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排序方式: 共有559条查询结果,搜索用时 562 毫秒
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Donald E. Thrall DVM PHD Margaret C. McEntee DVM† Carol Novotney DVM† Marlene L. Hauck DVM† Rodney L. Page DVM MS† 《Veterinary radiology & ultrasound》1993,34(4):295-300
Eighteen dogs with malignant nasal cavity tumors were treated with radiation therapy, including a boost technique. Three 3:0 Gy boost doses were added to a treatment protocol consisting of sixteen 3.0 Gy daily fractions, bringing the total dose to 57 Gy. This boost technique was implemented without an associated increase in overall treatment time by giving the boost doses on a twice-a-day basis. Boost doses were given during the first half of the radiation therapy period. The treatment was completed as planned in 16 of the 18 dogs; two dogs received lower doses (51 and 54 Gy). Median survival was 177 days, poorer than in some other reported studies of nasal tumor irradiation. Acute effects were unacceptable, with 11 of the 18 dogs developing severe mucositis, desquamation, edema, swelling, and pruritus. The extensive nature of the acute reactions compromised assessment of the effect of the increased radiation dose on the tumor. Although there is justification for assessing more aggressive radiation protocols in canine nasal tumor patients, total doses approximating 60 Gy can not be given as described because of the inability of acutely responding normal tissues to compensate. 相似文献
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4.
Sean G. Sanders DVM Russell L. Tucker DVM Rodney S. Bagley DVM Patrick R. Gavin DVM PhD 《Veterinary radiology & ultrasound》2001,42(4):291-296
Magnetic resonance imaging (MR) was used to make a diagnosis of equine nigropallidal encephalomalacia in a horse. Equine nigropallidal encephalomalacia is a neurodegenerative disease that has many characteristics with Parkinson-like diseases in humans. Historically, horses were euthanized based on clinical signs and exposure to the toxic weed, yellow star thistle (Centaurea solstitialis). Previously, the disease has only been confirmed on necropsy. MR imaging can provide accurate and sensitive visualization of typical lesions seen in the brain of horses affected with equine nigropallidal encephalomalacia. Lesions were seen on T1-weighted, T2-weighted and proton density images. There was no contrast enhancement following Gd-DTPA administration. Lesions seen on MR were confirmed at necropsy. Using MR to confirm a diagnosis of equine nigropallidal encephalomalacia will prevent unnecessary suffering of horses and expense to owners that would otherwise incur, while further diagnostics are performed. 相似文献
5.
Pharmacokinetic and Phase I Evaluation of Carboplatin in Dogs 总被引:1,自引:1,他引:0
Rodney L. Page DVM MS Margaret C. McEntee DVM Steven L. George PhD Patrick L. Williams PhD Greta L. Heidner DVM Carol A. Novotney DVM Jim E. Riviere DVM PhD Mark W. Dewhirst DVM PhD Donald E. Thrall DVM PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1993,7(4):235-240
Thirty dogs with spontaneously occurring malignant neoplasms were treated monthly with carboplatin (CBDCA) given as a 30-minute intravenous infusion in a dose escalation study. Twenty-eight dogs were considered evaluable for toxicity. The maximally tolerated dose of CBDCA was conceptually defined as that dose, determined by logistic regression analyses of toxicity data, resulting in a 50% incidence of moderate toxicity (MOD50) or a 5% incidence of severe toxicity (SEV5). Each designated maximally tolerated dose was calculated for the first course of treatment only and for the first and second courses of treatment combined to estimate cumulative drug toxicity. The MOD50 and SEV5 for the first treatment course were 340 and 278 mg/M2, respectively. MOD50 and SEV5 values for the first plus second treatment courses were 327 and 231 mg/M2, respectively. The nadir of neutrophil and platelet counts occurred approximately 14 days after treatment. The mean neutrophil and platelet values for all dogs experiencing myelosuppression during the first two treatment courses were 1541/μL and 62,600/μL, respectively. Nonparametric pharmacokinetic analysis of plasma CBDCA values suggested that half-life (T1/2), area-under-the-curve and total body clearance (CLb) were not dose dependent. Volume of distribution (VDss) significantly increased with dose only between 100 and 150 mg/M2, not between 150 and 300 mg/M2. Dose-independent serum CBDCA pharmacokinetic disposition indicates that detailed investigation of tissue CBDCA distribution would be warranted and may identify novel dosing strategies that could improve the therapeutic index of CBDCA by minimizing toxicity. (Journal of Veterinary Internal Medicine 1993; 7:235–240. Copyright © 1993 by the American College of Veterinary Internal Medicine.) 相似文献
6.
