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1.
Phys Med ; 64: 1-9, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31515007

RESUMO

BACKGROUND: Microcalcification clusters in mammograms can be considered as early signs of breast cancer. However, their detection is a very challenging task because of different factors: large variety of breast composition, highly textured breast anatomy, impalpable size of microcalcifications in some cases, as well as inherent low contrast of mammograms. Thus, the need to support the clinicians' work with an automatic tool. METHODS: In this work a three-phases approach for clustered microcalcification detection is presented. Specifically, it is made up of a pre-processing step, aimed at highlighting potentially interesting breast structures, followed by a single microcalcification detection step, based on Hough transform, that is able to grasp the innate characteristic shape of the structures of interest. Finally, a cluster identification step to group microcalcifications is carried out by means of a clustering algorithm able to codify expert domain rules. RESULTS: The detection performance of the proposed method has been evaluated on 364 mammograms of 182 patients obtaining a true positive ratio of 91.78% with 2.87 false positives per image. CONCLUSIONS: Experimental results demonstrated that the proposed method is able to detect microcalcification clusters in digital mammograms showing performance comparable to different methodologies exploited in the state-of-art approaches, with the advantage that it does not require any training phase and a large set of data. The performance of the proposed approach remains high even for more difficult clinical cases of mammograms of young women having high-density breast tissue thus resulting in a reduced contrast between microcalcifications and surrounding dense tissues.


Assuntos
Calcinose/diagnóstico por imagem , Diagnóstico por Computador/métodos , Mamografia/métodos , Adulto , Idoso , Algoritmos , Automação , Neoplasias da Mama/complicações , Neoplasias da Mama/diagnóstico por imagem , Calcinose/complicações , Reações Falso-Positivas , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Pessoa de Meia-Idade
2.
Biomed Res Int ; 2018: 9032408, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30140703

RESUMO

Breast cancer is the main cause of female malignancy worldwide. Effective early detection by imaging studies remains critical to decrease mortality rates, particularly in women at high risk for developing breast cancer. Breast Magnetic Resonance Imaging (MRI) is a common diagnostic tool in the management of breast diseases, especially for high-risk women. However, during this examination, both normal and abnormal breast tissues enhance after contrast material administration. Specifically, the normal breast tissue enhancement is known as background parenchymal enhancement: it may represent breast activity and depends on several factors, varying in degree and distribution in different patients as well as in the same patient over time. While a light degree of normal breast tissue enhancement generally causes no interpretative difficulties, a higher degree may cause difficulty to detect and classify breast lesions at Magnetic Resonance Imaging even for experienced radiologists. In this work, we intend to investigate the exploitation of some statistical measurements to automatically characterize the enhancement trend of the whole breast area in both normal and abnormal tissues independently from the presence of a background parenchymal enhancement thus to provide a diagnostic support tool for radiologists in the MRI analysis.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adulto , Idoso , Meios de Contraste , Feminino , Humanos , Aumento da Imagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
3.
Phys Rev Lett ; 116(24): 241105, 2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27367381

RESUMO

Cosmic-ray electrons and positrons are a unique probe of the propagation of cosmic rays as well as of the nature and distribution of particle sources in our Galaxy. Recent measurements of these particles are challenging our basic understanding of the mechanisms of production, acceleration, and propagation of cosmic rays. Particularly striking are the differences between the low energy results collected by the space-borne PAMELA and AMS-02 experiments and older measurements pointing to sign-charge dependence of the solar modulation of cosmic-ray spectra. The PAMELA experiment has been measuring the time variation of the positron and electron intensity at Earth from July 2006 to December 2015 covering the period for the minimum of solar cycle 23 (2006-2009) until the middle of the maximum of solar cycle 24, through the polarity reversal of the heliospheric magnetic field which took place between 2013 and 2014. The positron to electron ratio measured in this time period clearly shows a sign-charge dependence of the solar modulation introduced by particle drifts. These results provide the first clear and continuous observation of how drift effects on solar modulation have unfolded with time from solar minimum to solar maximum and their dependence on the particle rigidity and the cyclic polarity of the solar magnetic field.

