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1.
Life (Basel) ; 13(3)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36983938

RESUMO

3D rotational angiography is now increasingly used in routine neuroendovascular procedures--in particular, for situations where the analysis of two overlayed sets of volume imaging proves useful for planning the treatment strategy or for confirming the optimal apposition of the intravascular devices used. The aim of this study is to identify and describe the decision algorithm for which the overlay function of 3D rotational angiography volumes, high-resolution contrast-enhanced flat panel detector CT adapted for intravascular devices (VasoCT/DynaCT), non-enhanced flat detector C-arm volume acquisition functionality integrated with the angiography equipment (XperCT/DynaCT), and isovolumetric MRI volumes were all used in treatments performed in a series of 29 patients. Two superposed 3DRA volumes were used in the treatment aneurysms located at the junction of two vascular territories and for arteriovenous malformations with compartments fed from different vascular territories. The superposition function of a preoperatively acquired 3DRA volume and a postoperatively acquired VasoCT volume provides accurate information about the apposition of neuroendovascular endoprostheses used in the treatment of aneurysms. The automatic overlay function generated by the 3D workstation is particularly useful, but in about 50% of cases it requires manual operator-dependent correction, requiring a certain level of experience. In our experience, multimodal imaging brings an important benefit, both in the treatment decision algorithm and in the assessment of neuroendovascular treatment efficacy.

2.
Diagnostics (Basel) ; 13(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36832150

RESUMO

Artificial intelligence (AI) is a term that covers a multitude of techniques that are used in a manner that tries to reproduce human intelligence. AI is helpful in various medical specialties that use imaging for diagnostic purposes, and gastroenterology is no exception. In this field, AI has several applications, such as detecting and classifying polyps, detecting the malignancy in polyps, diagnosing Helicobacter pylori infection, gastritis, inflammatory bowel disease, gastric cancer, esophageal neoplasia, and pancreatic and hepatic lesions. The aim of this mini-review is to analyze the currently available studies regarding AI in the field of gastroenterology and hepatology and to discuss its main applications as well as its main limitations.

3.
Small ; 19(2): e2204662, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36373704

RESUMO

Physical patterns represent potential surface cues for promoting osteogenic differentiation of stem cells and improving osseointegration of orthopedic implants. Understanding the early cell-surface interactions and their effects on late cellular functions is essential for a rational design of such topographies, yet still elusive. In this work, fluidic force microscopy (FluidFM) and atomic force microscopy (AFM) combined with optical and electron microscopy are used to quantitatively investigate the interaction of preosteoblasts with 3D-printed patterns after 4 and 24 h of culture. The patterns consist of pillars with the same diameter (200 nm) and interspace (700 nm) but distinct heights (500 and 1000 nm) and osteogenic properties. FluidFM reveals a higher cell adhesion strength after 24 h of culture on the taller pillars (32 ± 7 kPa versus 21.5 ± 12.5 kPa). This is associated with attachment of cells partly on the sidewalls of these pillars, thus requiring larger normal forces for detachment. Furthermore, the higher resistance to shear forces observed for these cells indicates an enhanced anchorage and can be related to the persistence and stability of lamellipodia. The study explains the differential cell adhesion behavior induced by different pillar heights, enabling advancements in the rational design of osteogenic patterns.


Assuntos
Osteogênese , Impressão Tridimensional , Microscopia de Força Atômica , Microscopia Eletrônica
4.
In Vivo ; 36(3): 1349-1353, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35478161

RESUMO

BACKGROUND: Human infection with the SARS-CoV-2 virus has caused a pandemic characterized by a plethora of diseases, of which those affecting the internal organs and nervous system can have severe, life-threatening consequences. Among the manifestations of the disease at the viral entry site, diseases in oral mucosa adnexa are rarely reported. This case report describes a COVID-19-associated aggravating parotid gland disease. CASE REPORT: The 47-year-old, SARS-CoV-2-positive male patient, already hospitalized and now in need of ventilation, had been referred for intensive care treatment due to increasing respiratory problems. A unilateral swelling of the cheek was noticed, the cause of which was initially a parotid gland infection. Examination ruled out mechanical causes of the parotid gland. During further treatment, the patient developed a parotid abscess, which was drained extra orally. CONCLUSION: The oral cavity is primarily considered as a reservoir of the pathogen. There is an increasing number of reports detailing inflammation of the major salivary glands associated with SARS-CoV-2 virus. Knowledge of this association facilitates therapeutic decisions.


