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111.
Leib MS Duncan RB Ward DL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(6):1185-1192
BACKGROUND: Helicobacter pylori is a common cause of gastritis and peptic ulcers in humans. Many dogs, including those with gastritis and chronic vomiting, are infected with Helicobacter spp. HYPOTHESIS: Triple antimicrobial therapy will eradicate Helicobacter infection, improve gastritis, and reduce clinical signs. The addition of acid suppression medication will not improve results. ANIMALS: Twenty-four pet dogs with chronic vomiting and gastric Helicobacter spp. METHODS: Dogs were randomly assigned to triple antimicrobial therapy with or without famotidine. Gastroduodenoscopy was performed 4 weeks and 6 months after therapy. Helicobacter spp status was determined by histologic assessment of gastric mucosal biopsy specimens. RESULTS: Eradication rates for each treatment were not significantly different and combined were 75 and 42.9% at 4 weeks and 6 months, respectively. A greater improvement in gastritis scores occurred in dogs that became Helicobacter spp negative. Overall, the frequency of vomiting was reduced by 86.4%, but there were no differences between treatments. CONCLUSIONS AND CLINICAL IMPORTANCE: Eradication rates of Helicobacter spp with both treatments were not significantly different. Eradication rates at 6 months were modest, and more effective treatments should be developed. Acid suppression is not a necessary component of treatment protocols for dogs. Eradication of gastric Helicobacter spp was associated with improvement in gastritis scores. Dramatic reduction of the vomiting frequency occurred with both treatment protocols. Gastric Helicobacter spp may cause or contribute to chronic vomiting and gastritis in some dogs. 相似文献
112.
Sara J. Bruce BVMS W.G. GUILFORD BVSc PhD Duncan I. Hedderley Miho Mccauley 《Veterinary radiology & ultrasound》1999,40(5):472-476
Ten healthy dogs were fed 30 1.5 mm and 10 5 mm radiopaque markers (BIPS, MedID, Grand Rapids) mixed with sufficient quantities of a high fibre diet to meet 25% of their estimated daily caloric requirements. Abdominal radiographs were made at two hour intervals until 90% of the small and large markers had left the colon. The mean residence times (MRT) of each size of marker in the proximal, distal and total colon were calculated using kinetic analysis. The MRT's of the small markers were 4.9 hours (SD 4.4), 7.1 hours (SD 3.3) and 12.0 hours (SD 7.1) respectively. The MRT's of the large markers were not significantly different from the small markers except in the proximal colon where they were significantly shorter (3.2 hours, SD 2.3). Reference colonic filling and colonic transit curves for both sizes of markers were constructed. These may be useful to detect abnormal colonic transit in dogs. 相似文献
113.
Summary A method used for estimating extractable maleic hydrazide (MH) concentrations in fresh potato material, concentration range
5–17 mg kg−1, was found not to be suitable for processed potato products (10–33% recoveries) although, boiling potato pieces enhanced
recovery by 20%. Each step of the determination was examined and a modified procedure developed with particular emphasis on
the extraction of MH from the dried potato matrix, and the quality of the HPLC column used. Potato slices and model systems
based on filter papers plus additives were used. Recoveries from fried potato slices were 74±6%. Based on the effect of glucose
in reducing extractable MH recoveries, it is suggested that the remainder of the MH (20–25%) is converted into a conjugated
structure on reaction with dehydrated sugar (Diels-Alder reaction). 相似文献
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Yield and nitrogen use efficiency of wheat increased with root length and biomass due to nitrogen,phosphorus, and potassium interactions 下载免费PDF全文
Elliott G. Duncan Cathryn A. O'Sullivan Margaret M. Roper Jairo Palta Kelley Whisson Mark B. Peoples 《植物养料与土壤学杂志》2018,181(3):364-373
