Male heterogametic sex determination in Rana dybowskii based on sex-linked molecular markers

Identifying the mechanism for sex determination in amphibians is challenging. Very little is known about sex determination mechanisms of Rana dybowskii, a species of importance to evolutionary and conservation biology. We screened for sex-linked molecular markers in R. dybowskii in China using target region amplification polymorphism with 2 fixed primers against the sequences of Dmrt1. We found 2 male-linked molecular markers in R. dybowskii, which were 222 bp and 261 bp long. The detection rates of 222 bp marker in males form Xinglong, Huadian, and Dandong were 93.79%, 69.64%, and 13.64%, respectively, while the rate in females from Huadian was 27.50%. Besides, the detection rates of 261 bp marker in the above 3 regions were only observed in males at the rate of 93.79%, 87.50%, and 32.73%, respectively. The inheritance patterns of sex-linked molecular markers showed that the 2 sex-linked molecular markers were heterozygous. Compared to the XY-male parent, progeny from XX-pseudo-male parent possessed lower sex reversal ratio at the same rearing temperature, and the proportion of female froglets from an XX-pseudo-male parent was more than 95% at low rearing temperature (15°C). Our findings suggest that R. dybowskii displays male heterogamety, and the 2 sex-linked molecular markers may have a guiding significance for the protection and utilization of R. dybowskii.     

水稻黑条矮缩病毒S6片段的序列多样性与进化分析

<正>0 引言植物RNA病毒在进化中具有快速变异的能力,有利于病毒扩大寄主范围甚至进化为新病毒[1]。突变和重组是植物RNA病毒变异和遗传多样性的共同进化因素,是群体基因变异的最初来源[2]。由灰飞虱传播的水稻黑条矮缩病毒(Rice black streaked dwarf virus, RBSDV) 属于呼肠孤病毒科(Reoviridae)斐济病毒属(Fijivirus),能引发玉米粗缩病和水稻黑条矮缩病。     

一起母牛采食马铃薯皮引起亚硝酸盐中毒误诊案的思考

为切实加强动物中毒性疾病的诊断处置能力,防止因诊断失误、处置不当导致动物死亡现象的发生。本文就一起母牛采食马铃薯皮引起亚硝酸盐中毒误诊案的诊断处置过程进行讨论分析,提出了相应的诊断处置意见,供广大兽医同仁在实际诊断过程中借鉴应用。     

Effect of compound salvae-dropping-pill on intracellular free calcium concentration of cultured rat myocardial cells in case of hypoxia and reoxygenation

AIM:To examine the effect of compound salvae-dropping-pill (CSDP) on intracellular free calcium in cultured rat myocardial cells subjected to hypoxia and reoxygenation.METHODS:The Fluo- 3/AM was applied to probe intracellular calcium concentration and the fluorescent intensity was detected using laser confocal microscopy technique.RESULTS:Fluorescent intensity in hypoxia plus CSDP group was significantly lower (1 217.78±312.07) than that of hypoxia group (1 509±508.48), and the Fluorescent intensity of hypoxia/reoxygenation plus CSDP group was also markedly lower (1 567.91±577.61) than that of hypoxia/reoxygenation group (1 617.60±477.53).CONCLUSION:The cultured rat myocardial cells could be effectively protected by administration of CSDP in case of hypoxia and reoxygenation through decreasing the intracellular calcium concentration.     

面向老龄化社会的户外环境植物景观与健康效益评价模型建构

为了促进国内基于健康视角下户外植物景观可量化评价机制的形成与完善,归纳总结了健康景观以及普通植物景观中广泛存在的对人身心健康有促进作用的因素——植物的健康效益。从植物景观对人身心健康的影响机制手,分析户外景观环境中健康性要素构成,深入探究植物景观与老年人身心健康的作用机理,并初步构建了基于植物健康效益的适老性户外植物景观评价指标体系。     

广州市公园绿地地被植物应用现状调查

为了解广州地区地被植物的应用情况,文章以广州市区内 10 个规模较大、管理养护水平较高的城市公园为研究对象,对其公园内的地被植物资源的种类、应用频度、应用方式进行统计与记录。广州市公园绿地常应用地被植物共 102 种,隶属于 53 科,地被植物种类拥有较高丰富度,总结了广州市公园绿地地被植物应用类型,分析目前存在的问题,并提出注重华南乡土地被植物的开发与推广应用建议。     

我国脲醛树脂制备技术研究概述

介绍了我国近年来脲醛树脂制备技术和实际应用概况,总结了生产实践中较为实用的树脂制备和改性方法,探讨了脲醛树脂目前存在问题,并指出发展方向。     

保水剂对千里光种子萌发及幼苗生长的影响研究

为探明保水剂对千里光(Senecio scandens)种子萌发、幼苗生长的影响以及最佳使用量,采用室内盆栽试验,研究了5个梯度的保水剂浓度[0(CK)、0.10%、0.20%、0.30%、0.40%]对千里光种子萌发及幼苗生长的影响。试验结果表明,添加适宜浓度的保水剂可提高千里光种子发芽率,最佳保水剂浓度为0.30%,较对照提高了7.62%。添加保水剂可以提升千里光幼苗生物量、株高与根系长度,株高随保水剂浓度增加呈先增加后下降趋势,根系长度随保水剂浓度增加而增加,在0.40%浓度处理达到最大值。在采用千里光进行绿化时建议加入浓度为0.30%的保水剂,有利于提高其成活率及绿化效果。     

千岛湖森林康养基地发展路径探析——基于千岛湖龙川湾的调查研究

国家相关管理部门联合提出按照“环境优良、服务优质、管理完善、特色鲜明、效益明显”的要求建设一批国家森林康养基地。以浙江千岛湖龙川湾为例,分析其森林资源、地理区位、产业链、发展规模、社会合作、管理保障、三大效益等方面建设森林康养基地的优势,整合提升游憩观赏、研学文化、垂钓休闲、扶犁耕地、康养保健、疗养康复、健身拓展区域空间布局与发展举措,从康养体验、休闲体验、运动健身等方面增强千岛湖龙川湾森林康养基地功能,推进森林康养产业发展。