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91.
Introduction:  The clinical impression of many oncologists is that Rottweilers with appendicular osteosarcoma (OSA) have an unfavorable prognosis despite standard therapy (amputation and chemotherapy). The purpose of this study was to compare clinical characteristics, biological behavior and outcome of OSA in Rottweilers to that of other breeds.
Methods:  107 OSA cases were studied: 56 clinical cases (17 Rottweilers) and 54 necropsy submissions (13 Rottweilers) of OSA (3 cases overlapping). Information regarding signalment, prognostic factors, treatment and outcome was obtained from medical records and follow‐up with owners. Data were analyzed by chi‐square test, t‐test, and log rank test.
Preliminary Results:  Compared to other breeds Rottweilers were more likely to have femur (23% vs. 16%) and ulna (15% vs. 3%) and less likely to have tibia (8% vs. 27%) as their primary tumor location (p = 0.04). In the necropsy group, Rottweilers had a younger age at death (6.4 vs. 10 years, p = 0.0002) and a greater body weight at diagnosis (49 vs. 37 kg, p = 0.002). No statistical differences in the age at diagnosis or survival time were noted in Rottweilers vs. other breeds. Metastasis to lymph nodes (31% vs. 10%, p = 0.08) and lungs (64% vs. 49%, p = 0.24) was more frequent in Rottweilers. There was no difference in chemotherapy drugs given; however, Rottweilers were 20 times more likely to receive NSAIDs (p = 0.0004).
Conclusion:  Greater body weight with a predilection for certain tumor locations may contribute to OSA development in Rottweilers. A younger age at death may suggest a more aggressive phenotype.  相似文献   
92.
Introduction:  Canine hemangiosarcoma (HSA) is a fatal malignancy and most dogs die within 6–8 months of diagnosis. The spleen is a common primary site, representing 50% of all cases. These dogs typically present with clinical signs due to tumor rupture and intra‐abdominal dissemination; the abdomen is also the main site of disease progression when these patients fail. Direct delivery of chemotherapy into the abdominal cavity may therefore be a rational approach in this malignancy.
Methods:  14 dogs with stage 2 or 3 splenic HSA were recruited. Doxil at a dose of 1 mg/kg was diluted in saline and administered via ultrasound‐guidance into the abdominal cavity. The dogs were scheduled to receive 4 treatments every 3 weeks. Samples of plasma and abdominal fluid were collected for pharmacokinetic analysis. All dogs were monitored for recurrence and complete necropsies were requested at death.
Results:  8 dogs with stage 3 and 6 dogs with stage 2 HSA were enrolled. All 14 dogs have died, 12/14 due to tumor and 2 from other causes. There was no difference in median survival days between stages (stage 2: 244, stage 3: 125, p = .22). All 12 dogs that died due to tumor‐related causes failed with intra‐abdominal recurrence. Necropsies showed that the dogs in this study had relatively fewer extra‐abdominal metastasis compared to dogs treated with systemic chemotherapy. Pk analysis showed detectable plasma doxorubicin 1 and 2 weeks after treatment.
Conclusion:  Direct abdominal administration of Doxil did not prevent intra‐abdominal recurrence; however, it appeared to provide effective systemic coverage.  相似文献   
93.
Introduction:  Splenic lesions are a common finding in veterinary medicine and typically 1/2 to 2/3 of these lesions are malignant. Due to the limited accuracy of ultrasound, unnecessary exploratory surgeries/biopsies may be performed for benign lesions and treatment may be delayed for malignant ones. Splenic lesions are rare in people. MR imaging, with its inherently high soft tissue contrast, is efficacious in imaging the human spleen. We have previously demonstrated the efficacy of MRI to differentiate canine hepatic lesions. In that study 8 splenic lesions were all accurately characterized. This current study represents a further evaluation of splenic lesions.
Methods:  In this prospective study, 27 dogs with splenic lesions were accrued. Histopathological/cytological confirmation of lesions occurred either before or shortly after imaging. MRI clinicians were blinded to histopathology results. MR (General Electric, 1.5 Tesla) images using a variety of sequences were obtained before and after intravenous administration of gadolinium.
Results:  32 lesions (9 malignant, 23 benign) were evaluated in 27 dogs. Lesions were confirmed via histopathology (n = 20) or cytology (n = 12). Benign lesions included, EMH (n = 7), hematoma/hemorrhage (n = 5), lymphoid hyperplasia (n = 9), and hemangioma (n = 2). Malignant lesions included anaplastic sarcoma (n = 3), malignant histiocytosis (n = 2), hemangiosarcoma (n = 2), plasma cell tumor (n = 1) and adenocarcinoma (n = 1). The overall accuracy in differentiating benign from malignant lesions was 88%(29/32 lesions). The overall sensitivity and specificity were 100%(95% CI, 66–100) and 87%(95% CI 66–97).
