Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Clin Respir J ; 18(8): e13817, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39118303

RESUMEN

Lung squamous cell carcinoma (LUSC) is characterized by a high rate of metastasis and recurrence, leading to a poor prognosis for affected patients. Intestinal metastasis of LUSC is a rare clinical occurrence. Treatment options for LUSC patients with intestinal metastasis are limited, and no standard therapy guidelines exist for managing these cases. In this review, we discuss the clinical features, diagnosis, and treatment of LUSC patients with intestinal metastasis and present a rare case of LUSC with intestinal metastasis. We describe a patient who presented with a severe cough and chest pain and diagnosed with LUSC and bone tumor. Initially, the primary LUSC and bone tumor were controlled with standard treatments. However, the primary LUSC reoccurred shortly after treatment, this time with intestinal metastasis, for which effective treatments are lacking. Our observation from the case suggests that LUSC metastasizing to intestinal tract is associated with a poorer prognosis.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/patología , Carcinoma de Células Escamosas/secundario , Carcinoma de Células Escamosas/patología , Masculino , Neoplasias Intestinales/secundario , Neoplasias Intestinales/patología , Pronóstico , Tomografía Computarizada por Rayos X/métodos , Persona de Mediana Edad , Resultado Fatal , Anciano , Neoplasias Óseas/secundario
2.
Materials (Basel) ; 17(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38611977

RESUMEN

In this study, the microstructural evolution of a Ti-15Mo medical alloy was investigated, when the in situ cyclic tensile strain had 2% amplitude and the tension-compression cyclic deformation had 1%, 2%, and 3% amplitude. The Vickers hardness and wear resistance of the alloy were also optimized due to the grain-refining effect after cyclic deformation and annealing. The twinning-induced plasticity (TWIP) was considered the main deformation mechanism of the Ti-15Mo alloy during the tensile-compressive cycle deformation with suitable strain amplitude. The {332}<113> twins and boundaries were the main contributors to the grain refinement. The optimal microstructure, hardness, and wear resistance were obtained in the alloy deformed by tension-compression cyclic strain with a 3% strain amplitude. The wear resistance of the annealed alloy in Hank's solution was excellent in contrast to the original Ti-15Mo alloy due to its reasonable microstructure and hardness. It is clear that abundant twins were formed and retained in the coarse grains of the original alloy after cyclic deformation and annealing, which provided the expected refined grains and performance.

3.
J Card Surg ; 37(7): 2145-2148, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35445760

RESUMEN

BACKGROUND: Anomalous aortic origin of the coronary artery (AAOCA) refers to a congenital abnormality of the origin and/or course of a coronary artery that arises from the aorta. It can be classified according to the sinus from which the coronary artery arises. The most common type is an anomalous origin of the right coronary artery. CASE PRESENTATION: Herein, we report a 7-year-old male that was diagnosed with AAOCA. Although the patient had not complained of obvious symptoms before the onset, echocardiography showed that the left coronary artery originated from the noncoronary sinus at an anatomical location. CONCLUSION: AAOCA is a rare congenital disease that often causes a sudden death in young athletes. Originating from the noncoronary sinus at the level of the sinotubular junction in the anomalous origin of the left coronary artery is even more rare which is presented in this case. Surgical intervention should be actively performed if the patient has symptoms or if the anatomy is complex.


Asunto(s)
Anomalías de los Vasos Coronarios , Aorta , Niño , Anomalías de los Vasos Coronarios/diagnóstico por imagen , Anomalías de los Vasos Coronarios/cirugía , Humanos , Masculino
4.
Materials (Basel) ; 13(16)2020 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-32823534

RESUMEN

We studied the effect of Cu addition on the hardness of ultra-low carbon steels heat treated with different cooling rates using thermal simulation techniques. The microstructural evolution, Cu precipitation behaviors, variations of Vickers hardness and nano-hardness are comparatively studied for Cu-free and Cu-bearing steels. The microstructure transforms from ferritic structure to ferritic + bainitic structure as a function of cooling rate for the two steels. Interphase precipitation occurs in association with the formation of ferritic structure at slower cooling rates of 0.05 and 0.2 °C/s. Coarsening of Cu precipitates occurs at 0.05 °C/s, leading to lower precipitation strengthening. As the cooling rate increases to 0.2 °C/s, the interphase and dispersive precipitation strengthening effects are increased by 63.9 and 50.0 MPa, respectively. Cu precipitation is partially constrained at cooling rate of 5 °C/s, resulting in poor nano-hardness and Young's Modulus. In comparison with Cu-free steel, the peak Vickers hardness, nano-hardness and Young's Modulus are increased by 56 HV, 0.61 GPa and 55.5 GPa at a cooling rate of 0.2 °C/s, respectively. These values are apparently higher than those of Cu-free steel, indicating that Cu addition in steels can effectively strengthen the matrix.

