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1.
Minerva Urol Nefrol ; 60(1): 65-7, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18427437

RESUMEN

Lymphangioma is a rare benign tumor caused by failure in the development of the lymphatic communicating system. The corresponding nomenclature is confusing. In recent years ''renal lymphangiectasia'' is the preferred name. Although this disease may occur in any site of the body, the neck (75%) and axillary area (20%) are the most common sites, and the kidney is occasionally involved. We report a case of lymphangioma communicating with the urinary system in a 61-year-old man diagnosed by CT scan treated with nephrectomy and histological confirmation.


Asunto(s)
Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/cirugía , Linfangioma/diagnóstico por imagen , Linfangioma/cirugía , Humanos , Masculino , Persona de Mediana Edad , Nefrectomía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
2.
Eur J Ophthalmol ; 17(2): 230-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17415697

RESUMEN

PURPOSE: To investigate the 6-month safety and clinical outcomes of intravitreal injections of bevacizumab administered to treat choroidal neovascularization secondary to age-related macular degeneration. METHODS: Twenty-seven patients underwent 1.25 mg intravitreal injections of bevacizumab at baseline. A similar intravitreal injection was administered to all eyes at 1 and 2 month follow-up visits. At baseline and at each follow-up visit (1, 2, 3, and 6 months), patients underwent best-corrected visual acuity (BCVA) measurement, fluorescein angiography, indocyanine green angiography, and optical coherence tomography. Laboratory testing, visual field analyses, and endothelial cell counts were performed at baseline and third and sixth months. RESULTS: At 3 months, the mean BCVA remained substantially stable at 20/100. Mean central retinal thickness (CRT) decreased from 373 to 279 microm (p<0.01). Mean lesion greatest linear dimension (GLD) decreased from 4087 to 3782 microns (p<0.01). At 6 months, mean BCVA slightly decreased from 20/100(-1) to 20/125(-3) (not significant, p=0.40). Mean CRT was still inferior to baseline (305 microm, p<0.01). Mean lesion GLD was 4186 microm, not different from baseline values (p=0.59), but superior to 3-month mean GLD (p<0.01). Significant visual field defects or endothelial cell losses were not detected at 3 and 6 months. Laboratory testing did not reveal any clinically significant deviations compared to baseline values. CONCLUSIONS: Intravitreal therapy using bevacizumab over 6 months showed stabilization of visual acuity and choroidal neovascularization activity; the safety data were convincing.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Neovascularización Coroidal/tratamiento farmacológico , Degeneración Macular/complicaciones , Anciano , Anciano de 80 o más Años , Inhibidores de la Angiogénesis/efectos adversos , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados , Bevacizumab , Recuento de Células , Neovascularización Coroidal/diagnóstico , Neovascularización Coroidal/etiología , Colorantes , Femenino , Angiografía con Fluoresceína , Estudios de Seguimiento , Humanos , Verde de Indocianina , Inyecciones , Masculino , Estudios Prospectivos , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Agudeza Visual , Campos Visuales , Cuerpo Vítreo
3.
Hernia ; 9(3): 291-3, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15611836

RESUMEN

Ureteral hernia is uncommon and usually misdiagnosed. From an anatomic point of view, we can distinguish between two uretero-inguinal hernias: intraperitoneal and extraperitoneal. Ureter inguinal hernias are nearly always indirect. This kind of hernia can include the ureter alone or, frequently, other abdominal sliding organs within the hernia sac (bladder, bowel tracts, etc.). Kidneys and urinary tracts present normal anatomic conformation, although renal ptosis may be found. As of July 2004, 139 cases of ureteral hernia had been described in the literature. Here we report a case of inguino-scrotal herniation of double district ureter and review the current literature to analyze the main clinical characteristics of this pathology and to establish pitfalls.


