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1.
Philos Trans A Math Phys Eng Sci ; 377(2142): 20180152, 2019 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-30967036

RESUMEN

The extreme scaling pattern of the ComPat project is applied to a multi-scale workflow relevant to the magnetically confined fusion problem. This workflow combines transport, turbulence and equilibrium codes (together with additional auxiliaries such as initial conditions and numerical module), which aims at calculating the behaviour of a fusion plasma on long (transport) time scales based on information from much faster (turbulence) time scales. Initial findings of profile measurements are reported in this paper and indicate that, depending on the chosen performance metric for defining 'cost', such as time to completion, efficiency and total energy consumption of the mutliscale workflow, different choices on the number of cores would be made when determining the optimal execution configuration. A variant of the workflow which increases the inherent parallelism is presented, and shown to produce equivalent results at (typically) lower cost compared with the original workflow. This article is part of the theme issue 'Multiscale modelling, simulation and computing: from the desktop to the exascale'.

2.
J Viral Hepat ; 25(3): 254-261, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29091323

RESUMEN

Chronic infection with the hepatitis C virus induces liver fibrosis, but it is unknown why some patients progress to advanced fibrosis while others remain with mild disease. Recently, an inverse association between serum levels of dehydroepiandrosterone sulphate (DHEA-S) and liver fibrosis in patients with nonalcoholic fatty liver disease was described, and it was postulated that dehydroepiandrosterone (DHEA) has antifibrotic effects. Our aim was to compare serum DHEA-S levels with liver fibrosis in hepatitis C patients. We collected serum samples from hepatitis C patients at the same day they underwent a liver biopsy. S-DHEA was compared to different stages of fibrosis. Binary logistic regression models were applied to evaluate independent variables associated to fibrosis. We included 287 patients (43.9% male). According to fibrosis stages 0, 1, 2, 3 and 4, median serum DHEA-S levels were 103 (26-462), 73 (5-391), 46 (4-425), 35 (6-292) and 28 (2-115) µg/dL, respectively (P < .001). Median serum DHEA-S levels were 74 (5-462) vs 36 (2-425) µg/dL for mild (F0-1) vs significant (F2-4) fibrosis, respectively (P < .001). Median serum DHEA-S levels were 64 (4-462) vs 31 (2-292) µg/dL for non advanced (F0-2) vs advanced fibrosis (F3-4), respectively (P < .001). The same association was found when the subgroup of HCV patients with and without steatosis or steatohepatitis was analysed. The association between lower DHEA-S levels and advanced fibrosis was independent of age, gender, diabetes mellitus, obesity and steatosis. Lower circulating DHEA-S levels are associated with more advanced stages of liver fibrosis in hepatitis C patients.


Asunto(s)
Sulfato de Deshidroepiandrosterona/sangre , Hepatitis C Crónica/complicaciones , Cirrosis Hepática/patología , Adolescente , Adulto , Anciano , Biopsia , Estudios Transversales , Femenino , Histocitoquímica , Humanos , Hígado/patología , Masculino , Persona de Mediana Edad , Adulto Joven
3.
Int J Sports Med ; 38(8): 604-612, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26667925

RESUMEN

The aim of this study was to test the relationships between jump squat (JS) and Olympic push press (OPP) power outputs and performance in sprint, squat jump (SJ), countermovement jump (CMJ) and change of direction (COD) speed tests in elite soccer players. 27 athletes performed a maximum power load test to determine their bar mean propulsive power (MPP) and bar mean propulsive velocity (MPV) in the JS and OPP exercises. Magnitude-based inference was used to compare the exercises. The MPV was almost certainly higher in the OPP than in the JS. The MPP relative to body mass (MPP REL) was possibly higher in the OPP. Only the JS MPP REL presented very large correlations with linear speed (r>0.7, for speed in 5, 10, 20 and 30 m) and vertical jumping abilities (r>0.8, for SJ and CMJ), and moderate correlation with COD speed (r=0.45). Although significant (except for COD), the associations between OPP outcomes and field-based measurements (speed, SJ and CMJ) were all moderate, ranging from 0.40 to 0.48. In a group composed of elite soccer players, the JS exercise is more associated with jumping and sprinting abilities than the OPP. Longitudinal studies are needed to confirm if these strong relationships imply superior training effects in favor of the JS exercise.


