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91.
This study concerns the evaluation of micromorphological and anatomical characters of fruit (achene-cypsela) in 12 Turkish endemic Tripleurospermum taxa using multivariate analyses (cluster analysis, principal component analysis, one-way analysis of variance). Pericarp in all taxa examined is mainly composed of several layers of parenchymatous and sclerenchymatous cells with one vascular bundle in each rib. In the achene, the thickness and width of lateral and adaxial ribs with presence or absence of a slime envelope have high taxonomic value for Tripleurospermum at interspecific levels. The slime envelope formation is also correlated with ploidy levels and habitats of some taxa in Tripleurospermum.  相似文献   
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Sulfite is a potentially toxic molecule that might enter the body via ingestion, inhalation, or injection. For cellular detoxification, mammalians rely on sulfite oxidase to convert sulfite to sulfate. The purpose of this research was to determine the effect of sulfite on zinc, iron, and copper levels in rat liver and kidney tissues. Forty normal and sulfite oxidase-deficient male albino rats were divided into four groups that included untreated controls (group C), a sulfite-supplemented group that received 70 mg sodium metabisulfite per kilogram per day (group S), a sulfite oxidase-deficient group (group D), and a sulfite oxidase-deficient group that was also given 70 mg sodium metabisulfite per kilogram per day (group DS). The iron and zinc levels in the liver and kidney in groups S and DS were not affected by sulfite treatment compared to their respective controls (groups C and D). Sulfite exposure led to an increase of kidney copper content in the S group when compared to untreated controls. The kidney copper levels were significantly increased in the unexposed deficient rats, but it was not different than that of the deficient rats that were given oral sulfite treatment. These results suggest that kidney copper levels might be affected by exogenous or endogenous sulfite. An erratum to this article is available at .  相似文献   
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In this study, 121 wild edible plants used as food in Anatolia were surveyed to determine the plant parts used and their detailed preparation methods. The results of this study show that the plants may be boiled, fried in fat, and eaten raw or as rolled vegetables. They may also be consumed as pickles, fruits, sweets and spices, and drunk as cold and hot drinks. Thirty species (8 genera) were identified as belonging to the Lamiaceae family, 15 species (15 genera) belong to the Asteraceae family, 13 species (5 genera) belong to the Rosaceae family, 8 species (7 genera) belong to the Brassicaceae family, 6 species (3 genera) belong to the Orchidaceae family and 5 species (5 genera) belong to the Apiaceae family. The genera represented by the highest number of species in the study are as follows:Sideritis L. is represented by 13 species, Origanum L. by 7 species,Rubus L. by 5 species,Thymus L. by 4 species andRumex L. by 4 species.  相似文献   
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A noticeable effect of sulfite treatment was observed on the plasma ceruloplasmin ferroxidase activity of rats with normal sulfite oxidase activity when compared to normal controls. The plasma levels of selenium, iron, and zinc were unaffected by sulfite in normal and sulfite oxidase (SOX)-deficient rats. While plasma level of Mn was decreasing, plasma Cu level increased in SOX-deficient rats. Treating SOX-deficient groups with sulfite did not alter plasma level of Mn but made plasma level of Cu back to its normal level. This is the first evidence that Cu and Mn status were affected in experimental sulfite oxidase deficiency induced by low molybdenum diet with tungsten addition deserving further research to determine the underlying mechanisms of these observations in experimental sulfite oxidase deficiency.  相似文献   
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Electronic absorption and 8.0 T magnetic circular dichroism (MCD) spectra are reported for M(CN)8 4−, M=Mo(IV) and W(IV), in aqueous solution and M(CN)8 3−, M=Mo(V) and W(V), in acetonitrile solutions. In addition some absorption and MCD spectra are reported for the M(CN)8 3− ions embedded in thin poly methyl methacrylate (PMMA) plastic films at temperatures from 295 to 10 K. The temperature dependence of the MCD spectra confirms the presence of C terms. The solution and PMMA spectra for the both Mo and W complexes in either the IV or V oxidation states are remarkably similar to each other for the same oxidation state and are interpreted within a D2d structural framework for the isotropic environment. The weak bands below 3.0 μm−1 (1 μm−1=104 cm−1) for the M(IV) complexes are assigned as metal-localized ligand field (LF) transitions. LF transitions are also suggested for weaker unresolved absorption between 3.0 and 3.6 μm−1 for the M(V) ions. The intense bands above 3.6 μm−1 for M(IV) and 4.6 μm−1 for M(V) complexes are interpreted as metal to ligand charge transfer (MLCT) from the metal b1(x2y2) HOMO to CN-based π * orbitals. The prominent intense bands observed below 4.5 μm−1for the M(V) complexes are assigned as ligand to metal charge transfer (LMCT) from occupied non-bonding or weakly π bonding CN orbitals to the half-filled b1(x2y2) HOMO.  相似文献   
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We describe an optimized system for the easy, effective, and precise modification of the Escherichia coli genome. Genome changes are introduced first through the integration of a 1.3 kbp Landing Pad consisting of a gene conferring resistance to tetracycline (tetA) or the ability to metabolize the sugar galactose (galK). The Landing Pad is then excised as a result of double-strand breaks by the homing endonuclease I-SceI, and replaced with DNA fragments bearing the desired change via λ-Red mediated homologous recombination. Repair of the double strand breaks and counterselection against the Landing Pad (using NiCl2 for tetA or 2-deoxy-galactose for galK) allows the isolation of modified bacteria without the use of additional antibiotic selection. We demonstrate the power of this method to make a variety of genome modifications: the exact integration, without any extraneous sequence, of the lac operon (~6.5 kbp) to any desired location in the genome and without the integration of antibiotic markers; the scarless deletion of ribosomal rrn operons (~6 kbp) through either intrachromosomal or oligonucleotide recombination; and the in situ fusion of native genes to fluorescent reporter genes without additional perturbation.  相似文献   
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