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61.
Fractional radiofrequency microneedling is a novel radiofrequency technique that uses insulated microneedles to deliver energy to the deep dermis at the point of penetration without destruction of the epidermis. It has been used for the treatment of various dermatological conditions including wrinkles, atrophic scars and hypertrophic scars. There have been few studies evaluating the efficacy of fractional radiofrequency microneedling in the treatment of acne, and none measuring objective parameters like the number of inflammatory and non‐inflammatory acne lesions or sebum excretion levels. The safety and efficacy of fractional radiofrequency microneedling in the treatment of acne vulgaris was investigated. In a prospective clinical trial, 25 patients with moderate to severe acne were treated with fractional radiofrequency microneedling. The procedure was carried out three times at 1‐month intervals. Acne lesion count, subjective satisfaction score, sebum excretion level and adverse effects were assessed at baseline and at 4, 8 and 12 weeks after the first treatment as well as 4, 8 and 12 weeks after the last treatment. Number of acne lesions (inflammatory and non‐inflammatory) decreased. Sebum excretion and subjective satisfaction were more favorable at every time point compared with the baseline values (< 0.05). Inflammatory lesions responded better than non‐inflammatory lesions (P < 0.05). Adverse effects such as pinpoint bleeding, pain and erythema were noted, but were transient and not severe enough to stop treatment. Fractional radiofrequency microneedling is a safe and effective treatment for acne vulgaris.  相似文献   
62.
目的探讨恒速滴注法在高龄卧床管饲患者中的应用效果。方法2010年5月至2011年8月,方便性抽样选择在解放军总医院住院治疗的携带鼻胃管或鼻肠管行胃肠营养的老年患者60例,按入院先后分为观察组和对照组各30例,观察组采用恒速滴注法管饲肠内营养乳剂,对照组采用常规管饲方法即分次推注法,观察并比较两组患者堵管、腹胀、腹泻、反流、误吸等并发症的发生率。结果观察组患者发生堵管、反流及误吸的例数均少于对照组,差异均有统计学意义(均P〈0.05);发生腹胀与腹泻的例数与对照组比较,差异无统计学意义(均P〉0.05)。结论恒速滴注法肠内营养可有效满足高龄长期卧床患者的营养需求,预防和减少并发症的发生,推荐在临床广泛应用。  相似文献   
63.
Coronary computed tomography angiography (CCTA) has been an established noninvasive method for detection of coronary artery disease (CAD). Although CCTA has had a high sensitivity and negative predictive value for CAD detection, specificity for obstructive CAD has been relatively low, partly due to coronary calcium, imaging artifacts, and other factors leading to an overestimation of stenosis severity. A relatively new noninvasive method of calculation of fractional flow reserve (FFR) using CCTA (FFRCT) data has been developed. This noninvasive method yields similar results to invasive FFR measurement, improving specificity for noninvasively detecting lesion‐specific ischemia thus helping guide revascularization.  相似文献   
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目的:观察非剥脱1550nm铒玻璃点阵激光治疗活动性痤疮及痤疮凹陷性瘢痕的临床疗效及安全性。方法:应用非剥脱性1550nm铒玻璃点阵激光治疗中重度痤疮患者25例,其中16例表现为活动性痤疮皮损(粉刺、丘疹、脓疱、结节)合并痤疮后凹陷性瘢痕,3例为痤疮瘢痕不伴活动性皮损,6例为活动性皮损不伴瘢痕形成。治疗1-3次,每次间隔3-4周,于末次治疗1个月后观察疗效。结果:活动性皮损22例,痊愈2例(9.1%)、显效14例(63.6%)、有效6例(27.3%)、无效或恶化0例(O%),总有效率为72.7%;痤疮凹陷性瘢痕19例,痊愈2例(10.5%)、显效10例(52.6%)、有效7例(36.8%)、无效或恶化0例(0%),总有效率为63.2%。且随着治疗次数的增加疗效逐步提高。术后仅出现轻度红肿,平均2-3天消退,均无色素沉着、水疱等不良反应,无1例恶化,患者满意率达840。结论:非剥脱1550nm铒玻璃点阵激光治疗活动性痤疮及痤疮后凹陷性瘢痕均有显著疗效,且安全、不艮反应轻,患者满意率高。  相似文献   
68.
BackgroundMechanisms of scar-related ventricular tachycardia (VT) are largely based on computational and animal models that portray a 2-dimensional view.ObjectivesThe authors sought to delineate the human VT circuit with a 3-dimensional perspective from recordings obtained by simultaneous endocardial and epicardial mapping.MethodsHigh-resolution mapping was performed during 97 procedures in 89 patients with structural heart disease. Circuits were characterized by systematic isochronal analysis to estimate the dimensions of the isthmus and extent of the exit region recorded on both myocardial surfaces.ResultsA total of 151 VT morphologies were mapped, of which 83 underwent simultaneous endocardial and epicardial mapping; 17% of circuits activated in a 2-dimensional plane, restricted to 1 myocardial surface. Three-dimensional activation patterns with nonuniform transmural propagation were observed in 61% of circuits with only 4% showing transmurally uniform activation, and 18% exhibiting focal activation patterns consistent with mid-myocardial reentry. The dimensions of the central isthmus were 17 mm (12 to 28 mm) × 10 mm (9 to 19 mm) with 55% exhibiting a minimal dimension of <1.5 cm. QRS activation was transmural in 63% and located 43 mm (34 to 52 mm) from the central isthmus. On the basis of 6 proposed definitions for epicardial VT, the prevalence of an epicardial circuit ranged from 21% to 80% in ischemic cardiomyopathy and 28% to 77% in nonischemic cardiomyopathy.ConclusionsA 2D perspective oversimplifies the electrophysiological circuit responsible for reentrant human VT and simultaneous endocardial and epicardial mapping facilitates inferences about mid-myocardial activation. Intricate activation patterns are frequently observed on both myocardial surfaces, and the epicardium is functionally involved in the majority of circuits. Human reentry may exist within isthmus dimensions smaller than 1 cm, whereas QRS activation is often transmural and remote from the critical isthmus target. A 3-dimensional perspective of the VT circuit may enhance the precision of ablative therapy and may support a greater role for adjunctive strategies and technology to address arrhythmogenic tissue harbored in the mid-myocardium and subepicardium.  相似文献   
69.
Purpose: We used an impedance-controlled generator with an internally cooled electrode to perform radiofrequency ablation (RFA) in ex vivo bovine livers, with a single injection of either 38.5% sodium chloride (NaCl) or 10% hydrochloric acid (HCl), to determine the relative effects of these two solutions on tissue impedance, temperature and ablation volume.

