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841.
KANG  Tau  Tae Hwa  Jin III  KIM 《Entomological Research》2002,32(1):21-23
ABSTRACT We examined newly recorded species, Pseudoabsidia ussurica Wittmer, from Korea. The species was redescribed with their color variation. Also, the photos of adult habitus and aedeagus are provided.  相似文献   
842.
1975年和1987年分别在湖南宜章和云南景东采到角蟾属Megophrys标本2种。经与角蟾属已知种对比,特别是与相近种白颌大角蟾M.lateralis(Anderson)在外部形态和头骨特征方面的深入研究,其差异明显,被确定为2新种,即莽山角螗M.mangshanensis和腺角蟾M.glandulosa。本文对2新种的形态和生态资料作了记述。  相似文献   
843.
浙江及其邻近地区的紫堇属植物   总被引:7,自引:0,他引:7  
浙江及其邻近地区有紫堇属(Corydalis Vent.)植物18种、5变种和1变型。本文各并了2变种,订正了1种的名称,发表2个新变种——全叶土元胡和浙江黄堇,并提升1个变种——无距小花黄堇。讨论了小花黄堇、全叶延胡索和台湾黄堇的某些问题。文中附名录和分布表及种子扫描电镜照片10张。  相似文献   
844.
Luminous bacteria isolated from the light organs of the Australian Pinecone fish Cleidopus gloriamaris have been studied. The isolates were from fish from four different geographical estuarine systems on the east coast of Australia. All isolates were found to be strains of Vibrio fischeri, a species not hitherto demonstrated conclusively as forming a symbiotic association. Some ecological considerations are discussed.Non-Standard Abbreviation PHB polyhydroxybutyrate  相似文献   
845.
The formate dehydrogenases of Clostridium acidiurici and of C. cylindrosporum coupled the oxidation of formate with the reduction of viologen dyes. The basal activity level was about 0.85 moles/min s mg of protein for both species. The level of formate dehydrogenase of C. acidiurici increased 12-fold when 10-7 M tungstate and selenite were present during growth. Molybdate exerted no effect. On the other hand, molybdate and selenite were required to increase the formate dehydrogenase of C. cylindrosporum, and tungstate exhibited an antagonistic effect in this organism.Growth on hypoxanthine generally depended on the addition of bicarbonate. Supplementation with tungstate and selenite accelerated growth of C. acidiurici and increased again the level of formate dehydrogenase. The addition of both, molybdate and selenite was necessary to initiate growth of C. cylindrosporum and to form an active formate dehydrogenase.The differences in the requirement for metal ion supplementation to form high levels of formate dehydrogenase and their involvement in hypoxanthine degradation can be used to differentiate between C. acidiurici and C. cylindrosporum.Abbreviation FDH formate dehydrogenase  相似文献   
846.
A new mesophilic, monotrichously flagellated methane-producing coccus of 1m in diameter was isolated from an anaerobic sour whey digester, originally inoculated with sewage sludge. Growth and methane production were observed with H2/CO2, formate and — less effectively — with 2-propanol/CO2. The isolate grew at temperatures between 15° C and 45° C with the optimum at around 37° C. Acetate, yeast extract and tungstate were required in the medium. Clarified rumen fluid stimulated growth.The DNA of the new methanogen has a G+C content of 48.5 mol%. Comparative 16 S rRNA oligonucleotide cataloguing allows to define the new isolate as a member of a new genus of the order Methanomicrobiales. Further evidence for this is provided by the antigenic crossreactivity with anti-S probes and by metabolic features.Because of its small size the new methanogen is named Methanocorpusculum parvum.This work was supported by a grant of the Deutsche Forschungsgemeinschaft DFG to J. W. and E. S. Immunologic studies were supported in part by grants No. DE-FGO2-84 R 13197 from the U.S. Department of Energy, and No. 261.81/82 from the North Atlantic Treaty Organization (NATO)  相似文献   
847.
Genotypic relationships between seven Prochloron samples isolated from different didemnid ascidian hosts collected at the Palau archipelago and Munda (Solomon Islands) and one cyanobacterial (Synechocystis) strain were determined by DNA-DNA reassociations. Thermal stability values of DNA-DNA hybrids indicate that all Prochloron samples involved are mutually very closely related and only slightly related with the Synechocystis strain. It is concluded that the Prochloron samples tested are representatives of one and the same species.  相似文献   
848.
A flattened discoid flagellate collected from the Seto Inland Sea, Japan, has been examined by light and electron microscopy. This alga agrees well withClisthodiscus luteus Carter. It has two heterodynamic flagella emerging from a furrow on the upward side of the cell that contains six to 13 yellow-green parietal chloroplasts. It does not rotate but smoothly glide while swimming. The cell has a thin periplast lying between the plasmalemma and chloroplasts. Neither lipid bodies nor mucocysts are seen in the periplast. The pyrenoid matrix being free from thylakoids is penetrated by several cytoplasmic canals from various directions. There are no vesicles of periplastidal network in the narrow space between chloroplast envelope and chloroplast ER. The ultrastructural features ofO. luteus are unique, sharing certain characters with the raphidophycean algae but others withPseudopedinella pyriformis, a unique member of the Chrysophyceae.  相似文献   
849.
Hybridization studies between strains of Kluyveromyces marxianus and the remaining species of the genus involving the use of auxotrophic mutants, are reported. K. marxianus was found to be interfertile with K. bulgaricus, K. cicerisporus, K. dobzhanskii, K. drosophilarum, K. fragilis, K. lactis, K. phaseolosporus, K. vanudenii and K. wikenii. Accepting interfertility as criterion for conspecificity, these nine syngamous taxa are relegated to the status of biotypes or physiologic races of a single species K. marxianus.  相似文献   
850.
New taxa ofChrysophyceae from small heleocrene and limnocrene springs are described and pictured. The delicate flagellates were observed and drawn in living stage immediately after collection. Some of them show peculiar morphology and striking structure of organelles. The following new taxa are described in this paper:Chromulina nasuta, Chromulina pavlikii, Chromulina taeniata, Chromulina oligochrysis, Chromulina pyrenoidosa, Monochrysis stigmatica, Ochromonas oligochrysis, Ochromonas taeniata, Pseudokephyrion hypermaculatum, Pseudokephyrion hyalinum var.tubiforme, Chrysococcus ellipsoideus, Epipyxis borealis var.monoplastida.
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