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1.
Acta Radiol ; 64(6): 2211-2216, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37128160

RESUMO

BACKGROUND: Central catheter-related thrombosis (CRT) is the most common catheter-related complication in patients with end-stage renal disease (ESRD) but is often underappreciated and misdiagnosed by radiologist. PURPOSE: To find the computed tomography angiography (CTA) characteristics of central CRT, then raise the diagnosis of this disorder. MATERIAL AND METHODS: A total of 301 eligible patients with ESRD who experienced both chest multi-phase multidetector CTA (MDCTA) and digital subtraction angiography were enrolled in the final analysis. The location, shape, and related signs of the central CRT in MDCTA images were evaluated. Independent-samples T test, chi-square test, and binary logistic regression were analyzed using SPSS software. RESULTS: In total, 166 patients were found to have CRT using MDCTA, and this was verified by DSA. Central CRT was usually irregular in the superior vena cava segment, and the angle of the contact area between central CRT and catheter was <180° (all P < 0.05). Age, collateral circulation, and venous stenosis were shown to have significant differences when compared to patients without CRT (all P < 0.05), but there were no significant differences about the sex or catheter insertion site. In addition, age and collateral circulation were the factors found to be significantly associated with thrombosis (P < 0.05). In particular, the thrombosis was 2.213 times more likely to be found in those patients with collateral circulation (odds ratio = 2.213, 95% confidence interval = 1.236-3.961). CONCLUSION: Chest multi-phase MDCTA can effectively reduce the missed diagnosis and misdiagnosis of central CRT. It is worth paying more attention to the central CRT especially when the collateral circulation is observed.


Assuntos
Cateteres Venosos Centrais , Falência Renal Crônica , Trombose , Trombose Venosa , Humanos , Angiografia por Tomografia Computadorizada , Veia Cava Superior , Trombose/etiologia , Trombose Venosa/diagnóstico por imagem , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Diálise Renal/efeitos adversos , Angiografia Digital , Tomografia Computadorizada Multidetectores , Catéteres/efeitos adversos , Cateteres Venosos Centrais/efeitos adversos
2.
Acta Radiol ; 59(1): 58-64, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28440669

RESUMO

Background Acute aortic dissection (AD) is a life-threatening medical emergency. It has been debated whether the multiphase dynamic computed tomography angiography (CTA) protocol is superior to the standard triphasic protocol for revealing the characteristics of AD. Purpose To examine two multiphase dynamic protocols, Dynamic four-dimensional (4D) CTA using the shuttle mode and Flash 4D CTA using the high-pitch mode for the assessment of AD and to compare them with the standard triphasic protocol. Material and Methods A total of 54 consecutive patients were randomly and equally assigned to three groups and scanned with a second-generation DSCT scanner. Groups A, B, and C were assessed with the Dynamic 4D CTA in the shuttle mode, the Flash 4D CTA in the high-pitch mode, and the standard triphasic acquisition protocol, respectively. Image quality of all patients was evaluated. The effective radiation dose (ED) was recorded. Results In 54 patients, CTA images could display the true and false lumens, the intimal flap, the entry tear, and branch vessel involvement in the AD. Compared with group C, additional diagnostic information was obtained in groups A and B, including the dynamic enhancement delay between the true and false lumens (A = 18, B = 18); the presence of membrane oscillation (A = 8, B = 14); dynamic ejection of the contrast material from the true lumen into the false lumen (A = 6, B = 7); and the dynamic obstruction of the left renal artery (B = 2). The ED in these three groups was significantly different ( P < 0.05). Conclusion Compared to the standard triphasic protocol, the multiphase dynamic CTA protocol is feasible and is able to reveal additional diagnostic information. Therefore, we recommend using the high-pitch, dual-source multiphase dynamic CTA to assess ADs.