Asunto(s)
Rendimiento Atlético/fisiología , Ejercicio Físico/fisiología , Ejercicio Pliométrico , Carrera/fisiología , Levantamiento de Peso/fisiología , Adolescente , Atletas , Estudios Transversales , Prueba de Esfuerzo , Humanos , Masculino , Fútbol , Adulto Joven
4.
G Chir ; 33(5): 194-8, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22709459

RESUMEN

PURPOSE: Anastomotic strictures occur in 3-30% of colorectal anastomosis and one of the main causes may be a reaction to the presence of the metal staples used for suturing. The aim of this study was to evaluate the efficacy of a compression anastomosis ring using the memory shaped device in initial, i.e. nickel-titanium alloy (NiTi) for the prevention of colorectal anastomotic strictures. PATIENTS AND METHODS: A compression anastomosis ring device (NiTi CAR 27™) was used to perform compression anastomosis in 20 patients underwent left hemicolectomy and anterior resection of the rectum for carcinoma. An endoscopic check of the anastomosis was carried out at one month and at six months after surgery. RESULTS: In 2 patients (10%) a dehiscence of the anastomosis occurred on the fifth and the eighth postoperative day. No anastomotic strictures were observed in any of the other 18 patients at six months follow-up after surgery. CONCLUSION: Our preliminary results suggest that the use of a compression anastomosis ring might well be a valid method of preventing anastomotic strictures in colorectal surgery. Further studies involving a larger number of patients are needed in order to confirm these preliminary results.


Asunto(s)
Anastomosis Quirúrgica , Colon , Colectomía , Colon/cirugía , Constricción Patológica , Humanos , Recto/cirugía
5.
Phys Rev Lett ; 107(21): 215003, 2011 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-22181890

RESUMEN

Observations in the ASDEX Upgrade tokamak show a correlation between the gradient of the intrinsic toroidal rotation profile and the logarithmic gradient of the electron density profile. The intrinsic toroidal rotation in the center of the plasma reverses from co- to countercurrent when the logarithmic density gradients are large, and the turbulence is either dominated by trapped electron modes or is at the transition between ion temperature gradient and trapped electron modes. A study based on local gyrokinetic calculations suggests that the dominant trend in the observations can be explained by the combination of residual stresses produced by E × B and profile shearing mechanisms.

6.
Membranes (Basel) ; 11(8)2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-34436373

RESUMEN

The incumbent water stress scenario imposes wastewater valorisation to freshwater, promoting technology for its effective treatment. Wastewater from fertiliser factories is quite problematic because of its relevant acidity and solute content. Its treatment through vacuum membrane distillation (VMD) was evaluated through laboratory scale tests at 40 °C and 25 mbar vacuum pressure with polytetrafluoroethylene and polypropylene flat-sheet porous membranes. The wastewater from a partially disused Italian industrial site was considered. VMD distillate fluxes between 22 and 57.4 L m-2 h-1 (LMH), depending on the pore size of the membranes, along with very high retention (R > 99%) for anions (Cl-, NO3-, SO42-, PO43-), NH4+, and chemical oxygen demand (COD) were observed. Laboratory scale reverse osmosis (RO) tests at 25 °C and increasing of the operating pressure (from 20 bar to 40 bar) were carried out with a seawater desalination membrane for comparison purposes. Permeability values around 1.1 LMH/bar almost independently of the operating pressure were observed. Lower retentions than those measured from VMD tests were found. Finally, for any given RO operating pressure, the flux recovery ratio (FRR) calculated from permeate fluxes measured with pure water before and after wastewater treatment was always much lower that evaluated for VMD membranes.

