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51.
    
BACKGROUND: Multi-frequency bioelectrical impedance analysis (MF-BIA) has been used to evaluate extracellular fluid volume (ECFV), but not fluid fluxes associated with fluid or furosemide administration in horses. If able to detect acute changes in ECFV, MF-BIA would be useful in monitoring fluid therapy in horses. HYPOTHESIS: The purpose of this study was to evaluate the ability of MF-BIA to detect acute fluid compartment changes in horses. We hypothesized that MF-BIA would detect clinically relevant (10-20%) changes in ECFV. ANIMALS: Six healthy mares were used in the study. METHODS: This is an original experimental study. Mares were studied in 3 experiments: (1) crystalloid expansion of normally hydrated subjects, (2) furosemide-induced dehydration followed by crystalloid administration, and (3) acute blood loss followed by readministration of lost blood. MF-BIA measurements were made before, during, and after each fluid shift and compared to known changes in volume calculated based on the intravenous fluids that were administered in addition to urinary fluid losses. Mean errors between MF-BIA estimated change and known volume change were compared using nonparametric analysis of variance. Estimated ECFV pre- and post-fluid administration similarly were compared. The level of statistical significance was set at P < .05. RESULTS: Results of the study revealed a statistically significant change in ECFV and total body water during crystalloid expansion and dehydration. Statistically significant changes were not observed during blood loss and administration. Mean errors between MF-BIA results and measured net changes were small. CONCLUSIONS AND CLINICAL IMPORTANCE: MF-BIA represents a practical and accurate means of assessing acute fluid changes during dehydration and expansion of ECFV using isotonic crystalloids with potential clinical applications in equine critical care.  相似文献   
52.
    
The ability of commercially available Haemophilus somnus bacterins to elicit an immunoglobulin E (IgE) response was examined in healthy calves using enzyme-linked immunosorbent assay (ELISA) and western blotting techniques. Thirty five calves were utilized in this study. Calves in Group 1 (n=7) did not receive any H. somnus vaccination and served as negative controls. Calves in each of Groups 2-5 (n=7 each) were vaccinated on days 0 (primary) and 14 (booster) with one of four commercially available H. somnus bacterins. Sera were harvested on days 0 and 14 and at weekly intervals for a total of 45 days. Sera were tested for the presence of IgE antibodies using a bovine IgE-specific ELISA.Low levels of H. somnus-specific IgE were detected by ELISA in all animals prior to the initiation of the study. All bacterins induced IgE levels that were significantly higher than control levels. Two bacterins elicited higher IgE levels at all time points. Sera were adsorbed against washed whole cells of either Salmonella typhimurium, P. multocida, or H. somnus or extracts of H. somnus. ELISA absorbance values were significantly decreased by adsorption with washed whole cells or extracts of H. somnus, whereas adsorption with other gram-negative bacteria only minimally decreased ELISA absorbance values. These results indicate that commercially available H. somnus bacterins can induce IgE antibody as early as 14 days post-vaccination. This IgE can be detected 45 days after the primary vaccination. Results also indicate that H. somnus-specific IgE antibodies can be found in serum of some cattle, possibly induced by existing or previous sensitization.  相似文献   
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A 23-year-old Miniature Horse gelding was presented to the Lloyd Veterinary Medical Center with a 3-week history of decreased appetite, lethargy and mild intermittent colic. A complete blood count revealed leucopenia, characterised by neutropenia and lymphopenia, as well as anaemia, thrombocytopenia and hyperproteinaemia whereas hypertriglyceridaemia was noted on serum biochemistry profile. Bone marrow evaluation was nondiagnostic and the horse was negative for antiplatelet antibody testing, Coombs test, equine infectious anaemia virus and Anaplasma phagocytophilum. The horse was hospitalised for 36 days and received supportive care, antibiotics, corticosteroids, dextrose-containing fluids and a whole blood transfusion. Following initial improvement and stabilisation, the horse became severely anaemic and acutely recumbent on Day 36 and was subjected to euthanasia. Post-mortem examination provided a diagnosis of hypersplenism with a markedly enlarged spleen along with histiocytic phagocytosis of erythrocytes and platelets. Examination of bone marrow showed appropriate erythroid hyperplasia and no evidence of myelopthisis or neoplasia. This report describes the first presumptive case of primary hypersplenism in an equid as a cause of pancytopenia.  相似文献   
54.
    