Assuntos
Aneurisma Aórtico/diagnóstico por imagem , Dissecção Aórtica/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Tomografia Computadorizada Quadridimensional/métodos , Processamento de Imagem Assistida por Computador/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 31(5): 1117-20, 2014 Oct.
Artigo em Zh | MEDLINE | ID: mdl-25764733

RESUMO

This study aims to explore the clinical value of the computer-aided diagnosis (CAD) system for early detection of the pulmonary nodules on digital chest X-ray. A total of 100 cases of digital chest radiographs with pulmonary nodules of 5-20 mm diameter were selected from Pictures Archiving and Communication System (PACS) database in West China Hospital of Sichuan University were enrolled into trial group, and other 200 chest radiographs without pulmonary nodules as control group. All cases were confirmed by CT examination. Firstly, these cases were diagnosed by 5 different-seniority doctors without CAD, and after three months, these cases were re-diagnosed by the 5 doctors with CAD. Subsequently, the diagnostic results were analyzed by using SPSS statistical methods. The results showed that the sensitivity and specificity for detecting pulmonary nodules tended to be improved by using the CAD system, especially for specificity, but there was no significant difference before and after using CAD system.


Assuntos
Diagnóstico por Computador , Diagnóstico Precoce , Pulmão/patologia , Radiografia Torácica , China , Humanos , Intensificação de Imagem Radiográfica , Tórax
4.
Int J Biol Macromol ; 269(Pt 1): 132055, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704073

RESUMO

Pretreatment is the key step to convert lignocelluloses to sustainable biofuels, biochemicals or biomaterials. In this study, a green pretreatment method based on choline chloride-lactic acid deep eutectic solvent (ChCl-LA) and niobium-based single-atom catalyst (Nb/CN) was developed for the fractionation of corn straw and further enzymatic hydrolysis of cellulose. With this strategy, significant lignin removal of 96.5 % could be achieved when corn straw was pretreated by ChCl-LA (1:2) DES over Nb/CN under 120 °C for 6 h. Enzymatic hydrolysis of the cellulose-enriched fraction (CEF) presented high glucose yield of 92.7 % and xylose yield of 67.5 %. In-depth investigations verified that the high yields of fractions and monosaccharides was attributed to the preliminary fractionation by DES and the deep fractionation by Nb/CN. Significantly, compared to other reported soluble catalysts, the synthesized single-atom catalyst displayed excellent reusability by simple filtration and enzymatic hydrolysis. The recyclability experiments showed that the combination of ChCl-LA DES and Nb/CN could be repeated at least three times for corn straw fractionation, moreover, the combination displayed remarkable feedstock adaptability.


Assuntos
Colina , Solventes Eutéticos Profundos , Ácido Láctico , Lignina , Nióbio , Lignina/química , Nióbio/química , Catálise , Colina/química , Hidrólise , Solventes Eutéticos Profundos/química , Ácido Láctico/química , Zea mays/química , Fracionamento Químico/métodos
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 44(4): 578-83, 2013 Jul.
Artigo em Zh | MEDLINE | ID: mdl-24059112

RESUMO

OBJECTIVE: To evaluate the correlation between image quality and thoracic diameters, anteroposterior diameter (AP) and right-left diameter (RL) for the optimization of reducing radiation dose in coronary artery imaging with Dual-source CT. METHODS: 118 patients underwent CT coronary artery imaging (CTCA) were divided into two groups (A and B) according to body mass index (BMI). There were 58 patients in group A with BMI values > or = 25 kg/m2 and < 30 kg/m2; and 60 patients in group B with BMI values < 25 kg/m2. Scan parameters: collimation 64 X 0.6 mm, reconstruction slice thickness 0.75 mm, reconstructin interval 0.7 mm, FOV 150-180 mm, the pitch adjusted according to heart rate automatically. CT imagings were obtained with tube voltage 100 kV, tube current 330 mAs (group A) and 100 kV, tube current 220 mAs (group B). The contrast-noise ratio (CNR), signal to noise ratio (SNR), as well as blind correlation test score values were calculated to establish the relationship among BMI, AP, RL and CNR, SNR. RESULTS: RL of five levels in groups of A, B were correlated to CNRa (P < 0.05). In group A and B (except iii, iv level of Group A), AP were associated with CNRa (P < 0.05). In addition to ii, iv level of group A, v level of group B, BMI were associated with CNRa (P < 0.05). The correlation coefficient of CNRa and RL of group A except ii level was greater than that of CNRa and AP. The correlation coefficient of CNRa, SNRa and RL of group B was greater than that of CNRa, SNRa and AP. Except iii level, the correlation coefficient of CNRa, SNRa and AP of group A was greater than that of CNRa, SNRa and BMI. Except ii level, the correlation coefficient of CNRa and AP of group B was greater than that of CNRa and BMI. CONCLUSION: Thoracic diameter of RL can be used as a guider to select the appropriate scan protocol in the coronary imaging acqusition with dual-source CT.


