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我国奶牛养殖规模不断扩大,奶业产值比重逐步提高,给奶牛疫病防治带来巨大压力。奶牛乳房炎及细菌性肺炎等呼吸系统疾病和细菌性肠炎等消化系统疾病最为常见,抗菌药物的使用成为主要防治手段。但抗菌药物的不当使用易使细菌产生耐药性,增加临床治疗的成本和难度,危害我国奶牛产业发展。本文对截至2021年7月我国和美国、英国、日本、欧盟批准用于奶牛的抗菌药物产品进行整理、统计与分析,包括抗菌药物的分类、剂型以及适应证等,旨在为我国奶牛用抗菌药物管理、合理用药和新兽药开发提供参考。 相似文献
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Jayaraman Chandrasekaran Embry Kyle R. Mummidisetty Chaithanya K. Moon Yaejin Giffhorn Matt Prokup Sara Lim Bokman Lee Jusuk Lee Younbaek Lee Minhyung Jayaraman Arun 《Journal of neuroengineering and rehabilitation》2022,19(1):1-13
Numerous studies showed that postural balance improves through light touch on a stable surface highlighting the importance of haptic information, seemingly downplaying the mechanical contributions of the support. The present study examined the mechanical effects of canes for assisting balance in healthy individuals challenged by standing on a beam. Sixteen participants supported themselves with two canes, one in each hand, and applied minimal, preferred, or maximum force onto the canes. They positioned the canes in the frontal plane or in a tripod configuration. Statistical analysis used a linear mixed model to evaluate the effects on the center of pressure and the center of mass. The canes significantly reduced the variability of the center of pressure and the center of mass to the same level as when standing on the ground. Increasing the exerted force beyond the preferred level yielded no further benefits, although in the preferred force condition, participants exploited the altered mechanics by resting their arms on the canes. The tripod configuration allowed for larger variability of the center of pressure in the task-irrelevant anterior–posterior dimension. High forces had a destabilizing effect on the canes: the displacement of the hand on the cane handle increased with the force. Given this static instability, these results show that using canes can provide not only mechanical benefits but also challenges. From a control perspective, effort can be reduced by resting the arms on the canes and by channeling noise in the task-irrelevant dimensions. However, larger forces exerted onto the canes can also have destabilizing effects and the instability of the canes needs to be counteracted, possibly by arm and shoulder stiffness. Insights into the variety of mechanical effects is important for the design of canes and the instructions of how to use them. 相似文献
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Rhee Tae-Min Kim Hyung-Kwan Choi You-Jung Lee Hyun-Jung Hwang In-Chang Yoon Yeonyee E. Kim Hack-Lyoung Park Jun-Bean Lee Seung-Pyo Kim Yong-Jin Cho Goo-Yeong 《The international journal of cardiovascular imaging》2022,38(9):1939-1950
The International Journal of Cardiovascular Imaging - The new version of EchoPAC platform was recently developed by General Electronics (GE) to provide ‘vendor-independent’... 相似文献
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Lee Jeesoo El Hangouche Nadia Pathrose Ashitha Soulat Gilles Barker Alex J. Thomas James D. Markl Michael 《The international journal of cardiovascular imaging》2022,38(9):2047-2056
The International Journal of Cardiovascular Imaging - This study investigated the impact of bicuspid aortic valve (BAV) on valve morphology and motion as well as proximal and aortic hemodynamics... 相似文献
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目的 研究内镜超声检查术(endoscopic ultrasound,EUS)判断早期胃癌浸润深度的准确性及影响因素。方法 回顾性分析2014年1月—2020年8月于北京友谊医院就诊、行EUS且EUS分期为T1的早期胃癌患者的资料。比较EUS与术后病理浸润深度的一致性,计算EUS判断早期胃癌浸润深度的准确率、灵敏度及特异度,并探究影响EUS准确性的相关因素。单因素及多因素分析均采用Logistic回归模型。结果 共纳入380处病变,EUS发现黏膜内(T1a)病变301处,黏膜下层(T1b)病变79处;术后病理实际浸润深度为T1a病变320处,T1b病变60处。EUS判断早期胃癌浸润深度的准确率为77.1%(293/380),灵敏度为83.4%(267/320),特异度为43.3%(26/60)。多因素分析提示,病变位于胃上1/3部(OR=2.272,95%CI:1.266~4.080,P=0.006)、病变长径≥20 mm(OR=2.013,95%CI:1.200~3.377,P=0.008)及低分化癌(OR=2.090,95%CI:1.018~4.294,P=0.045)是影响EUS分期准确性的独立危险因素。低分化癌(OR=4.046,95%CI:1.737~9.425,P=0.001)是EUS过度分期的危险因素。结论 EUS对于早期胃癌浸润深度的判断具有一定的临床应用价值,影响EUS分期准确性的因素包括病变位于胃上1/3部、病变长径≥20 mm及低分化癌,其中低分化癌是EUS过度分期的危险因素。 相似文献
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目的比较飞秒激光制瓣准分子激光原位角膜磨镶术(FS-LASIK)、全飞秒激光小切口角膜基质透镜取出术(SMILE)和有晶状体眼后房型人工晶状体(ICL V4c)植入术三者矫正中低度近视的效果。方法采用回顾性研究。以惠州爱尔眼科医院2019年6月至2020年4月矫正中低度近视120例(120眼)作为研究对象,受术者分为FS-LASIK组、SMILE组及ICL组,每组40例(40眼),各组分别接受相应的手术,术后随访3个月比较其矫正效果。结果术后1个月及3个月,3组间视力及有效性指数对比差异无统计学意义(P>0.05);ICL组安全性指数高于SMILE组及FS-LASIK组(P<0.05)。术后3个月FS-LASIK组的三叶草像差、彗差和球差出现明显变化,而SMILE组的变化较小,ICL组变化最小(P<0.05)。结论对中低度近视FS-LASK、SMILE及ICL植入术三者均有确切疗效,而ICL V4c植入术的安全性最高,患者的视觉质量最好。 相似文献
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Prevalence of cataract and cataract surgery in urban and rural Chinese populations over 50 years old:a systematic review and Meta-analysis 下载免费PDF全文
Yi-Fan Du Han-Ruo Liu Yue Zhang Wei-Ling Bai Ru-Yue Li Run-Zhou Sun Ning-Li Wang 《国际眼科》2022,15(1):141-149
AIM:To summarize the data of epidemiological studies on cataract prevalence over 50 years old in urban and rural areas of China from 2000 to 2020,and to analyze the prevalence of cataract and operation rate in China.METHODS:By searching Pub Med,EMBASE,Web of Science,Wanfang Data and CNKI,Chinese and English literatures on the prevalence of cataract in China were retrieved,and the relevant characteristic data were extracted.Then,Stata v15 SE software was used for Metaanalysis and heterogeneity test.According to the results of heterogeneity,the corresponding effect models were selected to combine the extracted data.RESULTS:A total of 20 studies were included in this study,with a total of 111434 cases.Meta-analysis showed heterogeneity.According to the random effect model,the overall prevalence of cataract in Chinese people over 50 years old was 27.45%,that in rural was 28.79%,and that in urban was 26.66%.The overall coverage rate of cataract surgery was 9.19%.CONCLUSION:The prevalence of cataract is high in China,and there is still room for improvement in surgical coverage,so it is very important to promote cataract screening and prevention. 相似文献
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