Assuntos
COVID-19 , Gastroenteropatias , Abscesso/diagnóstico , Abscesso/etiologia , COVID-19/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Glândula Parótida , SARS-CoV-2
5.
Nutrients ; 14(8)2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35458129

RESUMO

Magnesium orotate has been cited in the medical literature for the past three years as a possible adjuvant in some pediatric and adult gastroenterological disorders associated with dysbiosis. Studies also focus on the possibility of adding magnesium orotate in psychiatric disorders' treatment, such as major depression and anxiety. The most relevant element in these studies is the efficiency of magnesium orotate therapy in cases with both gastroenterological and psychiatric symptoms. This article proposes a literature review, focused on the studies published in the last three years, targeting magnesium orotate treatment and probiotic supplementation in patients with both digestive and psychiatric symptoms. Moreover, this review will compare the efficiency of magnesium orotate and probiotics within both the pediatric and adult communities, focusing on the possibility of gut-brain axis modulation and its involvement in the clinical evolution of these patients.


Assuntos
Gastroenteropatias , Microbiota , Probióticos , Adulto , Eixo Encéfalo-Intestino , Criança , Gastroenteropatias/tratamento farmacológico , Humanos , Ácido Orótico/análogos & derivados , Probióticos/uso terapêutico
6.
Chirurgia (Bucur) ; 116(6): 700-717, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34967715

RESUMO

Introduction: The treatment of blunt splenic injuries showed major evolutionary changes, from fundamental/ basic splenectomy to nonoperative and endovascular treatment, "catheter surgery". Currently, in Trauma Centers, splenic angioembolization is considered the first-line intervention in trauma. This article presents the Bucharest Emergency Clinical Hospital experience in the use of splenic angioembolization, a therapeutic solution in accordance with contemporary practice and literature. Methods: This retrospective study includes patients with splenic trauma by blunt mechanism, in which diagnostic / therapeutic angiography was performed, hospitalized in the Clinical Emergency Hospital Bucharest between January 2006 and December 2019. The main endpoints of the study were: post-traumatic mortality, the need for surgery (laparoscopic/classic) to resolve splenic bleeding, the number of days of hospitalization, the need for hospitalization for more than 1 day in the intensive care unit, the day when the platelet count began to increase, the evolution of laboratory parameters (hospitalization, preangiography, postangiography/embolization, discharge). A secondary endpoint of the study was the frequency of complications that did not require surgery. Results: During the mentioned period in 64 patients treated nonoperatively, diagnostic angiography was performed (27 cases, group B) or therapeutic angiography (37 cases, group A). 26.56% of cases were 55 years old (55-81 years old), the predominance of males being obvious (62.5%). The mean value of the ISS was 21.7 +- 10.4, and 71.87% of cases presented ISS 16. The mean value of the ISS was 21.7 +- 10.4, and 71.87% of cases presented ISS 16. The degree of splenic injury (American Association for the Surgery of Trauma-Organ Injury Scale) presented the mean value 2.95. The degree of splenic lesion was statistically significantly more severe in group A (p 0.001) and preangiography hemoglobin values were significantly lower compared to hospitalization values (p 0.001) indicating the persistence of hemorrhage. Procedural failures occurred in 4.68% of cases, with zero mortality. Conclusions: Splenic interventional radiology is a safe, effective and rational procedure. The development of therapeutic protocols is necessary to allow maximum use of this procedure.