Asunto(s)
Hernia Inguinal/patología , Escroto/patología , Uréter/patología , Diabetes Mellitus Tipo 2/complicaciones , Hernia Inguinal/complicaciones , Hernia Inguinal/cirugía , Humanos , Masculino , Persona de Mediana Edad , Obesidad Mórbida/complicaciones , Uréter/anomalías
4.
Cancer Epidemiol Biomarkers Prev ; 7(4): 341-6, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9568791

RESUMEN

We conducted a case-control study on 114 bladder cancer patients and 46 hospital controls. DNA adducts were measured in WBCs by 32P postlabeling and showed no association with smoking habits and the glutathione-S-transferase M1 genotype. A strong association between adduct levels and the N-acetyltransferase (NAT2) genotype was found (P = 0.0002). The NAT2 genotype was associated in a nonstatistically significant way to the case-control status (odds ratio, 1.6; 95% confidence interval, 0.8-3.2). In a logistic regression model, the log of DNA adduct levels was associated in a highly significant way to the risk of bladder cancer (regression coefficient, 0.75; P = 0.0006), independently of smoking habits. Using the median of DNA adducts (RAL, 0.3) as a cutoff point, the odds ratio for the risk of bladder cancer was 4.1 (age-adjusted; 95% confidence interval, 1.9-9.0). Our study suggests that sources other than tobacco smoke contribute to the formation of aromatic DNA adducts in WBCs. The role of WBC-DNA adducts in predicting bladder cancer is still to be clarified.


Asunto(s)
Arilamina N-Acetiltransferasa/genética , Aductos de ADN/sangre , Glutatión Transferasa/genética , Leucocitos/química , Fumar/efectos adversos , Neoplasias de la Vejiga Urinaria/sangre , Neoplasias de la Vejiga Urinaria/genética , Adulto , Anciano , Estudios de Casos y Controles , Genotipo , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Neoplasias de la Vejiga Urinaria/enzimología
5.
Phys Rev Lett ; 85(22): 4652-5, 2000 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-11082619

RESUMEN

A novel kind of aperiodic stochastic resonance is experimentally studied in a vertical cavity surface emitting laser. We characterize the response of the system to a random, binary signal as a function of an applied external noise. A maximum in the input-output correlation is found for a nonzero added noise. We present analytic results with a good agreement with the measurements. We also discuss the physical meaning of the phenomenon using simple arguments, and we compare it to stochastic resonance.

6.
Phys Rev Lett ; 84(15): 3298-301, 2000 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-11019074

RESUMEN

Experimental evidence of coherence resonance in an optical system is reported. We show that the regularity of the excitable pulses in the intensity of a laser diode with optical feedback increases when adding noise, up to an optimal value of the noise strength. Both phase and amplitude fluctuations of the pulses play a relevant role in the dynamics of the system. We introduce the joint entropy of the two variables to generalize the indicator of coherence, and we put in evidence the mechanism of destruction of the excitable orbit after the resonance.

7.
Phys Rev Lett ; 85(17): 3616-9, 2000 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-11030964

RESUMEN

We conjecture that in one-dimensional spatially extended systems the propagation velocity of correlations coincides with a zero of the convective Lyapunov spectrum. This conjecture is successfully tested in three different contexts: (i) a Hamiltonian system (a Fermi-Pasta-Ulam chain of oscillators); (ii) a general model for spatiotemporal chaos (the complex Ginzburg-Landau equation); (iii) experimental data taken from a CO2 laser with delayed feedback. In the last case, the convective Lyapunov exponent is determined directly from the experimental data.

8.
Org Lett ; 3(19): 3041-3, 2001 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-11554838

RESUMEN

Efficient oxidation of primary alcohols and beta-amino alcohols to the corresponding aldehydes and alpha-amino aldehydes can be carried out at room temperature and in methylene chloride, using trichloroisocyanuric acid in the presence of catalytic TEMPO: aliphatic, benzylic, and allylic alcohols, and beta-amino alcohols are rapidly oxidized without no overoxidation to carboxylic acids. Secondary carbinols are slowly oxidized so that the reaction is highly chemoselective. Reaction: see text.

9.
Org Lett ; 3(10): 1519-21, 2001 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-11388856

RESUMEN

[reaction: see text] Carboxylic acids and amino acids are readily converted, under mild conditions, into the corresponding activated esters, which are reacted with Grignard/CuI reagent to give the corresponding ketones in nearly quantitative yields. The compounds were recovered substantially pure from the reaction mixtures.

