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91.
PETER A. GROOTHUIS 《Growth and change》2005,36(4):551-564
ABSTRACT Benefit transfer has become increasingly important for policy researchers as a low‐cost approach for assigning benefits to environmental amenities. To gain insights on how to best perform benefit transfer, this study analyzes estimates from both the travel cost (TC) and contingent valuation (CV) methods. The analysis compared the point estimate approach with the benefit function approach for transferring economic benefits between a study site and a policy site. Data from the 1996 National Survey of Fishing, Hunting, and Wildlife‐Associated Recreation for deer hunting was used to provide both the CV willingness‐to‐pay and the TC consumer surplus estimates. The study found that when focusing on a nonsite‐specific activity such as deer hunting, benefits transferred fairly well, with the average error being slightly less than 30 percent for CV estimates and just under 35 percent for TC estimates. In addition, the empirical results suggest that the more precise benefit function approach provide some improvement to the more general point estimate approach, with the CV methods showing moderate gains while the TC method showing only minimal gains. The study also found that the closer the distance between the policy and research sites was, the more the precision of the benefit transfer increased. 相似文献
92.
B. DUNCAN X. LASCELLES BSc BVSc PhD MRCVS CertVA CertSAS PETER J. CRIPPS BVSc PhD MRCVS ALAN JONES BSc AVRIL E. WATERMAN-PEARSON BVSc PhD FRCVS FRCA DVA Diplomate ECVA 《Veterinary surgery : VS》1998,27(6):568-582
Objective —To determine what effect the timing of carprofen administration has on the severity of postoperative pain in dogs undergoing ovariohysterectomy and to investigate the pharmacokinetics of carprofen under these conditions. Study Design —A prospective, randomized, double-blind, clinical trial. Animals —Sixty-two adult bitches weighing between 10 and 25 kgs, undergoing elective ovariohysterectomy. Methods —Examinations were performed for 20 hours postoperatively using subjective visual assessment scoring systems (DIVAS) and objective mechanical nociceptive threshold measurements. Forty dogs were assigned to one of three groups: (1) preoperative carprofen; (2) postoperative carprofen; and (3) no analgesics (saline injections). The dose of carprofen was 4.0 mg/kg subcutaneously. In another 22 bitches, the pharmacokinetics of carprofen given preoperatively or postoperatively at the same dose were examined. Results —The dogs given carprofen preoperatively had lower pain scores than the other groups, significantly so at 2 hours postextubation (P < .01 and P < .05, Kruskal-Wallis and post hoc Dunn's). Mechanical pain thresholds measured at the distal tibia showed the development of hyperalgesia at 12 and 20 hours postextubation; this was prevented by both the preoperative (P < .05 at 12 and 20 hours, Kruskal-Wallis) and postoperative (P <.05 at 20 hours, Kruskal-Wallis) administration of carprofen. Mechanical pain threshold testing at the wound showed a significant analgesic effect of carprofen. Plasma concentrations of carprofen were not directly related to analgesia; maximum plasma concentration, the area under the curve to the last data point, and area under the first moment curve up to the last data point were all significantly higher in the dogs given carprofen postoperatively (P < .05, Mann-Whitney). Conclusion—Preoperative administration of carprofen has a greater analgesic effect than postoperative administration in the early postoperative period in dogs undergoing ovariohysterectomy. Plasma levels of carprofen are not related to the degree of analgesia achieved. Clinical Relevance—Carprofen provides effective analgesia after canine ovariohysterectomy. The timing of analgesic administration is important to optimize the control of postoperative pain. 相似文献
93.
KRYSTINA STADLER SUSAN HARTMAN JODI MATHESON ROBERT O'BRIEN 《Veterinary radiology & ultrasound》2011,52(4):377-384
Seventeen dogs with clinical signs attributable to nonneoplastic obstruction of the larynx, trachea, or large bronchi underwent computed tomography (CT) imaging. In 16 of the 17 dogs, CT was performed without general anesthesia using a positioning device. Fifteen of these 16 dogs were imaged without sedation or general anesthesia. Three‐dimensional (3D) internal rendering was performed on each image set based on lesion localization determined by routine image planes. Visual laryngeal examination, endoscopy, video fluoroscopy, and necropsy were used for achieving the cause of the upper airway obstruction. The CT and 3D internal rendering accurately indicated the presence and cause of upper airway obstruction in all dogs. CT findings indicative of laryngeal paralysis included failure to abduct the arytenoid cartilages, narrowed rima glottis, and air‐filled laryngeal ventricles. Laryngeal collapse findings depended on the grade of collapse and included everted laryngeal saccules, collapse of the cuneiform processes and corniculate processes, and narrowed rima glottis. Trachea abnormalities included hypoplasia, stenosis, or collapse syndrome. The CT findings in tracheal hypoplasia consisted of a severely narrowed lumen throughout the entire length. Tracheal stenosis was represented by a circumferential decrease in tracheal lumen size limited to one region. Tracheal collapse syndrome was diagnosed by severe asymmetric narrowing. Lobar bronchi collapse appeared in CT images as a narrowed asymmetric lumen diameter. CT imaging of unanesthetized dogs with upper airway obstruction compares favorably with traditional definitive diagnostic methods. 相似文献
94.
