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171.
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Reasons for performing study: Studies investigating the clinical efficacy of albuterol administered with the same propellant and commercially available delivery devices in horses with recurrent airway obstruction (RAO) are not currently available. Objectives: To determine the efficacy of aerosolised albuterol administered to horses with RAO by means of 2 commercially available, hand‐held delivery devices. Methods: Ten horses with RAO were kept in a dusty environment and fed mouldy hay to induce airway obstruction. Lung mechanics were measured before and after the procedure. ΔPmax was measured 5 min after administration of 180 µg of albuterol from a pressurised metered dose inhaler, using an aerosol delivery device chosen randomly. This process was repeated every 5 min until maximal bronchodilation was achieved. After a 24 h washout period, lung mechanics data were again collected using the other aerosol delivery device. Results: Aerosolised albuterol induced a significant and rapid bronchodilation in the horses using both aerosol delivery devices. No statistically significant difference in pulmonary function was observed in response to albuterol therapy between the 2 devices. The dose required to achieve 50% of maximal bronchodilation was not statistically different between the 2 devices (173.35 ± 78.35 µg with Device 1 and 228.49 ± 144.99 µg with Device 2, P = 0.26). The decrease in lung resistance tended to be more pronounced after albuterol administration with Device 1 (P = 0.066). Conclusions: Aerosolised albuterol is an effective bronchodilator in horses with recurrent airway obstruction. There is no statistically significant difference between the 2 commercially available aerosol delivery devices in terms of efficacy. Potential relevance: Aerosolised albuterol is effectively delivered using currently available devices leading to maximal bronchodilation in horses with RAO at an average dose of 540 µg.  相似文献   
174.
Eight Holstein bull calves were divided into two groups; a non-treated control group and a famotidine treated group. Fresh milk was fed twice a day. The experiment was conducted between 7 and 14 days of age. During the experimental period the control group was injected with physiological saline, and the famotidine group was injected with famotidine, a histamine-H2-receptor blocker, into the jugular vein 30 minutes prior to each feeding. The control group showed maximum curd formation 2 h after feeding at both 7 and 14 days of age. Curd scores of 7-day-old and 14-day-old calves were significantly lower in the famotidine than in the control group at 2 and 4 h after feeding. Most fecal samples from the famotidine group exhibited an acidic smell. The famotidine group showed significantly lower values for both average weight gain and the rate of weight gain from 7 to 14 days of age. The inhibition of gastric acid secretion decreased curd formation in the abomasum as well as daily weight gain compared to non-treated control calves. This suggested that curd formation in the abomasum is important for the weight gain of newborn calves.  相似文献   
175.
U 形渠道量水平板水力性能试验研究   总被引:1,自引:0,他引:1  
根据北方灌区渠道底坡缓且灌溉水流多泥沙的现状,该文针对U型渠道设计了平板量水装置。为了探索不同尺寸悬垂薄平板在明渠水流冲击作用下的水力学特性,确定流量与平板偏转角度之间的关系。分析水流流态,将渠道运动水流分为3部分,对平板部分水流应用闸孔淹没出流公式,建立流量计算模型,得出流量与角度的半经验关系式。对流量系数计算模型中的待定系数进行估计,得到了统一形式的流量公式。U型平板测流范围为9~44L/s,经验证,计算流量与实测流量之间最大相对误差为6.9%,平均相对误差为3.2%,其中收缩比0.547、0.439平板测流相对误差均小于5%,满足灌区量水要求。同一收缩比板型,相对水头损失随着流量增大而减小,不同收缩比板型,相对水头损失随着板型收缩比增大而增大,除收缩比0.715平板在小流量(本试验大约为10L/s)测流时,相对水头损失比在10%以上,其余平板测流时相对水头损失均小于10%,其中收缩比为0.439和0.337平板最大水头损失不超过上游总水头6%。经过综合分析,选择0.547到0.439为平板最佳收缩比测流范围。研究可为灌区量水设施的改进提供依据。  相似文献   
176.
AIMS: To retrospectively evaluate the medical and surgical records of horses with acute small intestinal obstructions associated with Parascaris equorum infection; to describe the gastrointestinal lesions; and to determine the outcome of cases with such lesions.

METHODS: Records of 25 horses with acute small intestinal obstruction associated with P. equorum between 1985 and 2004 were reviewed to determine signalment, history, physical examination, surgical or post-mortem findings, and outcome.

RESULTS: All horses except one were less than 12 months old. Standardbreds were over-represented in the population studied. Sixteen horses (72%) had been administered anthelmintics, including pyrantel (n=8), ivermectin (n=7), and trichlorphon (n=1), within 24 h prior to the onset of colic. Of the 25 cases reviewed, 16 had simple obstructive ascarid impactions (SOAIs), and nine had complicated obstructive ascarid impaction (COAI) including volvulus (n=6) or intussusception (n=3), both concurrent with ascarid impaction of the small intestine. Short-term survival (discharge from hospital) occurred in 79% of horses treated for SOAI, and was 64% for all horses. Long-term survival (>1 year) occurred in 33% of horses with SOAI, and the overall long-term survival was 27% for all horses. Formation of adhesions was the most frequent finding associated with death for horses that did not survive long-term.