Assuntos
Angiografia Coronária , Doses de Radiação , Intensificação de Imagem Radiográfica , Tórax/anatomia & histologia , Tomografia Computadorizada Espiral , Adulto , Idoso , Idoso de 80 Anos ou mais , Carga Corporal (Radioterapia) , Índice de Massa Corporal , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Comput Methods Programs Biomed ; 229: 107290, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36502546

RESUMO

BACKGROUND AND OBJECTIVES: There is a noticeable gap in diagnostic evidence strength between the thick and thin scans of Low-Dose CT (LDCT) for pulmonary nodule detection. When the thin scans are needed is unknown, especially when aided with an artificial intelligence nodule detection system. METHODS: A case study is conducted with a set of 1,000 pulmonary nodule screening LDCT scans with both thick (5.0mm), and thin (1.0mm) section scans available. Pulmonary nodule detection is performed by human and artificial intelligence models for nodule detection developed using 3D convolutional neural networks (CNNs). The intra-sample consistency is evaluated with thick and thin scans, for both clinical doctor and NN (neural network) models. Free receiver operating characteristic (FROC) is used to measure the accuracy of humans and NNs. RESULTS: Trained NNs outperform humans with small nodules < 6.0mm, which is a good complement to human ability. For nodules > 6.0mm, human and NNs perform similarly while human takes a fractional advantage. By allowing a few more FPs, a significant sensitivity improvement can be achieved with NNs. CONCLUSIONS: There is a performance gap between the thick and thin scans for pulmonary nodule detection regarding both false negatives and false positives. NNs can help reduce false negatives when the nodules are small and trade off the false negatives for sensitivity. A combination of human and trained NNs is a promising way to achieve a fast and accurate diagnosis.


Assuntos
Neoplasias Pulmonares , Nódulo Pulmonar Solitário , Humanos , Inteligência Artificial , Neoplasias Pulmonares/diagnóstico por imagem , Nódulo Pulmonar Solitário/diagnóstico por imagem , Redes Neurais de Computação , Tomografia Computadorizada por Raios X , Interpretação de Imagem Radiográfica Assistida por Computador
7.
Dalton Trans ; 51(4): 1502-1512, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34989367

RESUMO

Promising applications of lithium-sulfur batteries with high theoretical capacity are still severely limited due to the poor conductivity of sulfur, the polysulfide shuttle effect and volume expansion. Herein, low-cost and carbon/nitrogen-rich waste honeycombs are used to prepare in situ N-doped hierarchical porous carbon (INHPC) and firstly applied as a sulfur host by facile high-temperature carbonization combined with KHCO3 activation. The influence of mass ratios of the activator to honeycomb on the morphology and pore structure of the as-prepared carbon materials was investigated in detail. Among them, the optimized INHPC with a mass ratio of 4 : 1 presents block-like morphology with interconnected pore structure, while showing a high specific surface area of 1683.6 m2 g-1 and a large pore volume of 0.974 cm3 g-1. Moreover, the in situ N-doped carbon materials not only have good electronic conductivity but also strong chemical adsorption with polysulfide intermediates, hence effectively alleviating the shuttle effect. When used as the sulfur host, the as-obtained INHPC-4/S composite cathode with a sulfur content of 60 wt% delivers a high initial discharge capacity of 913.4 mA h g-1 and retains a reversible capacity of 538.3 mA h g-1 after 200 cycles at 0.2 C. Even at a current rate of 1 C, the first discharge capacity of 623.2 mA h g-1 can be obtained, simultaneously achieving the durable cycle life up to 500 cycles. These good electrochemical performances are ascribed to physicochemical synergistic adsorption of in situ N-doping and hierarchical porous structure as well as high ionic/electronic conductivity.

