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1.
The male of Brumptomyia angelae, sp. nov., a new species of Phlebotominae (Diptera, Psychodidae) of the Atlantic forest of the state of Paraná, Brazil, is described and illustrated. This new taxon is closely related to Brumptomyia ortizi Martins, Silva & Falc?o 1971, Brumptomyia nitzulescui (Costa Lima, 1932), and Brumptomyia troglodytes (Lutz, 1922). The male genitalia of these three latter species have also been drawn.  相似文献   

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Antiserum raised against the β-subunit of wheat (Triticum aestivum) chloroplast ATPase cross-reacts with a 51000 protein located in the membrane fraction of Escherichia coli. The differential solubility of this polypeptide after chloroform treatment of unc+ and uncD409 strains indicates that this cross-reacting polypeptide is the bacterial β-subunit of ATPase. Thus a high degree of conservation of antigenic determinant sites exists between a bacterial β-subunit and the β-subunit of a monocot. This conservation also seems to extend to the β-subunit of mitochondrial ATPase of yeast (Saccharomyces cerevisiae).  相似文献   

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Population density (number of propagules/l) of Pythium in the irrigation water has been studied in the reservoirs of the Poniente Almeriense (Almería, Spain). These reservoirs are habitually used in the watering of the greenhouse crops of the district. From October 1994 to August 1997, 17 sampling campaigns were carried out, 23 reservoirs were visited and three of them were sampled during three years. 300 ml of superficial water were sampled and analyzed in the laboratory by means of filtration with paper Whatman number 1, placed on Ponchet selective medium and incubated at 20 degrees C. Data of the physical-chemical characteristics of the water (temperature, pH, CE, anions and cations) were taken. The geographical and seasonal distributions of the population were correlated with the analyzed characteristics. The more frequent densities were among 0-100 propagules/l. A population's seasonality was observed, with a maximum in winter and a minimum in summer. When Cl- concentration was higher, the number of propagules/l was smaller.  相似文献   

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Summary Corynebacterium fascians causes a fasciation disease in a number of dicotyledons and this disease appears to be caused by compounds with cytokinin activity elaborated by the infecting bacteria. Extractions of C. fascians in late logarithmic phase under conditions where the pH never falls below 7.0 yield about 2 g/l of N 6-(2, a potent cytokinin. If a mild acidification step is included in the extraction procedure the yield increases to about 12 g/l. This is due to release of N 6-(2-isopentenyl)adenine from C. fascians tRNA during the extraction procedure. In terms of total cytokinin activity present in C. fascians cultures, N 6-(2-isopentenyl)adenine appears to be a minor component.  相似文献   

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Abstract

Two metabolites of a free radical scavenger, edaravone, were synthesized. Edaravone glucuronate was synthesized by glycosylation of a glucuronic acid precursor using silver (I) trifluoromethane-sulfonate with edaravone. Edaravone sulfate was synthesized by sulfonylation of edaravone using a sulfur trioxide-pyridine complex. The two synthesized metabolites were identical to isolated metabolites. X-ray analysis identified edaravone glucuronate as β-O-glucuronate, although there were three possible edaravone glucuronate tautomers.  相似文献   

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Adult snails synthesize in their albumen glands a storage polysaccharide called galactan which is utilized by the developing embryos. With [6-3H]-uridine 5diphosphogalactose the incorporation of labelled d-galactose into the polysaccharide can be traeed in freshly removed glands maintained in a bathing buffer. After centrifugation of homogenized glands, galactosyltrasferase activity is only found in the insoluble fraction. Chaps extracts of this material retain almost all of their activity and can be used for comparison of the incorporation rates into different native galactans or in various oligosaccharides. A highly efficient -(16) galactosyltransferase was detected when methyl 3-O-(-d-galactopyranosyl)--d-galactopyranoside was offered as acceptor. The substitution at the penultimate residue resulted in a branched trisaccharide as demonstrated by 1H-NMR-spectroscopy and permethylation analysis of the reaction product. Comparable results were obtained with various oligosaccharides containing an internal galactose unit glycosidically linked 13. Attempts to separate and purify the various enzymes involved resulted in the isolation of a fraction which is able to transfer d-Gal exclusively to native galactan, but not to oligosaccharides. A further fraction was obtained from a different resin with activity for native galactan and 6-O-(-d-galactopyranosyl)-d-galactopyranose. but without any for methyl-3-O-(-d-galactopyranosyl)--d-galactopyranose. It is thus concluded that at least three different enzymes are involved in the biosynthesis of this snail galactan.Abbreviation Gal galactose - glc gas-liquid chromatography - Gro glycerol - tlc thin layer chromatography  相似文献   

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Brian V. Timms 《Hydrobiologia》2001,466(1-3):245-254
Lake Wyara receives most of its water from Werewilka Creek, with the area between the two forming Werewilka Inlet which is highly variable in area, and salinity and has high habitat heterogeneity. Over 12 years, 84 species of macroinvertebrate were found in the inlet, but only 34 in the lake. Halobiont and halophilic species were the same in each, but there were many fewer salt-tolerant species in the lake and no freshwater species. The latter were excluded by salinity, but habitat homogeneity due to strong wave action in the lake seems to limit many salt-tolerant species to the inlet. Species richness in large saline lakes in inland Australia is limited by salinity, poor speciation opportunities engendered by their episodic nature, and habitat homogeneity.  相似文献   

