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A nasal, so called ethmoidal, tumor from a fallow deer is described. It appears to be the first reported case of that species. The etiology is discussed.  相似文献   
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The amount and nature of glutathione transferases in rat liver microsomes were determined using immunological techniques. It was shown that cytosolic glutathione transferase subunits A plus C, and B plus L were present at levels of 2.4 ± 0.6 and 1.5 ± 0.1 μg/mg microsomal protein, respectively. These levels are 10-times higher than those for non-specific binding of cytosolic components judging from the distribution of lactate dehydrogenase, a cytosolic marker. The possibility that a portion of these glutathione transferases is functionally localized on the endoplasmic reticulum is discussed. A previously described microsomal glutathione transferase which is distinct from the cytosolic enzymes is present in an amount of 31 ± 6 μg/mg microsomal protein.  相似文献   
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Summary The pineal organ of the sardine, Sardina pilchardus sardina, was investigated light and electron microscopically. The pineal parenchyma contains sensory cells, supporting cells, and ganglion cells, and the overlying tissues appear specialized for light penetration. The ganglion cells are arranged in 3 groups, their axons giving rise to the tractus epiphyseos. The sensory cell is of a photoreceptor type found in several other teleost species. No definitive evidence of a secretion was educed but some indications of an endocrine function are reported and discussed.The pineal receptor cell of neonates of Mugil spp. which have a pigment-free spot above the pineal organ, was investigated electron microscopically and found to have the same organization as that of adult Mugil auratus.Supported by grants from the Helge Ax:son Johnsons Stiftelse, Stockholm, and from the Kungliga Vetenskapsakademien, Stockholm, Sweden. This is gratefully acknowledged.The animal material has been provided by the Stazione Zoologica di Napoli.  相似文献   
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Formalin fixation strongly influences biomechanical properties of the spine   总被引:7,自引:0,他引:7  
As fresh human cadaveric spine specimens for in vitro testing are hard to obtain and carry a potential risk of infection, the possibility of using embalmed spine specimens has been considered. The cross-linking effect of formalin fixation, however, raises uncertainties regarding the biomechanical likeness of preserved specimens. They have been reported to be stiffer, but no quantitative data exist.

The purpose of this study was to determine the biomechanical differences between fresh and formalin-fixed spine specimens, using L1–2 motion segments from six 16-week-old calf spines. The range of motion and neutral zone were determined in flexion-/extension, left/right axial rotation, and right/left lateral bending.

The range of motion decreased in the formalin fixed specimens by as much as 80%, and the neutral zone by as much as 96%. The results of this study therefore imply that, for biomechanical testing, formalin-fixed specimens are not representative of the in vivo conditions.  相似文献   

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Abstract: This article evaluates the influence of an opening of the blood-brain barrier (BBB) on compounds in brain extracellular fluid. The concentrations of amino acids and some other primary amines were determined in dialysates sampled from the right parietal cortex of rats before and after an intracarotid infusion of protamine sulfate. Extravasated plasma proteins were visualized by Evans blue/albumin and immunohistochemistry. CSF albumin— an indicator of blood-CSF barrier opening—was quantified with immunoelectrophoresis. The brains were macroscopically edematous after 10 mg but not after 5 mg of protamine sulfate. The higher dose led to a 50% death rate. The concentrations of amino acids did not change 10 min after the BBB opening. No significant alterations in the amino acid concentrations were observed after the lower dose. The concentrations of glutamate, aspartate, GABA, glycine, taurine, and phosphoethanolamine increased significantly within 50–80 min after the infusion of 10 mg of protamine sulfate. CSF albumin levels were significantly increased 1 h after infusion. We conclude that a dysfunction of the BBB, of a degree known to induce brain edema (10 mg of protamine sulfate), significantly increases the extracellular concentration of excitatory amino acids, GABA, taurine, and phosphoethanolamine in the extracellular space.  相似文献   
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