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41.
The atomic force microscope (AFM) was used to image an electrode surface at atomic resolution while the electrode was under potential control in a fluid electrolyte. A new level of subtlety was observed for each step of a complete electrochemical cycle that started with an Au(111) surface onto which bulk Cu was electrodeposited. The Cu was stripped down to an underpotential-deposited monolayer and finally returned to a bare Au(111) surface. The images revealed that the underpotential-deposited monolayer has different structures in different electrolytes. Specifically, for a perchloric acid electrolyte the Cu atoms are in a close-packed lattice with a spacing of 0.29 +/- 0.02 nanometer (nm). For a sulfate electrolyte they are in a more open lattice with a spacing of 0.49 +/- 0.02 nm. As the deposited Cu layer grew thicker, the Cu atoms converged to a (111)-oriented layer with a lattice spacing of 0.26 +/- 0.02 nm for both electrolytes. A terrace pattern was observed during dissolution of bulk Cu. Images were obtained of an atomically resolved Cu monolayer in one region and an atomically resolved Au substrate in another in which a 30 degrees rotation of the Cu monolayer lattice from the Au lattice is clearly visible. 相似文献
42.
Hirsch VM Mitcham SC Dunn DK 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1984,13(2):16-20
An unusual combination of blood cytopenias and monocytic proliferation was observed in a dog. Initial hematologic findings included severe thrombocytopenia, neutropenia, mild nonregenerative anemia and apparently normal bone marrow. Subsequently, a severe persistent monocytosis developed and the bone marrow became populated with monocytes and cytophagic macrophages. Splenomegaly was due to reticuloendothelial hyperplasia and extramedultary hematopoiesis. Treatment consisted of splenectomy and azathioprine but the response was poor and the dog was euthanized. Postmortem examination revealed a hypocellular bone marrow which contained moderate numbers of monocytes and plasma cells. Neoplastic proliferation was absent in visceral organs. No definite diagnosis was established; chronic blood cell consumption, perhaps immune-mediated, may have been responsible for the extensive reticuloendothelial hyperplasia and cytophagia. 相似文献
43.
Trent AM Bailey JV 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(1):16-19
A three year old Charolais bull was examined because of anorexia and depression of five days duration and progressive abdominal distention. Intestinal obstruction was diagnosed. A right flank celiotomy allowed diagnosis and correction of a herniated jejunoileal loop through the right lateral ligament of the bladder. An annular constriction located in mid-ileum was by-passed by ileocecal side-to-side anastomosis. The bull's appetite and fecal production returned to normal within 72 hours of surgery. Ten months following discharge the bull was reported to be well. 相似文献
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1. The effect of feeding the detergent, sodium lauryl sulphate at concentrations up to 10 g/kg diet on egg‐shell quality was examined in laying hens at 24, 36 and 48 weeks of age.
2. Lauryl sulphate at 2.5 g/kg or more in the diet significantly increased shell breaking strength, shell thickness and shell weight at 24 and 36 weeks. In 48‐week‐old hens only shell breaking strength was increased significantly. Egg production and egg weight were not affected significantly by lauryl sulphate.
3. Lauryl sulphate might increase these measures of quality by increasing shell deposition and/or shell elasticity. 相似文献
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In the period December 1967 through April 1969 eight spontaneous cases of pseudorabies in Danish red foxes were demonstrated by virus isolation. One fox had been kept in captivity, the remaining seven were free-living. Five of the foxes were found dead, while three, presenting abnormal behaviour when encountered, had been killed. 相似文献
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