4.
G Chir ; 32(4): 188-93, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21554849

RESUMO

BACKGROUND: The ingestion of caustic substances is one of the most difficult conditions to be treated in Emergency Department. PATIENTS AND METHODS: The medical records of patients with caustic ingestion and hospitalized from 2003 to 2008 at the Division of General Emergency Surgery with Polyspecialistic Observation of AORN "A. Cardarelli "in Naples, have been revalued. RESULTS: From 2003 to 2008, 58 patients with caustic ingestion were admitted to our Division. Ten of these patients (17.24%) underwent surgery. Six patients underwent oesophageal and gastric resection with cervical esophagostomy and alimentary digiunostomy in emergency; two underwent exploratory laparotomy, two had gastroenteroanastomosis for antropyloric stenosis. One patient underwent new operation for a complication. In total, three reconstructions of oesophagus with colon were performed . Of the six patients undergoing esofagogastrectomy, two died in the first postoperative day, but four have passed the acute phase. CONCLUSIONS: There is no universally accepted diagnostic and therapeutic procedure for the management of these patients, who are often left - as it appears in literature - to the personal experience of the surgeon who is dealing with this situation.


Assuntos
Queimaduras Químicas/cirurgia , Cáusticos/toxicidade , Trato Gastrointestinal Superior/lesões , Trato Gastrointestinal Superior/cirurgia , Feminino , Humanos , Masculino
5.
Phys Rev Lett ; 102(5): 051101, 2009 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-19257498

RESUMO

A new measurement of the cosmic-ray antiproton-to-proton flux ratio between 1 and 100 GeV is presented. The results were obtained with the PAMELA experiment, which was launched into low-Earth orbit on-board the Resurs-DK1 satellite on June 15th 2006. During 500 days of data collection a total of about 1000 antiprotons have been identified, including 100 above an energy of 20 GeV. The high-energy results are a tenfold improvement in statistics with respect to all previously published data. The data follow the trend expected from secondary production calculations and significantly constrain contributions from exotic sources, e.g., dark matter particle annihilations.

6.
Radiol Med ; 113(4): 477-85, 2008 Jun.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-18536871

RESUMO

The implementation of a database of digitised mammograms is discussed. The digitised images were collected beginning in 1999 by a community of physicists in collaboration with radiologists in several Italian hospitals as a first step in developing and implementing a computer-aided detection (CAD) system. All 3,369 mammograms were collected from 967 patients and classified according to lesion type and morphology, breast tissue and pathology type. A dedicated graphical user interface was developed to visualise and process mammograms to support the medical diagnosis directly on a high-resolution screen. The database has been the starting point for developing other medical imaging applications, such as a breast CAD, currently being upgraded and optimised for use in a distributed environment with grid services, in the framework of the Instituto Nazionale di Fisicia Nucleare (INFN)-funded Medical Applications on a Grid Infrastructure Connection (MAGIC)-5 project.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Bases de Dados Factuais , Mamografia/métodos , Interpretação de Imagem Radiográfica Assistida por Computador , Adulto , Idoso , Feminino , Humanos , Itália , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
7.
G Chir ; 29(4): 145-8, 2008 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-18419977

RESUMO

Choriocarcinoma is a rare malignant genital tract tumor, arising in the uterus or in the testis. Primary or metastatic choriocarcinomas of the gastrointestinal tract are infrequent. We report a case of a testis choriocarcinoma presenting as jejunal metastasis with perforation. Histology revealed the origin of this metastatic tumor, allowing us to recognize the primary neoplasm of the testis. A review of literature with PubMed since 1964 and of the references of the papers retrieved was performed. Since 1933 only 30 cases of jejunal choriocarcinomas have been described in literature. In 13 cases jejunal choriocarcinoma presented gastrointestinal hemorrhage, in 4 intestinal intussusception and in 1 case upper abdominal pain and vomiting. Only 5 cases of jejunal perforation have been described. The case presented is the first in literature of jejunal perforation from a metastatic choriocarcinoma of the testis.


