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1.
M.N. Kotby S.R. El-Sady S.E. Basiouny Y.A. Abou-Rass M.A. Hegazi 《Journal of voice》1991,5(4):316-320
The management of voice disorders may follow one of four approaches: surgical, pharmacological, technical aid, and/or voice therapy. The latter approach offers a wide variety of techniques, each based on certain theoretical beliefs. One of these techniques is the Smith Accent Method. The principles and goals of the Accent Method are presented. The results of its application are discussed. This technique proved effective for cases of functional voice disorders, vocal nodules, and some degrees of vocal fold paralysis. 相似文献
2.
Roland A. Obermüller Christoph Etzlstorfer Heinz Falk 《Monatshefte für Chemie / Chemical Monthly》2002,133(1):89-96
Summary. A hypericin derivative was synthesized in which instead of the methyl groups two benzene rings were condensed to the chromophoric
system in order to extend its conjugation. This derivative showed lowered fluorescence and concomitantly enhanced sensitized
production of active oxygen species as compared to hypericin. However, in contrast to intuition its long wavelength band remained
unshifted in comparison to its parent compound hypericin. Geometry and absorption properties were also investigated by means
of semiempirical calculations.
Received July 27, 2001. Accepted August 9, 2001 相似文献
3.
Bernd?Lackner Yulita?Popova Christoph?Etzlstorfer Andrija A.?Smelcerovic Christian W.?Klampfl Heinz?FalkEmail author 《Monatshefte für Chemie / Chemical Monthly》2005,136(5):777-793
Summary. The syntheses of the two heterocyclically substituted title hypericin derivatives were achieved starting either from 6-benzothiazolyl-tri-O-methyl-6-demethylemodin or 6-benzoxazolyl-tri-O-methyl-6-demethylemodin. The use of microwave assisted synthesis for the preparation of these anthraquinone synthons and the chemical as well as photochemical properties of the corresponding unique hypericin derivatives, which might constitute new photodynamic therapy agents, are reported. The tautomeric and stereochemical aspects of these hypericin derivatives were investigated by means of semiempirical calculations (AM1). 相似文献
4.
D. Brault C. Vever-Bizet K. Kuzelova 《Journal of photochemistry and photobiology. B, Biology》1993,20(2-3):191-195
The interactions of dicarboxylic porphyrins with membrane systems are discussed with particular emphasis on the effect of the charge of the porphyrin and the nature of the side-chains. The incorporation of hematoporphyrin or related dicarboxylic porphyrins within small unilamellar vesicles as membrane models is favored by a decrease of the pH in the range of physiological pH values. This effect might play an important role in the retention of porphyrins by tumors, which are more acidic than normal tissues. Kinetics studies also show that the partition of the porphyrin between the lipidic bilayer and the aqueous phase is governed by its release rate rather than by its incorporation rate. 相似文献
5.
5-Aminolaevulinic acid-mediated photodynamic therapy in multidrug resistant leukemia cells 总被引:5,自引:0,他引:5
Li W Zhang WJ Ohnishi K Yamada I Ohno R Hashimoto K 《Journal of photochemistry and photobiology. B, Biology》2001,60(2-3):79-86
To verify if photodynamic therapy (PDT) could overcome multidrug resistance (MDR) when it it applied to eradicate minimal residual disease in patients with leukemia, we investigated the fluorescence kinetics of 5-aminolaevulinic acid (ALA)-induced protoporphyrin IX (PpIX) and the effect of subsequent photodynamic therapy on MDR leukemia cells, which express P-glycoprotein (P-gp), as well as on their parent cells. Evaluation of PpIX accumulation by flow cytometry showed that PpIX accumulated at higher levels in mdr-1 gene-transduced MDR cells (NB4/MDR) and at lower levels in doxorubicin-induced MDR cells (NOMO-1/ADR) than in their parent cells. A P-gp inhibitor could not increase PpIX accumulation. Measurement of extracellular PpIX concentration by fluorescence spectrometry showed that P-gp did not mediate the fluorescence kinetics of ALA-induced PpIX production. Assessment of ferrochelatase activity using high-performance liquid chromatography indicated that PpIX accumulation in drug-induced MDR cells was probably regulated by this enzyme. Assessment of phototoxicity of PDT using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that PDT was effective in NB4, NB4/MDR, NOMO-1 and NOMO-1/ADR cells, which accumulated high levels of PpIX, but not effective in K562 and K562/ADR cell lines, which accumulated relatively low levels of PpIX. These findings demonstrate that P-gp does not mediate the ALA-fluorescence kinetics, and multidrug resistant leukemia cells do not have cross-resistance to ALA-PDT. 相似文献
6.
