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971.
Hypocalcemia and hypomagnesemia are common in horses with sepsis and endotoxemia. We hypothesize that endotoxemia triggers a systemic inflammatory response that results in hypocalcemia and hypomagnesemia. The goal of this study was to determine the effect of endotoxin (lipopolysaccharide [LPS]) administration to healthy horses on serum parathyroid hormone (PTH), ionized calcium (Ca2+) and total calcium (tCa), ionized magnesium (Mg2+) and total magnesium (tMg), phosphate (Pi), potassium (K+), sodium (Na+), chloride (Cl-), and insulin concentrations, and on the urinary excretion of these electrolytes. Twelve mares were infused with Escherichia coli LPS (30 ng/kg/h i.v.) for 1 hour. Six mares were infused with saline (controls). In LPS-infused horses, heart rate increased significantly from (mean +/- SD) 40.0 +/- 1.3 to 70.0 +/- 9.0 beats/min, respiratory rate from 12.7 +/- 1.0 to 21.1 +/- 3.0 breaths/min, body temperature from 37.4 +/- 0.3 to 38.9 +/- 0.6 degrees C, and tumor necrosis factor-alpha concentrations from 6.6 +/- 3.5 to 507 +/- 260 pg/mL (P < .05). White blood cell count decreased significantly from 7570 +/- 600 to 1960 +/- 560 cells/ microL. Serum concentrations of Ca2+ decreased from 6.5 +/- 0.3 to 6.0 +/- 0.3 mg/dL, of Mg2+ from 0.53 +/- 0.06 to 0.43 +/- 0.04 mM, of tMg from 0.78 +/- 0.05 to 0.62 +/- 0.08 mM, of K+ from 4.3 +/- 0.4 to 3.0 +/- 0.5 mEq/L, and of Pi from 3.4 +/- 0.5 to 1.7 +/- 0.5 mg/dL (all P < .05). PTH increased significantly from 1.3 +/- 0.4 to 6.0 +/- 5.2 pM; however, in some horses (n=2), PTH did not increase despite hypocalcemia. Insulin increased significantly from 9.4 +/- 3.6 to 50.5 +/- 9.6 microIU/mL (n=3). Urinary fractional excretion of Ca2+ decreased significantly from 4.7 +/- 1.4 to 1.7 +/- 1.2%, of Mg2+ from 36.6 +/- 6.5 to 11.7 +/- 7.3%, and of K+ from 37.9 +/- 11.3 to 17.7 +/- 6.2%. Fractional excretion of Pi increased from 0.02 +/- 0.02 to 0.14 +/- 0.07% and of Na+ from 0.26 +/- 0.13% to 1.2 +/- 0.5%. No changes were found in serum tCa, Na+, and Cl- concentrations. In conclusion, endotoxemia in horses resulted in electrolyte abnormalities that included hypocalcemia, hypomagnesemia, hypokalemia, hypophosphatemia, and increased serum PTH and insulin concentrations.  相似文献   
972.
OBJECTIVE: To identify the normal gastric acid secretion profile in dogs and determine the degree of gastric acid suppression associated with 4 gastric acid suppressants. ANIMALS: 12 healthy Beagles. PROCEDURE: Intragastric pH was measured continuously for 24-hour periods with a digital recording system placed via a gastrostomy tube. Baseline measurements were obtained when food was withheld and when dogs were fed a standard diet. Dogs were then treated with ranitidine (2 mg/kg, IV, q 12 h), famotidine (0.5 mg/kg, IV, q 12 h), pantoprazole (1 mg/kg, IV, q 24 h), omeprazole (1 mg/kg, PO, q 24 h), or saline solution for 7 days; intragastric pH was recorded on days 0, 2, and 6. Subsequently, the effects of administering famotidine (0.5 mg/kg, IV, q 8 h; 6 dogs) and omeprazole as a suspension (1 mg/kg, PO, q 12 h; 6 dogs) were evaluated. Median 24-hour intragastric pH, percentage of time pH was > or = 3, and percentage of time pH was > or = 4 were determined. RESULTS: Median pH, percentage of time pH was > or = 3, and percentage of time pH was > or = 4 were all significantly higher when food was withheld than when dogs were fed. Famotidine, pantoprazole, and omeprazole significantly suppressed gastric acid secretion, compared with saline solution, as determined on the basis of median 24-hour pH and percentages of time pH was > or = 3 or > or = 4. However, ranitidine did not. Omeprazole suspension suppressed gastric acid secretion. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that in healthy dogs, famotidine, pantoprazole, and omeprazole significantly suppress gastric acid secretion. Twice daily administration of a suspension of omeprazole, was the only regimen tested that approached the potential therapeutic efficacy for acid-related disease when assessed by criteria used for human patients.  相似文献   
973.