Assuntos
Coriocarcinoma/secundário , Perfuração Intestinal/etiologia , Neoplasias do Jejuno/secundário , Neoplasias Testiculares/patologia , Coriocarcinoma/complicações , Coriocarcinoma/cirurgia , Humanos , Perfuração Intestinal/cirurgia , Neoplasias do Jejuno/complicações , Neoplasias do Jejuno/cirurgia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
8.
G Chir ; 28(6-7): 253-7, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-17626768

RESUMO

The Authors report a case of acute abdomen caused by a colic stenosis due to eosinophilic gastroenteritis. It is a not frequent disease, often clinically unclear: in the medical literature the Authors have found only 346 cases in publications concerning the period January 1990 - December 2005. The clinical presentation is very changeable, related to the involved site of alimentary tract and to the level of eosinophilic infiltration of the wall. There are no diagnosis criteria universally acknowledged and the most efficient procedure is thought being the intestinal biopsy which enables showing the infiltration of the digestive wall. The cure is above all medical with administration of corticosteroid: surgery surely has a less important role, reserved to the cases with acute onset.


Assuntos
Abdome Agudo/etiologia , Colite/complicações , Eosinofilia/complicações , Humanos , Masculino , Pessoa de Meia-Idade
9.
Med Phys ; 34(12): 4901-10, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18196815

RESUMO

A computer-aided detection (CAD) system for the selection of lung nodules in computer tomography (CT) images is presented. The system is based on region growing (RG) algorithms and a new active contour model (ACM), implementing a local convex hull, able to draw the correct contour of the lung parenchyma and to include the pleural nodules. The CAD consists of three steps: (1) the lung parenchymal volume is segmented by means of a RG algorithm; the pleural nodules are included through the new ACM technique; (2) a RG algorithm is iteratively applied to the previously segmented volume in order to detect the candidate nodules; (3) a double-threshold cut and a neural network are applied to reduce the false positives (FPs). After having set the parameters on a clinical CT, the system works on whole scans, without the need for any manual selection. The CT database was recorded at the Pisa center of the ITALUNG-CT trial, the first Italian randomized controlled trial for the screening of the lung cancer. The detection rate of the system is 88.5% with 6.6 FPs/CT on 15 CT scans (about 4700 sectional images) with 26 nodules: 15 internal and 11 pleural. A reduction to 2.47 FPs/CT is achieved at 80% efficiency.


Assuntos
Diagnóstico por Computador/métodos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Modelos Biológicos , Doses de Radiação , Tomografia Computadorizada por Raios X , Algoritmos , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico por imagem , Redes Neurais de Computação , Curva ROC
10.
Med Phys ; 33(8): 3066-75, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16964885

RESUMO

Mass localization plays a crucial role in computer-aided detection (CAD) systems for the classification of suspicious regions in mammograms. In this article we present a completely automated classification system for the detection of masses in digitized mammographic images. The tool system we discuss consists in three processing levels: (a) Image segmentation for the localization of regions of interest (ROIs). This step relies on an iterative dynamical threshold algorithm able to select iso-intensity closed contours around gray level maxima of the mammogram. (b) ROI characterization by means of textural features computed from the gray tone spatial dependence matrix (GTSDM), containing second-order spatial statistics information on the pixel gray level intensity. As the images under study were recorded in different centers and with different machine settings, eight GTSDM features were selected so as to be invariant under monotonic transformation. In this way, the images do not need to be normalized, as the adopted features depend on the texture only, rather than on the gray tone levels, too. (c) ROI classification by means of a neural network, with supervision provided by the radiologist's diagnosis. The CAD system was evaluated on a large database of 3369 mammographic images [2307 negative, 1062 pathological (or positive), containing at least one confirmed mass, as diagnosed by an expert radiologist]. To assess the performance of the system, receiver operating characteristic (ROC) and free-response ROC analysis were employed. The area under the ROC curve was found to be Az = 0.783 +/- 0.008 for the ROI-based classification. When evaluating the accuracy of the CAD against the radiologist-drawn boundaries, 4.23 false positives per image are found at 80% of mass sensitivity.