Materials and methods: We performed 10 ablations each with injections of NaCl (NaCl-RFA), HCl (HCl-RFA) or nothing (RFA-alone), with a power setting of 200 W for 15?minutes. We recorded tissue impedance before and after injection. We logged temperatures obtained from thermocouple probes positioned 5, 10, 15 and 20?mm from the internally cooled RF electrode. After ablation, we measured ablation zone longitudinal and transverse diameters, and we calculated a spherical ratio (SR) for each ablation.

Results: Mean post-injection impedance of 30.3 (standard deviation [SD] 2.5) ohms for HCl was significantly lower than that of 55.4 (SD 3.5) ohms for NaCl (p?<?.001). Mean maximum temperatures recorded at each respective distance from the RFA electrode were all highest for HCl-RFA and lowest for RFA-alone (p?<?.001). Mean longitudinal and transverse diameters after HCl-RFA (5.50 [SD 0.25] cm and 5.28 [SD 0.22] cm, respectively) were significantly larger than those after NaCl-RFA (4.24 [SD 0.35] cm and 3.55 [SD 0.43] cm, respectively) and after RFA-alone (3.60 [SD 0.10] cm and 2.70 [SD 0.13] cm, respectively) (p?<?.001). Mean SR after HCl-RFA (0.93, SD 0.02) was significantly higher than mean SR after NaCl-RFA (0.76, SD 0.06) and RFA-alone (0.72, SD 0.04) (p?<?.001).

Conclusion: Monopolar, impedance-controlled RFA, with an internally cooled electrode and a single 10% HCl injection may allow larger tumors to be treated, potentially resulting in improved patient outcomes.  相似文献   

70.
Neisseria gonorrhoeae quickly develops drug resistance. Time-kill curves revealed that EDTA and TOL-463 inhibit growth similar to penicillin, ciprofloxacin, and azithromycin. Furthermore, synergistic and additive antimicrobial interactions occurred when EDTA and TOL-463 were combined with penicillin or azithromycin, respectively, suggesting that further investigations into these unconventional antimicrobials may be advantageous.  相似文献   
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