8.
Acta Pharmacol Sin ; 32(1): 126-32, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21170080

RESUMO

AIM: To evaluate the effect of inhaled formoterol-budesonide on airway remodeling in adult patients with moderate asthma. METHODS: Thirty asthmatic patients and thirty control subjects were enrolled. Asthmatic subjects used inhaled Symbicort 4.5/160 µg twice daily for one year. The effect of formoterol-budesonide on airway remodeling was assessed with comparing high-resolution computer tomography (HRCT) images of asthmatic patients and controls, as well as expression levels of cytokines and growth factors, inflammatory cell count in induced sputum, and airway hyper-responsiveness. RESULTS: The differences in age and gender between the two groups were not significant. However, differences in FVC %pred, FEV(1) %pred, and PC(20) between the two groups were significant. After treatment with formoterol-budesonide, the asthma patients' symptoms were relieved, and their lung function was improved. The WT and WA% of HRCT images in patients with asthma was increased, whereas treatment with formoterol-budesonide caused these values to decrease. The expression of MMP-9, TIMP-1, and TGF-ß(1) in induced sputum samples increased in patients with asthma and decreased dramatically after treatment with formoterol-budesonide. The WT and WA% are correlated with the expression levels of cytokines and growth factors, inflammatory cell count in induced sputum, and airway hyper-responsiveness, while these same values are correlated negatively with FEV(1)/FVC and FEV(1)%. CONCLUSION: Formoterol-budesonide might interfere in chronic inflammation and airway remodeling in asthmatic patients. HRCT can be used to effectively evaluate airway remodeling in asthmatic patients.


Assuntos
Remodelação das Vias Aéreas/efeitos dos fármacos , Asma/tratamento farmacológico , Broncodilatadores/uso terapêutico , Budesonida/uso terapêutico , Etanolaminas/uso terapêutico , Administração por Inalação , Adulto , Asma/imunologia , Asma/patologia , Broncodilatadores/administração & dosagem , Broncodilatadores/farmacologia , Budesonida/administração & dosagem , Budesonida/farmacologia , Citocinas/imunologia , Etanolaminas/administração & dosagem , Etanolaminas/farmacologia , Feminino , Fumarato de Formoterol , Humanos , Masculino , Escarro/efeitos dos fármacos , Escarro/imunologia
9.
Dalton Trans ; 50(46): 17052-17061, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34779450

RESUMO

The rational design of the unique morphology of particles has been considered as the key to improving the structural stability of spinel LiMn2O4 cathode materials for Li-ion batteries. Herein, a facile solid-state combustion process, combined with a Cr and Al co-doping approach, is proposed to prepare various LiCr0.01AlxMn1.99-xO4 (x ≤ 0.10) cathode materials with a good crystallinity. Cr and Al co-doping facilitates the formation of a single crystal truncated octahedral morphology. This endows the as-prepared LiCr0.01AlxMn1.99-xO4 with abundant {111} planes for Mn dissolution reduction and a few {100} and {110} planes for Li+ ion fast diffusion channels. Moreover, the introduction of Cr and Al elements with a stable electronic configuration further boosts the structural stability of the spinel LiMn2O4 owing to the relatively robust Al-O and Cr-O bonds compared with the Mn-O bond. Owing to these advantages, the optimal LiCr0.01Al0.05Mn1.94O4 delivers a good electrochemical performance with a high first discharge capacity of 118.5 mA h g-1 and a capacity retention of 70.8% after 1000 cycles at 1 C. Even at relatively high current rates of 15 and 20 C, a durable and prolonged cycling performance of up to 3000 cycles can be achieved. In addition, a high-temperature capacity retention of 72.1% is also maintained after 200 cycles at 5 C under 55 °C. This work provides potential candidates for developing long-life Li-ion batteries with a simultaneously high capacity.

10.
J Colloid Interface Sci ; 585: 729-739, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33121760

RESUMO

Various Li-rich spinel Li1+xNi0.05Mn1.95-xO4 (0 ≤ x ≤ 0.10) cathode materials with a truncated octahedron were synthesized by a solution combustion method. The relationship of crystalline structure, particles morphology and electrochemical properties of the as-prepared samples was investigated via a series of physicochemical characterizations. The Li-Ni co-doping changes the lattice parameters and atomic configuration, whilst resulting in a contraction of unit cell dimension and giving rise to a variation of bond length. In this regard, the shrinkage of octahedral MnO6 provides a robust structure and the expansion of tetrahedral LiO4 facilitates a fast electrochemical process. Additionally, the resulted polyhedral Li1+xNi0.05Mn1.95-xO4 samples present the exposed (110), (100), and (111) crystal planes, which provide the favorable Li+ ions diffusion/transmission channel and alleviate Mn dissolution. Owing to these merits of polyhedral structure and Li-Ni co-doping, the optimized Li1.02Ni0.05Mn1.93O4 exhibits good electrochemical performance with high initial discharge capacity of 119.8, 107.1 and 97.9 mAh·g-1 at 1, 5 and 10 C, respectively. Even at a high current rate of 15 C, an excellent capacity retention of 91.7% is obtained after 1000 cycles, whilst the high temperature performance was also improved.

