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51.
Cats with hyperthyroidism [(increased serum thyroxine (T(4))] commonly have increased serum alkaline phosphatase (ALP) activity in addition to other serum biochemical abnormalities. Serum biochemical profiles were obtained from 10 hyperthyroid cats which had increased serum ALP. Agarose gel electrophoresis of serum from these cats was performed and stained for alkaline phosphatase activity. Alkaline phosphatase activity was calculated for each of the separate bands obtained, and the results were compared to those of tissue extracts, serum from normal cats, and serum from normothyroid cats with increased serum ALP activity. The hyperthyroid cats had increased ALP activity in bands corresponding to isoenzymes originating in the liver, bone, and an unidentified tissue source.  相似文献   
52.
BACKGROUND: Obesity is the most common nutritional disease in dogs. Although weight loss by dietary caloric energy restriction is successful in experimental studies, there is limited information on success of such programs in client-owned dogs who are obese. Further, no information currently exists on the changes in body composition during weight loss in clinical cases. HYPOTHESIS: Key determinants of outcome of weight loss, including energy allocation and body composition, are influenced by both individual and weight program factors. ANIMALS: Nineteen client-owned dogs with naturally occurring obesity. METHODS: In this prospective clinical study, body composition was quantified by dual-energy X-ray absorptiometry before and after weight loss on an individually tailored program that incorporated a high-protein and moderate-fiber diet. RESULTS: Mean percentage weight loss was 18% (range, 6-29%), and mean rate of weight loss was 0.85% per week (range, 0.35-1.56%). Mean energy allocation required to achieve weight loss was 60% of maintenance energy requirement at target weight (MERTW) (range, 50-82%). Significant dietary noncompliance was reported (mean, 1.0% MERTW; range, 0.0-9.5%). The mean composition of tissue lost was 84: 15:1 (fat : lean : bone mineral content [BMC]). Lean tissue loss was positively associated with overall percentage of weight loss (Pearson correlation coefficient [Rp] = 0.591, P = .008), whereas BMC loss was greater in retrievers compared with other breeds (1.9% +/- 1.16% versus 0.8% +/- 0.44%; P = .008). CONCLUSIONS AND CLINICAL IMPORTANCE: This clinical study demonstrated body composition changes during weight loss in dogs. Conventional programs produced safe weight loss, but marked energy restriction was required and the rate of loss was slower than in experimental studies.  相似文献   
53.
A 12-yr-old, intact male squirrel (Sciurus sp.) presented with a 15 mm-by-20 mm area of alopecia and plaque-like dermal thickening over the left caudolateral thorax. Routine diagnostic tests ruled out more common conditions that result in alopecia, such as dermatophytosis and acariasis. A punch biopsy was obtained under anesthesia and submitted for histopathologic evaluation. The diagnosis of epitheliotropic lymphoma was made, and follow-up surgical excision was performed. Histopathologic features were consistent with epitheliotropic lymphoma, and immunohistochemistry confirmed a T-cell origin. There was no local recurrence, new lesions, or evidence of metastasis 10 mo after surgical excision. To our knowledge, to date, epitheliotropic lymphoma has not been described in a squirrel.  相似文献   
54.
Robust thermal dissipation sensors of variable length (3 to 30 cm) were developed to overcome limitations to the measurement of radial profiles of sap flow in large-diameter tropical trees with deep sapwood. The effective measuring length of the custom-made sensors was reduced to 1 cm at the tip of a thermally nonconducting shaft, thereby minimizing the influence of nonuniform sap flux density profiles across the sapwood. Sap flow was measured at different depths and circumferential positions in the trunks of four trees at the Parque Natural Metropolitano canopy crane site, Panama City, Republic of Panama. Sap flow was detected to a depth of 24 cm in the trunks of a 1-m-diameter Anacardium excelsum (Bertero & Balb. ex Kunth) Skeels tree and a 0.65-m-diameter Ficus insipida Willd. tree, and to depths of 7 cm in a 0.34-m-diameter Cordia alliodora (Ruiz & Pav.) Cham. trunk, and 17 cm in a 0.47-m-diameter Schefflera morototoni (Aubl.) Maguire, Steyerm. & Frodin trunk. Sap flux density was maximal in the outermost 4 cm of sapwood and declined with increasing sapwood depth. Considerable variation in sap flux density profiles was observed both within and among the trees. In S. morototoni, radial variation in sap flux density was associated with radial variation in wood properties, particularly vessel lumen area and distribution. High variability in radial and circumferential sap flux density resulted in large errors when measurements of sap flow at a single depth, or a single radial profile, were used to estimate whole-plant water use. Diurnal water use ranged from 750 kg H2O day-1 for A. excelsum to 37 kg H2O day-1 for C. alliodora.  相似文献   
55.