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Abstract

The preparation of a base-labile (Dnpe) protected derivative of 6-mercaptohexanol is described. The use of the phosphoramidite derivative of this compound improves both yields and the time needed for the preparation of oligonucleotides containing a thiol group at the 5′-end.  相似文献   

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In this paper, we study a sample of cranial, mandibular and dental remains of two species of the machairodontine felid genus Machairodus from the Early Vallesian (MN 9, around 10 Ma) site of Los Valles de Fuentidueña (Segovia, Spain): the tiger-sized Machairodus aphanistus, and the smaller and more primitive M. alberdiae; a species which is only known from this site. The fossils of these two sympatric populations are compared with the most abundant samples of M. aphanistus from the Late Vallesian (MN 10), younger sites of Batallones-1 and Batallones-3 (Torrejón de Velasco, Madrid, Spain). The results support the specific separation of M. alberdiae from M. aphanistus based on several differences in teeth size and proportions. Besides this, we observed differences among the analysed samples of M. aphanistus, indicating a differentiation between the older and more primitive form from Los Valles de Fuentidueña, and the younger and more derived one from the two Batallones sites. These differences fit well with the morphological evolution of this lineage towards the more derived Turolian Amphimachairodus giganteus. Finally, a relatively structured, patched habitat, combining the presence of open landscapes with shrubby and wooded areas, is inferred to explain the sympatric distribution of these two large machairodontines in Los Valles de Fuentidueña.  相似文献   

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Although still in relatively good condition, the Gala´pagos Archipelago suffers from increasing human pressures. Apart from direct actions like hunting and logging, endemic plants and animals are threatened by introduced species, and in many cases the present status of the populations is not known. The conservation status of eight plant species considered endangered was studied from literature and field surveys and the main threats were determined. Each of the eight species is endemic to only one island but in some cases is also present on nearby islets. Of these eight species, one is considered extinct, one critically endangered, and the others suffer various levels of threat. As in all island systems of the world, the main threats are introduced organisms, both plants and animals. The extinct species probably disappeared owing to invasion by Lantana camara, one of the most aggressively invasive plants of the islands, and the most endangered species is threatened by goats. The remaining species seem to be regenerating well and we can expect positive results from protection efforts. Today, only one of the eight species benefits from a direct protection action.  相似文献   

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Based on a complex approach including morphological and molecular genetic methods, the taxonomic position of two casebearer moth species Coleophora tsherkesi Falkovitsh, 1970 and C. isabellina Falkovitsh, 1970 (Lepidoptera, Coleophoridae) is discussed. On the phylogenetic tree based on the cytochrome oxidase subunit I gene (COI), two species form a common cluster with species of the genera Ionescumia, Carpochena, and Goniodoma. Data on the molecular phylogeny and morphology justify the placement of Coleophora tsherkesi and C. isabellina in a separate genus Falkmisa Anikin et Dyomin, gen. n. Thus, the tribe Carpochenini includes three genera: Ionescumia, Carpochena, and Falkmisa.  相似文献   

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Q Zhan  X Wang 《ZooKeys》2012,(204):41-46
A new species of Bankisus Navás, 1912,(Bankisus sparsussp. n.)is described and illustrated with the genus newly recorded from China. A key to species of Bankisus is provided.  相似文献   

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Sorbitol, xylitol, erythritol and lactitol were used as the acceptors of galactosyl radicals, in the process of transgalactosylation accompanying the hydrolysis of lactose, conducted with -galactosidase (4.0 ml Lactozym 3000 was added to 430 ml 1.45 M lactose with 0.95 M polyhydroxyalcohols). The following concentrations of galactosyl derivatives of polyols were obtained after hydrolysis for 4 h at 40°C: 0.31 M Gal-erythritol, 0.22 M Gal-xylitol, 0.18 M Gal-sorbitol and 0.14 M Gal-lactitol. A quadruple increase of xylitol content in dry matter of a solution (from 11.5% (w/w) to 44.5% (w/w) brought about a 2.3-fold increase of the product content in the solution (15.2% (w/w) of dry matter).  相似文献   

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A kinetic analysis has been made of the interaction of α-Hb chains with a mutant α-hemoglobin stabilizing protein, AHSPV56G, which is the first case of an AHSP mutation associated with clinical symptoms of mild thalassemia syndrome. The chaperone AHSP is thought to protect nascent α chains until final binding to the partner β-Hb. Rather than protecting α chains, the mutant chaperone is partially unfolded but recovers its secondary structure via interaction with α-Hb. For both AHSPWT and AHSPV56G, the binding to α-Hb is quite rapid relative to the α-β reaction, as expected because the chaperone binding must be quite competitive to complete the α chain folding process before α-Hb binds irreversibly to β-Hb. The main kinetic difference is a dissociation rate of AHSPV56G·α-Hb some four times faster relative to AHSP·α-Hb. Considering a role of protein folding, the AHSPV56G apparently does not bind long enough (0.5 s versus 2 s for the WT) to complete the structural modifications. The overall replacement reaction (AHSP·α-Hb + β-Hb → AHSP + αβ) can be quite long, especially if there is an excess of AHSP relative to β-Hb monomers.  相似文献   

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