Melody L. Danley P. Brett Kenney Patricia M. Mazik Rodney Kiser Joseph A. Hankins 《Journal of the World Aquaculture Society》2005,36(3):249-261
Rainbow trout Oncorhynchus mykiss (261.6 × 24.7 g initial weight, mean × SEM) at 13.1 × 0.2 C were exposed for 94 d to one of three CO2 treatments: control (22.1 × 2.8 mg/L), medium (34.5 × 3.8 mg/L), or high (48.7 × 4.4 mg/L). Trout were checked daily for survival, and fish were sampled at 0, 28, 56, and 84 d for physiological responses, growth, and fillet quality assessments. Trout were also challenged to a 15-min crowding stress at 93 d to assess their ability to initiate a stress response during hypercapnia. Chronically exposed trout showed nearly 100% survival through 84 d exposure (1 of 1,500 fish died). Growth and physiological results showed that increasing elevated CO2 , concentrations result in corresponding decreased growth rates and CO2 specific physiological parameters: The medium and high CO2 treatments had significantly slower growth and subsequently smaller fish by 84 d. Exposed trout also showed significantly ( P < 0.05) decreased plasma chloride for medium and high CO2 treatments compared to the control from 28 through 84 d. Decreased growth and smaller fish in the medium and high CO2 treatments resulted in correspondingly smaller fresh and smoked fillet weights. Chronic CO2 exposure did not result in notable changes in ultimate muscle pH. Exposure to 15-min crowding stress at 93 d resulted in significant changes in hematocrit, plasma cortisoI, glucose, and chloride for all treatment groups. CO2 -specific changes were detected in hematocrit, plasma cortisoI, and plasma chloride responses following the 15-min crowding stress. 相似文献
7.
Field studies with convalescent serum and infectious bursal disease vaccine to control turkey coryza
Convalescent serum given to 1-day-old poults delayed clinical signs of turkey coryza by several days and reduced mortality on infected farms. Turkey breeders immunized with cell-culture-adapted infectious bursal disease virus (IBDV) or turkey infectious bursal disease virus (TIBDV) had a marked increase in virus-neutralization (VN) antibody titers. The VN antibody titer was significantly higher in progeny poults than in poults from unimmunized breeders. Clinical turkey coryza and mortality was considerably less in poults from IBD- or TIBD-vaccinated breeders than in control poults. They also responded more favorably to hemorrhagic enteritis and fowl cholera vaccination. 相似文献
8.
Effects of land ownership and landscape-level factors on rare-species richness in natural areas of southern Ontario,Canada 总被引:5,自引:0,他引:5
Lovett-Doust J. Biernacki M. Page R. Chan M. Natgunarajah R. Timis G. 《Landscape Ecology》2003,18(6):621-633
Surprisingly few studies have considered the extent to which the nature of the ownership of land is associated with differences
in biodiversity. We analysed ownership and other landscape-level effects on rare-species richness for both globally- and regionally-rare
biota (including birds, herpetofauna, butterflies, mammals, and plants) in 289 designated natural areas (NAs) in southern
Ontario, Canada. Information about each NA −including area, number of plant communities, ownership status and details of species
diversity were collected from published sources. Length of perimeter of NA, relative isolation, and an estimate of fragmentation
were measured using image analysis and GIS techniques. NAs were in general relatively small, with mean area of 158 ha (median
85 ha, range from 0.9 to 1278 ha) for private NAs; public NAs had mean area of 132 ha (median 16 ha, range from 0.1 to 1481
ha). Mean number of plant communities was 4.6 (median 4, range 1- 13) at private NAs and 3.8 (median 3, range 1-16) at public
NAs. Our results show that, of several landscape-level factors, area had the greatest effects on rare-species richness and
other biotic indices. Effects of area were followed by effects of plant community diversity, however this was itself significantly
affected by area and the extent of perimeter of the NA. Both these factors were followed by effects of ownership of the NA
and by effects of isolation of the NA (represented by minimum distance to nearest NA and by number of NAs in 10 km radius).
Other landscape- level factors did not appear to have overall significant effects. Variation in area accounted for 0.1% to
29% of variation in number of rare species, with lower values for globally-rare, than for regionally-rare taxa. For all biotic
groups, public ownership of NAs was associated with significantly greater rare-species richness compared to private ownership,
even after other factors such as area were controlled. For all globally-rare biota except butterflies, area of NA had greater
effects on rare-species richness than did ownership. Richness of regionally- rare birds was more affected by plant community
diversity than by area of NA. Number of recorded plant communities accounted from 2.1% of variation in number of globally-rare
plant species to as high as 31% of variation in regionally-rare butterflies. The diversity of plant communities was itself
influenced by total site area (accounting for 45% of variation), extent of elongation of the NA, and both external- and interior-
edge perimeters. Public NAs had greatest numbers of rare biota and so should be a significant focus for conservation programs.
Smaller, privately-owned patches of natural area dominate (by number and area) in this densely populated region and their
significance should not be overlooked.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
Caecal intussusceptions and typhlocolitis in horses with severe Gastrodiscus aegyptiacus infestation 下载免费PDF全文
Z. Gratwick C. Donnellan P. C. Page A. Viljoen J. Williams C. H. Lyle 《Equine Veterinary Education》2018,30(5):247-254
The intestinal trematode Gastrodiscus aegyptiacus (G. aegyptiacus) has been recognised in equids around the world for many years, but its pathogenicity is yet to be confirmed. This report describes seven cases of severe G. aegyptiacus infestation, including six cases of caecal intussusception. 相似文献
10.