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991.
Feeding behavior is regulated by neural signals in the hypothalamus, but secretory activities of these signals in vivo and their relationship with spontaneous feeding remain to be solved. In the present study, we investigated the correlation between neuropeptide Y (NPY) and somatostatin (SRIF) profiles in cerebrospinal fluid (CSF) and spontaneous feeding behavior in goats. CSF samples were collected every 15 min for 8 h from the third ventricle and feeding behavior was observed throughout the experimental period. The spontaneous feeding behavior, the mean duration of which was 58 min, occurred with an interval of 146 min. NPY in the CSF fluctuated in an episodic fashion with a 145 min interval. Each NPY episode was followed by spontaneous feeding with a time lag of 24 min. SRIF levels in CSF changed more frequently in a pulsatile manner and were related to neither NPY profiles nor feeding behavior. These results suggest that NPY, but not SRIF, is a physiological signal to drive feeding in goats.  相似文献   
992.
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   
993.
For Apicomplexa (members) the host cell invasion is realized with the help of the organelles located at the apical tip of parasites. In this research paper the characterization of five chicken monoclonal antibodies (mabs) produced against Eimeria acervulina sporozoites is described. All mabs reacted with molecules belonging to the apical complex of chicken Eimeria sporozoites. On immunofluorescence assay (IFA) one mab, 8E-1, recognized an apical tip molecule present on all chicken Eimeria sporozoites, two mabs (8D-2 and HE-4) recognized an antigen present on the apical tip of the same two Eimeria species (E. acervulina and E. brunetti), another mab (5D-11) recognized an antigen present on the apical tip of other two species (E. acervulina and E. maxima) while one mab (8C-3) identified antigens present on the sporozoites and sporocysts wall of only E. acervulina. Besides the apical tip antigens, two mabs (HE-4 and 8D-2) recognized some proteins located in the anterior half of the sporozoites. Collectively, these mabs proved that the apical complex of chicken Eimeria sporozoites share one or more antigens that are expected to play a role in host cell recognition and invasion.  相似文献   
994.
The history, clinical signs and pathological findings in seven adult horses with histologically confirmed idiopathic granulomatous disease, primarily of the lungs, are reviewed. They ranged in age from eight to 21 years, five were geldings and two were females, they belonged to five breeds and there were no seasonal or geographical associations. The primary clinical signs were chronic weight loss, exercise intolerance and respiratory distress which did not respond to conventional treatment. The most consistent physical findings were depression, anorexia, tachycardia, tachypnoea and adventitious lung sounds. Thoracic radiographs revealed a diffuse, structured, nodular, interstitial pulmonary pattern in each horse. Haematological measurements suggested a chronic inflammatory process and the cytology of transtracheal washes was consistent with a mild suppurative inflammation. Idiopathic granulomatous pneumonia was confirmed histologically in each of the horses, either postmortem or by a lung biopsy. The horses responded poorly to medical treatment and only one of three treated horses is still alive.  相似文献   
995.
The combined occurrence of ocular pigment deposition and glaucoma has been described in Cairn Terriers. Recently, this condition was also observed in two other breeds: the Boxer (two cases) and the Labrador Retriever (one case). Six dogs were referred to the Ophthalmology section of the Department of Clinical Sciences of Companion Animals and to a private referral clinic because of glaucoma or blindness in one or both eyes. In five cases ophthalmic examination showed pigment depositions in the sclera around the entire circumference of the perilimbal zone. Eight enucleated eyes (four eyes of two Cairn Terriers, three eyes of two Boxers and one eye of a Labrador Retriever) were examined microscopically. All eyes showed the same findings: an extensive infiltration of large melanin-containing cells with an eccentric nucleus, located in the iris, ciliary body, retina, choroids and sclera. Transmission electron microscopy of two of the examined eyes revealed that the morphology of most of these cells was consistent with melanophages. While reports in the veterinary literature concerning this condition are limited the cells concerned have been described to be melanocytes. Further research is needed to conclusively identify the cell type. As described in the present report, the histologic and transmission electron microscopic findings suggest a different etiology of the ocular pigment deposition and glaucoma compared with the pigment dispersal syndrome in humans.  相似文献   
996.
Cytokine kinetics were examined in milk and in afferent and efferent lymph of the supramammary lymph node after intramammary infusion of endotoxin from Escherichia coli. Cows were sampled 0, 2 and 4h after infusion (p.i.). Neutrophils appeared in afferent lymph 2h p.i., and in efferent lymph and milk 4h p.i. The milk contained high concentrations of interleukin-8 (IL-8) at 2 and 4h p.i. IL-8 was also found in lymph, but at lower concentrations. The tumor necrosis factor-alpha (TNF-alpha) concentration tended to increase in afferent lymph at 2h p.i., and increased in milk at 4h p.i. The level of IL-1beta increased at 4h p.i. in milk, but was not detected in lymph. Interferon-gamma was not detected in any sample, at any time. The results indicate a primary role for IL-8 in the recruitment of neutrophils into the gland, and suggest that IL-1beta and TNF-alpha are not necessary for IL-8 production and release in response to endotoxin.  相似文献   
997.
