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61.
Results are reported on the cellular effects and the sensitivity of cultured tumor epithelial cells (TEC) derived from human ovarian cystadenocarcinoma and human umbilical vein-derived endothelial cells (HUVEC) to exogenous 5-aminolaevulinic acid (ALA) and ALA-induced photodynamic therapy (PDT). Cellular alterations and PDT efficiency were evaluated using colorimetric thiazolyl blue (MTT) assay, trypan blue exclusion assay, electron microscopy, and gel electrophoresis. ALA-induced protoporphyrin IX (PpIX) accumulation in TEC was associated with a concentration and time-dependent significant decrease in mitochondrial activity, increase in cell membrane permeability, and dark toxicity. Maximum PpIX loaded TEC demonstrated a high sensitivity to PDT. Neither cellular alterations nor PDT effects were observed in HUVEC under identical experimental conditions. These results indicate a potential clinical value for the use of ALA-mediated PDT to treat minimal residual disease in mucinous ovarian carcinoma. In addition, the ALA-induced PpIX cytotoxicity may be exported to a new chemotherapeutic regimen via a conventionally viewed photochemotherapeutic agent.  相似文献   
62.
The excess molar volumes VE for binary liquid mixtures containing dipropylene glycol monomethyl ether and methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, and 1-heptanol have been measured using a continuous dilution dilatometer over the whole mole fraction range at 25°C at atmospheric pressure. VE are negative over the whole composition range except for the systems containing 1-pentanol, 1-hexanol, or 1-heptanol which are positve at every composition. VE increases in a positive direction with increase in chain length of the n-alcohol. The results have been used to estimate the excess partial molar volumes ViE of the components. The change of VE and ViE with composition and the number of carbon atoms in the alcohol molecule are discussed as a basis to understand some of the molecular interactions present in the mixtures:  相似文献   
63.
Periodontal diseases like gingivitis and periodontitis are primarily caused by dental plaque. Several antiplaque and anti-microbial agents have been successfully incorporated into toothpastes and mouthwashes to control plaque biofilms and to prevent and treat gingivitis and periodontitis. The aim of this article was to review recent developments in the antiplaque, anti-gingivitis, and anti-periodontitis properties of some common compounds in toothpastes and mouthwashes by evaluating basic and clinical studies, especially the ones published in the past five years. The common active ingredients in toothpastes and mouthwashes included in this review are chlorhexidine, cetylpyridinium chloride, sodium fluoride, stannous fluoride, stannous chloride, zinc oxide, zinc chloride, and two herbs—licorice and curcumin. We believe this comprehensive review will provide useful up-to-date information for dental care professionals and the general public regarding the major oral care products on the market that are in daily use.  相似文献   
64.
The paper presents a classification of all homogeneous (integrable) complex structures on compact, connected lie groups of even dimension. Thereafter, using lie algebraic methods it proves theorems about the Dolbeault cohomology rings of these complex manifolds in the semisimple case and exhibits the dramatic variation of ring structure of the Dolbeault rings of groups of rank 2. Using some specific computations forSO(9), it gives a counter-example to a long-standing conjecture about the Hodge-deRham (Frohlicher) spectral sequence.  相似文献   
65.
We consider ternary matrices, i.e., integer matrices having all entries 0, 1 or 2. Three associated problems—the group problem, covering, and packing—are studied. General classes of vertices and facets are discussed in each case. Certain lifting procedures are also described. For all three problems techniques used are natural extensions of those used in the binary case.  相似文献   
66.
60 display transport properties vastly different from their unpolymerized counterparts. We here describe structural (X-ray diffraction and transmission electron microscopy) and dc resistivity measurements of polymerized AC60 (A = K, Rb) at zero and high pressures. The structural and electronic properties are rich, and evidence is found for unusual phase transitions in both materials. Received: 28 October 1996/Accepted: 13 December 1996  相似文献   
67.
68.
Ultrasound-promoted synthesis of 2,3-dihydro-4(1H)-quinazolinones and 1-amidoalkyl-2-naphthols were carried out using magnetic nanoparticle-immobilized ionic liquid (IL@MNP) as a magnetically separable catalyst. Ultrasound accelerates the reaction at ambient temperature making the protocol clean, simple and greener compared to conventional procedures. The catalyst showed high activity and stability during the reaction. The heterogeneous nature of the catalyst enabled easy recovery through an external magnet and it was reused up to six times without the loss of its activity. The synergistic effect of IL@MNP and ultrasound facilitate the reaction with excellent isolated yield in a shorter reaction time.  相似文献   
69.
Among dissociation methods, negative electron transfer dissociation (NETD) has been proven the most useful for glycosaminoglycan (GAG) sequencing because it produces informative fragmentation, a low degree of sulfate losses, high sensitivity, and translatability to multiple instrument types. The challenge, however, is to distinguish positional sulfation. In particular, NETD has been reported to fail to differentiate 4-O- versus 6-O-sulfation in chondroitin sulfate decasaccharide. This raised the concern of whether NETD is able to differentiate the rare 3-O-sulfation from predominant 6-O-sulfation in heparan sulfate (HS) oligosaccharides. Here, we report that NETD generates highly informative spectra that differentiate sites of O-sulfation on glucosamine residues, enabling structural characterizations of synthetic HS isomers containing 3-O-sulfation. Further, lyase-resistant 3-O-sulfated tetrasaccharides from natural sources were successfully sequenced. Notably, for all of the oligosaccharides in this study, the successful sequencing is based on NETD tandem mass spectra of commonly observed deprotonated precursor ions without derivatization or metal cation adduction, simplifying the experimental workflow and data interpretation. These results demonstrate the potential of NETD as a sensitive analytical tool for detailed, high-throughput structural analysis of highly sulfated GAGs.
Graphical Abstract
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70.
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