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1.
A study was conducted to evaluate a non-destructive method able to predict Magness–Taylor (MT) penetrometric firmness of blood oranges, potentially applicable for on-line selection. The method consisted of multivariate modelling of non-destructive penetrometric measurements performed on intact oranges with a 11.3 mm diameter probe by digital dynamometric equipment. The tests were carried out on 366 blood oranges (Citrus sinensis (L.) Osbeck cv. Tarocco); 60 were used as a control group to verify the non-destructive nature of the tests. Four test factors were used on the fruit: two different levels of non-destructive deformation (1 and 3 mm), at two different deformation speeds (5 and 30 mm s?1). In order to obtain the reference parameter (MT firmness), a destructive penetrometric test followed each non-destructive deformation on the same fruit (deformation of 20 mm at 1 mm s?1). The force–deformation curves of the non-destructive tests were elaborated to calculate different texture parameters (max force, elasticity, work). These parameters with raw curve data (force values for constant deformation steps) were used, after autoscaling pre-processing, as X-block datasets in supervised multivariate modelling (partial least squares) to predict MT firmness values. Among the test factors used, the 30 mm s?1 speed and 3 mm deformation provided the best overall prediction of MT firmness. This comprised an r value of 0.76 and standard error of prevision (SEP) of 2.99 N for a MT firmness mean value of 35.65 N (8.4%). The time needed to apply the selected deformation may lead to a sorting speed of about 10 fruit per second, representing an acceptable value for commercial application.  相似文献   
2.
Gender determination is frequently requested by reptile breeders, especially for species with poor or absent sexual dimorphism. The aims of the current study were to describe techniques and diagnostic sensitivities of ultrasound, radiography, and computed tomography for gender determination (identification of hemipenes) in four species of lizards. Nineteen lizards of known sex, belonging to four different species (Pogona vitticeps, Uromastyx aegyptia, Tiliqua scincoides, Gerrhosaurus major) were prospectively enrolled. With informed owner consent, ultrasound, noncontrast CT, contrast radiography, and contrast CT (with contrast medium administered into the cloaca) were performed in conscious animals. Imaging studies were reviewed by three different operators, each unaware of the gender of the animals and of the results of the other techniques. The lizard was classified as a male when hemipenes were identified. Nineteen lizards were included in the study, 10 females and nine males. The hemipenes were seen on ultrasound in only two male lizards, and appeared as oval hypoechoic structures. Radiographically, hemipenes filled with contrast medium appeared as spindle‐shaped opacities. Noncontrast CT identified hemipenes in only two lizards, and these appeared as spindle‐shaped kinked structures with hyperattenuating content consistent with smegma. Hemipenes were correctly identified in all nine males using contrast CT (accuracy of 100%). Accuracy of contrast radiography was excellent (94.7%). Accuracy of ultrasound and of noncontrast CT was poor (64.3% and 63.1%, respectively). Findings from the current study supported the use of contrast CT or contrast radiography for gender determination in lizards.  相似文献   
3.
Carcinomas represent two‐thirds of canine nasosinal neoplasms. Although radiation therapy (RT) is the standard of care, the incidence of local recurrence following treatment is high. Cyclooxygenase‐isoform‐2 (COX‐2) is expressed in 71–95% of canine nasal carcinomas and has been implicated in tumor growth and angiogenesis. Accordingly, COX‐2 inhibition seems rational to improve outcome. Dogs with histologically confirmed, previously untreated nasal carcinomas were randomized to receive the combination of a selective COX‐2 inhibitor (firocoxib) and palliative RT (Group 1) or RT and placebo (Group 2). Patients were regularly monitored with blood tests, urinalysis, and computed tomography. Pet owners were asked to complete monthly a quality‐of‐life questionnaire. Twenty‐four dogs were prospectively enrolled. According to Adams modified system, there were five stage 1, five stage 2, three stage 3, and 11 stage 4 tumors. Two dogs had metastases to regional lymph nodes. Median progression‐free interval and overall survival were 228 and 335 days in Group 1 (n = 12) and 234 and 244 days in Group 2 (n = 12). These differences were not statistically significant. The involvement of regional lymph nodes was significantly associated with progression‐free interval and overall survival (P = 0.004). Quality of life was significantly improved in Group 1 (P = 0.008). In particular, a significant difference was observed for activity and appetite. Although not providing a significant enhancement of progression‐free interval and overall survival, firocoxib in combination with RT is safe and improved life quality in dogs with nasal carcinomas.  相似文献   
4.
Journal of Pest Science - Longhorn beetles are commonly moved among continents within wood packaging materials used in trades. Visual inspections carried out at points of entry often fail to detect...  相似文献   
5.
A 7-year-old dog was presented with a history of an open lesion on the right thoracic wall, discharging honey-like fluid and small stones. Ultrasonography and computed tomographic fistulography identified a cholecystocutaneous fistula; cholecystectomy was curative. Veterinarians should consider this disease in patients with long-term discharging lesions on the right thoracic or abdominal wall.  相似文献   
6.
7.
