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Triple-phase bone scintigraphy was used to evaluate tissue viability in the forelimb of a dog after gunshot injury. This technique was reliable, noninvasive, and easily performed. It was used to complement radiography by providing functional, rather than structural, assessment of tissues on the basis of regional vascular patterns. In this dog, vascular impairment caused by trauma appeared as photopenic or "cold" spots during immediate (vascular), soft tissue and bone phases of the scintigraphic study. On the basis of gross morphologic and scintigraphic findings, forelimb amputation was performed.  相似文献   
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A 5-year-old Oldenburg mare presented for poor performance, head-tossing and bucking when ridden. An abnormal respiratory noise was audible during exercise. Computed tomography (CT) revealed right laryngeal dysplasia; an absent cricothyroid articulation, abnormally shaped thyroid cartilage, underdeveloped cricopharyngeus muscle, rostral displacement of the palatopharyngeal arch and an oesophageal air column. In this case, it was unlikely that the laryngeal pathology was related to the horse's clinical signs. This case report provides a reference CT examination of laryngeal dysplasia, corroborating previous findings using magnetic resonance imaging, radiography, ultrasonography and post-mortem examination.  相似文献   
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The Clean Development Mechanism (CDM) of the Kyoto Protocol of the United Nations Framework Convention on Climate Change allows a country that emits C above agreed-upon limits to purchase C offsets from an entity that uses biological means to absorb or reduce greenhouse emissions. The CDM is currently offered for afforestation and reforestation projects, but may apply subsequently to sequestration in agricultural soils. Additionally, markets outside of the Protocol are developing for soil C sequestration.  相似文献   
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Abstract The efficacy of twice daily topical application of capsaicin (0.025%) for the management of pruritus in dogs with atopic dermatitis (AD) was evaluated in double-blinded, placebo-controlled study. Twelve dogs with AD were randomly assigned to either 0.025% capsaicin or vehicle lotion applied twice daily for 6 weeks. After a 4-week wash-out period, treatments were switched. Significant improvement was reported by owners ( P  = 0.0006), but not by investigators. Owners noted temporary worsening of pruritus after the first week of capsaicin therapy. Overall capsaicin was well tolerated. Substance P (SP) concentrations in the skin did not correlate with the severity of the pruritus and did not change significantly over time and between treatments. Lesional skin had less SP than nonlesional skin ( P  = 0.03). These observations suggest that topical capsaicin should be further evaluated as an adjunctive antipruritic agent in dogs with AD.  相似文献   
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Promoting patchy recruitment of shade tolerant tree species into the midstory is an important step in developing structural diversity in second-growth stands. Variable-density thinning (VDT) has been proposed as a strategy for accelerating structural diversity, as its combination of within-stand treatments (harvest gaps, thinning, and non-harvested skips) should create variable overstory and understory conditions. Here we report on western hemlock (Tsuga heterophylla (Raf.) Sarg.) seedling and sapling densities in five mixed-conifer stands and Sitka spruce (Picea sitchensis (Bong.) Carr.) seedling and sapling densities in two stands in western Washington at 3,7, 10, and 16–17 years after VDT. Additionally, we report on western hemlock advance regeneration growth and survival in two stands over 14 years. Western hemlock seedling density was highest in the thinned treatment but only significantly so in Year 10. In contrast, the gaps contained significantly more western hemlock saplings in Years 7 and 10 and significantly greater growth of western hemlock advance regeneration through Year 10. Skips embedded within the VDT did not differ significantly from unharvested reserves in terms of seedling or sapling densities of either species. Sitka spruce seedling density was highest in the gap and thinned treatments, but saplings were uncommon in all treatments. Collectively, these results indicate that our variant of VDT promoted patchy, midstory recruitment of western hemlock but failed to recruit Sitka spruce saplings in either stand where it established. Consequently, more intensive variants of VDT may be required to promote midstory recruitment of species less tolerant of shade than western hemlock.

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Two experiments were conducted to evaluate the effect of prenatal testosterone treatment in combination with postnatal steroid implantation (Exp. 1) and to assess the effect of time of prenatal testosterone treatment in conjunction with postnatal steroid implantation (Exp. 2) on animal performance and carcass characteristics. In Exp. 1, seventy-six pregnant cows were assigned randomly to a control group or implanted with testosterone propionate (TP) silastic implants between d 40 and 80 of gestation. Half the heifer calves were selected randomly to be implanted with 200 mg TP plus 20 mg estradiol benzoate (EB); the other half of the steer calves were implanted with 200 mg progesterone plus 20 mg EB on d 1 and 85 of the feedlot trial. Daily gain of heifers was increased 10.4% (P less than .08) due to prenatal testosterone treatment (P) and 16.4% (P less than .05) by postnatal steroid implantation (I). Feed efficiency was 12.9% greater (P less than .05) due to P and 9.5% greater (P less than .05) due to I. Prenatal testosterone treatment decreased (P less than .05) kidney, pelvic and heart fat and final yield grade but increased (P less than .05) ribeye area of heifers. Heifers had greater (P less than .07) liver weights per unit of carcass weight due to P. In Exp. 2, one hundred seventy-four pregnant cows were assigned randomly to a control group or implanted with TP silastic implants on d 42, 63, 84 or 105 of gestation. Half the heifer and steer calves were selected randomly to be implanted on d 1 and 112 of the feedlot trial. Time of P caused a quadratic effect (P less than .08) on birth weight of heifers. There was a quadratic effect (P less than .05) of time of P on daily gain and final weight per day of age of heifers. Feed efficiency of heifers was improved (P less than .05) due to P. Postnatal steroid implantation increased (P less than .05) daily gain and feed efficiency of heifers by 9.6% and 8.6%, respectively. No changes were observed in growth performance of steers due to P. Results from these two trials suggest that the combination of prenatal testosterone treatment and postnatal testosterone and estradiol implantation produced an additive improvement of daily gain, feed efficiency and carcass merit of heifers.  相似文献   
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