10.
Org Lett ; 3(6): 855-7, 2001 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-11263899

RESUMEN

A new polymer-supported radical source was developed by loading an N-hydroxy thiazole 2(3)-thione on a Wang resin. This new supported reagent can be employed for a solid-phase version of the Hunsdiecker reaction or to liberate free alkoxy radicals, in a variant of the "catch and release" technique, under very mild conditions (irradiation with a discharge lamp) and simplifying the purification procedure.

11.
Health Serv Res ; 26(3): 325-37, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1869443

RESUMEN

Knowledge of how cesarean birth rates vary by hospital characteristics may aid in understanding and perhaps modifying some of the structural and process components of newborn delivery services to decrease the necessity of birth by cesarean procedure. To examine the influence of select hospital characteristics, data on hospital newborn deliveries in Illinois for 1986 among women 10-50 years of age inclusive (N = 130,249) were obtained from computerized hospital discharge abstract files. Characteristics of the hospitals were obtained from the annual American Hospital Association survey. Adjusting for mother's age at delivery; presence of pregnancy, labor, and delivery complications; expected primary payer; and size of hospital, women delivering in hospitals with teaching status were less likely (odds ratio = 0.76, p less than .001, 95 percent CL: 0.73, 0.79) to have a primary cesarean birth than women delivering in hospitals without this designation. A significantly lower cesarean birth rate in teaching hospitals was also observed in women of all age groups, in Medicaid and non-Medicaid women, and for most categories of delivery complications. These data suggest the need to identify the programmatic, technologic, and manpower functions associated with hospital teaching status that could decrease the likelihood of a primary cesarean delivery. The study also suggests that changes aimed at the manner of diagnosis, monitoring, and/or management of pregnancy/delivery complications may reduce the cesarean birth rate because of large differences in the primary cesarean birth rate found between teaching and other hospitals for most categories of newborn delivery complications.


Asunto(s)
Cesárea/estadística & datos numéricos , Hospitales/clasificación , Adolescente , Adulto , Niño , Protocolos Clínicos , Recolección de Datos , Distocia/complicaciones , Femenino , Sufrimiento Fetal/complicaciones , Capacidad de Camas en Hospitales , Hospitales de Enseñanza/estadística & datos numéricos , Humanos , Illinois , Recién Nacido , Edad Materna , Persona de Mediana Edad , Complicaciones del Trabajo de Parto/cirugía , Embarazo
12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 63(5 Pt 1): 051110, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11414890

RESUMEN

We study the response of a bistable vertical cavity surface emitting laser to an aperiodic binary signal, by adding a variable amount of noise. The resulting behavior is an example of aperiodic stochastic resonance, and in this work we give a detailed comparison between analytical and numerical results and accurate experimental measurements. We characterize the phenomenon by using different appropriate indicators, which also allow us to quantify the binary information transmission. We show that the quality of the transmission is enhanced by a suitable amount of noise, and we give a physical picture of the phenomenon.

13.
Adv Space Res ; 18(4-5): 101-12, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-11538786

RESUMEN

Information acquisition is the foremost requirement for the control and continued operation of any complex system. This is especially true when a plant production system is used as a major component in a sustainable life support system. The plant production system not only provides food and fiber but is a means of providing critically needed life supporting elements such as O2 and purified H2O. The success of the plant production system relies on close monitoring and control of the production system. Machine vision technology was evaluated for the monitoring of plant health and development and showed promising results. Spectral and morphological characteristics of a model plant were studied under various artificially induced stress conditions. From the spectroscopic studies, it was found that the stresses can be determined from visual and non-visual symptoms. The development of the plant can also be quantified using a video image analysis base approach. The correlations between the qualities of the model plant and machine vision measured spectral features were established. The success of the research has shown a great potential in building an automated, closed-loop plant production system in controlled environments.


