基于ISSR标记的辽宁4个东北林蛙种群遗传多样性分析

辽宁是东北林蛙Rana dybowskii主要分布地之一,种群数量巨大,其群体遗传多样性有待评估.本研究应用ISSR标记技术对东北林蛙4个种群105个样本进行研究,5个引物共获得44条清晰谱带,4个种群的多态位点率均大于75%,Nei's基因多样性为0.2851,Shannon信息指数为0.4476,显示了较高的遗传多样性.对遗传分化系数、Nei's遗传距离、AMOVA分子变异巢式方差分析和F-统计量等遗传参数的统计结果表明,辽宁东北林蛙种群间已经出现一定程度的遗传分化,分析认为,自然屏障(高山和平原等)以及栖息地片段化是其遗传分化形成的主要因素.     

Haemosporidian Parasites of Antelopes and Other Vertebrates from Gabon,Central Africa

Re-examination, using molecular tools, of the diversity of haemosporidian parasites (among which the agents of human malaria are the best known) has generally led to rearrangements of traditional classifications. In this study, we explored the diversity of haemosporidian parasites infecting vertebrate species (particularly mammals, birds and reptiles) living in the forests of Gabon (Central Africa), by analyzing a collection of 492 bushmeat samples. We found that samples from five mammalian species (four duiker and one pangolin species), one bird and one turtle species were infected by haemosporidian parasites. In duikers (from which most of the infected specimens were obtained), we demonstrated the existence of at least two distinct parasite lineages related to Polychromophilus species (i.e., bat haemosporidian parasites) and to sauropsid Plasmodium (from birds and lizards). Molecular screening of sylvatic mosquitoes captured during a longitudinal survey revealed the presence of these haemosporidian parasite lineages also in several Anopheles species, suggesting a potential role in their transmission. Our results show that, differently from what was previously thought, several independent clades of haemosporidian parasites (family Plasmodiidae) infect mammals and are transmitted by anopheline mosquitoes.     

双源CT冠状动脉血管成像诊断心肌桥的价值探讨

目的：研究双源CT冠状动脉血管成像诊断心肌桥的临床价值。方法：选择260例具有典型心前区不适的患者进行双源CT冠脉血管成像检查,观察其发生部位,测量其长度和深度并进行分析。结果：260例受检患者中,62例共70段存在心肌桥,检出率达20.76%,高于文献报道的检出率18.2%。所有心肌桥均发生于左前降支,其中近段17段（24.4%）,中段43段（61.4%）,远段10段（14.2%）。心肌桥平均长度为15.8±6.4mm,深度为1.4±0.85mm。结论：双源CT冠状动脉血管成像因其便捷无创,不受心率严格限制且价格低廉可作为心肌桥筛查的理想检查手段。     

黑皮质素受体-4调节通路的研究进展

黑皮质素系统来自阿片-促黑素细胞皮质素原,在中枢摄食行为和能量平衡代谢中起到重要作用,此系统生理功能的发挥主要通过与下丘脑神经元细胞上特定膜受体（黑皮质素受体）结合完成。黑皮质素受体（MCR）有五种亚型（MC1R-MC5R）,其中参与体重调节的受体主要是黑皮质素受体3（MC3R）和黑皮质素受体4（MC4R）。MC4R属于G蛋白耦联受体,具有七次跨膜结构。作为一种膜受体,MC4R发挥体重调节作用,一方面受外界激动剂或拮抗剂的调节;另一方面,此受体活化后会影响到细胞内的信号调节通路。研究MC4R的功能首先要了解受体的结构,本文对G蛋白耦联受体的结构进行了较详细的叙述,MC4R经信号调节通路,激活腺苷酸环化酶,增加cAMP的浓度,最终通过影响细胞内基因的转录和翻译,来调节体重和能量的消耗。     

中国西北沙漠夜间活动的东鳖甲属昆虫二新种(鞘翅目:拟步甲科:漠甲亚科)

记述中国西北地区东鳖甲属2新种:巴丹东鳖甲A.badainica Ba,Ren&Liu sp.nov.和古尔班东鳖甲A.gurbantunggutica Ba&Ren sp.nov.,提供了主要鉴别特征和形态图,并简要讨论了其昼夜活动规律.     

