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211.
Verticillium wilt of olive (VWO) is probably the most devastating fungal disease for olive trees worldwide, and currently the main cultivars are susceptible or moderately susceptible to this disease. The evaluation of resistant cultivars as rootstocks to control the disease has scarcely been explored, and mainly in short-term studies under controlled conditions, which usually do not correspond with field evaluations. The main objective of this study was to assess the responses to VWO of different scion × rootstock combinations of the olive cultivars Picual, Arbequina, Changlot Real, and Frantoio in a long-term field experiment with a soil highly infested with the defoliating pathotype of Verticillium dahliae. The results showed that grafting the susceptible cultivar Picual onto resistant rootstocks delayed the onset of the disease symptoms; however, after 4 years, it was observed that all combinations that contain Picual (a) were extensively colonized by V. dahliae; (b) developed severe symptoms of the disease; and (c) had plant mortality similar to Picual growing on its own roots. This result highlights the importance of long-term field experiments to evaluate VWO and shows that grafting susceptible olive cultivars onto resistant ones does not provide a durable control of VWO under high inoculum potential, as V. dahliae is able to progress through the resistant rootstock and then extensively colonize and kill the susceptible scion. However, the high inoculum potential observed in this study does not allow us to consider the evaluated resistant cultivars as completely ineffective under lower inoculum densities.  相似文献   
212.
European Journal of Plant Pathology - Huanglongbing (HLB), associated with the proteobacterium ‘Candidatus Liberibacter asiaticus’(CLa), is a destructive disease in citrus....  相似文献   
213.
A 7-year-old thoroughbred stallion presented with severe colic, which was resolved surgically. On postsurgical palpation and rectal ultrasonography, the left seminal vesicle was enlarged, the left testicle and epididymis showed signs of inflammation with hydrocele. Antibiotics and anti-inflammatory treatment were administered. Fever and colic syndrome recurred, with severe inflammation of the left testis and epididymis, and unilateral orchiectomy was performed. Histopathological diagnosis confirmed chronic orchioepididymitis, and Klebsiella pneumoniae was identified and typed from all cultures. At breeding soundness examination 2 months after treatment with ceftiofur, K. pneumoniae was again isolated, and cytology revealed degenerated polymorphonuclear cells and red blood cells. Transurethral endoscopic examination was used to locate the infection in the left seminal vesicle, and ticarcillin-clavulanic was locally infused for 10 days. Nevertheless, the pathogen was once again isolated in the ejaculate, and the affected seminal vesicle was again treated locally for 5 consecutive days, using imipenem-cilastatin, a new antibiotic showing high sensitivity. Follow-up breeding soundness examination revealed an improvement in seminal characteristics and no pathogen isolation. Total pregnancy rate (31 of 36; 86%) and first cycle pregnancy rate (18 of 36; 50%) in the last breeding season reached levels similar to those prior to infection (65 of 82; 80% and 47 of 82; 57% respectively), suggesting that local treatment with imipenem-cilastatin in stallions with seminal vesicle infections is effective and, in this case, did not produce any adhesions or other undesirable effects, permitting the stallion to resume breeding with no apparent deleterious effect on fertility despite having only one testicle.  相似文献   
214.
Ketorolac (KET) is a nonsteroidal anti-inflammatory drug for human use, with a potent analgesic activity, that is used in the relief of moderate-to-severe postoperative pain. The pharmacokinetics of KET tromethamine was evaluated after single IV injection at 0.5 mg/kg body weight, after intubation and 10 minutes before surgery, to six Arabian colts undergoing orchiectomy. Intraoperative cardiorespiratory variables were monitored. Blood samples were collected for 36 hours, and serum samples were analyzed by high performance liquid chromotography with ultraviolet-visible detection. During surgery, all monitored physiological parameters were stable. Intermittent positive pressure ventilation, and normocapnia were maintained throughout the procedure in all animals. No adverse effects were observed. The kinetics of KET was described by a two-compartment models, and also a noncompartmental analysis was performed. The distribution and elimination half-lives were t1/2λ1t1/2λ1 0.06 ± 0.02 and t1/2λ2t1/2λ2 0.59 ± 0.21 hours, respectively. Body clearance and mean residence time were 339.99 ± 120.19 mL/h/kg and 0.49 ± 0.22 hours, respectively. The volume of distribution at steady state and volume of distribution based on the terminal phase were 218.83 ± 134.26 mL/kg and 522.5 ± 529.3 mL/kg, respectively. The serum protein binding was 75.8 ± 2.9%. The results indicate that KET at 0.5 mg/kg IV was very rapidly eliminated and thus was likely not effective in the postoperative period. However, further studies including a control group and at higher doses are suggested to investigate the KET kinetics and the analgesic efficacy in horse and define the most appropriate dosage scheme.  相似文献   
215.