Conclusions:  Based upon these results, MRI is both sensitive and specific in distinguishing between malignant and benign splenic lesions.  相似文献   
94.
Measurement of plasma cardiac troponin I concentration ([cTnI]) is a sensitive and specific means for detecting myocardial damage in many mammalian species. Studies have shown that [cTnI] increases rapidly after cardiomyocyte injury. The molecular structure of cTnl is highly conserved across species, and current assays developed for its detection in humans have been validated in many species. In this study, [cTnI] was quantified using a 2-site sandwich assay in plasma of healthy control cats (n = 33) and cats with moderate to severe hypertrophic cardiomyopathy (HCM) (n = 20). [cTnI] was significantly higher in cats with HCM (median, 0.66 ng/mL; range, 0.05-10.93 ng/mL) as compared with normal cats (median, <0.03 ng/mL; range, <0.03-0.16 ng/mL) (P < .0001). An increase in [cTnI] was also highly sensitive (sensitivity = 85%) and specific (specificity = 97%) for differentiating cats with moderate to severe HCM from normal cats. [cTnI] was weakly correlated with diastolic thickness of the left ventricular free wall (r2 = .354; P = .009) but not with the diastolic thickness of the interventricular septum (P = .8467) or the left atrium: aorta ratio (P = .0652). Furthermore, cats with congestive heart failure at the time of cTnI analysis had a significantly higher [cTnI] than did cats that had never had heart failure and those whose heart failure was controlled at the time of analysis (P = .0095 and P = .0201, respectively). These data indicate that cats with HCM have ongoing myocardial damage. Although the origin of this damage is unknown, it most likely explains the replacement fibrosis that is consistently identified in cats with moderate to severe HCM.  相似文献   
95.
Vascular endothelial growth factor (VEGF) has potent angiogenic, mitogenic, and vascular permeability enhancing properties specific for endothelial cells. VEGF is present in high concentrations in inflammatory and neoplastic body cavity effusions and has been implicated in the pathogenesis of neoplastic and inflammatory effusion formation. In this study, VEGF was quantitated by solid-phase enzyme-linked immunoadsorbent assay (ELISA) in samples of pericardial, pleural, and peritoneal effusions (N = 38) from dogs (N = 35) with neoplastic and non-neoplastic diseases. VEGF was detected in 37 of 38 effusions (median, 754; range, 18-3,669 pg/mL) and was present in much higher concentrations than in previously established normal concentrations for canine plasma (median, < 1 pg/mL; range, < 1-18 pg/mL) or in those previously noted in the plasma of dogs with hemangiosarcoma (HSA; median, 17 pg/mL; range, < 1-67 pg/mL). In 4 dogs with HSA, the concurrent plasma VEGF concentration was much lower than in the abdominal effusion (P = .029). No significant correlation was demonstrated between VEGF effusion concentration and effusion total protein content or nucleated cell count. Mean VEGF concentrations were significantly higher in pericardial (median, 3,533; range, 709-3,669 pg/mL) and pleural effusions (median, 3,144; range, 0-3,663 pg/mL) compared to peritoneal effusions (median, 288; range, 18-2,607 pg/mL; P < .05). There was no marked difference demonstrated between effusions associated with malignant and nonmalignant diseases. Further studies are necessary to elucidate the role of VEGF in body cavity effusion formation in dogs.  相似文献   
96.
A number of chlorinated 1,2-, 1,3- and 1,4-benzodicarbonitriles monosubstituted by either hydroxy, arylamino, alkylthio, sulphinyl or sulphonyl groups were synthesised and assayed against P. viticola, P. oryzae, V. inaequalis, P. parasitica and a number of other fungi and bacteria. The 1,3-benzodicarbonitriles were the most active compounds and the alkylsulphiyl and sulphonyl groups the most effective substituents.  相似文献   
97.
这5类中有很大一部分不能被人直接利用。事实上,草料和许多食品加工副产物并不能被人食用。此外,作为杂食动物的人既需要食用植物来源的食物也需要动物来源的食物以满足其最佳生长和发育。  相似文献   
98.
