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991.
《Seminars in Fetal & Neonatal Medicine》2018,23(2):85-93
Screening for fetal chromosomal disorders has evolved greatly over the last four decades. Initially, only maternal age-related risks of aneuploidy were provided to patients. This was followed by screening with maternal serum analytes and ultrasound markers, followed by the introduction and rapid uptake of maternal plasma cell-free DNA-based screening. Studies continue to demonstrate that cfDNA screening for common aneuploidies has impressive detection rates with low false-positive rates. The technology continues to push the boundaries of prenatal screening as it is now possible to screen for less common aneuploidies and subchromosomal disorders. The optimal method for incorporating cfDNA screening into existing programs continues to be debated. It is important that obstetricians understand the biological foundations and limitations of this technology and provide patients with up-to-date information regarding cfDNA screening. 相似文献
992.
Lawrence G. Rudski Luna Gargani William F. Armstrong Patrizio Lancellotti Steven J. Lester Ekkehard Grünig Michele DAlto Meriam ?str?m Aneq Francesco Ferrara Rajeev Saggar Rajan Saggar Robert Naeije Eugenio Picano Nelson B. Schiller Eduardo Bossone 《Journal of the American Society of Echocardiography》2018,31(5):527-550.e11
993.
目的实时监测控制性降压对俯卧位脊柱手术全麻患者眼内压及眼底动脉血液动力学的影响,以探讨其安全阈值。方法随机选取预行俯卧位脊柱全麻手术的60例外科患者为研究对象,麻醉过程中采用硝酸甘油控制性降压。选择诱导前10 min(T0)、诱导后10 min(T1)、俯卧位后10 min(T2)、控制性降压10%(T3)、20%(T4)、30%(T5)、恢复正常血压10 min(T6)、术毕平卧位后10 min(T7)、拔出气管导管后10 min(T8)9个时间点,使用笔式眼压计测量眼内压(IOP),使用彩色多普勒超声仪测定右眼视网膜中央动脉和睫状后动脉的血流动力学特征收缩期最高流速(PSV)、舒张末期最低流速(EDV)、阻力指数(RI)及搏动指数(PI)。结果患者诱导麻醉后,IOP、RI及PI随着麻醉时间的延长呈升高趋势,PSV及EDV呈降低趋势,T5时,各指标差异性最大,均较T0有显著差异(P0.05或0.001)。T6后,各指标有所恢复,T8各指标较T0无统计学差异(P0.05)。另外,T5时4例患者出现视网膜中央动脉闭塞(CRAO)征象,其MAP均低于患者该时段平均水平(64.8±8.66 mmHg)。结论控制性降压对俯卧位脊柱手术全麻患者的眼内压及眼底动脉血液动力学指征有所影响,血压降低水平控制在基线水平的30%以内,且保证目标MAP65 mmHg,可有效保护患者视神经。 相似文献
994.
Y. Manda N. Maeda Q. Pan K. Sugimoto Y. Hashimoto Y. Tanaka N. Kodama S. Minagi 《Journal of oral rehabilitation》2016,43(6):417-425
Elevation of the posterior part of the tongue is important for normal deglutition and speech. The purpose of this study was to develop a new surface electromyography (EMG) method to non‐invasively and objectively evaluate activity in the muscles that control lifting movement in the posterior tongue. Neck surface EMG (N‐EMG) was recorded using differential surface electrodes placed on the neck, 1 cm posterior to the posterior border of the mylohyoid muscle on a line orthogonal to the lower border of the mandible. Experiment 1: Three healthy volunteers (three men, mean age 37·7 years) participated in an evaluation of detection method of the posterior tongue lifting up movement. EMG recordings from the masseter, temporalis and submental muscles and N‐EMG revealed that i) N‐EMG was not affected by masseter muscle EMG and ii) N‐EMG activity was not observed during simple jaw opening and tongue protrusion, revealing the functional difference between submental surface EMG and N‐EMG. Experiment 2: Seven healthy volunteers (six men and one woman, mean age 27·9 years) participated in a quantitative evaluation of muscle activity. Tongue‐lifting tasks were perfor‐med, exerting a prescribed force of 20, 50, 100 and 150 gf with visual feedback. For all subjects, a significant linear relationship was observed bet‐ween the tongue‐lifting force and N‐EMG activity (P < 0·01). These findings indicate that N‐EMG can be used to quantify the force of posterior tongue lifting and could be useful to evaluate the effect of tongue rehabilitation in future studies. 相似文献
995.
