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1.
Nature ; 620(7975): 768-775, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37612392

RESUMO

Models of artificial intelligence (AI) that have billions of parameters can achieve high accuracy across a range of tasks1,2, but they exacerbate the poor energy efficiency of conventional general-purpose processors, such as graphics processing units or central processing units. Analog in-memory computing (analog-AI)3-7 can provide better energy efficiency by performing matrix-vector multiplications in parallel on 'memory tiles'. However, analog-AI has yet to demonstrate software-equivalent (SWeq) accuracy on models that require many such tiles and efficient communication of neural-network activations between the tiles. Here we present an analog-AI chip that combines 35 million phase-change memory devices across 34 tiles, massively parallel inter-tile communication and analog, low-power peripheral circuitry that can achieve up to 12.4 tera-operations per second per watt (TOPS/W) chip-sustained performance. We demonstrate fully end-to-end SWeq accuracy for a small keyword-spotting network and near-SWeq accuracy on the much larger MLPerf8 recurrent neural-network transducer (RNNT), with more than 45 million weights mapped onto more than 140 million phase-change memory devices across five chips.

2.
J Bone Joint Surg Br ; 89(3): 396-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17356159

RESUMO

Arrest of growth of the distal radius is rare but will produce deformity of the wrist. We corrected angular deformity and shortening of the distal radius by epiphysiolysis and gradual lengthening without a corrective osteotomy.


Assuntos
Remodelação Óssea/fisiologia , Rádio (Anatomia)/fisiopatologia , Rádio (Anatomia)/cirurgia , Traumatismos do Punho/cirurgia , Alongamento Ósseo/métodos , Criança , Feminino , Humanos , Radiografia , Rádio (Anatomia)/diagnóstico por imagem , Resultado do Tratamento , Traumatismos do Punho/diagnóstico por imagem , Traumatismos do Punho/fisiopatologia , Articulação do Punho/diagnóstico por imagem , Articulação do Punho/cirurgia
4.
Biomarkers ; 5(3): 219-24, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-23889223

RESUMO

Maras powder is a kind of smokeless tobacco used in the south-eastern region of Turkey. The present study was carried out to assess possible DNA damage in exfoliated oral cells of Maras powder users by analysing the frequencies of micronuclei (MN), which is a simple and reliable biomarker for genotoxic damage and to screen for the detection of site-specific differences in the frequencies of MN. The mean (±SD) MN frequency in the inner lip mucosa site was 1.27(±0.55) % for Maras powder users and 0.88(±0.47) % for non-smoking control subjects (p < 0.05) and 0.82(±0.40) % for the buccal site of Maras powder users (p < 0.01). There was no significant site-specific difference between the inner lip site and the buccal mucosa site 0.73(±0.43) % in the MN frequency of non-smoking control subjects (p > 0.05). There was no significant effect of daily consumption of Maras powder, and duration of usage on MN frequencies. The present study suggests that the oral use of smokeless tobacco represents a genotoxic hazard and also that use of MN from a single site may be misleading as a marker of genotoxic exposure. Habitual use of Maras powder should be taken into account and could be considered unsafe.

5.
J Comput Assist Tomogr ; 23(5): 721-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10524855

RESUMO

PURPOSE: The purpose of this study was to describe the MR findings of chondroblastoma with pathologic correlation. METHOD: In 22 patients with pathologically proven chondroblastoma, MR signal characteristics were correlated with pathological findings. RESULTS: On T2-weighted images, 12 (55%) lesions were hyperintense with hypointense areas in 9 lesions, whereas 10 (45%) were hypointense. Therefore, 19 of 22 (86%) lesions with pathologic correlation had hypointense areas entirely (n = 10) or partly (n = 9) on T2-weighted images. On gadolinium-enhanced images, 13 (59%) lesions showed lobular enhancement and 9 (41%) showed marginal and septal enhancement. Low signal intensity on T2-weighted MR images was most strongly associated with an abundance of immature chondroid matrix, hypercellularity of the chondroblasts, calcifications, and hemosiderin on histology. CONCLUSION: Chondroblastoma was found to show hypointense portions on T2-weighted images. Signal intensity on T1- and T2-weighted MR images in chondroblastoma was dependent on the amounts of histopathological components.


Assuntos
Neoplasias Ósseas/diagnóstico , Condroblastoma/diagnóstico , Imageamento por Ressonância Magnética , Adolescente , Adulto , Biópsia , Neoplasias Ósseas/patologia , Osso e Ossos/patologia , Condroblastoma/patologia , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Estudos Retrospectivos
6.
Radiology ; 209(1): 197-202, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9769832

