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81.
Diagnosis of feline hypertrophic cardiomyopathy currently is based on the presence of myocardial hypertrophy detected using conventional echocardiography. The accuracy of tissue Doppler imaging (TDI) for earlier detection of the disease has never been described. The objective of this sudy was to quantify left ventricular free wall (LVFW) velocities in cats with hypertrophic muscular dystrophy (HFMD) during preclinical cardiomyopathy using TDI. The study animals included 22 healthy controls and 7 cats belonging to a family of cats with HFMD (2 affected adult males, 2 heterozygous adult females, one 2.5-month-old affected male kitten, and 2 phenotypically normal female kittens from the same litter). All cats were examined via conventional echocardiography and 2-dimensional color TDI. No LVFW hypertrophy was detected in the 2 carriers or in the affected kitten when using conventional echocardiography and histologic examination, respectively. The LVFW also was normal for 1 affected male and at the upper limit of normal for the 2nd male. Conversely, LVFW dysfunction was detected in all affected and carrier cats with HFMD when using TDI. TDI consistently detects LVFW dysfunction in cats with HFMD despite the absence of myocardial hypertrophy. Therefore, TDI appears more sensitive than conventional echocardiography in detecting regional myocardial abnormalities.  相似文献   
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OBJECTIVE: In light of the emerging obesity pandemic, front-of-pack calories labels may be an important tool to assist consumers in making informed healthier food choices. However, there is little prior research to guide key decisions on whether caloric content should be expressed in absolute terms or relative to recommended daily intake, whether it should be expressed in per serving or per 100 g and whether the information should be further brought alive for consumers in terms of what the extra calorie intake implies in relation to activity levels. The present study aimed at providing more insight into consumers' appreciation of front-of-pack labelling of caloric content of food products and their specific preferences for alternative execution formats for such information in Europe. DESIGN: For this purpose, eight executions of front-of-pack calorie flags were designed and their appeal and information value were extensively discussed with consumers through qualitative research in four different countries (Germany, The Netherlands, France and the UK). RESULTS: The results show that calories are well-understood and that participants were generally positive about front-of-pack flags, particularly when flags are uniform across products. The most liked flags are the simpler flags depicting only the number of calories per serving or per 100 g, while more complex flags including references to daily needs or exercise and the flag including a phrase referring to balanced lifestyle were least preferred. Some relevant differences between countries were observed. Although participants seem to be familiar with the notion of calories, they do not seem to fully understand how to apply them. CONCLUSION: From the results, managerial implications for the design and implementation of front-of-pack calorie labelling as well as important directions for future research are discussed.  相似文献   
84.
[目的]探讨麦田间作对麦长管蚜种群的生态调控作用。[方法]田间调查小麦单作田、小麦与绿豆、小麦与豌豆以8:2行距间作田麦长管蚜种群数量及其时间动态变化;室内利用"Y"型嗅觉仪测定麦长管蚜对小麦、小麦与绿豆、小麦与豌豆不同组合气味的选择性。[结果]麦田间作不能影响麦蚜种群随时间动态变化曲线,但能在一定程度上降低麦长管蚜无翅蚜和有翅蚜的数量。室内麦长管蚜无翅蚜和有翅蚜显著选择寄主植物的气味。当小麦与绿豆或小麦与豌豆组合时对麦长管蚜没有吸引作用。[结论]非寄主植物的气味对寄主植物气味起掩盖作用,干扰蚜虫的寄主定位,这可能是间作低于单作蚜量的原因之一。  相似文献   
85.
Juvenile rainbow trout were fed a plant‐based diet supplemented with inorganic Mn added at 0, 0.5, 1, 2, 4, 8, 16, or 32 mg/kg diet for 12 wk. Whole‐body Mn concentrations increased with increasing dietary levels. Rainbow trout fed 2–8 mg Mn/kg diet exhibited weight gain that was significantly higher than fish fed 0, 0.5, 1, 16, and 32 mg Mn/kg diet. Feed conversion ratio (FCR) showed a similar trend, where FCR values decreased with increasing dietary Mn until concentrations reached 8 mg Mn/kg, after which they increased. A rational nonlinear model (R2 = 0.84) fit to weight‐gain data showed that the optimal predicted supplementation level for Mn was 4.8 mg/kg diet. The optimal predicted supplementation level for Mn was similar for FCR (5 mg Mn/kg diet). The predicted 5 mg/kg diet of supplemental Mn required for the plant‐based diet formulation examined in this study is lower than the National Research Council–recommended supplementation level of 12 mg/kg. However, due to potential differences in bioavailability or retention of Mn among plant‐protein sources, the level of dietary supplementation for optimal growth could be slightly higher or lower depending on the dietary formulation.  相似文献   
86.
Ticks are known vectors for a wide range of pathogenic microorganisms. Their role in the transmission of some others is so far only suspected. Ticks can transmit multiple pathogens, however, little is known about the co-existence of these pathogens within questing ticks. We looked for the presence of DNA from three micro-organisms, Bartonella sp., Borrelia burgdorferi sensu lato and Babesia sp. which are known or suspected tick-borne pathogens, using a cohort of 92 questing Ixodes ricinus ticks collected from pastures in northern France. DNA was extracted from each individual tick and the presence of the three pathogens was investigated using Polymerase Chain Reaction (PCR) amplification. Nine among 92 samples (9.8%) demonstrated PCR products using Bartonella specific primers, 3 among 92 (3.3%) using Borrelia burgdorferi sensu lato specific primers and 19 among 92 (20.6%) using Babesia specific primers. Seven among 92 samples (7.6%) were PCR positive for at least two of the pathogens and one sample was positive for all three. Adult ticks (12/18; 67%) showed significantly higher infection rates compared to nymphs (11/74; 15%) for all three pathogens (P < 0.001). This study is the demonstration of the simultaneous presence of Bartonella sp., Borrelia burgdorferi sensu lato and Babesia sp. in questing Ixodes ricinus ticks.  相似文献   
87.
A rat, given a single oral dose of [14C] cymoxanil, 1-(2-cyano-2-methoxyimino-[2-14C]-acetyl)-3-ethylurea, eliminated 91% of the radioactivity within 72 h. The urine contained 71%, the faeces 11%, and the expired air about 7% of the radiolabel; no 14C residue was found in the internal organs. Greater than 70% of the radioactivity in the urine was identified. The major metabolite was characterised as glycine, both free and conjugated, as hippuric acid and phenylaceturic acid [N-(phenylacetyl)-glycine], and probably in the form of polypeptides of low molecular weight. The other metabolites identified included 2-cyano-2-methoxyiminoacetic acid, 2-cyano-2-hydroxyiminoacetic acid and 1-ethylimidazolidine-2, 4, 5-trione. The minor metabolites included succinic acid and 2-oxoglutaric acid which indicated reincorporation of metabolic 14C. Cymoxanil, as such, was not detected in the urine.  相似文献   
88.
The objectives of this study were to determine the prevalence and characteristics of Clostridium difficile shedding in owned dogs in Nigeria and Malawi. Clostridium difficile was isolated from 31/120 (26%) dogs in Nigeria and 11/92 (12%) dogs in Malawi (p = 0.012). Overall, 22/42 (52%) isolates were toxigenic; 17/31 (55%) from Nigeria and 5/11 (45%) from Malawi. All toxigenic isolates possessing tcdA and tcdB, and only one also possessed cdtA/B. Sixteen different ribotypes were found, ten (63%) of which were non‐toxigenic. Most isolates corresponded to ribotypes that have been previously identified in humans or livestock. The role of dogs in transmission of C. difficile and the clinical implications of C. difficile shedding in dogs remain unclear. These data indicate that dogs could act as a source of C. difficile for exposure of other species, including humans; however, the true risk is unknown. Further study of the ecology of C. difficile and the role of dogs in disease of humans and other domestic animals is indicated.  相似文献   
89.

