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31.
Gunduz I  Buss GR  Chen P  Tolin SA 《Phytopathology》2004,94(7):687-692
ABSTRACT Resistance to Soybean mosaic virus (SMV) was identified in PI 88788 soybean, a germ plasm accession from China that is used widely as a source of resistance to soybean cyst nematode. Strains SMV-G1 through -G7 infected the inoculated leaves of PI 88788 but were not detected in upper, noninoculated trifoliolate leaves. Inheritance of resistance was determined by inoculating progenies of crosses of PI 88788 with susceptible cvs. Essex and Lee 68 with SMV strains G1 and G7. Allelomorphic relationships with known genes for resistance to SMV were tested in crosses with the resistant genotypes PI 96983, L29, and V94-5152, possessing Rsv1, Rsv3, and Rsv4 genes, respectively. Data analyses showed that resistance in PI 88788 to SMV-G1 is controlled by a single, partially dominant gene; however, to SMV-G7, the same gene was completely dominant. The PI 88788 gene was independent of the Rsv1 and Rsv3 loci, but allelic to Rsv4 in V94-5152. Expression of the Rsv4 gene in PI 88788 resulted in a reduced number of infection sites and restricted short- and long-distance movement of virus, rather than hypersensitivity. A unique late susceptible phenotype was strongly associated with heterozygosity. This gene has potential value for use in gene pyramiding to achieve resistance to several SMV strains, as well as for rate-reducing resistance.  相似文献   
32.
The responses of 15 cats with histologically (n=14) or cytologically (n=1) confirmed nasal squamous cell carcinoma treated with (90)Strontium plesiotherapy were reviewed retrospectively. Cats were treated such that a total dose of 50Gy was delivered at a depth of 2mm, administered in five fractions over a 10-day period. Of the cats, 11 were stage T(2), three were T(is) and one had only a cytological diagnosis precluding staging. Eleven of the cats achieved complete response (no visible lesion after 6-8 weeks) following the first cycle of therapy, and two cats with partial response achieved complete response with a second cycle of therapy. The remaining two cats achieved partial response following therapy, but further intervention was declined. Euthanasia was performed in these two cats because of progressive disease after 81 and 142 days. Of the 85% of cats that achieved a complete response, there was no recurrence of disease during a follow-up period of 134-2,043 days (median 652 days). In addition to prolonged disease-free survivals, (90)Strontium therapy produced excellent cosmetic results from the owners' perspective. These results demonstrate that superficial squamous cell carcinoma of the feline nasal planum responds excellently to (90)Strontium plesiotherapy, and this form of therapy may offer advantages over other alternatives currently available.  相似文献   
33.
CASE DESCRIPTION: A 5-year-old sexually intact male cockatiel was examined because of progressive dyspnea of 1 week's duration. CLINICAL FINDINGS: On auscultation of the lungs and air sacs, crackles were detected; the abdomen was distended and fluctuant on palpation. Eleven milliliters of clear yellow fluid was collected via abdominocentesis. Radiography (with and without contrast medium) and ultrasonography revealed a soft tissue mass in the caudoventral portion of the coelom. TREATMENT AND OUTCOME: Exploratory surgery of the coelomic cavity was performed and the neoplasm was excised. Histologic examination of the neoplasm was consistent with a high-grade pancreatic exocrine adenocarcinoma. Celecoxib, a cyclooxygenase (COX)-2 inhibitor, was administered for pain management and for potential antineoplastic activity. For 4.5 months after surgery, the bird had no recurrence of clinical signs; however, dyspnea recurred and during evaluation, the bird died. Necropsy findings indicated that the pancreatic adenocarcinoma had metastasized to surrounding tissues and vessels, which was not unexpected given the high grade assigned to the neoplasm during histologic analysis. CLINICAL RELEVANCE: Pancreatic neoplasms are associated with a poor prognosis, regardless of treatment modality. Celecoxib can be administered as palliative treatment to affected birds, but as with any nonsteroidal anti-inflammatory drug, COX-2 inhibitors should be used cautiously because they can adversely affect renal function by decreasing renal prostaglandin synthesis.  相似文献   
34.