Assuntos
Inteligência Artificial , Neoplasias da Mama/diagnóstico por imagem , Armazenamento e Recuperação da Informação/métodos , Mamografia/métodos , Reconhecimento Automatizado de Padrão/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Sistemas de Informação em Radiologia , Algoritmos , Análise por Conglomerados , Sistemas de Gerenciamento de Base de Dados , Bases de Dados Factuais , Feminino , Humanos , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Minerva Chir ; 59(5): 489-93, 2004 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-15494676

RESUMO

AIM: Restoration of colorectal continuity is the second step of the procedure originally described by H. Hartmann for the treatment of sigmoid colon cancers. It is a safe, but complex procedure, that needs a meticulous surgical technique and is associated with a significant morbidity in as many as 40% of cases. For this reason, many patients are not submitted to reversal of the colostomy. METHODS: The authors report their experience: 32 patients underwent colostomy closure after Hartmann's procedure during the last 8 years. RESULTS: The mortality rate was nil, but post-operative complications occurred in 12 patients (37.5%), namely: wound infection (11 patients) and anastomotic leak (2 patients). CONCLUSION: In light of this, it could be wiser to perform, in the patients affected with benign pathology, and in those affected with limited malignant pathology (T3), resection of the diseased segment of colon and primary anastomosis with temporary ileostomy, reserving Hartmann's procedure to patients unsuitable to one step treatment because of their poor general and local conditions.


Assuntos
Colo/cirurgia , Doenças do Colo/cirurgia , Colostomia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Interpretação Estatística de Dados , Feminino , Humanos , Laparotomia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Doenças do Colo Sigmoide/cirurgia , Neoplasias do Colo Sigmoide/cirurgia
12.
Minerva Chir ; 55(11): 799-802, 2000 Nov.
Artigo em Italiano | MEDLINE | ID: mdl-11265154

RESUMO

The occurrence of an angiosarcoma of the residual breast after conservative surgery and adjuvant radiotherapy for early mammary carcinoma is a very rare event. In western countries only 57 cases have been published in the literature (5 in Italy) since the first described case in 1987. Radiotherapy seems to be the most important etiological factor in the development of the neoplasm. Diagnosis is often delayed, owing to the "benign" aspect of the lesion. The only effective treatment is residual mastectomy, because chemotherapy is ineffective. The prognosis is often dismal, because of the aggressive behaviour of the lesion in most cases. The case of a patient with a multicentric secondary angiosarcoma of the breast recently operated on is described.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Carcinoma Ductal de Mama/radioterapia , Hemangiossarcoma/patologia , Neoplasias Induzidas por Radiação/patologia , Idoso , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Feminino , Hemangiossarcoma/cirurgia , Humanos , Mastectomia Segmentar , Neoplasias Induzidas por Radiação/cirurgia , Radioterapia Adjuvante
13.
G Chir ; 20(8-9): 348-50, 1999.
Artigo em Italiano | MEDLINE | ID: mdl-10444922

RESUMO

From January 1995 to December 1997, 170 patients with perforation of benign peptic ulcer (89 of them with perforation of iuxtapiloric ulcer, 54 duodenal and 27 gastric) were operated at A. Cardarelli's Emergence Department in Naples. Totally 153 repairs, 11 gastric or gastroduodenal resections, 4 ulcer excisions, 1 fundoplicatio and 1 transduodenal drainage were made. The last one was the only case of mortality. In 3 patients only dehiscence of the repair was registered (1.9% of complications). To reduce the risk of underevaluation of gastric neoplastic lesion or refractory ulcer to medical treatment, it's necessary to associate the repair with endoscopic follow-up and postoperative accurate medical therapy. So it's possible to obtain good results.


Assuntos
Úlcera Péptica Perfurada/cirurgia , Úlcera Péptica/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Serviços Médicos de Emergência , Endoscopia , Feminino , Seguimentos , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/complicações
15.
Chir Ital ; 40(2): 170-6, 1988 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-3168086

RESUMO

The Authors present a case who occurred to their observation concerning a patient undergoing subtotal gastrectomy for cancer four years ago which have developed a phytobezoar in the gastric stump, treated with enzymatic dissolution with acetylcysteine associated with metoclopramide . According to the Literature, the Authors point out the etiology, pathogenesis and therapy of this non rate consequence of the gastric surgery.