Objective

1) To determine the pharmacokinetics of tramadol hydrochloride and its active metabolite, O-desmethyltramadol (M1), after administration through different routes in female and male C57Bl/6 mice; 2) to evaluate the stability of tramadol solutions; and 3) to identify a suitable dose regimen for prospective clinical analgesia in B6 mice.

Study design

Prospective, randomized, blinded, parallel design.

Animals

A total of 18 male and 18 female C57Bl/6 mice (20–30 g).

Methods

Mice were administered 25 mg kg?1 tramadol as a bolus [intravenously (IV), intraperitoneally (IP), subcutaneously (SQ), orally per gavage (OSgavage)] over 25 hours [orally in drinking water (OSwater) or Syrspend SF (OSSyrsp)]. Venous blood was sampled at six predetermined time points over 4 to 31 hours, depending on administration route, to determine tramadol and M1 plasma concentrations (liquid chromatography and tandem mass spectrometry detection). Pharmacokinetic parameters were described using a noncompartmental model. The stability of tramadol in water (acidified and untreated) and Syrspend SF (0.20 mg mL?1) at ambient conditions for 1 week was evaluated.

Results

After all administration routes, Cmax was >100 ng mL?1 for tramadol and >40 ng mL?1 for M1 (reported analgesic ranges in man) followed by short half-lives (2–6 hours). The mean tramadol plasma concentration after self-administration remained >100 ng mL?1 throughout consumption time. M1 was found in the OSSyrs group only at 7 hours, whereas it was detectable in OSwater throughout administration. Tramadol had low oral bioavailability (26%). Short-lasting side effects were observed only after IV administration. Water and Syrspend SF solutions were stable for 1 week.

Conclusions and clinical relevance

1) At the dose administered, high plasma concentrations of tramadol and M1 were obtained, with half-life depending on the administration route. 2) Plasma levels were stable over self-consumption time. 3) Solutions were stable for 1 week at ambient conditions.  相似文献   
90.
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