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911.
Meindert D. De Jong Patricia S. Wagenmakers J. Goudriaan 《European journal of plant pathology / European Foundation for Plant Pathology》1991,97(1):55-61
Chondrostereum purpureum is being developed as a microbial herbicide to controlPrunus serotina in coniferous forests. After biological control, the fungus produces basidiospores that may reach and infect non-target plants. As part of a risk analysis, spore escape from a forest was quantified. For this purpose, a stratified model was developed for a forest of 250 m with 250 m. A turbulent diffusion equation was used to describe spore fluxes for each layer.In a simple calculation procedure, the spore fluxes for the different layers were calculated simultaneously. The downwind escape fraction was found to vary from 0.19 to 0.45, and the upward escapte fraction from 0.07 to 0.23. These escape fractions increased with increasing wind speed.Number of spores released from basidiocarps, and escape fractions could be used as inputs for a Gaussian plume model to calculate spore immission into orchards. 相似文献
912.
Flavonoids are important dietary constituents owing to their health-promoting properties. As a result, simplified analytic techniques are required for the population of databases with food values so that associations between dietary intake and disease risk/incidence can be established. The current research provides a simplified sample preparation procedure for the accurate estimation of food anthocyanidins, flavones, and flavonols as aglycons. Traditionally, flavonoid aglycons have been formed by acidic hydrolysis. However, some flavonoid aglycons are slowly degraded by acid. A procedure has been developed whereby anthocyanidins and flavonols are deglycosylated with HCl in 50% aqueous methanol and the resulting aglycons subsequently quantified by application of pseudo-first-order kinetics to their degradation. Flavones are also deglycosolated under similar conditions but, at appropriate temperatures, their aglycons are stable in acid, so kinetics were not required for the quantitation of this subclass of flavonoids. Catechins and flavanones were rapidly degraded under the hydrolytic conditions used in these studies. 相似文献
913.
M. Beecher D. Hennessy T.M. Boland M. McEvoy M. O'Donovan E. Lewis 《Grass and Forage Science》2015,70(1):19-29
914.
Sung-Hoon Park Noton Kumar Dutta Min-Won Baek Dong-Jae Kim Yi-Rang Na Seung-Hyeok Seok Byoung-Hee Lee Ji-Eun Cho Geon-Sik Cho Jae-Hak Park 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(2):141-146
The effect of NaCl plus 3% chitosan on the systolic blood pressure of spontaneously hypertensive rats (SHR) were evaluated and compared with NaCl plus KCl (NaCl, 49.36% + KCl 49.36%) and chitosan or NaCl treatment alone. In SHR, administration of NaCl plus chitosan (44 mM Na/day) for two months significantly decreased the systolic blood pressure greater than of NaCl plus KCl and NaCl alone. NaCl plus chitosan resulted, though not statistically significant, in decreased urinary Na+ excretion and decreased blood urea nitrogen levels. Urinary creatinine of NaCl plus chitosan was slightly decreased compared to 3 treated groups. Serum electrolytes levels, however, remained unchanged. The combination of NaCl and chitosan may be superior to the conventional use of NaCl plus KCl or NaCl alone in the prevention of hypertension. Even though these supplementary diets have demonstrated potential anti-hypertensive effects in the experimental animal model, further research is needed before any recommendations can be made. 相似文献
915.
Joshua J. Smith DVM Daniel J. Fletcher PhD DVM DACVECC Stacy D. Cooley DVM DACVR Margret S. Thompson DVM DACVR 《Journal of Veterinary Emergency and Critical Care》2018,28(1):31-38
Objective
To develop a reference range for ultrasonographically measured optic nerve sheath diameter (ONSD‐US) in dogs. We hypothesized that ONSD‐US can be measured reliably and is associated with weight but not age, sex, or body condition score (BCS), and that the relationship between weight and ONSD‐US in dogs is allometric due to canine size variations.Design
Prospective, observational study.Setting
University teaching hospital.Animals
Seventy‐eight healthy adult dogs.Interventions
The ONSD was measured by a standardized transpalpebral approach.Measurements and Main Results
Regression analysis showed the relationship between weight and ONSD was better fit with a linear model (R2 = 0.8510) than an allometric model (R2 = 0.7917). Multiple regression analysis showed ONSD is associated with weight (P < 0.0001), age (P = 0.0021), and BCS (P = 0.0007), but not with sex. Dominance analysis showed 94.6% of the variance explained by the model was due to weight. Intraclass correlation coefficient (ICC) analysis showed excellent interobserver (ICC = 0.9338–0.9608) and intraobserver (ICC = 0.9893) reliability.Conclusions
These results suggest that ONSD‐US may be reliably measured in dogs using our described transpalpebral approach, and we have calculated prediction intervals based on body weight. Future studies are needed to determine if ONSD‐US measurements are associated with intracranial hypertension as shown in human medicine. 相似文献916.
