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The American brackish-water mussel Mytella strigata is reported from Singapore for the first time. In 2016 a survey of intertidal hard structures in the Johor Straits revealed its almost ubiquitous presence in high mean densities, up to 124?±?32 individuals 25?cm?2 along the shoreline. Subtidal nets employed by floating fish farms were also fouled with this species. Densities exceeding 10,000 individuals 100?cm?2 were observed, to the exclusion of its relative Perna viridis, the Asian green mussel. Size-frequency analyses of shells indicated the presence of both juveniles and adults. Juveniles have an extremely variable shell surface pigmentation. The adults, reaching 5?cm in shell length, generally have a thick dark greenish brown to almost black periostracum, but bright green and olive green individuals, some with distinctive brown streaks, have also been observed. However, sequences of the mitochondrial COI gene were consistent with mussels from Brazil, Colombia and Ecuador, where they are natively distributed, while shells were reconcilable with type material. The species may have been transported in ballast water and/or with fouling directly from its native provinces, or spread from the Philippines where there are already established populations of M. strigata, possibly since the nineteenth century. 相似文献
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The idea that the mechanism of the very low energy fluxional behaviour of [Fe3(CO)12] may be based on the movement of the ligand icosahedron about the central Fe3 triangle which corresponds to a rotational symmetry operation of the CO ligand icosahedron is discussed and rejected. 相似文献
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An eight-years-old girl, who presented with recurrent upper respiratory tract infections, was treated with broad-spectrum antibiotics. Afterward she presented with intestinal candidiasis. The isolated species was identified as Candida albicans by differential tests. Treatment given was with 500,000 IU of oral nystatin every 8 hours for 10 days and intestinal normal microbiota restoratives. Evolution has been satisfactory, although concomitantly type A hepatitis developed. Rest and a soft diet were recommended. The child is now perfectly healthy with normal liver function tests. Conclusion: Prolonged treatments with broad-spectrum antibiotics destroyed the indigenous intestinal microbiota, which provoked intestinal C. Albicans proliferation and adversely affected the immunological system of the patient, thus facilitating the establishment of a viral infection.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
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Ralstonia sp. strain PBA was isolated from textile wastewater in a coculture with Hydrogenophaga sp. strain PBC. Here we present the assembly and annotation of its genome, which may provide further insights into the mechanism of its interaction with strain PBC during 4-aminobenzenesulfonate degradation. 相似文献