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991.
Gastric cancer was one of the most common malicious diseases around the world1. Photodynamic therapy (PDT) has been applied to the treatment of gastric tumors since 1980’s and desirable results has been obtained. Hypocrellin B (HB), the natural perylenequinone pigment (PQP), was found to be new effective sensitizer in the photodynamic therapy by virtue of its photophysical, photochemical and photobiological properties2. Scheme 1. The structures of AHBDs AHBDsNevertheless, natural PQP…  相似文献   
992.
In radiation cancer therapies using energetic charged particles such as proton/heavy-ion therapy and boron neutron capture therapy (BNCT), studies on radiation-induced biological response at cellular level are important because the radiation damage from energetic charged particles is highly localized along their paths and the radiation sensitivity is quite different in each cellular organelle. In such studies the information on the position of charged particle impact in biological cells is necessary. A novel method for high-resolution nuclear track mapping in detailed cellular histology has been developed. In this technique, biological specimens mounted on CR-39 plates are exposed to energetic charged particles. The irradiated samples are exposed to UV, and then etched for a short time. Both etch pits of nuclear tracks and relief for transmission UV image of the specimen can be observed on the CR-39 surface with an atomic force microscope (AFM) at about 100 nm resolution.  相似文献   
993.
The quality cycle requires clinicians to assess the outcomes of interventions. Benchmarking is an approach that has been advocated to compare current performance across different services to identify commonalities and significant differences. This article gives the results of a study of outcomes in speech and language therapy (SLT) using the therapy outcome measure (TOM) for patients with voice disorder (dysphonia) comparing outcomes of seven separate speech and language therapy services. The study aimed to identify the similarities and differences in outcomes of care provided by different services. Two hundred and forty patients with dysphonia (age range 3-87.5 years, average 51.9 years) were treated. The results indicated that although there was no significant difference in the profile of the severity of symptomology of patients referred to speech and language therapy in different geographical areas, there was a significant difference in the treatment outcomes across the services and in the stated reason for discharge from treatment. Nevertheless, most patients with dysphonia had a good outcome and this was associated with completion of the course of treatment. There were significant differences in the number of treatment contacts provided by the different services and in the duration (between admission and discharge) of treatment across the services. Benchmarking can provide useful information through use of routinely collected clinical data.  相似文献   
994.
The purpose of the current study was to determine how maximum phonationduration (MPD) of five notes (C4, D4, E4, F4, 134) sustained on /o/, sustained vowels (/i/, //, /a/, /u/), and s/z ratio (sustained /s/ and /z/ changed during voice therapy for vocal nodules. Voices of adult females before treatment and after resolution of vocal nodules were analyzed via the PM Pitch Analyzer. Treatment included tension reduction, abuse identification and elimination, laryngeal strengthening, and home exercises. Results indicate there was no significant difference in maximum phonation duration or S/Z ratio before and after treatment. Results revealed that females with vocal nodules demonstrate measurements before therapy similar to measures considered to be normal in persons without vocal nodules. Application of findings to clinical practice is discussed.  相似文献   
995.
Summary A liposome based gene therapeutic product is being developed for the treatment of cystic fibrosis. The product comprises a complex of plasmid DNA and a cationic lipid/cholesterol liposome. Using CE with an entangled polymer matrix, routine separations of linear, supercoiled and open-circle conformers of DNA in plasmid DNA and the liposome complex have been performed. The CE method has been used to support novel quality control and process validation for the manufacture of plasmid DNA and to monitor the degradation of DNA in the liposome complex. Significant features of the method are simple sample preparation and the use of direct UV detection, avoiding the use of potentially mutagenic reagents.  相似文献   
996.
A novel 1,2‐dicarba‐closo‐dodecaborane–lactose conjugate ( 4a ) with an N‐glycosidic linkage was synthesized. This conjugate was found to be much more stable against hydrolytic deboronation (closo to nido tranformation of the carborane cage) under neutral conditions than a related carborane–lactose conjugate ( 1a ) with an O‐glycosidic linkage. This result demonstrates that the hydrolytic stability of carborane–carbohydrate conjugates in neutral aqueous solutions may depend dramatically on the chemical nature of the spacer that links the carbohydrate moiety with the boron cage, the rate of hydrolysis varying by orders of magnitude. We relate a significant decrease in the deboronation rate to the formation of more strongly bound supramolecular aggregates, in which the boron cage is less accessible to nucleophilic attack by solvent molecules, in the solution of the carborane–N‐lactoside conjugate 4a . Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
997.
The interactions between Chlorophyllide a (Chlide), a pigment having the same structure of Chl a without the phytilic tail, and two CDs having the same moieties but different cavity size, the hydroxypropyl- β -cyclodextrin and the hydroxypropyl-γ-cyclodextrin, were studied in aqueous solutions by means of absorption, fluorescence spectroscopy, circular dichroism and isothermal titration calorimetry. The results obtained indicate that both cyclodextrins are able to modify the aggregation equilibrium of the pigment favouring the monomeric form. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
998.
在栅扫描束流配送系统下, 进行了重离子束对运动靶体进行适形照射的可行性实验研究. 利用实时修正束流扫描参数的方法, 使得束流追踪靶体在横向上的运动; 在纵向上利用一个机械驱动的束流降能装置(称深度扫描器)迅速调节束流 能量, 使得重离子束高剂量的Bragg峰区落在运动靶体需治疗的断层之上. 实验结果表明: 栅扫描器主动补偿靶体横向运动及深度扫描器补偿靶体纵向运动是可行的.  相似文献   
999.
《中国化学》2014,(1):78-84
A water soluble β-cyclodextrin (β-CD) functionalized [60]fullerene (C60-CD) was synthesized.The C60-CD-induced generation of reactive oxygen species (ROS),and DNA-cleavage ability and cytotoxicity of C60-CD were studied upon visible light irradiation,demonstrating that the compound is very promising in the applications of photodynamic therapy.The histological analyses demonstrate that C60-CD has no acute or subacute toxicity to living body.  相似文献   
1000.
The main photophysical properties of a series of recently synthetized 1,2‐ and 1,3‐squaraines, including absorption electronic spectra, singlet‐triplet energy gaps, and spin‐orbit matrix elements, have been investigated by means of density functional theory (DFT) and time‐dependent DFT approaches. A benchmark of three exchange‐correlation functionals has been performed in six different solvent environments. The investigated 1,2 squaraines have been found to possess two excited triplet states (T1 and T2) that lie below the energy of the excited singlet one (S1). The radiationless intersystem spin crossing efficiency is thus enhanced in both the studied systems and both the transitions could contribute to the excited singlet oxygen production. Moreover, they have a singlet‐triplet energy gap higher than that required to generate the cytotoxic singlet oxygen species. According to our data, these compounds could be used in photodynamic therapy applications that do not require high tissue penetration. © 2014 Wiley Periodicals, Inc.  相似文献   
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