ABSTRACT
The interaction of 11-mercaptoundecanoic acid capped gold nanoparticles (MUA-GNPs) with europium ions and aminoacids has been studied by UV-Vis spectrophotometry, fluorescence, confocal fluorescence microscopy, resonance light scattering and TEM. Results demonstrated that hyper-Rayleigh scattering emission occurs upon the addition of lysine to the MUA-GNPs-Eu(III) system, thus providing an inherently sensitive method for lysine determination. The effects of geometrical factors of the gold nanoparticles (aspect ratio, particle size, cluster formation) and the surrounding medium (pH) on this behavior are discussed. The cooperative binding interactions of Eu(3+) and lysine with gold nanoparticles permitted the discrimination of lysine from other amino acids. The probable mechanism for the spectral changes and the enhanced resonance light scattering observed is outlined.
ABSTRACT
The direct monitoring of reaction progress on solid supports by fluorescence spectroscopy is described. An immobilized fluorescent tracer molecule (dansyl chloride) is used to monitor the reaction on OH resins (Argopore Wang, PS Wang, and Argogel Wang), both in batch and in parallel chemistry. Fluorescence measurements were obtained directly on solid phase. The method demonstrated to be a valuable tool for the quantitative determination of resin-bound hydroxyl groups, to study reaction kinetics and for continuously monitoring the progress of the conversion of the hydroxyl resins into the chlorinated ones. The procedure proposed is highly sensitive compared to the traditional ones. The system can be extended to monitor a variety of reactions on solid supports, and in conjunction with a well-established technique such as flow analysis, basic studies on solid-phase become possible.
ABSTRACT
OBJECTIVE: To evaluate six risk factors in a population of low economic level. MATERIAL AND METHOD: 40 asthmatic children were studied, 21 masculine and 19 feminine, with a 9.3 years old half age +/- 3.22 years. A group control is included (22 children) without asthma and without allergic symptoms. RESULTS: I intragroup study. In the control group the tobacco atmosphere overcame the prospective frequency (p < 0.05), circumstance that didn't happen to the group of patient. Intragroup studies. There were not significant differences among the parameters studied in both groups, except for the frequency of family antecedents. CONCLUSIONS: The genetic factor is decisive for the initial asthma. The genotypic studies has found the chromosomic locus that regulate their expression. The environmental factors, particularly the tobacco pre and postnatal, they are decisive in the early precipitation of the beginning of the asthma.
Subject(s)
Asthma/epidemiology , Child , Female , Humans , Male , Risk FactorsABSTRACT
Focal oral epithelial hyperplasia (FOEH), also known as Heck's disease is an unusual condition. We had the possibility to observe and study the disease in a negro patient. This is the first case described in Cuba.
Subject(s)
Mouth Diseases/epidemiology , Adult , Black People , Cuba , Epithelium/pathology , Humans , Hyperplasia , Male , Mouth Diseases/pathology , Mouth Mucosa/pathologyABSTRACT
Con objeto de determinar las ventajas y las desventajas de la aplicacion de anillos de silastico como tecnica de esterilizacion femenina bajo control laparoscopico, se analizaron comparativamente y a futuro los eventos ocurridos en un total de 1,302 intervenciones quirurgicos: 544 casos de electrofulguracion tubaria y 758 casos de aplicacion de anillos de silastico. La tasa de complicaciones globales con ambos procedimientos fue muy similar, predominando los problemas de hemorragia tubarica a consecuencia de la tecnica oclusiva. La aplicacion de anillos de silastico presenta una mayor frecuencia de dolor abdominal en las partes inmediata y mediata del periodo postoperatorio. Durante los primeros seis meses siguientes a la operacion, se encontro en el grupo de electrofulguracion una mayor frecuencia de trastornos menstruales en comparacion con lo encontrado en el grupo de anillos de silastico. Se presentaron tres casos de embarazos por falla del metodo en el grupo de anillos de silastico, lo que contrasta con la ausencia de embarazos en el grupo de electrofulguracion
Subject(s)
Humans , Female , Laparoscopy , Sterilization, Tubal , Postoperative ComplicationsABSTRACT
PIP: The results of a comparative study of 3 techniques for tubal occlusion are presented. These techniques were silastic ring, staple with spring, and electrofulguration. The incidence of operative complications was greater with electrofulguration, mainly tubal bleeding (18.2%). The use of the staple with rings had a very high incidence of operative difficulties (37.6%) due to the misplacement of the staple. During the postoperative period there was abdominal pain, with greater incidence in the group with the silastic ring and staple with spring (47.8%). Gynecologic problems during the late postoperative period were infrequent and unrelated to the sterilization. (author's modified)^ieng
Subject(s)
Postoperative Complications/epidemiology , Sterilization, Tubal/methods , Adult , Double-Blind Method , Electrocoagulation/adverse effects , Female , Humans , Laparoscopy/methods , Mexico , Middle Aged , Prospective Studies , Prostheses and Implants/adverse effects , Sterilization, Tubal/adverse effectsABSTRACT
Se presentan los resultados de un estudio comparativo, de tres tecnicas oclusivas tubaricas bajo control laparoscopico: anillo de silastic, grapa con resorte y electrofulguracion. Se encontro que la frecuencia de complicaciones operatorias fue mas alta con el uso de electrofulguracion, predominando los problemas de hemorragia tubarica (18.2 por ciento). El uso de grapas de resorte presento una frecuencia muy alta de dificultades operatorias (37.6 por ciento) debido a colocaciones defectuosas de las mismas.Durante el periodo postoperatorio inmediato y mediato, se presento dolor abdominal, con mayor frecuencia en el grupo de grapas de resorte y anillos de silastic, predominando en este ultimo (47.8 por ciento). Los problemas ginecologicos durante el periodo postoperatorio tardio fueron escasos y no relacionados con la esterilizacion