Over the past decade microsatellites or simple sequence repeats (SSRs) have attracted a considerable amount of attention from researchers. The aim of the present paper was to analyse expressed sequence tag-derived SSR (EST-SSR) marker variability in wheat and to investigate the relationships between the number and type of repeat units and the level of microsatellite polymorphism. Two hundred and forty-one new EST-SSR markers available in a public database () were characterized in eight durum wheat cultivars (Svevo, Ciccio, Primadur, Duilio, Meridiano, Claudio, Latino, Messapia), two accessions of Triticum turgidum var. dicoccoides (MG4343, MG29896), one accession of T. turgidum var. dicoccum (MG5323) and in the common wheat cv. Chinese Spring. Of these, 201 primer pairs (83.4%) amplified PCR products successfully, while the remaining 40 (16.6%) failed to amplify any product. Of the EST-SSRs analysed, 45.2% of the primer pairs amplified one or two PCR products. Multiple discrete PCR products were observed among both di- and trinucleotide EST-SSR markers (31.2 and 40.5%, respectively). Markers based on dinucleotide microsatellites were more polymorphic than those based on trinucleotide SSRs in the 12 wheat genotypes tested (68.9 and 52.7%, respectively). An average of 2.5 alleles for dinucleotide and 2.0 alleles for trinucleotide SSRs was observed. The data reported in the present work indicate the presence of a significant relationship between motif sequence types and polymorphism. The primer set based on the AG repeat motif showed the lowest percentage of polymorphism (55.0%), while the primer set based on the AC repeat motif showed t he highest percentage (85.0%). Among trinucleotide SSRs, the AGG microsatellite markers showed the highest percentage of polymorphism (70.0%), and the ACG motif the lowest value (25.0%). The characterization of these new EST-SSR markers and the results of our studyon the effect of repeat number and type of motifs could have important applications in the genetic analysis of agronomically important traits, quantitative trait locus discovery and marker-assisted selection.  相似文献   
8.
Experiments were carried out to investigate, under controlled conditions, the effects of acid smut emitted by oil-fired power plants. The foliar response of 31 selected plant species was ranked and marked differences in sensitivity were observed. Anatomical features of the foliar lesions were described. The toxicity of smuts was largely dependent on their acidity and size. Toxicity was related to temperature but was completely independent of relative humidity in the range from 50 to 90%. No interactive effects were observed between acid smuts and some commercial fungicides, or treatments with asymptomatic concentrations of So2 in fumigation chambers. Some growth parameters were negatively affected by acid smuts in radish.  相似文献   
9.
Evidence for ozone formation in human atherosclerotic arteries   总被引:1,自引:0,他引:1  
Here, we report evidence for the production of ozone in human disease. Signature products unique to cholesterol ozonolysis are present within atherosclerotic tissue at the time of carotid endarterectomy, suggesting that ozone production occurred during lesion development. Furthermore, advanced atherosclerotic plaques generate ozone when the leukocytes within the diseased arteries are activated in vitro. The steroids produced by cholesterol ozonolysis cause effects that are thought to be critical to the pathogenesis of atherosclerosis, including cytotoxicity, lipid-loading in macrophages, and deformation of the apolipoprotein B-100 secondary structure. We propose the trivial designation "atheronals" for this previously unrecognized class of steroids.  相似文献   
10.
Objective – To compare the determination of cardiac output (CO) via arterial pulse pressure waveform analysis (FloTrac/Vigileo) versus lithium dilution method. Design – Prospective study. Setting – University teaching hospital. Animals – Six adult dogs. Interventions – Dogs were instrumented for CO determinations using lithium dilution (LiDCO) and FloTrac/Vigileo methods. Direct blood pressure, heart rate, arterial blood gases, and end‐tidal isoflurane (ETIso) and CO2 concentrations were measured throughout the study while CO was manipulated with different depth of anesthesia and rapid administration of isotonic crystalloids at 60 mL/kg/h. Measurements and Main Results – Baseline CO measurements were obtained at 1.3% ETIso and were lowered by 3% ETIso. Measurements were obtained in duplicate or triplicate with LiDCO and averaged for comparison with corresponding values measured continuously with the FloTrac/Vigileo method. For 30 comparisons between methods, a mean bias of ?100 mL/kg/min and 95% limits of agreement between ?311 and +112 mL/kg/min (212 mL/kg/min) was determined. The mean (mL/kg/min) of the differences of LiDCO?Vigileo=62.0402+?0.8383 × Vigileo, and the correlation coefficient (r) between the 2 methods 0.70 for all CO determinations. The repeatability coefficients for the individual LiDCO and FloTrac/Vigileo methods were 187 and 400 mL/kg/min, respectively. Mean LiDCO and FloTrac/Vigileo values from all measurements were 145 ± 68 mL/kg/min (range, 64–354) and 244 ± 144 mL/kg/min (range, 89–624), respectively. The overall mean relative error was 48 ± 14%. Conclusion – The FloTrac/Vigileo overestimated CO values compared with LiDCO and the relative error was high, which makes this method unreliable for use in dogs.  相似文献   
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