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2.
Pediatr Dermatol ; 35(1): 121-125, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29243341

RESUMO

BACKGROUND/OBJECTIVE: To report our observations from a trial of the short-term effectiveness and safety of topical carteolol hydrochloride drops to treat infantile hemangiomas (IHs). METHODS: From October 2012 to September 2015, the study recruited 349 children with superficial IHs. Participants were randomized to two groups: treatment (n = 224 who received 2% carteolol hydrochloride drops administered to the lesion surface twice daily) and observation (n = 125 who did not receive treatment). Therapy duration was 6 months. RESULTS: The mean age at the beginning of treatment was 3.2 months. Treatment responses were categorized as class 1 (total regression), class 2 (partial regression or controlled growth), or class 3 (no response). Of infants receiving carteolol treatment, 10.7% (24 patients) were categorized as class 1, 72.3% (162 patients) as class 2, and 17.0% (38 patients) as class 3. Of infants in the observation group, 5.6% (7 patients) were categorized as class 1, 25.6% (32 patients) as class 2, and 68.8% (86 patients) as class 3. No adverse effects were noted during treatment. CONCLUSION: Carteolol is an effective, safe topical treatment for superficial IHs. Carteolol may be used to treat proliferative superficial IHs, particularly in infants younger than 6 months.


Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Carteolol/administração & dosagem , Hemangioma/tratamento farmacológico , Administração Tópica , Povo Asiático , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Resultado do Tratamento , Conduta Expectante
3.
Carbohydr Res ; 348: 64-8, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22197070

RESUMO

A novel method for determining the degree of deacetylation of chitosan is described. This involves a two-abrupt-change of the refractive index of solutions. Principle of the method is that the sample reacts with excessive acid, and the excessive acid is measured by alkaline titration. The refractive index of an aqueous chitosan solution was monitored and recorded in the course of acid-base titration. This gives a titration curve having two inflexion points and the difference between the two points corresponds to the volume of base required to neutralize the ammonium groups. It was proved that flocculation did not interfere with the measurement. The method is found to be low-cost, precise, and easy to operate for industrial applications. The DD values of three chitosan samples obtained with this new method show good agreement with those yielded from (1)H NMR. Such a mechanism of refractive index monitoring should open up a new application in the field of chitosanolytic enzymes, such as chitosanase, that are important in bioprocesses.


Assuntos
Quitosana/química , Tecnologia de Fibra Óptica/instrumentação , Tecnologia de Fibra Óptica/métodos , Acetilação , Algoritmos , Espectroscopia de Ressonância Magnética , Refratometria/métodos , Titulometria/métodos
4.
Anal Biochem ; 401(1): 144-7, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20175982

RESUMO

We describe a simple and rapid method for determining the critical micelle concentration (CMC) of surfactants from fiber-optic measurements of refractive index. The refractive index of an aqueous surfactant solution was monitored as the surfactant concentration was increased using an automated dispensing system. On reaching the surfactant's CMC value, an abrupt change was observed in the rate of increase of the refractive index with increasing concentration. The measurement system provides rapid semiautomatic data collection and analysis, increasing the precision, sensitivity, and range of applicability of the technique while substantially decreasing the amount of manual intervention required. Measurements of CMC for sodium dodecyl sulfate (8.10mM), cetyltrimethylammonium chloride (1.58mM), and Triton X-100 (0.21mM) were in excellent agreement with values previously reported in the literature. The method is applicable to cationic, anionic, and nonionic surfactants, and it offers a facile, in situ, and sensitive means of detecting micelle formation over a broad range of CMC values larger than 10(-1)mM.