11.
Radiology ; 254(1): 285-91, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20019132

RESUMO

PURPOSE: To determine the multidetector computed tomographic (CT) features of crush thoracic traumas resulting from the massive Sichuan earthquake. MATERIALS AND METHODS: This study was approved by the ethics committee of the medical school, and informed consent was waived. A retrospective review was undertaken of 215 multidetector chest CT scans of 112 male and 103 female patients who sustained crush thoracic injuries in the Sichuan earthquake at 2:28 pm Beijing time, May 12, 2008, and were rescued in the authors' hospital. Multidetector chest CT studies were performed between May 12, 2008, and June 7, 2008. The authors looked for injuries to the thoracic cage, pulmonary parenchyma, and pleura. RESULTS: One hundred forty-three patients (66.5%; 95% confidence interval [CI]: 60.2%, 72.8%) had at least one rib fracture; the mean number of rib fractures per patient was 6 [corrected]. Forty-five of these patients (31.5% of 143 patients; 95% CI: 23.9%, 39.1%) had flail chest, with a total of 288 ribs fractured. There were 46 patients (21.4%; 95% CI: 15.9%, 26.9%) with at least one vertebral fracture. There were 77 vertebral fractures total; 36 of these fractures were in T1 through T10. Twelve patients (5.6%; 95% CI: 2.5%, 8.7%) had sternal fractures, and 48 patients (22.3%; 95% CI: 16.7%, 27.9%) had either scapular or clavicular fractures. There were 117 patients (54.4%; 95% CI: 47.7%, 61.1%) with pulmonary parenchymal injuries and 146 (67.9%; 95% CI: 61.7%, 74.1%) with pleural injuries. CONCLUSION: Crush thoracic trauma resulting from the massive Sichuan earthquake was a life-threatening injury; this type of injury has the potential for multiple fractures and pulmonary parenchymal injuries.


Assuntos
Síndrome de Esmagamento/diagnóstico por imagem , Terremotos , Traumatismos Torácicos/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , China/epidemiologia , Síndrome de Esmagamento/epidemiologia , Feminino , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Traumatismos Torácicos/epidemiologia , Tomografia Computadorizada por Raios X
12.
AJR Am J Roentgenol ; 195(1): W76-80, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20566785

RESUMO

OBJECTIVE: The purpose of this study was to investigate the effect of the degree of sternal depression on the cardiac rotation of pectus excavatum as depicted with helical CT. MATERIALS AND METHODS: Sixty-three patients (53 boys, 10 girls; mean age, 9.7 +/- 7 years) with pectus excavatum who underwent helical chest CT and surgical correction were included in this study. Depth of sternal depression, CT depression index, cardiac rotation angle, and pulmonary vein angle were measured, and the correlation of these parameters was analyzed. RESULTS: The mean sternal depression was 21 +/- 7 mm; CT depression index, 2.7 +/- 1.4; cardiac rotation angle, 55 degrees +/- 9 degrees ; and pulmonary vein angle, 52 degrees +/- 12 degrees . The sternal depression (18 mm) in patients with a CT depression index less than 2.4 was less than that in patients with a CT depression index of 2.4-2.9 (sternal depression, 21 mm) or greater than 2.9 (sternal depression, 28 mm) (p < 0.01). Similarly, the cardiac rotation angle (49 degrees +/- 5 degrees ) in patients with a CT depression index less than 2.4 was smaller than that in patients with a CT depression index of 2.4-2.9 (55 degrees +/- 6 degrees ) or greater than 2.9 (64 degrees +/- 12 degrees ) (p < 0.01). The pulmonary vein angle in patients with a CT depression index less than 2.4 (59 degrees +/- 11 degrees ) was larger than that in patients with a CT depression index of 2.4-2.9 (50 degrees +/- 12 degrees ) or a CT depression index greater than 2.9 (45 degrees +/- 8 degrees ) (p < 0.01). Cardiac rotation angle had a positive correlation with CT depression index (r = 0.75, p < 0.01). CONCLUSION: The degree of sternal depression has a positive correlation with the degree of cardiac rotation in pectus excavatum. Helical CT is a valuable technique for evaluating the chest deformity and resultant cardiac rotation.


