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1.
Phys Chem Chem Phys ; 21(35): 19288-19297, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31451821

RESUMO

This paper reports a facile, fast, and cost-effective method for the synthesis of three-dimensional (3D) porous AgNPs/Cu composites as SERS substrates for the super-sensitive and quantitative detection of food organic contaminations. Due to the 3D porous hotspot architecture and the strong plasmonic coupling between Ag and Cu, the porous AgNPs/Cu substrate achieves ultrasensitive detection of multiple analytes as low as 10-11 M (crystal violet, CV), 10-9 M (malachite green, MG), 10-11 M (acephate), and 10-9 M (thiram) even with a portable Raman device. Moreover, this 3D solid substrate has good signal uniformity (RSD < 11%) and superior stability (<14% signal loss), allowing for practical SERS detections. Importantly, by simply wiping the real sample surface using the substrate, it successfully detects CV and MG residues on crayfish, and the limit of detection (LOD) of CV and MG is determined to be 1.14 × 10-9 M and 0.94 × 10-7 M, respectively. Further, the substrate can also be applied to detect acephate on eggplant with a LOD of 1.41 × 10-9 M and thiram on an apple surface with a LOD of 1.04 × 10-7 M. Note that all these SERS detections on real samples have a broad dynamic concentration range and a good linear dependence. As a "proof of concept", multi-component detection on a real sample has also been demonstrated. This 3D solid substrate possesses excellent detection sensitivity, diversity, and accuracy, which allows rapid and reliable determination of toxic substances in foods.


Assuntos
Técnicas de Química Analítica/métodos , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Praguicidas/análise , Análise Espectral Raman , Animais , Técnicas de Química Analítica/economia , Cobre/química , Limite de Detecção , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Prata/química
2.
J Chin Med Assoc ; 80(10): 662-668, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28690121

RESUMO

BACKGROUND: To retrospectively evaluate the association between possible influencing factors and failed first attempts to inject a contrast agent intra-articularly under ultrasound (US)-guidance for direct magnetic resonance (MR) arthrography of the hip joint. METHODS: Ninety consecutive patients (38 women and 52 men; mean age, 42 years) undergoing US-guided hip MR arthrography (3 bilaterally) were retrospectively included in this study. The potential influencing factors were sex, age, body mass index (BMI), side of injection, target site, trajectory of the needle, additional use of needle tip rotation, failed first-attempt, and capsule elongation at the site of needle insertion. RESULTS: First-attempt failure was significantly associated with reduced capsule elongation at the target site and no additional use of needle tip rotation (OR 10.708; 95% CI 1.847-62.059; OR 3.518; 95% CI 1.120-11.047). Capsule elongation (sufficient for needle bevel insertion) was significantly larger at the femoral head-neck junction (5.2 ± 1.5 mm) than at the femoral head (2.9 ± 1.3 mm) (p < 0.001). CONCLUSION: Less capsular elongation of the femoral head and no additional use of needle tip rotation to reduce the difficulty in contrast material delivery can increase the first-attempt failure rate in patients undergoing US-guided hip arthrography.


Assuntos
Artrografia/métodos , Meios de Contraste/administração & dosagem , Imageamento por Ressonância Magnética/métodos , Ultrassonografia de Intervenção , Adulto , Feminino , Humanos , Injeções , Masculino , Estudos Retrospectivos
3.
Eur J Radiol ; 84(1): 77-85, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25455412

RESUMO

OBJECTIVE: To analyze the features of non-mass-like (NML) breast lesions on ultrasound (US) and determine their corresponding malignancy rate and to stratify these lesion patterns according to US BI-RADS categories. MATERIALS AND METHODS: One hundred sixty-four consecutive lesions were retrospectively classified into four types according to the US features, the corresponding positive predictive values (PPVs) were obtained. Clinical, imaging, and histopathological findings were reviewed. RESULTS: Among the 164 lesions, 39 (24%) were classified as type Ia, 14 (8%) as type Ib, 39 (24%) as type IIa, 19 (12%) as type IIb, 19 (12%) as type III, and 34 (21%) as type IV. The PPVs for malignancy were 21% for type Ia, 79% for type Ib, 10% for type IIa, 58% for type IIb, 16% for type III, and 21% for type IV. All NML lesions were classified as BI-RADS category 4a (type IIa), 4b (type Ia, III and IV) and 4c (type Ib and IIb) according to their PPVs. There was a significantly higher frequency of malignancy among lesions of type Ib and type IIb compared with the other types (P<0.01 for each). Lesions with associated calcifications, presence of abnormal axillary nodes, or a mammographic finding of suspected malignancy had a higher probability of malignancy (P<0.05 for each). CONCLUSION: US is useful in clarifying the indication for biopsy of NML lesions. The types of US classifications used in our study establish reliable references for the NML patterns when stratified according to the BI-RADS categories.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Sistemas de Informação em Radiologia/estatística & dados numéricos , Ultrassonografia Mamária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
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