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31.
A study was undertaken at the Texas A&M Horse Center to evaluate and compare the effectiveness of three anthelmintics—ivermectin, fenbendazole, and a combination of ivermectin and pyrantel pamoate—on fecal egg count reductions of cyathostomes and Parascaris equorum in 30 naturally infected foals. The foals were randomized into three treatment groups, with individuals being rerandomized after each 8-week observation period. The treatments of ivermectin and fenbendazole were given at the manufacturer's recommended doses, and the pyrantel treatment was given at two times the manufacturer's recommended dose. Fecal egg counts were performed at the time of treatment and at 2-week intervals after treatment for a total of 8 weeks. Each foal received a total of three treatments during the course of the study. Fecal egg counts were performed by a modified McMaster's test, with a sensitivity of 25 eggs per gram of feces, and by the modified Wisconsin double centrifugal flotation technique, with a sensitivity of 0.2 eggs per gram of feces. Fecal egg reduction percentages were calculated. Analysis of the results showed that ivermectin, either used alone or with pyrantel, was a more effective anthelmintic for cyathostome (small strongyle) control than fenbendazole. Fenbendazole and pyrantel showed a higher initial reduction in Parascaris egg counts when compared with the ivermectin-only-treated group, but this difference lessened over time. The use of the combination treatment showed the best results for controlling both parasites, indicating that a combination of anthelmintics may be necessary to control parasites on some equine farms.  相似文献   
32.

Objective

To determine the dose of cis-atracurium needed to produce a moderate neuromuscular blockade (NMB) in pigs.

Study design

Prospective experimental study.

Animals

Seven pigs [five females and two males; median (range) body weight: 47 (36–64) kg].

Methods

Pigs were premedicated with intramuscular midazolam (0.3 mg kg?1) and ketamine (7 mg kg?1). Anaesthesia was induced with intravenous (IV) propofol 3 (1–4) mg kg?1 and maintained with isoflurane in oxygen. Based on a preliminary study, the subjects were administered 0.3 mg kg?1 cis-atracurium followed by 0.48 mg kg?1 hour?1 constant rate infusion (CRI) IV. A moderate NMB was defined as a train-of-four (TOF) count of ≤2 by acceleromyography. When the TOF count was >2, 0.1 mg kg?1 cis-atracurium was administered and the CRI was increased. The cis-atracurium CRI was decreased when the TOF count was under 2 for more than 15 minutes. The total dose of cis-atracurium required to maintain a moderate NMB was calculated as the total amount of cis-atracurium used (both CRI and supplementary boluses) divided by the administration time.

Results

The cis-atracurium CRI lasted for 87 (76–151) minutes. To induce and maintain a moderate neuromuscular blockade, the initial dose of cis-atracurium was 0.3 (0.3– 0.5) mg kg?1 and the CRI was 0.71 (0.37–0.98) mg kg?1 hour?1.

Conclusions and clinical relevance

The doses described in our study may help researchers obtain a moderate NMB using cis-atracurium in pigs.  相似文献   
33.
Wheat starch is used to make baked products for celiac patients in several European countries but is avoided in the United States because of uncertainty about the amounts of associated grain storage (gluten) proteins. People with celiac disease (CD) must avoid wheat, rye, and barley proteins and products that contain them. These proteins are capable of initiating damage to the absorptive lining of the small intestine in CD patients, apparently as a consequence of undesirable interactions with the innate and adaptive immune systems. In this study, starch surface-associated proteins were extracted from four commercial wheat starches, fractionated by high-performance liquid chromatography and gel electrophoresis, and identified by tandem mass spectrometry analysis. More than 150 proteins were identified, many of which (for example, histones, purothionins, and glutenins) had not been recognized previously as starch-associated. The commercial starches were analyzed by the R-5 enzyme-linked immunosorbent assay method to estimate the amount of harmful gluten protein present. One of these starches had a low gluten content of 7 ppm and actually fell within the range proposed as a new Codex Alimentarius Standard for naturally gluten-free foods (maximum 20 ppm). This low level of gluten indicates that the starch should be especially suitable for use by celiac patients, although wheat starches with levels up to 100 ppm are deemed safe in the proposed Codex standards.  相似文献   
34.
Chest tube drainage circuitry in mammals   总被引:2,自引:0,他引:2  
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35.
36.
p70 S6 kinase (p70S6K) is a key enzyme involved in the control of protein synthesis. We have previously shown that this kinase is insulin sensitive in chicken muscle despite a relative insulin resistance in the early steps of insulin receptor signaling in this tissue, particularly with no change in tyrosine phosphorylation of the insulin receptor substrate 1 (IRS1). The aim of the present study is to further study the p70S6K pathway in chicken muscle. By analyzing in silico several kinases involved in the protein kinase B (PKB also called AKT)/target of rapamycin (TOR)/p70S6K pathway in the chicken, we showed that the amino acid sequence of the proteins exhibited a very high identity with their homologs in mammalian species and Drosophila. We investigated the regulation of these kinases in vivo or in vitro. Refeeding and insulin treatment significantly (P<0.05) increased the phosphorylation and/or activity of kinases upstream of p70S6K such as AKT and TOR. Similarly, refeeding and insulin increased the phosphorylation of p70S6K on key residues (i.e. T389, T229 and T421/S424) and the phosphorylation of a p70S6K downstream target, the ribosomal protein S6 (by 3-10-fold, P<0.05). Interestingly, we also showed an increase in the phosphorylation level of IRS1 on S632/S635, sites involved in insulin resistance. In conclusion, the AKT/TOR/p70S6K pathway is activated by refeeding and insulin injection, which might negatively regulate IRS1 tyrosine phosphorylation. These results indicate some particularities of the insulin signaling in chicken muscle and suggest the involvement of p70S6K in these features.  相似文献   
37.
Seafoods and seaweeds represent some of the most important reservoirs of new therapeutic compounds for humans. Seaweed has been shown to have several biological activities, including anticancer activity. This review focuses on colorectal and breast cancers, which are major causes of cancer-related mortality in men and women. It also describes various compounds extracted from a range of seaweeds that have been shown to eradicate or slow the progression of cancer. Fucoidan extracted from the brown algae Fucus spp. has shown activity against both colorectal and breast cancers. Furthermore, we review the mechanisms through which these compounds can induce apoptosis in vitro and in vivo. By considering the ability of compounds present in seaweeds to act against colorectal and breast cancers, this review highlights the potential use of seaweeds as anticancer agents.  相似文献   
38.
39.
To analyze further the role in virulence of the prominent cholesterol oxidase (ChoE) of Rhodococcus equi, an allelic exchange choE mutant from strain 103+ was constructed and assessed for virulence in macrophages, in mice, and in foals. There was no difference between the mutant and parent strain in cytotoxic activity for macrophages or in intra-macrophage multiplication. No evidence of attenuation was obtained in macrophages and in mice, but there was slight attenuation apparent in four intra-bronchially infected foals compared to infection of four foals with the virulent parent strain, based on a delayed rise in temperature of the choE-mutant infected foals. However, bacterial colony counts in the lung 2 weeks after infection were not significantly different, although there was a slight but non-significant (P=0.12) difference in lung:body weight ratio of the choE mutant versus virulent parent infected foals (mean 2.67+/-0.25% compared to 4.58+/-0.96%). We conclude that the cholesterol oxidase is not important for the virulence of R. equi.  相似文献   
40.
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