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1.
World J Urol ; 42(1): 234, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38613692

RESUMEN

PURPOSE: We aimed to accurately determine ureteral stricture (US) rates following urolithiasis treatments and their related risk factors. METHODS: We conducted a systematic review and meta-analysis following the PRISMA guidelines using databases from inception to November 2023. Studies were deemed eligible for analysis if they included ≥ 18 years old patients with urinary lithiasis (Patients) who were subjected to endoscopic treatment (Intervention) with ureteroscopy (URS), percutaneous nephrolithotomy (PCNL), or shock wave lithotripsy (SWL) (Comparator) to assess the incidence of US (Outcome) in prospective and retrospective studies (Study design). RESULTS: A total of 43 studies were included. The pooled US rate was 1.3% post-SWL and 2.1% post-PCNL. The pooled rate of US post-URS was 1.9% but raised to 2.7% considering the last five years' studies and 4.9% if the stone was impacted. Moreover, the pooled US rate differed if follow-ups were under or over six months. Patients with proximal ureteral stone, preoperative hydronephrosis, intraoperative ureteral perforation, and impacted stones showed higher US risk post-endoscopic intervention with odds ratio of 1.6 (P = 0.05), 2.6 (P = 0.009), 7.1 (P < 0.001), and 7.47 (P = 0.003), respectively. CONCLUSIONS: The overall US rate ranges from 0.3 to 4.9%, with an increasing trend in the last few years. It is influenced by type of treatment, stone location and impaction, preoperative hydronephrosis and intraoperative perforation. Future standardized reporting and prospective and more extended follow-up studies might contribute to a better understanding of US risks related to calculi treatment.


Asunto(s)
Hidronefrosis , Cálculos Ureterales , Urolitiasis , Humanos , Adolescente , Constricción Patológica , Estudios Prospectivos , Estudios Retrospectivos , Urolitiasis/cirugía , Ureteroscopía/efectos adversos , Cálculos Ureterales/cirugía
2.
Vet Rec ; 181(17): 454-455, 2017 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-29074796

RESUMEN

In a review summary on page 450, Pasmans and others discuss the future of keeping reptiles and amphibians as pets. Here, Clifford Warwick and others discuss the animal welfare and public health implications of exotic pet business.


Asunto(s)
Anfibios , Bienestar del Animal , Animales Exóticos , Salud Pública , Reptiles , Animales , Comercio , Predicción
3.
Br J Anaesth ; 119(5): 964-971, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28981572

RESUMEN

BACKGROUND: Spinal Anaesthesia (SA) has been firmly established as an efficient and safe technique, with minimal cardio-respiratory disturbance when administered in the neonatal period. Our objective was to assess the haemodynamic consequences of SA in infants, particularly its impact on cerebral perfusion using near-infrared spectroscopy (NIRS)-based cerebral oximetry (rSco2). METHODS: All infants up to 60 weeks' postmenstrual age, whether formerly preterm or not, and undergoing spinal anaesthesia, were enrolled. Haemodynamic data records, rSco2 and mean arterial blood pressure (MAP), were prospectively collected before SA (T0) and every five min for 30 min (T30) after the puncture. Compared with baseline measures, any changes of > 10% in rSco2 and of > 20% in MAP were considered clinically significant. Relative variations of data between T0 and T30 were analysed. RESULTS: Data of 103 infants were analysed. The mean relative changes in rSco2 were -2.25% (97.5% CI [-3.97; -0.5]) at T15, and 0.11% (97.5% CI [-1.67; 1.90]) at T30. No significant variation of rSco2 was recorded. The mean changes in MAP were respectively -13.94% (97.5% CI [-17.74; -10.14]) at T15 and -20.27% (97.5% CI [-24,25; -16.29]) at T30. MAP decrease was statistically and clinically significant 30 min after SA. No correlation between changes in MAP and rSco2 was found. The subgroup analysis did not reveal any effect of added intrathecal clonidine or preterm birth history on these results. CONCLUSIONS: In neonate and infants, SA did not cause clinically significant variation in cerebral oxygen saturation. Despite a significant decrease in MAP, cerebral auto-regulation seems to remain effective in neonates and not altered by spinal anaesthesia.


