Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Nature ; 629(8014): 1047-1054, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38778108

RESUMO

Wireless modules that provide telecommunications and power-harvesting capabilities enabled by radio-frequency (RF) electronics are vital components of skin-interfaced stretchable electronics1-7. However, recent studies on stretchable RF components have demonstrated that substantial changes in electrical properties, such as a shift in the antenna resonance frequency, occur even under relatively low elastic strains8-15. Such changes lead directly to greatly reduced wireless signal strength or power-transfer efficiency in stretchable systems, particularly in physically dynamic environments such as the surface of the skin. Here we present strain-invariant stretchable RF electronics capable of completely maintaining the original RF properties under various elastic strains using a 'dielectro-elastic' material as the substrate. Dielectro-elastic materials have physically tunable dielectric properties that effectively avert frequency shifts arising in interfacing RF electronics. Compared with conventional stretchable substrate materials, our material has superior electrical, mechanical and thermal properties that are suitable for high-performance stretchable RF electronics. In this paper, we describe the materials, fabrication and design strategies that serve as the foundation for enabling the strain-invariant behaviour of key RF components based on experimental and computational studies. Finally, we present a set of skin-interfaced wireless healthcare monitors based on strain-invariant stretchable RF electronics with a wireless operational distance of up to 30 m under strain.


Assuntos
Elasticidade , Eletrônica , Desenho de Equipamento , Ondas de Rádio , Pele , Estresse Mecânico , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Humanos , Eletrônica/instrumentação , Tecnologia sem Fio/instrumentação , Monitorização Fisiológica/instrumentação
2.
J Periodontol ; 94(8): 1008-1017, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36738270

RESUMO

BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs) are used for the management of anxiety and depression. Existing evidence shows their negative impact on implant osseointegration, survival rates, and peri-implant health. Currently, there are limited data on their effect on peri-implant marginal bone levels. The primary goal of this retrospective study is to evaluate the association between SSRIs use and marginal bone level (MBL) changes around osseointegrated dental implants over time. METHODS: Records from patients who received at least one dental implant between 2010 and 2021 were reviewed. Information related to medical history, SSRI use, and the implant site was obtained from patients' electronic charts. Mesial and distal MBLs were measured relative to the implant platform on digital intraoral radiographs, taken at the time of prosthesis installation and at the most recent follow-up visit. MBL changes were calculated. RESULTS: A total of 152 dental implants from 105 patients were included. The mean follow-up period was 46.97 ± 21.87 months. The mean MBL change was significantly greater for SSRI users (0.41 ± 0.76 mm) compared to non-users (0.04 ± 0.65 mm) [MD = 0.37 mm, p = 0.00, 95% CI: (-0.61)-(-0.15 mm)]. Mesial MBL change of 0.42 ± 0.84 mm and 0.02 ± 0.71 mm was noted for SSRI users and non-users, respectively. The distal MBL change was 0.4 ± 0.93 mm and 0.07 ± 0.73 mm, respectively. Smoking, sex, and implant location did not seem to influence the MBL differences between groups. CONCLUSIONS: Use of SSRIs is associated with greater marginal bone loss around osseointegrated dental implants in function for a mean period of 3.8 years.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Humanos , Estudos Retrospectivos , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Osseointegração , Osso e Ossos , Perda do Osso Alveolar/diagnóstico por imagem , Seguimentos , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Implantação Dentária Endóssea
3.
Ann Med Surg (Lond) ; 84: 104938, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36536729

RESUMO

Introduction: Testicular carcinoma is the most common cancer among males aged 15-34 years. The known risk factors for testicular cancer include undescended testis (cryptorchidism), testicular dysfunction, perinatal factors and prior history of cancer in one testis. We aimed to determine the diagnostic accuracy of color doppler ultrasound in diagnosis of testicular carcinoma using histopathology as GOLD STANDARD. Method: ology: A cross sectional study was conducted from July 2015 to Feb 2016 at the Department of Radiology, Jinnah Post Graduate Medical Center, Karachi. 311 subjects were selected through inpatient/outpatient or emergency department. Patients were evaluated for testicular carcinoma by color doppler ultrasound on Toshiba nemio. Finding of color doppler ultrasound was compared with histopathology. True positive, true negative, false positive, false negative as per operational definition was determined. Results: Mean age of the patients of the study was 41.76 ± 8.11 (30-50) and mean and SD of Duration of symptoms was 5.5 ± 3.5 (4-15) months. Of 175(56.27%) subjects diagnosed as testicular carcinoma on CDUS, only 160(48.55%) were subsequently found to have testicular carcinoma. sensitivity of CDUS in diagnosing scrotal diseases was 88.8% while specificity was 78.1%. Conclusion: We conclude that CDUS is an excellent, safe, and reliable method for evaluating patients with testicular carcinoma. It helps to improve patient's management, especially by preventing unnecessary surgical exploration. It is also convenient and easy to perform. But it has its own limitations, and requires adequate expertise and experience. Its results are also equipment dependent.

4.
Hum Exp Toxicol ; 30(7): 591-602, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20603273

RESUMO

The aim of this study was to investigate effects of lambda-cyhalothrin (LCT) on clinical, hematological, biochemical and pathological alterations in rabbits (Oryctolagus cuniculus). New Zealand white female rabbits (n = 24) of 4-5 months age having 997.92 ± 32.83 g weight were divided into four equal groups. Group A (control) received normal saline intraperitoneally (ip). Animals in groups B, C and D were treated with LCT 1.0, 4.0 and 8.0 mg/kg bw ip. Each group received seven consecutive doses at an interval of 48 hours. Blood and serum samples were collected at an interval of 96 hours. Blood analysis revealed a significant (p < 0.05) decrease in red blood cell and white blood cell counts, hemoglobin concentration and lymphocytes, while mean corpuscular hemoglobin concentration, mean corpuscular volume, neutrophils, monocytes and eosinophils were increased. Serum biochemical analysis revealed significant (p < 0.05) decrease in serum total proteins and serum albumin, while an increase was seen in serum alanine aminotransferase and aspartate aminotransferase activities compared with the control group. Serum globulin values varied non-significantly in all treatment groups as compared to control group. A dose-dependent increase in the incidence of micronucleated polychromatic erythrocyte was observed. All gross and histopathological lesions observed in LCT-treated rabbits were dose-dependent. Liver of the treated rabbits exhibited extensive perihepatitis, hyperplasia of bile duct, necrosis, hemorrhages and congestion. In lungs, there were hemorrhages, thickened alveolar walls, congestion, emphysema, collapsed alveoli and accumulation of extensive inflammatory cells. Kidneys were congested and hemorrhagic whereas renal parenchyma and stroma were normal. Microscopically, heart showed congestion of blood vessels and nuclear pyknosis, myodegeneration. It was concluded from the study that LCT produced toxicopathological alterations in rabbits in a dose-dependent manner. On the basis of the results, it can be suggested that overdosing of LCT be avoided while treating animals for ectoparasites.


Assuntos
Inseticidas/toxicidade , Nitrilas/toxicidade , Piretrinas/toxicidade , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/patologia , Testes de Química Clínica , Dano ao DNA , Feminino , Testes Hematológicos , Hemorragia/induzido quimicamente , Hemorragia/patologia , Injeções Intraperitoneais , Fígado/efeitos dos fármacos , Fígado/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Testes para Micronúcleos , Necrose/induzido quimicamente , Coelhos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA