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1.
Int J Clin Oncol ; 24(6): 666-676, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30788672

RESUMO

BACKGROUND: Brain metastasis is a rare event in patients with hepatocellular carcinoma (HCC). This retrospective study aimed to identify the prognostic factors and determine the outcomes of patients with brain metastases from HCC. METHODS: About 86 patients with brain metastases (0.6%) from HCC were identified from two institutions; of them, 32 underwent tumor-removing surgery or stereotactic radiosurgery (SRS) with or without adjuvant whole brain radiotherapy (WBRT) (group 1), 30 had WBRT alone (group 2), and 24 received conservative treatment (group 3). Estimates for overall survival (OS) after brain metastases were determined, and clinical prognostic factors were identified. RESULTS: The median OS after development of brain metastases was 50 days. About 75 (87.2%) patients had lung metastases at the time of brain metastasis diagnosis. Group 1 showed better OS, followed by group 2 and group 3, sequentially (p < 0.001). Univariate analyses showed that treatment with curative intent (surgery or SRS), Child-Pugh class A, alpha-fetoprotein level < 400 ng/ml, and recursive partitioning analysis classification I or II were associated with improved survival (p < 0.001, 0.002, 0.029, and 0.012, respectively). Multivariate analysis showed that treatment with curative intent and Child-Pugh class A was associated with improved OS (p < 0.001 and 0.009, respectively). CONCLUSION: Although the overall prognosis of patients with brain metastases from HCC is extremely poor, patients actively treated with surgery or radiosurgery have prolonged survival, suggesting that interventions to control intracranial disease are important in these patients.


Assuntos
Neoplasias Encefálicas/mortalidade , Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/mortalidade , Radiocirurgia/mortalidade , Adulto , Idoso , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
2.
Opt Express ; 18(10): 9747-54, 2010 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-20588825

RESUMO

A novel method for auto-correction of fiber optic distributed temperature sensor using anti-Stokes Raman back-scattering and its reflected signal is presented. This method processes two parts of measured signal. One part is the normal back scattered anti-Stokes signal and the other part is the reflected signal which eliminate not only the effect of local losses due to the micro-bending or damages on fiber but also the differential attenuation. Because the beams of the same wavelength are used to cancel out the local variance in transmission medium there is no differential attenuation inherently. The auto correction concept was verified by the bending experiment on different bending points.


Assuntos
Artefatos , Tecnologia de Fibra Óptica/instrumentação , Refratometria/instrumentação , Análise Espectral Raman/instrumentação , Termômetros , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento , Retroalimentação , Luz , Espalhamento de Radiação
3.
J Colloid Interface Sci ; 247(1): 231-45, 2002 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16290460

RESUMO

Interfacial and microfailure properties of carbon fiber/epoxy composites were evaluated using both tensile fragmentation and compressive Broutman tests with an aid of acoustic emission (AE). A monomeric and two polymeric coupling agents were applied via the electrodeposition (ED) and the dipping applications. A monomeric and a polymeric coupling agent showed significant and comparable improvements in interfacial shear strength (IFSS) compared to the untreated case under both tensile and compressive tests. Typical microfailure modes including cone-shaped fiber break, matrix cracking, and partial interlayer failure were observed under tension, whereas the diagonal slipped failure at both ends of the fractured fiber exhibited under compression. Adsorption and shear displacement mechanisms at the interface were described in terms of electrical attraction and primary and secondary bonding forces. For both the untreated and the treated cases AE distributions were separated well in tension, whereas AE distributions were rather closely overlapped in compression. It might be because of the difference in molecular failure energies and failure mechanisms between tension and compression. The maximum AE voltage for the waveform of either carbon or large-diameter basalt fiber breakages in tension exhibited much larger than that in compression. AE could provide more likely the quantitative information on the interfacial adhesion and microfailure.