7.
Phys Rev Lett ; 105(15): 155001, 2010 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-21230913

RESUMEN

The scaling of turbulence-driven heat transport with system size in magnetically confined plasmas is reexamined using first-principles based numerical simulations. Two very different numerical methods are applied to this problem, in order to resolve a long-standing quantitative disagreement, which may have arisen due to inconsistencies in the geometrical approximation. System size effects are further explored by modifying the width of the strong gradient region at fixed system size. The finite width of the strong gradient region in gyroradius units, rather than the finite overall system size, is found to induce the diffusivity reduction seen in global gyrokinetic simulations.

8.
Transplant Proc ; 37(6): 2791-2, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16182811

RESUMEN

INTRODUCTION: Cirrhosis predisposes to the development of hepatocellular carcinoma (HCC), demanding that these patients undergo follow-up with imaging methods for the early detection of neoplastic nodules. Morphologic study of the explanted livers allows identification of lesions not detected pre-operatively. OBJECTIVE: To assess the frequency and to characterize the HCC found incidentally at pathological evaluation of explanted cirrhotic livers. MATERIAL AND METHODS: Thirty patients had HCC diagnosed in explanted cirrhotic livers. The livers were sectioned at intervals of 0.5 cm. Each detached nodule was selected for microscopic study according to size, color and/or consistency. Retrospective analysis of the clinical records was performed comparing available data from various imaging methods. RESULTS: In 11 patients, 16 HCC had previously been identified in the explants by one or more imaging methods. In the other 19 explanted livers (63.3%), HCC was incidentally found. All HCC identified in 9 patients and some of them in 10 patients were incidentally found, varying from microscopic focuses to 2 cm diameter lesions. They varied from only one (5 cases) to multiple nodules (7 cases). DISCUSSION: Imaging methods may underestimate the number of HCC in cirrhotic livers. Histological study is an essential tool that can early detect tumor nodules not previously detected by imaging methods. In our study, although small, multicentric HCC were identified, illustrating the multifocal nature of the hepatic carcinogenesis. Future studies must correlate these findings with patient outcomes. CONCLUSION: Characterization of explanted cirrhotic livers for HCC is important for previously known and incidentally found lesions.


Asunto(s)
Carcinoma Hepatocelular/patología , Cirrosis Hepática/epidemiología , Neoplasias Hepáticas/patología , Hígado/patología , Biopsia , Carcinoma Hepatocelular/etiología , Hepatitis C/patología , Humanos , Cirrosis Hepática/etiología , Cirrosis Hepática/patología , Cirrosis Hepática Alcohólica/patología , Neoplasias Hepáticas/etiología
9.
Water Sci Technol ; 44(5): 61-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11695484

RESUMEN

Treatment of textile wastewaters by means of an ozonation pilot plant are described. Wastewaters used were produced by a dyeing and finishing factory and were first treated in an active sludge plant and filtrated through sand. In the appropriate conditions very high colour removal (95-99%) was achieved and the effluent could be reused in production processes requiring water of high quality as dyeing yarns or light colorations. Even if the chemical oxygen demand of treated waters was still in a range (75-120 mg/l, a decrease of up to 60%) that was usually considered to be too high for recycling purposes, recycling experiments were successful. The economical viability of the techniques implementation was also demonstrated and the industrial plant is currently under realisation under an EU financed project. The paper considers also the possible improvement of ozone diffusion by means of membrane contactors realised in a second pilot plant, in order to further reduce operating costs of the technique. With respect to traditional systems, the gas/liquid contact surface is much higher being that of the membrane. Ozone at the interface is therefore immediately solubilized and potentially consumed with no additional resistance to the mass transfer.