Assuntos
Tórax em Funil/diagnóstico por imagem , Coração/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adolescente , Criança , Feminino , Tórax em Funil/cirurgia , Humanos , Masculino , Interpretação de Imagem Radiográfica Assistida por Computador
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(8): 2289-91, 2010 Aug.
Artigo em Zh | MEDLINE | ID: mdl-20939359

RESUMO

The seven metal elements in Yunnan wild schizophyllum commune Fr, including Zn, Co, Ni, Cu, Fe, Cr and Mg, were determined by atomic absorption spectrometry for providing a scientific basis of the development. The results show that Zn, Co, Ni, Fe, Cr and Mg are relatively rich in schizophyllum commune Fr and the content of Cu is lower. The ratio of the content of Zn to that of Cu is 7.4, which is consistent with the relative content level of Zn and Cu contained in many anticancer Chinese traditional plants, implying that the nutritive value of Yunnan wild schizophyllum commune Fr is high.


Assuntos
Metais/análise , Schizophyllum/química , Espectrofotometria Atômica
14.
Med Image Anal ; 65: 101772, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32674041

RESUMO

The accurate identification of malignant lung nodules using computed tomography (CT) screening images is vital for the early detection of lung cancer. It also offers patients the best chance of cure, because non-invasive CT imaging has the ability to capture intra-tumoral heterogeneity. Deep learning methods have obtained promising results for the malignancy identification problem; however, two substantial challenges still remain. First, small datasets cannot insufficiently train the model and tend to overfit it. Second, category imbalance in the data is a problem. In this paper, we propose a method called MSCS-DeepLN that evaluates lung nodule malignancy and simultaneously solves these two problems. Three light models are trained and combined to evaluate the malignancy of a lung nodule. Three-dimensional convolutional neural networks (CNNs) are employed as the backbone of each light model to extract the lung nodule features from CT images and preserve lung nodule spatial heterogeneity. Multi-scale input cropped from CT images enables the sub-networks to learn the multi-level contextual features and preserve diverse. To tackle the imbalance problem, our proposed method employs an AUC approximation as the penalty term. During training, the error in this penalty term is generated from each major and minor class pair, so that negatives and positives can contribute equally to updating this model. Based on these methods, we obtain state-of-the-art results on the LIDC-IDRI dataset. Furthermore, we constructed a new dataset collected from a grade-A tertiary hospital and annotated using biopsy-based cytological analysis to verify the performance of our method in clinical practice.


Assuntos
Neoplasias Pulmonares , Nódulo Pulmonar Solitário , Humanos , Pulmão , Neoplasias Pulmonares/diagnóstico por imagem , Redes Neurais de Computação , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X
15.
Zhongguo Fei Ai Za Zhi ; 23(5): 299-305, 2020 May 20.
Artigo em Zh | MEDLINE | ID: mdl-32279474

RESUMO

BACKGROUND: Mortality of lung cancer can be decreased by early screening effectively. However, consistent and proficient standards & methods have not been established in China. This study was based on pulmonary nodules/lung cancer comprehensive management platform established by West China Hospital, Sichuan University. Early screening of pulmonary nodules was integrated into standard healthcare of lung cancer system, aiming to improve survivals of lung cancer patients. METHODS: Three cohorts were established: healthy populations, pulmonary nodules cohort and lung cancer patients cohort, and related clinical data will be collected and analyzed. Preliminary plan includes verifying effect of pulmonary nodules screening module. RESULTS: Pulmonary nodules screening was performed in 2,836 employers (>40 years old) of West China Hospital. Lung cancers were diagnosed in 66 participants, all receiving surgery to remove the lesions. 65 of them were with early stage diseases, 1 with lung cancer and brain metastasis. CONCLUSIONS: Proficient screening, follow-up and healthcare can be achieved via pulmonary nodules/lung cancer comprehensive management mode, which will be extended all over west China region in future.


