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991.
Caviomorphs are a clade of South American rodents recorded at least since the early Oligocene (> 31.5 Ma) that exhibit ample eco-morphological variation. It has been proposed that phylogenetic structure is more important than ecological factors for understanding mandibular shape variation in this clade. This was interpreted as a result of the long-standing evolutionary history of caviomorphs and the early divergence of major lineages. In this work, we test this hypothesis through the analysis of morphological variation in the mandible of living and extinct species and compare this information with that obtained through comparative phylogenetic analyses. Our results support the hypothesis of early origin of mandibular variation; moreover, they suggest the conservation of early differentiated morphologies, which could indicate the existence of constrained evolutionary diversification.  相似文献   
992.
The Brazilian Atlantic Forest is one of the richest biodiversity hotspots of the world. Paleoclimatic models have predicted two large stability regions in its northern and central parts, whereas southern regions might have suffered strong instability during Pleistocene glaciations. Molecular phylogeographic and endemism studies show, nevertheless, contradictory results: although some results validate these predictions, other data suggest that paleoclimatic models fail to predict stable rainforest areas in the south. Most studies, however, have surveyed species with relatively high dispersal rates whereas taxa with lower dispersion capabilities should be better predictors of habitat stability. Here, we have used two land planarian species as model organisms to analyse the patterns and levels of nucleotide diversity on a locality within the Southern Atlantic Forest. We find that both species harbour high levels of genetic variability without exhibiting the molecular footprint of recent colonization or population expansions, suggesting a long-term stability scenario. The results reflect, therefore, that paleoclimatic models may fail to detect refugia in the Southern Atlantic Forest, and that model organisms with low dispersal capability can improve the resolution of these models.  相似文献   
993.
在社会需要和科技进步的双重推动下,"3R"原则和动物试验替代方法正在从道德理念向实验技术转变。站在全球科技发展的高度,结合我国实验动物替代领域的现状和未来趋势,利用MSSQLServer2000构建中国替代方法研究评价中心共识平台,管理信息数据库,用WEB技术将数据库与internet WWW(WorldWideWeb)页面连接,构成动态的咨询平台和信息数据网络查询系统。该共识平台的建立为国内从事实验动物及替代方法研究应用的用户提供了便利,起到了国内外替代技术交流的桥梁作用。  相似文献   
994.
组织学技术教学的探索与实践   总被引:1,自引:0,他引:1  
组织学技术是多学科研究工作的基础。在组织学技术课程教学过程中,如何提高听课效果,使学生在以后的科研活动中能够灵活运用所学知识和技术是这门课程最关键的问题。本文就近两年我们在组织学技术教学实践过程中进行的几方面尝试作一介绍。  相似文献   
995.
Wang C  Ye M  Han G  Chen R  Zhang M  Jiang X  Cheng K  Wang F  Zou H 《Proteomics》2011,11(17):3578-3581
Multiple residues with consensus sequence, i.e. motif, on proteins are closely related to protein function. However, there is no effective method for targeted analysis of such proteins. The challenge for analysis of these classes of proteins by MS is how to selectively enrich peptides containing consensus sequence from protein digest. Although enrichment of peptides containing one type of amino acid residue was successfully achieved by chemically labeling followed by chromatographic isolation, however, it is almost impossible to label and isolate signature peptides containing multiple residues with consensus sequence by chemical approach. Herein, we developed an enzymatic approach based on the specific recognition between enzyme and its substrates to enrich such peptides. This approach was realized by modification of a residue in the consensus sequence via enzyme that can recognize the sequence followed by the isolation of the modified peptides. cAMP-dependent protein kinase was used to validate this approach and 168 peptides containing consensus motif were identified with selectivity of 67.2%. Those peptides resulted in the identification of 88 proteins with consensus sequence from serum sample. As this motif-oriented peptide enrichment approach allows targeted analysis of a subset of proteins with consensus sequence, it will have broad application in biological studies.  相似文献   
996.