Balanced applications of nitrogen (N), phosphorus (P), and potassium (K) are known to increase grain yield of wheat but the impact of the interactions among N, P, and K on root growth and nitrogen use efficiency (NUE) have not been proven. The aim of this study was to investigate the effect of balanced applications of N, P, and K on the rooting patterns and NUE of wheat. Two glasshouse experiments were conducted. A rhizobox study was used to assess the impact of interactions among N, P, and K fertilisers on total root length, biomass, specific root length, root length density, N use efficiency (NUE), and N uptake efficiency of the shoots (NUpEshoot) and N nutrition index. In a separate pot study, plants were grown to maturity to confirm the effect of the observed changes in root growth on NUE, NUpEgrain, and grain/biomass yield. In the rhizobox experiment when plants were supplied with N+P+K, total root biomass increased approximately six‐fold relative to plants grown with N alone or with no fertiliser. Plants exposed to N+P+K had NUpEshoot and NUE values that were five and ten times higher, respectively, than plants that received just fertiliser N. Plants supplied with N+P or N+P+K had N nutrition indices close to one (N‐adequate), while plants that only received N had an index of 0.62 (N‐deficient). The pot study confirmed that the changes in root length and biomass in plants exposed to N+P+K resulted in significant increases in NUE, NUpEgrain, shoot biomass, and grain yield at maturity. Interactions among fertiliser N, P, and K played a critical role in influencing root biomass and length, which was associated with increases in NUE, NUpEshoot and NUpEgrain. 相似文献
116.
With their widespread utilization, cut-to-length harvesters have become a major source of ‘‘big data' for forest management as they constantly capture, and provide a daily flow of, information on log production and assortment over large operational areas. Harvester data afford the calculation of the total log length between the stump and the last cut but not the total height of trees. They also contain the length and end diameters of individual logs but not always the diameter at breast height overbark(DBHOB) of harvested stems largely because of time lapse, operating and processing issues and other system deficiencies. Even when DBHOB is extracted from harvester data, errors and/or bias of the machine measurements due to the variation in the stump height of harvested stems from that specified for the harvester head prior to harvesting and diameter measurement errors may need to be corrected. This study developed(1) a system of equations for estimating DBHOB of trees from diameter overbark(DOB) measured by a harvester head at any height up to 3 m above ground level and(2) an equation to predict the total height of harvested stems in P. radiata plantations from harvester data. To generate the data required for this purpose, cut-to-length simulations of more than 3000 trees with detailed taper measurements were carried out in the computer using the cutting patterns extracted from the harvester data and stump height survey data from clearfall operations. The equation predicted total tree height from DBHOB, total log length and the small end diameter of the top log. Prediction accuracy for total tree height was evaluated both globally over the entire data space and locally within partitioned subspaces through benchmarking statistics. These statistics were better than that of the conventional height-diameter equations for P. radiata found in the literature, even when they incorporated stand age and the average height and diameter of dominant trees in the stand as predictors. So this equation when used with harvester data would outperform the conventional equations in tree height prediction. Tree and stand reconstructions of the harvested forest is the necessary first step to provide the essential link of harvester data to conventional inventory, remote sensing imagery and Li DAR data. The equations developed in this study will provide such a linkage for the most effective combined use of harvester data in predicting the attributes of individual trees, stands and forests, and product recovery for the management and planning of P. radiata plantations in New South Wales, Australia. 相似文献
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The subcutaneous (SC) route is often chosen for drug administration in cats because it is easier to perform than intravenous (IV) injection and is perceived as less painful than intramuscular (IM) injection. However, little is known of how the route of administration influences the pharmacodynamics of drugs. This study measured the changes in skin temperature and thermal threshold (TT) and recorded the side-effects after SC injection of 0.1mg/kg of hydromorphone in six cats. Time to peak TT was 105min. Skin temperature was elevated at 15min and between 45 and 360min. Five cats vomited and two exhibited marked dysphoria. Compared to previously published studies of IV and IM administration of hydromorphone, the SC route results in a slower onset of peak effect, a shorter duration of antinociception and is associated with more undesirable side-effects. As with IV and IM injections, SC administration of hydromorphone at 0.1mg/kg is associated with a significant elevation in skin temperature. Overall, the SC route appears to have the least utility. 相似文献
120.