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1.
BPA(brooks parsimony analysis)是历史生物地理学研究的重要分析方法之一,在过去的20年内得以发展和完善。除了用于生物地理分布格局的支序分析并解释其形成原因外,BPA也可用于寄生物与宿主、物种与区系以及协同进化等方面的研究。本文详细介绍了BPA的原理以及初级BPA的分析方法。  相似文献   

2.
历史生物地理学中的BPA分析法Ⅰ:初级BPA   总被引:1,自引:1,他引:0  
BPA(brooks parsimony analysis)是历史生物地理学研究的重要分析方法之一 ,在过去的 2 0年内得以发展和完善。除了用于生物地理分布格局的支序分析并解释其形成原因外 ,BPA也可用于寄生物与宿主、物种与区系以及协同进化等方面的研究。本文详细介绍了BPA的原理以及初级BPA的分析方法。  相似文献   

3.
生物地理学的新认识及其方法在多样性保护中的应用   总被引:2,自引:0,他引:2  
近年来,众多分子证据和古生物学证据的出现促进了对生物地理学领域一些关键问题(如,扩散和隔离)的理解,并达成了较为统一的认识:1)扩散和隔离都是解释生物地理学格局的重要假说,并可能同时影响了生物的分布格局;2)历史生物地理学和生态生物地理学不是截然割裂的,两者结合起来有助于从不同层次上理解生物地理和生物多样性格局;3)不同的生物地理学研究方法应相互补充以揭示复杂的生物地理过程。学科思想的演变也使得生物地理学研究内容发生变化,本文还综述了当今生物地理学所关注的科学问题,并重点论述了生物地理学方法在生物多样性保护中的应用。  相似文献   

4.
对生物地理学的内涵、研究领域以及进展进行了简要介绍,认为近期海峡两岸生物地理学研究的目标应当集中在:末次冰期以来的海陆变迁对海峡两岸生物分布格局的影响、海峡两岸现代动植物区系的渊源、台湾最后与大陆保持陆地连接的时间与范围、东亚岛弧对台湾生物分布格局的影响以及海峡两岸生物的物种分化与生态适应性五个方面。同时认为海峡两岸现代生物分布格局关系的一种历史生物地理学解释,应当是一个在末次冰期期间存在于长江以南的大区系片断化后对海峡两岸各自不同环境适应的结果。  相似文献   

5.
鸟类分子系统地理学研究进展   总被引:1,自引:2,他引:1  
董路  张雁云 《生态学报》2011,31(14):4082-4093
分子系统地理学是当代生物地理学的重要分支,是以分子生物学方法重建种内和种上水平的系统发育关系,阐释进化历史,并通过分析近缘生物类群的系统发育关系与其空间和时间分布格局间的相关性构建生物区系历史的研究,是分子生物学与生物地理学结合的产物。中性进化学说和溯祖理论分析的建立,以及线粒体DNA和微卫星标记等分子遗传标记的应用,为分子系统地理学研究的开展提供了理论和实践基础。近年来,分子系统地理方法在鸟类学研究中的应用揭示了许多不同于传统认知的发现,为准确而深入的了解鸟类分子系统地理格局的差异和不同类群的起源中心提供了新颖的证据。目前的研究多从隔离分化说和扩散说的角度对鸟类分子系统地理格局的成因进行分析,而迁徙行为不同对鸟类系统地理格局的影响为成因的解释提供了新的角度。结合区域特点的比较分子系统地理研究,在更广泛的地域和更多类群中开展研究是我国鸟类分子系统地理研究的方向。此外,展望了第二代测序技术对分子生态生物地理研究具有的潜在促进作用。  相似文献   

6.
啮齿动物分子系统地理学研究进展   总被引:2,自引:1,他引:1  
系统地理学是研究种间及种内不同种群的形成、现有分布格局的历史原因和演化过程的一门学科。基于分子水平,能够更准确地界定物种分布格局,促进分子系统地理学的形成和发展。近年来,分子系统地理研究的开展,促进了对啮齿动物物种分布格局形成机制的理解。对啮齿动物的种内及种上分类阶元的系统演化关系、起源中心与演化历程、影响系统地理格局的因素、鼠害防控和保护生物学等分子系统地理学方面的研究进行了综述。并提出了啮齿动物分子系统地理学未来发展的四点展望:1)综合性系统地理学研究;2)区域系统地理学研究;3)物种演化的全面系统研究;4)新型分子标记和分析方法的发展。  相似文献   

