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This paper describes in detail a combined dorsal and intraoral approach for maxillectomy for tumors involving tissues more caudal to the third premolar. The only intraoperative complication was that of blood loss, with six out of 20 dogs requiring a single unit of blood. Histopathologically clean margins were obtained in 14 of the 20 cases, with a recurrence rate of 50% in these dogs and a median time to recurrence of 24 months. This represents an improvement in outcome over previously reported studies, and the authors postulate this is due to the better exposure and access to the area afforded by the combined approach over the standard intraoral approach.  相似文献   
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Avian polyomavirus (APV) is one of the most significant pathogens of domestically raised psittacine birds (parrots). One or more APVs are suspected to infect nonpsittacine cage birds, but the relationship of these viruses to the APV infecting parrots remains unclear. In this report, for the first time, we fully document an APV infection in a nonpsittacine cage bird, a green aracaris (Pteroglossus viridis). Grossly, this bird evidenced generalized hemorrhage. Histologically, there was severe hepatic necrosis, splenic necrosis, and the presence of lightly basophilic to clear pannuclear inclusion bodies and karyomegaly in splenocytes and renal mesangeal cells, all characteristic lesions of APV infection in parrots. APV DNA was amplified directly from the liver by polymerase chain reaction and sequenced. The virus differed from the original APV sequence by only 24 base pairs (0.48% of the genome), demonstrating that it is a variant of the APV. A serologic survey of the remaining birds in the aviary demonstrated anti-APV antibody in two cockatoos, two cockatiels, a laughing kookaburra, a Lady Ross turaco, and five zebra finches. The remaining green aracaris was seronegative. The sequence and serologic data suggest that the APV that infected the green aracaris originated in a parrot and was capable of infecting birds from at least four orders.  相似文献   
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Breeding for organic agriculture: the example of winter wheat in Austria   总被引:2,自引:2,他引:0  
Breeding for organic agriculture (BFOA) is a strategy for a commercial breeding company based on the exploitation of the frequently observed high correlation for many traits between conventional, low input (LI) and organic agriculture (ORG). Indirect selection under LI can be useful to roughly divide the germplasm into the genotypes better adapted to high input and those better adapted to LI or ORG conditions. BFOA is an evolving process, in which two methods are currently applied: early generations are either selected following the pedigree system under LI, or grown as bulk populations on ORG fields. In the latter case the system switches to LI after individual ear selection under ORG conditions. In both methods, the first replicated yield trial is grown parallel under ORG and LI. Subsequently, the genotypes are grouped into conventional or ORG advanced trial series. The BFOA strategy allows that the larger genetic variability of both the organic and conventional gene pool can be exploited in the selection for ORG. Hitherto, seven winter wheat varieties were released in Austria after exclusive organic VCU testing.  相似文献   
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OBJECTIVE: To compare surgical and oncologic outcome in dogs with osteosarcoma (OSA) of the distal aspect of the radius treated with limb-sparing surgery, using either a cortical allograft or endoprosthesis, and postoperative chemotherapy; and to evaluate predictive factors for outcome. STUDY DESIGN: Prospective cohort study. ANIMALS: Dogs (n = 20) with spontaneous, non-metastatic OSA of the distal aspect of the radius. METHODS: Dogs were prospectively randomized for limb-sparing surgery with either a cortical allograft (n = 10) or endoprosthesis (10) and full-course adjuvant chemotherapy using single or dual agent protocols of cisplatin, carboplatin, and/or doxorubicin. Surgical (intraoperative findings, postoperative infection, construct failure) and oncologic (local tumor recurrence, metastasis, survival) outcomes were compared. The influence of intraoperative and postoperative variables on surgical and oncologic outcome were evaluated. RESULTS: No clinically significant differences in surgical and oncologic outcome were detected between groups. The percentage of radius replaced by the implant was significantly greater in the endoprosthesis group (60.9% compared with 48.6%, P = .008). Median survival time (MST) for dogs with construct failure, regardless of implant type, was 685 days and significantly greater than MST of dogs without construct failure (322 days, P = .042; hazard ratio [HR] 16.82). Median metastasis-free interval and MST (685 days versus 289 days; P = .034, HR 24.58) were significantly greater in dogs with postoperative infection. Disease-free and overall limb-salvage rates were 70% and 85%, respectively. Overall MST was 430 days. CONCLUSIONS: For dogs with OSA of the distal aspect of the radius, a cortical allograft or endoprosthesis can be used for limb-sparing surgery. Construct failure and postoperative infection significantly improve survival time regardless of implant type. CLINICAL RELEVANCE: An endoprosthesis is an attractive alternative to cortical allografts for limb-salvage of the distal aspect of the radius in dogs because surgical and oncologic outcomes are similar, but the endoprosthesis is an immediately available off-the-shelf implant which is not complicated by the bone harvesting and banking requirements associated with cortical allografts. Mechanisms whereby postoperative infection improves survival time requires further investigation and, if elucidated, may provide the opportunity to improve the outcome of dogs and humans with OSA.  相似文献   