OBJECTIVE: To estimate receiver-operating characteristic (ROC) curves for a competitive ELISA (c-ELISA) that is used in serodiagnosis of brucellosis in water buffalo and cattle, to determine the most appropriate positive cutoff value for the c-ELISA in confirmation of infection, and to evaluate species differences in c-ELISA function. SAMPLE POPULATION: Sera from 4 herds of cattle (n = 391) and 4 herds of water buffalo (381). PROCEDURE: Serum samples were evaluated for Brucella-specific antibodies by use of a c-ELISA. On the basis of previous serologic test results, iterative simulation modeling was used to classify animals as positive or negative for Brucella infection without the use of a gold standard. Accuracy of c-ELISA for diagnosis of infection was compared between cattle and water buffalo by comparison of areas under ROC curves. RESULTS: A positive cutoff value of 30% inhibition for c-ELISA yielded sensitivity and specificity estimates, respectively, of 83.9 and 92.6% for cattle and 91.4 and 95.4% for water buffalo. A positive cutoff value of 35% inhibition yielded sensitivity and specificity estimates, respectively, of 83.9 and 96.2% for cattle and 88.0 and 974% for water buffalo. Areas under ROC curves were 0.94 and 0.98 for cattle and water buffalo, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: ROC curves can be estimated by use of iterative simulation methods to determine optimal cutoff values for diagnostic tests with quantitative outcomes. A cutoff value of 35% inhibition for the c-ELISA was found to be most appropriate for confirmation of Brucella infection in cattle and water buffalo.  相似文献   
998.
OBJECTIVE: To determine effects of storage temperature and time on pH and specific gravity of and number and size of crystals in urine samples from dogs and cats. DESIGN: Randomized complete block design. ANIMALS: 31 dogs and 8 cats. PROCEDURE: Aliquots of each urine sample were analyzed within 60 minutes of collection or after storage at room or refrigeration temperatures (20 vs 6 degrees C [68 vs 43 degrees F]) for 6 or 24 hours. RESULTS: Crystals formed in samples from 11 of 39 (28%) animals. Calcium oxalate (CaOx) crystals formed in vitro in samples from 1 cat and 8 dogs. Magnesium ammonium phosphate (MAP) crystals formed in vitro in samples from 2 dogs. Compared with aliquots stored at room temperature, refrigeration increased the number and size of crystals that formed in vitro; however, the increase in number and size of MAP crystals in stored urine samples was not significant. Increased storage time and decreased storage temperature were associated with a significant increase in number of CaOx crystals formed. Greater numbers of crystals formed in urine aliquots stored for 24 hours than in aliquots stored for 6 hours. Storage time and temperature did not have a significant effect on pH or specific gravity. CONCLUSIONS AND CLINICAL RELEVANCE: Urine samples should be analyzed within 60 minutes of collection to minimize temperature- and time-dependent effects on in vitro crystal formation. Presence of crystals observed in stored samples should be validated by reevaluation of fresh urine.  相似文献   
999.
Five camelid mucocutaneous fibropapillomas with histologic features similar to equine sarcoids were diagnosed. They were characterized by a dermal fibroblastic proliferation and overlying, often ulcerated hyperplastic epidermis with thin rete pegs extending down into the dermis. Two of the tumors came from llamas and three from alpacas. Four of the animals were 6-year-old females. The fifth was a 6-year-old castrated male. The fibropapillomas were located on the nose, lip, and cheeks. One of the llama tumors waxed and waned before surgery and recurred and spread after surgery. None of the other tumors recurred. All five tumors were positive for papillomavirus (PV) DNA by polymerase chain reaction testing. Nucleotide sequence analysis of the PCR product from one of the llama fibropapillomas confirmed a unique PV. This report provides the microscopic and clinical features of fibropapillomas in camelids as well as evidence for a PV etiology.  相似文献   
1000.
Atrial natriuretic peptide (ANP) is a polypeptide hormone found in increased concentrations in the plasma of dogs with heart failure. However, problems arise in using ANP as a diagnostic marker for heart failure because of its short half-life in plasma, proteolysis post-collection and the necessity for a radioimmunoassay. The diagnostic utility of a proANP 31-67 ELISA for the detection of heart failure in dogs was evaluated using plasma collected from 31 dogs with clinical and radiographic signs of heart failure and control samples from 40 dogs considered to be free of cardiac disease. Log proANP 31-67 levels were significantly higher in the heart failure group (P < 0.001). In this population of dogs, using a cut-off value of 1,750 fmol/ml, the sensitivity and specificity of the assay were 83.9 per cent and 97.5 per cent, respectively. Using a cut-off of 1,350 fmol/ml, the sensitivity and specificity were 93.5 per cent and 72.5 per cent, respectively. It is concluded that a proANP 31-67 fragment ELISA should prove to be a useful diagnostic aid in naturally occurring canine heart failure.  相似文献   
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