犬MC1R基因T105A基因座多态性及 与毛色性状相关性的研究The

为了检测犬MC1R基因T105A基因座的多态性,并分析该多态性与犬毛色表型的相关性,抽取111只外科手术学实验用杂种犬血液并提取DNA,记录毛色表型。采用PCR-RFLP技术,对MC1R基因T105A基因座进行基因多态性分析,并对该基因座DNA进行克隆测序;用二元变量相关分析的统计学方法分析基因座多态性与毛色性状之间的相关性。经PCR-RFLP分析结果表明,T105A基因座序列具有多态性,表现为A、B二个等位基因和AA、AB及BB 3种基因型。A、B等位基因频率分别为72.97%和27.03%,基因杂合度（H）为0.39。基因型AA频率为55.86%,BB为9.91%,AB为34.23%。对T105A多态性片段DNA克隆测序后发现,MC1R基因在编码第105位氨基酸的密码子第一个碱基存在由G到A的单碱基突变,该突变导致第105位氨基酸发生由丙氨酸向苏氨酸的改变。统计分析结果表明MC1R基因T105A基因座的多态性与毛色性状不存在显著的相关性,这可能是由于外科手术学实验用犬是杂种犬,其遗传背景不同所致,尚须在纯种犬群体中进一步研究MC1R基因对毛色的影响。 Abstract: In order to detect the polymorphism of T105A in MC1R gene in dogs and to analyze the relationship between the genetic polymorphisms and phenotypes of dog coat color, the blood samples of 111 cross-breed dogs were taken and their genomic DNAs were extracted. The phenotypes of dog coat color were recorded. The T105A locus of MC1R gene in the canine was detected through the technology of PCR-RFLP. Furthermore, the polymorphic fragments at T105A were sequenced. The relationships between the polymorphism of T105A and coat color trait were analyzed by the statistical methods of bivarate correlation analysis. By the method of PCR-RFLP, the T105A polymorphism was found with two alleles A and B and three genotypes AA, AB and BB. The frequencies of two alleles were 72.97% and 27.03%, respectively. The heterozygosity of T105A locus was 0.39. The frequencies of three genotypes were 55.86%, 34.23% and 9.91%, respectively. According to the results of sequencing, one base change from G to A at the position 105 was found at T105A locus and it altered amino acid at the position 105 from alanine to threonine. According to the statistical analysis, no significant association between the polymorphism of MC1R gene and the coat color was found and the result may be due to the differences of genetic background. Further research on MC1R gene should be done in pure breed dogs.     

3种香薷属植物染色体数目与核型分析

参照植物根尖细胞学研究的方法标准,对香薷属3种(5个居群)植物进行核形态学分析。结果表明:(1)从染色体数目看,密花香薷2居群染色体数目2n=16;野苏子2居群染色体数目2n=20,染色体数目和倍性与前人报道的一致;毛穗香薷染色体数目2n=10为首次报道。(2)聚类分析结果显示,3种(5居群)植物中野苏子和密花香薷亲缘关系较近;结合现有报道数据分析表明,该属植物仅有2种倍性(二倍体和四倍体),且二倍体占主导地位。(3)核型参数分析表明:密花香薷的稻城无名山居群1核型公式为2n=2x=16=14m+2sm,居群2为2n=2x=16=16m,着丝粒指数(CI)分别为39.57和42.32,不对称系数AI值分别为2.75和2.87,核型不对称性都为1A型;毛穗香薷的核型公式为2n=2x=10=10m,着丝粒指数(CI)为41.76,不对称系数AI值为5.25,核型不对称性为1B型;野苏子的昆明西山居群核型公式为2n=2x=20=14m+6sm,聂拉木樟木沟居群为2n=2x=20=16m+4sm,着丝粒指数(CI)分别为38.49和40.97,不对称系数AI值为4.20和4.30,核型不对称性为1B型和2B型。     

The Dutch N-cascade in the European perspective

The Netherlands is "well known" for its nitrogen problems; it has one of the highest reactive nitrogen (Nr) emission densities in the world. It is a small country at the delta of several large European rivers. Ever since the industrial revolution, there has been a growing excess of nutrients and related emissions into the atmosphere (ammonia, nitrogen oxides and nitrous oxide) and into groundwater and surface water (nitrate), leading to a large range of cascading environmental impacts. Vehicular traffic, sewage and animal husbandry are the main sources of oxidized and reduced forms of Nr. This paper provides an overview of the origin and fate of nitrogen in the Netherlands, the various reported impacts of nitrogen, the Dutch and European policies to reduce nitrogen emissions and related impacts. In addition, ways are presented to go forward to potentially solve the problems in a European perspective. Solutions include the improvement of nitrogen efficiencies in different systems, technological options and education.     

用酵母双杂交系统筛选影响apo-AI和SR-BI相互作用的苦豆子活性成分

本文通过将苦豆子总提取物及其分离得到的10个组分加入含有AH109菌株(携带大鼠apo-AI及其受体SR-BI全基因)的培养基中,利用报告基因半乳糖苷酶活力有无变化来寻找能够促进大鼠载脂蛋白apo-AI及其受体SR-BI相互作用的激动剂.经测试,我们观察到苦豆子总提取物(K-1),在上述系统中能显著增强这两种蛋白的相互作用.继续用硅胶柱层析方法从k-1中分出10个组分后,利用酵母双杂交系统再次筛选,发现有五个组分能增强两种蛋白的相互作用,(与空白对照组相比其中有两个组分有极显著差异)另外三个组分显著地抑制上述两种蛋白的相互作用,剩下的两个组分则没有差异.该实验还提示该酵母双杂交系统可能成为一种跟踪具有调脂功能的先导化合物的有效方法.