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41.

Background

Computed tomography (CT) is highly accurate for diagnosing pancreatitis in humans. The diagnosis of pancreatitis in dogs is based on clinical signs, laboratory findings, and ultrasonographic (US) changes. There are, however, inherent limitations in relying on laboratory and ultrasound findings for the clinical diagnosis of pancreatitis in dogs.

Hypothesis/Objectives

We hypothesized that CT angiography would be a rapid and reliable method to confirm pancreatitis in dogs compared to ultrasonography. The aim was to describe the CT characteristics and compare them to ultrasound findings and correlate the CT appearance to the severity of the patients'' clinical course.

Animals

A prospective pilot case series; 10 dogs with pancreatitis were enrolled if the history, clinical signs, laboratory, and ultrasonographic findings were indicative of pancreatitis.

Methods

A 3‐phase angiographic CT was performed under sedation. Afterward, each dog had US‐guided aspirates of the pancreas collected and blood drawn for cPLi assay. Images were evaluated for portion of visible pancreas, pancreatic size and margin, pancreatic parenchyma, presence of peripancreatic changes and contrast enhancement pattern. The results were compared with outcome.

Results

An enlarged, homogeneously to heterogeneously attenuating and contrast‐enhancing pancreas with ill‐defined borders was identified in all dogs. CT identified more features characterizing pancreatic abnormalities compared to US. Thrombi were found in 3/10 dogs. Three dogs with heterogeneous contrast enhancement had an overall poorer outcome than those with homogenous enhancement.

Conclusions and Clinical Importance

CT angiography under sedation was used in dogs to confirm clinically suspected pancreatitis and identified clinically relevant and potentially prognostic features of pancreatitis in dogs.  相似文献   
42.
The aim of the current study was to evaluate the in vivo pharmacokinetic of ivermectin (IVM) after the administration of a long‐acting (LA) formulation to sheep and its impact on potential drug‐drug interactions. The work included the evaluation of the comparative plasma profiles of IVM administered at a single therapeutic dose (200 μg/kg) and as LA formulation at 630 μg/kg. Additionally, IVM was measured in different gastrointestinal tissues at 15 days posttreatment with both IVM formulations. The impact of the long‐lasting and enhanced IVM exposure on the disposition kinetics of abamectin (ABM) was also assessed. Plasma (IVM and ABM) and gastrointestinal (IVM) concentrations were analyzed by HPLC with fluorescent detection. In plasma, the calculated Cmax and AUC0‐t values of the IVM‐LA formulation were 1.47‐ and 3.35‐fold higher compared with IVM 1% formulation, respectively. The T1/2ab and Tmax collected after administration of the LA formulation were 2‐ and 3.5‐fold longer than those observed after administration of IVM 1% formulation, respectively. Significantly higher IVM concentrations were measured in the intestine mucosal tissues and luminal contents with the LA formulation, and in the liver, the increase was 7‐fold higher than conventional formulation. There was no drug interaction between IVM and ABM after the single administration of ABM at 15 days post‐administration of the IVM LA formulation. The characterization of the kinetic behavior of the LA formulation to sheep and its potential influence on drug‐drug interactions is a further contribution to the field.  相似文献   
43.
PARALYSIS OF CALVES BY THE TICK, IXODES HOLOCYCLUS   总被引:1,自引:0,他引:1  
  相似文献   
44.
45.
Quantitative analysis of culture using millions of digitized books   总被引:1,自引:0,他引:1  
We constructed a corpus of digitized texts containing about 4% of all books ever printed. Analysis of this corpus enables us to investigate cultural trends quantitatively. We survey the vast terrain of 'culturomics,' focusing on linguistic and cultural phenomena that were reflected in the English language between 1800 and 2000. We show how this approach can provide insights about fields as diverse as lexicography, the evolution of grammar, collective memory, the adoption of technology, the pursuit of fame, censorship, and historical epidemiology. Culturomics extends the boundaries of rigorous quantitative inquiry to a wide array of new phenomena spanning the social sciences and the humanities.  相似文献   
46.