Asunto(s)
Anestesia Raquidea , Encéfalo/irrigación sanguínea , Encéfalo/efectos de los fármacos , Circulación Cerebrovascular/efectos de los fármacos , Encéfalo/fisiología , Circulación Cerebrovascular/fisiología , Femenino , Hemodinámica/fisiología , Humanos , Lactante , Recién Nacido , Masculino , Oximetría/métodos , Estudios Prospectivos , Espectroscopía Infrarroja Corta
4.
J Neural Transm (Vienna) ; 123(7): 737-750, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27194228

RESUMEN

The use of robotics in neurosurgery and, particularly, in stereotactic neurosurgery, is becoming more and more adopted because of the great advantages that it offers. Robotic manipulators easily allow to achieve great precision, reliability, and rapidity in the positioning of surgical instruments or devices in the brain. The aim of this work was to experimentally verify a fully automatic "no hands" surgical procedure. The integration of neuroimaging to data for planning the surgery, followed by application of new specific surgical tools, permitted the realization of a fully automated robotic implantation of leads in brain targets. An anthropomorphic commercial manipulator was utilized. In a preliminary phase, a software to plan surgery was developed, and the surgical tools were tested first during a simulation and then on a skull mock-up. In such a way, several tools were developed and tested, and the basis for an innovative surgical procedure arose. The final experimentation was carried out on anesthetized "large white" pigs. The determination of stereotactic parameters for the correct planning to reach the intended target was performed with the same technique currently employed in human stereotactic neurosurgery, and the robotic system revealed to be reliable and precise in reaching the target. The results of this work strengthen the possibility that a neurosurgeon may be substituted by a machine, and may represent the beginning of a new approach in the current clinical practice. Moreover, this possibility may have a great impact not only on stereotactic functional procedures but also on the entire domain of neurosurgery.


Asunto(s)
Encefalopatías/cirugía , Encéfalo/cirugía , Neurocirugia/instrumentación , Neurocirugia/métodos , Robótica , Técnicas Estereotáxicas , Animales , Humanos , Reproducibilidad de los Resultados , Técnicas Estereotáxicas/instrumentación , Porcinos , Terapia Asistida por Computador/instrumentación
5.
Rev Sci Instrum ; 81(8): 083505, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20842778

RESUMEN

In the past years cameras have become increasingly common tools in scientific applications. They are now quite systematically used in magnetic confinement fusion, to the point that infrared imaging is starting to be used systematically for real-time machine protection in major devices. However, in order to guarantee that the control system can always react rapidly in case of critical situations, the time required for the processing of the images must be as predictable as possible. The approach described in this paper combines the new computational paradigm of cellular nonlinear networks (CNNs) with field-programmable gate arrays and has been tested in an application for the detection of hot spots on the plasma facing components in JET. The developed system is able to perform real-time hot spot recognition, by processing the image stream captured by JET wide angle infrared camera, with the guarantee that computational time is constant and deterministic. The statistical results obtained from a quite extensive set of examples show that this solution approximates very well an ad hoc serial software algorithm, with no false or missed alarms and an almost perfect overlapping of alarm intervals. The computational time can be reduced to a millisecond time scale for 8 bit 496560-sized images. Moreover, in our implementation, the computational time, besides being deterministic, is practically independent of the number of iterations performed by the CNN-unlike software CNN implementations.

6.
Rev Laryngol Otol Rhinol (Bord) ; 130(4-5): 289-91, 2009.
Artículo en Francés | MEDLINE | ID: mdl-20597413

RESUMEN

Paranasal sinus mucoceles can present ophthalmic disturbances. Our aim is to discuss the treatment and the endoscopic sinus surgery indication in the fronto-ethmoidal sinus mucoceles. We describe here a case of fronto-ethmoidal sinus mucocele in a patient with an important fronto-ethmoidal tumefaction and an increased prominence of his left eyeball. An endoscopic approach was done after explain to the patient the eventual risks and complications of the procedure, especially to his left eye.


Asunto(s)
Neoplasias Óseas/diagnóstico , Neoplasias Óseas/cirugía , Hueso Etmoides/cirugía , Hueso Frontal/cirugía , Mucocele/diagnóstico , Mucocele/cirugía , Anciano , Diplopía/etiología , Endoscopía , Humanos , Masculino
7.
Nanotechnology ; 17(4): S54-63, 2006 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-21727354

RESUMEN

A new approach to the observation and analysis of dynamic structural and functional parameters in the microcirculation is described. The new non-invasive optical system is based on cellular nonlinear networks (CNNs), highly integrated analogue processor arrays whose processing elements, the cells, interact directly within a finite local neighbourhood. CNNs, thanks to their parallel processing feature and spatially distributed structure, are widely used to solve high-speed image processing and recognition problems and in the description and modelling of biological dynamics through the solution of time continuous partial differential equations (PDEs). They are therefore considered extremely suitable for spatial-temporal dynamic characterization of fluidic phenomena at micrometric to nanometric scales, such as blood flow in microvessels and its interaction with the cells of the vessel wall. A CNN universal machine (CNN-UM) structure was used to implement, via simulation and hardware (ACE16k), the algorithms to determine the functional capillarity density (FCD) and red blood cell velocity (RBCV) in capillaries obtained by intravital microscopy during in vivo experiments on hamsters. The system exploits the moving particles to distinguish the functional capillaries from the stationary background. This information is used to reconstruct a map and to calculate the velocity of the moving objects.