Junkai Zhao Xuan Chen Kwun-Hei Ho Chao Cai Cheuk-Wing Li Mo Yang Changqing Yi 《中国化学快报》2021,32(1):66-86
Rheumatoid arthritis(RA),as a chronic autoimmune disease,damages the bone and cartilage of patients,and even leads to disability.Therefore,the diagnosis and treatment of RA is particularly important.However,due to the complexity of RA,it is difficult to make effective early diagnosis of RA,which is detrimental to RA treatment.Besides,long-term intake of anti-RA drugs can also cause damage to patients' organs.The emergence of nanotechnology provides the new train of thoughts for the diagnosis and treatment of RA.And the combination of diagnosis and therapy is an ideal method to solve the problem of disease management of RA patients.In this review,we summarize the mechanism and microenvironment of RA,discuss the commonly used diagnostic techniques and therapeutic drugs for RA,and review their advantages and disadvantages.New nanotherapy strategies such as drug-carrying nanoparticles,PTT,PDT are listed,and their applications in RA treatment are also summarized.In addition,multimodal imaging,combined therapy and responsive diagnosis and treatment are also summarized as important contents.At last,we also review typical nanocarriers that can be used in the integration of diagnosis and therapy,and discussed their potential applications in RA theranostics. 相似文献
7.
Carla Marisa Brito Carvalho Marta Akemi FujitaTimothy John Brocksom Kleber Thiago de Oliveira 《Tetrahedron》2013
New β-fused uracil-porphyrin conjugates were synthesized by the tetramerization of uracil-pyrroles under acidic conditions. Two different synthetic approaches were systematically studied in order to evaluate their efficiency, as well as the possibility to obtain a single regioisomer. Metallation effects were studied for aggregation in solution, and preliminary photophysical experiments were also performed in order to evaluate the potential of these new compounds. 相似文献
8.
Vincent Sol Alexandre Charmot Pierre Krausz Stéphane Trombotto Yves Queneau 《Journal of carbohydrate chemistry》2013,32(4):345-360
This paper presents the synthesis of two new glucosyl tritolylporphyrins in which the carbohydrate moiety is connected through a carboxymethyl glycosidic α‐D‐linkage. These compounds have been obtained by reaction between porphyrins bearing an amino function with a lactone prepared from the available disaccharide isomaltulose. The photocytotoxicity of these compounds against K562 human chronic myelogenous leukemia cells has been evaluated in comparison to Photofrin II. 相似文献
9.
Photodynamic therapy (PDT) has been received broad attentions as a cancer treatment, and fullerenes are potential photosensitizer owing to their unique electronic structures. However, fullerenes show insolubility in water for the special structure, which will induce aggregation to hinder the production of reactive oxygen species (ROS). Furthermore, the size of fullerenes is not conducive to reach the tumors through the enhanced permeability and retention (EPR) effect. Herein, a polyhydroxy fullerene-loaded metal-organic framework is designed and prepared to address the mentioned problems encountering with fullerenes as photosensitizers. The nanocomposite PHF@ZIF-8, which is synthesized by a simple one-pot method, displays great biocompatibility and outstanding photodynamic performance under the 448 nm laser irradiation. This work provides strong evidence for PHF@ZIF-8 as a promising photosensitizer candidate. 相似文献
10.
Kinga Nawalany Aleksandra Rusin Mariusz Kpczyski Alexei Mikhailov Gabriela Kramer-Marek Mirosaw
nietura Jan Potowicz Zdzisaw Krawczyk Maria Nowakowska 《Journal of photochemistry and photobiology. B, Biology》2009,97(1):8-17
Two photosensitizing systems: (1) tetrakis(4-hydroxyphenyl)porphyrin (p-THPP) encapsulated in sterically stabilized liposomes (SSL) and (2) p-THPP functionalized by covalent attachment of poly(ethylene glycol) (p-THPP–PEG2000) were studied in vitro. The dark and photo cytotoxicity of these systems were evaluated on two cell lines: HCT 116, a human colorectal carcinoma cell line, and DU 145, a prostate cancer cell line and compared with these determined for free p-THPP. It was demonstrated that both encapsulation in liposomes as well as attachment of PEG chain result in pronounced reduction of the dark cytotoxicity of the parent porphyrin. The liposomal formulation showed higher than p-THPP–PEG2000 photocytotoxicity towards both cell lines used in the studies. 相似文献