Key message

Quercus robur seedling mass was affected more by planting density than by taproot pruning. Root pruning enhanced stem biomass at the expense of roots in later growth stages. Alteration of biomass allocation due to nursery practices may result in greater susceptibility to injury and death of the seedlings under unfavorable environmental conditions.

Context

Plants adjust their growth and modulate the resource allocation in response to applied treatments and environmental conditions.

Aims

The aim was to examine how taproot pruning in seedlings grown at different densities affected long-term growth of Quercus robur.

Methods

Seedlings, sown as acorns at two planting densities, with or without pruned roots were harvested in the second, fourth, and fifth years of growth. The effect of root pruning on biomass allocation was determined by measuring leaf, stem, and root mass fractions; carbohydrate concentrations in the roots; and C/N ratios. Specific leaf area and root length were also determined to assess morphological adaptations to growth conditions.

Results

Total seedling mass was affected more by planting density than by taproot pruning. After 4 years of growth, root mass fractions were lower and stem mass fractions were greater in seedlings planted at a higher density. Five-year old root-pruned seedlings also had a lower root mass fraction and higher stem mass fractions than unpruned seedlings. Specific root length was not affected by root pruning or planting density.

Conclusion

Decrease of relative root biomass with simultaneous increase of stem biomass may be a long-term consequence of taproot pruning of Q. robur, and the effects may manifest years after the seedling stage.
  相似文献   
47.
OBJECTIVE: To determine efficacy of vaccines incorporating QuilA, alum, dextran combined with mineral oil, or Freund adjuvant for immunization of feedlot cattle against Streptococcus bovis and Lactobacillus spp. ANIMALS: 24 steers housed under feedlot conditions. PROCEDURE: Steers were randomly assigned to 4 experimental groups and a control group. Animals in experimental groups were inoculated on days 0 and 26 with vaccines containing Freund adjuvant (FCA), QuilA, dextran combined with mineral oil (Dex), or alum as adjuvant. Serum anti-S bovis and anti-Lactobacillus IgG concentrations were measured, along with fecal pH, ruminal fluid pH, and number of S bovis and Lactobacillus spp in ruminal fluid. RESULTS: Throughout the study, serum anti-S bovis and anti-Lactobacillus IgG concentrations for animals in the Dex, QuilA, and alum groups were similar to or significantly higher than concentrations for animals in the FCA group. Serum anti-S bovis and anti-Lactobacillus IgG concentrations were significantly increased on days 26 through 75 in all 4 experimental groups, and there was a linear relationship between anti-S bovis and anti-Lactobacillus IgG concentrations. For animals in the QuilA and Dex groups, mean pH of feces throughout the period of experiment were significantly higher and numbers of S bovis and Lactobacillus spp in ruminal fluid on day 47 were significantly lower than values for control cattle. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that immunization of feedlot steers against S bovis and Lactobacillus spp with vaccines incorporating Freund adjuvant, QuilA, dextran, or alum as an adjuvant effectively induced high, long-lasting serum anti-S bovis and anti-Lactobacillus IgG concentrations. Of the adjuvants tested, dextran may be the most effective.  相似文献   
48.
A raised concentration of serum cardiac troponin I (cTnI) is a sensitive marker of cardiac myocyte injury in the cat and assays developed for its measurement in human patients have been validated in the cat. Raised levels have been associated with a number of cardiac insults including hypertrophic cardiomyopathy and trauma. Hyperthyroidism is a common disease of older cats and excess thyroid hormone is known to produce significant cardiovascular effects in this species. This study evaluated the effect of treatment for hyperthyroidism with radioactive iodine on cTnI concentration, assessed the association between thyroxin levels and glomerular filtration rate (GFR) and cTnI concentration in cats treated for hyperthyroidism and described changes in echocardiographic parameters following treatment. Prior to the treatment serum cTnI was measured and echocardiography performed, thyroxin, cTnI, and echocardiography