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One challenge for multimodal therapy is to develop appropriate multifunctional agents to meet the requirements of potential applications. Photodynamic therapy (PDT) is proven to be an effective way to treat cancers. Diverse polycations, such as ethylenediamine‐functionalized poly(glycidyl methacrylate) (PGED) with plentiful primary amines, secondary amines, and hydroxyl groups, demonstrate good gene transfection performances. Herein, a series of multifunctional cationic nanoparticles (PRP) consisting of photosensitizer cores and PGED shells are readily developed through simple dopamine‐involving processes for versatile bioapplications. A series of experiments demonstrates that PRP nanoparticles are able to effectively mediate gene delivery in different cell lines. PRP nanoparticles are further validated to possess remarkable capability of combined PDT and gene therapy for complementary tumor treatment. In addition, because of their high dispersities in biological matrix, the PRP nanoparticles can also be used for in vitro and in vivo imaging with minimal aggregation‐caused quenching. Therefore, such flexible nanoplatforms with photosensitizer cores and polycationic shells are very promising for multimodal tumor therapy with high efficacy.  相似文献   
84.
Purpose The aim of this study was to assess the value of contrast-enhanced (c.-e.) MRI in the follow-up of patients with conservatively treated breast cancer since detection and exclusion of malignancy may interfere significantly with posttherapeutic changes within the treated breast. Material and methods A total of 207 patients with a history of limited surgery and radiation therapy underwent MR imaging, 40 patients were examined 0–12 months and 167 patients were examined later than 12 months after radiotherapy. Suspicious or indeterminate findings were suggested by clinical examination or conventional imaging in 80 studies. In 127 women, MRI was performed within breast tissue that was difficult to assess due to scarring or dense breast tissue. Results Recurrent carcinoma was confirmed in 27 patients by surgical biopsy. All 27 carcinomas, except for one with a slow signal increase, demonstrated early rise of signal intensity on dynamic T1-weighted contrast enhanced images. During the first year after therapy, the diagnostic accuracy could not be improved by additional use of c.-e. MRI. Differentiation between posttherapeutic changes and recurrent carcinoma was frequently not possible because of strong and sometimes early and ill-circumscribed enhancement. Later than 12 months after therapy enhancement decreased significantly, thus the false positive calls could be reduced from 49 (conventional imaging) to 12 (conventional imaging plus MRI). A total of 12 of 26 recurrences and multifocality in 4/5 cases were diagnosed by MR imaging alone at this time interval. Conclusion In the first year after therapy, c.-e. MRI is only indicated in selected cases. The results later than 12 months emphasize that c.-e. MRI may contribute significant additional information. It allows better distinction of posttherapeutic fibrosis from recurrent carcinoma and proved to be able to detect recurrent disease more sensitive and at an earlier stage.  相似文献   
85.
对光照射血液疗法的分析与讨论   总被引:1,自引:0,他引:1  
分析对比了低强度激光血管内照射疗法与紫外线血液照射疗法的治疗方法、治疗病种和治疗机制的异同点。以“生物共振”与“光触发”观点解释其治疗机制。从全血吸收光谱出发,提出了实验最佳激光参数疗法,紫餐相干光照射疗法、激光血管外照射法等思路与建议。  相似文献   
86.
Abstract— Light sources with wavelengths from near‐UV to near‐IR can cure skin diseases, relieve pain in the body, reduce wrinkles on the skin, treat acne on the face, grow hairs on head, and heal various kinds of other diseases. This is called phototherapy. Near‐UV, visible, and near‐IR LEDs now enable phototherapy viable for personal use because of the possibility of controlling the intensity of LED light with specific wavelengths. The medical applications of LEDs for phototherapy are reviewed.  相似文献   
87.
艺术是一种用形象来反映现实但比现实有典型性的社会意识形态,而其中的绘画艺术作为一种非语言的沟通工具,可以让观察者了解语言文字无法揭示的东西,同时绘画艺术的存在是与心理完美结合着的,共同服务于人类社会。  相似文献   
88.
眼睛理疗仪智能控制器主要由主控制中心、人机交互系统(包括形状触摸控制、触屏控制、语音控制)、电机驱动模块、红外理疗模块、电磁理疗模块、音乐模块组成。主控中心通过压力传感器、温度传感器、加速度传感器实时监测各项参数。理疗仪具有多种理疗方式:振动按摩、穴位定点按摩、硅胶体滑动按摩、红外理疗、电磁理疗,以及上述方式的任意组合。通过合理的软件算法,实现控制方式的智能化、人性化,实现理疗效果的最佳化。  相似文献   
89.
While OLEDs have struggled to find a niche lighting application that can fully take advantage of their unique form factors as thin, flexible, lightweight and uniformly large‐area luminaire, photomedical researchers have been in search of low‐cost, effective illumination devices with such form factors that could facilitate widespread clinical applications of photodynamic therapy (PDT) or photobiomodulation (PBM). Although existing OLEDs with either fluorescent or phosphorescent emitters cannot achieve the required high power density at the right wavelength windows for photomedicine, the recently developed ultrabright and efficient deep red quantum dot light emitting devices (QLEDs) can nicely fit into this niche. Here, we report for the first time the in‐vitro study to demonstrate that this QLED‐based photomedical approach could increase cell metabolism over control systems for PBM and kill cancerous cells efficiently for PDT. The perspective of developing wavelength‐specific, flexible QLEDs for two critical photomedical fields (wound repair and cancer treatment) will be presented with their potential impacts summarized. The work promises to generate flexible QLED‐based light sources that could enable the widespread use and clinical acceptance of photomedical strategies including PDT and PBM.  相似文献   
90.
通过SolidWorks建立某心脏瓣膜支架的三维模型,用Abaqus对瓣膜支架压握入鞘过程与疲劳情况进行分析,得到支架的应变分布和疲劳性能.结果可以判断支架设计的优劣,为支架优化设计提供参考.  相似文献   
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