996.
Stroke volume is a key determinate of cardiac output. It is affected by the preload, contractility and afterload of the myocardium. It is possible to gain insight into the right and left ventricular preload following the insertion of a central venous catheter and pulmonary artery catheter to measure central venous pressure and pulmonary capillary wedge pressure, respectively. Abnormal measurements can indicate a pathophysiological state and guide management. 相似文献
997.
Juhua Xiao Zhen Shi Jinshui Zhou Jun Ye Jianfang Zhu Xin Zhou Fang Wang Shouhua Zhang 《Ultrasound in medicine & biology》2017,43(3):640-647
The aim of this study was to investigate the clinical efficacy of high-intensity focused ultrasound (HIFU) for the treatment of a cesarean scar pregnancy compared with uterine artery embolization (UAE) and intra-arterial methotrexate infusion combined with uterine curettage. In this retrospective cohort study, 31 patients were treated with HIFU (HIFU group), and 45 patients were treated with UAE (UAE group). We compared the treatment and recovery of the patients, including follow-up. After UAE treatment, serum levels of the β subunit of human chorionic gonadotropin declined significantly on the first day, and the residual lesions disappeared in 3–17 wk. One patient underwent hysterectomy; intrauterine adhesions were found by hysteroscopic examination after 6 mo in 2 patients, whose menstrual function did not return to normal. The remainder of the 42 patients recovered normal menstrual functioning during the 3- to 18-wk follow-up. In the patients who underwent HIFU treatment, serum β-HCG levels did not decline rapidly; serum β-HCG levels increased in many patients and then declined to normal steadily within 2–12 wk. Lesions detached in 3–14 wk in all patients, and menstrual functioning was recovered in 3–9 wk without uterine curettage. Compared with the UAE group, the HIFU group had less pain and fewer complications; the patients in the HIFU group were not hospitalized or anesthetized and had lower costs. HIFU is an efficient, tolerable and non-invasive treatment. 相似文献
998.
999.
目的 观察负压创面治疗技术(negative pressure wound therapy,NPWT)对刃厚游离皮片移植术后皮片成活率的影响. 方法 对65例皮肤缺损的患者,根据皮肤移植术后皮片固定方法的不同分为两组:其中Ⅰ组为NPWT治疗组(35例),刃厚游离皮片移植术后行创面负压吸引治疗;Ⅱ组为常规治疗组(30例),刃厚游离皮片移植术后用打包或加压包扎的方式固定. 结果 术后第5天皮片成活率比较:Ⅰ组为(80.59±10.30)%,明显高于Ⅱ组的(71.46±10.68)%(P<0.05);术后皮片成活时间比较:Ⅰ组为(5.34±0.87)d,明显少于Ⅱ组的(11.20±1.65)d(P<0.01);术后住院治疗时间比较:Ⅰ组为(10.83±0.82)d,明显少于Ⅱ组的(15.50±1.11)d(P<0.01);术后抗生素费用比较:Ⅰ组为(1 765.71±164.39)元,明显少于Ⅱ组的(2 700.00±221.28)元(P<0.01);术后换药次数及换药费用比较:Ⅰ组为(3.11±0.32)次、(249.14±25.82)元,明显少于Ⅱ组的(4.53±0.68)次、(362.67±54.52)元(P<0.01). 结论 刃厚游离皮片移植术后应用NPWT可以缩短皮片成活时间,缩短患者住院治疗时间,减少抗生素使用及换药次数. 相似文献
1000.