Assuntos
Traumatismos Abdominais , Embolização Terapêutica , Ferimentos não Penetrantes , Idoso , Idoso de 80 Anos ou mais , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Radiologia Intervencionista , Estudos Retrospectivos , Esplenectomia , Centros de Traumatologia , Resultado do Tratamento , Ferimentos não Penetrantes/diagnóstico por imagem , Ferimentos não Penetrantes/cirurgia
7.
Polymers (Basel) ; 12(7)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630145

RESUMO

Degeneration of articular cartilage (AC) is a common healthcare issue that can result in significantly impaired function and mobility for affected patients. The avascular nature of the tissue strongly burdens its regenerative capacity contributing to the development of more serious conditions such as osteoarthritis. Recent advances in bioprinting have prompted the development of alternative tissue engineering therapies for the generation of AC. Particular interest has been dedicated to scaffold-based strategies where 3D substrates are used to guide cellular function and tissue ingrowth. Despite its extensive use in bioprinting, the application of polycaprolactone (PCL) in AC is, however, restricted by properties that inhibit pro-chondrogenic cell phenotypes. This study proposes the use of a new bioprintable poly(ester urea) (PEU) material as an alternative to PCL for the generation of an in vitro model of early chondrogenesis. The polymer was successfully printed into 3D constructs displaying adequate substrate stiffness and increased hydrophilicity compared to PCL. Human chondrocytes cultured on the scaffolds exhibited higher cell viability and improved chondrogenic phenotype with upregulation of genes associated with type II collagen and aggrecan synthesis. Bioprinted PEU scaffolds could, therefore, provide a potential platform for the fabrication of bespoke, pro-chondrogenic tissue engineering constructs.

8.
New J Phys ; 22(6)2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34790030

RESUMO

The ability to create linear systems that manifest broadband nonreciprocal wave propagation would provide for exquisite control over acoustic signals for electronic filtering in communication and noise control. Acoustic nonreciprocity has predominately been achieved by approaches that introduce nonlinear interaction, mean-flow biasing, smart skins, and spatio-temporal parametric modulation into the system. Each approach suffers from at least one of the following drawbacks: the introduction of modulation tones, narrow band filtering, and the interruption of mean flow in fluid acoustics. We now show that an acoustic media that is non-local and active provides a new means to break reciprocity in a linear fashion without these deleterious effects. We realize this media using a distributed network of interlaced subwavelength sensor-actuator pairs with unidirectional signal transport. We exploit this new design space to create a stable metamaterial with non-even dispersion relations and electronically tunable nonreciprocal behavior over a broad range of frequencies.

9.
J Neuroradiol ; 47(3): 227-232, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-30658137

RESUMO

INTRODUCTION: The treatment of wide-neck bifurcation aneurysms is still challenging despite the use of new techniques, such as Y-stenting, the waffle-cone technique and intrasaccular flow disrupters, in recent years. Moreover, the use of flow diverter stents in bifurcation aneurysms has been proposed by several teams, although the results remain controversial. This study aims to evaluate the feasibility and efficacy of Y-stent assisted coiling of bifurcation aneurysms with braided stents. METHODS: We retrospectively reviewed all patients in whom Y-stenting with braided stents had been performed in our center. Six patients were identified and analyzed. Technical success, complications, angiographic outcomes, procedural data, and follow-up controls are reported here. This study was approved by our local ethical committee. RESULTS: Technical success was achieved in all procedures. Overall procedure-related morbidity and mortality was 0%. In the immediate post-treatment angiography, adequate occlusion (neck remnant or total occlusion) was observed in all patients. Short- and long-term follow-up angiography showed adequate occlusion of the aneurysms. CONCLUSIONS: In this small, retrospective single-center analysis we showed that Y-stent assisted coiling with braided stents is a safe and feasible technique. Moreover, it has a high immediate occlusion rate and very good long-term stability.


Assuntos
Embolização Terapêutica/métodos , Aneurisma Intracraniano/terapia , Idoso , Angiografia Cerebral , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Stents , Resultado do Tratamento
10.
J Acoust Soc Am ; 145(6): 3633, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31255100

RESUMO

This paper presents the design and experimental demonstration of a passive broadband acoustic pressure enhancing metafluid in air. The design is optimized for fabrication via three-dimensional (3D) printing and takes advantage of the property of acoustic pressure to enhance sound as the sound passes with minimal insertion loss from the background medium into a high impedance fluid. Numerical simulations and experimental measurements of the fabricated structure show that the metafluid enhances the sound pressure level by 7 dB in more than one octave without introducing sound distortions. Moreover, the metafluid is subwavelength in size and does not increase the aperture of the sensor. These results provide an excellent path toward improving the sensitivity of compact acoustic sensors without employing active elements.

