The aim of this study was to assess whether regular consumption of cranberry juice results in elevations in urinary salicylate concentrations in persons not taking salicylate drugs. Two groups of healthy female subjects (11/group) matched for age, weight, and height consumed 250 mL of either cranberry juice or a placebo solution three times a day (i.e., 750 mL/day) for 2 weeks. At weekly intervals, salicylic acid and salicyluric acid (the major urinary metabolite of salicylic acid) concentrations were determined in urine by HPLC with electrochemical detection. Concentrations of salicylic acid in plasma were also determined. Consumption of cranberry juice was associated with a marked increase (p < 0.001) of salicyluric and salicylic acids in urine within 1 week of the intervention. After 2 weeks, there was also a small but significant (p < 0.05) increase in salicylic acid in plasma. The regular consumption of cranberry juice results in the increased absorption of salicylic acid, an anti-inflammatory compound that may benefit health. 相似文献
The contributions of soil variables to the variations in the yields of cassava (Manihot esculenta), yam (Dioscorea rotundata), maize (Zea mays) and pigeon pea (Cajanus cajan) were evaluated over 2 years in this study. The data were from three replicates of two randomized complete block design experiments sited in a newly cleared forest and on previously cultivated land both in Nsukka, eastern Nigeria. The 28 soil physicochemical properties and six crop yield parameters measured were partitioned between location and year before applying a stepwise regression procedure to analyze them.
The study showed that soil variables accounted for >70% of the variation in cassava root yields and harvest index. Both soil physical and chemical properties contributed but the former (particularly macroporosity, microporosity, total porosity and bulk density) contributed most. Selected soil variables also accounted for >70% of the variation in yam tuber yield and shape index of tubers especially in 1998. In both crop years chemical properties appeared to dominate over the physical ones. Soil variables accounted for between 51 and 99% of the variation in maize grain and stover yields. The only exception was the figure of 44% obtained at the forest location in 1998. Soil pH, total exchangeable acidity and microporosity were particularly important contributors to the variations in both maize yield parameters. The contributions of soil variables to pigeon pea yield parameters were low (<50%) except in 1999 at the forest location where seven soil variables accounted for over 85% variation in seed yield.
It was obvious generally from the study that soil variables were important determinants of yield variations in the four crops. It was also shown that physical properties should always be included in this kind of analysis. Also the number of soil variables which were of significance generally increased when the level of soil properties was low, as was the case with the cultivated site versus forest site, and 1999 versus 1998 analysis. Thus increasing the number of soil variables used and partitioning them into more homogeneous units helped to improve the results obtained using the procedure. 相似文献
Infrared spectra of material captured from comet 81P/Wild 2 by the Stardust spacecraft reveal indigenous aliphatic hydrocarbons similar to those in interplanetary dust particles thought to be derived from comets, but with longer chain lengths than those observed in the diffuse interstellar medium. Similarly, the Stardust samples contain abundant amorphous silicates in addition to crystalline silicates such as olivine and pyroxene. The presence of crystalline silicates in Wild 2 is consistent with mixing of solar system and interstellar matter. No hydrous silicates or carbonate minerals were detected, which suggests a lack of aqueous processing of Wild 2 dust. 相似文献
It is well understood that insufficient oxygen within plant root zones can greatly diminish plant productivity. However, little is known about the effect of elevated root zone oxygen concentrations. Tomato (Lycopersicon lycopersicum Mill., cv. Trust) seedlings were grown in nutrient solutions containing dissolved oxygen (DO) concentration ranging from 5.3 to 40 mg L−1 for 4 weeks. There were no visible symptoms observed on the leaves or stems in any of the treatments. Leaf chlorophyll content was higher in the 40 mg L−1 treatment than with 20 and 30 mg L−1 DO treatments. Two weeks from the start of the experiment, roots in the 40 mg L−1 treatment exhibited stunted growth, became thicker, and had fewer side and fine roots compared to roots in the lower levels of DO treatment. Almost all the measured growth parameters (fresh and dry weights of root, stem, and leaf, leaf area, stem diameter) were significantly reduced in plants grown in the 40 mg L−1 treatment compared to plants in the lower level of DO treatments, except that the plant height increased with the increasing DO concentration. Root respiration increased linearly with increasing DO concentration; however, there was no effect on leaf net CO2 exchange rate. It is suggested that it was safe to enrich root zone DO to as high as 30 mg L−1, although the growth benefit was minor by increasing DO from ambient air saturated level (∼8.5 mg L−1) to 30 mg L−1. Higher than 30 mg L−1 could cause reduction in tomato plant growth. 相似文献
