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51.
Thyroid cell membranes contain a multiplicity of gangliosides, some of which inhibit thyrotropin binding to thyroid membranes. The most potent inhibitor is a ganglioside which is present in only trace amounts and appears to have a novel structure. Thyroid gangliosides may play a role in relaying the hormonal message to the thyroid cell.  相似文献   
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Knowledge of the most common presenting complaints and diagnoses in companion animals is valuable in preparing veterinary students and veterinarians to manage the most frequently observed conditions in clinical practice. Pet insurance databases provide access to large sample populations and have been previously used to describe disease incidence in companion animals. The aim of this study was to determine the incidence of presenting complaints and diagnoses in insured Australian dogs through the use of a pet insurance database. Analysis of a de-identified dataset containing pet insurance claims associated with presenting complaints and diagnoses from 488,472 insured Australian dogs insured in the years 2016 and 2017, was performed. Annual incidence rates of presenting complaints and diagnoses were calculated and expressed as, number of events per 1,000 dog years at risk. The presenting complaints with the highest incidence were vomiting (14.21 events per 1,000 dog years at risk in 2016, 15.80 events per 1,000 dog years at risk in 2017) and pruritus (8.79 events per 1,000 dog years at risk in 2016, 10.30 events per 1,000 dog years at risk in 2017). Presenting complaints affecting the gastrointestinal system were the most common (19.20 events per 1,000 dog years at risk in 2016, 20.77 events per 1,000 dog years at risk in 2017). The diagnoses with the highest incidence were otitis externa (34.12 events per 1,000 dog years at risk in 2016, 34.82 events per 1,000 dog years at risk in 2017) and dermatitis (28.05 events per 1,000 dog years at risk in 2016, 29.99 events per 1,000 dog years at risk in 2017). Diagnoses affecting the integument were the most common (216.56 events per 1,000 dog years at risk in 2016, 219.06 events per 1,000 dog years at risk in 2017). The results from this study can aid in the design of relevant veterinary curricula and may be helpful in prioritising research on common clinical conditions.  相似文献   
53.
Toxigenic strains of Pasteurella multocida were readily differentiated from non-toxigenic strains by an agarose overlay method using bovine turbinate cells or bovine lung cells. Cells which were young and densely confluent were best suited to this assay. The incubation period required to distinguish toxigenic strains was dependent on the confluence of the monolayers, which was affected by the seeding rate, cell passage level and growth time prior to overlay. The agarose overlay method correctly identified 11 of 11 reference strains of Pasteurella multocida, and visible cytotoxic changes were present in the monolayers after 48 to 65 h. Outbreaks of the enzootic form of atrophic rhinitis in 2 New South Wales piggeries were associated with the isolation of toxigenic type D strains of P. multocida.  相似文献   
54.
On the basis of clinical signs and histological findings eight 9-month-old male rusa deer ( Cervus timorensis ) were diagnosed with sheep associated-malignant catarrhal fever. Following a variable course involving rectal temperatures around 40.5°C, depression, inappetence, diarrhoea, corneal opacity and hypopyon all animals died or were euthanased over a 5-week period. Severe multifocal vasculitis, mainly periglomerular and in the arcuate vessels were consistent histological findings which in the past have been adequate to confirm clinical diagnosis of sheep associated-malignant catarrhal fever. A nested poly-merase chain reaction test has been used to detect a sheep associated-malignant catarrhal fever PRC product, 238 base-pairs in size, in DNA extracted from lymphocyte preparations. The result supported the diagnosis of sheep associated-malignant catarrhal fever in these deer.  相似文献   
55.
SUMMARY A three-year-old neutered female Border Collie was presented with in-appetence, vomiting and diarrhoea. Abdominal radiographs revealed an obstructive pattern but no physical obstruction was evident at laparotomy. A diagnosis of chronic intestinal pseudo-obstruction was made based on histopathological changes in intestinal biopsies. Treatment was unsuccessful and the dog deteriorated progressively until euthanased five weeks after presentation.  相似文献   
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Pectin gels were induced by monovalent salts (0.2 M) concurrently with deesterification of high methoxy pectin using a salt-independent orange pectin methylesterase (PME). Constant pH was maintained during deesterification and gelation. If salt or PME was absent, the pectin did not form a gel. The gel strength was influenced by both pH and species of monovalent cation. At pH 5.0, the pectin gel induced by KCl was significantly stronger than the NaCl-induced gel. In contrast, a much stronger gel was produced in the presence of NaCl as compared to KCl at pH 7.0. LiCl did not induce pectin gelation at either pH. Molecular weights of pectins increased from 1.38 x 10(5) to 2.26 x 10(5) during NaCl-induced gelation at pH 7. One proposal to explain these pectin molecular weight changes is a hypothetical PME transacylation mechanism. However, these pectin molecular weight changes can also be explained by metastable aggregation of the enzymatically deesterified low methoxy pectin. We postulate that gelation was induced by a slow deesterification of pectin under conditions that would normally salt out (precipitate) low methoxy pectin in the absence of PME.  相似文献   
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The neuron-specific protein GAP-43 is associated with the membrane of the nerve growth cone and thus may be important to the activity of this distinctive neuronal structure. Transient transfection of COS and NIH 3T3 cells with appropriate vectors resulted in expression of GAP-43 in these non-neuronal cells; as in neurons, transfected GAP-43 associated with the membrane. In addition, many long fine filopodial processes extended from the periphery of such transfected cells. Stable CHO cell lines expressing GAP-43 also exhibited processes that were more numerous, far longer, and more complex than those of CHO cell lines not transfected or transfected with control plasmids. Thus GAP-43 may directly contribute to growth cone activity by regulating cell membrane structure and enhancing extension of filopodial processes.  相似文献   
60.
Objective To determine the amounts of organophosphorous and synthetic pyrethroid residues on Queensland wool sampled between 1995 and 1997, and to study if pesticide use changed during the period.
Design Estimated amounts of residues were obtained from a survey of Queensland wool clips, and information on pesticide use was obtained from a trace-back postal survey of flock managers.
Procedure Trends in amounts of residues over time were assessed using analysis of variance and simple linear regression models, and changes in pesticide use was assessed using x2 tests.
Results Significant linear reductions in organophosphorous (P = 0.0012), synthetic pyrethroid (P = 0.0044) and total (P = 0.0002) residues were detected. The proportion of woolgrowers treating for louse infestation (P = 0.0046) treating twice or more (P = 0.0006) and treating more than 4 months after shearing (P = 0.0001) decreased between 1994 and 1997. However, the proportion of growers who treated for blowfly strike (P = 0.0124) and used insect growth regulator pesticides increased (P < 0.0001). The use of handjetting to apply pesticides for blowfly strike control increased and the use of dips decreased (P < 0.0001).
Conclusion Residues of organophosphorous compounds and synthetic pyrethroids reduced in Queensland wool between 1994 and 1997. Although woolgrowers treated for louse infestation less, pesticide use to control blowfly strike increased. The increasing use of insect growth regulators in the industry needs to be monitored.  相似文献   
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