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81.
K. M. McLay J. P. Nederveen J. J. Koval D. H. Paterson J. M. Murias 《Clinical physiology and functional imaging》2018,38(4):663-669
Flow‐mediated dilation (FMD) is calculated as the greatest percent change in arterial diameter following an ischaemic challenge. This Traditional %FMD calculation is thought to have statistical bias towards baseline diameter (Dbase), which is reduced by allometric scaling. This study examined whether allometric scaling FMD influenced the difference between a group of healthy young and older adults compared to the Traditional %FMD, and to determine whether a New (allometric) scaling %FMD improved the ability to obtain individually scaled FMD. Popliteal artery FMD was assessed in 18 young (26 ± 3 years) and 17 older adults (77 ± 5 years). ‘Corrected’ mean FMD was generated from a log‐linked ANCOVA model. Individual %FMD was evaluated using three calculations: (1) Traditional %FMD calculation; (2) Atkinson (allometric) scaling %FMD (peak diameter ); and (3) New scaling %FMD . Traditional %FMD was significantly larger in young (5·82 ± 2·58%) versus old (3·72 ± 1·26%). ‘Corrected’ FMD means (Y: 5·97 ± 2·12%; O: 3·98 ± 2·06%) were similar to Traditional %FMD; however, the logarithmic transformation prevents statistical interpretation of group differences. Individually scaled %FMD using the Atkinson scaling resulted in values that were corrected for variations in Dbase but that were twofold to threefold larger than those of the Traditional calculation. New scaling %FMD resulted in values that were similar to values expected (Y: 6·21 ± 2·75%; O: 3·98 ± 1·36%); however, it did not effectively correct for variation in Dbase. Recommendations regarding the advantages of allometrically scaling %FMD should be made with caution until research clearly establishes the benefits of this approach. 相似文献
82.
Correct allometric analysis is always helpful for scaling flow‐mediated dilation in research and individual patient contexts 下载免费PDF全文
Lorenzo Lolli Alan M. Batterham Greg Atkinson 《Clinical physiology and functional imaging》2018,38(5):907-910
McLay et al. (Clin Physiol Funct Imaging (2017); DOI: 10.1111/cpf.12465 ) recently examined whether the allometric scaling of flow‐mediated dilation influenced the mean difference between samples of young and older adults compared with the traditional percentage change approach. They also explored whether a new scaling calculation improved the ability to obtain individually scaled flow‐mediated dilation. In our response to their study, we can demonstrate that McLay et al. (Clin Physiol Funct Imaging, 2017) have (i) managed to formulate a new scaling index which does nothing to remove the dependency of that index on baseline diameter and (ii) suggested, incorrectly, that the original allometric approach cannot be used to derive individually‐adjusted values of flow‐mediated dilation, which can be interpreted in a similar way to a percentage change. 相似文献
83.
84.
内镜下取石气囊扩张法治疗胆总管结石 总被引:2,自引:1,他引:2
目的 探讨内镜下取石气囊扩张 (EBD)治疗胆总管结石的可能性、有效性及安全性。方法 对 4 7例胆总管结石患者进行了内镜下以取石气囊扩张Oddi括约肌及用气囊、网篮及机械碎石等方法取石治疗。为预防并发胰腺炎 ,术后酌情应用了善得定、鼻胆管引流及十二指肠乳头小切开等措施。结果 本组患者EBD治疗胆总管结石的成功率为 91 5 % ( 4 3 / 4 7)。一次EBD治疗后 4 1例 ( 87 2 % )结石全部取出 ,有 2例 ( 4 3 % )患者经第 2次EBD治疗后将结石全部取出 ,避免了内镜下乳头括约肌切开 (EST)。 4 7例患者中 2 7例 ( 5 7 4 % )结石直径大于 1 0cm ,施行了机械碎石术。 4例 ( 8 5 % )患者因结石太大 (≥ 2 0cm ) ,EBD治疗未成功 ,改行EST取出结石。本组患者无穿孔及出血并发症。 11例 ( 2 3 4 % )术后血清淀粉酶一过性升高 ,其中只有 1例伴有腹痛 ,经内科保守治疗迅速缓解。结论 EBD治疗胆总管结石可行、有效、安全。 相似文献
85.
《Respiratory investigation》2020,58(1):68-73
BackgroundVarious procedures for bronchoalveolar lavage (BAL) have been developed. BAL needs a wedge between the bronchoscope and the inner surface of the bronchus. The feasibility of performing BAL at the targeted position cannot be determined until immediately before the procedure. We examined BAL performed using a balloon catheter to evaluate the stability of the procedure itself and quality of the specimen obtained.MethodsThe main inclusion criteria were diffuse lung disease with a shadow in the B5a area. The tip of a disposable balloon catheter was passed through the orifice of the B5a bronchus, and the balloon was expanded at the B5a bronchus. A 50-mL syringe containing saline was instilled, and gentle hand suction was performed. This procedure was repeated two more times (total: 150 mL).ResultsIn all the 13 patients, the balloon of the catheter was inflated at the B5a bronchus. The median recovery rate was 34.92% ± 13.22%. These values were comparable to previously obtained BAL data (control group, N = 56) from our facility. The BAL fluid findings and final diagnosis, with the exception of one undiagnosed case, were consistent. Overall, four patients suffered an adverse event during BAL (hypoxemia). All cases were managed by increasing the oxygen flow rate, and the adverse event did not affect the subsequent examinations.ConclusionsUsing a balloon catheter enabled us to perform BAL at the intended bronchus. The quality of the obtained specimen was also acceptable. 相似文献
86.
