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51.
The prevalence and nature of cardiac arrhythmias in horses following general anaesthesia and surgery
Ruth A Morgan Alexandra G Raftery Peter Cripps Jonathan M Senior Catherine M McGowan 《Acta veterinaria Scandinavica》2011,53(1):62
Background
The prevalence and nature of arrhythmias in horses following general anaesthesia and surgery is poorly documented. It has been proposed that horses undergoing emergency surgery for gastrointestinal disorders may be at particular risk of developing arrhythmias. Our primary objective was to determine the prevalence and nature of arrhythmias in horses following anaesthesia in a clinical setting and to establish if there was a difference in the prevalence of arrhythmias between horses with and without gastrointestinal disease undergoing surgery. Our secondary objective was to assess selected available risk factors for association with the development of arrhythmias following anaesthesia and surgery.Methods
Horses with evidence of gastrointestinal disease undergoing an exploratory laparotomy and horses with no evidence of gastrointestinal disease undergoing orthopaedic surgery between September 2009 and January 2011 were recruited prospectively. A telemetric electrocardiogram (ECG) was fitted to each horse following recovery from anaesthesia and left in place for 24 hours. Selected electrolytes were measured before, during and after surgery and data was extracted from clinical records for analysis. Recorded ECGs were analysed and the arrhythmias characterised. Multivariable logistic regression was used to identify risk factors associated with the development of arrhythmias.Results
Sixty-seven horses with gastrointestinal disease and 37 without gastrointestinal disease were recruited. Arrhythmias were very common during the post-operative period in both groups of horses. Supra-ventricular and bradyarrhythmias predominated in both groups. There were no significant differences in prevalence of any type of arrhythmias between the horses with or without gastrointestinal disease. Post-operative tachycardia and sodium derangements were associated with the development of any type of arrhythmia.Conclusions
This is the first study to report the prevalence of arrhythmias in horses during the post-operative period in a clinical setting. This study shows that arrhythmias are very common in horses following surgery. It showed no differences between those horses with or without gastrointestinal disease. Arrhythmias occurring in horses during the post-anaesthetic period require further investigation. 相似文献52.
MR Namazi 《Journal of Autoimmune Diseases》2005,2(1):11
Vitiligo is a psychologically devastating clinical conundrum which affects approximately 1% of the general population. The exact cause of the illness is an enigma, but several hypotheses about its pathogenesis are advanced.The autoimmune hypothesis proposes an autoimmune attack against melanocytes. Although anti-melanocyte autoantibodies have been demonstrated in vitiligo, recent research casts doubt on their pathogenic role and instead supports the involvement of cell-mediated autoimmune response in the pathobiology of this disorder, which is characterized by increase of suppressor T-cells and decrease of the helper/suppressor ratio in association with the presence of type-1 cytokine secreting cytotoxic T cells in the vicinity of disappearing melanocytes.The neural hypothesis proposes that increased release of norepinephrine, a melanocytotoxin, from the autonomic nerve endings in the microenvironment of melanocytes injures these cells. Moreover, norepinephrine induces the catecholamine degrading enzyme monoamine oxidase (MAO), which favors the formation of toxic levels of hydrogen peroxide in the vicinity of melanocytes.Another theory suggests that abnormal permeability of melanosome membrane, which normally prevents the diffusion of toxic melanin precursors into the cytoplasm, may cause melanocyte damage.Phenytoin, the widely-used anticonvulsant, has been employed both topically and systemically in the treatment of some dermatological disorders. The drug has been shown to significantly suppress mitogen-induced activation of lymphocytes and cytotoxic T lymphocyte activity and to polarize the immune response toward the type-2 pathway. It also significantly decreases suppressor T cells and increases the helper/suppressor ratio.At high concentrations, the drug inhibits the release of norepinephrine and the activity of MAO. Moreover, phenytoin is suggested to interact with membrane lipids, which may promote stabilization of the membranes.The hydantoin moiety of phenytoin exerts a direct stimulatory action on melanocytes; facial hyperpigmentation is a recognized side effect of orally administered phenytoin.Altogether, the above evidence suggests that phenytoin could be therapeutically effective against vitiligo. As phenytoin stimulates collagen production and inhibits its breakdown, its concomitant use with topical steroids could prevent steroid-induced skin atrophy while potentiating the anti-vitiligo effect of these agents. 相似文献