RESUMO

PURPOSE: To correlate the findings of nonossifying fibroma at magnetic resonance (MR) imaging with those at pathologic examination. MATERIALS AND METHODS: In 19 patients (age range, 8-25 years; mean age, 14 years) with pathologically proved nonossifying fibroma, MR images were analyzed for signal intensity and patterns of contrast enhancement. Findings at MR imaging and biopsy were correlated. RESULTS: On T1-weighted images, all nonossifying fibromas had low signal intensity compared with that of skeletal muscle. On T2-weighted images, 15 lesions (79%) were hypointense and four (21%) were hyperintense. On gadolinium-enhanced images, intense contrast enhancement was seen throughout 15 lesions (heterogeneous pattern in 12 and homogeneous in three) and in the margins and septa in four. Extensive hypercellular fibrous tissue and hemosiderin seen at pathologic examination were depicted with low signal intensity on T2-weighted MR images. CONCLUSION: The distinguishing features of nonossifying fibroma included hypointensity and septation on T2-weighted images. Signal intensity on T1- and T2-weighted MR images and the patterns of contrast enhancement were dependent on the amounts of hypercellular fibrous tissue, hemosiderin, hemorrhage, collagen, foamy histiocytes, and bone trabeculae.


Assuntos
Doenças do Desenvolvimento Ósseo/diagnóstico , Osso e Ossos/patologia , Imageamento por Ressonância Magnética , Adolescente , Adulto , Biópsia , Doenças do Desenvolvimento Ósseo/patologia , Osso e Ossos/diagnóstico por imagem , Criança , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Masculino , Radiografia
7.
Skeletal Radiol ; 27(3): 157-60, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9554007

RESUMO

Parosteal osteosarcoma is an uncommon, low-grade malignant bone tumor and is found in an older age group than conventional osteosarcoma. We present a talar parosteal osteosarcoma that recurred twice in a 2-year-old child. To our knowledge, this is the youngest patient reported with a parosteal osteosarcoma. The talus is an unusual site for parosteal osteosarcoma. Inadequate resection due to a diagnosis of juxtacortical chondroma resulted in recurrence of the tumor. The age of the patient, the thick cartilaginous cap, and well-differentiated trabecular bone all contributed to the critical erroneous diagnosis.


Assuntos
Neoplasias Ósseas/epidemiologia , Recidiva Local de Neoplasia , Osteossarcoma Justacortical/epidemiologia , Tálus/patologia , Neoplasias Ósseas/diagnóstico , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Osteossarcoma Justacortical/diagnóstico
8.
Int Orthop ; 14(2): 175-7, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2373564

RESUMO

Five cases of tuberculosis of the ischiopubic ramus are reported. All presented with abscesses. Treatment by simple curettage and INH, rifampicin and ethambutol given for 18 to 24 months gave satisfactory results in the 4 patients who were children. The one adult had severe disruption of the symphysis pubis, and sacroiliac involvement; a good result was obtained after bone grafting and fixation with a plate.


Assuntos
Antituberculosos/uso terapêutico , Ísquio , Osso Púbico , Tuberculose Osteoarticular/terapia , Adulto , Placas Ósseas , Transplante Ósseo , Criança , Pré-Escolar , Terapia Combinada , Curetagem , Feminino , Humanos , Ísquio/diagnóstico por imagem , Masculino , Osso Púbico/diagnóstico por imagem , Radiografia , Tuberculose Osteoarticular/diagnóstico por imagem
9.
Int Orthop ; 14(1): 79-83, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2341219

RESUMO

This study was undertaken to clarify the effects of topically injected chymopapain on the spinal cord and peripheral nerves in rabbits, and also the effect of ganglioside on sciatic nerves which had been damaged by chymopapain. There were no abnormal macroscopic or microscopic findings when chymopapain was injected around the sciatic nerve sheath or around the spinal dura mater, but when it was injected directly into the nerve sheath there was immediate paralysis and severe axonal necrosis; the Schwann sheath remained intact and there was haemorrhage. Injection into the dura resulted in massive haemorrhage, perivascular neutrophil infiltration and necrosis of grey matter. In those treated with ganglioside, regeneration of the damaged sciatic nerve was shorter than in those not so treated.


Assuntos
Quimopapaína/efeitos adversos , Gangliosídeos/uso terapêutico , Hidrogênio , Tecido Nervoso/efeitos dos fármacos , Nervo Isquiático/efeitos dos fármacos , Animais , Quimopapaína/administração & dosagem , Gangliosídeos/administração & dosagem , Gangliosídeos/farmacologia , Injeções Epidurais , Necrose/induzido quimicamente , Regeneração Nervosa , Tecido Nervoso/fisiologia , Coelhos , Nervo Isquiático/patologia , Nervo Isquiático/fisiologia , Hemorragia Subaracnóidea/induzido quimicamente
10.
Gastrointest Radiol ; 13(2): 109-11, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3360244

RESUMO

Gastric leiomyoblastomas are rare tumors between leiomyomas and leiomyosarcomas in terms of their malignant potential. This article describes 2 cases of exogastric cystic gastric leiomyoblastoma with unusual location and computed tomographic (CT) appearance. The CT findings of these cases were unlike those of usual smooth muscle tumors, but closely simulated cystadenomatous tumor of the ovary or pancreas.