were then repeated at various time points following radioisotope therapy. The results show that higher thyroxin levels were significantly (P=0.002) associated with a higher likelihood of the cat presenting with detectable levels of cTnI. No significant association was found between GFR and presence of detectable levels of cTnI. Furthermore the results indicate that the effects of hyperthyroidism on echocardiographic parameters appear considerably less in this study than in previous studies and that the main outcome of treatment on these parameters is a significant reduction in fractional shortening (P=0.006). These results suggest that chronic exposure to excess thyroid hormone may induce myocyte damage of sufficient severity to raise serum cTnI concentration in a proportion of cats that resolves following establishment of a euthyroid state.  相似文献   
49.
OBJECTIVE: To describe myoelectric activity of the spiral colon in healthy cows. ANIMALS: 7 lactating Simmental X Red-Holstein crossbred cows. PROCEDURE: Cows were implanted with 7 pairs of bipolar silver electrodes (4 in the spiral colon and 1 each in the cecum, distal part of the ileum, and proximal loop of the ascending colon [PLAC]). Myo-electric activity was recorded during 4 days for each cow. Patterns were analyzed, using computer-based methods. RESULTS: Myoelectric activity of the spiral colon was closely associated with motility of the ileum and PLAC and showed the typical organization of migrating myoelectric complexes (MMC). The MMC in the bovine spiral colon (bcMMC) had a mean +/- SD duration of 188.6 +/- 30.8 minutes and was divided into 4 phases. Phases I and II lasted 11.3 +/- 1.4 and 159.4 +/- 33.3 minutes, respectively. Phase III (duration, 5.4 +/- 1.2 minutes) was characterized by 5.2 +/- 0.9 regular spindles (35.4 +/- 5.4 seconds) and 1 final elongated spindle (137.2 +/- 56.4 seconds). Phase III most commonly (73.8 +/- 16.1%) was followed by phase IV (duration, 173 +/- 3.6 minutes). Propagation velocity of phase III was 4.4 +/- 0.5 cm/min, and 13.6% of bcMMC were incompletely propagated through the spiral colon. CONCLUSIONS: Myoelectric activity of the bovine spiral colon is composed of a recurring cyclic pattern similar to MMC of the small intestine. Data of colonic myoelectric activity in healthy cows will serve as a basis for studies on cecal dilatation and dislocation in cattle.  相似文献   
50.
ObjectiveThree anaesthetics (MS222, clove oil and a mixture of ketamine/diazepam) were administered to cane toads to determine their effect on the hypothalamic-pituitary-adrenal (HPA) axis. Time to induction and recovery and any adverse events were also evaluated.Study designProspective randomized experimental trial.AnimalsThirty adult male cane toads (Rhinella marina) with body mass ranging between 130 and 250 g were captured from the field.MethodsThree groups of 10 toads were anaesthetized with ketamine (200 mg kg?1) and diazepam (0.2 mg kg?1) by intramuscular injection, MS222 (3 g L?1) or clove-oil (0.3 mL L?1) both by immersion. Blood samples were collected to determine plasma corticosterone concentrations. Induction and recovery time were recorded in each treatment. After full recovery animals were euthanized and a complete post-mortem examination was performed.ResultsSignificant differences were found in the activation of the HPA axis and in the times of induction and recovery between treatments (p < 0.001). Animals anaesthetized with clove-oil had the highest levels of corticosterone in plasma (42.5 ± 21.6 ng mL?1). No differences were found between ketamine/diazepam (15.0 ± 13.3 ng mL?1) and MS222 (22.0 ± 13.6 ng mL?1) groups. The mean ± SD induction (minutes) and recovery (hours) times respectively were; ketamine/diazepam 66.5 ± 11 and 8 ± 3, clove oil 39 ± 12 and 7.6 ± 3, and MS222 42.5 ± 11 and 1.5 ± 0.5. Clove oil exposure had 30% mortality. Death followed a period of respiratory distress with changes consistent with non-cardiogenic oedema observed at post-mortem examination.Conclusions and Clinical relevanceBased on shorter induction and recovery times and minimal activation of HPA, MS222 is the anaesthetic of choice in cane toads. If it is not possible to use immersion methods of anaesthesia, ketamine/diazepam can be used but induction and recovery times are prolonged. Clove oil had unacceptable mortality in this study and should be used with extreme caution.  相似文献   
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