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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 2587-2590, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30440937

RESUMO

Breast cancer is the most prevalent cancer among women. The most common method to detect breast cancer is mammography. However, interpreting mammography is a challenging task that requires high skills and is timeconsuming. In this work, we propose a computer-aided diagnosis (CAD) scheme for mammography based on transfer representation learning using the Inception-V3 architecture. We evaluate the performance of the proposed scheme using the INBreast database, where the features are extracted from different layers of the architecture. In order to cope with the small dataset size limitation, we expand the training dataset by generating artificial mammograms and employing different augmentation techniques. The proposed scheme shows great potential with a maximal area under the receiver operating characteristics curve of 0.91.


Assuntos
Neoplasias da Mama , Mamografia , Diagnóstico por Computador , Feminino , Humanos , Aprendizado de Máquina , Curva ROC , Interpretação de Imagem Radiográfica Assistida por Computador
2.
Br J Radiol ; 85(1014): e153-61, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21343322

RESUMO

OBJECTIVES: To investigate the feasibility of converting a computer-aided detection (CAD) scheme for digitised screen-film mammograms to full-field digital mammograms (FFDMs) and assessing CAD performance on a large database. METHODS: The database included 6478 FFDM images acquired on 1120 females, with 525 cancer cases and 595 negative cases. The database was divided into five case groups: (1) cancer detected during screening, (2) interval cancers, (3) "high-risk" recommended for surgical excision, (4) recalled but negative and (5) negative (not recalled). A previously developed CAD scheme for masses depicted on digitised images was converted and re-optimised for FFDM images while keeping the same image-processing structure. CAD performance was analysed on the entire database. RESULTS: The case-based sensitivity was 75.6% (397/525) for the current mammograms and 40.8% (42/103) for the prior mammograms deemed negative during clinical interpretation but "visible" during retrospective review. The region-based sensitivity was 58.1% (618/1064) for the current mammograms and 28.4% (57/201) for the prior mammograms. The CAD scheme marked 55.7% (221/397) and 35.7% (15/42) of the masses on both views of the current and the prior examinations, respectively. The overall CAD-cued false-positive rate was 0.32 per image, ranging from 0.29 to 0.51 for the five case groups. CONCLUSION: This study indicated that (1) digitised image-based CAD can be converted for FFDMs while performing at a comparable, or better, level; (2) CAD detects a substantial fraction of cancers depicted on prior examinations, albeit most having been marked only on one view; and (3) CAD tends to mark more false-positive results on "difficult" negative cases that are more visually difficult for radiologists to interpret.


Assuntos
Doenças Mamárias/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Mamografia/métodos , Intensificação de Imagem Radiográfica , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade
4.
Phys Rev Lett ; 90(25 Pt 1): 257201, 2003 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-12857159

RESUMO

The exchange bias and magnetic anisotropies in a Co layer on a single-crystalline FeF2 film have been determined between 30 and 300 K. By postulating that the coupling between the ferromagnet and the antiferromagnet persists above the Néel temperature (T(N)) we develop a model that quantitatively describes the exchange bias and the anisotropies over the whole temperature range, both above and below T(N). Using only the measured low temperature exchange bias and a distribution of blocking temperatures we explain (i) the temperature dependence of the bias, (ii) the magnitude of the anisotropies, (iii) the opposite sign of the first and second order anisotropies, (iv) the observed 1/T and 1/T(3) temperature dependencies of the first and second order uniaxial anisotropies above T(N), and (v) the decrease of the anisotropies below T(N).

5.
Phys Rev Lett ; 89(15): 157202, 2002 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-12366018

RESUMO

The critical exponent beta=0.16+/-0.02 for the random-field Ising model order parameter is determined using extinction-free magnetic x-ray scattering for Fe0.85Zn0.15F2 in magnetic fields of 10 and 11 T. The observed value is consistent with other experimental random-field critical exponents, but disagrees sharply with Monte Carlo and exact ground state calculations on finite-sized systems.

6.
Artigo em Inglês | MEDLINE | ID: mdl-9431531

RESUMO

The need and demand for oral medicine services in the United States and Canada was determined by a prospective survey of American Academy of Oral Medicine practitioners who attended the Academy's 1996 annual meeting. Of the 50 surveys returned from 149 eligible registrants, it was determined that, on the average, oral medicine practitioner respondents practiced 2.3 days per week and treated 8.7 patients per day; this amounts to more than 40,000 patient-care visits per year. Almost 90% of patients were treated because of medically compromising conditions, oral mucocutaneous disease, or chronic orofacial pain. Most of the care (52%) was provided in non-university settings. Most treatment involved the comprehensive evaluation of complex oral problems (36.7%), the prescription of medications (24.2%), or comprehensive dental treatment (21.8%) for patients with severe and life-threatening medical conditions. These results suggest that oral medicine services are needed and that demand for these services is high.