Assuntos
Micelas , Refratometria/métodos , Tensoativos/química , Água/química , Cetrimônio , Compostos de Cetrimônio/análise , Octoxinol/análise , Dodecilsulfato de Sódio/análise , Tensoativos/análise
5.
J Autom Methods Manag Chem ; 2009: 101679, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19746179

RESUMO

A flow injection method has been developed for the direct determination of free available Pb(II). The method is based on the chemical sorption of Pb(II), from pH7 solutions, on a column packed of chelating resin. The retained complex was afterwards eluted with hydrochloric acid followed by hydride generation with reduction by tetrahydroborate. The preconcentration system proposed in this paper allows the elimination of great part of the saline content in the sample. A thorough scrutiny was made for chemical variables and FI parameters. With a sampling volume of 10.5 mL, quantitative retention of Pb (II) was obtained, along with an enrichment factor of 40 and a sampling frequency of 15 h(-1). The detection limit, defined as 3 times the blank standard deviation (3sigma), was 0.0031 ngml(-1). The precision was characterized by an RSD value of 3.78% (at the 4 ng.ml(-1) level, n = 11). The developed method has been applied to the determination of trace Pb in three standard reference materials. Accuracy was assessed through comparing the results with the accepted values.

6.
Rev Sci Instrum ; 80(3): 034103, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19334936

RESUMO

A novel fiber sensor for measuring solid solubilities of salt-water systems in situ is described. The sensor consists of a diode laser as light source, three couplers, two sensing fiber ends with protective cladding, and two photodetectors. The measurement principle is based on relative Fresnel reflective intensity. This method enabled us to observe in situ transitional process of the equilibration of a solid-liquid system with a small quantity of specimens. By the relatively simple technique, fast determination of the solid solubility is possible. We applied this method to measure a temperature dependence of the solubility of potassium chloride in water in situ and compared with the previous data obtained by other techniques. The measured result has the long-term standard deviation of the concentration of 0.1%, and agrees with the data obtained by the classical method within the error of +/-1%. This method is precise and sample saving and is suitable to measure the solubilities of rare and expensive materials.

7.
Opt Express ; 16(6): 3680-5, 2008 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-18542462

RESUMO

A novel light-emitting diode (LED) packaging method, named the active packaging (AP) method, is presented in this paper. In this method, during the LED packaging process, the light emitted from a GaN LED chip itself is employed to package the LED encapsulant, thereby eliminating the need to utilize a mold. Current injection into a bare LED chip, triggers a photosensitive epoxy to polymerize, leading to the formation of mushroom lamp cap on the LED chip. The emission properties of LEDs fabricated by this method, including their emission beam profiles and light outputs, were characterized. The results showed that a self-focusing effect happened with the addition of an epoxy on the chip. The simulation demonstrated that the geometry the encapsulant controlled the beam pattern of emission. Further, the self-focusing effect was believed to be caused by the combination of the threshold energy of epoxy polymerization, the beam pattern and the power output of the LED chip.


Assuntos
Cor , Lentes , Iluminação/instrumentação , Fotoquímica/métodos , Polímeros/química , Semicondutores , Desenho de Equipamento , Análise de Falha de Equipamento
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(12): 2763-7, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19248478

RESUMO

The key problem of fabricating the 3-D InP inverse opal photonic crystal is to increase the loading of InP in opals. In the present paper, low-pressure metal-organic chemical-vapour deposition (MOCVD) was used to infill the voids within synthetic opals with InP. The morphologies and optical properties of SiO2-InP photonic crystal were characterized by scanning electron microscopy and ultraviolet-visible spectrophotometry (UV-Vis). Several series of experiments were carried out in order to analyze the factors that influence the loading of InP in opals and determine the optimal InP growth conditions. The results of optical experiments are in good agreement with those derived from the theoretical considerations: By increasing the extent of InP infilling within the voids, the extent of refractive index contrast between the silica spheres and the void as well as the extent of natural optical properties change of the photonic crystal were increased. Cycle growth, low-pressure growth, and using the match substrate and the same configuration character between SiOi and InP are beneficial to increaseing the extent of InP infilling within the opal voids. The process has been optimized to achieve SiO2-InP photonic crystal with higher loading of InP. The study provides a scientific basis for manufacturing three-dimensional InP inverse opal photonic crystals.

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