Summary In this study we investigated the effect of the acetyl-L-carnitine (ALC) supplementation on the myenteric neurons of the jejunum of rats made diabetic at the age of 105 days by streptozotocin (35 mg/kg body weight). Four groups were used: non-diabetic (C), non-diabetic supplemented with ALC (CC), diabetic (D), diabetic supplemented with ALC (DC). After 15 weeks of diabetes induction the blood was collected by cardiac puncture to evaluate glycaemia and glycated haemoglobin. Next the animals were killed and the jejunum was collected and subjected to whole-mount preparation to evidence the myenteric neurons through the histochemical technique of the NADH-diaphorase. The neuronal counts were made in 80 microscopic fields, in tissue samples of five animals of each group. The profiles of the cell bodies of 1000 neurons per group were analysed. Diabetes induced a significant increase in the area of the cell body and decrease in the number of NADH-diaphorase positive myoenteric neurons. ALC suplementation to the diabetic group promoted smaller hypertrophic effects and less neuronal loss than in the myoenteric neurons of the diabetic rats, and in addition diminished the body weight decrease and reduced the fasting glycaemia.  相似文献   
974.
975.
This paper estimates the financial incentive to control paratuberculosis on dairy farms by establishing the level of expenditure that would minimise the total cost of the disease (output losses plus control expenditure). Given the late onset of the clinical signs and the lack of treatments, control was focused on minimising the financial impact of paratuberculosis by adjusting the dairy cow replacement policy. The optimum replacement policies for disease-free herds and infected herds were compared by using dynamic programming. At the standard settings, the disease justified adjusting the culling policy; under constant bioeconomic assumptions, it reduced the expected annuity from milk production under the optimal replacement policy by about 10 per cent (27 pounds sterling per cow annually), a considerably lower figure than for other major endemic diseases that affect dairy cows in the uk. The effect was even less at lower milk prices, suggesting that there is at present little incentive for dairy farmers to put more resources into controlling the disease. However, the incentive could be increased if more information were available about how best to manage the disease under specific farm circumstances. Any effect that paratuberculosis may have on the future demand for milk and hence on milk prices would also be an important consideration.  相似文献   
976.
OBJECTIVE: To compare bursting tension of arteries > or =3 mm in diameter sealed with ultrasonic energy (UE) with arteries ligated with suture. STUDY DESIGN: Experimental, nested factorial design. SAMPLE POPULATION: Vascular segments from canine cadavers. METHODS: Arterial segments (12) were collected from each of 16 canine cadavers and equally divided into 2 groups based on vessel diameter (medium, 3.0- < 4.5 mm; large, 4.5 - < or =6.0 mm). Arterial specimens (3) from each group were sealed with either UE (Harmonic Scalpel, HS, power level 3) or suture ligation. The mean bursting pressure and tension were determined and compared. RESULTS: Bursting tension was significantly higher (P< .0001) for sutured arteries than UE-occluded arteries, irrespective of size. Bursting tension was significantly higher (P=.0013) for medium than large UE-occluded arteries, whereas there was no difference associated with size for ligated arteries. UE energy failed to seal 1 medium artery and 7 large arteries. Compared with normal blood pressure, bursting pressures were 3.5 times greater for sutured arteries irrespective of size, 1.8 times greater for medium UE-occluded arteries, and approached normal blood pressure for large UE-occluded arteries. CONCLUSION: At the power level tested, UE should not be used to seal arteries > 4.5 mm in diameter. Suture provided an optimal seal for arteries < or =6.0 mm in diameter. CLINICAL RELEVANCE: Use of UE to occlude arteries during laparoscopic surgery is advantageous because only 1 instrument is required to simultaneously cut and coagulate tissue, but care should be exercised where large arteries might be encountered.  相似文献   
977.
Funisitis associated with leptospiral abortion in an equine placenta   总被引:1,自引:0,他引:1  
Funisitis, inflammation of the umbilical cord, is well recognized in human placentas. This report describes a case of funisitis associated with leptospiral infection in the placenta of a Thoroughbred foal born prematurely. The umbilical cord had diffuse superficial yellow discoloration along its entire length. Microscopic evaluation showed an exudate of neutrophils admixed with fibrin on the surface. Warthin-Starry staining showed spirochetes in the Wharton's jelly of the umbilical cord. A locally extensive, severe placentitis not involving the star and allantoic cystic hyperplasia were the other lesions observed in the allantochorion. Leptospira funisitis is similar to the funisitis of congenital syphilis in humans, although there are some major microscopic differences. In Leptospira funisitis, lesions were limited to the cord surface, whereas in lesions in human umbilical cords with Treponema pallidum infection, the changes are observed mostly around the vessels and in the Wharton's jelly.  相似文献   
978.
Nineteen racing pigeons aged from one to five years were examined postmortem. pcr tests showed that the spleens of 16 of them were positive for pigeon circovirus, the livers of six were positive, and blood from one of them was positive for the virus. Five of 44 embryos in embryonated eggs collected from three lofts were positive by pcr, but swabs taken from the crops of 64 adult birds which were feeding one- to 10-day-old squabs in these three lofts were negative for the viral dna.  相似文献   
979.
OBJECTIVE: To evaluate the use of polyamide bands, manufactured for securing electrical cables, for repair of oblique femoral fractures in rabbits. STUDY DESIGN: Experimental study. ANIMALS: Twelve nulliparous, 21-25-week-old, California female rabbits. METHODS: Rabbits were divided into 3 groups (n=4) and studied for 14, 28, or 56 days. A Z-shaped mid-diaphyseal femoral osteotomy was repaired with a 2.5 mm intramedullary pin and a polyamide 6.6 cerclage band. Healing was evaluated at intervals by physical examination, limb use, femoral radiographs, and callus histology. RESULTS: Rabbits had early limb use with good wound healing. From the 1st day, movement of the hip and stifle joints was satisfactory. Radiographically, fractures were healed at 28 days. Histologically, there was no foreign body reaction and bone healing was normal. CONCLUSION: Nylon cerclage band application was accomplished easily, maintained reduction, and resulted in good healing and limb use. CLINICAL RELEVANCE: Sterilized nylon bands, manufactured for electrical use, can be used for cerclage in rabbits.  相似文献   
980.
OBJECTIVE: To determine response rates and survival times for cats with lymphoma treated with the University of Wisconsin-Madison chemotherapy protocol. DESIGN: Retrospective study. ANIMALS: 38 cats with lymphoma. PROCEDURE: Medical records were reviewed, and information on age, sex, breed, FeLV and FIV infection status, anatomic form, clinical stage, and survival time was obtained. Immunophenotyping was not performed. RESULTS: Mean +/- SD age of the cats was 10.9 +/- 4.4 years. Overall median survival time was 210 days (interquartile range, 90 to 657 days), and overall duration of first remission was 156 days (interquartile range, 87 to 316 days). Age, sex, anatomic form, and clinical stage were not significantly associated with duration of first remission or survival time. Eighteen of the 38 (47%) cats had complete remission, 14 (37%) had partial remission, and 6 (16%) had no response. Duration of first remission was significantly longer for cats with complete remission (654 days) than for cats with partial remission (114 days). Median survival time for cats with complete remission (654 days) was significantly longer than median survival time for cats with partial remission (122 days) and for cats with no response (11 days). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that a high percentage of cats with lymphoma will respond to treatment with the University of Wisconsin-Madison chemotherapy protocol. Age, sex, anatomic form, and clinical stage were not significantly associated with duration of first response or survival time, but initial response to treatment was.  相似文献   
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