OBJECTIVE: To evaluate whether cutting equine subchondral bone to demarcate specific regions of interest (ROIs) influences the mean density for that bone as measured via quantitative computed tomography (QCT). Sample population-2 metacarpophalangeal joints from equine cadavers. PROCEDURES: The distal portion of the third metacarpal bone of each intact metacarpophalangeal joint was scanned via CT to simulate in vivo conditions. Each joint was subsequently disarticulated and dissected, and the distal portion of the dissected third metacarpal bone in air was scanned. Then, six 1-cm(2) areas representing ROIs were cut into the distal condylar surfaces to depths of approximately 1 cm, and the bone was scanned again. Three-dimensional CT models of the 3 bone preparations were generated for each third metacarpal bone on the basis of data from each set of scan images, and densities of the 6 ROIs were measured. Mean bone densities for the 6 ROIs were compared among models of intact, dissected, and cut third metacarpal bone scans. RESULTS: Mean bone density was significantly lower in cut bone preparations, compared with that in intact or dissected bone. Differences between mean bone densities for intact and dissected bone preparations were not significant. CONCLUSIONS AND CLINICAL RELEVANCE: Cutting subchondral bone to demarcate specific ROIs prior to CT imaging significantly lowered mean bone density as measured via QCT and thus introduced substantial artifacts. These findings have direct implications on techniques for CT modeling of equine subchondral bone in the characterization of joint diseases in horses.  相似文献   
99.
Research was conducted to determine the effects of boiling, refrigerating, and microwave heating on the cooked quality and stability of lipids in macaroni containing 15% (w/w) ground flaxseed. Boiling increased brightness but decreased redness and yellowness of macaroni containing ground flaxseed. Boiled macaroni and boiled‐refrigerated‐microwave heated (BRMH) macaroni had similar appearance. After boiling, cooking loss was lower and cooked firmness was greater for macaroni dried at ultra‐high temperature (90°C) than at low temperature (40°C). Macaroni fortified with ground flaxseed had lower cooking loss than did nonfortified macaroni. Firmness was greatest with boiled, intermediate with boiled‐refrigerated (BR), and least with BRMH macaroni. Cooking in boiling water reduced extractable lipid content of macaroni with flaxseed. Boiled‐refrigerated and BRMH macaroni with flaxseed had similar extractable lipid contents and were lower than that for boiled macaroni with flaxseed. Free fatty acid content was greatest with dried, intermediate with boiled, and least with BR and BRMH macaroni with flaxseed. Boiling, refrigerating, and microwave heating did not affect conjugated diene content in lipid extracted from macaroni with flaxseed, regardless of drying temperature.  相似文献   
100.
Five mixed-breed dogs underwent splenic sequestration scintigraphy following intravenous injection of 647.5 to 740 MBq (17.5–20 mCi) of 99mTechnetium labeled autologous red blood cells (RBCs) that had been chemically denatured using two μg of stannous chloride. Left lateral dynamic images were obtained for 20 minutes after injection. Regions of interest (ROI) were drawn around the splenic body and ventral extremity, ventral liver and caudal abdominal great vessels and time activity curves created. Count density information was obtained and uptake ratios were calculated for the spleen ROI/vessel ROI, liver ROI/vessel ROI and spleen ROI/liver ROI at 1, 2.5, 5, 10, 15 and 20 minutes after injection. Two additional studies using different RBC denaturing procedures were done in four of the five dogs. In the second study, the stannous chloride level was doubled to 4.0 μg, while in the third study, the RBCs were denatured by addition of 2.0 μg of stannous chloride and heating at 49°C for 15 minutes. Progressive splenic uptake of denatured RBCs was seen in all dogs during the first 15 to 20 minutes of each study, no matter which denaturing technique was utilized. Significant increases in the spleen ROI:/vessel ROI and spleen ROI:liver ROI ratios were obtained at 5, 10, 15 and 20 minutes when compared to the 1 minute values for each of the labeling techniques. A significant difference was not identified between the three ratios at 15 minutes between the three labeling techniques. There was a trend of increasing values for each ratio where 2.0 μg of stannous chloride technique being the lowest, 4.0 μg of stannous chloride having an intermediate value and the heated technique had the highest values. The heating technique resulted in higher liver activity and increased variability of the mean liver ROI/vessel ROI ratios at all times (1, 2.5, 5,10, and 15 minutes). Using a non-linear least squares regression analysis, a double exponential equation fit the spleen ROI/vessel ROI and spleen ROI/liver ROI ratios for all three labeling techniques. Imaging of the spleen using all three techniques was acceptable, and a persistent blood pool image would allow for vascular imaging and cardiac gated studies 30 minutes after injection of the denatured, labeled autologous red blood cells. Veterinary Radiology & Ultrasound, Vol. 36, No. I, 1995, pp 57–63.  相似文献   
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