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Acanthocephalan and spargana parasites were identified within a body wall mass during exploratory surgery in a wild green tree snake. Acanthocephalan parasites have not previously been reported in this species. Surgical excision, the treatment of choice, could not be achieved because of the extensive infiltration of the coelomic cavity.  相似文献   
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Growth and mortality of sibling triploid and diploid Sydney rock oysters, grown at two tidal heights, three stocking densities and three different sites on the Camden Haven River estuary, were compared. Triploids grew faster than diploids. The majority of the growth rate difference occurred after the oysters reached 2 years of age. By 3.2 years, triploids were 49% heavier than diploids. Oysters grown intertidally were larger than those grown subtidally. Oysters stocked at the lightest density of 2 L per basket grew to a significantly larger size than baskets stocked at 3 or 4 L. Growth rates were significantly different at the three sites. Growth was reduced the further the oysters were from the mouth of the estuary. There was no significant difference in mortality between ploidy level, but there were differences between tidal heights, stocking densities and sites. Intertidal oysters suffered higher mortality than subtidal. Oysters stocked at the highest density had a significantly higher mortality than the lowest density; neither of these was significantly different from the medium density. The site closest to the mouth of the estuary had significantly lower mortality than the middle and upper estuary sites.  相似文献   
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Objective To study the efficacy of multiple striate keratotomy for the treatment of persistent corneal erosions suspected to be caused by primary corneal epithelial basement membrane disease.
Design A retrospective study.
Animals 16 dogs, three cats and one Australian dingo.
Procedure A technique called multiple striate keratotomy was used to treat twenty animals suffering from persistent corneal erosions.
Results All persistent corneal erosions healed with only one treatment. Most cases healed within 2 weeks. One case developed a second erosion in the same eye but in a different position to the original erosion.
Conclusions Multiple striate keratotomy is a safe, effective and well tolerated technique for the treatment of persistent corneal erosions thought to be caused by corneal epithelial basement membrane disease.  相似文献   
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Excellent crystals of (TMTSF)(2)AsF(6) (TMTSF, tetramethyltetraselenafulvalene) were employed to obtain x-ray diffraction data for a determination of the electron density distribution in this organic superconductor. Electron density was observed between molecules in a stack of donors of an organic metal and between certain interstack selenium atoms of these donors.  相似文献   
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Femtosecond laser pulses and coherent two-phonon Raman scattering were used to excite KTaO3 into a squeezed state, nearly periodic in time, in which the variance of the atomic displacements dips below the standard quantum limit for half of a cycle. This nonclassical state involves a continuum of transverse acoustic modes that leads to oscillations in the refractive index associated with the frequency of a van Hove singularity in the phonon density of states.  相似文献   
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Angle-resolved photoemission experiments reveal evidence of an energy gap in the normal state excitation spectrum of the cuprate superconductor Bi2Sr2CaCu2O8+delta. This gap exists only in underdoped samples and closes around the doping level at which the superconducting transition temperature Tc is a maximum. The momentum dependence and magnitude of the gap closely resemble those of the dx2-y2 gap observed in the superconducting state. This observation is consistent with results from several other experimental techniques, which also indicate the presence of a gap in the normal state. Some possible theoretical explanations for this effect are reviewed.  相似文献   
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