Persistent Escherichia coli urinary tract infection (UTI) in dogs is a frustrating clinical problem. Affected dogs often appear to fail to respond to therapy or to reacquire infection shortly after therapy is completed. Urovirulence factors (UVFs) of the infecting E. coli, antibiotic resistance, and tissue colonization may be contributory but have not been evaluated in dogs with persistent E. coli UTI. In this study, the strain types of E. coli in dogs with persistent UTI were evaluated with pulsed-field gel electrophoresis (PFGE) to determine whether persistence was due to acquisition of new isolates or failure to eradicate existing isolates. UVFs in these isolates, assessed by polymerase chain reaction, and antibiograms were correlated with treatment outcome in these dogs. Results documented a mixed pattern: 9 dogs remained chronically infected with 1 or 2 strains, each with distinct reproducible UVFs, but 1 dog was infected with numerous unrelated E. coli strains over time. Two dogs had a mixed pattern, consisting of 1 or more episodes of persistent E. coli infection attributable to a single strain in addition to episodes caused by unrelated strains. Many isolates had no detectable UVFs, highlighting the likely importance of impaired colonization resistance in the affected dogs. Antibiotic resistance was common, often in response to previous treatments, especially with trimethoprim-sulfamethoxazole. Antibiotic resistance patterns differed significantly within PFGE strain types, suggesting lateral acquisition of resistance plasmids or integrons. These results can be used to help guide testing for and management of persistent E. coli UTI in dogs. 相似文献
Field-trapping experiments with synthetic 2,7-nonadiyl dibutyrate, the female-produced sex pheromone of the orange wheat blossom midge, Sitodiplosis mosellana (Géhin), demonstrated that pheromone traps were highly attractive to males and caught very few non-target organisms. Different formulations of pheromone were tested to identify the optimum release rate and dispenser type for use in pheromone traps in the UK. Key findings were that racemic pheromone was as effective as enantiomerically pure (2S,7R)-2,7-nonadiyl dibutyrate, that release rates higher than 0.5 microg day(-1) were not necessary and that the optimal formulation was a 1 mg pheromone loading in a rubber septum. Pheromone traps gave a reliable indication of peak midge emergence, onset of flight and abundance of midges throughout the season. A strong correlation between maximum trap catch and crop infestation levels was obtained. 相似文献
We investigated 2 outbreaks of osteomalacia as a result of phosphorus (P) deficiency in herds of lactating beef cows grazing subtropical native pastures in Uruguay. Cows exhibited pica, difficulty to stand and walk, rib fractures, and body weight loss even with adequate forage availability. Osteopenia and severe osteomalacia were observed on gross and histologic examination. The concentrations of bicarbonate-extractable P in soil (4.0, 4.1 mg P/kg), total P in pasture (0.9, 1.1 g P/kg), inorganic P in serum (1.0, 0.71 mmol P/L), and P in bone (73 mg P/mL) were all low. Although injectable and mineral salt supplements provided additional P in both outbreaks, these supplementary amounts were insufficient to prevent P deficiency. The P ingested by the cows from the pasture and supplements would have provided 20–55% of their daily P requirements of ~21 g P/d. Osteomalacia occurred in cattle at the 2 ranches as a result of severe P deficiency in the soil and forage, and inadequate P supplementation. Following diagnosis, control of P deficiency in beef cattle requires estimation of the amount of pasture P ingested and provision of sufficient additional supplementary P to meet the animals’ requirements. 相似文献