David A. Lidbetter BVSc MVS CertSAS MACVSc MRCVS Fred A. Williams Jr. DVM Diplomate ACVS D. J. Krahwinkel DVM MS Diplomate ACVS ACVA ACVECC William H. Adams DVM Diplomate ACVR 《Veterinary surgery : VS》2002,31(1):57-64
OBJECTIVE: To describe and evaluate a technique for radical resection of the lateral body wall for treatment of fibrosarcoma with reconstruction using polypropylene mesh and a caudal superficial epigastric axial pattern flap in cats. STUDY DESIGN: Prospective, clinical study. ANIMALS OR SAMPLE POPULATION: Six client-owned cats with fibrosarcoma. METHODS: Six cats with histologically confirmed fibrosarcoma of the lateral body wall were staged using radiography and/or computer tomography scanning. Preoperative radiotherapy was used in 3 cats. All cats had the lateral abdominal wall resected and reconstructed with polypropylene mesh. A caudal superficial epigastric flap was mobilized and rotated to close the skin deficit. The animals were evaluated after surgery for wound complications, tumor recurrence, and metastasis. Outcome was assessed by patient examination and client consultation. RESULTS: Minor dehiscence of the skin flaps occurred in 2 cats, and 1 other cat was successfully resuscitated from respiratory and cardiac arrest after surgery. All tissue specimens were tumor-free at the surgical margins. Follow-up times ranged from 12 to 21 months, with a mean time of 17.2 months. None of the cats had evidence of local tumor recurrence or metastasis; outcome was judged good to excellent in all cats. CONCLUSIONS AND CLINICAL RELEVANCE: Radical lateral body-wall resection and reconstruction is an effective technique for achieving local tumor control with acceptable patient morbidity. Further studies are needed to assess whether the technique will result in improved tumor-free intervals and survival times. 相似文献
917.
Luis Alvarez-Lajonchegre Vinicius R. Cerqueira Israel D. Silva Jaqueline Araujo Marcosdos Reis 《Journal of the World Aquaculture Society》2002,33(4):506-516
A pilot‐scale trial to rear fat snook Centropomus parallelus through larval, weaning and nursery phases was conducted in Florianópolis, Brazil. Eggs (96% fertilization) from captive broodstock, induced to spawn using 50 μg/kg LHRHa were stocked in two 4,000‐L cylindrical fiberglass tanks at a mean density of 19.2 eggs/L. Nannochloropsis oculata was stocked with the eggs and maintained at a mean density of 0.5–1.0 ± 106 cells/mL up to 31 dph (31 dph). Hatching averaged 90%. Larvae were fed rotifers Brachionus rotundiformis enriched with an oil emulsion from 3 dph to 36 dph (30–40 rotifers/mL) and Artermia meta‐nauplii enriched with Selco from 22 dph to 60 dph (mean 2.9 meta‐nauplii/mL). Weaning began at 45 dph with an artificial dry diet NRG (50% protein), supplied together with concentrated and enriched Artemia meta‐nauplii. No critical period of mortality was observed during larval rearing. During the 43 days of weaning and nursery, less than 1% mortality was recorded. Food conversion rate during nursery was 1.17, with a change in the coefficient of variation of mean total length of 1.3%. Specific total growth rate in weight was 13.0 %/d and mean growth in total length and total weight were 0.65 mm/d and 24.0 mg/d over the whole rearing trial respectively. Mean total length and total weight of juveniles were 57.6 ± 0.1 mm and 2.11 ± 0.12 g, respectively, and the length‐weight relationship was W = 8.29931 ± 10–5 TL3.049607 (r= 0.9986). on 88 dph when the trial was terminated. The condition factor on 88 dph was 1.104. On 88 dph a total of 35,000 juveniles were harvested, overall survival was 25.5% with mean final density of 4.4 fishn and biomass of 6.9 kg/m3. The present trial demonstrated the feasibility of mass production of fat snook. Possible improvements necessary for commercial cultivation of fat snook C. parallelus are discussed. 相似文献
918.
C. C. Hole R. L. K. Drew B. M. Smith D. Gray 《The Journal of Horticultural Science and Biotechnology》2013,88(5):651-657
SummaryCarrot roots from a range of environments, developmental stages and cultivars showed variation in splitting susceptibility from 3.8% to 72.5%. Estimates of tissue tensile strength, fracture toughness and residual strain for roots from these sources were not related to estimates for damage. The measurement of release of intrinsic stress from whole-root sections showed some relationship with damage in that the most susceptible cultivars also displayed greater release of stress. These same varieties had larger storage cells in their outer parenchyma. Developmental variation in tissue strength induced by different sowing dates and years was inconsistent between years. Increases in strength of root tissue with advancing date during the autumn observed in field experiments, were not related to temperature changes imposed in controlled environment. Variation in water and solute potentials was generally greater than variation in turgor potential, which remained well conserved in all experiments. Fracture toughness, which is dependent on tissue water status, was not well related to turgor in these experiments. 相似文献
919.
920.
A powerful aromatic volatile thiol, 2-furanmethanethiol, exhibiting roast coffee aroma in wines made from several Vitis vinifera grape varieties 总被引：2，自引：0，他引：2
Tominaga T Blanchard L Darriet P Dubourdieu D 《Journal of agricultural and food chemistry》2000,48(5):1799-1802
The chemical compound 2-furanmethanethiol (2FM), with a strong roast coffee aroma, has been identified in sweet white wines made from the Petit manseng grape variety, and in certain red Bordeaux wines (made from the Merlot, Cabernet franc, and Cabernet sauvignon grape varieties). This was done by extracting specific volatile thiols using p-hydroxymercuribenzoate. The 2FM has also been found in toasted oak used in barrel-making. All the Petit manseng sweet white wines and some of the red Bordeaux wines analyzed contained between a few ng/L and several dozen ng/L of 2FM. Taking into account its very low perception threshold (0.4 ng/L in a model hydro alcoholic environment), 2FM could therefore contribute to the roast coffee aroma of certain wines. 相似文献