It has been shown that people and pets can harbour identical strains of meticillin‐resistant (MR) staphylococci when they share an environment. Veterinary dermatology practitioners are a professional group with a high incidence of exposure to animals infected by Staphylococcus spp. The objective of this study was to assess the prevalence of carriage of MR Staphylococcus aureus (MRSA), MR S. pseudintermedius (MRSP) and MR S. schleiferi (MRSS) by veterinary dermatology practice staff and their personal pets. A swab technique and selective media were used to screen 171 veterinary dermatology practice staff and their respective pets (258 dogs and 160 cats). Samples were shipped by over‐night carrier. Human subjects completed a 22‐question survey of demographic and epidemiologic data relevant to staphylococcal transmission. The 171 human‐source samples yielded six MRSA (3.5%), nine MRSP (5.3%) and four MRSS (2.3%) isolates, while 418 animal‐source samples yielded eight MRSA (1.9%) 21 MRSP (5%), and two MRSS (0.5%) isolates. Concordant strains (genetically identical by pulsed‐field gel electrophoresis) were isolated from human subjects and their respective pets in four of 171 (2.9%) households: MRSA from one person/two pets and MRSP from three people/three pets. In seven additional households (4.1%), concordant strains were isolated from only the pets: MRSA in two households and MRSP in five households. There were no demographic or epidemiologic factors statistically associated with either human or animal carriage of MR staphylococci, or with concordant carriage by person–pet or pet–pet pairs. Lack of statistical associations may reflect an underpowered study.  相似文献   
56.
The skin of the perianal region is very thin and sensitive. The carbon dioxide laser is a very effective tool for removing tumors and treating conditions of this area. It offers a "no touch" method of treatment for conditions of the perianal region. There is less bleeding, less pain, less swelling with the use of the carbon dioxide laser. The carbon dioxide laser is an effective tool for excising perianal tumors, rectal tumors, performing anal sacculectomies and treating perianal fistulas.  相似文献   
57.
For breeding programs of the tetraploid potato (Solanum tuberosum), both wild and cultivated diploid relatives are valuable sources of genetic diversity. While both types of germplasm are used in breeding programs, there are several advantages to using wild relatives. Diploid relatives are typically crossed with haploids (2n = 2x = 24) from tetraploid S. tuberosum to improve daylength adaptation. Most haploids are male sterile, so they are typically used as female parents. Cultivated diploids, such as members of the Phureja Group, produce male sterile hybrids when crossed as females to haploids; wild relatives, such as S. tarijense, often produce male fertile hybrids. Tuber yield following crosses of haploids to cultivated or wild relatives is often high. However, cultivated relatives generally produce hybrids with a high set of small tubers; hybrids from wild relatives are variable, but many are similar to cultivars in tuber size and set. While tubers of hybrids from cultivated relatives are typically rough, with deep eyes and raised internodes, those from wild relatives are often smooth. Tuber dormancy in hybrids with cultivated relatives is generally short, while that in hybrids with wild species is longer, allowing for storage over winter. Finally, resistance to several major diseases and stresses has been found in wild species and their hybrids with S. tuberosum haploids. The desirable traits in hybrids are transmitted to tetraploids via unilateral sexual polyploidization (4x × 2x or 2x × 4x crosses in which the diploid parent produces 2n gametes). Wild Solanum species are recommended for use in potato breeding programs as sources of genetic diversity that can be adapted easily following hybridization with S. tuberosum haploids.  相似文献   
58.
59.
  • 1. The Hawkesbury‐Nepean River provides potable water for 5 million people living in the Sydney basin, and water for agricultural and horticultural production that meets most of Sydney's daily needs for fresh food. Anecdotal evidence indicated that numbers of freshwater mussels have seriously declined in much of the river over recent decades.
  • 2. A field survey revealed the presence of populations of three species of mussels, Hyridella depressa, Hyridella australis and Velesunio ambiguus in the river. Higher density mussel populations were most common in catchment areas with little human modification to the channel bed or adjacent vegetation communities.
  • 3. Levels of disturbance of riparian vegetation and, to a lesser degree, land use, were identified as being strongly associated with the absence of mussels from some reaches.
  • 4. Catchment geomorphology was also shown to be relevant to the abundance, population structure and suite of mussel species present in different geomorphic reaches of the river. Absence of mussels was noted from areas where they had been recorded in previous studies. These results demonstrate that mussel species are under threat in the catchment.
  • 5. As filter feeders with the ability to remove excess nutrients and bioaccumulate toxic substances, freshwater mussels play an important role in natural remediation processes in freshwater systems.
  • 6. The decline in mussel populations in the Hawkesbury‐Nepean River highlights concerns for the overall health of the river system, and supports the need to identify the subsidiary impacts of physical habitat modification in developing both riverine and riparian management strategies.
Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
60.
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