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111.
112.
David R. Proulx DVM David M. Ruslander DVM Richard K. Dodge MS Marlene L. Hauck DVM PHD Laurel E. Williams DVM Birgitte Horn BVSc G. Sylvester Price DVM PHD Donald E. Thrall DVM PHD 《Veterinary radiology & ultrasound》2003,44(3):352-359
Despite the early notion that canine oral malignant melanoma is radioresistant, recent data suggest that external beam radiotherapy is effective in local tumor control. However, optimal fractionation schedules have not been established. The high rate of regional and distant metastasis is another problem that has hindered long-term control. The role of chemotherapy in the management of canine oral melanoma has also not been determined. In this study, data from 140 dogs irradiated at North Carolina State University were evaluated with the following objectives: (1) to compare the efficacy of three radiation therapy protocols (36 Gy, 9 Gy x 4 fractions; 30 Gy, 10 Gy x 3 fractions; or >45 Gy, 2-4 Gy x 12-19 fractions) for the treatment of dogs with oral malignant melanoma, (2) to identify any host or tumor factors influencing prognosis, and (3) to determine the impact of systemic chemotherapy on treatment outcome. Information regarding response to therapy, disease progression, and survival were determined from the medical records or from information obtained by telephone or mail survey. Relationships between host, tumor, and treatment variables and outcome measures (response, time to first event, and survival) were evaluated using Fisher's exact test (response) and the Cox regression model (time to first event and survival). The median time to first event for the 140 dogs was 5.0 months (95% C.I., 4-6 months) and the median survival was 7.0 months (95% C.I., 6-9 months). In the univariate analysis, the following variables were associated with increased time to first event and survival: (1) rostral tumor sublocation; (2) lack of bone lysis observed on skull imaging, and (3) microscopic tumor burden. In a multivariate analysis of 111 dogs with complete data for these variables, tumor sublocation, bone lysis, and tumor volume were identified as joint predictors of time to first event (p < .001, p < .001, and p = .04, respectively) and survival (p < .001, p < .001, and p = .05, respectively). There were no differences in response, time to first event and survival between the three radiation therapy protocols used. Systemic chemotherapy had no impact on the development of metastatic disease, time to first event, or survival, although the dosages used in this study were suboptimal. External beam radiation therapy is effective in local disease control of canine oral malignant melanoma; however, the optimal fractionation scheme has yet to be determined. The high metastatic rate observed with this disease and the inefficacy of systemic chemotherapy indicate that further investigation into novel therapies is warranted. 相似文献
113.
Two horses, presented for investigation of chronic weight loss despite normal to increased feed intake, had flat oral glucose absorption curves, suggesting malabsorption. The cause of the apparent malabsorption was not evident grossly or on light microscopic examination of the intestinal tract. Both horses survived long term and at follow-up examination had regained weight and their capacity to absorb glucose. These cases illustrate that flat glucose absorption curves may occur in horses with no obvious intestinal lesions, that they may revert to normal and that the results of these tests should be interpreted with caution. 相似文献
114.
复合免疫增强剂对断奶仔猪猪瘟免疫的影响 总被引:2,自引:0,他引:2
通过对断奶仔猪投服复合免疫增强剂 ,研究其对猪瘟的免疫状况、血象和生化指标的影响。结果 :试验组猪瘟抗体效价明显升高 ,与对照组相比 ,差异显著 (P <0 0 5 ) ;血小板 (PLT)、丙氨酸氨基转移酶 (ALT)、血清总蛋白 (TP)、尿素氮 (BUN)等呈上升趋势 ,白细胞总数 (WBC)、红细胞总数 (RBC)、血红蛋白 (HGB)、天东氨酸氨基转移酶 (AST)、血糖 (GLU)等呈上升趋势 ,但血象、生化指标组间无明显差异 (P >0 0 5 )。表明 ,此复合免疫增强剂能显著增强猪瘟疫苗免疫效果 ,对血象和生化指标无明显影响 相似文献
115.
