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331.
SHISuhua DUYaqing D.E.Boufford GONGXun HUANGYelin HEHanghang ZHONGYang 《科学通报(英文版)》2003,48(15):1576-1580
The chloroplast gene matK and the internal transcribed spacers (ITS) of the nuclear ribosomal DNA from Schnabelia, a genus endemic to China, and 6 genera of Verbenaceae and 13 genera of Lamiaceae were sequenced. The phylogenetic signal and validity outgroups were measured and evaluated by means of the relatively apparent synapomorphy analysis (RASA). Independent and combined phylogenetic analyses for the matK and ITS sequences were performed using the maximum parsimony (MP), neighbor-joining (NJ) and maximum likelihood (ML) methods, indicating that Schnabelia oligophylla and Caryopteris terniflora form a sister-group relationship. The Caryopteris complex is not shown to be a monophyly because Trichostema, C. paniculata and C. forrestii are paraphyletic to the clade containing the remaining members of the complex. A monophyly of Ajugoideae proposed by Cantino et al., including 8 genera in this study, is strongly supported and the closest relatives of Schnabelia are in the Ajugoideae (Lamiaceae), especially near Caryopteris terniflora. The polygenetic analyses also showed that the genera of Lamiaceae and Verbenaceae sampled in this tudy are phylogenetically mixed and the genus Avicennia is distant to other genera of Verbenaceae. RASA and combined analysis can be used as effective approaches to determining the relationships among phylogenetically complex groups. 相似文献
332.
GAO Lin WANG Dongyan LI Yang BU Dingfang CHANG Lin PANG Yongzheng QI Yongfen & TANG Chaoshu . Institute of Cardiovascular Disease Research Peking University First Hospital Beijing China . Department of Physiology Peking University Health Science Center Beijing China 《科学通报(英文版)》2003,48(10):983-987
Homocysteine (Hcy), a highly reactive sulfur- containing amino acid, is an intermediate product of methionine metabolism. Elevation of plasma Hcy has been widely studied as an independent risk factor for many cardiovascular diseases such as atherosclerosis, thrombosis, etc.[1]. Inherited hyperhomocysteinemia cases usually suffer from occlusion or thrombosis in arteries and large veins before the age of 20. Hyperhomocysteinemia significantly reduces the survival rate[2] and dilatation functi… 相似文献
333.
Difference in metapopulation structure and dynamics of two species of coexistent melitaeine butterflies 总被引:3,自引:0,他引:3
WANG Yifei CHEN Jiejun WANG Rongjiang LEI Guangchun & XU Rumei . Ministry of Education Key Laboratory for Biodiversity Science Ecological Engineering Beijing Normal University Beijing China . College of Life Sciences Peking University Beijing China Correspondence should be addressed to Xu Rumei 《科学通报(英文版)》2003,48(12):1239-1246
Habitat fragmentation has been considered to be the most important cause of the extinction and the loss of bio-diversity[1,2]. With the increase of human activities in re-cent years, natural habitat decreased rapidly and patches became smaller and more isolated[3,4]. This leads to an obvious change of population structure and dynamics of many species. However, some species may persist as metapopulations in seriously fragmented landscapes[5]. Metapopulation theory and methodology is estab-lish… 相似文献
334.
GU Zhaoyan LIU Qiang XU Bing HAN Jiamao YANG Shiling DING Zhongli & LIU Tungsheng Institute of Geology Geophysics Chinese Academy of Sciences Beijing China Correspondence should be addressed to Gu Zhaoyan 《科学通报(英文版)》2003,48(12):1271-1276
Two modes of photosynthesis predominate in terres-REPORTS trial plants: the C3 and C4 modes[1]. The C3 mode is used by all of trees, bushes, and cold season grasses. The C4 mode is used by the most of tropical and warm season grasses. They are disadvantaged relative to C3 plants at high CO2/O2 ratios because of the additional energy ex-pense needed to concentrate CO2 in the bundle-sheath cells. At low CO2/O2, however, C4 plants can achieve a relatively high quantum yield by suppressin… 相似文献
335.
Geochronology of source materials from high-pressure and ultrahigh-pressure metamorphic rocks in Jurassic sedimentary rocks of Hefei Basin 总被引:4,自引:0,他引:4
LI Renwei SANG Haiqing ZHANG Renhu CHU Zhuyin LI Shuangyin JIN Fuquan & JIANG Maosheng . Institute of Geology Geophysics Chinese Academy of Sciences Beijing China . Department of Resource Environment Sciences Hefei Industrial University Hefei China 《科学通报(英文版)》2003,48(6):605-610
Eclogite cobbles were discovered by Wang et al. (2001) in the Fenghuangtai Formation of the northern margin of Dabie Mountains in the Dushan area of Anhui Province, China[1]. They proposed that after the formation during the Triassic, the high-pressure (HP) and ultra-high-pressure (UHP) metamorphic rocks reached the sur-face through exhumation and uplifting before the late Ju-rassic. However, they have not provided any evidence about isotopic ages. One kind of cobbles of HP-UHP rocks w… 相似文献
336.