An 8-year-old, 4 kg, intact female, domestic shorthaired cat was referred for tachypnea and pleural effusion. A 24-h Holter recording showed numerous polymorphic ventricular premature complexes with left and right bundle branch block morphology. Echocardiographic examination revealed right atrial and ventricular dilation. The right ventricular free wall was thin and aneurysmal. The cat died 10 days after initiation of antiarrhythmic therapy. Gross and histopathological findings were consistent with arrhythmogenic right ventricular cardiomyopathy (ARVC) associated with severe left ventricular involvement.  相似文献   
216.
217.
ABSTRACT Effects on penetration and hypersensitive resistance of the cinnamyl acid dehydrogenase (CAD) suicide inhibitor ([(2-hydroxyphenyl) amino] sulphinyl) acetic acid, 1.1 dimethyl ester, which suppresses phenylpro-panoid biosynthesis, and of D-mannose, which sequesters phosphate and reduces energy available in host cells, were studied in faba bean (Vicia faba) genotypes with differing resistance mechanisms to faba bean rust (Uromyces viciae-fabae). Inhibition of CAD reduced penetration resistance in lines 2N-34, 2N-52, V-1271, and V-1272, revealing an important role for phenylpropanoid biosynthesis in the resistance of these lines. Inhibition of CAD also inhibited hypersensitive cell death in these lines. D-mannose had little or no effect on resistance. By contrast, CAD inhibition did not affect penetration resistance of line BPL-261, which has a high degree of penetration resistance not associated with hypersensitive cell death. In BPL-261, D-mannose inhibited penetration resistance. The parallelism between the faba bean genotype responses to rust observed here and the response of barley genotypes with differing resistance mechanisms to powdery mildew after similar inhibitor treatments is analyzed and discussed.  相似文献   
218.
Chocolate and other cocoa-containing products are a rich source of polyphenols. This paper describes an ultra-performance liquid chromatography (UPLC) method that can separate and quantify in 3 min six of the major chocolate polyphenols: catechin; epicatechin; B2 (epicatechin-4beta-8-epicatechin); B5 (epicatechin-4beta-6-epicatechin); C1 (epicatechin-4beta-8-epicatechin-4beta-8-epicatechin); and tetramer D (epicatechin-4beta-8-epicatechin-4beta-8-epicatechin-4beta-8-epicatechin). A survey of 68 chocolate samples indicated that there was a strongly predictive relationship between epicatechin and the other individual polyphenols, especially procyanidin B2 (R 2 = 0.989), even though the chocolates came from varied sources and manufacturers. The relationship was less strong with catechin, and so further work to explore the reasons for this difference was performed. Chiral analysis on a subset of 23 chocolates showed that (-)-epicatechin had a predictive relationship with (+)-catechin in line with the other polyphenols, but not with (-)-catechin (the predominant form). This indicates that (-)-catechin is the most affected by manufacturing conditions, possibly formed through epimerization from (-)-epicatechin during processing. The results show that epicatechin concentrations can be used to predict the content of other polyphenols, especially B2 and C1, and total polyphenols content. Finally, the (-)-catechin content is not predictable from the epicatechin content, and it is concluded that this is the main form of polyphenol that varies according to manufacturing conditions and cocoa origin.  相似文献   
219.
Prats E  Llamas MJ  Rubiales D 《Phytopathology》2007,97(9):1049-1053
ABSTRACT In this work, we studied the resistance of 277 Medicago truncatula accessions against powdery mildew and further characterized the defense mechanisms of resistant plants. Ten resistant accessions were selected according to macroscopic assessment. Histological studies showed a range of defense mechanisms, acting alone or combined, that impeded fungal development at different stages. Some accessions allowed a reduced spore germination frequency compared with that of the susceptible control. In others, the fungus was arrested at penetration stage due to papilla formation. Epidermal cells of several accessions were penetrated by the fungus but then hypersensitive response (HR) leading to cell death hampered fungal development. In some cases, cell death was very fast and no haustorium could be observed in epidermal cells, whereas in others, haustoria and secondary hyphae indicated a slow HR. Finally, in some accessions in which no HR was observed, colony growth was restricted through posthaustorial defense mechanisms. Characterization of defense mechanisms will be useful for further cellular and molecular studies to unravel the bases of resistance in this species in particular and in legume-powdery mildew interaction in general.  相似文献   
220.
Renal dysplasia is defined as a condition of disorganised development of renal parenchyma due to abnormal differentiation. The case of a 5-month-old intact male Norwegian Forest Cat with a history of polyuria and polydipsia is reported. Ultrasonographic examination showed a slight enlargement of kidneys. Biochemical parameters, haematological examinations and clinical signs were compatible with chronic renal failure (CRF). Histological examination was correlated with a primary tubular disorganisation and modification of glomerular compartment. The clinical history together with the histological lesions is consistent with bilateral juvenile renal dysplasia in this cat. To our knowledge, feline renal dysplasia has been reported in fetal infections with panleukopenia virus; no reports indicate the idiopathic origin in feline dysplastic lesions.  相似文献   
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