Assuntos
Leiomioma/diagnóstico por imagem , Neoplasias Gástricas/diagnóstico por imagem , Idoso , Cistos/diagnóstico por imagem , Cistos/patologia , Humanos , Leiomioma/patologia , Masculino , Radiografia , Neoplasias Gástricas/patologia
11.
Int Orthop ; 10(1): 69-73, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3721657

RESUMO

We have attempted to clarify the serial histological changes in the growing spine of dogs following posterior fixation with acrylic cement. Twenty-four male mongrel dogs aged 8 weeks were used for the study. The lumbar spine from L.3 to L.5 was fixed posteriorly with acrylic cement. Three dogs were then sacrificed every four weeks up to 32 weeks, and the histological changes of the vertebral disc, growth plate and vertebral bodies were observed by light microscopy. Thinning of the growth plate and distortion of the cartilage columns has been demonstrated, but premature fusion of the growth plate did not result and vertebral body growth continued. Anterior wedging of the intervertebral disc was seen with some thinning of the bony trabeculae of the vertebral body. Degeneration of the nucleus pulposus resulted, with replacement by fibrous tissue. The normal horizontal arrangement of the fibres of the annulus fibrosus altered to a vertical configuration by 32 weeks.


Assuntos
Metilmetacrilatos , Fusão Vertebral , Coluna Vertebral/patologia , Animais , Cães , Lâmina de Crescimento/patologia , Cifose/patologia , Vértebras Lombares/patologia , Metilmetacrilato , Fatores de Tempo
12.
Int Orthop ; 8(4): 247-53, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2410378

RESUMO

Subtotal synovectomy was performed on the right knee joints of 20 immature and 20 mature rabbits, and articular cartilage from the femoral and tibial condyles and the patellae was examined at 1, 3, 5 and 12 weeks after operation. Specimens from the unoperated left knees provided the controls. Each specimen was examined macroscopically and with histological (H-E stain) and histochemical (safranin-O stain) techniques for abnormalities in structure, cell population, stain intensity and distribution. The femoral articular cartilage was most affected by synovectomy. The tibial articular cartilage was only moderately affected and the patellar articular cartilage was even less affected. The histochemical changes were transient and reversible, being more severe and prolonged in the mature animals. No changes in either group were noted on gross inspection or in the H-E stained sections.


Assuntos
Cartilagem Articular/patologia , Articulação do Joelho/cirurgia , Sinovectomia , Animais , Cartilagem Articular/metabolismo , Fêmur , Histocitoquímica , Técnicas Histológicas , Patela , Coelhos , Coloração e Rotulagem , Tíbia , Fatores de Tempo
13.
Clin Orthop Relat Res ; (182): 264-9, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6546362

RESUMO

The chronologic development of normal and regenerated menisci in immature and adult rabbits, studied by gross, histologic, and histochemical means, revealed that grossly regenerated menisci were less glossy and smaller than normal, with blunt margins and firm attachments to the synovial membrane. The normal meniscus of five-week-old rabbits consisted of fibroblasts and fibrocytes without cartilage cells. In 12-week-old rabbits fibrocytes in the normal meniscus had been transformed into round or oval cells lying within lacunae, the halos of which stained with safranin O. In the typical regenerated meniscus fibrocartilage cells appeared 12 weeks after meniscectomy in young rabbits and 24 weeks after meniscectomy in adult rabbits. Cartilaginous transformation occurred infrequently and only in isolated areas of the meniscus. Cartilaginous transformation in regenerated menisci appeared in 10.6% of the knees in young rabbits and in 8.1% in adult rabbits.


Assuntos
Meniscos Tibiais/fisiologia , Regeneração , Fatores Etários , Animais , Cartilagem/citologia , Cartilagem/fisiologia , Fibroblastos , Histocitoquímica , Meniscos Tibiais/citologia , Meniscos Tibiais/cirurgia , Coelhos
14.
Int Orthop ; 4(1): 13-8, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7399775

RESUMO

In an experimental study the authors tried to clarify the effect on vertebral growth and spinal curvature in dogs following fixation of the posterior elements of the spine at different levels using bone cement. In three separate experimental groups a segment of the dorsal spine, the dorso-lumbar spine or the lumbar spine was securely fixed with bone cement incorporating a radio-opaque wire marker. Growth of the spine was observed with renal X-rays over a six-month period and the following results obtained: 1. Growth in height of the vertebra was not affected by the fixation; 2. The intervertebral disc spaces widened anteriorly and narrowed posteriorly even when fracture of the bone cement occurred; 3. Increasing lordosis developed in all three experimental groups even when a physiological kyphosis was normally present. The greatest increase occurred in the lumbar spine; 4. Fracture of the cement occurred consistently when attempting to secure the dorso-lumbar junction.


Assuntos
Cimentos Ósseos , Fusão Vertebral/métodos , Coluna Vertebral/crescimento & desenvolvimento , Animais , Cães , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/crescimento & desenvolvimento , Pseudoartrose/etiologia , Radiografia , Fusão Vertebral/efeitos adversos , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/cirurgia
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