Assuntos
Neoplasias Pulmonares/diagnóstico , Nódulos Pulmonares Múltiplos/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Detecção Precoce de Câncer , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Tomografia Computadorizada por Raios X
16.
J Colloid Interface Sci ; 555: 64-71, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31376769

RESUMO

The improvements of cyclability and rate capability of lithium ion batteries with spinel LiMn2O4 as cathode are imperative demands for the large-scale practical applications. Herein, a nickel (Ni) and magnesium (Mg) co-doping strategy was employed to synthesize LiNi0.03Mg0.05Mn1.92O4 cathode material via a facile solid-state combustion approach. The effects of the Ni-Mg co-doping on crystalline structure, micromorphology and electrochemical behaviors of the as-prepared LiNi0.03Mg0.05Mn1.92O4 are investigated by a series of physico-chemical characterizations and performance tests at high-rate and elevated-temperature. The resultant LiNi0.03Mg0.05Mn1.92O4 has the intrinsic spinel structure with no any impurities, and exhibits an elevated average valence of manganese in comparison to the pristine LiMn2O4. Owing to the Ni and Mg dual-doped merits, the LiNi0.03Mg0.05Mn1.92O4 sample demonstrates a robust spinel structure and high first discharge specific capacity of 112.3 mAh g-1, whilst undergoing a long cycling of 1000 cycles at 1 C. At a high current rate of 20 C, the capacity of 91.2 mAh g-1 with an excellent retention of 77% is obtained after 1000 cycles. Even at 10 C under 55 °C, an excellent capacity of 97.6 mAh g-1 is also delivered. These results offer a new opportunity for developing high-performance lithium ion batteries with respect to the Ni-Mg co-doping strategy.

17.
Sci Rep ; 9(1): 16864, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31728020

RESUMO

Various nickel and magnesium dual-doped LiNixMg0.08Mn1.92-xO4 (x ≤ 0.15) were synthesized via a modified solid-state combustion method. All as-prepared samples show typical spinel phase with a well-defined polyhedron morphology. The Ni-Mg dual-doping obviously decreases the lattice parameter that gives rise to the lattice contraction. Owing to the synergistic merits of metal ions co-doping, the optimized LiNi0.03Mg0.08Mn1.89O4 delivers high initial capacity of 115.9 and 92.9 mAh·g-1, whilst retains 77.1 and 69.7 mAh·g-1 after 1000 cycles at 1 C and high current rate of 20 C, respectively. Even at 10 C and 55 °C, the LiNi0.03Mg0.08Mn1.89O4 also has a discharge capacity of 92.2 mAh·g-1 and endures 500 cycles long-term life. Such excellent results are contributed to the fast Li+ diffusion and robust structure stability. The anatomical analysis of the 1000 long-cycled LiNi0.03Mg0.08Mn1.89O4 electrode further demonstrates the stable spinel structure via the mitigation of Jahn-Teller effect. Hence, the Ni-Mg co-doping can be a potential strategy to improve the high-rate capability and long cycle properties of cathode materials.

18.
Adv Ther ; 25(4): 342-54, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18421428

RESUMO

INTRODUCTION: Angiogenesis and microvascular remodelling may play a vital role in the chronic inflammatory process within asthma. One of the most important factors involved in angiogenesis is vascular endothelial growth factor (VEGF). In this study we hypothesised that an increased expression of VEGF may be involved in airway remodelling in asthma patients. To this end, we compared the histology and expression levels of VEGF and one of its receptors (VEGFR1) in bronchial tissues of patients with asthma compared with control patients. We also investigated the effect of treatment with budesonide/formoterol (Symbicort; AstraZeneca, Lund, Sweden) in the relationship between VEGF and airway remodelling. METHODS: Bronchial tissues were obtained from patients attending the West China Hospital from April to November 2006. Thirteen patients were diagnosed with moderate asthma and 10 others were treated as control. Histological and immunohistochemical comparisons between asthmatic and control patients were made at baseline, and (for asthmatic subjects) following 6 months of treatment with budesonide/formoterol. RESULTS: Compared with control patients, asthmatic patients had significantly decreased respiratory parameters, including forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV(1)) (% predictive). Furthermore, patients with asthma had submucosal gland hyperplasia, increased smooth muscle mass, increased subepithelial fibrosis and neovascularisation. Asthmatic patients also exhibited increased expression of VEGF and VEGFR1 within epithelial cells. The increased expression of VEGF and its receptor correlated well with airway remodelling, airflow obstruction and airway hyper-responsiveness. After treatment with budesonide/formoterol for 6 months, the expression of VEGF and VEGFR1 was decreased, with correlatory decreased airway remodelling in patients with asthma. CONCLUSION: The increased expression of VEGF and VEGFR(1) in asthmatic patients is accompanied by an increased number and size of blood vessels in asthmatic airways, as well as airway remodelling. Budesonide/formoterol therapy for 6 months can decrease the expression of VEGF and VEGFR(1) alongside airway remodelling in asthma. The inhibition of VEGF and its receptor may be a good therapeutic strategy for asthma.