Assuntos
Acetilcisteína/uso terapêutico , Bezoares/tratamento farmacológico , Gastrectomia/efeitos adversos , Metoclopramida/uso terapêutico , Estômago , Acetilcisteína/administração & dosagem , Quimioterapia Combinada , Humanos , Masculino , Metoclopramida/administração & dosagem , Pessoa de Meia-Idade
16.
Riv Neurol ; 56(5): 325-35, 1986.
Artigo em Italiano | MEDLINE | ID: mdl-3576069

RESUMO

They have reported a case of multiple hepatic and cerebral metastasis of hypernephroma. The cerebral metastasis, probably after the hepatic one, are present respectively at a cerebellar and parietal-occipital level; the latter is the cause of a cerebral haemorrhage in a quite precocious phase of development.


Assuntos
Neoplasias Encefálicas/secundário , Carcinoma de Células Renais/secundário , Hemorragia Cerebral/etiologia , Hematoma/etiologia , Neoplasias Renais/complicações , Neoplasias Encefálicas/complicações , Carcinoma de Células Renais/complicações , Neoplasias Cerebelares/secundário , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Lobo Occipital , Lobo Parietal
17.
Mol Gen Genet ; 201(1): 7-13, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3932822

RESUMO

An electrophoretic mobility variant of phenoloxidase in a lz stock of Drosophila melanogaster was identified as the A3 component of the phenoloxidase complex by using two different activators to study enzyme activity-natural activator isolated from pupae and 50% 2-propanol. The structural gene for the A3 proenzyme, Dox-3, was not associated with lz on the X chromosome; it mapped to the right of rdo (53.1) and left of M(2)m in the second linkage group. The lz locus affects the differentiation of the crystal cell, the type of hemocyte that carries prophenoloxidase(s) in paracrystalline form. Alleles of lz lacking paracrystalline inclusions in their hemocytes do not have phenoloxidase activity whereas alleles with paracrystalline inclusions have enzyme activity. The presence of proenzyme in the paracrystalline inclusions was demonstrated by in situ activation with natural activator or propanol followed by incubation in buffered dopa.


Assuntos
Catecol Oxidase/genética , Drosophila melanogaster/enzimologia , Genes , Monofenol Mono-Oxigenase/genética , Alelos , Animais , Deleção Cromossômica , Cruzamentos Genéticos , Drosophila melanogaster/genética , Ativação Enzimática , Feminino , Heterozigoto , Masculino , Monofenol Mono-Oxigenase/metabolismo , Mutação
18.
Minerva Med ; 69(21): 1443-54, 1978 Apr 30.
Artigo em Italiano | MEDLINE | ID: mdl-683548

RESUMO

Difficulties still encountered in the coordinated interdisciplinary management of solid tumours in hospitals are discussed. Preliminary results obtained with a polychemical and immunostimulating protocol based on Corynebacterium parvum (introduced in 1973) in breast tumours immediately after surgery and in the advanced stage are presented. Two out of eight subjects with advanced forms died. Partial regression or a steady state were noted in the remainder. No locoregional recurrences or metastases were observed from 1 to 2 yr after the commencement of treatment in 22 patients treated in the immediate post-operative phase. These results are considered satisfactory, though a final evaluation would be premature. Stress is laid on the importance of immunostimulating management in the avoiding the immunodepression caused by the administration of drugs.


Assuntos
Antineoplásicos/uso terapêutico , Vacinas Bacterianas/uso terapêutico , Neoplasias da Mama/terapia , Corynebacterium/imunologia , Adulto , Idoso , Neoplasias da Mama/cirurgia , Quimioterapia Combinada , Estudos de Avaliação como Assunto , Feminino , Humanos , Pessoa de Meia-Idade , Cuidados Pós-Operatórios
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