4.
Ultrasonics ; 40(1-8): 803-7, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12160048

RESUMO

A high powered Q-switched Nd:YAG laser was used to excite the surface waves, and an optical fiber sensor was used to detect the out-of-plane displacements due to the propagating waves. This sensor is based on the fiber optic Sagnac interferometer, which has the path-matched configuration and does not require active stabilization. Quadrature phase bias between two interfering laser beams in the Sagnac loop is applied by controlling the birefringence in an optical path using a fiber polarization controller. A stable quadrature phase bias can be confirmed by observing the interferometer output according to the change of phase bias. Additional signal processing is not needed for the detection of ultrasonic waves using the Sagnac interferometer. The performance of the fiber optic Sagnac interferometer was investigated, and laser-generated surface wave signals were detected using this fiber optic sensor. The developed fiber optic sensor configured in this study is very simple and is effective for non-contact detection of ultrasonic waves.

5.
Knee Surg Sports Traumatol Arthrosc ; 15(6): 781-5, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17024477

RESUMO

We report a case of en bloc avulsion fracture of tibial tuberosity and Gerdy's tubercle, which has never been reported. A 14-year-old boy suffered from an acute pain in his left knee during running just before a jump. Simple radiographs showed an avulsion of the tibial tuberosity. On CT scans, the fractured fragment was attached not only to patellar tendon but also to iliotibial band (ITB) via Gerdy's tubercle. MRI evaluation revealed no intra-articular associated pathology. Open reduction and internal fixation with three cannulated screws were performed under lateral parapatellar approach to expose both the tibial tuberosity with patellar tendon and Gerdy's tubercle with ITB. At postoperative 1 year, he could walk, run, squat, and complained of no difficulty in activities on daily living with full range-of-motion of the knee. Radiographs showed well-healed fracture in situ. Gradually, he returned to sports activity. We believe that the injury was caused by the dynamic pull of quadriceps muscle via patellar tendon onto tibial tuberosity and the mostly static pull of ITB onto Gerdy's tubercle, both of which took a part in the fracture of the anterolateral portion of the unfused epiphysis of proximal tibia. The pes anserinus attaching on the anteromedial metaphysis of proximal tibia might exert the opposing deforming force. Preoperative planning including the determination of the extent of fracture and recognition of concomitant injury is a prerequisite for appropriate treatment.


Assuntos
Basquetebol/lesões , Traumatismos do Joelho/diagnóstico , Fraturas da Tíbia/diagnóstico , Adolescente , Fixação Interna de Fraturas , Humanos , Traumatismos do Joelho/etiologia , Traumatismos do Joelho/cirurgia , Masculino , Fraturas da Tíbia/etiologia , Fraturas da Tíbia/cirurgia
6.
J Colloid Interface Sci ; 237(1): 80-90, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11334518

RESUMO

Interfacial adhesion and nondestructive behavior of the electrodeposited (ED) carbon fiber reinforced composites were evaluated using the electro-micromechanical technique and acoustic emission (AE). Interfacial shear strength (IFSS) of the ED carbon fiber/epoxy composites was higher than that of the untreated case. This might be expected because of the possible chemical and hydrogen bonding based on an electrically adsorbed polymeric interlayer. Logarithmic electrical resistivity of the untreated single-carbon fiber composite increased suddenly to infinity when the fiber fracture occurred, whereas that of the ED composite increased relatively broadly up to infinity. This may be due to the retarded fracture time as a result of the enhanced IFSS. In single- and 10-carbon fiber composites, the number of AE signals coming from the interlayer failure of the ED carbon fiber composite was much larger than that of the untreated composite. As the number of each first fiber fracture increased in the 10-carbon fiber composite, the electrical resistivity increased stepwise, and the slope of logarithmic electrical resistance increased. In the three-graphite filament composite with a narrow 1 time inter-filament distance, the total numbers of the filament fracture and the IFSS were smaller than those of the wider 5 times case. This might be because the interacting fracture energy caused by a filament break could affect the adjacent filaments. Copyright 2001 Academic Press.

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