OBJECTIVE: To evaluate the pharmacokinetic-pharmacodynamic parameters of enrofloxacin and a low dose of amikacin administered via regional IV limb perfusion (RILP) in standing horses. ANIMALS: 14 adult horses. PROCEDURES: Standing horses (7 horses/group) received either enrofloxacin (1.5 mg/kg) or amikacin (250 mg) via RILP (involving tourniquet application) in 1 forelimb. Samples of interstitial fluid (collected via implanted capillary ultrafiltration devices) from the bone marrow (BMIF) of the third metacarpal bone and overlying subcutaneous tissues (STIF), blood, and synovial fluid of the radiocarpal joint were collected prior to (time 0) and at intervals after tourniquet release for determination of drug concentrations. For pharmacokinetic-pharmacodynamic analyses, minimum inhibitory concentrations (MICs) of 16 microg/mL (amikacin) and 0.5 microg/mL (enrofloxacin) were applied. RESULTS: After RILP with enrofloxacin, 3 horses developed vasculitis. The highest synovial fluid concentrations of enrofloxacin and amikacin were detected at time 0; median values (range) were 13.22 microg/mL (0.254 to 167.9 microg/mL) and 26.2 microg/mL (5.78 to 50.0 microg/mL), respectively. Enrofloxacin concentrations exceeded MIC for approximately 24 hours in STIF and synovial fluid and for 36 hours in BMIF. After perfusion of amikacin, concentrations greater than the MIC were not detected in any samples. Effective therapeutic concentrations of enrofloxacin were attained in all samples. CONCLUSIONS AND CLINICAL RELEVANCE: In horses with orthopedic infections, RILP of enrofloxacin (1.5 mg/kg) should be considered as a treatment option. However, care must be taken during administration. A dose of amikacin > 250 mg is recommended to attain effective tissue concentrations via RILP in standing horses.  相似文献   
35.
The association between high malting quality and pre-harvest sprouting (PHS) susceptibility is a key challenge when developing new malting barley varieties. A new malting barley variety Baudin has successfully combined high malting quality and PHS tolerance. A doubled haploid population was developed for mapping PHS tolerance and seed dormancy from a cross of Baudin?×?AC Metcalfe using 233 molecular markers. Three QTLs were mapped for seed dormancy based on the standard germination test at 24, 48 and 72?h. One major QTL was mapped to the long arm of chromosome 5H controlling seed dormancy and PHS tolerance from Baudin. Two other minor QTLs were identified from Baudin on chromosomes 3 and 7H. QTL/QTL interaction was detected for seed dormancy between chromosomes 3 and 5H. The PHS tolerance allele of the 5H QTL from Baudin contributes to higher malt yield without significant impact on diastatic power, beta-glucan content and wort viscosity. QTL from Baudin provide new sources to integrate PHS tolerance and high malting quality.  相似文献   
36.
The challenges of reusing mining and mineral-processing wastes   总被引:2,自引:0,他引:2  
Mining and mineral-processing wastes are one of the world's largest chronic waste concerns. Their reuse should be included in future sustainable development plans, but the potential impacts on a number of environmental processes are highly variable and must be thoroughly assessed. The chemical composition and geotechnical properties of the source rock determine which uses are most appropriate and whether reuse is economically feasible. If properly evaluated, mining waste can be reused to reextract minerals, provide additional fuel for power plants, supply construction materials, and repair surface and subsurface land structures altered by mining activities themselves.  相似文献   
37.
