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241.
The mechanisms contributing to BW gain following ovariohysterectomy in domestic cats are poorly understood. Moreover, the effects of food restriction to maintain BW following spaying have been poorly studied. Thus, our primary objective was to determine the effects of spaying and food restriction to maintain BW on adipose and skeletal muscle mRNA abundance and activity levels in cats. After a 4-wk baseline period (wk 0), 8 adult (approximately 1.5 yr old) domestic shorthair cats were spayed and fed to maintain BW for 12 wk. After 12 wk, cats were fed ad libitum for an additional 12 wk. Body composition was determined, activity levels were measured, and adipose and muscle biopsies were collected at wk 0, 12, and 24. Fasting blood samples were collected at wk 0, 6, 12, 18, and 24. To maintain BW post-spay, food intake was decreased (P < 0.05) by 30%. During this phase, mRNA abundance of adipose tissue lipoprotein lipase and leptin was decreased (P < 0.05), representing only 52 and 23% of baseline expression, respectively. Interleukin-6 mRNA, however, was increased (P < 0.05) 2-fold. Physical activity was decreased (P < 0.05) by wk 12, most dramatically during the dark period (approximately 20% of baseline activity). During ad libitum feeding (wk 12 to 24), food intake, BW, body fat percentage, and total fat mass were greatly increased (P < 0.05). Compared with wk 0, circulating leptin concentrations tended to increase (P < 0.10) by wk 18 and 24 (4.45 vs. 10.02 and 9.14 ng/mL, respectively), whereas glucose (91 vs. 162 mg/dL) and triacylglyceride (30 vs. 48 mg/dL) concentrations were increased (P < 0.05) by wk 24. Adipose tissue lipoprotein lipase, hormone sensitive lipase, and adiponectin mRNA were decreased (P < 0.05) at wk 24. Adipose interleukin-6 mRNA was increased (P < 0.05) at 24 wk. Physical activity was further decreased (P < 0.05) by wk 24, during the light (60% of baseline) and dark (33% of baseline) periods. In summary, spaying and food restriction affect physical activity levels and several genes associated with lipid metabolism (decreased lipoprotein lipase), food intake (decreased leptin expression), and insulin insensitivity (increased interleukin-6). By identifying these changes, targets for nutritional intervention or lifestyle management have been identified that may curb the risk of obesity and related disorders in spayed cats.  相似文献   
242.
Objective To determine the usefulness and clinical outcome of a combined procedure of superficial keratectomy and cryosurgery as a treatment for limbal neoplasms in horses. Study design Retrospective study. Animals Thirteen horses with 14 limbal tumors. Methods Medical records of all patients with limbal tumors, referred to the Department of Equine Sciences of Utrecht University between 1995 and 2002, were retrieved. Patient data were analyzed with respect to signalment, tumor surface area and histologic diagnosis. Surgery, performed under general anesthesia, included surgical debulking of the tumor followed by cryosurgery. Long‐term follow‐up information was obtained by re‐evaluation in the clinic, by the referring veterinarian, and/or by telephone enquiry. Results Therapy was successful in 9 out of 14 eyes after the first attempt (64%); one eye needed retreatment (7%), and four eyes were eventually enucleated (29%). The mean follow‐up period was 4.8 years. The initial surface area of the tumor significantly influenced outcome (P < 0.01). Squamous cell carcinoma was the most predominant tumor type (79%). Haflinger horses accounted for 69% of the cases whereas their occurrence in the overall hospital population is approximately 5%. Conclusions and clinical relevance The described technique of superficial keratectomy and cryosurgery is a simple procedure for the treatment of limbal tumors in equine patients that does not require sophisticated equipment. Nor is it tampered by legal restriction, and appears to be effective in tumors with a small surface area (< 2 cm2). Haflinger horses seem to be predisposed for the development of ocular squamous cell carcinoma.  相似文献   
243.
The purpose of this study was to assess pre-matriculation academic and demographic data to identify risk factors for academic difficulty and failure to graduate among veterinary students. Admissions data were compiled for 1,098 students admitted to veterinary college between 1989 and 2000 inclusive. Students were classified by (a) academic success, consisting of students who completed veterinary school within four years in the top 90% of the class or (b) academic difficulty, including students dismissed for academic reasons, students who experienced academic delay, and students who graduated with a cumulative GPA in the 10th percentile of their class. Of 1,098 admitted students, 930 (84.7%) completed veterinary school within four years in the top 90% of their class. Among students with academic difficulty, 94 (8.6%) completed veterinary school in four years in the 10th percentile, 44 (4%) experienced academic delay, and 30 (2.7%) were dismissed. Academic difficulty was associated with a low prerequisite GPA, a low GRE score, poor undergraduate institutional selectivity, and older age (> or =35 years). Students who attended three-or-more undergraduate institutions or two-year colleges prior to attending a four year institution were 1.9 times more likely to experience academic difficulty and 3.87 times more likely to fail to graduate than students who attended a four-year institution (major or small) to complete their prerequisites. These study findings may assist with early identification of students at greater risk of experiencing academic difficulty and support the consideration of cognitive selection criteria (GRE and GPA) and undergraduate institutional experience during the admissions process.  相似文献   
244.
ABSTRACT Sclerotia of Sclerotinia sclerotiorum are pigmented, multihyphal structures that play a central role in the life and infection cycles of this pathogen. Sclerotial formation has been shown to be affected by increased intracellular cAMP levels. Cyclic AMP (cAMP) is a key modulator of cAMP-dependent protein kinase A (PKA) and the latter may prove to play a significant role in sclerotial development. Therefore, we monitored changes in relative PKA activity levels during sclerotial development. To do so, we first developed conditions for near-synchronous sclerotial development in culture, based on hyphal maceration and filtering. Relative PKA activity levels increased during the white-sclerotium stage in the wild-type strain, while low levels were maintained in nonsclerotium-producing mutants. Furthermore, applying caffeine, an inducer of PKA activity, resulted in increased relative PKA activity levels and was correlated with the formation of sclerotial initial-like aggregates in cultures of the non-sclerotium-producing mutants. In addition, low PKA activities were found in an antisense smk1 strain, which exhibits low extracellular-signal-regulated kinase (ERK)-type mitogen-activated protein kinase (MAPK) activity, and does not produce sclerotia. The changes in PKA activity, as well as the abundance of phosphorylated MAPKs (ERK-like as well as p38-like) that accompany sclerotial development in a distinct developmental phase manner represent a potential target for antifungal intervention.  相似文献   
245.
Dairy cattle rearing techniques have evolved, and milking has moved from stalls to specialized premises. A survey was carried out on a representative sample of dairy farms in central Italy to investigate workers' safety in milking premises. Results indicated acceptable sound level and microclimatic conditions, whereas repetitive motion of the upper limbs should be carefully monitored for the possible effects it can induce on the milkers, who were devoid of adequate personal protective equipment (PPE). Floor antislipping characteristics represented a major deficiency in the building material, in spite of its strength and durability.  相似文献   
246.
Dall SR 《Science (New York, N.Y.)》2005,308(5720):353-6; author reply 353-6
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OBJECTIVE: To determine the prevalence of pedunculated lipomas and identify risk factors affecting postoperative complications and survival in horses at a veterinary teaching hospital undergoing surgery for colic caused by pedunculated lipomas. DESIGN: Retrospective study. ANIMALS: 102 horses with a diagnosis of pedunculated lipoma. PROCEDURE: Age, breed, weight, and sex of horses with pedunculated lipomas were compared with the total equine hospital population and the population of horses admitted for abdominal surgery during the same period. Follow-up information was obtained by reevaluation or contact with owners via telephone or written request. RESULTS: Prevalence of pedunculated lipomas as a reason for abdominal surgery in horses, compared with the population of horses with and without lipomas admitted for abdominal surgery, was 10%. Castrated male Saddlebred and Arabian horses > 14 years old were identified as being at risk for developing pedunculated lipomas. Postoperative complications were detected in 72% of horses with pedunculated lipomas. Variables associated with low survival rates included surgery before 1992, heart rate > 80 beats/min, abnormal color of abdominal fluid, pale mucous membranes, surgery requiring intestinal resection, and inability to attain a mean arterial pressure > or = 100 mm Hg. Horses undergoing surgery from 1992 to 1996, weighing < 409 kg (900 lb), or requiring jejunojejunal anastomosis had a high survival rate. CONCLUSIONS AND CLINICAL RELEVANCE: Although many of the variables reflected the health of the horse at the time of surgery, results may help veterinarians recognize risk factors associated with development of pedunculated lipomas and better predict the outcome of horses undergoing surgery for colic caused by pedunculated lipomas.  相似文献   
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