7.
历史生物地理学进展   总被引:5,自引:0,他引:5  
生物地理学研究动植物的地理分布。历史生物地理学重建生物区系历史。分替理论的复兴动摇了散布理论的上百年统治。最近10年主要是分替理论推动了历史生物地理学,出现了多个途径——种系发生物地理学、分支分替生物地理学、特有性的俭吝分析和泛生物地理学。岛屿生物地理学理论有了改进和严格的实验检验;庇所学说产生了新的模型。最后就我国如何发展生物地理学提出了对策措施。  相似文献   

8.
历史生物地理学的进展   总被引:4,自引:0,他引:4  
近年来历史生物地理学的进展主要是隔离分化学派的进展。对隔离分化学派的几个分支学派,特别是分支生物地理学和泛生物地理学在理论和方法方面的进展作了简要回顾和介绍。最近十年来分子手段广泛应用于历史生物地理学研究的各个方面,尤其是谱系生物地理学的快速崛起是历史生物地理学的一个明显特征。对本学科的发展做了初步的展望。  相似文献   

9.
土壤微生物生物地理学研究进展   总被引:9,自引:8,他引:9  
贺纪正  葛源 《生态学报》2008,28(11):5571-5582
生物地理学是研究生物(包括种群、群落等不同层次)地理分布格局及成因的一门交叉学科。微生物生物地理学的研究长期滞后于宏生物地理学。鉴于土壤微生物在调控生物地球化学过程和维持生态系统功能方面的重要作用,对其空间分布格局及形成机制的认识具有十分重要的理论和实际意义。随着分子生物学技术的发展,对微生物多样性的认知日益深入。越来越多的证据表明,土壤微生物群落结构和多样性具有一定的时空分布格局,从而对微生物全球性随机分布的传统观点提出了挑战。对当前土壤微生物生物地理学研究中的一些概念性问题,如微生物物种的定义、微生物多样性的定量测度、对微生物全球性随机分布的争论等,进行了系统评述;以微生物种-面积关系和距离-衰减关系为例对当前最新的土壤微生物生物地理学研究成果进行总结,并初步探讨了土壤微生物群落的地带性分布问题;在传统生物地理学理论的指导下,提出了一个可用于验证土壤微生物空间分布格局形成和机制维持的简单研究框架。这些对今后土壤微生物生物地理学的研究有一定借鉴和指导意义。  相似文献   

10.
生物地理学的新进展   总被引:6,自引:0,他引:6  
近30年来,生物地理学的发展极为迅速。由于遗传学和生态学的介入,生物区系的研究由描述走向解释、分析。历史生物地理学中离散观点的兴起,不仅能对生物地理分布格局的形成过程作出客观的解释,也可对地球的演化提出生物学家的看法。  相似文献   

11.
Bisphenol A (BPA; 4,4′-isopropylidenediphenol) is an endocrine disruptor that is used as a material for the production of phenol resins, polyacrylates, polyesters, epoxy resins, and polycarbonate plastics. Endocrine-disruptive or toxic effects of BPA on living organisms through a number of cell signaling pathways have been reported. BPA induces carcinogenesis, reproductive toxicity, abnormal inflammatory or immune response, and developmental disorders of brain or nervous system through various cell signaling pathways. This review considers the literature concerning BPA and its association with cancer-related cell signaling pathways, reproductive toxicity-related cell signaling pathways, inflammatory or immune response-related cell signaling pathways, and brain and nervous system-related cell signaling pathways.  相似文献   

12.
Abstract. Burst-promoting activity (BPA) was measured in the sera from 31 children with aplastic anaemia (AA). BPA levels were elevated in most of the children with A A (65-2%), the mean value (137.7 ± 18.4%) being significantly higher than that in normal children (69.6 ± 9.4%), in children in the recovery period and in children with non-aplastic anaemia. There was a negative relationship between the BPA level in children with AA and the peripheral haemoglobin concentration. The BPA level was higher in those whose duration of illness was shorter than 1 year. In three cases of AA caused by chloramphenicol and benzene hexachloride and one case of congenital pure red cell AA, the BPA level was not elevated. Eleven patients received fetal liver cell suspensions intravenously (FLI). After FLI the BPA level in their sera was significantly reduced. According to these results, it appears that the elevation of BPA level is a special phenomenon of A A. The measurement of BPA in serum is helpful for differentiation between AA and other kinds of anaemia. The elevation of the BPA level in serum is a biological compensation for the haematopoietic disorder, and the measurement of BPA in the serum of patients with A A may be helpful in evaluating the haematopoietic condition.  相似文献   

