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11.
藏东南德姆拉山东坡及察隅河谷的蚂蚁群落   总被引:1,自引:0,他引:1  
蚂蚁隶属于昆虫纲( Insecta)膜翅目(Hymenoptera)蚁科(Formicidae),是地球上分布最广泛、种类和数量最多的社会性昆虫,除了地球的两极及雪线之上,陆地上几乎都有蚂蚁的踪迹.蚂蚁不仅具有药用、食用及研究价值,还有改良土壤、帮助植物传粉、传播植物种子、防治害虫等功用(徐正会,2002).此外蚂蚁还是指示生物多样性和环境变化的重要类群(Andersen,1990;1995;Alonso,2000;Kaspari et al.,2000). 20世纪至今,国内有关蚂蚁物种多样性的研究报道呈增长趋势.国外蚁类学家Mayr (1889)、Forel (1906)、Ruzsky (1914)、Donisthorpe (1929)、Menozzi(1939)、Eidmann(1941;1942)、Dlussky( 1965)、Collingwood (1970)、Kohout (1994)、Radchenko等(1999)等报道过西藏的蚂蚁种类及地理分布.我国蚁类学家唐觉等( 1982;1993)、周善义( 2004)分别报道过西藏墨脱、喜马拉雅山区和雅鲁藏布大峡谷的蚂蚁(于娜娜等,2011).  相似文献   
12.
Fungal diseases are a major constraint for wheat production. Effective disease resistance is essential for ensuring a high production quality and yield. One of the most severe fungal diseases of wheat is Septoria tritici blotch (STB), which influences wheat production across the world. In this study, genomewide association mapping was used to identify new chromosomal regions on the wheat genome conferring effective resistance towards STB. A winter wheat population of 164 North European varieties and breeding lines was genotyped with 15K single nucleotide polymorphism (SNP) wheat array. The varieties were evaluated for STB in field trials at three locations in Denmark and across 3 years. The association analysis revealed four quantitative trait loci, on chromosomes 1B, 2A, 5D and 7A, highly associated with STB resistance. By comparing varieties containing several quantitative trait loci (QTL) with varieties containing none of the found QTL, a significant difference was found in the mean disease score. This indicates that an effective resistance can be obtained by pyramiding several QTL.  相似文献   
13.
This study empirically investigates the direct and indirect (spillover) effects of three types of industrial agglomeration with different cognitive distances, namely, industrial specialization, industrial related variety, and industrial unrelated variety, on regional innovation. Accordingly, we applied the concepts of related and unrelated variety and used spatial econometric analysis. Based on panel data of 283 Chinese cities from 2004 to 2016, the empirical results reveal that both industrial specialization and industrial related variety significantly improve regional innovation and produce positive spatial spillover effects on the surrounding regions. However, industrial unrelated variety has a significant negative impact on regional innovation and produces a negative spatial spillover effect on the surrounding regions. Moreover, the direct and indirect effects of the three types of industrial agglomeration on regional innovation between China's coastal and inland cities. The findings have important theoretical and policy implications.  相似文献   
14.
过氧化物氧化还原酶5 (PRDX5)是一种硫氧还蛋白,参与机体多种生物学过程。为了研究PRDX5基因在藏绵羊(Ovis aries)睾丸发育和精子发生过程中的作用,本研究以不同发育阶段(3月龄、1周岁和3周岁)的藏绵羊为研究对象,克隆了PRDX5基因的CDS区,并对其进行生物信息学分析;通过实时荧光定量PCR(qRT-PCR)、Western blot和免疫组织化学染色法,对PRDX5基因在藏绵羊睾丸不同发育阶段的表达和分布进行了检测。结果显示,PRDX5基因CDS区全长659 bp,可编码219个氨基酸;蛋白质结构预测显示PRDX5以α-螺旋为主,无信号肽;系统进化树显示,藏绵羊PRDX5基因与山羊(Capra hircus)亲缘关系最近;1周岁(性成熟期)和3周岁(成年)藏绵羊睾丸中PRDX5 mRNA相对表达量极显著(P <0.01)高于3月龄(性成熟前),但PRDX5蛋白表达量极显著(P <0.01)低于3月龄,且两者在性成熟后趋于稳定;PRDX5蛋白在藏绵羊睾丸不同发育阶段的支持细胞和间质细胞中均有表达。推测PRDX5基因可能通过调节细胞内ROS的水平影响精子发生...  相似文献   
15.
16.
三种镰刀菌引起的板栗内腐病病原菌鉴定   总被引:1,自引:0,他引:1  
为明确板栗内腐病的病原,采用组织分离法分离纯化BL-5、BL-7和BL-9共3株病原菌,通过柯赫氏法则、形态学特征及分子生物学技术对病原菌进行鉴定。结果显示,BL-5在PDA培养基上初期菌丝白色,菌落中心部位有淡红色素,后期菌落逐渐变成深红色,菌落中心可见黄色菌丝;BL-7在PDA培养基上菌落呈白色、绒毛状,分生孢子长椭圆形或梨形、颜色透明、具隔膜;BL-9在PDA培养基上菌丝呈棉絮状,初期菌落呈粉红色,随着菌落的生长,后期菌落颜色逐渐变为浅黄色或褐色,分生孢子中间粗、两头较细长,似镰刀形,弯曲或直立,具有厚垣孢子。BL-5、BL-7、BL-9的ITS序列分别与Fusarium graminearum KJ847741、Fusarium proliferatum MW686898、Fusarium equiseti KU984711的序列同源性均达99%。因此,结合形态学特征和分子生物学特征,判断引起板栗内腐病的3种镰刀菌分别为禾谷镰刀菌(Fusarium graminearum)、层出镰孢菌(Fusarium proliferatum)、木贼镰刀菌(Fusarium equiseti),为板栗内腐病的有效防治提供了依据。  相似文献   
17.