Asunto(s)
Colorantes/química , Membranas Artificiales , Oxidantes Fotoquímicos/química , Ozono/química , Industria Textil , Eliminación de Residuos Líquidos/métodos , Costos y Análisis de Costo , Difusión , Residuos Industriales , Solubilidad , Purificación del Agua/métodos
10.
Minerva Chir ; 44(12): 1627-31, 1989 Jun 30.
Artículo en Italiano | MEDLINE | ID: mdl-2771114

RESUMEN

Secondary prevention is undoubtedly a vital consideration in the early diagnosis of cancer of the large bowel. The examination of asymptomatic subjects considered to be at high risk of colorectal carcinomas will improve the prognosis for this tumour by identifying lesions at an early stage or, even better, pathologies considered precancerous. Rectosigmoidoscopy was therefore employed on a sample of asymptomatic geriatrics, at high risk because of their age. The examination of 245 elderly people revealed various asymptomatic conditions (haemorrhoids, rhagades, polyps, etc.) and, more importantly, 4 cases (1.6%) of rectosigmoid tumours, 2 of them Dukes stage A and 2 polyps in the initial phase of degeneration into malignancy. The paper concludes by emphasising the value of mass screening of the elderly and indeed of other high risk groups using a flexible rectosigmoidoscope, in the hope of identifying early-stage tumours or precancerous lesions with a view to reducing the incidence of colorectal carcinoma and therefore significantly improving the prognosis for that condition.


Asunto(s)
Neoplasias Colorrectales/prevención & control , Lesiones Precancerosas/prevención & control , Anciano , Anciano de 80 o más Años , Estudios de Evaluación como Asunto , Femenino , Hemorroides/diagnóstico , Humanos , Pólipos Intestinales/diagnóstico , Masculino , Persona de Mediana Edad , Proctoscopía , Sigmoidoscopía
11.
Minerva Chir ; 46(20): 1119-21, 1991 Oct 31.
Artículo en Italiano | MEDLINE | ID: mdl-1766559

RESUMEN

After a careful review of the Author's own case list and of the literature on this subject, Milligan-Morgans' technique is assessed and compared with different surgical techniques as far as early and late complications are concerned. The Authors conclude that the Milligan-Morgan technique is to be preferred because of its simplicity, safety and flexibility, particularly if associated with sphincterectomy, with or without rhagade, in order to prevent the cicatricial scars.


Asunto(s)
Hemorroides/cirugía , Canal Anal/cirugía , Cicatriz/prevención & control , Humanos , Métodos , Complicaciones Posoperatorias
12.
Minerva Chir ; 45(23-24): 1433-8, 1990 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-1708116

RESUMEN

Over the years the palliative treatment of neoplastic stenosis of the esophagus in patients who cannot be operated has seen a variation of endoscopic methods which aimed to reopen the alimentary canal either using simple dilatation, or the insertion of endoprostheses, or sclerosing injection or antiblastic therapy, or lastly using disobstructive laser therapy. In particular, the use of Neodymium YAG laser in endoscopic therapy for the deobstruction of neoplastic esophageal stenosis is currently widely used. More recently deobstruction of the stenosis may also be achieved using bipolar diathermocoagulation with BICAP following esophageal dilatation. Recent comparative studies of the use of BICAP and laser therapy in the treatment of neoplastic esophageal stenosis have tended to reveal the complementary characteristics of the two techniques. The present paper reports the Authors' experience in this respect which has been satisfactory with regard to both methods, in line with the findings of other studies. In the study of two groups of 8 patients treated with BICAP and laser therapy respectively, recanalisation was obtained in 100% of cases with good functional results in 75% of patients treated with BICAP and 87.5% of those receiving laser therapy. The time interval between one treatment session and the next in relation to the efficacy of the therapy was similar in both methods and ranged from a minimum of 4 weeks to a maximum of 12 weeks. Complications were scarce in both groups.


