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101.
OBJECTIVE: To compare serum concentrations of 1,25-dihydroxycholecalciferol (1,25-[OH]2D3) and 25-hydroxycholecalciferol (25-[OH]D3) in healthy control dogs and dogs with naturally occurring acute renal failure (ARF) and chronic renal failure (CRF). ANIMALS: 24 control dogs, 10 dogs with ARF, and 40 dogs with CRF. PROCEDURE: Serum concentrations of 1,25-(OH)2D3 were measured by use of a quantitative radioimmunoassay, and serum concentrations of 25-(OH)D3 were measured by use of a protein-binding assay. RESULTS: Mean +/- SD serum concentration of 1,25-(OH)2D3 was 153 +/- 50 pmol/L in control dogs, 75 +/- 25 pmol/L in dogs with ARF, and 93 +/- 67 pmol/L in dogs with CRF. The concentration of 1,25-(OH)2D3 did not differ significantly between dogs with ARF and those with CRF and was in the reference range in most dogs; however, the concentration was significantly lower in dogs with ARF or CRF, compared with the concentration in control dogs. Mean +/- SD concentration of 25-(OH)D3 was 267 +/- 97 nmol/L in control dogs, 130 +/- 82 nmol/L in dogs with ARF, and 84 +/- 60 nmol/L in dogs with CRF. The concentration of 25-(OH)D3 was significantly lower in dogs with ARF or CRF, compared with the concentration in control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: The concentration of 1,25-(OH)2D3 was within the reference range in most dogs with renal failure. Increased serum concentrations of parathyroid hormone indicated a relative deficiency of 1,25-(OH)2D3. A decrease in the serum concentration of 25-(OH)D3 in dogs with CRF appeared to be attributable to reduced intake and increased urinary loss. 相似文献
102.
Steinbach G Kröll U Meyer H Methner U 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(7-8):281-287
The development of the antibody concentration against lipopolysaccharide (LPS) of S. Typhimurium und S. Choleraesuis in rearing pigs during the fattening period and in breeding sows of the corresponding age was recorded. The studies revealed the following results. Antibodies of isotypes IgG1 and IgG2 revealed a more pronounced specificity against the according Salmonella serovar than IgM antibodies. The calculated "antibody percent value" based on the total amount of Salmonella antibodies is mainly determined by the IgM antibodies in sera and meat juice, respectively. In fattening pigs a significant increase of antibodies against IgM and total Ig was observed between week 3 and 10 after beginning of the rearing period. In breeding pigs this increase was detectable already earlier. In only 3 out of 10 groups an increase of IgG1 and IgG2 was also seen. The detected significant increase of total Ig and IgM in the other groups might be the result of a less intensive exposure to salmonellas or it might be due to an increase of unspecific antibodies induced by other antigens. Serological investigations represent a valuable tool to record the intensity and development in time of the Salmonella exposure in pigs farms. Examination of total Ig is an appropriate method to detect pig herds with a high level of Salmonella exposure, for detailed epidemiological studies in pig farms the examination of antibody isotypes will give more comprehensive information. 相似文献
103.
Horses may be exposed to aflatoxin B(1) (AFB(1)) via inhalation of mouldy dust, leading to high exposure of olfactory and respiratory tissues. In the present study the metabolic activation of AFB(1) was examined in olfactory and respiratory tissues in horse. The results showed covalent binding of AFB(1)-metabolites in sustentacular cells and cells of Bowman's glands in the olfactory mucosa, in some cells of the surface epithelium of nasal respiratory, tracheal, bronchial and bronchiolar mucosa and in some glands in these areas. Immunohistochemistry revealed that cells expressing proteins reacting with CYP 3A4- and CYP 2A6/2B6-antibodies had a similar distribution as those having capacity to activate AFB(1). Our data indicate that the cell-specific activation of AFB(1) correlates with presence of some CYP-enzymes in olfactory and respiratory tissues in horse. 相似文献
104.