Asunto(s)
Sistemas Ecológicos Cerrados , Ambiente Controlado , Monitoreo del Ambiente/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Lactuca/crecimiento & desarrollo , Sistemas de Manutención de la Vida/instrumentación , Monitoreo del Ambiente/instrumentación , Sistemas Especialistas , Lactuca/química , Fotograbar , Desarrollo de la Planta , Hojas de la Planta/química , Hojas de la Planta/fisiología , Espectrofotometría/métodos , Integración de Sistemas , Agua/análisis
14.
Adv Space Res ; 18(1-2): 175-80, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-11538960

RESUMEN

This is an overview of research activities in the areas of flexible automation and robotics (FAR) within controlled environment plant production systems (CEPPS) in the Department of Bioresource Engineering, Rutgers University. In the past thirty years, our CEPPS research has dealt with the topics including structures and energy, environmental monitoring and control, plant growing systems, operations research and decision support systems, flexible automation and robotics, and impact to natural (i.e. surrounding) environment. Computer and modeling/simulation techniques have been utilized extensively. Mechanized systems have been developed to substitute human's physical labor and maintain uniformity in production. Automation research has been directed towards adding, to the mechanized systems, the capabilities of perception, reasoning, communication, and task planning. Computers, because of their programmability, provide flexibility to automated systems, when incorporated with generic hardware devices. Robots are ideal hardware tools to be employed in flexible automation systems. Some technologies developed in our CEPPS research may be readily adaptable to Closed Bioregenerative Life Support Systems (CBLSS).


Asunto(s)
Inteligencia Artificial , Ambiente Controlado , Robótica , Análisis de Sistemas , Integración de Sistemas , Universidades , Automatización , Solanum lycopersicum/crecimiento & desarrollo , New Jersey , Investigación
15.
Adv Space Res ; 14(11): 191-7, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11540180

RESUMEN

Acquisition and analysis of sensory information are foremost for the control and continued operation of any complex system. The sensors and their attributes must be selected by understanding the biological and physical parameters which, first, can describe, and second, when linked to control systems, can modulate, the plant growth system. These parameters are not all understood, or known, and practical sensors may not even exist for their measurement. A systematic analysis of the general plant system would: focus without prejudice on all the descriptive parameters, as well as, their interrelationships within the biophysical system; highlight the significance of each parameter; expose the areas of weakness and strength of current knowledge; expand the knowledge base; provide the platform for the development of operational models for real-time monitoring and control requirements; and support the longer term tactical and strategic planning needs. Components of such a procedure of systematic analysis which is in development for intensive plant production systems within controlled environments will be discussed.


Asunto(s)
Simulación por Computador , Ambiente Controlado , Hidroponía/métodos , Sistemas de Manutención de la Vida/instrumentación , Desarrollo de la Planta , Análisis de Sistemas , Sistemas Ecológicos Cerrados , Procesamiento Automatizado de Datos , Hidroponía/instrumentación , Procesamiento de Señales Asistido por Computador
16.
Radiat Meas ; 28(1-6): 463-6, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-11541795

RESUMEN

CR-39 nuclear track detectors have been used in this experiment to study the killing effect of low energy protons on V79-753B Chinese hamster cells and to monitor the proton beam. The estimated surviving fractions and the beam parameters are comparable to those found with conventional electronic devices. The surviving fractions fitted by the linear quadratic model support the idea of single-hit mechanism for the cell killing.


Asunto(s)
Células Cultivadas/efectos de la radiación , Protones , Monitoreo de Radiación/instrumentación , Animales , Supervivencia Celular/efectos de la radiación , Cricetinae , Cricetulus , Relación Dosis-Respuesta en la Radiación , Transferencia Lineal de Energía , Aceleradores de Partículas , Plásticos , Polietilenglicoles , Dosis de Radiación , Efectividad Biológica Relativa , Temperatura
17.
Health Phys ; 58(3): 329-39, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2312297

RESUMEN

Strontium-90 is of relevant biological importance among fission products released during a fission reactor accident. Rapid information on its concentration in environmental matrices is extremely valuable, yet this implies chemical separations and handling with a shift in daughter equilibrium and therefore the need to wait a sufficient time for the equilibrium to be reestablished. The work concerns a feasibility study of a multi-detector system for a prompt evaluation of the 90Sr activity or, at least, a prompt determination of its order of magnitude in the presence of other pure beta and beta-gamma emitters; their interferences are examined on the basis of the Chernobyl releases and their decay properties. The technique is based on a plastic scintillator beta detector and a guard ring of BGO counters which can be logically connected in coincidence and anticoincidence. The evaluations show that a few hours are sufficient to determine a specific activity comparable with the Maximum Permissible Concentration in air by sampling 10 m3.


