验、皮内反应、迟发型超敏反应、植入试验和直肠黏膜刺激试验作为体内试验项目来对PSPP的生物相容性进行评估。 结果(1)体外试验：细胞毒性试验据24h、48h和72h观察,PSPP浸提液组的细胞相对增殖率RGR值均在75%以上,毒性判定均为1级；Ames试验在活化或非活化代谢条件下,PSPP组TA97、TA98、TA100和TA102的菌株回变菌落数均与阴性对照组相接近,无统计学差异(P>0.05)且PSPP组回复突变菌落数均未超过阴性对照组2倍,判断为阴性。(2)体内试验：皮内注射24h、48h、72h后观察每只动物在每一规定的观察时间内的原发性刺激记分均为0；全身毒性反应试验分别自尾静脉注射供试液和空白对照液4h、24h、48h和72h后,两组动物未出现死亡,进食正常,无呕吐、呆滞、运动机能减退、呼吸困难等症状出现；迟发型超敏反应试验PSPP加和不加弗氏完全佐剂情况下,在致敏后第3天和第7天及激发后24h和48h,皮肤过敏反应评分均为0分；直肠黏膜刺激试验连续直肠灌注1周后通过肉眼观察,结合组织病理学检查,未见直肠给药部位出现充血、红肿及坏死现象；植入试验大体标本观察,实验组和阴性对照组2w时可见周围组织轻度水肿,4w、12w均可见材料被一薄层囊壁包绕,与周围组织无明显粘连,未发现周围组织有充血、水肿、坏死等异常情况,组织学观察2w时两组炎症细胞反应均为IV级,囊腔反应均为IV级,4w时炎症细胞反应均为III级,囊腔反应均为II级,12w时炎症细胞反应均为I级,囊腔反应均为I级。 结论PSPP无论在体外和体内均表现出良好的生物相容性。 第三部分 聚癸二酸丙二醇酯的生物降解性能研究 研究目的研究聚癸二酸丙二醇酯(PSPP)在体外和动物体内不同介质中的降解规律,明确影响PSPP降解速度的主要因素,了解PSPP在消化道不同部位的降解时间。 研究方法体外降解选择人新鲜胆汁、模拟胃液和模拟肠液为降解介质,PSPP支架为样本,每种介质各设立48个样本。每个支架独立浸泡于装有10ml降解介质的平底试管内,37℃,100转／分钟持续振荡,每日更换浸提介质。每周每种介质分别取出3个样本用来观察外观和完整性,检测重量和重均分子量,扫描电镜下观察表面形态改变,观察期为4个月或至支架崩解。体内降解以巴马小型猪为实验对象,选择小肠、胃、结肠三个部位进行试验,样品5个为1串,分别悬挂在相应的消化道内。小肠每4天处死一头动物,共4头,胃和结肠每周处死1头,各6头。取出样本后分别观察形态变化,分子量变化,扫描电镜观察表面形态改变。 结果在体外人新鲜胆汁中,PSPP支架的降解周期约为3.5个月,观察期内总失重将近60%,重均分子量从原来的67000左右降低到31000左右,扫描电镜发现支架表面逐渐呈鱼鳞样改变伴脱落；在模拟胃液中,4个月内支架外形保持完整,支架的重量,重均分子量及支架表面形态改变均不明显；在模拟肠液中降解周期约为2.5个月,失重46%左右,重均分子量降至30000左右,扫描电镜下,材料表面呈鱼鳞样改变。体内降解中,空肠内的降解周期约为2周,重均分子量变化不明显,扫描电镜下材料表面明显被腐蚀；胃内降解6周支架厚度变化不明显,重均分子量稍有下降,扫描电镜下材料表面变得粗糙伴少量空洞；结肠

标准号: DIN ISO/TS 19036-2012

关键词： 动物学   教材  

ISBN: (纸本)9787122149541

摘要： 本教材由四篇30章组成，分别从微观和宏观层面上介绍了动物科学的基本知识和最新的研究进展。各篇间相对独立，每章后均附有思考题供读者借鉴。各学校可根据自己的需求，有选择地使用本教材。在动物多样性部分，选择了国际上最新的动物分类体系，以保持与国际接轨的特点。全书后附有较新的参考文献，供有兴趣的读者拓展阅读。