Hässig M 《Schweizer Archiv für Tierheilkunde》2003,145(2):70-74
The Delvo-P-test (Gist-brocades nr, Delft, The Netherlands) is based on biological detection of antibiotics in the milk. According to the procedure of the manufacture the test is suited for bulk milk processing factories. Problems arise when the test is used on milk samples of a single cow. Buffers, cells, bacteria, cell contents, and desinfection without using antibiotics may give false positive and false negative results. An error up to 44.8% was detected on single cow milk samples. The test is well suited for bulk milk, where the processing of milk follows a biological procedure as for cheese. The use on single cow milk samples to prove absence of antibiotics is not recommended. 相似文献
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108.
OBJECTIVES: To evaluate the effects of radiation synovectomy (RSYN) with holmium-166 ferric hydroxide macroaggregate (Ho-166 FHMA) on synovium and synovial fluid in normal metacarpo- and metatarsophalangeal joints of horses and to determine intraarticular distribution of radioactivity after Ho-166 FHMA treatment. STUDY DESIGN: Either Ho-166 FHMA or nonradioactive Ho-165 FHMA was injected into metacarpo- or metatarsophalangeal joints. ANIMALS: Six adult mixed-breed horses without any clinical evidence of metacarpo- or metatarsophalangeal joint disease. METHODS: Joints were injected with a single high dose of Ho-166 FHMA (mean, 1,000 MBq/joint) or a nonradioactive Ho-165 FHMA preparation (controls). Clinical examination, arthroscopy, synovial fluid analyses, and histologic studies were performed to detect effects of RSYN. Scintigraphy was used to localize intraarticular distribution of Ho-166 FHMA. RESULTS: Ho-166 FHMA treatment induced joint inflammation leading to regional edema, effusion, and scar tissue formation. Scintigraphy revealed the highest intensity of radioactivity in the proximal plantar joint pouch, at which the Ho-166 FHMA treatment caused multifocal necrosis. In the dorsal joint pouch, however, arthroscopic study and histologic analysis showed very little effect of RSYN. There was no regeneration of synovium evident within 2 months. Synovial fluid protein concentration was significantly (P <.01) elevated, and some residual radioactivity remained for 5 days after Ho-166 FHMA injection. CONCLUSIONS: Injection of a single high dose of Ho-166 FHMA caused multifocal necrosis of synovium and deep, soft-tissue injury in equine fetlock joints. CLINICAL RELEVANCE: Inflamed equine joints with synovial lining hyperplasia could benefit from Ho-166 FHMA-induced radiation synovectomy if excessive scar tissue formation can be avoided. 相似文献
109.
The accuracy of heart rate estimation by cardiac auscultation over a 15-second period, and the influence of clinical experience on accuracy were evaluated in a dog with chronic atrial fibrillation by test subjects of varying experience. Only 30% of all test subjects provided accurate heart rate estimates. Board-certified specialists, medicine residents, and experienced nurses were significantly more accurate in their estimates than surgery residents and students. Accurate estimates were provided by 12.5% of surgery residents and students, as opposed to 64% of the other test subjects. Auscultatory estimates of heart rate in atrial fibrillation may be significantly inaccurate, and under some circumstances they may not provide a sound basis for making clinical decisions. 相似文献
110.
Dorn C Schroeter A Helmuth R 《Berliner und Münchener tier?rztliche Wochenschrift》2002,115(7-8):252-258
The National Salmonella Reference Laboratory (NRL-Salm) of the Federal Institute for Health Protection of Consumers and Veterinary Medicine receives putative Salmonella isolates originating from animals, food, feed and the environment for typing. This report summarises the results of the sero- and phagetyping studies. In livestock S. Typhimurium DT 104 with 24% and S. Enteritidis PT 4 with 9% of all isolations predominate like in the human isolates. These sero- and phagetypes are frequently isolated from food as well and consequently can reach the consumer via the food chain. 相似文献