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The ESP II Culture System (ESP II), a broth-based culture system, has been modified and optimized for culturing Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) in animal feces since 2000. Conventional and real-time polymerase chain reaction (PCR) assays based on the IS900 sequence were performed as confirmatory tests for M. paratuberculosis in ESP II liquid culture medium. There were no differences between test results of conventional and real-time PCR assays. During the 5-week incubation period, if acid-fast bacilli (AFB) were detected in ESP culture-positive samples, IS900 PCR assays were performed to confirm whether those AFB were M. paratuberculosis. At the end of the 5-week incubation, AF staining was performed on all ESP II-negative cultures to screen any false-negative cultures; IS900 PCR assays were performed on AFB-positive cultures. During a period of 1 year, of a total of 18,499 ESP II cultures, 2,814 (15.2%) PCR confirmation assays were performed. Of those, 2,259 (80%) were both ESP and PCR positive; 104 (4%) were ESP positive and PCR negative; 423 (15%) were ESP negative and PCR positive; 28 (1%) were both ESP and PCR negative. The AF-staining step after the 5-week incubation produced 423 (15%) more PCR-positive cultures. Of a total of 2,814 AFB-positive cultures, 132 (5%) were not confirmed as M. paratuberculosis. Further studies are needed for speciation of non-M. paratuberculosis isolates.  相似文献   
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In an earlier study, chromosome 1D of the hexaploid breadwheat cultivar ‘Chinese Spring’ was introduced into hexaploid triticale to improve its bread‐making quality. That specific chromosome, 1D, carried the a allele at the Glu‐D1 locus coding for high molecular weight (HMW) glutenin subunits 2 + 12, and since subunits 2 + 12 are associated with poor bread‐making quality in wheat, in the present study hexaploid 1D substitution triticale was crossed with octoploid triticale with the d allele at the Glu‐D1 locus encoding HMW glutenin subunits 5 + 10. Following backcrosses to different triticale varieties, 1D substitution lines were established that had Glu‐D1 allele a or d in an otherwise genetically similar background, and the influence of these two different alleles on bread‐making quality of hexaploid triticale was compared. The agronomic performance of 76 selected lines was evaluated in a field trial. The Zeleny sedimentation value was determined as a parameter for bread‐making quality, and related to the presence of chromosome 1D, the different glutenin alleles and the nature of the substitution. The presence of chromosome 1D had a significant and positive effect on the Zeleny sedimentation value, but the difference between the two glutenin alleles 2 + 12 and 5 + 10 was not as obvious as in wheat. Owing to its high cytological stability and minimal effect on agronomic performance, substitution 1D(1A) appears to be the most desirable one to use in triticale breeding.  相似文献   
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Cadmium (Cd) is a toxic heavy metal that occurs naturally in soils. Durum wheat is known to accumulate generally more Cd than other cereal crops. The uptake of Cd in durum wheat is governed by the gene Cdu1, which co‐segregates with several DNA markers, such as the co‐dominant marker usw47 and the dominant marker ScOPC20. A panel of 314 durum wheat cultivars or lines originating from 16 countries or regions were assessed with usw47. The plant material was mainly comprised of cultivars and modern breeding lines. From this set, 165 durum wheat lines were classified as low‐Cd accumulators, 144 high‐Cd accumulators and five were heterogeneous. A smaller subset of 16 cultivars had previously been evaluated for Cd accumulation in replicated field trials. Lines with the high‐Cd allele showed a 2.4‐fold higher Cd content in the seeds than lines with the low‐Cd allele. We also compared the utility of markers usw47 and ScOPC20 as selection tools. Marker‐assisted selection appears as a robust and practicable tool for breeding durum cultivars with low‐Cd content.  相似文献   
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Background: Identification of biomarkers that predict outcomes in dogs with osteosarcoma (OSA) would be valuable to veterinarians and owners. Leukocyte numbers in peripheral blood are associated with outcomes in some types of cancer in humans. Hypothesis/Objectives: We hypothesized that increased numbers of monocytes would be associated with reduced disease‐free interval (DFI) in dogs with OSA. Animals: Medical data from 69 dogs with appendicular OSA treated with amputation and chemotherapy were selected for study. Methods: Retrospective study. Statistical associations were assessed by univariate and multivariate analysis. Information about DFI and leukogram values, tumor location, and serum alkaline phosphatase was abstracted from the medical record. Results: Higher numbers of circulating monocytes (>0.4 × 103 cells/μL) and lymphocytes (>1.0 × 103 cells/μL) before treatment were found to be significantly (P < .05) associated with shorter DFI in dogs with OSA. Other parameters associated with poor outcomes were increased alkaline phosphatase, primary tumor location, and age. Conclusion and Clinical Importance: These results indicated that pretreatment evaluation of monocyte and lymphocyte counts provided prognostic information for dogs with appendicular OSA. Notably, most animals in this study had monocyte counts within the normal reference range, indicating that variations within the reference range of leukocyte values might also have prognostic significance.  相似文献   
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