Objective-To evaluate whether dogs undergoing splenectomy had an increased risk of gastric dilatation-volvulus (GDV), compared with a control group of dogs undergoing enterotomy. Design-Retrospective case-control study. Animals-219 dogs that underwent splenectomy for reasons other than splenic torsion (splenectomy group; n = 172) or enterotomy (control group; 47) without concurrent gastropexy. Procedures-Medical records were reviewed for information on signalment, date of surgery, durations of surgery and anesthesia, reason for splenectomy, histopathologic findings (if applicable), whether gastropexy was performed, duration of follow-up, and date of death (if applicable). Follow-up information, including occurrence of GDV, was obtained via medical records review and a written client questionnaire. Results-Reasons for splenectomy included splenic neoplasia, nonneoplastic masses, infarction, traumatic injury, and adhesions to a gossypiboma. Incidence of GDV following surgery was not significantly different between dogs of the splenectomy (14/172 [8.1 %]) and control (3/47 [6.4%]) groups. Median time to GDV for the 17 affected dogs was 352 days (range, 12 to 2,368 days) after surgery. Among dogs that underwent splenectomy, sexually intact males had a significantly higher incidence of GDV (4/16) than did castrated males and sexually intact or spayed females (10/156). Incidence of GDV among sexually intact male dogs did not differ between groups. Conclusions and Clinical Relevance-Results did not support a recommendation for routine use of prophylactic gastropexy in dogs at the time of splenectomy. Other patient-specific risk factors should be assessed prior to recommending this procedure.  相似文献   
38.
Objective The aim of this study was to perform a retrospective review of parotid duct transposition (PDT) in the dog to determine the rate and nature of complications, the success and failure rates and to evaluate owner satisfaction. Methods Medical records of 56 dogs (92 eyes) that underwent PDT and subsequent follow‐up by a veterinary ophthalmologist were reviewed. Forty owners (40 dogs/66 eyes) were contacted by telephone and 37 owners (37 dogs/60 eyes) also completed a visual analog scale questionnaire. Statistical evaluation included Wilcoxon Signed Rank tests, one‐way analysis of variance and Kaplan–Meier survival analysis with Wilcoxon and Log‐rank tests. Results The mean follow‐up was 38.7 months (range 1–109 months). The surgical success rate was 92% (85/92 eyes). Total failures (8%, 7/92 eyes) were because of severe saliva intolerance (n = 5 eyes) and PDT failure (n = 2 eyes). The complication rate was 50% (46/92 eyes) of which 61% (28/46 eyes) were managed medically and 39% (18/46 eyes) required further surgery. Ninety percent (36/40) of owners indicated that they would proceed with surgery again. Statistically significant improvements in owner perception of ocular comfort, number of daily topical treatments, ocular wetness, and postoperative vision were identified. Conclusions This study shows that PDT is a successful procedure based on clinical findings and in terms of owner perception. It has also demonstrated that PDT improves ocular comfort and vision in medically refractive cases of keratoconjunctivitis sicca, and that a low level of on‐going management is required in 33% of cases.  相似文献   
39.
40.
Inflammatory colorectal polyps (ICRPs) in miniature dachshunds are recently recognized as a major cause of large bowel diarrhea in this dog breed in Japan. ICRPs are characterized by the formation of multiple small polyps and a space-occupying large polyp in the colorectal area, and are thought to be a novel form of inflammatory bowel disease (IBD). In humans, specific cytokine patterns attributed to T helper (Th)1, Th17 and regulatory T cells have important roles in the pathogenesis of IBD. Thus, the aim of the present study was to assess the gene expression of cytokines of T cell subsets in the colorectal mucosa from dogs with ICRPs. Colorectal mucosal specimens from 10 dogs with ICRPs and 14 control dogs were used in this study. Interferon (IFN)-γ, interleukin (IL)-4, IL-17A and IL-10 mRNA expression was assessed using quantitative real-time PCR. IL-17A mRNA expression was significantly increased in large polyps compared to small polyps and controls. IFN-γ and IL-10 mRNA expression in large polyps were significantly higher than in controls. There was no significant difference in IL-4 mRNA expression among the three groups. IL-17A is thought to play important roles in the pathogenesis of ICRPs. IL-10 up-regulation could oppose the proinflammatory function of IL-17A.  相似文献   
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