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101.
Addison L. Lawrence Joe Fox Frank L. Castille 《Journal of the World Aquaculture Society》1981,12(1):271-280
Although ethylenediaminetetraacetic acid (EDTA) is used routinely in the intensive culture of penaeid shrimp larvae to increase both the percentage of eggs that hatch and the survival of larvae, the mode of action is not known. To explain EDTA's beneficial effect this study compares the toxicities of copper and manganese divalent ions in the presence and absence of 10 mg EDTA/liter seawater. Toxicity was evaluated in terms of the percentage of Penaeus stylirostris nauplii surviving after 12 and 24 hours of exposure to either copper or manganese and in terms of the percentage of nauplii that metamorphose to the protozoeal stage. In the absence of EDTA, copper and manganese ions were toxic to nauplii with copper causing 100% mortality at a much lower concentration (20 μM) than manganese (20,000 μM). In the presence of EDTA, survival of nauplii exposed to copper was increased but survival of nauplii exposed to manganese was not affected. At concentrations lower than the levels that reduce survival, copper ions (0.2 μM) and manganese ions (2 μM) reduce the percentage of nauplii that metamorphose to protozoea. In the presence of EDTA, the percentage of nauplii that metamorphose to protozoea is increased with both nauplii exposed to copper ions and nauplii exposed to manganese ions. The beneficial effects of EDTA are probably due to the chelation of copper and manganese ions by EDTA. Chelation lowers the free concentration of these ions and thus reduces their toxicities. 相似文献
102.
Hypertropic cardiomyopathy and hyperthyroidism in the cat 总被引：2，自引：0，他引：2
S K Liu M E Peterson P R Fox 《Journal of the American Veterinary Medical Association》1984,185(1):52-57
In a 21/2-year period, hypertrophic cardiomyopathy was found at necropsy of 23 cats that died (13 cats) or were euthanatized (10) because of problems associated with hyperthyroidism. Of these, 4 (17%) also had evidence of cardiac failure (pulmonary edema or pleural effusion). The mean body weight of the cats with hyperthyroidism and hypertrophic cardiomyopathy was significantly less (P less than 0.001) than that of clinically normal cats and cats with primary cardiomyopathy (congestive or restrictive) or excessive moderator band cardiomyopathy. In addition, the ratio of heart weight to body weight was significantly greater (P less than 0.001) in the 23 hyperthyroid cats than in the normal cats and cats with primary cardiomyopathy. Twenty (87%) of the cats had symmetric hypertrophy of the ventricular septum and left ventricular free wall, whereas the remaining 3 cats had disproportionate thickening of the ventricular septum, compared with the free wall, similar to what is found in cats with asymmetric hypertrophic cardiomyopathy. Histologic cardiac abnormalities included large, hyperchromatic nuclei, interstitial fibrosis, endocardial fibroplasia, fibrosis of the atrioventricular node, and marked disorganization of cardiac muscle cells. The study showed that hypertrophic cardiomyopathy develops in most hyperthyroid cats, some of which also develop congestive heart failure. Although the signs of heart disease in primary myocardial disease and thyrotoxic disease are similar, the characteristic signalment and clinical signs of hyperthyroidism should lead one to suspect the association of hypertrophic cardiomyopathy with the hyperthyroidism. 相似文献
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Abstract— —An astrocytoma in a 9-year-old Boxer dog was found on postmortem to have invaded the sensory and motor regions of the neocortex in the right cerebrum. The limbic lobe, internal capsule and corpus callosum were also involved. Clinical symptoms included hyperaesthesia on left side of the body, poor placing response in left fore-leg, convulsions and circling away from the affected side. EEG revealed focal spike discharges which were localized around the cortical area affected.
Résumé— —Chez un chien boxer âgé de 9 ans, un astrocytome a été trouvéà l'autopsie, ayant invadé les régions sensorielle et motrice du néocortex dans le cerveau droit. Le lobe limbique, la capsule interne et le corps calleux étaient également impliqués. Les symptomes cliniques incluaient l'hyperesthésie de la région droite, mauvaise réaction de placement de la patte antérieure gauche, convulsions et tournement de côté de la région affectée. EEG révéla des décharges pointues focales localisées autour de la région corticale affectée.
Zusammenfassung— — Ein Astrocytom bei einer 9 Jahre alten Bulldogge wurde bei der Sektion gefunden. Dieses war in die sensorischen und motorischen Regionen des Neopallium im rechten Gehirn eingedrungen. Der limbische Lappen, die innere Kapsel und das Corpus callosum waren ebenfalls beteiligt. Die klinischen Symptome bestanden in Hyperaesthesie der linken Kärperhölfte, schlechte Bewegungen im linken Vorderbein, Konvulsionen und Fortbewegungen von der betroffenen Seite. EEG zeigte fokale Aehren-Entladungen, die in der betroffenen Rindenzone lokalisient wurden. 相似文献
Résumé— —Chez un chien boxer âgé de 9 ans, un astrocytome a été trouvéà l'autopsie, ayant invadé les régions sensorielle et motrice du néocortex dans le cerveau droit. Le lobe limbique, la capsule interne et le corps calleux étaient également impliqués. Les symptomes cliniques incluaient l'hyperesthésie de la région droite, mauvaise réaction de placement de la patte antérieure gauche, convulsions et tournement de côté de la région affectée. EEG révéla des décharges pointues focales localisées autour de la région corticale affectée.
Zusammenfassung— — Ein Astrocytom bei einer 9 Jahre alten Bulldogge wurde bei der Sektion gefunden. Dieses war in die sensorischen und motorischen Regionen des Neopallium im rechten Gehirn eingedrungen. Der limbische Lappen, die innere Kapsel und das Corpus callosum waren ebenfalls beteiligt. Die klinischen Symptome bestanden in Hyperaesthesie der linken Kärperhölfte, schlechte Bewegungen im linken Vorderbein, Konvulsionen und Fortbewegungen von der betroffenen Seite. EEG zeigte fokale Aehren-Entladungen, die in der betroffenen Rindenzone lokalisient wurden. 相似文献
109.
A 12-year-old, neutered male domestic shorthair cat was evaluated with a life-long history of intermittent, predominantly small bowel diarrhea and a 3 day history of hematochezia. At presentation, the cat had increased liver enzyme activities and an inflammatory leukogram. Histopathology demonstrated inflammatory bowel disease (IBD), cholangiohepatitis and pancreatitis. The cholangiohepatitis was associated with a multi-drug resistant Enterococcus faecium. Gallbladder agenesis was also documented. Treatment with vancomycin was safely instituted for 10 days. Clinical signs resolved, however, cure of the bacterial cholangiohepatitis was not achieved. The risk of vancomycin resistant enterococci (VRE) in human and veterinary medicine is discussed. 相似文献
110.