CONCLUSIONS AND CLINICAL RELEVANCE: The incidence of anthelmintic treatment within 24 h of the onset of colic in this study population (72%) was higher than that previously reported. Resistance of P. equorum to ivermectin recently reported in Ontario may be associated with increased ascarid burdens, predisposing horses to ascarid impaction. The long-term survival of these horses was better than that reported previously.  相似文献   
177.
目的 观察加减藿朴夏苓汤配合胃动力仪治疗功能性消化不良脾胃湿热证患者的临床疗效及安全性。方法 将71例功能性消化不良脾胃湿热证患者按照随机数字表法分为综合治疗组(简称综合组)31例、中药治疗组(简称中药组)及西药治疗组(简称西药组)各20例。综合组予加减藿朴夏苓汤口服,配合胃动力治疗仪治疗;中药组予加减藿朴夏苓汤口服;西药组予盐酸伊托必利片、泮托拉唑钠肠溶胶囊口服,3组疗程均为2周。治疗结束后对疾病疗效、中医证候积分变化、VAS评分及不良反应进行统计分析。结果 综合组总有效率为96.8%,优于中药组的80.0%及西药组的75.0%(P<0.05)。3组治疗后中医证候总积分及上腹疼痛VAS评分较治疗前均明显降低(P<0.05),且综合组降低更为显著(P<0.05)。综合组及中药组未出现明显的不良反应。结论 加减藿朴夏苓汤配合胃动力仪治疗功能性消化不良脾胃湿热证患者疗效优于单纯中药或西药治疗,能有效缓解临床症状,安全无副作用,值得临床推广。  相似文献   
178.
A 9-year-old female spayed mixed-breed dog was presented with a ten-week history of vomiting. A survey abdominal radiograph showed a soft tissue mass on the lesser curvature of the stomach and an adjacent thickened greater curvature. A barium contrast study confirmed the presence of this mass. The radiographic diagnosis was gastric tumor. Radiographic signs of gastric neoplasia include soft tissue masses or thickening of the stomach wall, delayed gastric emptying, immobility of portions of the stomach wall, and residual stomach-wall staining by barium. Necropsy revealed a gastric lymphosarcoma that had infiltrated the entire circumference of the pyloric antrum. The most common gastric malignancy in the dog is adenocarcinoma. Gastric lymphosarcoma is considered rare.  相似文献   
179.
Dynamic nasopharyngeal collapse with upper airway obstruction is an important cause of exercise intolerance in performance horses. Its underlying pathophysiology is not fully understood. We hypothesize that head position affects pharyngeal diameter, and thus head position may be a contributing factor to nasopharyngeal obstruction. Fifteen adult healthy horses were subjected to endoscopy and radiography at rest. The pharyngeal diameter was measured at nine different head and neck positions. The effect of sedation and breathing cycle on the pharyngeal diameter was determined, and the relationship between the head angle and the pharyngeal diameter was analyzed. There was a significant influence of head and neck position on pharyngeal diameter, with head position having the major effect (P<0.001); neck position was less important, but still significant (P<0.05). The smallest pharyngeal diameter was found at the dorsal, flexed position, which is a clinically important head position in dressage horses. The largest pharyngeal diameter was found at the extended midway position. At each head level, the pharyngeal diameter decreased with flexing the head and it increased with extending the head. The head angle was not associated with pharyngeal diameter, and neither sedation status nor breathing cycle significantly affected pharyngeal diameter. A decrease in pharyngeal diameter will limit the airflow through the upper respiratory tract, and it may result in turbulence with subsequent dynamic collapse. Head and neck position should therefore be considered a possible contributing factor in horses with suspected nasopharyngeal dysfunction.  相似文献   
180.
To contribute to early diagnosis and treatment of gastric ulcer of foals, we examined the gastric mucosa of healthy and affected foals using an endoscope. In healthy foals, the characteristic changes in the development of the squamous mucosa were seen mainly in the squamous mucosa, and maturation of the squamous mucosa in the greater curvature (GC-S) occurred more slowly than that of the squamous mucosa in the lesser curvature (LC-S). Epithelial desquamation in the LC-S and GC-S was observed between 6 and 90 days but was not observed in the LC-S at about 60 days, whereas it was observed in the GC-S until 90 days old. These findings suggest that there is a difference in the development of the gastric mucosa by region and that desquamation continues over a term longer than studies have reported in the past. In the affected foals, the minimum age at which gastric ulcer was observed was 4 days old. Gastric ulcers formed predominantly in the squamous mucosa (LC-S and GC-S) of foals with an immature mucosa before the weaning period, and the peak incidence occurred between 61 and 90 days old. The differences in the ulceration sites were considered to depend on the difference in the development (maturation) stage of the squamous mucosa. The grading score of the gastric ulcer increased with the growth of the affected foals. The gastric ulcer might be enhanced greatly by stress in the weaning period.  相似文献   
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