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51.
Expression of receptor tyrosine kinases VEGFR-1 (FLT-1), VEGFR-2 (KDR), EGFR-1, PDGFRa and c-Met in canine primary brain tumours 总被引:1,自引:0,他引:1
P. J. Dickinson B. N. Roberts R. J. Higgins C. M. Leutenegger A. W. Bollen P. H. Kass R. A. LeCouteur 《Veterinary and comparative oncology》2006,4(3):132-140
Inhibition of tumour growth and angiogenesis by targeting key growth factor receptors is a promising therapeutic strategy for central nervous system tumours. Characterization of these growth factor receptors in canine primary brain tumours has not been done. Using quantitative real‐time TaqMan polymerase chain reaction (PCR), we evaluated the expression of messenger RNA (mRNA) for five tyrosine kinase growth factor receptors (vascular endothelial growth factor receptor [VEGFR]‐1, VEGFR‐2, endothelial growth factor receptor [EGFR]‐1, platelet‐derived growth factor receptor a [PDGFRa], and c‐Met) relative to normal cerebral cortex in 66 spontaneous canine primary brain tumours. Increased expression of VEGFR‐1 and VEGFR‐2 mRNA was greatest in grade IV astrocytomas (glioblastoma multiforme) and grade III (anaplastic) oligodendrogliomas. EGFR‐1 mRNA expression was more consistently increased than the other receptors in all tumour types, while increased PDGFRa mRNA expression was mostly restricted to oligodendrogliomas. The similarities in increased expression of these tyrosine kinase growth factor receptors in these canine tumours, as compared to data from their human counterparts, suggest that common molecular mechanisms may be present. 相似文献
52.
20世纪90年代以来,广西桂林、柳州、贺州等地一些桔园的温州蜜柑和沙田柚出现了一种春梢叶片扭曲畸形、植株矮化的病害——温州蜜柑矮化病和柚矮化病,近年更有逐年加重的趋势。现已有实验证明,该两病均由茎陷点型衰退病毒引起。而近年广西一些桔园出现的纽荷尔脐橙果实变圆、变扁,个头变小,有时果顶部出现放射状沟,枝条木质部产生严重茎陷点的症状,也是由茎陷点型衰退病毒引起。《柑桔衰退病》一文简明扼要地介绍了柑桔衰退病的“症状、寄主范围、病原、流行病学、诊断检测及防控策略”,对于读者认识和治理温州蜜柑矮化病和柚矮化病可能会有所帮助。因此翻译出来,以供参考。 相似文献
53.
T. V. Balmer D. Irvine R. S. Jones † M. J. Roberts † L. Sungsby ‡ P. M. Taylor A. E. Waterman ‡ C. Waters § 《The Journal of small animal practice》1998,39(4):158-164
The postoperative analgesia and sedation in cats given carprofen (4·0 mg/kg bodyweight by subcutaneous injection preoperatively) was compared to that in cats given pethidine (3·3 mg/kg bodyweight by intramuscular injection postoperatively) in a controlled, randomised, blinded, multicentre clinical trial. Further dosing with the particular analgesic was allowed if a cat was exhibiting unacceptable pain. In total, 57 carprofen cases and 59 pethidine cases were evaluated. Significantly fewer cats in the carprofen group required additional doses of analgesic, and mean pain scores were significantly lower from four hours after ovariohysterectomy, and at 18 to 24 hours after castration, compared to the pethidine group. In conclusion, carprofen provided as good a level of postoperative analgesia as pethidine, but of a longer duration (at least 24 hours) and was well tolerated. It thus provides an option for 'pre-emptive analgesia' in cats about to undergo surgery. 相似文献
54.
THE DURAL TAIL SIGN IN THE DIAGNOSIS OF MENINGIOMAS 总被引:3,自引:0,他引:3
John P. Graham MVB MSc Susan M. Newell DVM MS Andra K. Voges DVM Gregory D. Roberts DVM MS Jay M. Harrison MS 《Veterinary radiology & ultrasound》1998,39(4):297-302
In humans the dural tail is a sign seen on contrast enhanced T1 weighted magnetic resonance images. This finding is considered specific for meningioma. The purpose of this study was to determine how often the dural tail occurs in cats and dogs and whether it is a specific sign for meningiomas in these species. MR examinations for eighteen dogs and four cats with proven diagnoses were reviewed. Diagnoses included ten meningiomas (seven dogs and three cats), three gliomas, two pituitary tumors, single examples of two other tumor types and five patients with mass lesions due to inflammatory disease. Contrast enhanced T1 weighted images were evaluated independently by three of the authors for the presence of a dural tail, without knowledge of the diagnoses. The results were compared to the diagnosis for each patient and the performance of individual reviewers compared. When their results were averaged, the reviewers reported the presence of a dural tail in 6 of 10 (60%) meningiomas, although detection varied between observers from 40% to 80%. Each reviewer had one false positive result, two reported a dural tail with a chromophobe adenocarcinoma and one with a toxoplasma meningoencephalitis. When a dural tail is seen an associated mass is most likely a meningioma. It is uncertain whether the dural tail represents neoplastic infiltration beyond the margins of the meningioma. This should be considered when planning treatment. 相似文献
55.
Roberts HF 《Science (New York, N.Y.)》1902,15(376):430-433
56.
Two experiments were conducted to evaluate two carrier proteins and nine adjuvants in promoting antibody production in heifers immunized against LH. The anti-LH antibody response was evaluated in heifers immunized against LH conjugated to either ovalbumin or keyhole limpet hemocyanin (KLH) (Exp. 1). In Exp. 2, an LH-ovalbumin conjugate was used to evaluate effectiveness of nine different adjuvants in antibody production. Weekly blood samples were collected from all heifers throughout the 23-wk study to determine LH antibody binding activity. In Exp. 1, heifers immunized with the LH-ovalbumin (LH-oval) conjugate had greater LH antibody binding activities (P less than .001) than those immunized with the LH-KLH conjugate. In Exp. 2, nine groups of heifers were immunized with LH-oval suspended in one of nine adjuvants; a 10th group was immunized against ovalbumin alone (control). Only adjuvants that contained at least 40% oil resulted in LH antibody binding activity that differed (P less than .01) from control. These results show that ovalbumin was a superior carrier protein to KLH in enhancing antibody production; adjuvants with greater than 50% oil were superior to those with less oil in promoting LH antibody production. 相似文献
57.
58.
BCG treatment of periocular sarcoid 总被引:2,自引:0,他引:2
J D Lavach K E Sullins S M Roberts G A Severin C Wheeler D C Lueker 《Equine veterinary journal》1985,17(6):445-448
Twenty-six horses and five mules with periocular sarcoids were treated with intralesional injections of a purified bacillus of Calmette and Guerin (BCG) cell walls in oil suspension. All sarcoids were cured and the horses and mules remained free from recurrence of sarcoid during the two-year follow-up period. 相似文献
59.
Six calves sensitised by implanting skin from a calf were later inoculated with lymphocytes from the same calf after the calf had been infected with bovine leukosis virus (BLV). Two out of 6 calves challenged did not develop BLV antibodies and BLV was not isolated from these animals, whereas all of the 5 control calves became infected with BLV. 相似文献
60.