砂土地肥料配施对小麦产量和土壤肥力的影响 总被引:1,自引:0,他引:1
彩四因子干净人通用旋转设计,研究了砂土地施用有机肥、氮、肥、磷肥和钾肥对小麦产量的作用和对土壤肥力的影响及其施肥因子之间的交互作用和最适配比。结果表明:有机肥、氮肥、磷肥和钾肥与小麦产量呈二次回归关系,砂土地要提高产量和培肥地力应立足于肥料配合施用,重施有机肥,酌情多施磷肥。 相似文献
116.
以麦胚为主要原料,通过磨浆的方法,采用梯度试验和正交试验,确定了麦胚口服液的最佳工艺条件为:料水比1∶6,加酶量0.2%,95℃保持40min;活性炭加入量为0.5%;适宜浓缩比2.7∶1。对所得产品进行了抗氧化试验,添加0.01%的尼泊金乙酯,能有效地抑制麦胚液中不饱和脂肪酸的氧化。 相似文献
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118.
The role of disturbance in structuring vegetation is widely recognized; however, we are only beginning to understand the effects of multiple interacting disturbances on ecosystem recovery and development. Of particular interest is the impact of post-disturbance management interventions, particularly in light of the global controversy surrounding the effects of salvage logging on forest ecosystem recovery. Studies of salvage logging impacts have focused on the effects of post-disturbance salvage logging within the context of a single natural disturbance event. There have been no formal evaluations of how these effects may differ when followed in short sequence by a second, high severity natural disturbance. To evaluate the impact of this management practice within the context of multiple disturbances, we examined the structural and woody plant community responses of sub-boreal Pinus banksiana systems to a rapid sequence of disturbances. Specifically, we compared responses to Blowdown (B), Fire (F), Blowdown-Fire, and Blowdown-Salvage-Fire (BSF) and compared these to undisturbed control (C) stands. Comparisons between BF and BSF indicated that the primary effect of salvage logging was a decrease in the abundance of structural legacies, such as downed woody debris and snags. Both of these compound disturbance sequences (BF and BSF), resulted in similar woody plant communities, largely dominated by Populus tremuloides; however, there was greater homogeneity in community composition in salvage logged areas. Areas experiencing solely fire (F stands) were dominated by P. banksiana regeneration, and blowdown areas (B stands) were largely characterized by regeneration from shade tolerant conifer species. Our results suggest that salvage logging impacts on woody plant communities are diminished when followed by a second high severity disturbance; however, impacts on structural legacies persist. Provisions for the retention of snags, downed logs, and surviving trees as part of salvage logging operations will minimize these structural impacts and may allow for greater ecosystem recovery following these disturbance combinations. 相似文献
119.
CS3是CFA(产肠毒素型大肠杆菌引起腹泻时产生两类毒性因子之一)阳性株的保护性抗原。临床研究结果表明,以CS3作为疫苗可有效地防止由相关细菌导致的腹泻(董自正等, 相似文献
120.
复方茵芩制剂中黄芩苷的药代动力学研究 总被引:1,自引:1,他引:1
探讨复方茵芩制剂有效成分黄芩苷在小鼠体内的药物代谢动力学特征,按16.5 g.kg-1(相当于黄芩苷239.5 mg.kg-1)的剂量给小鼠口服复方茵芩制剂,用高效液相色谱法(HPLC)检测用药后0.25、0.5、1.0、2.0、3.0、4.0、5.0、6.0、8.0、12.0、14.0、16.0、20.0、24.0、36.0、48.0、72.0 h血浆中药物黄芩苷的质量浓度,研究在小鼠体内的药物代谢动力学.结果表明,复方茵芩制剂中黄芩苷在小鼠体内的药时数据符合开放性二室模型,动力学方程为:C=16.76 e-0.45t+3.10 e-0.03t-20.99 e-2.13t;主要药代动力学参数:T1/2α1.54 h,T1/2β5.25±2.96 h,T1/2 Ka0.34 h,AUC0→∞128.99 mg.L-1.h-1,CL/F0.19 L.h-1,Vd/F6.363 L.kg-1,Tpeak1.05 h,Cmax11.19μg.mL-1. 相似文献