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The farrowing rates resulting from matings on different days of the week were determined for a 2800-sow intensive piggery in both 1983 and 1984. The results showed that sows mated early in the week achieved a significantly higher farrowing rate than sows mated late in the week (P less than 0.0001). During the seasonal (summer to autumn) infertility period, Wednesday matings resulted in a poor farrowing rate whereas for the rest of the year farrowing rates following Wednesday matings were similar to those for Sunday Monday and Tuesday matings. Consistent results were obtained for data from both years. It is proposed that the stress of regrouping unmated sows on Wednesday to accommodate newly weaned sows is responsible for this decrease in fertility. This study illustrates how detailed analysis of farrowing rates on a day of mating basis can identify a problem which is otherwise masked by weekly data. 相似文献
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Treatment with the synthetic glucocorticoid dexamethasone sodium phosphate increased the feed intake of sheep within 24 h. A single treatment with the longer-acting compound dexamethasone trimethylacetate had a slower effect, but resulted in improved feed intake and enhanced body weight gain over a period of 7 to 14 days. Treatment was effective in sheep housed individually and in sheep penned in groups. The improvement in body weight gain disappeared 15 to 20 days after a single treatment, but in most studies treated sheep had less variability in weight change than untreated sheep at this time. A statistically significant increase in body weight gain was observed in 8 of 11 trials; in the other 3 trials, it appeared that the feed intake of the untreated sheep was already maximal. Wethers treated with dexamethasone trimethylacetate on arrival at an assembly point for live export arrived in the Middle East 23 days later with a lower mean weight loss, partly because fewer sheep lost a significant amount of weight. 相似文献
59.
REASONS FOR PERFORMING STUDY: Despite the prevalence of orthopaedic injuries to horses, there is no objective means of quantifying the intensity of musculoskeletal pain. HYPOTHESES: Mechanical nociceptive thresholds (MNT) can be measured repeatably by pressure algometry in horses and MNTs are correlated with both severity of clinical signs and subjective scores of muscle pain on palpation in horses with suspected sacroiliac dysfunction (SID). METHODS: The technique of pressure algometry and its repeatability was tested at 4 anatomical sites on either side of the thoracolumbar and pelvic region in 12 Thoroughbreds in training. In a second series of 15 racing Thoroughbreds, using a different set of landmarks, pain on palpation was assessed by pressure algometry. Horses were grouped based on clinical scores of SID as normal (n = 5), mild (n = 5), moderate (n = 4) and severe (n = 1) suspected SID and scored for muscle pain response by manual palpation. RESULTS: Pressure algometry was shown to be a repeatable measure of MNTs. Horses with suspected SID had significantly lower mean MNT when sites and horses were pooled and showed greater differences in mean algometer measurements between left and right sides, compared to control horses. A significant correlation was found between mean pressure algometry measurements and both suspected SID grade and muscle pain response on palpation. CONCLUSION AND POTENTIAL RELEVANCE: Horses with suspected SID displayed lower MNTs compared to control horses, especially in the pelvic region. This supports a potential role for pressure algometry in providing an objective means of quantifying musculoskeletal pain reflected as a reduced MNT associated with SID and its response to physiotherapy or other treatments. 相似文献
60.
The aim of this study was to evaluate the influence of two different concentrations of plasma progesterone at the time of FSH-P treatment on the superovulatory response in dairy heifers. Sixteen reproductively sound Holstein heifers (13-15 months of age) were used in this study. Superovulatory treatment was commenced at mid-dioestrus (Day 10 ± 2 of the oestrous cycle) of the synchronized (using two injections of PGF2α, 11 days apart) oestrous cycles. Blood samples were collected on the day and the day after commencing FSH-P treatment and at oestrus for plasma progesterone determination. Heifers were grouped based on two levels of plasma progesterone; Group low progesterone (LP; ranging from 2 to 4.5 ng /ml; n = 7) and Group high progesterone (HP; ≥ 4.6 ng /ml; n = 8) at the beginning of FSH-P treatment (one heifer was excluded from the statistical analysis because of the abnormal progesterone level at oestrus). The superovulatory response in terms of mean numbers of palpable corpora lutea (ovulation rate) was significantly higher (p < 0.05) in group LP than group HP. Ovulation rate was negatively correlated (r = -0.51) with the progesterone concentration at the time of commencing FSH-P treatment (p < 0.05). Data suggest that varying concentrations of plasma progesterone at the time of FSH-P treatment may have a different effect on the outcome of superovulatory response in dairy heifers. 相似文献