OBJECTIVE: To determine effects of the selectin inhibitor TBC1269 on neutrophil-mediated pulmonary damage during acute Mannheimia haemolytica-induced pneumonia in newborn calves. ANIMALS: Eighteen 1- to 3-day-old colostrum-deprived calves. PROCEDURE: Mannheimia haemolytica or saline (0.9% NaCl) solution was inoculated in both cranial lung lobes of 12 and 6 calves, respectively. Calves were euthanatized 2 (saline, n = 3; M haemolytica, n = 4) or 6 hours (saline, n = 3; M haemolytica, n = 8) after inoculation. Four M haemolytica-inoculated calves euthanatized at 6 hours also received TBC1269 (25 mg/kg, IV) 30 minutes before and 2 hours after inoculation. Conjugated diene (CD) concentrations, inducible nitric oxide synthase (iNOS) expression, and apoptotic cell counts were determined in lung specimens collected during necropsy. RESULTS: Conjugated diene concentrations were significantly increased in all M haemolytica-inoculated groups, compared with saline-inoculated groups. Calves treated with TBC1269 had decreased concentrations of CD, compared with untreated calves, although the difference was not significant. Number of apoptotic neutrophils and macrophages increased significantly inTBC1269-treated calves, compared with untreated calves. Inducible nitric oxide synthase was expressed by epithelial cells and leukocytes. However, iNOS was less abundant in airway epithelial cells associated with inflammatory exudates. Degree of iNOS expression was similar between TBC1269-treated and untreated calves. CONCLUSIONS: Mannheimia haemolytica infection in neonatal calves resulted in pulmonary tissue damage and decreased epithelial cell iNOS expression. The selectin inhibitor TCB1269 altered, but did not completely inhibit, neutrophil-mediated pulmonary damage. 相似文献
Splenic and anterior kidney sections or whole organs were excised from large (1 kg) or small (200 g) rainbow trout (Salmo gairdneri) and placed in sterile 60 mm plastic plates containing 10 ml of Eagle's minimal essential medium (EMEM) supplemented with normal or fetal calf serum for in vitro culture. The organ samples were immunized in vitro by direct injection or by mixing in the medium Yersinia ruckeri O-antigen or dinitrophenyl-Ficoll. The medium was changed once during the 10-day incubation at 15 C. The passive hemolytic plaque assay demonstrated antibody production from the plaque-forming cells (PFC); passive hemagglutination was used to measure antibody titers in the media. High numbers of PFC occurred in cultures of either kidney or spleen, demonstrating that these organs can function independently for antibody production. Splenic sections from large fish produced more PFC than comparable whole organs from small fish. EMEM supplemented with 2% normal calf serum was a satisfactory culture medium. 2-hydroxyethyl-mercaptan an ingredient used in mammalian cell culture, inhibited antibody production in trout cells. These techniques are being used in the culture of organs and cells to elucidate pathways and sequences of antigen uptake and delivery of the immunopoietic tissues in trout. 相似文献
The incidence and clinical progression of oral lesions in a cohort of critically ill patients administered mechanical ventilation via orotracheal intubation were observed prospectively in the Intensive Care Unit (ICU) of the University of California, Davis Veterinary Medical Teaching Hospital. Oral cavities of these patients were examined within 24 hours of being placed on the ventilator and at least daily thereafter during ventilator therapy. As part of the study protocol, any lesion noted was treated. Twenty-one critically ill canine patients (median age of 7 yrs; range <1 to 19 yrs) were observed from 1 January 1995 through 31 August 1995. Over ninety percent (90.5%) of the observed patients developed oral lesions subsequent to being mechanically ventilated. Erosive and ulcerative mucosal lesions were the most frequently observed (15/43) with the tongue being the most frequently involved oral structure. Most of the observed soft tissue oral lesions appeared secondary to persistently applied pressure from teeth, mouth gags, endotracheal tubes, and other monitoring devices. Efforts taken to prevent persistently applied trauma, such as periodic positional changes of equipment and padding of susceptible structures, apeared effective in preventing oral lesions. There were indications of gastric reflux in 6 patients (28.6%), as evidenced by secretions in the oral cavity with a pH of <6 and containing digested blood. Ulcerative lesions in the subset of patients with gastric reflux seemed to worsen in severity with exposure to the low pH secretions. Over the course of the study, the ICU nursing staff developed an effective protocol for the care of the oral cavity: treating mucosal erosions and ulcers topically8 with a dilute chlorhexidine solution (0.05%), removing oral secretions via suction as needed, and padding persistently traumatized tissues with glycerin moistened gauze. Oral lesions in orotrachealy intubated and mechanically ventilated patients are predictable, preventable, and treatable. Most lesions are pressure induced, associated with monitoring/therapeutic equipment, and appear to be preventable with appropriate nursing protocls. Most observed oral lesions clinically improved with routine, periodic dilute chlorhexidine rinses and relief of applied pressure. 相似文献