11.
J Neurointerv Surg ; 11(5): 511-515, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30655358

RESUMO

BACKROUND: The treatment of wide neck bifurcation aneurysms remains challenging despite the introduction of new techniques (Y stenting, waffle cone technique, or flow diverter stents). The Woven EndoBridge (WEB) device is an innovative solution for this type of cerebral aneurysm. A new WEB 17 is now available and has been designed to offer smaller sized devices to optimize navigability and delivery. METHODS: Between February 2017 and April 2018 all patients treated with the WEB 17 device in our center were retrospectively reviewed. 25 patients with 28 non-ruptured aneurysms were identified and analyzed. Three patients with two aneurysms both treated with the WEB device were identified. RESULTS: The device was successfully deployed in all cases. Procedure related morbidity was 4% and mortality was 0%. In one case, a delayed postprocedural thromboembolic event occurred owing to device protrusion. Technical success, complications, angiographic outcomes, procedural data, and follow-ups are reported. The modified Rankin Scale score at discharge was 0 for 24 patients (96%). At the 3, 6, or 9 month follow-up, angiograms were taken of 21 of the 25 patients (84%) (24 of 28 aneurysms had been controlled); 3 patients (3 aneurysms) did not receive angiographic follow-up at the time of submission of this work. Complete occlusion was achieved in 22 of 24 aneurysms (91.66%), and 2 of 24 aneurysm (8.33%) showed a neck remnant. CONCLUSIONS: The WEB 17 is safe and technically feasible, according to this retrospective single center analysis. For very small bifurcation aneurysms, the WEB 17 seems to have lower complication rates than stent assisted techniques. However, further studies are needed to evaluate the complication rate and long term efficiency.


Assuntos
Implante de Prótese Vascular , Prótese Vascular , Aneurisma Intracraniano/cirurgia , Adulto , Idoso , Prótese Vascular/efeitos adversos , Angiografia Cerebral , Embolização Terapêutica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos , Stents , Resultado do Tratamento , Adulto Jovem
12.
J Neurointerv Surg ; 11(4): 386-389, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30291206

RESUMO

BACKGROUND: Woven EndoBridge (WEB) deployment remains challenging in aneurysms with a complex shape or orientation. OBJECTIVE: To show that embolization of wide-neck bifurcation aneurysms using the WEB device balloon remodeling-assisted technique is a feasible and elegant endovascular solution compared with other techniques, such as balloon remodeling or stent-assisted coiling. MATERIALS AND METHODS: 10 cases (10 aneurysms in 9 patients) of balloon remodeling-assisted WEB treatment of unruptured complex bifurcation aneurysms were treated in our institution and retrospectively analyzed. Details of clinical presentations, technical details, perioperative and postoperative complications, and outcomes were collected. Immediate and long-term angiographic results were also evaluated. RESULTS: Aneurysms included six middle cerebral artery aneurysms, one anterior communicating artery aneurysm, one posterior communicating artery aneurysm, one basilar artery aneurysm, and one T-shaped carotid aneurysm. Mean dome width was 6.55 mm, mean neck size 4.5 mm, mean height 4.79 mm, and mean dome-to-neck ratio was 1:1.46. Treatment was performed exclusively with the balloon remodeling-assisted WEB technique in all cases. The device was successfully deployed in every case. Periprocedural thromboembolic or hemorrhagic events did not occur. The modified Rankin Scale score at discharge was 0 for all patients. At mid-term or long-term angiographic follow-up, adequate occlusion was observed in 7 aneurysms from 8 controlled cases (87.5%), and one patient (2 aneurysms) did not have angiographic follow-up. CONCLUSION: The balloon remodeling-assisted WEB technique seems to be a safe and effective solution for endovascular treatment of unruptured wide-neck bifurcation aneurysms with specific complex anatomy. However, further studies are needed to evaluate the rate of complications and long-term efficacy.


