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1.
Thyroid ; 23(1): 58-63, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22973946

RESUMO

BACKGROUND: Serum thyroglobulin (Tg) is the most sensitive biomarker for recurrence of differentiated thyroid cancer (DTC). We have assessed the changing pattern of stimulated Tg (sTg) and the clinical course of patients with no structural evidence of disease (NSED), based on imaging studies such as neck ultrasonography (US), fluorodeoxyglucose positron emission tomography, and/or chest computed tomogram (CT). We sought to determine if, in patients with DTC who had been treated with bilateral thyroidectomy and remnant ablation with radioactive iodine, sTg 1 year (sTg1) after initial treatment and repeated sTg measurements, 1-2 years after sTg1, helped predict the long-term outcome with respect to structural recurrence and biochemical remission (BR), which is defined as sTg <1 ng/mL. METHODS: We retrospectively assessed the records of patients with DTC who had been treated with bilateral thyroidectomy and remnant ablation with radioactive iodine between 1995 and 2004. The study included 186 patients who had NSED with sTg1 ≥2 ng/mL and subsequent sTg measurements (sTg2) without additional treatment. Patients were classified into three groups based on their sTg1 measurements: Group A, 2-4.9 ng/mL; Group B, 5-19.9 ng/mL; and Group C, ≥20 ng/mL. Patients were also classified into two groups based on whether sTg2, 1-2 years after sTg1, had decreased by ≥50% (Group 1) or had either decreased by <50% or increased (Group 2). sTg was measured every 1-2 years until structural recurrence or BR. RESULTS: Patients remaining in NSED showed a decrease in serial sTg. Of patients in Groups A, B, and C, 41%, 17%, and 1%, respectively, achieved BR, and there was a significant difference in the BR rate between Groups 1 and 2 (p<0.001). In patients with structural recurrence, serial sTg generally did not decrease from sTg1. There was a significant difference in the recurrence rate among Groups A, B, and C (p=0.005) and between Groups 1 and 2 (p<0.001). CONCLUSIONS: We found that 41% of patients with sTg1 in the range 2-5 ng/mL achieved BR, and that sTg1 and percent change of subsequent sTg were predictive of BR. Repeated sTg measurements are useful for predicting patient prognosis in patients with DTC.


Assuntos
Tireoglobulina/sangue , Neoplasias da Glândula Tireoide/sangue , Adulto , Biomarcadores Tumorais/sangue , Feminino , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Prognóstico , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/terapia , Tireoidectomia
2.
ChemSusChem ; 5(12): 2410-20, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22961747

RESUMO

Acetone was electrocatalytically reduced to isopropanol in a proton-exchange-membrane (PEM) reactor on an unsupported platinum cathode. Protons needed for the reduction were produced on the unsupported Pt-Ru anode from either hydrogen gas or electrolysis of water. The current efficiency (the ratio of current contributing to the desired chemical reaction to the overall current) and reaction rate for acetone conversion increased with increasing temperature or applied voltage for the electrocatalytic acetone/water system. The reaction rate and current efficiency went through a maximum with respect to acetone concentration. The reaction rate for acetone conversion increased with increasing temperature for the electrocatalytic acetone/hydrogen system. Increasing the applied voltage for the electrocatalytic acetone/hydrogen system decreased the current efficiency due to production of hydrogen gas. Results from this study demonstrate the commercial feasibility of using PEM reactors to electrocatalytically reduce biomass-derived oxygenates into renewable fuels and chemicals.


Assuntos
Acetona/química , Fontes de Energia Bioelétrica , Biocombustíveis , Biomassa , Modelos Químicos , Prótons , 2-Propanol/química , Catálise , Técnicas Eletroquímicas , Eletrodos , Desenho de Equipamento , Hidrogênio/química , Membranas Artificiais , Oxirredução , Platina/química , Água/química
3.
Ultrasound Med Biol ; 38(9): 1508-13, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22766122