Assuntos
Serviços de Saúde Bucal/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Medicina Bucal/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Canadá/epidemiologia , Assistência Odontológica Integral/estatística & dados numéricos , Estado Terminal/epidemiologia , Assistência Odontológica para Doentes Crônicos/estatística & dados numéricos , Prescrições de Medicamentos/estatística & dados numéricos , Dor Facial/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Boca/epidemiologia , Pacientes/estatística & dados numéricos , Prática Profissional/estatística & dados numéricos , Estudos Prospectivos , Sociedades Odontológicas , Estados Unidos/epidemiologia
8.
Phys Rev B Condens Matter ; 54(8): R5291-R5294, 1996 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9986591
9.
Phys Rev Lett ; 76(24): 4624-4627, 1996 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-10061338
11.
Am J Med Sci ; 310(2): 65-7, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7631645

RESUMO

The authors describe a 22-year-old man with osteolytic mandibular and maxillary lesions. Biopsy substantiated the presence of Langerhans cell histiocytosis (eosinophilic granuloma). Levels of serum angiotensin-converting enzyme (ACE) were elevated repeatedly. After definitive therapy with excision and bone grafting, ACE levels returned to normal. The role of histiocytes in ACE production is discussed. Langerhans cell histiocytosis should be considered in the diagnosis of conditions occurring with elevation of serum ACE levels and clinical findings similar to sarcoidosis.


Assuntos
Histiocitose de Células de Langerhans/metabolismo , Peptidil Dipeptidase A/sangue , Adulto , Tecido Conjuntivo/patologia , Histiocitose de Células de Langerhans/patologia , Humanos , Masculino
14.
15.
Oral Surg Oral Med Oral Pathol ; 78(3): 319-22, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7970592

RESUMO

A case of diffuse, recurrent, suppurative sialadenitis and sialodochitis is presented. I believe this entity to be analogous to cheilitis glandularis and propose the name suppurative stomatitis glandularis.


Assuntos
Queilite/etiologia , Glândulas Salivares Menores/patologia , Sialadenite/complicações , Adulto , Cefalexina/uso terapêutico , Queilite/diagnóstico , Queilite/tratamento farmacológico , Dexametasona/uso terapêutico , Diagnóstico Diferencial , Feminino , Humanos , Prednisona/uso terapêutico , Recidiva , Sialadenite/diagnóstico , Sialadenite/tratamento farmacológico
17.
Eur J Cancer B Oral Oncol ; 30B(1): 1-7, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9135966

RESUMO

Leiomyoma is the most common benign neoplasm in the uterus and stomach but is rare in the oral cavity. There were only 5 oral cases in a series of 7748 leiomyomas of all sites. Benign smooth muscle neoplasms are classified into leiomyoma (solid leiomyoma), angiomyoma (vascular leiomyoma) and epithelioid leiomyoma (leiomyoblastoma). 6 cases diagnosed as leiomyoma were retrieved from the files of two oral biopsy services over the past 25 years. A light microscopic study including trichrome and phosphotungstic acid haematoxylin (PTAH) stains, and an immunohistochemical study with the following markers: desmin, muscle specific actin, myoglobin, vimentin, S-100 protein, neuron-specific enolase, factor VIII and Ulex europeus were done with suitable controls. The haematoxylin and eosin and Masson's trichrome stains supported a diagnosis of leiomyoma in all 6 cases but PTAH was positive in only 3 of them. The immunohistochemical study confirmed the diagnosis of leiomyoma in 3 cases. The other 3 were identified as granular cell tumour, myofibroma and neurofibroma, respectively. The review of the literature contributed the following data: mean age was 41 and median age 39 in 134/142 patients. A male sex prevalence 72/137 patients (54.0%) was noted. The lips were the most common site with 39 cases (27.46%) followed by the tongue 26 (18.30%), cheeks and palate 22 (15.49%), gingiva 12 (8.45%), and mandible 8 (5.63%). Prognosis of oral leiomyomas is excellent. Immunohistochemistry is a precise and reliable method for definitive diagnosis of oral leiomyoma.


Assuntos
Leiomioma/patologia , Neoplasias Bucais/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiomioma/patologia , Biópsia , Criança , Pré-Escolar , Feminino , Neoplasias Gengivais/patologia , Humanos , Imuno-Histoquímica , Lactente , Leiomioma/epidemiologia , Neoplasias Labiais/patologia , Masculino , Neoplasias Mandibulares/patologia , Pessoa de Meia-Idade , Neoplasias Bucais/epidemiologia , Neoplasias Palatinas/patologia , Estudos Retrospectivos , Neoplasias da Língua/patologia
18.
Phys Rev B Condens Matter ; 48(11): 8365-8375, 1993 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10007031
19.
Oral Surg Oral Med Oral Pathol ; 75(6): 733-8, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8515987

RESUMO

Squamous odontogenic tumor is a distinct entity-separate from the more aggressive ameloblastoma. Only 33 squamous odontogenic tumors have been reported since the first description in 1975. We report three additional cases including the first completely extraosseous case.


Assuntos
Neoplasias Mandibulares/patologia , Neoplasias Maxilares/patologia , Neoplasias Bucais/patologia , Tumores Odontogênicos/patologia , Adulto , Idoso , Epitélio/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/patologia
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