Assuntos
Corticosteroides/uso terapêutico , Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Budesonida/uso terapêutico , Etanolaminas/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/biossíntese , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Corticosteroides/farmacologia , Adulto , Antiasmáticos/farmacologia , Asma/metabolismo , Asma/patologia , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Brônquios/patologia , Budesonida/farmacologia , Combinação Budesonida e Fumarato de Formoterol , Combinação de Medicamentos , Etanolaminas/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica , Testes de Função Respiratória
19.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 39(5): 788-91, 2008 Sep.
Artigo em Zh | MEDLINE | ID: mdl-19024315

RESUMO

OBJECTIVE: To investigate the clinical application of first-pass perfusion MDCT in the assessment of tumor angiogenesis in carcinoma of esophagus and cardia. METHODS: CT perfusion was performed with multi-detector row CT (MDCT) in 44 patients with carcinoma of esophagus and esophagogastric junction, who was diagnosed with pathological results and did not received any anti-tumor therapy. Twenty-one patients with peripheral lung cancer but normal esophagus were served as controls. Perfusion parameters were compared between normal and malignant esophagus, between adenocarcinoma and squamous cell carcinoma, as well as between tumors with metastases and those without metastases. RESULTS: Carcinoma of esophagus and esophagogastric junction showed higher blood flow, peak enhancement index, blood volume, and shorter time to peak compared with normal esophagus (P < 0.05). There were no statistically significant differences in perfusion parameters between adenocarcinoma and squamous cell carcinoma (P > 0.05), whereas tumors with metastases showed higher blood flow and shorter time to peak compared with those without metastases (P < 0.05). CONCLUSION: MDCT perfusion could assess tumor vascularity in carcinoma of esophagus and esophagogastric junction, and tumor vascularity or angiogenesis was not influenced by its histological type. However, high blood flow and short time-to-peak may be helpful to predict tumor metastases.


Assuntos
Neoplasias Esofágicas/diagnóstico por imagem , Neovascularização Patológica/diagnóstico por imagem , Neoplasias Gástricas/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Cárdia , Neoplasias Esofágicas/irrigação sanguínea , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Perfusão/métodos , Estudos Prospectivos , Fluxo Sanguíneo Regional , Neoplasias Gástricas/irrigação sanguínea , Neoplasias Gástricas/patologia
20.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 39(3): 492-5, 2008 May.
Artigo em Zh | MEDLINE | ID: mdl-18575351

RESUMO

OBJECTIVE: To study the clinical value of coronary artery calcification score with 64-slice MDCT in the diagnosis of coronary artery disease (CAD). METHODS: 96 subjects including 49 with confirmed CAD (CAD group) and 47 asymptomatic people as control group were recruited between May 2006 and December 2006 by the department of radiology in our hospital. The selective coronary angiography was also performed in 30 subjects including 25 with CAD and 5 asymptomatic people and subsequently divided into three groups (< 50%, 50%-75% and > 75% of maximum degree of vessel occlusion). We investigated the correlation of calcification score (CS) and the maximum degree of vessel occlusion measured by coronary angiography were investigated. RESULTS: The larger CS and more numbers of regions of interest of calcification in the right coronary artery and left anterior descending artery in 96 subjects were observed. The total mean CS of CAD (462 +/- 314) was higher than that of control group (83 +/- 52) (P < 0.001). There was a moderate correlation between degree of vessel stenosis and CS for individual vessels in patients with positive calcium scan(r = 0. 445, P < 0.01). CONCLUSION: Although CS measured by MDCT is not an accurate marker of the degree of vessel stenosis in CAD, it can be applied as a screening tool for high risk CAD patients and could greatly reduce the expense on coronary angiography.


Assuntos
Calcinose/diagnóstico por imagem , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/patologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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