Asunto(s)
Accidentes , Contaminantes Ambientales/análisis , Reactores Nucleares , Monitoreo de Radiación/instrumentación , Radioisótopos de Estroncio/análisis , Monitoreo de Radiación/métodos
18.
Health Phys ; 72(4): 629-32, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9119689

RESUMEN

Systematic radon monitoring in the Gran Sasso Underground Laboratory was performed in order to determine the background radon contribution to the sophisticated experimental apparatus and to check health physics standards for the personnel. As expected, the radon concentrations were found to depend strongly on the ventilation in the three experimental halls. Considerable reductions in the radon concentrations were obtained in 1993, when fresh air was drawn into the laboratory through a pipe and exhaust air was routed into the highway tunnel.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , Radón/análisis , Contaminación del Aire Interior/prevención & control , Humanos , Italia , Laboratorios , Exposición Profesional , Ventilación
19.
Trans ASAE ; 46(2): 531-8, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14552353

RESUMEN

The SUBSTOR crop growth model was adapted for controlled-environment hydroponic production of potato (Solanum tuberosum L. cv. Norland) under elevated atmospheric carbon dioxide concentration. Adaptations included adjustment of input files to account for cultural differences between the field and controlled environments, calibration of genetic coefficients, and adjustment of crop parameters including radiation use efficiency. Source code modifications were also performed to account for the absorption of light reflected from the surface below the crop canopy, an increased leaf senescence rate, a carbon (mass) balance to the model, and to modify the response of crop growth rate to elevated atmospheric carbon dioxide concentration. Adaptations were primarily based on growth and phenological data obtained from growth chamber experiments at Rutgers University (New Brunswick, N.J.) and from the modeling literature. Modified-SUBSTOR predictions were compared with data from Kennedy Space Center's Biomass Production Chamber for verification. Results show that, with further development, modified-SUBSTOR will be a useful tool for analysis and optimization of potato growth in controlled environments.


Asunto(s)
Dióxido de Carbono/farmacología , Ambiente Controlado , Hidroponía , Modelos Biológicos , Solanum tuberosum/crecimiento & desarrollo , Biomasa , Simulación por Computador , Sistemas Ecológicos Cerrados , Sistemas de Manutención de la Vida , Luz , Fotosíntesis , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/efectos de la radiación , Solanum tuberosum/efectos de los fármacos , Solanum tuberosum/efectos de la radiación
20.
Minerva Stomatol ; 53(10): 543-54, 2004 Oct.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-15531870

RESUMEN

AIM: Techniques based on NiTi engine driven files for shaping and warm gutta percha for obturing the root canal space are becoming more and more popular. Aim of this paper is to evaluate, by a clinical longitudinal study, the type of sealing and the outcome of endodontic treatment, performed by new Profile and Thermafil technique, in teeth with or without periapical lesions. METHODS: A total of 122 teeth in 64 patients were consecutively enrolled in the study; 63 teeth had normal periapical status (Group A) and 59 teeth had periapical lesion (Group B). Endodontic therapy was carried out by Profile .04 and Profile .06 NiTi engine driven files and the obturation was made by Thermafil, a filling technique based on heated gutta-percha surrounding a plastic carrier. The type of sealing was evaluated by a score (A best - D worst) and the type of healing was classified as complete, incomplete and failure according to previous published data. The radiographical outcome of the teeth was evaluated by independent observers after 24 months. Data were analysed by non parametric statistics. RESULTS: At the end of the study, 115 teeth (59 group A and 56 group B) were examined. The quality of sealing was evaluated and some differences were reported comparing different types of teeth. The radiographic outcome was evaluated and 94.9% showed to be completely healed in group A and 48.2% in group B (p=0.0001). CONCLUSION: The technique based on NiTi engine driven files and Thermafil heated gutta-percha has shown, after 24 months, results which were comparable to other root canal shaping and filling methods.


Asunto(s)
Tratamiento del Conducto Radicular/instrumentación , Tratamiento del Conducto Radicular/métodos , Adulto , Femenino , Encuestas de Atención de la Salud , Humanos , Estudios Longitudinales , Masculino , Estudios Prospectivos , Factores de Tiempo
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