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1.
Front Oncol ; 14: 1304793, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38380361

RESUMEN

Purpose: To investigate the value of quantitative longitudinal relaxation time (T1), transverse relaxation time (T2), and proton density (PD) maps derived from synthetic magnetic resonance imaging (MRI) for evaluating the status of lymphovascular space invasion (LVSI) in cervical squamous cell carcinoma (CSCC) without lymph node metastasis (LNM). Material and methods: Patients with suspected cervical cancer who visited our hospital from May 2020 to March 2023 were collected. All patients underwent preoperative MRI, including routine sequences and synthetic MRI. Patients with pathologically confirmed CSCC without lymphatic metastasis were included in this study. The subjects were divided into negative- and positive-LVSI groups based on the status of LVSI. Quantitative parameters of T1, T2, and PD values derived from synthetic MRI were compared between the two groups using independent samples t-test. Receiver operating characteristic curves were used to determine the diagnostic efficacy of the parameters. Results: 59 patients were enrolled in this study and were classified as positive (n = 32) and negative LVSI groups (n = 27). T1 and T2 values showed significant differences in differentiating negative-LVSI from positive-LVSI CSCC (1307.39 ± 122.02 vs. 1193.03 ± 107.86, P<0.0001; 88.42 ± 7.24 vs. 80.99 ± 5.50, P<0.0001, respectively). The area under the curve (AUC) for T1, T2 values and a combination of T1 and T2 values were 0.756, 0.799, 0.834 respectively, and there is no statistically significant difference in the diagnostic efficacy between individual and combined diagnosis of each parameter. Conclusions: Quantitative parameters derived from synthetic MRI can be used to evaluate the LVSI status in patients with CSCC without LNM.

2.
ACS Omega ; 8(7): 6854-6859, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36844594

RESUMEN

Herein, we report that under mild and transition-metal-free conditions an unprecedented and practical SN2' reaction of Morita-Baylis-Hillman adducts with isocyanoacetates takes place in a stereo- and regiospecific manner. This reaction which tolerates a wide variety of functionalities delivers transformable α-allylated isocyanoacetates in high efficiencies. Preliminary studies on the asymmetric version of this reaction indicate that ZnEt2/chiral amino alcohol combinations are an asymmetric catalytic system for this transformation, giving an enantioenriched α-allylated isocyanoacetate with a chiral quaternary carbon in a high yield.

3.
Sci Rep ; 13(1): 17978, 2023 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-37864025

RESUMEN

To evaluate and compare the performance of synthetic magnetic resonance imaging (SyMRI) in classifying benign and malignant breast lesions and predicting the expression status of immunohistochemistry (IHC) markers. We retrospectively analysed 121 patients with breast lesions who underwent dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and SyMRI before surgery in our hospital. DCE-MRI was used to assess the lesions, and then regions of interest (ROIs) were outlined on SyMRI (before and after enhancement), and apparent diffusion coefficient (ADC) maps to obtain quantitative values. After being grouped according to benign and malignant status, the malignant lesions were divided into high and low expression groups according to the expression status of IHC markers. Logistic regression was used to analyse the differences in independent variables between groups. The performance of the modalities in classification and prediction was evaluated by receiver operating characteristic (ROC) curves. In total, 57 of 121 lesions were benign, the other 64 were malignant, and 56 malignant lesions performed immunohistochemical staining. Quantitative values from proton density-weighted imaging prior to an injection of the contrast agent (PD-Pre) and T2-weighted imaging (T2WI) after the injection (T2-Gd), as well as its standard deviation (SD of T2-Gd), were valuable SyMRI parameters for the classification of benign and malignant breast lesions, but the performance of SyMRI (area under the curve, AUC = 0.716) was not as good as that of ADC values (AUC = 0.853). However, ADC values could not predict the expression status of breast cancer markers, for which SyMRI had excellent performance. The AUCs of androgen receptor (AR), estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2), p53 and Ki-67 were 0.687, 0.890, 0.852, 0.746, 0.813 and 0.774, respectively. SyMRI had certain value in distinguishing between benign and malignant breast lesions, and ADC values were still the ideal method. However, to predict the expression status of IHC markers, SyMRI had an incomparable value compared with ADC values.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Estudios Retrospectivos , Mama/patología , Imagen por Resonancia Magnética/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Curva ROC , Medios de Contraste , Diagnóstico Diferencial , Sensibilidad y Especificidad
4.
Sci Prog ; 103(4): 36850420961610, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33073721

RESUMEN

Glass fiber-reinforced plastics (GFRP) based on polymer materials are widely used in lightweight impac-resistant structure design. In the process of design and development, it is very important to clarify the mechanical behavior under dynamic load to improve the product performance. Therefore, in this paper, Quasi-stati and dynamic compression behaviors of unidirectional continuous glass fiber-reinforced vinyl ester (GF/VE) composites with five kinds of fiber contents in the fiber direction were measured by an electro-hydraulic servo experiment system and a split Hopkinson pressure bar, and damage evolution of the material is analyzed by observing the microstructure of the cross section of the material. Results show that: The content of glass fiber affects the wettability between fiber and matrix, and the failure mechanism of material at high strain rate; Under quasi-static conditions, higher glass fiber content yields greater failure strength; Under dynamic conditions, as glass fiber content increases, toughness decreases, and the peak stress first increases and then decreases. Finally, the nonlinear viscoelastic constitutive model with damage evolution is derived, which can be used to predict the impact resistance of new composite structures in the product development and design stage and reduce the development cycle.

5.
Zhonghua Liu Xing Bing Xue Za Zhi ; 30(10): 1043-6, 2009 Oct.
Artículo en Zh | MEDLINE | ID: mdl-20193386

RESUMEN

OBJECTIVE: To investigate the epidemiological features of patients with nosocomial invasive fungal infection. METHODS: Fungi in blood were identified by BacT ALERT 3D, other clinical samples were cultured by Sabouraud's dextrose agar (SDA) medium. Candidas were isolated and identified by CHRO Magar candida color medium. Fungus-cultured positive cases from Jan. 2004 to Nov. 2007 were analyzed on items as patients' age, underlying disease, sample, strain, and species distribution. All statistical analyses were carried out by SPSS 13.0. RESULTS: The overall incidence rate of invasive fungal infections was 4.12%. The average age of patients was 7 - 96 with most patients were male, with geriatric problems and different kinds of underlying diseases. Lower respiratory tract infection was the most frequent infection site, followed by urinary tract, gastrointestinal tract. The main pathogens of invasive fungal infections were Candidas (93.80%). Strains of Candida albicans were the most frequent organisms which accounted for 67.29% of all the isolates. Mould fungus infections accounted for only 6.20%. During the 4 years of observation, the detection rate of fungi, specimen sources and the distribution of species and compartment were different with significant differences (P < 0.0083). CONCLUSION: The epidemiological properties such as the source of specimen, the distribution of species and composition sections of invasive fungal infections were changing. Candida spp. were still the main pathogens of invasive fungal infections but the sections of fungi changed. The incidence of Aspergillus infections had been increasing recently.


Asunto(s)
Infección Hospitalaria/epidemiología , Micosis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Candida/aislamiento & purificación , Niño , China/epidemiología , Infección Hospitalaria/microbiología , Femenino , Tracto Gastrointestinal/microbiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Micosis/microbiología , Infecciones del Sistema Respiratorio/microbiología , Factores Sexuales , Infecciones Urinarias/microbiología , Adulto Joven
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