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1.
World J Gastrointest Oncol ; 16(3): 933-944, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38577453

RESUMO

BACKGROUND: Transanal endoscopic intersphincteric resection (ISR) surgery currently lacks sufficient clinical research and reporting. AIM: To investigate the clinical effectiveness of transanal endoscopic ISR, in order to promote the clinical application and development of this technique. METHODS: This study utilized a retrospective case series design. Clinical and pathological data of patients with lower rectal cancer who underwent transanal endoscopic ISR at the First Affiliated Hospital of Xiamen University between May 2018 and May 2023 were included. All patients underwent transanal endoscopic ISR as the surgical approach. We conducted this study to determine the perioperative recovery status, postoperative complications, and pathological specimen characteristics of this group of patients. RESULTS: This study included 45 eligible patients, with no perioperative mortalities. The overall incidence of early complications was 22.22%, with a rate of 4.44% for Clavien-Dindo grade ≥ III events. Two patients (4.4%) developed anastomotic leakage after surgery, including one case of grade A and one case of grade B. Postoperative pathological examination confirmed negative circumferential resection margins and distal resection margins in all patients. The mean distance between the tumor lower margin and distal resection margin was found to be 2.30 ± 0.62 cm. The transanal endoscopic ISR procedure consistently yielded high quality pathological specimens. CONCLUSION: Transanal endoscopic ISR is safe, feasible, and provides a clear anatomical view. It is associated with a low incidence of postoperative complications and favorable pathological outcomes, making it worth further research and application.

2.
World J Gastroenterol ; 30(1): 79-90, 2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38293327

RESUMO

BACKGROUND: Laparoscopic radical gastrectomy is widely used, and perioperative complications have become a highly concerned issue. AIM: To develop a predictive model for complications in laparoscopic radical gastrectomy for gastric cancer to better predict the likelihood of complications in gastric cancer patients within 30 days after surgery, guide perioperative treatment strategies for gastric cancer patients, and prevent serious complications. METHODS: In total, 998 patients who underwent laparoscopic radical gastrectomy for gastric cancer at 16 Chinese medical centers were included in the training group for the complication model, and 398 patients were included in the validation group. The clinicopathological data and 30-d postoperative complications of gastric cancer patients were collected. Three machine learning methods, lasso regression, random forest, and artificial neural networks, were used to construct postoperative complication prediction models for laparoscopic distal gastrectomy and laparoscopic total gastrectomy, and their prediction efficacy and accuracy were evaluated. RESULTS: The constructed complication model, particularly the random forest model, could better predict serious complications in gastric cancer patients undergoing laparoscopic radical gastrectomy. It exhibited stable performance in external validation and is worthy of further promotion in more centers. CONCLUSION: Using the risk factors identified in multicenter datasets, highly sensitive risk prediction models for complications following laparoscopic radical gastrectomy were established. We hope to facilitate the diagnosis and treatment of preoperative and postoperative decision-making by using these models.


Assuntos
Laparoscopia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Estudos Retrospectivos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Laparoscopia/efeitos adversos , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Resultado do Tratamento
3.
Nanomaterials (Basel) ; 12(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36500879

RESUMO

In this work, the atomic level doping of Sn into Ga2O3 films was successfully deposited by using a plasma-enhanced atomic layer deposition method. Here, we systematically studied the changes in the chemical state, microstructure evolution, optical properties, energy band alignment, and electrical properties for various configurations of the Sn-doped Ga2O3 films. The results indicated that all the films have high transparency with an average transmittance of above 90% over ultraviolet and visible light wavelengths. X-ray reflectivity and spectroscopic ellipsometry measurement indicated that the Sn doping level affects the density, refractive index, and extinction coefficient. In particular, the chemical microstructure and energy band structure for the Sn-doped Ga2O3 films were analyzed and discussed in detail. With an increase in the Sn content, the ratio of Sn-O bonding increases, but by contrast, the proportion of the oxygen vacancies decreases. The reduction in the oxygen vacancy content leads to an increase in the valence band maximum, but the energy bandgap decreases from 4.73 to 4.31 eV. Moreover, with the increase in Sn content, the breakdown mode transformed the hard breakdown into the soft breakdown. The C-V characteristics proved that the Sn-doped Ga2O3 films have large permittivity. These studies offer a foundation and a systematical analysis for assisting the design and application of Ga2O3 film-based transparent devices.