8.
Rev Laryngol Otol Rhinol (Bord) ; 126(1): 33-6, 2005.
Artículo en Francés | MEDLINE | ID: mdl-16080646

RESUMEN

OBJECTIVE: The authors report a case of persistent stapedial artery in a young man who had a chronic ear infection with focus on the CT scan aspects. A review of the literature is done about this rare anomaly. CONCLUSION: Some CT scan aspects (absence of the spinosum foramina, bony canal from the hypotympanum toward the promontory, enlargement of the 2nd portion of the Fallopian canal) are very likely in favor of this diagnosis and allow a preoparative suspicion. If necessary a more complete imaging check up could be performed for searching other malformations.


Asunto(s)
Otitis Media/diagnóstico por imagen , Estribo/irrigación sanguínea , Tomografía Computarizada por Rayos X , Adulto , Arterias/anomalías , Arteria Carótida Interna/anomalías , Enfermedad Crónica , Humanos , Masculino , Otitis Media/cirugía , Timpanoplastia
9.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 2219-22, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-17272167

RESUMEN

A real-time monitoring system based on the dual slit methodology for the characterization of the red blood cell velocity at the level of microcirculation has been developed. The analog photometric signals are acquired and processed using a hybrid hardware-software system that exploits a A/D conversion and an optimized correlation algorithm on an embedded system. It is implemented exploiting the resources of a general purpose board capable to extract the useful information from the noisy photometric signals, to process them, to show and save the results and, therefore, to make the experiments reproducible. Two different approaches to the crosscorrelation algorithm have been tested and their performances have been compared to each. The system has been tested in in vivo experiments on anaesthetized hamsters. Several microvessels have been observed and the results have been compared to the output of an analog crosscorrelator to verify their coherence.

10.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 2231-4, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-17272170

RESUMEN

In this paper, a real-time measurement system for non-invasive evaluation of oxygen concentration (PO2) at the microcirculation level is developed. The system has been designed by exploiting the phenomenon of fluorescence quenching. The skin of an anaesthetized hamster, injected with porphyrin, is lighted with pulses; the fluorophore reacts with the oxygen in the blood, producing a fluorescence signal, and the value of the fluorescence lifetime is related to the oxygen concentration. This microcirculation-based instrumentation consists of an electro-optical system, a control circuit and signal processing procedure. The system allows the measurement of PO2 in the range of 0-700 (mmHg) with a standard deviation of 4 (mmHg). Several experiments have been performed in order to characterize and test this system.

12.
Health Psychol ; 20(1): 20-32, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11199062

RESUMEN

The authors tested effects of a 10-week group cognitive-behavioral stress management intervention among 100 women newly treated for Stage 0-II breast cancer. The intervention reduced prevalence of moderate depression (which remained relatively stable in the control condition) but did not affect other measures of emotional distress. The intervention also increased participants' reports that having breast cancer had made positive contributions to their lives, and it increased generalized optimism. Both remained significantly elevated at a 3-month follow-up of the intervention. Further analysis revealed that the intervention had its greatest impact on these 2 variables among women who were lowest in optimism at baseline. Discussion centers on the importance of examining positive responses to traumatic events--growth, appreciation of life, shift in priorities, and positive affect-as well as negative responses.


Asunto(s)
Terapia Conductista , Neoplasias de la Mama/psicología , Terapia Cognitivo-Conductual , Trastorno Depresivo/prevención & control , Adulto , Anciano , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/terapia , Trastorno Depresivo/epidemiología , Femenino , Humanos , Acontecimientos que Cambian la Vida , Persona de Mediana Edad , Prevalencia , Estrés Psicológico
13.
Artículo en Inglés | MEDLINE | ID: mdl-11046322

RESUMEN

In this paper, a simple system showing chaotic behavior is introduced. It is based on the well-known concept of cellular neural networks (CNNs), which have already given good results in generating complex dynamics. The peculiarity of the CNN model consists in the fact that it replaces the traditional first-order cell with a noninteger-order one. The introduction of the fractional cell, with a suitable choice of the coupling parameters, leads to the onset of chaos in a simple two-cell system. A theoretical approach, based on the harmonic balance theory, has been used to investigate the existence of chaos. A circuit realization of the proposed fractional two-cell chaotic CNN is reported and the corresponding strange attractor is also shown.

