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1.

Background

Photosensitizers used for photodynamic therapy (PDT) to treat dermatologic disease are metabolized into mainly protoporphyrin IX (PpIX), which has five absorption wavelength peaks: 410?nm, 510?nm, 545?nm, 580?nm, and 630?nm. Although only red light around 635?nm and blue light around 400?nm are used as light sources for PDT, the efficiency of PDT might be improved by using multiple wavelengths, including those that correspond to the other absorption peaks of PpIX. Furthermore, because the target disease often occurs on the face, a flexible-type light-source unit that can be fitted to the lesion without unnecessarily exposing the mucous membranes, e.g., the eyes, nostrils, and mouth, is preferred.

Objective

We investigated the efficacy of a flexible light-emitting diode (LED) unit that emits multiple wavelengths to improve PDT effects.

Methods

HaCaT cells were incubated with 5-ALA and subsequently irradiated with either a single wavelength or sequentially with two wavelengths. Cell viability and reactive oxygen species were analyzed. Nude mice were implanted with COLO679 cells by subcutaneous injection into the flank. 5-ALA was subcutaneously injected into the tumor. The tumor was irradiated with 50?J/cm2 (day 0) and assessed daily until day 21.

Results

The synergistic PDT effects of dual-wavelength irradiation and reactive oxygen species production were highest with the 405-nm and 505-nm wavelength combination. This dual wavelength combination was also the most effective in vivo.

Conclusion

We could therefore conclude that dual-wavelength PDT is an efficient strategy for improving the therapeutic effects of PDT. Using a flexible LED unit is expected to achieve more uniform irradiation of uneven areas.  相似文献   
2.
3种微创手术治疗复杂性输尿管上段结石的疗效比较   总被引:1,自引:0,他引:1  
目的比较经尿道输尿管镜钬激光碎石(URSL)联合体外冲击波碎石(ESWL)、微创经皮肾镜取石(mini-PCNL)、后腹腔镜输尿管切开取石术(RLU)治疗复杂性输尿管上段结石的疗效。方法153例复杂性输尿管上段结石患者按治疗方法分为三组:URSL联合ESWL(联合组)治疗60例,mini-PCNL治疗65例,RLU治疗28例。结果联合组有5例转开放手术取石,余50例患者平均手术时间(65.45±16.39)min,术后并发症发生率为23.64%(13/55),1个月后结石清除率为90.91%(50/55)。mini-PCNL组无中转,平均手术时间(50.38±12.91)min,术后并发症发生率为9.23%(6/65),1个月后结石清除率为100%。RLU组有2例转开放取石,平均手术时间(81.73±17.89)min,术后并发症发生率为15.38%(4/26),1个月后结石清除率为100%(26/26)。mini-PCNL组的手术时间、术后住院时间均显著短于联合组和RLU组;并发症发生率明显低于联合组;1个月后结石清除率明显高于联合组。结论mini-PCNL治疗复杂性输尿管上段结石具有手术时间短、结石清除率高、术后并发症少、恢复快的优点。  相似文献   
3.
The design of a low-order dynamic output feedback controller for a flexible spacecraft is carried out using modified linear quadratic Gaussian (LQG) theory. The necessary conditions for optimization are given. The linear equations governing a flexible spacecraft with a central rigid body and two sun-tracking solar panels are presented. The parameters of the Solar Electric Propulsion Spacecraft (SEPS) are selected for analysis and simulation. The optimal gains for the dynamic controller are estimated using an iterative algorithm. The sequential procedure which assures convergence is selected. The initial gains which stabilize the system are chosen on the basis of the principle of a PD controller. A third-order controller for pitch, roll and yaw axes of the 18th-order system, which includes sensor and actuator dynamics, is designed. Numerical simulations carried out to ascertain the performance of the controller show the performance to be satisfactory.  相似文献   
4.
The two-stage synthesis of a multi-input/multi-output optimal proportional-integral (PI) controller is described for linear, time-invariant systems. In the first stage the PI controller is designed by solving a steady state algebraic Riccati equation. As a result, the optimal cost is expressed in terms of the system's constant output set-points. In the second stage the cost is further reduced by optimally selecting the output set-points to minimize a static quadratic performance index subject to linear algebraic constraints. The design framework is applied to a planar redundant robotic manipulator equipped with four joints and mounted at the tip of a long flexible arm. We then address the problem of self-motion control in the presence of vibratory disturbances.  相似文献   
5.
通过建立健全医院层面应急管理体系,建立医疗器械供应链预警机制,进行医院内外部动态管理,以信息化提高供应链可视性,可实现医疗器械供应链弹性管理。该管理模式能够有效确保供应链稳定性和可恢复性,进而提升医院应急防控能力,最终保障患者和医务人员安全。  相似文献   
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BackgroundTo evaluate whether stone extraction with a loop ureteral catheter (LUC) in distal ureteral stones is associated with a higher frequency of ureteral strictures compared to treatment with primary ureteroscopic stone removal (p-URS) or ureteroscopic laser lithotripsy (l-URS).MethodsFive hundred and forty-seven consecutive patients were primarily endourologically treated for distal ureteral stones in our department between 2005 and 2019 and included in the study protocol. Data was retrospectively obtained from the patients’ charts and medical reports as well as from office-based urologists. Data analysis was performed using Fisher’s exact test, Mann-Whitney test or Student’s t-test as appropriate. A level of P<0.05 was assigned statistical significance.ResultsFour hundred and twelve patients were treated by URS (p-URS n=304, l-URS n=108) and another 135 by LUC stone extraction. Median follow-up was 41 [2–159] months. There was no difference between the groups concerning age, gender, proportion of patients with ureteral stenting, operating time, hospitalization or readmission rates. The number of ureteric strictures was small in all procedures [n=3 (1.0%) in p-URS, n=2 (1.9%) in l-URS and n=2 (1.5%) in LUC] and there was no difference between the groups concerning this serious complication (p-URS vs. LUC: P=0.6465; l-URS vs. LUC: P=0.9999).ConclusionsIn small distal stones, LUC stone extraction still is an alternative to URS procedures in stone management with comparable results concerning postinterventional ureteral strictures. In experienced hands, it still has its value in accurately selected patients.  相似文献   
9.
目的 为探讨弹性材料在修复前牙缺失中的临床效果,进一步推广应用弹性材料在口腔修复美容中的价值。方法 利用美国Valpast公司研制的弹性材料,湖南长沙AULEN公司生产的隐形义齿机。选择前牙缺失患者216例,按临床要求制备基牙工作模型,制作蜡型装合,加热去腊后灌注弹性材料,冷却后取出铸件修整抛光。结果 216例患者修复298颗牙,两年后随访168例,优良者156例,占92.86%;一般者8例,占4.76%;较差者4例,占2.38%。结论 本方法修复前牙缺失与传统方法相比,无需金属卡环支架固位,具有美观、舒适、超薄、耐磨、制作快捷、简单等优点,是修复前牙缺失的理想材料及方法,值得临床推广应用。  相似文献   
10.
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