Assuntos
Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Stents , Adulto , Idoso , Angiografia Cerebral/métodos , Embolização Terapêutica/métodos , Procedimentos Endovasculares/instrumentação , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Alta do Paciente/tendências , Complicações Pós-Operatórias/diagnóstico por imagem , Estudos Retrospectivos , Tromboembolia/diagnóstico por imagem , Tromboembolia/terapia , Resultado do Tratamento
13.
Nat Commun ; 9(1): 5299, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30546016

RESUMO

Noise is a long standing societal problem that has recently been linked to serious health consequences. Despite decades of research on noise mitigation techniques, existing methods have significant limitations including inability to silence broadband noise and shield large volumes. Here we show theoretically and experimentally that acoustic bianisotropic materials with non-zero strain to momentum coupling are remarkably effective sound barriers. They surpass state-of-the-art sound isolators in terms of attenuation, bandwidth, and shielded volume. We implement our barriers with very compact active meta-atoms that owe their small size to their local response to external sound. Moreover, our active approach is not constrained by feedback stabilization requirements, in stark contrast with all traditional active sound control systems. Consequently, bianisotropic sound barriers have the potential to revolutionize noise control technologies and provide much needed solutions to an increasingly important and difficult challenge.

14.
Sci Rep ; 6: 35437, 2016 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-27739472

RESUMO

Acoustic holographic rendering in complete analogy with optical holography are useful for various applications, ranging from multi-focal lensing, multiplexed sensing and synthesizing three-dimensional complex sound fields. Conventional approaches rely on a large number of active transducers and phase shifting circuits. In this paper we show that by using passive metamaterials as subwavelength pixels, holographic rendering can be achieved without cumbersome circuitry and with only a single transducer, thus significantly reducing system complexity. Such metamaterial-based holograms can serve as versatile platforms for various advanced acoustic wave manipulation and signal modulation, leading to new possibilities in acoustic sensing, energy deposition and medical diagnostic imaging.

15.
J Acoust Soc Am ; 139(6): 3325, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27369158

RESUMO

The paper presents a method to design and characterize mechanically robust solid acoustic metamaterials suitable for operation in dense fluids such as water. These structures, also called metafluids, behave acoustically as inertial fluids characterized by anisotropic mass densities and isotropic bulk modulus. The method is illustrated through the design and experimental characterization of a metafluid consisting of perforated steel plates held together by rubber coated magnetic spacers. The spacers are very effective at reducing the effective shear modulus of the structure, and therefore effective at minimizing the ensuing coupling between the shear and pressure waves inside the solid effective medium. Inertial anisotropy together with fluid-like acoustic behavior are key properties that bring transformation acoustics in dense fluids closer to reality.

16.
J Gastrointestin Liver Dis ; 25(2): 249-52, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27308659

RESUMO

Progressive esophageal carcinoma can infiltrate the surrounding tissues with subsequent development of a fistula, most commonly between the esophagus and the respiratory tract. The endoscopic placement of covered self-expanding metallic stents (SEMS) is the treatment of choice for malignant esophageal fistulas and should be performed immediately, as a fistula formation represents a potential life-threatening complication. We report the case of a 64-year-old male diagnosed with esophageal carcinoma, who had a 20Fr surgical gastrostomy tube inserted before chemo- and radiotherapy and was referred to our department for complete dysphagia, cough after swallowing and fever. The attempt to insert a SEMS using the classic endoscopic procedure failed. Then, a fully covered stent was inserted, as the 0.035" guide wire was passed through stenosis retrogradely by using an Olympus Exera II GIF-N180 (4.9 mm in diameter endoscope) via surgical gastrostomy, with a good outcome for the patient. The retrograde approach via gastrostomy under endoscopic/fluoroscopic guidance with the placement of a fully covered SEMS proved to be the technique of choice, in a patient with malignant esophageal fistula in whom other methods of treatment were not feasible.


