中国地鼠线粒体D-loop基因的克隆及序列分析

本试验根据已知相近物种动物基因序列设计引物,PCR扩增获得中国地鼠线粒体D-loop基因序列。采用DNAStar软件计算序列碱基组成,分析遗传变异情况。用MEGA 4.1软件计算物种间遗传距离,采用邻接法(NJ)、最小进化法(ME)构建系统进化树。结果表明,中国地鼠线粒体D-loop区序列全长为867 bp,碱基A、T、C、G的含量分别为29.53%、31.49%、26.07%、12.92%,中国地鼠与啮齿类动物有相似的碱基组成。系统进化树结果显示,中国地鼠与金黄地鼠亲缘关系较近,与大鼠的关系最远,与传统的分类相一致。所获得的中国地鼠D-loop基因可作为种间遗传变异研究的标记,研究结果为进一步研究中国地鼠的群体遗传结构奠定了基础。     

Setting New Immunobiological Parameters in the Hamster Model of Visceral Leishmaniasis for <Emphasis Type="Italic">In Vivo</Emphasis> Testing of Antileishmanial Compounds

To establish suitable immunobiological parameters for in vivo testing of new antileishmanial compounds in the golden hamster model of visceral leishmaniasis, two groups of 8 animals were infected each with 10⁵ or 10⁷ stationary promastigotes by the intracardiac route and the clinical and immunoparasitological features were monitored up to day 155 after infection. All animals became infected at both doses, although significant differences were observed between parasite burdens in liver and spleen. The mean number of parasites in animals infected with 10⁷ promastigotes increased by 9.5 times in liver and by 43.1 times in spleen compared with those infected with 10⁵ promastigotes. In animals given the higher dose, the outcome of the disease occurred between days 75 and 90 after infection, whereas no signs of disease were apparent in those given the lower infecting dose. Positive antibody (IgG) responses were detected earlier (week 5–7 after infection) in animals infected with the higher dose than in those infected with the lower dose (week 8–10 after infection), but these responses did not correlate with individual parasitological loads in liver and spleen. An inverse correlation was observed between infecting doses and in vitro spleen lymphocyte proliferation against mitogens (ConA). The proportion of CD4⁺ and CD19⁺ spleen cell increased in animals given the higher infection, whereas it decreased in those given the lower infection compared to naive controls.     

Some impacts of low and medium head weirs on downstream fish movement in the Murray–Darling Basin in southeastern Australia

Abstract –  This article reports on the findings of a study undertaken within the Murray-Darling River Basin in southeastern Australia, which investigated the impact of weirs on downstream fish movement. Downstream fish movement was monitored at Kennedy's Weir (an overshot, 2 m high weir) on the Broken Creek and Torrumbarry Weir (an undershot, 6.5 m high weir) on the Murray River. A trap used to sample Kennedy's Weir indicated that fish travelled downstream over this weir without sustaining injury or death. A follow-up study, whereby fish were captured below the two respective weirs and translocated upstream where they were radio tagged and released, indicated that while a few fish travelled downstream past the weirs on their return movements back to their home range areas, most were reluctant to do so. This study demonstrates that low-level weirs may inhibit downstream fish movement, and enhancement of downstream fish passage for potamodromous fish species warrants further investigation.     

白马雪山自然保护区北部曲宗贡金妞河流域植被类型调查研究

白马雪山自然保护区北部曲宗贡金妞河流域是保护区海拔最高的区域,拥有丰富多彩的植被类型,孕育和保存着多种珍稀药材、高山花卉等,同时也是特有动植物的极限生境拥有地,是白马雪山保护区的精华所在和缩影。在2009～1012年的不同时段,对126个样地植被进行调查,将流域的植被分为4个植被型6个植被亚型20个群系29个群落,分析该区域多样性植被类型的存在价值和保护价值。     

中国大青金色花叶病毒浙江分离物全基因组序列测定与分析

<正>大青(Clerodendrum cyrtophyllum Turcz),别名路边青、淡婆婆、臭叶树,为马鞭草科(Verbena officinalis Linn)大青属(Clerodendrum)野生落叶灌木,常生长在山地林下、平原、丘陵和溪谷旁,我国江苏、安徽、河北、河南、浙江等地为主产区。大青用途广泛,叶片可萃取靛蓝作为染料,嫩叶可食用,     