James P 《Proteomics》2011,11(18):3596-3597
The most critical functions of the various proteomics organisations are the training of young scientists and the dissemination of information to the general scientific community. The education committees of the Human Proteome Organisation (HUPO) and the European Proteomics Association (EuPA) together with their national counterparts are therefore launching the International Proteomics Tutorial Programme to meet these needs. The programme is being led by Peter James (Sweden), Thierry Rabilloud (France) and Kazuyuki Nakamura (Japan). It involves collaboration between the leading proteomics journals: Journal of Proteome Research, Journal of Proteomics, Molecular and Cellular Proteomics, and Proteomics. The overall level is aimed at Masters/PhD level students who are starting out their research and who would benefit from a solid grounding in the techniques used in modern protein-based research. The tutorial program will cover core techniques and basics as an introduction to scientists new to the field. At a later stage the programme may be expanded with a series of more advanced topics focussing on the application of proteomics techniques to biological problem solving. The entire series of articles and slides will be made freely available for teaching use at the Journals and Organisations homepages and at a special website, www.proteomicstutorials.org.  相似文献   
997.
Abbaraju NV  Cai Y  Rees BB 《Proteomics》2011,11(21):4257-4261
Reliable proteomic analysis of biological tissues requires sampling approaches that preserve proteins as close to their in vivo state as possible. In the current study, the patterns of protein abundance in one‐dimensional (1‐D) gels were assessed for five tissues of the gulf killifish, Fundulus grandis, following snap‐freezing tissues in liquid nitrogen or immersion of fresh tissues in RNAlater®. In liver and heart, the protein profiles in 1‐D gels were better preserved by snap‐freezing, while in gill, the 1‐D protein profile was better preserved by immersion in RNAlater®. In skeletal muscle and brain, the two approaches yielded similar patterns of protein abundance. LC‐MS/MS analyses and database searching resulted in the identification of 17 proteins in liver and 12 proteins in gill. Identified proteins include enzymes of energy metabolism, structural proteins, and proteins serving other biological functions. These protein identifications for a species without a sequenced genome demonstrate the utility of F. grandis as a model organism for environmental proteomic studies in vertebrates.  相似文献   
998.
‘教学型’高校教师的主要工作是教学,科研工作处于时断时续的状态。针对以上现实,本文指出了“教学型高校”加大科研力度的必要性,并就目前的科研现实提出切实可行的改进措施。①教学与科研不是独立的两个方面,而是相互促进的一个整体,加大‘教学型’高校的科研力度可以达到教学、科研的互利双赢。科研应该逐渐成为‘教学型高校’教师的重要工作内容。②重视科研也是重视教学,提高教学质量以及围绕教学进行的评估、教改等各项举措,也应该从加大科研力度的角度进行:教师有了科研工作,自然需要学生参与;而学生加入到教师的科研活动,不仅是对学生动手能力、创新意识的最好培养,更将明显提高学生学习理论知识的积极性,提高听课效率。③改善‘教学型高校’科研工作的现状,可从设立研究型教师岗位和减少行政指令性活动等方面入手。  相似文献   
999.
魏红霞  张葵  李雷  朱宏  顾光煜  王丽 《生物磁学》2011,(9):1767-1770
目的:比较不同方法检测糖尿病患者血清LDL-C水平,为临床诊疗提供准确可行的检验方法。方法:采用沉淀法、匀相法、电泳法及超速离心法对233例糖尿病患者和102例健康人群的血清LDL-C水平进行测定,比较各方法之间的相关性,同时分析导致结果差异的因素。结果:四种方法检测健康人群LDL-C水平,结果间无统计学差异(P〉0.05);糖尿病组,当TG≤2.26mmol/L时,四种方法检测LDL-C结果间相关性良好。高胆红素、血红蛋白、高TG及乳糜等干扰因素存在时,与其他方法相比,电泳法和超速离心法检测血清LDL-C结果受影响较小(P〉0.05)。结论:超速离心法虽耗时、价格贵,但仍为检测LDL-C的经典方法,电泳法受高胆红素、血红蛋白、高三酰甘油等干扰因素的影响相对较小,适用于糖尿病合并高血脂患者血清LDL-C水平检测。  相似文献   
1000.
滑玮  陈必良  杨红 《生物磁学》2011,(9):1786-1788
目的:将CBS教学法运用于妇产科学的教学中,探讨其教学效果。方法:在妇产科学教学中,将我校2005级临床医学160名本科学生分为试验组(CBS教学法)和对照组(传统讲授方法)。结果:学科考试中,试验组的平均分数显著高于对照组(P〈0.01)。结论:CBS教学法是行之有效并且切实可行的,对提高妇产科学的教学质量、提高学生的综合能力具有积极的意义。  相似文献   
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