背景:结直肠扩张可影响自主神经系统的活动,而心率变异性(HRV)可反映自主神经系统的功能状态。目的:探讨结直肠扩张对自主神经功能的影响,以及替加色罗对自主神经功能的调节作用。方法:18只成年雄性大鼠随机分为药物组(腹腔注射替加色罗)和溶媒对照组,清醒状态下记录心电信号,通过HRV频域分析比较两组大鼠结直肠扩张前后交感神经张力[P1/(P1 P2)]和迷走神经张力[P2/(P1 P2)]的变化。结果:在溶媒对照组,与基础状态相比,结直肠扩张能显著提高P1/(P1 P2)(0.326±0.141对0.403±0.142,P<0.05),降低P2/(P1 P2)(0.674±0.141对0.597±0.142,P<0.05);腹腔注射替加色罗后,扩张期的P1/(P1 P2)和P2/(P1 P2)与基础状态相比无显著变化(0.293±0.130对0.275±0.103, P>0.05;0.706±0.130对0.724±0.103,P>0.05)。结论:结直肠扩张可显著提高交感神经张力,降低迷走神经张力。替加色罗对结直肠扩张所致的自主神经张力变化有抑制作用。 相似文献
87.
Endoscopic pancreatic sphincter balloon dilation for effective retrieval of pancreatic duct stone 总被引:9,自引:0,他引:9
Suga T Kawa S Horiuchi A Nakamura N Mukawa K Akamatsu T Kiyosawa K 《Journal of gastroenterology and hepatology》2000,15(2):220-224
To facilitate pancreatic stone retrieval, four patients with chronic pancreatitis and pancreatic stones underwent endoscopic pancreatic sphincter balloon dilation (EPSBD) rather than pancreatic sphincterotomy. Extracorporeal shock wave lithotripsy combined with endoscopic removal was carried out in three patients. Stone removal following EPSBD was completely successful in all four patients. Patients showed no severe complications during the dilation procedure. In one patient, to prevent pancreatitis, an endoscopic nasopancreatic drain was placed for 1 week after EPSBD. Compared with pancreatic sphincterotomy, EPSBD can be performed safely in patients with chronic pancreatitis to assist in the extraction of pancreatic duct stones. Use of the EPSBD procedure in cases of chronic pancreatitis provides a useful approach to improve endoscopic clearance of pancreatic duct stones. 相似文献
88.
对19例劳力型心痛病人给予尼可地尔口服2周,通过卧位踏车试验观运动心电图二尖瓣口多普勒血流变化。用药后S-5段下降消失时间,运动持续时间及运动工作负荷明显改善,静息及运动工作后A/E比,E峰减时间及减速度明显改善,表明尼可地尔能改善冠心病人的左室舒张功能,提高运动耐力。 相似文献
89.
Domajnko B Ahrendt SA 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2005,7(4):292-297
Primary sclerosing cholangitis (PCS) is a progressive disease leading to secondary biliary cirrhosis. Patients are at increased risk of developing cholangiocarcinoma, which is usually diagnosed at an advanced stage. Treatment of PCS includes medical therapy, endoscopic biliary dilation, percutaneous transhepatic stenting, extrahepatic biliary resection and liver transplantation. The most effective management of primary sclerosing cholangitis before the onset of cirrhosis remains unclear. Non-transplant surgical procedures have a limited but defined role in patients with PCS. Resection of the extrahepatic biliary tree in symptomatic non-cirrhotic patients improves hyperbilirubinaemia and prolongs both transplant-free and overall survival when compared with non-operative dilation and/or stenting. Surgical resection may also definitively establish or exclude a diagnosis of cholangiocarcinoma in patients with dominant extrahepatic or perihilar strictures. Extrahepatic bile duct resection may also reduce the risk of cholangiocarcinoma. Extrahepatic biliary resection should be considered in selected non-cirrhotic patients with symptomatic biliary obstruction and dominant extrahepatic and/or perihilar strictures. Those patients in whom cholangiocarcinoma is suspected should also undergo resection. 相似文献
90.
目的:采用高分辨率超声技术探讨病毒性心肌炎患者血流介导的肱动脉舒张反应(FMD)和硝酸甘油介导的肱动脉舒张反应(NMD).方法:采用高分辨率超声技术检测30例病毒性心肌炎患者(心肌炎组)的内皮功能,并与20例非心肌炎患者(非心肌炎组)及20例健康体检者(正常对照组)做比较.结果:心肌炎组FMD(8.73±2.87)%和非心肌炎组FMD(13.00±2.79)%均低于正常对照组(19.32±2.67)%,且差异有统计学意义(P均<0.01),心肌炎组FMD低于非心肌炎组,差异有统计学意义(P<0.01).心肌炎组NMD(19.68±5.84)%、非心肌炎组NMD(23.18±4.28)%及正常对照组NMD(24.24±4.13)%3组比较差异无统计学意义(P>0.05).结论:病毒性心肌炎患者血管内皮依赖性舒张功能受损明显,而非内皮依赖性舒张功能变化不明显. 相似文献