Asunto(s)
Adenocarcinoma/cirugía , Carcinoma de Células Escamosas/cirugía , Electrocoagulación , Neoplasias Esofágicas/cirugía , Estenosis Esofágica/etiología , Terapia por Láser , Adenocarcinoma/complicaciones , Anciano , Carcinoma de Células Escamosas/complicaciones , Neoplasias Esofágicas/complicaciones , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Paliativos
13.
Minerva Chir ; 45(23-24): 1439-45, 1990 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-1965017

RESUMEN

There are still marked differences in the current indications for breast screening proposed by the various international school of oncology. Epidemiological data to the effect that breast screening in asymptomatic women aged over 50 reduces the death rate due to breast cancer now appears to be widely accepted, but an analogous finding for women aged between 40-49 has not yet been confirmed. Following a brief analysis of the most important breast screening programmes carried out to date, the Authors report the preliminary results regarding the identification and biopsy of non-palpable breast lesions during the course of a screening programme in 1986 by the Dept. of Cancer Surgery. Of a total of 1128 breast scans in asymptomatic patients aged between 40 and 73, 24 suspect (1.9%) non-palpable lesions were found of which 5 (20.8%) proved to be carcinomas.


Asunto(s)
Adenofibroma/prevención & control , Neoplasias de la Mama/prevención & control , Carcinoma Intraductal no Infiltrante/prevención & control , Mamografía , Papiloma/prevención & control , Adenofibroma/diagnóstico , Adenofibroma/diagnóstico por imagen , Adulto , Factores de Edad , Anciano , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/diagnóstico por imagen , Carcinoma Intraductal no Infiltrante/diagnóstico , Carcinoma Intraductal no Infiltrante/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Enfermedad Fibroquística de la Mama/diagnóstico , Humanos , Persona de Mediana Edad , Papiloma/diagnóstico , Papiloma/diagnóstico por imagen , Pronóstico , Factores de Tiempo
14.
Minerva Chir ; 45(21-22): 1379-84, 1990 Nov.
Artículo en Italiano | MEDLINE | ID: mdl-2097563

RESUMEN

The aim of follow-up is essentially that of diagnosing possible recidivation at a relatively early and practically asymptomatic stage in order to optimise the results of appropriate treatment and to improve both the overall survival rate and the patient's quality of life. In spite of the correct and systematic planning of controls, the authors underline that in their experience only 64.7% of relapses are diagnosed during the asymptomatic phase. However, the authors have confirmed that the expectation of relapse has a barely significant influence on survival. After five years of first receiving treatment, 83% of patients with relapses diagnosed in a symptomatic phase had died, compared to 81.7% of those with relapses diagnosed during the asymptomatic phase. In conclusion, in spite of the fact that it is possible to obtain early diagnosis of recidivation during follow-up, it is equally true that this has no influence at all on the survival rate. However, irrespective of these results, the authors maintain that it is useful to follow patients undergoing breast surgery through a periodic follow-up to evaluate the evolution of disease and acquire an increasingly precise and definite knowledge of its natural history. The authors put forward a protocol for follow-up in which patients are divided into groups on the basis of lymph node status and pre- or postmenopause.


Asunto(s)
Neoplasias de la Mama/epidemiología , Carcinoma/epidemiología , Recurrencia Local de Neoplasia/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/cirugía , Carcinoma/mortalidad , Carcinoma/cirugía , Terapia Combinada , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/mortalidad
15.
Minerva Chir ; 44(9): 1349-51, 1989 May 15.
Artículo en Italiano | MEDLINE | ID: mdl-2761736

RESUMEN

Personal experience of intraoperative anterograde phlebography of the internal spermatic vein is reported. The use of this technique is suggested for controlling the result of internal spermatic vein ligature in cases of type I varicocele according to Coolsaet, diagnosed by preoperative retrograde phlebography. Early data make it possible to conclude that intraoperative anterograde phlebography is a valuable aid in reducing the frequency of recurrences.


Asunto(s)
Flebografía/métodos , Varicocele/cirugía , Adolescente , Adulto , Estudios de Evaluación como Asunto , Humanos , Cuidados Intraoperatorios , Ligadura , Masculino
16.
G Chir ; 12(4): 278-80, 1991 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-1911079

RESUMEN

The authors confirm the actuality and validity of decompressive cecostomy in emergency treatment of large bowel obstructions. Taking into account that staplers have substantially reduced the rate of complications and inconvenient of gastrointestinal surgery, their use of cecostomy closure is proposed. Advantages obtained with this technique, namely lack of infections and incisional hernias, are underlined.


Asunto(s)
Cecostomía/instrumentación , Engrapadoras Quirúrgicas , Enfermedad Aguda , Enfermedades del Ciego/cirugía , Cecostomía/métodos , Humanos , Obstrucción Intestinal/cirugía
17.
G Chir ; 12(5): 300-4, 1991 May.
Artículo en Italiano | MEDLINE | ID: mdl-1931521

RESUMEN

The Authors examine the most recent diagnostic methods of studying gastric carcinoma illustrating their limits and peculiarities. It is underlined that only an integrated use of these diagnostic methods may allow a right staging of the disease, which is very important for a correct therapeutic approach. After a review of the literature the Authors discuss on the extent gastric resection and lymphadenectomy must have to be considered radical and, at the same time, curative.


Asunto(s)
Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Gastrectomía , Humanos , Escisión del Ganglio Linfático , Estadificación de Neoplasias , Pronóstico , Estómago/patología , Neoplasias Gástricas/mortalidad , Factores de Tiempo
18.
G Chir ; 12(4): 251-4, 1991 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-1911072

RESUMEN

Thanks to the diffusion of the clinico-mammographic screening, in the last ten years a considerable increase of breast carcinomas diagnosed in a subclinical stage has been registered. The authors report the preliminary results of their experience in nonpalpable lesions of the breast and confirm the validity of conservative surgery for their treatment. Nonpalpable breast carcinomas must be considered as an early stage of palpable T1 tumors, for which validity of conservative surgery is largely demonstrated. Moreover, results are not compromised by possible multicentricity and/or positivity of axillary lymph nodes.


Asunto(s)
Neoplasias de la Mama/cirugía , Mama , Carcinoma/cirugía , Palpación , Adulto , Anciano , Biopsia con Aguja , Mama/patología , Neoplasias de la Mama/diagnóstico , Carcinoma/diagnóstico , Terapia Combinada , Femenino , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Mamografía , Mastectomía Segmentaria , Persona de Mediana Edad , Cuidados Posoperatorios
19.
IEEE Trans Biomed Eng ; 59(12): 3439-49, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22968204

RESUMEN

Face plastic surgery (PS) plays a major role in today medicine. Both for reconstructive and cosmetic surgery, achieving harmony of facial features is an important, if not the major goal. Several systems have been proposed for presenting to patient and surgeon possible outcomes of the surgical procedure. In this paper, we present a new 3-D system able to automatically suggest, for selected facial features as nose, chin, etc., shapes that aesthetically match the patient's face. The basic idea is suggesting shape changes aimed to approach similar but more harmonious faces. To this goal, our system compares the 3-D scan of the patient with a database of scans of harmonious faces, excluding the feature to be corrected. Then, the corresponding features of the k most similar harmonious faces, as well as their average, are suitably pasted onto the patient's face, producing k+1 aesthetically effective surgery simulations. The system has been fully implemented and tested. To demonstrate the system, a 3-D database of harmonious faces has been collected and a number of PS treatments have been simulated. The ratings of the outcomes of the simulations, provided by panels of human judges, show that the system and the underlying idea are effective.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Procedimientos de Cirugía Plástica/métodos , Cirugía Asistida por Computador/métodos , Simulación por Computador , Bases de Datos Factuales , Estética , Cara/anatomía & histología , Femenino , Humanos , Masculino , Planificación de Atención al Paciente , Resultado del Tratamiento
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