The temporal pattern of cod landings in the inshore trap fishery off the east coast of Newfoundland and Labrador is examined in this study. Unlike previous studies which have been broad scale or of a localized nature, this analysis looks at variations within fishing seasons and among fishing areas in trap landings. A significant relationship between water temperature and the weekly pattern is demonstrated. Significant spatial patterns in weekly landings are described and related to longshore differences in the seasonal variation in temperature. 相似文献
95.
Within the context of economic and social change in rural Australia, this paper identifies four structural dimensions of non‐metropolitan communities that are shown to influence a range of areal and socio‐demographic characteristics. The analysis shows that such influence is essentially maintained whether the social catchments forming the database are subdivided by State or by an equivalent number of landscape types. Also, although the dimensions influence both the urban and dispersed elements of the communities, the strength of the relationships is substantially greater if those elements are considered as a symbiotic whole. Throughout, net rural local density (as opposed to gross density) is shown to be a consistently important dimension of rural communities in relatively sparsely settled lands such as those of south‐eastern Australia, supported by the important subsidiary influence of relative settlement dispersal and town size. The paper concludes with a discussion of the processes involved in the impact of those structural dimensions upon rural society. 相似文献
96.
Abstract— Generalized congenital hypotrichosis is reported in a female Rottweiler. This is only the second report of this genodermatosis in a female dog. The dog was predominately hairless except for bilaterally symmetric tufts of hair on the head, dorsal midline and umbilical region. Most skin biopsy sections revealed a total lack of epidermal appendages representing a complete failure of follicular development. Occasionally, small rudimentary follicular structures were subtended by melanophages and vertically oriented collagen suggesting the possibility of previously more extensive development followed by subsequent involution. According to a new classification scheme for ectodermal dysplasia proposed by Dr Carol Foil, this dog would be classified as 1–4 defect, cogenital hypotrichosis. Résumé— Une hypotrischose congénitale généralisée chez une chienne Rotweiler est rapportée. Il s'agit du second cas de cette génodermatose décrit chez une chienne. Le chien était nu exception faite de touffe de poils sur les flancs et la tête, la ligne du dos et la region ombilicale. La plupart des biopsies ont révélé une absence totale d'annexe et de développment folliculaire. Parfois quelques structures folliculaires rudimentaires étaient subtentés par la présence de mélanophages et une orientation verticale des fibres de collagène. En suivant la nouvelle classification des dysplasies ectodermiques proposée par le Dr Carol Foil, cet animal a été classé en hypotrychose congénitale de défaut 1–4. Resumen En éste artículo se describe un caso de hipotricosis congénita de tipo generalizado en una hembra de la raza Rottweiler. Éste es el segundo caso de genodermatosis reportado en una perra. Éste animal padecía de una pérdida de pelo general exceptuando algunas mechas aisladas en la cabeza, línea media dorsal y región umbilical, de una manera bilateral y simétrica. La mayoría de las biopsias cutáneas revelaron una falta total de apéndices cutáneos, lo cual representaba una fallo completo en en desarrollo del folículo. De manera espóradica, se observaron estructuras foliculares rudimentarias ínvadidas de melanófagos y con fibras de colágeno orientadas verticalmente sugiriendo la posibilidad de desarrollo previo mas extensivo seguido de posterior involución. De acuerdo con la nueva clasificación de displasia ectodérmica propuesta por Foil, éste animal sería clasificado con un defecto de 1–4 de hipotricosis congenital. 相似文献
97.
98.
Atlantoaxial stability was evaluated in 12 surgically stabilized dogs and 6 control dogs after odontoidectomy and dorsal atlantoaxial ligament separation. The atlantoaxial instabilities were stabilized with transarticular pins from a ventral approach. Cancellous bone grafts harvested from the proximal humerus were used to promote joint fusion. Good joint stability, alignment, and early fusion were documented clinically, radiographically, and histopathologically in stabilized dogs. Because of our consistent results despite variable pin angles, we recommend this technique for use in dogs with atlantoaxial instability requiring surgical stabilization. 相似文献
99.
The Effect of Drying Quercus robur Acorns to Different Moisture Contents, followed by Storage, either with or without Imbibition 总被引:1,自引:0,他引:1
Freshly harvested Quercus robur acorns were spread out, twodeep, in trays, and dried/stored (at +2°C over the courseof 28 weeks) to either 45, 40, 35, 30 or 25 per cent moisturecontent (fresh weight basis). Drying/storage significantly reducedthe germination percentage (P< 0.01). The acorns at eachmoisture content were then either soaked or notsoaked, before immediate germination; or returned tothe same cold store at +2°C, this time in loosely tied polythenebags. Soaking raised the acorns moisture content (M.C.), andalso brought about a significant increase in germination capacity(P<0.01). Regardless of the moisture content immediatelybefore soaking, "soaked" acorns in loosely tied polythene bagsstored better than unsoaked acorns. All baggedacorns (whether soaked or unsoaked)stored better than acorns dried/stored in open trays. 相似文献
100.