13.
双酚A暴露对东亚三角涡虫急性毒性及神经酶的影响   总被引:1,自引:0,他引:1  
旨在探讨双酚A (BPA)对东亚三角涡虫的急性毒性及神经系统相关酶活性的影响。采用不同浓度的BPA处理涡虫24 h、48 h、72 h,求出半致死浓度,以此为基础,采用不同浓度的BPA处理涡虫24 h、72 h、144 h,测定AchE、ChAT及Na+~K+^-ATP酶活性。BPA对三角涡虫的24 h、48 h、72 h,LC50分别为12.18 mg/L、8.49 mg/L、6.43 mg/L。ChE、ChAT、Na+~K+^-ATP酶活性对BPA反应敏感,具有较好的规律性。24 h处理组,AChE酶活力随BPA浓度的升高而升高,72 h和144 h处理组则呈现先上升后下降的趋势,除0.643 mgBPA/L以外,其它处理组均表现出了时间-效应关系;在BPA胁迫下,ChAT酶活力均呈现降低趋势,在BPA浓度为0.643 mg/L、1.286 mg/L时,表现出了时间-效应关系;24 h、72 h处理组Na+~K+^-ATP酶活力随BPA浓度升高呈现先上升后下降的趋势,144 h处理组则呈现下降趋势,Na+~K+^-ATP酶活力随BPA胁迫时间的延长呈现先升高后下降的趋势。BPA对涡虫具有较强的生态毒性,AchE、ChAT、Na+~K+^-ATP酶活性可与其他敏感指标一起作为水体BPA污染的早期监测指标。  相似文献   

14.
Bisphenol A (BPA) is an organic compound to which human populations are ubiquitously exposed. Epidemiological data suggest BPA exposure might be associated with higher rates of diabetes and reproductive anomalies. Health concerns also include transgenerational consequences, but these mechanisms are crudely defined. Similarly, little is known about synergistic interactions between BPA and other substances. Here we show that acute and chronic exposure to BPA causes genome-wide modulation of several functionally coherent genetic pathways in the fruit fly Drosophila melanogaster. In particular, BPA exposure causes massive downregulation of testis-specific genes and upregulation of ribosome-associated genes widely expressed across tissues. In addition, it causes the modulation of transposable elements that are specific to the ribosomal DNA loci, suggesting that nucleolar stress might contribute to BPA toxicity. The upregulation of ribosome-associated genes and the impairment of testis-specific gene expression are significantly enhanced upon BPA exposure with a high-sugar diet. Our results suggest that BPA and dietary sugar might functionally interact, with consequences to regulatory programs in both reproductive and somatic tissues.  相似文献   

15.
The objective of the present work was to analyze the interrelationship between the aerobic degradation of BPA and readily biodegradable substrates by activated sludge (AS) in semi-continuous reactors (SCRs). AS were obtained from three SCRs fed with glucose, acetate or peptone. AS from these reactors were used as inocula for three SCRs that were fed with each biogenic substrate, and for three SCRs that were fed with the biogenic substrate and BPA. In all cases, dissolved organic carbon (DOC), BPA, total suspended solids (TSS) and respirometric measurements were performed. Although BPA could be removed in the presence of all the tested substrates, AS grown on acetate exhibited the longest acclimation to BPA. Reactors fed with peptone attained the lowest TSS concentration; however, these AS had the highest specific BPA degradation rate. Specific DOC removal rates and respirometric measurements demonstrated that the presence of BPA had a negligible effect on the removal of the tested substrates. A mathematical model was developed to represent the evolution of TSS and DOC in the SCRs as a function of the operation cycle. Results suggest that the main effect of BPA on AS was to increase the generation of microbial soluble products. This work helps to understand the relationship between the biodegradation of BPA and readily biodegradable substrates.  相似文献   