14.
Health Psychol ; 18(2): 159-68, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10194051

RESUMEN

Much work on psychosocial sequelae of breast cancer has been guided by the assumption that body image and partner reaction issues are focal. In a tri-ethnic sample of 223 women treated for early-stage breast cancer within the prior year, the authors assessed a wider range of concerns and relations to well-being. Strongest concerns were recurrence, pain, death, harm from adjuvant treatment, and bills. Body-image concerns were moderate; concern about rejection was minimal. Younger women had stronger sexual and partner-related concerns than older women. Hispanic women had many stronger concerns and more disruption than other women. Life and pain concerns and sexuality concerns contributed uniquely to predicting emotional and psychosexual disruption; life and pain concerns and rejection concerns contributed to predicting social disruption. In sum, adaptation to breast cancer is a process bearing on several aspects of the patient's life space.


Asunto(s)
Adaptación Psicológica , Neoplasias de la Mama/psicología , Etnicidad/psicología , Rol del Enfermo , Ajuste Social , Adulto , Anciano , Anciano de 80 o más Años , Ansiedad/psicología , Imagen Corporal , Neoplasias de la Mama/patología , Comparación Transcultural , Femenino , Identidad de Género , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Calidad de Vida
15.
J Health Psychol ; 4(3): 343-56, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-22021602

RESUMEN

Religious involvement was measured in a sample of 49 lower socio-economic status Hispanic women who were newly diagnosed with early-stage breast cancer. Religious coping and emotional distress were assessed at pre-surgery, post-surgery, and at 3-, 6-, and 12-month follow-ups. Among Catholic women, greater religiosity tended to be associated with more distress throughout the year; among Evangelical women, in contrast, greater religiosity tended to be associated with less distress throughout the year. These correlations were significantly different at two measurement points. Similarly, religious coping tended to have divergent effects in the two groups. Among Catholics, church attendance at 6 months predicted greater distress at 12 months; among Evangelical women, obtaining emotional support from church members at 6 months predicted less distress at 12 months. These various differences are interpreted in terms of differences in the ideologies of the two religious groups.

16.
N Engl J Med ; 338(16): 1089-96, 1998 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-9545356

RESUMEN

BACKGROUND: The cumulative risk of a false positive result from a breast-cancer screening test is unknown. METHODS: We performed a 10-year retrospective cohort study of breast-cancer screening and diagnostic evaluations among 2400 women who were 40 to 69 years old at study entry. Mammograms or clinical breast examinations that were interpreted as indeterminate, aroused a suspicion of cancer, or prompted recommendations for additional workup in women in whom breast cancer was not diagnosed within the next year were considered to be false positive tests. RESULTS: A total of 9762 screening mammograms and 10,905 screening clinical breast examinations were performed, for a median of 4 mammograms and 5 clinical breast examinations per woman over the 10-year period. Of the women who were screened, 23.8 percent had at least one false positive mammogram, 13.4 percent had at least one false positive breast examination, and 31.7 percent had at least one false positive result for either test. The estimated cumulative risk of a false positive result was 49.1 percent (95 percent confidence interval, 40.3 to 64.1 percent) after 10 mammograms and 22.3 percent (95 percent confidence interval, 19.2 to 27.5 percent) after 10 clinical breast examinations. The false positive tests led to 870 outpatient appointments, 539 diagnostic mammograms, 186 ultrasound examinations, 188 biopsies, and 1 hospitalization. We estimate that among women who do not have breast cancer, 18.6 percent (95 percent confidence interval, 9.8 to 41.2 percent) will undergo a biopsy after 10 mammograms, and 6.2 percent (95 percent confidence interval, 3.7 to 11.2 percent) after 10 clinical breast examinations. For every 100 dollars spent for screening, an additional 33 dollars was spent to evaluate the false positive results. CONCLUSIONS: Over 10 years, one third of women screened had an abnormal test result that required additional evaluation, even though no breast cancer was present. Techniques are needed to decrease false positive results while maintaining high sensitivity. Physicians should educate women about the risk of a false positive result from a screening test for breast cancer.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Reacciones Falso Positivas , Mamografía , Examen Físico , Adulto , Anciano , Teorema de Bayes , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/psicología , Estudios de Cohortes , Femenino , Humanos , Mamografía/economía , Mamografía/estadística & datos numéricos , Tamizaje Masivo/economía , Tamizaje Masivo/estadística & datos numéricos , Persona de Mediana Edad , Examen Físico/economía , Examen Físico/estadística & datos numéricos , Estudios Retrospectivos , Riesgo
17.
Neural Netw ; 10(2): 335-342, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12662531