GEChendong O.Slaymaker T.F.Pedersen 《科学通报(英文版)》2003,48(21):2357-2361
Pb geochronology and sediment core profiles of organic carbon, total sulfur and organic carbon isotope (d 13C) values were used to reconstruct the local environ-mental history of the Shamei Lagoon, located in the Wan-quan River Estuary, eastern Hainan Island, China. Totalsulfur and d 13C values decreased upwards in the top 30 cm of a sediment core that spanned the last 200 years of deposi-tion. Total sulfur concentration and d 13C values respectively decreased upward from 1.92% to 0.36%, and -20.63?to -23.64? The C/S ratio in the 19th century and earlier was relatively stable in the range of 0.47—0.80, and there was a positive correlation between organic carbon and total sulfur. Since around 1900 AD, the C/S ratio increased rapidly to a maximum of 3.94, but no simple correlation was found be-tween organic carbon and total sulfur during this more re-cent period. These results indicated that before 1800 AD, the lagoon had a fully marine character, and the location of to-day抯 Wanquan River Estuary was an open embayment.From 1800 to 1900, the salinity of Shamei Lagoon decreased noticeably. The amount of seawater which could enter thelagoon decreased gradually as the Yudai spit grew. Today,seawater scarcely affects the lagoon; it is essentially a fresh-water basin. 相似文献
337.
Thermodynamic evolution of lithosphere of the North China craton: Records from lower crust and upper mantle xenoliths from Hannuoba 总被引:1,自引:0,他引:1
LIU Yongsheng * GAO Shan LIU Xiaoming CHEN Xiaoming ZHANG Wenlan & WANG Xuance . Faculty of Earth Sciences China University of Geosciences Wuhan China . The State Key Lab for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing China . Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi抋n China Correspondence should be addressed to Liu Yongsheng 《科学通报(英文版)》2003,48(21):2371-2377
Lithospheric thinning in East China attracts much attention of geologists. In many cases where a lithospheric thinning is inferred, the trigger for instability is a preced-ing episode of crustal thickening by the continental colli-sion[1]. Lithospheric processes (e.g. lithospheric thinning) could be recorded by the thermal history of the lower crustal and upper mantle xenoliths. Xu et al.[2] suggested that the cooling (from >1200 to 850℃) recorded by spinel harzburgite from Northeast China … 相似文献
338.
WANG Weiming LIU Jinling & ZHOU Xiaodan . Nanjing Institute of Geology Palaeontology Chinese Academy of Sciences Nanjing China . Nanjing Geological Museum Nanjing China Correspondence should be addressed to Wang Weiming 《科学通报(英文版)》2003,48(18):2005-2009
Many related papers have been published since the first report on the discovery of Nanjing hominid crania by Mu et al.[1]. Mu et al.[1], Xu et al.[2—4], the Tangshan Ar-chaeological Team[5] and Dong[6] have successively stud-ied the Nanjing Homo erectus?symbiotic faunas. Mu et al. and Xu et al. considered that the nature of the fauna in the Tangshan area belongs to the Oriental Realm,and this region was usually occupied by Ailuropoda-Tapirus fauna in the Pleistocene. However, the typica… 相似文献
339.
J. J. Benattar 《科学通报(英文版)》2003,48(17):1800-1802
When the thickness of soap foam film varies in adefinite region, color changes of a soap bubble will be observed due to the interference of light. Black soap films are the final stages of thinning of soap films due to the drainage of water in the absence of evaporation and are generally formed from solutions of an ionic surfactant in the presence of salt. After a bubble is formed, in the beginning the soap film is relatively thick and it appearswhite; then the film thins gradually and finally … 相似文献
340.
FENG Mingguang & LIANG Yong . Institute of Microbiology College of Life Sciences Zhejiang Univer-sity Hangzhou China . Institute of Applied Entomology College of Agricultural Sciences Biotechnology Zhejiang University Hangzhou China 《科学通报(英文版)》2003,48(17):1816-1821
Among entomopathogenic fungi the Entomophthor- ales plays an important role in natural control of insect pests through induction of epizootics in insect popula-tions[1—3]. Since most species of the fungal group are 4 - characteristic with their special capability of actively dis-charging conidia to favor infection and dissemination in host populations, they are ideal targets for epizootiologi-cal study, being considered as important microbial control agents. Currently, 66 species … 相似文献