5.
Sci Rep ; 9(1): 17628, 2019 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-31772260

RESUMEN

The activation energy of the ß â†’ α/ω phase transformation increased monotonously with the application of a continuous heating process to a Ti-15Mo-2.7Nb-3Al-0.2Si alloy. Precipitation behaviour of the alloy aged at different temperatures were analysed with scanning electron microscopy, electron backscattered diffraction and transmission electron microscopy. Selected-area diffraction patterns of the ω, ω/α and α phases in the alloy aged at different temperatures indicated that the type of phase transformation was influenced by the precipitation process. Precipitate-free zones in the alloy aged at 450 °C for 8 h were harmful to the mechanical performance. Fine α precipitates with an obvious texture were obtained in the alloy aged at 500 °C. A good combination of tensile properties with an ultimate tensile strength of 1310 MPa and an elongation of 13.5% were obtained due to the expected microstructure and texture of the precipitates that transformed in the specimen when it was aged at 500 °C for 8 h. The size of the precipitates increased with increasing aging temperature. Furthermore, the amount of precipitates and their degree of texture decreased substantially in the alloy aged at 600 °C. The investigation of the tensile properties and fractures also revealed a correlation between the mechanical properties and precipitation behaviour in the Ti-15Mo-2.7Nb-3Al-0.2Si alloy aged at different temperatures.

6.
Materials (Basel) ; 12(10)2019 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-31126013

RESUMEN

The effect of heat treatment on the microstructures and mechanical properties of a novel ß-solidifying Ti-43Al-2Cr-2Mn-0.2Y alloy was investigated. A fully lamellar (FL) microstructure with a colony size of about 100 µm was obtained by heat treatment at 1320 °C/10 min/furnace cooling (FC). A duplex (DP) microstructure with globular γ grains and γ/α2 lamellae was obtained by heat treatment at 1250 °C/4 h/FC. The residual hard-brittle ß0 phase was also eliminated after heat treatment. The mechanical properties of the ß-solidifying TiAl alloy depended closely on the heat treatment. The FL alloy had better fracture toughness, and the fracture toughness (KIC) value was 24.15 MPa·m1/2. The DP alloy exhibited better ductility, and the room temperature (RT) elongation of the alloy could reach 1%. The elongation of the alloy with different microstructures sharply increased when the temperature increased from 700 to 750 °C, indicating that the microstructure had no effect on the ductile-brittle transition temperature of the ß-solidifying TiAl alloy. The fracture morphologies of different tensile specimens were observed. Interlamellar and translamellar fractures were the main fracture features of the FL alloy. Intergranular, translamellar, and interlamellar fractures were the main fracture features of the DP alloy.

7.
Materials (Basel) ; 12(9)2019 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-31035383

RESUMEN

This study systematically investigated the influence of multi-directional forging (MDF) on the microstructural evolution, hot deformation behavior, and tensile properties of a ß-solidifying TiAl alloy. The initial lamellar microstructure of an as-cast alloy was remarkably refined and homogenized by three-step MDF. High temperatures and multi-pass deformations were conducive to the decomposition of lamellae. A crack-free billet was obtained through three-step MDF, with a deformation temperature of 1250 °C and a forging speed of 0.1 mm/s, indicating that MDF can be applied to ß-solidifying TiAl alloys by the proper control of the alloy composition and process parameters. Microstructural observation showed that the billet mainly consists of fine and equiaxed γ grains and a small amount of ß phase. The tensile properties of the multi-directional forged alloy were also significantly improved, due to microstructure refinement. The ultimate tensile strength (UTS) and elongation (δ) at room temperature were 689.4 MPa, and 0.83%, respectively. The alloy exhibits excellent ductility at 700 °C. When the temperature was increased to 700 °C, the UTS decreased to 556 MPa and δ increased to 5.98%, indicating that the alloy exhibits excellent ductility at 700 °C. As the temperature further increased to 750 °C, δ dramatically increased to 46.65%, indicating that the ductile-brittle transition temperature of the alloy is between 700 °C and 750 °C.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA