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291.
Fisheries are supposed to be for the benefit of society, producing food, providing livelihoods and enabling cultural continuity. Biological productivity goals for fish stocks operationalised through Harvest Control Rules (HCRs) are central to contemporary fisheries management. While fisheries policies often state socio-economic objectives, such as enhancing the livelihoods of coastal communities, those are rarely, if ever, incorporated into operationalised management procedures. The lack of articulation of social objectives and lack of monitoring of social outcomes around HCRs amounts to poor public policy. In this article, we explore the potential for social HCRs (sHCRs) with reference points and agreed predefined actions to make the social dimensions of fisheries explicit. sHCRs cannot cover all social dimensions, so should be considered as one tool within a broader framework of fisheries governance. Moreover, successful sHCRs would require sound deliberative and participatory processes to generate legitimate social objectives, and monitoring and evaluation of fisheries management performance against those objectives. We introduce two potential types of sHCRs, one based on allocation of catch within biological limit reference points, and one for when fishing exceeds biological limit reference points. The application of sHCRs, we argue, can foster accountability and help avoid non-transparent negotiations on size and distribution of the catch. Our proposal is a call to action for policy makers and fisheries managers to properly integrate social criteria into fisheries governance, and for both biophysical fisheries scientists and social scientists to do better in practical collaboration for methods and knowledge development to support this integration.  相似文献   
292.
Background: Pituitary tumors in dogs can be adenomas, invasive adenomas, or adenocarcinomas. In people, invasive adenomas and pituitary adenocarcinomas carry a worse prognosis than adenomas.
Hypothesis/Objective: To identify differentiating features on cross-sectional imaging in dogs with pituitary adenomas, invasive adenomas, and adenocarcinomas.
Animals: Thirty-three dogs that had computed tomography (CT) or magnetic resonance imaging (MRI) performed and a necropsy diagnosis of pituitary adenoma ( n = 20), invasive adenoma ( n = 11), or adenocarcinoma ( n = 2).
Methods: Medical records were retrospectively reviewed for signalment, history, and diagnosis. CT and MR images were reviewed for characteristics of pituitary tumors.
Results: Mean (± standard deviation) age for dogs with pituitary adenomas (10.6 ± 2.9 years) was greater than that of those with invasive adenomas (8.3 ± 2.7 years, P = .04). Eighteen out of 20 (90%) dogs with adenomas had contrast-enhancing masses. Thirteen out of 20 (65%) had homogeneous enhancement. Mean adenoma height was 1.2 ± 0.7 cm. Eight out of 20 (40%) adenomas were round and 8/20 (40%) compressed surrounding brain. Eleven out of 11 dogs (100%) with invasive adenomas had contrast-enhancing masses. Seven out of 11 (64%) masses were homogeneous. Mean invasive adenoma height was 1.8 ± 0.7 cm, which was significantly greater than adenomas ( P = .03). Mass shape varied from round to oval to irregular. Six out of 11 (55%) masses compressed surrounding brain. Clinical and imaging features were variable for 2 dogs with adenocarcinomas.
Conclusions and Clinical Relevance: Invasive adenoma should be suspected if a dog with a pituitary tumor is <7.7 years of age and has a mass >1.9 cm in vertical height. Adenocarcinomas are uncommon and metastatic lesions were not seen with imaging.  相似文献   
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294.
Adults of a phosphine-resistant strain of Sitophilus oryzae (L) were exposed to constant phosphine concentrations of 0.0035-0.9mg litre(-1) for periods of between 20 and 168h at 25 degrees C, and the effects of time and concentration on mortality were quantified. Adults were also exposed to a series of treatments lasting 48, 72 or 168 h at 25 degrees C, during which the concentration of phosphine was varied. The aim of this study was to determine whether equations from experiments using constant concentrations could be used to predict the efficacy of changing phosphine concentrations against adults of S oryzae. A probit plane without interaction, in which the logarithms of time (t) and concentration (C) were variables, described the effects of concentration and time on mortality in experiments with constant concentrations. A derived equation of the form C(n)t = k gave excellent predictions of toxicity when applied to data from changing concentration experiments. The results suggest that for resistant S oryzae adults there is nothing inherently different between constant and changing concentration regimes, and that data collected from fixed concentrations can be used to develop equations for predicting mortality in fumigations in which phosphine concentration changes. This approach could simplify the prediction of efficacy of typical fumigations in which concentrations tend to rise and then fall over a period of days.  相似文献   
295.
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis.  相似文献   
296.
This article presents the results of an Internet-based review conducted in January and February 2003 to assess the educational opportunities available in veterinary public health, epidemiology, and preventive medicine at the 27 veterinary schools in the United States. Most professional veterinary curricula are designed to train students for careers as highly qualified private practitioners, although there is an increased need for veterinary perspectives and contributions in the public health sector. The future of veterinary public health relies on the opportunities available in education to teach and encourage students to pursue a career of public service. The results of this review indicate the availability of a wide variety of required courses, electives, and post-graduate training programs to veterinary students in the United States. Veterinary students are exposed to a median of 60 hours of public health, epidemiology, and preventive medicine in required stand-alone courses in these areas. Four veterinary schools also have required rotations for senior students in public health, preventive medicine, or population medicine. Contact time for required public health, epidemiology, and preventive medicine courses ranges from 30 to 150 contact hours. Advanced training was available in these subjects at 79% of the 27 schools. Greater collaboration between veterinary schools, schools of public health, and the professional public health community will increase exposure to and opportunities in public health to all future veterinarians.  相似文献   
297.
298.
Objective: To describe a dog with Budd–Chiari‐like syndrome secondary to caudal vena cava compression from a thoracic wall chondrosarcoma. Case summary: A 9‐year‐old spayed female Shetland Sheepdog cross with a recent history of non‐productive cough developed severe abdominal distension and dyspnea. Marked ascites and enlarged hepatic veins were identified with ultrasonography. At surgery, a right thoracic wall mass was found to be compressing the caudal vena cava. Fluid analysis of the ascites revealed a modified transudate with elevated protein concentration, consistent with Budd–Chiari‐like syndrome. Clinical signs resolved following thoracotomy and complete resection of the mass. New or unique information provided: Obstruction of venous blood flow can result from compression exerted by a space‐occupying thoracic wall mass on the caudal vena cava. Clinical resolution can be achieved with return of adequate venous circulation by removal of the mass and alleviation of the external pressure.  相似文献   
299.
OBJECTIVE: To determine whether corn snakes exposed to UVB radiation have increased plasma 25-hydroxyvitamin D3 concentrations, compared with control snakes. ANIMALS: 12 corn snakes (Elaphe guttata). PROCEDURES: After an acclimation period in individual enclosures, a blood sample was collected from each snake for assessment of plasma 25-hydroxyvitamin D3 concentration. Six snakes were provided with no supplemental lighting, and 6 snakes were exposed to light from 2 full-spectrum coil bulbs. By use of a radiometer-photometer, the UVA and UVB radiation generated by the bulbs were measured in each light-treated enclosure at 3 positions at the basking surface and at 2.54 cm (1 inch) below each bulb surface; the arithmetic mean values for the 3 positions at the basking surface and each individual bulb surface were calculated immediately after the start of the study and at weekly intervals thereafter. At the end of the study (day 28), another blood sample was collected from each snake to determine plasma 25-hydroxyvitamin D3 concentration. RESULTS: Mean +/- SD plasma concentration of 25-hydroxyvitamin D3 in snakes that were provided with supplemental lighting (196 +/- 16.73 nmol/L) differed significantly from the value in control snakes (57.17 +/- 15.28 nmol/L). Mean exposure to UVA or UVB did not alter during the 4-week study period, although the amount of UVA recorded near the bulb surfaces did change significantly. CLINICAL RELEVANCE: These findings have provided important insight into the appropriate UV radiation requirements for corn snakes. Further investigation will be needed before exact husbandry requirements can be determined.  相似文献   
300.
OBJECTIVE: To evaluate correlations among measurements on radiographic and computed tomography (CT) images with articular cartilage microdamage in lax hip joints of dogs. ANIMALS: 12 adult mixed-breed hounds. PROCEDURES: Pelvic CT and radiography were performed. Hip joints were harvested following euthanasia. Orthopedic Foundation for Animals (OFA) and PennHIP radiograph reports were obtained. Norberg angle (NA) and radiographic percentage femoral head coverage (RPC) were determined. Center-edge angle (CEA), horizontal toit externe angle (HTEA), ventral acetabular sector angle (VASA), dorsal acetabular sector angle (DASA), horizontal acetabular sector angle (HASA), acetabular index (AI), and CT percentage femoral head coverage (CPC) were measured on 2-dimensional CT images. Femoral head-acetabular shelf percentage was measured on sagittal 3-dimensional CT (SCT) and transverse 3-dimensional CT (TCT) images. Light microscopy was used to score joint cartilage. Relationships of OFA confirmation and PennHIP osteoarthritis scores with radiography, CT, and cartilage variables and relationships of cartilage scores with radiography and CT measurements were evaluated with Spearman rank correlations. Pearson correlation was used for relationships of distraction index (DI) with radiography, CT, and cartilage variables. RESULTS: Significant relationships included PennHIP osteoarthritis score with cartilage score, CEA, HTEA, DASA, AI, CPC, and TCT; OFA confirmation score with cartilage score, NA, RPC, CEA, HTEA, DASA, AI, CPC, and TCT; cartilage score with NA, RPC, CEA, HTEA, DASA, HASA, AI, and TCT; and DI with cartilage score, CEA, HTEA, DASA, HASA, AI, and CPC. CONCLUSIONS AND CLINICAL RELEVANCE: CT appeared to be a valuable imaging modality for predicting cartilage microdamage in canine hip joints.  相似文献   
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