Background

Outcomes of colic treatment are of great interest to clinicians, horse owners and insurers. One commonly used criterion of success is the overall short-term survival rate. This is used as to compare treatments and to measure quality of veterinary care, but may be biased by demographic or social factors such as attitudes towards animal suffering and euthanasia. The aims of this study were to 1) describe and analyse characteristics in horses with signs of colic referred to the University Hospital for Large Animals (UHLA), University of Copenhagen, Denmark over a 10-year period and 2) to compare these rates with those published in other comparable studies.

Results

The overall survival rate for colic horses over the 10-year study period was 68% (confidence intervals (CI): 66–71%; 1087/1588). In the medical group, 1093 horses, short-term survival was 87% (CI: 85–89%). Thirty one % of referred horses were given diagnoses requiring surgical intervention (CI: 29–33%). In this group 32% of the horses were euthanized before surgery (CI: 28–36%; 159/495). Of the surgical cases 27% (CI: 23-31%) were euthanized or died during surgery. Of the horses that recovered from surgery 25% died or were euthanized (CI: 19–32%; 48/189), while 75% survived to discharge (CI: 68–81%).

Conclusions

The short term survival rates of Danish horses with colic were similar or lower to those reported from other countries. Apart from variability of veterinary care, attitudes towards euthanasia vary among the countries, which may bias the outcomes. This study indicates that qualitative interview studies on owners’ attitudes towards animal suffering and euthanasia need to be conducted. Our opinion is that survival rates are not valid as sole indicators of quality of care in colic treatment due to selection bias. If the survival rates are to be compared between hospitals, techniques or surgeons, prospective studies including mutually agreed-on disease severity scores and a predefined set of reasons for euthanasia are needed.  相似文献   
18.
为了明确新疆南疆某猪场猪一起疫情发病原因,本研究采用发病情况调查、临床症状检查、病理学剖检、病理组织学观察和RT-PCR方法进行系统分析。结果诊断为该猪场猪感染猪繁殖与呼吸综合征病毒,且初步鉴定为高致病性猪繁殖与呼吸综合征。该诊断结果为该场乃至新疆南疆猪病的诊断和防制提供一定的方法和指导意义。  相似文献   
19.
采用硫酸水解法(aldito-acetate procedure)、X射线粉末衍射(XRD)、傅里叶变换红外光谱(FTIR)分析了蒸爆过程中毛竹材加工剩余物纤维聚集态结构及主要化学成分的变化.研究结果表明,(1)毛竹材加工剩余物经蒸爆处理,60%左右的半纤维素水解,木质素低分子化且裸露到纤维表面,易被80%乙醇及木质素溶剂提取,从而实现毛竹材加工剩余物主要组分的有效分离.(2)毛竹材加工剩余物经蒸爆处理,80%乙醇抽提物得率提高,综纤维素得率减少,木质素含量减少:葡萄糖相对含量增加,半纤维素降解明显.(3)210℃处理10 min和220℃处理10 min的蒸爆浆的化学组成变化几乎没有区别,但两者与200℃处理10 min差别较大,210℃处理10 min是毛竹材加工剩余物适宜的处理温度.(4)FTIR结果显示蒸爆处理后在1040~1060 cm-1区的吸收峰分裂为明显的2个峰表明半纤维素降解,1166 cm-1处的吸收强度明显减弱,表明C-O-C键有不同程度的断裂.X-身寸线衍射分析结果显示毛竹材加工剩余物蒸爆处理后纤维素相对结晶度增加.  相似文献   
20.
黄杨属植物ITS序列分子进化特点分析   总被引:1,自引:0,他引:1  
黄杨属植物种类多,分类较为混乱,特别是中国特有种珍珠黄杨的分类地位和系统进化存有争议,鉴于此,本文选取黄杨属5种植物和珍稀濒危植物珍珠黄杨的5个居群,对其rDNA ITS序列分析,结合GenBank中报道的黄杨属其它9个种,以板凳果属顶花板凳果的ITS序列为参照,用成对比较的方法对黄杨属18种植物的ITS序列比较发现,...  相似文献   
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