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Trichophyton erinacei is a fungus affecting hedgehogs. As these animals have become popular as exotic pets, human infections with this organism have been documented in many countries. In Taiwan, a 36-year-old woman developed tinea lesions at multiple sites after carrying a sick hedgehog. The animal subsequently lost its quills and died. On culture of the patient’s skin scrapings, the pathogen was identified mycologically as Trichophyton erinacei, which was confirmed by sequencing of the internal transcribed spacers of the fungal nuclear ribosomal DNA. The same fungus was isolated from the sawdust bed previously used by the diseased hedgehog. A careful contact history is important for identifying this emerging zoonosis.  相似文献   

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Two Upper Paleocene and one Lower Eocene localities from Morocco (Ouarzazate basin) have yielded terrestrial assemblages that stand among the rare herpetofaunas from the Paleogene of the African Plate. The collections include one of the rare frogs and the only lizards known from the Paleogene of Africa. One of the two Upper Paleocene localities, Adrar Mgorn 1, has produced an indeterminate anuran and the most diverse assemblage of squamates from the Mesozoic and Cenozoic of Africa. It has yielded the earliest known scolecophidian snake and the earliest Gekkonidae, amphisbaenians, Tropidophiidae, and perhaps Boidae from Africa. Moreover, a specimen represents either the last sphenodontian or the earliest acrodontan lizard from this continent. One of the amphisbaenians represents a very distinct new taxon, Todrasaurus gheerbranti gen. and sp. nov. Indeterminate scincomorphans, lacertilians, Madtsoidae, and Aniliidae are also present. The fauna from the Lower Eocene is less diverse than that from the Upper Paleocene, but some taxa are common to both levels. Contrary to nearly all other Paleogene herpetofaunas from the African Plate, these Paleocene and Eocene assemblages include taxa that were terrestrial, not aquatic.  相似文献   

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Ten gene loci of nine enzyme systems (PGI, 6-PGD, NADHD, SKDH, GDH, PGM, DIA, ADH, GOT-1, and GOT-2) were analyzed in Cypripedium calceolus, C. macranthon, C. shanxiense, and C. × ventricosum plants from the south of the Russian Far East. Alleles of loci 6-PGD, NADHD, GDH, ADH, GOT-1, and PGI proved to be diagnostic for C. calceolus and C. macranthon. Plants of C. shanxiense from Primorye and Sakhalin Island were monomorphic at all of the loci examined, and their allelic structure can be regarded as diagnostic for the species. The allelic structure for fragments of the C. calceolus population from the western and eastern parts of the species range differed in two loci, PGI and SKDH: alleles absent in C. calceolus plants from the western part of the range occurred at a high frequency in the plants of this species from the eastern part of the range (28–41% and 55–68%, respectively). These alleles were found in C. shanxiense. The genetic structure of C. shanxiense was similar to that of C. calceolus from the eastern part of the range, i.e., the region when these species are sympartic. The additional alleles in C. calceolus from the eastern part of the range might have appeared as a result of hybridization with C. shanxiense. Our results indicate that C. calceolus plants occuring on the territory of Russia form two groups that represent two different units of genetic diversity preservation. We suggest that C. × ventricosum plants in southern Primorye were formed by hybridization between C. macranthon and C. calceolus × C. shanxiense hybrids. Thus, they differ from plants inhabiting the Urals and West Siberia, which originated by hybridization between C. macranthon and C. calceolus. The population of C. × ventricosum presumably also consists of two plant groups differing in genetic structure, which should be regarded as two different units of preservation of this taxon.  相似文献   

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ATMOSPHERIC oxygen is not in equilibrium with sea water with respect to the isotope exchange illustration but has an 18O excess of about 22‰ compared to sea water1. This could be due to isotope fractionation during respiration2. Another large contribution to the effect has been overlooked up to now. Photosynthesis on land takes place in transpiring leaves, where the difference in the vapour pressure of 16OH2 and 18OH2 concentrates the heavy molecules in their stationary water content. Since the free oxygen stems from the water in which photosynthesis takes place3–8 (with only a very small shift in isotopic composition9), photosynthesis on land is an 18O source for atmospheric O2. We have begun to study this effect quantitatively.
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A well-organized protocol has been developed for high frequency root germination from the seed of Canavalia ensiformis on Murashige and Skoog (MS) medium. Surprisingly, the seeds that were grown on the MS medium having no growth hormone showed the best response. Roots of 30 days old aseptic seedling were homogenized and a lectin from them was purified on Sephadex G-50 affinity column. The finding that final product is a pure lectin was confirmed by specific hemagglutinating property. The final root lectin yield was 0.6% and eluted as a single peak. Root lectin specific activity was 50 times more than the seed lectin. Sugar specificity activity by hemagglutination-inhibition assay indicated that lectin belongs to glucose/mannose-specific group. Interestingly, the lectin was found to be 25 kDa, similar to molecular mass of Concanavalin A purified from seed of C. ensiformis, as revealed by SDS–PAGE. Thus, Concanavalin A from either source can be used for development of transgenic crops that are capable of expressing lectin gene and hence can efficiently perform biological nitrogen fixation by giving rise to nodules in their root. The advantage of this method is that purification of Concanavalin A in tissue culture conditions is easier, handy and is less time consuming.  相似文献   

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