金鲳鱼肉和罗非鱼皮明胶改善罗非鱼碎肉鱼糜品质

为了改善罗非鱼碎肉鱼糜制品的品质,研究添加金鲳鱼肉和罗非鱼皮明胶对罗非鱼碎肉鱼糜制品品质的影响。将少量金鲳鱼肉与罗非鱼碎肉混合,制作成鱼糜(金鲳鱼肉质量分别占复合鱼糜总质量的0%、5%、10%、15%、20%),研究鱼糜制品品质的变化规律。通过检测样品的质构、凝胶强度、出水率及颜色发现,随着复合鱼糜中金鲳鱼肉含量的上升,复合鱼糜制品的硬度、胶着性、咀嚼性、弹性、内聚性、凝胶强度、白度均呈现上升趋势,但出水率无显著变化。进一步研究,将罗非鱼鱼肉和金鲳鱼鱼肉以一定比例混合,制作成复合鱼糜,然后加入不同量的明胶,研究复合鱼糜制品品质的变化规律发现,将明胶添加到复合鱼糜制品中会使鱼糜制品的硬度、胶着性、咀嚼性、凝胶强度、白度均上升,出水率下降,但鱼糜的弹性、内聚性、破断距离等差异不显著。试验结果表明,金鲳鱼肉和罗非鱼皮明胶可以用于罗非鱼碎肉鱼糜制品品质的改良。研究结果为改善罗非鱼碎肉鱼糜制品的品质提供了参考。     

亚洲龙鱼品系及鉴别

为让人们更加全面认识和了解亚洲龙鱼,对亚洲龙鱼的品系及其鉴定方法进行介绍.亚洲龙鱼有金龙、红龙和青龙三大类,市场上繁杂的龙鱼种类都是从这3种衍化而来的.龙鱼由体色、体型、鳞片光泽及色块分布、鳍条形状、口须及鳞片的完整度、眼睛的角度及光泽、嘴型、鳃盖、呼吸及游泳姿态等特征决定其品质的优劣.     

Strategies of behavior,energetic and thermogenesis of striped hamsters in response to food deprivation

The life history of many animals includes periods of food shortage. Two behavioral strategies are involved in small mammals in response to food shortage: an increase in activity behavior, representing the increased foraging or migratory behavior, and a decrease in activity level, serving as a mechanism for conserving energy. However, it is uncertain whether animals adopt both strategies in response to food shortage, and whether hormone and neuroendocrine mechanisms are involved in both strategies. In the present study, changes in behavior and metabolic rate were examined in food‐deprived striped hamsters (Cricetulus barabensis). The effects of leptin supplement on activity behavior, metabolic rate and hypothalamic neuropeptide gene expression were also examined. The behavior of food‐deprived hamsters significantly changed with photoperiod phases: with increasing activity during the dark phase compared to those fed ad libitum, whereas decreasing activity and simultaneously increasing resting behavior during the light phase. Resting metabolic rate, body mass, and masses of fat depots and digestive tracts significantly decreased in food‐deprived hamsters compared with ad libitum controls. Leptin supplement tended to attenuate the increased activity in the dark phase. Gene expression of hypothalamic neuropeptide Y (NPY) was significantly upregulated in food‐deprived hamsters, while was significantly attenuated by exogenous leptin. These findings suggest that both behavior strategies are important behavioral adjustments in free‐living animals to cope with food shortage. Leptin and hypothalamic NPY gene expression may be involved in the adjustments of physiology and behavior in animals demonstrating a hyperactivity strategy in response to food shortage.     

保靖黄金茶红茶发酵工艺研究

以保靖黄金茶群体品种一芽二、三叶及同等嫩度的对夹叶鲜叶为原料,利用红茶自动发酵机在28℃条件下进行不同发酵时间与不同保湿措施处理,对加工的红茶进行感官审评及儿茶素与茶黄素含量分析。结果表明:当发酵时间增加到240 min后,儿茶素向茶黄素转化趋势明显;其中感官审评得分最高的为经发酵240 min及盖布处理的茶样,茶汤颜色红匀明亮、口感醇厚,儿茶素与茶黄素的含量分别为38.650 4、13.493 5 mg/g。所有发酵进程中进行湿纱布覆盖保湿处理,其茶黄素含量均较未盖布处理茶样增加显著,茶汤亮度明显较亮,滋味更加浓厚。