RESUMO

The aims were to determine the reliability of ultrasound elastography (USE) and the factors related to reliability. One hundred six solid thyroid nodules in 78 consecutive patients were enrolled. Conventional ultrasound examination and USE were performed for each nodule. We evaluated reliability, the factors affecting reliability of USE and the interobserver and intraobserver agreement. We suggest following three criteria as less reliable results: (1) <50% green color in the region of interest box for the thyroid parenchyma; (2) discordance in elasticity scores in the three USE images; and (3) intranodular color signal loss. Consensual reliability of USE was 68% (72/106). Multivariable logistic regression analysis revealed that rim calcification (p = 0.002), a compressive force of ≥3 (p < 0.001) and arterial pulsation (p < 0.001) were significantly associated with reliability of USE. Substantial interobserver (κ = 0.738) and intraobserver agreement were observed in reliable USE results (κ = 0.765). Clinical application of USE should be restricted to the thyroid nodules with reliable results.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Adulto , Idoso , Biópsia por Agulha Fina , Distribuição de Qui-Quadrado , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Estatísticas não Paramétricas , Nódulo da Glândula Tireoide/patologia
4.
Clin Endocrinol (Oxf) ; 77(3): 459-64, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22458627

RESUMO

OBJECTIVE: Anaplastic thyroid carcinoma (ATC) is one of the most aggressive malignancies. Nevertheless, there have been reports that some patients experience long-term survival and those in whom ATCs of small size are often detected. We evaluated the time trend of characteristics of ATC such as size and association with coexistent differentiated thyroid carcinoma (DTC). We also found the characteristics of patients showing long-term survival. DESIGN AND PATIENTS: This is a retrospective observational cohort study from the two major tertiary referral hospitals in Seoul, Korea. Ninety-five patients who had been diagnosed with ATC from 1995 to 2010 were included. We classified them into three groups according to the time of initial diagnosis: group 1 (1995-1999), group 2 (2000-2004) and group 3 (2005-2010). RESULTS: The mean tumour size decreased significantly according to groups; 6·2, 5·5 and 4·0 cm in group 1, 2 and 3, respectively (P = 0·02). The frequency of cases with coexistent DTC increased; 10·3%, 35·1% and 48·3% in group 1, 2 and 3, respectively (P = 0·02). Fifteen of 95 patients survived more than 24 months, and among them, 13 are still alive who underwent curative surgery. Among 15 long-term survivors, nine patients with ATC arising from DTC had ATC tumour portion less than 1 cm. Another five patients with ATC without coexistent DTC had relatively small-sized tumours (1·0-4·0 cm). CONCLUSION: The tumour size of ATC decreased, and cases with coexistent DTC increased over the last two decades. We found that patients with ATC showing long-term survival are those who had atypical presentations such as anaplastic transformation in early stage of DTC or small size of tumours without coexistent DTC.


Assuntos
Carcinoma/patologia , Neoplasias da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/cirurgia , Carcinoma/terapia , Diferenciação Celular , Estudos de Coortes , Terapia Combinada , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/terapia , Tireoidectomia , Fatores de Tempo , Adulto Jovem
5.
Thyroid ; 21(12): 1385-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22066478

RESUMO

BACKGROUND: Traumatic neuroma can be confused with a metastatic lymph node after neck dissection for malignancy, thereby increasing patient anxiety and necessitating fine needle aspiration (FNA). To date, however, there have been no reports showing a direct ultrasonographic (US) sign of traumatic neuroma that could help distinguish it from a metastatic lymph node after neck dissection. Here, we describe a patient with traumatic neuroma who showed a direct US sign after total thyroidectomy with modified radical neck dissection (MRND). SUMMARY: A 61-year-old man who had undergone total thyroidectomy with bilateral MRND for papillary thyroid carcinoma was found to have an oval-shaped nodule in his right lateral neck by US examination, which was first suspected of being a metastatic lymph node. However, when the position of the US transducer was changed to the oblique plane, a thin, cord-like, hypoechoic structure was found to be connected to the nodule. This structure passed between the longus capitis and scalenus medius muscles in an upward direction, and was ultimately located in the groove of the right transverse process of the C4 vertebra. Based on this anatomic relation, we concluded that the nodule was a traumatic neuroma and did not perform an unnecessary FNA. CONCLUSIONS: The detection of a mass in the line of the transected nerve may be a direct US indication of traumatic neuroma after neck dissection.


