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911.
Gelatinolytic activity was analysed to study whether elevated activity previously found at the tracheal level of the respiratory tract of horses with chronic obstructive pulmonary disease (COPD) could also be found at the lower part of the respiratory tract. Furthermore, presence and significance of the gelatinolytic matrix metalloproteinases (MMPs) MMP-2 and MMP-9 in respiratory secretions of healthy and COPD horses were determined. Elevated gelatinolytic matrix metalloproteinases were detected in bronchoalveolar and tracheobronchial secretions from COPD horses. The main pathologically elevated MMP was characterised to be MMP-9. Significantly increased MMP-9 activities as measured by gelatin zymography and Western blotting were found in all the respiratory samples from COPD horses compared to healthy horses. Elevation of active MMP-9 paralleled with increased gelatinase-associated lipocalin levels. Bronchoalveolar lavage fluid (BALF) epithelial cells, macrophages, neutrophils and lymphocytes expressed MMP-9 immunoreactivity demonstrated by immunocytochemistry and MMP-9 mRNA was expressed by bronchial epithelial cells of lung tissue section shown by in situ hybridisation. MMP-2 seems not to play a major role in chronic lung inflammation. No clear differences in MMP-2 or MMP-14 (a potent MMP-2 activator) levels were found when comparing the samples from COPD or healthy horses. These results suggests that MMP-9 could serve as a potential diagnostic marker for the active ongoing tissue remodelling in the acute phase of equine COPD. Increased gelatinolytic activity could be found at both tested respiratory tract levels. Therefore, tracheal epithelial lining fluid (TELF) samples can usefully serve as diagnostic material for detection of increased levels of the main gelatinolytic MMP, MMP-9, representing the entire diseased lung.  相似文献   
912.
Exposure and ecological risks to heavy metals (copper, zinc, manganese, iron) at Lochnivar and Blue Lagoon National Parks in wildlife dependent on the Kafue river contaminated with mining waste was evaluated. Samples included water, fish, grasses and Kafue Lechwe (Kobus leche kafuensis) liver. At both parks copper ranged from 0.03-0.04 mg/l; 3.0-6.0 mg/kg; 11.0-44.0 mg/kg; trace -199.0 mg/kg; while zinc was 0.01 mg/l; 32.0-82.0 mg/kg; 15.0-21.0 mg/kg; and 52.0-138.0 mg/kg; in water, fish, grasses and lechwe, respectively. Manganese ranges were 0.15-0.16 mg/l; 7.0-18.0 mg/kg; 51.0-145.0 mg/kg; and 40.0-53.0 mg/kg while iron ranges were 0.13-0.14 mg/l; 26.0-134.0 mg/kg; 1766.0-1797.0 mg/kg; and 131.0-856.0 mg/kg; in water, fish, grasses and lechwe, respectively. Levels in all samples except water were high indicating potential for adverse effects.  相似文献   
913.
Feeding dry foods supplemented with urine acidifier (D,L-methionine (Met) or ammonium chloride) decreased urinary pH and struvite activity product in clinically normal cats. As a result, the number of struvite crystals in urine was greatly reduced. Supplementation with 3% Met but not 1% Met caused decrease in the urinary concentration of sediment, which resulted from a reduction in the HCl-soluble fraction. The concentration of HCl-insoluble sediment was not affected by supplementation with the urine acidifier.  相似文献   
914.
OBJECTIVE: To determine the effect of hydroxyethyl starch (HES) on colloid oncotic pressure (pi) during fluid resuscitation of hypoproteinemic horses and to evaluate the clinical usefulness of direct and indirect methods for determination of pi before and after infusion of a synthetic colloid. DESIGN: Prospective clinical study. ANIMALS: 11 hypoproteinemic horses. PROCEDURE: Horses received IV infusions of 8 to 10 ml of a 6% solution of HES/kg (3.6 to 4.5 ml/lb) of body weight during fluid resuscitation. Blood samples were obtained for determination of plasma measured colloid oncotic pressure (pi meas) and plasma total protein and albumin (A) concentrations. Plasma globulin concentration (G) was calculated as the difference between plasma total protein and albumin concentrations. Calculated values for colloid oncotic pressure (piA + G) were determined by use of a predictive nomogram previously developed for horses. RESULTS: There was no significant difference between the means of pi meas and piA + G at the beginning of HES infusion. After HES infusion, the mean of pi meas was increased significantly from baseline for 6 hours. Mean plasma total protein and albumin concentrations and piA + G were decreased significantly from baseline for 24 hours. Differences between mean pi meas and piA + G after HES infusion were significant for 24 hours. CONCLUSIONS AND CLINICAL RELEVANCE: There was good agreement between plasma pi meas and piA + G in blood samples obtained from hypoproteinemic horses immediately before infusion of HES. Use of a predictive nomogram did not, however, account for the oncotic effect of HES. Results of comparison of pi meas to piA + G after HES infusion suggest that a significant oncotic effect was maintained for 24 hours in the study horses.  相似文献   
915.