16.
Bisphenol A (BPA) is an endocrine disrupting agent that can alter the normal gonadal steroid-sensitive sexual differentiation of the brain and behavior. While reproductive behavior and physiology are known to be altered by perinatal exposure to this compound, less is known about BPA's effects on sex differences in learning and measures of affect. In order to evaluate the effects of perinatal BPA treatment on learning and affect in adulthood, we exposed rats to one of five doses of BPA through gestation and lactation then examined adult behavior in the Morris Water Maze (MWM), the Elevated Plus Maze (EPM) and the Forced Swim Test (FST). No effect of BPA was observed in the MWM, but on both the EPM and FST, low doses (5 μg/kg) of BPA eliminated sex differences found between controls; furthermore, a non-monotonic dose-response observed in previous studies was confirmed for these tasks. Overall, our study adds to the growing data suggesting that BPA interferes with the normal development of affective behaviors in a non-linear, dose-dependent manner.  相似文献   

17.
18.
Burst-promoting activity (BPA) was measured in the sera from 31 children with aplastic anaemia (AA). BPA levels were elevated in most of the children with AA (65.2%), the mean value (137.7 +/- 18.4%) being significantly higher than that in normal children (69.6 +/- 9.4%), in children in the recovery period and in children with non-aplastic anaemia. There was a negative relationship between the BPA level in children with AA and the peripheral haemoglobin concentration. The BPA level was higher in those whose duration of illness was shorter than 1 year. In three cases of AA caused by chloramphenicol and benzene hexachloride and one case of congenital pure red cell AA, the BPA level was not elevated. Eleven patients received fetal liver cell suspensions intravenously (FLI). After FLI the BPA level in their sera was significantly reduced. According to these results, it appears that the elevation of BPA level is a special phenomenon of AA. The measurement of BPA in serum is helpful for differentiation between AA and other kinds of anaemia. The elevation of the BPA level in serum is a biological compensation for the haematopoietic disorder, and the measurement of BPA in the serum of patients with AA may be helpful in evaluating the haematopoietic condition.  相似文献   

19.
目的:研究体外大鼠睾丸支持细胞紧密连接蛋白(SCJP)在类雌激素-双酚A(BPA)干扰下的损伤机制。方法:对Wistar大鼠睾丸支持细胞(Sertoli细胞)离体原代培养4-5d,通过双室培养模型建立体外紧密连接(TJ)渗透性屏障,并测量其跨上皮电阻值(TER)反应紧密连接结构的形成及BPA对紧密连接的损害程度。设溶剂(DMSO)做阴性对照,以终浓度为25μM、100μM的BPA作用于支持细胞24h,MTT法测不同浓度BPA作用的Sertoli细胞增殖活性。Western bloting观察occludin、ZO-1、Cx43表达的变化。结果:成功分离并培养Wistar大鼠睾丸支持细胞,并建立良好的体外TJ屏障模型。双室培养支持细胞上皮TER值在培养的d4达到顶峰,然后在d4-9维持相对较稳定的状态,d4以200μM,100μM,25μM BPA染毒,分别于染毒后24,48,72,96和120h测TER:与DMSO溶剂对照组相比,200μM,100μM的BPA组TER值明显下降(P<0.05),而25μM的BPA组在染毒后TER值无明显变化(P>0.05)。MTT结果显示:经不同浓度BPA作用24h后,Sertoli细胞的吸光度(OD值)随着染毒剂量的增加而逐渐降低。102、103μM浓度组与溶剂对照组有显著性差异(P<0.05),而10-2、10-1、100、101μM组和溶剂对照组无显著性差异(P>0.05)。Western blot结果显示:occludin、ZO-1、Cx43在各剂量组均有表达,与溶剂对照组相比,occludin、ZO-1表达均分别随作用剂量的增加而降低:25μM组、100μM组与溶剂对照组相比,差异均存在显著性(P<0.05);100μM组与25μM组相比,差异亦存在显著性(P<0.05)。Cx43的表达却随染毒剂量的增加而增加,与溶剂对照组相比,25μM组表达无明显增加(P>0.05),而100μM组则明显增加(P<0.05);与25μM组相比,100μM组表达明显增加(P<0.05)。结论:双酚A可通过损伤支持细胞连接蛋白正常表达,破坏了TJ屏障渗透性,从而影响正常的精子形成过程。  相似文献   

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