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991.
本文对云南产的耳蕨属半开羽耳蕨组的12种植物进行了分类学研究,并在组下建立了两个新系,报道了4个新种和一个新组合,修订了该组植物的特征范围。 相似文献
992.
滇西保山地区丁家寨组、卧牛寺组牙形刺的时代 总被引:7,自引:0,他引:7
本首次描述了滇西保山卧牛寺组及永德丁家寨组的Rabeignathus牙形刺动物群,其中2个新种:Rabeignathus yunnanensis sp.nov.,R.ritterianus sp.nov.,并划分出3个牙形刺带,进一步确定了古生物地层工作争论已久的卧牛寺组的时代为Artinskian晚期-Kungurian早期;丁家寨组上段为Sakmarian晚期-Artinskian早期。该牙形刺动物群为暖温型动物群,结合保山地块当时的古地磁资料,丁家寨组、卧牛寺组沉积之时,应处于边缘冈瓦纳区。卧牛寺组玄武岩喷发时间的确定,预示了保山地块从边缘冈瓦纳区分离出来的时间为Artinskian晚期。 相似文献
993.
《Palaeoworld》2016,25(3):444-452
A small tetrapod footprint assemblage from the Anning Formation (Upper Jurassic–Lower Cretaceous) at Konglongshan Town, Yunnan Province, China, contains possible swim traces attributable to theropod dinosaurs based on their tridactyl and mesaxonic pes morphology. Morphotypes are tentatively assigned to the ichnogenera Characichnos and Wintonopus, a third one is similar to Hatcherichnus. Due to the inherent variability observed in tetrapod swim tracks, the names are used here informally describing footprints that reflect a distinct trackmaker behavior rather than anatomically accurate images of the pes anatomy. Variation of the imprint shape is obviously due to extramorphological effects and does not indicate taxonomic diversity of trackmakers. Elongate, slender impressions associated with these tracks are discussed here as possible tail traces. Trackmakers were possibly buoyant and active swimming individuals touching and scratching the bottom of deeper waterbodies with the distal ends of their digits. The orientation of the traces perpendicular to preserved ripples suggest cross-current movement and activities. 相似文献
994.
Data on sleep-related behaviors were collected for a group of central Yunnan black crested gibbons (Nomascus concolor jingdongensis) at Mt. Wuliang, Yunnan, China from March 2005 to April 2006. Members of the group usually formed four sleeping units (adult male and juvenile, adult female with one semi-dependent black infant, adult female with one dependent yellow infant, and subadult male) spread over different sleeping trees. Individuals or units preferred specific areas to sleep; all sleeping sites were situated in primary forest, mostly (77%) between 2,200 and 2,400 m in elevation. They tended to sleep in the tallest and thickest trees with large crowns on steep slopes and near important food patches. Factors influencing sleeping site selection were (1) tree characteristics, (2) accessibility, and (3) easy escape. Few sleeping trees were used repeatedly by the same or other members of the group. The gibbons entered the sleeping trees on average 128 min before sunset and left the sleeping trees on average 33 min after sunrise. The lag between the first and last individual entering the trees was on average 17.8 min. We suggest that sleep-related behaviors are primarily adaptations to minimize the risk of being detected by predators. Sleeping trees may be chosen to make approach and attack difficult for the predator, and to provide an easy escape route in the dark. In response to cold temperatures in a higher habitat, gibbons usually sit and huddle together during the night, and in the cold season they tend to sleep on ferns and/or orchids. 相似文献
995.
996.
以云南普通野生稻为材料,利用抑制差减杂交技术(SSH),构建了白叶枯病菌胁迫的云南普通野生稻特异表达基因的差减文库.通过对文库所有阳性单克隆进行测序,聚类分析后共获得494条高质量的表达序列标签(EST).经过BlastN分析,有417条与已知功能的序列有较高同源性;经BlastX分析,有104条EST与未知功能蛋白或假定蛋白有较高相似性,49条EST未能找到同源匹配,341条EST与已知功能蛋白有较高同源性.初步分析发现,这些基因主要涉及能量代谢、蛋白质代谢、核酸代谢、防御与抗逆应答反应、信号转导、光合作用及膜运输等代谢过程.使用半定量RT-PCR研究了7个可能与白叶枯病抗性相关的EST序列在云南普通野生稻对照和白叶枯病菌处理的叶片中的表达情况,并获得这些基因的表达谱.结果发现,克隆编号为OR7,OR68和OR826的EST受白叶枯病菌胁迫诱导上调表达,其中OR826 EST在蛋白数据库中无同源序列,可能是一类新的白叶枯病抗性基因,而组成型表达的OR143 EST在对照和接菌处理的叶片中均能检测到其mRNA的表达,但其表达量在白叶枯病菌胁迫48 h后逐渐增强,推测这些基因直接参与了云南普通野生稻抗病防御反应.本研究为从云南普通野生稻中发掘和克隆新的白叶枯病抗性基因提供了理论依据,为进一步研究云南普通野生稻抗白叶枯病的分子机制奠定了基础. 相似文献
997.
Feng-Cai Zou Xiu-Tao Sun Yin-Jie Xie Bing Li Guo-Hong Zhao Gang Duan Xing-Quan Zhu 《Parasitology international》2009,58(3):306-307
The seroprevalence of toxoplasmosis in pigs was investigated in Yunnan province, Southwestern China between March 2008 and January 2009. A total of 831 serum samples were collected from 9 counties and assayed for Toxoplasma gondii antibodies by indirect haemagglutination (IHA) test. Antibodies to T. gondii were found in 16.97% (141/831) with slaughter pigs having the highest rate (22.28%), followed by breeding sows (16.59%). The results of the present survey indicated that infection with T. gondii in pigs is widely spread in China, including the Yunnan province, and is of public health concern. 相似文献
998.
云南景谷盆地晚第三纪介形类 总被引:3,自引:1,他引:3
该文首次报道景谷盆地介形类化石13属30种(其中19新种,1未定种)并建立3个介形类化石组合,三号构组以Potamocypris-Candoniella为代表的介形类化石组合,时代为中新世早期;回环组以Herpetocyprella-Metacypris为代表的组合,时代为中新世中晚期;大红猫村组以Leucocythere-Ily-ocypris组合为代表,时代为上新世。 相似文献
999.
该文描述了自云南西北部发现的毛茛科翠雀花属二新种:短葶翠雀花(Delphinium breviscaposum W.T.Wang)和丝苞翠雀花(D.filibracteolum W.T.Wang)。短葶翠雀花与察隅翠雀花(D.chayuense W.T.Wang)在亲缘关系上相近,前者与后者的区别在于短葶翠雀花植株具3条簇生短花葶,总状花序的轴和花梗无毛,小苞片较长,萼片较小,退化雄蕊的瓣片不分裂;丝苞翠雀花与拟长距翠雀花(D.dolichocentroides W.T.Wang)近缘,前者与后者的区别在于丝苞翠雀花的花组成圆锥花序,花梗、萼片和萼距均较短,退化雄蕊的爪无附属物,心皮无毛。 相似文献
1000.