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New Forests - Arbuscular mycorrhizal (AM) fungi are hypothesized to assist growth of northern white-cedar in acid peatlands, yet there is little direct evidence that they can provide sufficient...  相似文献   
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The beneficial uses or functions of wildlife are numerous. In agriculture these include not only the cropping of species growing in the wild but also their potential for future cultivation and role in such processes as crop pollination and biological control of pests. Wild animals are used in medicine for essential research; wild plants provide a source of drugs, and wild places can help to relieve the tension and stress associated with modern living. Wildlife is also a sensitive indicator of environmental change. Furthermore, research and education in the environmental sciences rely on the conservation of natural and semi-natural areas. These areas and the species which inhabit them have considerable aesthetic value and have inspired many great works of art. Finally, there is a moral argument that all species have the right to exist, and that the options made possible by the presence of wildlife should be left for future generations to use. Each of these functions is discussed in detail.Sixteen components should be taken into consideration when evaluating an area for wildlife conservation. A possible approach to weighting these components is outlined.  相似文献   
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Amputation and Cisplatin for Treatment of Canine Osteosarcoma   总被引:2,自引:0,他引:2  
Seventy-one dogs with histologically confirmed appendicular osteosarcoma were evaluated. Seventeen dogs were treated with amputation and two postoperative [corrected] doses of IV cisplatin given 21 days apart (group 1). Nineteen dogs were treated with IV cisplatin 21 days before amputation, with a second dose given immediately after amputation (group 2). Thirty-five dogs were treated by amputation of the affected limb with no chemotherapy (group 3). The median disease-free interval for group 1 was 226 days, and 177 days for group 2. This was not significantly different. The median survival time was 262 days for group 1, 282 days for group 2 and 119 days for group 3. Group 1 and 2 dogs had survival times that were significantly longer than for dogs in group 3. Two IV courses of cisplatin given before or after amputation appears to improve the survival of dogs with osteosarcoma.  相似文献   
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Two dogs with signs of forebrain disease had hypodense lesions on computed tomography evaluation. Magnetic resonance imaging of the first dog showed a hypointense lesion on the T1-weighted scan and a hyperintense lesion on T2-weighted scanning. At surgery, both dogs had a primary cystic intracranial lesion, and the abnormal tissue adjacent to the cyst had histological features of meningiorna. Each dog underwent whole brain irradiation after surgery, and 1 dog lived for 3 years after treatment. While uncommon, meningioma should be considered as a differential diagnosis in dogs with cystic intracranial lesions. J Vet Intern Med 1996;10:72–75. Copyright © 1996 by the American College of Veterinary Internal Medicine .  相似文献   
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RADIOTHERAPY OF CANINE NON-TONSILLAR SQUAMOUS CELL CARCINOMA   总被引:1,自引:0,他引:1  
The records of 14 dogs treated with megavoltage radiation for non-tonsillar oral squamous cell carcinoma were reviewed to determine the efficacy of this treatment modality. Total radiation dose was either 48 or 57 Gray (Gy), while dose per fraction was either 3.0 or 4.0 Gy. Median disease free interval and survival were 365 and 450 days, respectively. Median disease free interval was shorter in dogs older than nine years (210 days) as compared with dogs less than or equal to nine years old (470 days), (p < .005). Median survival was shorter in dogs older than nine years (315 days) as compared with dogs less than or equal to nine years old (1080 days), (p < 0.02). Weight, stage, anatomic subsite, intraoral location, duration of disease, prior surgery, and number of radiation fractions did not appear to influence disease free interval or survival. Data presented herein suggest that survival in dogs with non-tonsillar squamous cell carcinoma receiving megavoltage radiation may be longer than that achieved with orthovoltage radiation or surgery. Megavoltage radiation appears to be an effective treatment for non-tonsillar oral squamous cell carcinoma in dogs. Further study is needed to determine the optimal time-dose sched-ule.  相似文献   
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A commercially available microbicide, composed of 5-Chloro-2-methyl-4-isothiPzolin-3-one and 2-methyl-4-isothiazolin-3-one, was tested for its in vivo effectiveness in controlling pathogenicity and mortalities in the marine shrimp Penaeus stylirostris , caused by the fungus Fusurium solani . Sub-adult shrimp (100% with Fusurium lesions) were treated with the microbicide at levels of 5.0 and 7.5 ppm (Trial 1) and with 1.0, 2.5 and 5.0 ppm (Trial 2), and each compared to a non-treated control. In Trial 1, treatments were administered during the first 9 days of the 22 day experiment, approximately every other day as 8 h static baths. The mean levels of Fusarium lesions on Day 22 for the 0, 5.0 and 7.5 ppm treatments were 87%, 25% and 13%, respectively. Statistically both levels of treatment (5.0 and 7.5 ppm) had significantly lower levels of Fusurium lesions when compared to the controls. In Trial 2, treatments of the microbicide were administered (8 h static bath) every seventh day over the course of the 64 day experiment. The Day 64 mean Fusarium lesion levels for the 0, 1.0, 2.5 and 5.0 ppm treatments were 54%, 59%, 10% and 7%, respectively. Treatment with 2.5 and 5.0 ppm reduced the prevalence of Fusarium lesions to statistically lower levels when compared to the 0 and 1.0 ppm treatments. The microbicide had earlier been reported to be highly toxic to fish. The use of activated charcoal filters on the microbicide-treated effluent appeared to remove any residual compound from the water. The data in the present study indicate a possible inverse relationship between the level of "BG 101" and growth rate. The data from both trials suggest that periodic treatment over a longer test period could limit or eliminate Fusurium lesions, which are known to be the potential cause of substantial mortalities, particularly in captive broodstock populations.  相似文献   
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