Assuntos
Plexo Cervical/diagnóstico por imagem , Esvaziamento Cervical/efeitos adversos , Neuroma/diagnóstico por imagem , Traumatismos dos Nervos Periféricos/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Carcinoma , Carcinoma Papilar , Plexo Cervical/lesões , Diagnóstico Diferencial , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neuroma/etiologia , Traumatismos dos Nervos Periféricos/etiologia , Valor Preditivo dos Testes , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/patologia , Tomografia Computadorizada por Raios X , Ultrassonografia
6.
Nano Lett ; 11(9): 3656-62, 2011 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-21859120

RESUMO

Here, we report Si pillar and well arrays as tailored electrode materials for advanced Li ion storage devices. The well-ordered and periodic morphologies were formed on a Si electrode thin film via laser interference lithography followed by a dry etch process. Two different patterns of negatively or positively carved Si electrodes exhibited highly improved cycle performance as a consequence of the enlarged surface area and the nanoscale pattern effects. The Si well arrays showed the highest energy density, rate capability, and cycling retention among the prepared Si electrodes. This tailored electrode platform demonstrates that these design principles could be applied to future developments in Si electrodes.

7.
Nanoscale Res Lett ; 6(1): 292, 2011 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-21711839

RESUMO

We prepared a composite electrode structure consisting of copper nanofiber-networked cobalt oxide (CuNFs@CoOx). The copper nanofibers (CuNFs) were fabricated on a substrate with formation of a network structure, which may have potential for improving electron percolation and retarding film deformation during the discharging/charging process over the electroactive cobalt oxide. Compared to bare CoOxthin-film (CoOxTF) electrodes, the CuNFs@CoOxelectrodes exhibited a significant enhancement of rate performance by at least six-fold at an input current density of 3C-rate. Such enhanced Li-ion storage performance may be associated with modified electrode structure at the nanoscale, improved charge transfer, and facile stress relaxation from the embedded CuNF network. Consequently, the CuNFs@CoOxcomposite structure demonstrated here can be used as a promising high-performance electrode for Li-ion batteries.

8.
J Nanosci Nanotechnol ; 10(12): 8199-203, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21121316

RESUMO

We have one-pot fabricated Si-based nanocomposite electrodes containing Ag nano-dots for thin-film Li rechargeable batteries by a co-sputtering method. The structural and electrochemical properties of the Si/Ag nanocomposite electrodes are investigated via transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and cycler. The TEM and XRD results show that crystalline Ag nano-dots (approximately 5-9 in size) are well-dispersed within an amorpohous Si matrix. It is shown that the Si/Ag nanocomposite electrode shows much better structural stability than the Si only sample. It is also shown that the Si/Ag nanocomposite electrode shows superior capacity retention compared to the Si only electrode. The results indicate that the presence of the Ag nano-dots is important minimizing the formation of cracks in the electrode, so leading to the better life-time for thin-film Li rechargeable batteries.

9.
ACS Nano ; 4(4): 1829-36, 2010 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-20235570

RESUMO

A novel and effective methodology to control the diameters of semiconductor nanowires is reported through a versatile contact-printing method for obtaining size-controlled nanocatalysts by size-tunable carbon-based nanometer stamps. Vertically aligned carbon nanopost arrays, derived from nanoporous alumina templates, are used as the nanoscale stamps for printing of catalyst nanoparticles. The diameter of the carbon nanopost can be engineered by adjusting the pore dimension of the templates. Over the contact-printed Au nanodots in a uniform size distribution, semiconductor SnO2 nanowires are grown via a vapor-liquid-solid growth mechanism. Consequently, a direct dimension correspondence is achieved between the carbon nanopost stamp, the printed Au catalyst, and the finally obtained SnO2 nanowires. A model example of the diameter-dependent electrical properties of the semiconductor nanowires is successfully demonstrated in this work by applying three diameter-controlled SnO2 nanowires to nanowire field effect transistors.

10.
Nanotechnology ; 19(36): 365305, 2008 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-21828870

RESUMO

A nanoscale tubular carbon structure array was demonstrated as a mold for nanoimprint lithography (NIL), in which a vertically formed and hexagonally aligned nanoscale tubular carbon array was fabricated through carbon growth inside an anodic aluminum oxide (AAO) nanotemplate, followed by controlled chemical etching of the AAO layer. High density (over 10(10) cm(-2)) of the nanoscale carbon pillars with their controlled diameters and protruded lengths was inversely replicated onto a UV-curable resist for the first time using the imprinting lithography technique.

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