Assuntos
Fístula Esofágica/terapia , Neoplasias Esofágicas/complicações , Esofagostomia/instrumentação , Gastrostomia , Metais , Radiografia Intervencionista , Stents , Fístula Esofágica/diagnóstico por imagem , Fístula Esofágica/etiologia , Neoplasias Esofágicas/patologia , Esofagoscópios , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Radiografia Intervencionista/métodos , Resultado do Tratamento
17.
Chirurgia (Bucur) ; 111(1): 74-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26988545

RESUMO

Acute lower gastrointestinal bleeding is a major problem worldwide, being a rare and life threatening condition, with a mortality rate situated between 2 and 4%. Acute lower gastrointestinal bleeding is solvent for 1 - 2% of the entire hospital emergencies, 15% presenting as massive bleeding and up to 5% requiring surgery. Lower gastrointestinal bleeding can be classified depending on their location in the small or large intestine. The small bowel is the rarest site of lower gastrointestinal bleeding, at the same time being the commonest cause of obscure bleeding. 5% of total lower GI bleeding appears in the small bowel. When endoscopic therapy associated with medical treatment are insufficient, endovascular intervention can be lifesaving. Unfortunately in some rare cases of acute lower gastrointestinal bleeding with hemo-dynamic instability and the angiography performed being unable to locate the source of bleeding, the last therapeutic resource remains surgery. In the following we exemplify two cases of acute lower gastrointestinal bleeding which were resolved in different ways, followed by a thorough description of the different types of available treatment and finally, in the conclusions, we systematize the most important stages of the management algorithm in acute lower gastrointestinal bleeding.


Assuntos
Angiodisplasia/terapia , Diverticulite/cirurgia , Embolização Terapêutica , Hemorragia Gastrointestinal/terapia , Divertículo Ileal , Fístula Vascular/cirurgia , Doença Aguda , Adolescente , Adulto , Algoritmos , Angiodisplasia/complicações , Angiodisplasia/diagnóstico , Angiografia , Colonoscopia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Diverticulite/complicações , Diverticulite/diagnóstico , Embolização Terapêutica/métodos , Emergências , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Humanos , Íleo/patologia , Masculino , Resultado do Tratamento , Fístula Vascular/diagnóstico , Fístula Vascular/etiologia
18.
Rom J Morphol Embryol ; 56(3): 1017-25, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26662134

RESUMO

Localized duodenal neoplasms are relatively rare entities, most often representing invasions of the duodenum by malignant masses developed in the duodeno-pancreatic region. The paper makes a more exact analysis of radiological semiology of duodenal localized tumors and seeks to determine through this analysis the role of radiological examinations in the support for the anatomopathologist. The study group included 17 cases of duodenal localized tumors, nine cases of which have been shown to be vaterian ampulloma and eight malignant tumors of the duodenum. All cases were CT (computed tomography) examined and two-thirds were performed conventional radiological examinations, prior to CT examination. Pre-operatively, all cases were evaluated endoscopically, and in three of them bile prostheses were made. CT examination protocol included a native acquisition and post-administration of intravenous contrast agent in both the arterial phase and in parenchymal and venous phase. The acquisition was made with 3 mm thin sections, subsequently coronal and sagittal plane reconstructions being made. The paper tries to establish possible correlations between the morphopathological aspect and the radio-imaging semiological characteristics of lesions.


Assuntos
Neoplasias Duodenais/diagnóstico por imagem , Neoplasias Duodenais/patologia , Adulto , Ductos Biliares/patologia , Meios de Contraste , Feminino , Vesícula Biliar/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Carga Tumoral
19.
Proc Natl Acad Sci U S A ; 112(34): 10595-8, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26261314

RESUMO

Designing a "cocktail party listener" that functionally mimics the selective perception of a human auditory system has been pursued over the past decades. By exploiting acoustic metamaterials and compressive sensing, we present here a single-sensor listening device that separates simultaneous overlapping sounds from different sources. The device with a compact array of resonant metamaterials is demonstrated to distinguish three overlapping and independent sources with 96.67% correct audio recognition. Segregation of the audio signals is achieved using physical layer encoding without relying on source characteristics. This hardware approach to multichannel source separation can be applied to robust speech recognition and hearing aids and may be extended to other acoustic imaging and sensing applications.


Assuntos
Acústica/instrumentação , Resinas Acrílicas , Butadienos , Auxiliares de Audição , Poliestirenos , Processamento de Sinais Assistido por Computador , Localização de Som , Percepção Auditiva , Simulação por Computador , Desenho de Equipamento , Retroalimentação Sensorial , Humanos , Manufaturas , Teste de Materiais , Modelos Teóricos , Fonética , Impressão Tridimensional , Interface para o Reconhecimento da Fala
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