Vineyard management practices to enhance soil conservation principally focus on increasing carbon (C) input, whereas mitigating impacts of disturbance through reduced tillage has been rarely considered. Furthermore, information is lacking on the effects of soil management practices adopted in the under-vine zone on soil conservation. In this work, we evaluated the long-term effects (22 years) of alley with a sown cover crop and no-tillage (S + NT), alley with a sown cover crop and tillage (S + T), and under-vine zone with no vegetation and tillage (UV) on soil organic matter (SOM), microbial activity, aggregate stability, and their mutual interactions in a California vineyard in USA. Vegetation biomass, microbial biomass and activity, organic C and nitrogen (N) pools, and SOM size fractionation and aggregate stability were analysed. Soil characteristics only partially reflected the differences in vegetation biomass input. Organic C and N pools and microbial biomass/activity in S + NT were higher than those in S + T, while the values in UV were intermediate between the other two treatments. Furthermore, S + NT also exhibited higher particulate organic matter C in soil. No differences were found in POM C between S + T and UV, but the POM fraction in S + T was characterized by fresher material. Aggregate stability was decreased in the order: S + NT > UV > S + T. Tillage, even if shallow and performed infrequently, had a negative effect on organic C and N pools and aggregate stability. Consequently, the combination of a sown cover crop and reduced tillage still limited SOM accumulation and reduced aggregate stability in the surface soil layer of vineyards, suggesting relatively lower resistance of soils to erosion compared to no-till systems.  相似文献   
55.
Bacterial colonization of the developing light organ of the squid Euprymna scolopes is shown to be highly specific, with the establishment of a successful association resulting only when the juvenile host is exposed to seawater containing one of a subset of Vibrio fischeri strains. Before a symbiotic infection the organ has elaborate epithelial structures covered with cilia and microvilli that are involved in the transfer of bacteria to the incipient symbiotic tissue. These structures regressed within days following infection; however, they were retained in uninfected animals, suggesting that the initiation of symbiosis influences, and is perhaps a prerequisite for, the normal developmental program of the juvenile host.  相似文献   
56.
Growth and survival of hatchery‐bred Asian catfish, Clarias macrocephalus (Günther), fry reared at different stocking densities in net cages suspended in tanks and ponds were measured. The stocking densities used were 285, 571 and 1143 fry m?3 in tanks and 114, 228 and 457 fry m?3 in ponds. Fish were fed a formulated diet throughout the 28‐day rearing period. Generally, fish reared in cages in ponds grew faster, with a specific growth rate (SGR) range of 10.3–14.6% day?1, than those in cages suspended in tanks (SGR range 9–11.3% day?1). This could be attributed to the presence of natural zooplankton (copepods and cladocerans) in the pond throughout the culture period, which served as additional food sources for catfish juveniles. In both scenarios, the fish reared at lower densities had significantly higher SGR than fish reared at higher densities. In the pond, the SGR of fish held at 228 and 457 m?3 were similar to each other but were significantly lower than those of fish held at 114 m?3. The zooplankton in ponds consisted mostly of copepods and cladocerans, in contrast to tanks, in which rotifers were more predominant. Per cent survival ranged from 85% to 89% in tanks and from 78% to 87% in ponds and did not differ significantly among stocking densities and between rearing systems. In conclusion, catfish nursery in cages suspended in tanks and ponds is density dependent. Catfish fry reared at 285 m?3 in tanks and at 114 m?3 in ponds had significantly faster growth rates than fish reared at higher densities. However, the desired fingerling size of 3–4 cm total length for stocking in grow‐out culture can still be attained at stocking densities of 457 m?3 in nursery pond and 571 m?3 in tanks.  相似文献   
57.
Fifty-one coagulase-positive staphylococcal isolates from canine urinary calculi or from the urine of dogs with documented urolithiasis, and 17 coagulase-positive staphylococcal isolates from human beings and cattle were identified by a commercially available tray micromethod, as well as by conventional methods. Canine isolates had previously been classified as Staphylococcus aureus on the basis of a positive tube coagulase test. After 5 hours' incubation, the tray method identified all 51 canine urolithiasis isolates as S intermedius, rather than S aureus. All human and bovine isolates were identified as S aureus. Conventional methods supported these findings.  相似文献   
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59.
Introduction: Hemoglobin A1C (HbA1c) reflects patient’s glycemic status over the previous 3 months. Previous studies have reported that iron deficiency may elevate A1C concentrations, independent of glycemia. This study is aimed to analyze the effect of iron deficiency anemia on HbA1c levels in diabetic population having plasma glucose levels in control. Methods: Totally, 120 diabetic, iron-deficient anemic individuals (70 females and 50 males) having controlled plasma glucose levels with same number of iron-sufficient non-anemic individuals were streamlined for the study. Their data of HbA1c (Bio-Rad D-10 HPLC analyzer), ferritin (cobas e411 ECLIA hormone analyzer), fasting plasma glucose (FPG, Roche Hitachi P800/917 chemistry analyzer), hemoglobin (Beckman Coulter LH780), peripheral smear examination, red cell indices, and medical history were recorded. Statistical analysis was carried out by student’s t-test, Chi-square test, and Pearson’s coefficient of regression. Results: We found elevated HbA1c (6.8 ± 1.4%) in iron-deficient individuals as compared to controls, and elevation was more in women (7.02 ± 1.58%). On further classification on the basis of FPG levels, A1C was elevated more in group having fasting glucose levels between 100-126 mg/dl (7.33 ± 1.55%) compared to the those with normal plasma glucose levels (<100 mg/dl). No significant correlation was found between HbA1c and ferritin and hemoglobin. Conclusion: This study found a positive correlation between iron deficiency anemia and increased A1C levels, especially in the controlled diabetic women and individuals having FPG between 100-126 mg/dl. Hence, before altering the treatment regimen for diabetic patient, presence of iron deficiency anemia should be considered. Key Words: Iron deficiency anemia, Hemoglobin A1C (HbA1c), Diabetes  相似文献   
60.
    
OBJECTIVE: To describe surgical treatment of tricuspid valve stenosis using the Fontan procedure in a young dog. STUDY DESIGN: Case report. SAMPLE POPULATION: One client-owned dog RESULTS: A six month old female Labrador retriever was diagnosed with tricuspid obstruction. The dog had a displaced tricuspid valve and small right ventricle and had progressed to right-sided (backward) cardiac failure. A Fontan procedure (connection of the right atrium to the pulmonary artery with a prosthetic conduit) was performed. Within three days the right atrial pressure had dropped from a preoperative value of 33 mm Hg to 8 mm Hg and the ascites was significantly reduced. The dog died suddenly two months after surgery. Postmortem examination of the heart showed a greatly enlarged right atrium and hypoplastic right ventricle. The tricuspid valve leaflets were fused and displaced ventrally leaving an opening measuring 3x5 mm between the chambers. The conduit was intact with no evidence of leakage or thrombosis. CONCLUSIONS: Palliation of tricuspid stenosis using the Fontan procedure can be performed in dogs. Sudden death may occur and is most likely because of cardiac arrythmias.  相似文献   
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