RESUMEN

In this paper a new type of multilayer feedforward neural network is introduced. Such a structure, called hypercomplex multilayer perceptron (HMLP), is developed in quaternion algebra and allows quaternionic input and output signals to be dealt with, requiring a lower number of neurons than the real MLP, thus providing a reduced computational complexity. The structure introduced represents a generalization of the multilayer perceptron in the complex space (CMLP) reported in the literature. The fundamental result reported in the paper is a new density theorem which makes HMLPs universal interpolators of quaternion valued continuous functions. Moreover the proof of the density theorem can be restricted in order to formulate a density theorem in the complex space. Due to the identity between the quaternion and the four-dimensional real space, such a structure is also useful to approximate multidimensional real valued functions with a lower number of real parameters, decreasing the probability of being trapped in local minima during the learning phase. A numerical example is also reported in order to show the efficiency of the proposed structure. Copyright 1997 Elsevier Science Ltd. All Rights Reserved.

18.
Technol Health Care ; 4(4): 393-401, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9042690

RESUMEN

The cerebrospinal fluid (CSF) pressure patterns have been reported as one of the most relevant indexes for the diagnosis and treatment of idiopathic normal-pressure hydrocephalus (INPH). Forty consecutive patients coming from our observations with the classic Hakim's triad underwent continuous CSF pressure monitoring via lumbar puncture for at least 12 hours. Twenty-eight patients were diagnosed as having INPH and underwent CSF shunt. A multi-layer neural network (perceptron) was employed to study the pressure patterns in order to try an alternative classification to the "expert" neurosurgeon one. Differences between expert and neural network classifications were indeed observed. Such differences may depend on the small group studied or on the inadequacy of CFS pressure patterns in correctly individuating those INPH patients who benefit from shunt surgery. The authors think that neural network processing of INPH could add relevant information to select the "responder" patients to surgery: in fact neural networks represent a powerful methodology for aiding the expert to select the proper choice on the basis of "what learnt" by the networks themselves.


Asunto(s)
Presión del Líquido Cefalorraquídeo , Hidrocéfalo Normotenso/diagnóstico , Redes Neurales de la Computación , Líquido Cefalorraquídeo/fisiología , Derivaciones del Líquido Cefalorraquídeo , Humanos , Hidrocéfalo Normotenso/líquido cefalorraquídeo , Hidrocéfalo Normotenso/cirugía , Monitoreo Fisiológico , Evaluación de Resultado en la Atención de Salud , Selección de Paciente
19.
Minerva Ginecol ; 48(11): 475-9, 1996 Nov.
Artículo en Italiano | MEDLINE | ID: mdl-9005374

RESUMEN

The authors monitored a group of pregnant patients who presented fetuses with intrauterine retarded growth syndrome. Only pregnant women who were monitored until the time of birth were included in the study. Patients were divided into three groups depending on the week of gestation in which birth occurred and two subgroups were identified within each group depending on the type of birth. Three perinatal deaths (5%) were recorded in the group of patients at risk, a percentage that is comparable to data reported in the literature, in spite of careful monitoring (flow metric and cardiographic). Cesarian section was resorted to in 86.4% of cases and 67.7% of neonates presented decisively "poor" conditions at birth.


Asunto(s)
Retardo del Crecimiento Fetal/fisiopatología , Femenino , Edad Gestacional , Humanos , Recién Nacido , Embarazo
20.
Int J Neural Syst ; 6(4): 435-46, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8963472

RESUMEN

In this paper the approximation capabilities of different structures of complex feedforward neural networks, reported in the literature, have been theoretically analyzed. In particular a new density theorem for Complex Multilayer Perceptrons with complex valued non-analytical sigmoidal activation functions has been proven. Such a result makes Multilayer Perceptrons with complex valued neurons universal interpolators of continuous complex valued functions. Moreover the approximation properties of superpositions of analytic activation functions have been investigated, proving that such combinations are not dense in the set of continuous complex valued functions. Several numerical examples have also been reported in order to show the advantages introduced by Complex Multilayer Perceptrons in terms of computational complexity with respect to the classical real MLP.


Asunto(s)
Redes Neurales de la Computación , Dinámicas no Lineales
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