4.
J Synchrotron Radiat ; 21(Pt 3): 561-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24763646

RESUMO

A novel correction method for self-absorption effects is proposed for extended X-ray absorption fine structure (EXAFS) detected in the fluorescence mode on multilayer samples. The effects of refraction and multiple reflection at the interfaces are fully considered in this correction method. The correction is performed in k-space before any further data analysis, and it can be applied to single-layer or multilayer samples with flat surfaces and without thickness limit when the model parameters for the samples are known. The validity of this method is verified by the fluorescence EXAFS data collected for a Cr/C multilayer sample measured at different experimental geometries.

5.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 27(5): 483-6, 2009 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-19927714

RESUMO

OBJECTIVE: To evaluate the effect of nicotine on cell proliferation. METHODS: The cells were cultured with DMEM medium containing 10% fetal bovine serum with 0, 1 x 10(-4) mol x L(-1), and 1 x 10(-3) mol x L(-1) nicotine for up to 3, 5, 7, 10, 14 days. The cell proliferation was evaluated by MTT. The alkaline phosphatase (ALP) activity was estimated by PNPP. The expression of collagen type I (COL1) and osteocalcin (OCN) were estimated by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Nicotine suppressed the cell proliferation. ALP activity increased to peak on 10 days in control and 1 x 10(-4) mol x L(-1) nicotine. COL1 expression increased to peak on 10 days in control and 1 x 10(-4) mol x L(-1) nicotine, but there was decreased to the minimum on 10 days and increased on 14 days in 1 x 10(-3) mol x L(-1) nicotine. OCN expression increased to peak on 10 days in control, and increased in 1 x 10(-4) mol x L(-1) nicontine from 3 days to 14 days, but there wasn't significant change in 1 x 10(-3) mol x L(-1) nicontine. CONCLUSION: Nicotine suppresses osteogenesis through a decrease in ALP and COL1 production by osteoblasts.


Assuntos
Fosfatase Alcalina , Nicotina , Neoplasias Ósseas , Linhagem Celular , Proliferação de Células , Colágeno Tipo I , Humanos , Osteoblastos , Osteocalcina , Osteogênese , Osteossarcoma
6.
Opt Express ; 17(4): 2586-99, 2009 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-19219162

RESUMO

A new method of designing soft X-ray transmission multilayer polarizer for use at a single wavelength using a merit function has been eveloped. A merit function of product of p-transmittance throughput and logarithm of transmittance polarization ratio was chosen. Characteristics of Mo/Si multilayer calculated using the merit function at 13.0 nm have been compared with those calculated using the traditional method by the present authors and those reported so far. The merit function has given the most optimal results of throughput of 30.0% and polarization ratio of 202. The polarizers of much higher polarization ratio or much larger p-transmittance can be designed by choosing the number of layers and optimizing the thickness of each layer to maximize the merit function. Using this method, the roughness effect has been studied on Mo/Si and La/B multilayer polarizers at 13.0 nm and 6.7 nm, respectively. It was found that the influence of roughness is crucial in shorter wavelength region.


Assuntos
Desenho Assistido por Computador , Microscopia de Polarização/instrumentação , Intensificação de Imagem Radiográfica/instrumentação , Refratometria/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Microscopia de Polarização/métodos , Refratometria/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Space Med Med Eng (Beijing) ; 18(1): 37-40, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15852548

RESUMO

OBJECTIVE: To develop a ground-based experimental prototype of space vegetable-cultivating facility (GEPSVF), so as to solve the main key techniques related to higher plant cultivation in space environmental conditions, and to further lay a foundation for future development and application of the prototype of space vegetable-growing facility. METHOD: Based on detailed demonstration and design of technique plan, the blueprint design and machining of components, whole facility installment, debugging, trial operations and verification experiments were done. RESULT: The parameters in the growing chamber such as temperature, relative humidity, wind velocity, total pressure, O2 partial pressure, CO2 partial pressure and water content of the growing media were totally and effectively controlled; the light source was electronic fluorescent lamp; the average vegetable-producing output reached 60 g (fresh weight) d-1. CONCLUSION: The prototype could operate stably; its actual performance indexes achieved the expected ones basically; some of its operating principles can adapt to space microgravity condition. Therefore, the prototype is a good beginning for future development of space vegetable-producing facilities.


Assuntos
Sistemas Ecológicos Fechados , Hidroponia/instrumentação , Voo Espacial/instrumentação , Ausência de Peso , Pressão Atmosférica , Dióxido de Carbono , Desenho de Equipamento , Estudos de Avaliação como Assunto , Arquitetura de Instituições de Saúde , Umidade , Hidroponia/métodos , Lactuca , Sistemas de Manutenção da Vida/instrumentação , Oxigênio , Pressão Parcial , Temperatura , Água , Vento
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