916.
917.
Forty-five dogs with severe respiratory signs caused by idiopathic, acquired laryngeal paralysis were treated by partial laryngectomy. The predominant postoperative complications were coughing in 28 dogs and pneumonia in 15 dogs. Eight dogs required a second operation to alleviate persistent or recurrent upper airway obstruction. Results of surgery were considered excellent in 11 dogs (25%), good in 18 dogs (40%), fair in 6 dogs (13%), and poor in 10 dogs (22%). Poorer results were obtained by surgical residents than by more experienced surgeons. Death in the immediate postoperative period was related to pneumonia (8 dogs) and laryngeal collapse (1 dog). Nine dogs died later of respiratory disease. Although partial laryngectomy is effective for the treatment of laryngeal paralysis, it is not recommended because of the high incidence of postoperative complications.  相似文献   
918.
An indexing system for hygiene variables associated with egg production was developed by use of data collected from chicken flocks in southern California. The data were analyzed by factor and regression analysis. On the basis of our findings, hygiene index in relation to egg production consists of ventilation system, cooling system, manure removal, and truck movement. Flocks kept under natural ventilation produced, on the average, 2% more hen-day eggs than flocks kept under artificial ventilation. Flocks placed in houses with roof sprinklers produced 3.3% more hen-day eggs, compared with flocks placed in houses with inside foggers and pad. Flocks kept under the system of frequent removal of manure produced 2% more hen-day eggs than flocks kept under the system for which the manure was removed less frequently. Flocks kept in farms that restricted trucks collecting dead birds from entering the premises produced 3.4% more hen-day eggs than those that allowed such trucks to enter the farm.  相似文献   
919.
Ten Holstein cows averaging 120 d in lactation were arranged in replicated 5 x 5 Latin squares with 3-wk periods to evaluate the role of sulfur (S) in the dietary cation-anion balance equation. Diets were based on corn silage in Exp. 1 and sorghum silage in Exp. 2. Supplemental S and chloride (Cl) from the double sulfate of potassium and magnesium and CaCl2 were used to manipulate dietary cation-anion balance from 0 to +30 meq when expressed as meq [(Na + K)-(Cl + S)]/100 g diet DM and from +19 to +49 meq when expressed as meq [(Na + K)-Cl]/100 g diet DM. Blood pH was not affected by cation-anion balance, although both S and Cl supplementation tended to lower pH. Blood HCO3- and urine pH decreased and plasma calcium (Ca) and urinary Ca excretion increased as anion was added to the diet. Milk fat production tended to be increased by the low S supplementation. Dietary Cl and S had similar effects on acid-base status. Therefore, we suggest that S be included with Cl in the dietary cation-anion balance equation for lactating dairy cows as follows: meq [(Na + K)-(Cl + S)]/100 g diet DM. Although response of acid-base status to S and Cl was similar, as more data comparing the acidogenicity of S vs Cl become available, it may be necessary to include a modifying coefficient for S in the equation to adjust for differences between S and Cl in acid-generating potential. This coefficient may be further dependent on the dietary source of S.  相似文献   
920.
In the silver fox, as in its wild ancestor, the red fox (Vulpes vulpes L.), the annual growing phase (anagen) of guard hair follicles occupies at least four months. Severe damage to the hair coat near the end of this growing period was reported in 1985 on many ranches in New Brunswick and Nova Scotia. A histological analysis of serial sections of skin biopsies showed a marked increase in nuclear aberrations in the hair matrix of anagen guard hair follicles. These nuclear aberrations indicated that cells were undergoing apoptosis, a controlled form of cell death. Tissues from affected and unaffected foxes for histological and toxicological analysis, as well as other data, were obtained during visits to 26 ranches in 1986 and 34 ranches in 1987. Histological sections of the 1987 skin samples showed the mean percentage of nuclear aberrations in 43 unaffected foxes to be 0.08 +/- 0.01 (SEM), while that for 49 affected foxes was 0.51 +/- 0.23. The four foxes with the most severe coat damage also had the highest incidences of guard hair matrix cells with nuclear aberrations, ranging from 20 to 100 times greater than the mean for unaffected foxes. The mitotic index of the hair matrix, which normally remains fairly constant during the hair growth phase, was similar for unaffected and affected foxes (1.83 +/- 0.06 and 1.97 +/- 0.07 respectively). Although our analyses of field data have not established a specific environmental factor associated with increased nuclear aberrations, the possible involvement of toxic agents in follicle damage may warrant further investigation.  相似文献   
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