Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
1.
J Sci Food Agric ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39149861

RESUMEN

BACKGROUND: Leaf area index (LAI) is an important indicator for assessing plant growth and development, and is also closely related to photosynthesis in plants. The realization of rapid accurate estimation of crop LAI plays an important role in guiding farmland production. In study, the UAV-RGB technology was used to estimate LAI based on 65 winter wheat varieties at different fertility periods, the wheat varieties including farm varieties, main cultivars, new lines, core germplasm and foreign varieties. Color indices (CIs) and texture features were extracted from RGB images to determine their quantitative link to LAI. RESULTS: The results revealed that among the extracted image features, LAI exhibited a significant positive correlation with CIs (r = 0.801), whereas there was a significant negative correlation with texture features (r = -0.783). Furthermore, the visible atmospheric resistance index, the green-red vegetation index, the modified green-red vegetation index in the CIs, and the mean in the texture features demonstrated a strong correlation with the LAI with r > 0.8. With reference to the model input variables, the backpropagation neural network (BPNN) model of LAI based on the CIs and texture features (R2 = 0.730, RMSE = 0.691, RPD = 1.927) outperformed other models constructed by individual variables. CONCLUSION: This study offers a theoretical basis and technical reference for precise monitor on winter wheat LAI based on consumer-level UAVs. The BPNN model, incorporating CIs and texture features, proved to be superior in estimating LAI, and offered a reliable method for monitoring the growth of winter wheat. © 2024 Society of Chemical Industry.

2.
Ann Transl Med ; 10(1): 27, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35242872

RESUMEN

We report a case of a well-defined lesion in an asymptomatic patient with lipomatous ganglioneuroma (LG) located close to the left thoracic spine. Its intensity was heterogeneous with adipocytes. The lesion extended into the spinal canal through the enlarged left intervertebral without bony erosion. The imaging, clinical, and pathological features of the tumor are analyzed. Contrast-enhanced magnetic resonance imaging (MRI) revealed that the lesion was moderate enhanced. 18-F-fluoro-2-deoxyglucose-positron emission tomography/computed tomography (18FDG-PET/CT) demonstrated high 18-F-fluoro-2-deoxyglucose (18FDG) uptake of the tumor lesion. The finial preoperative diagnosis from our radiologists was that the tumor may be a liposarcoma or neurogenic tumor, but pathology showed that this was incorrect. Some related literatures were reviewed for reference to summarize imaging characteristics of this disease and to assist radiologists in making more accurate diagnoses. All of the lesions had adipocytes in reviewed literature, and the fat-suppressed images showed that there was some low signal intensity within the lesions, some lesions had widened neural foramina and extended into the spinal canal, and some lesion had calcifications. LG is an extremely rare variant of ganglioneuroma. Using the correct measurement of the CT value, applying MRI for fat-suppressed images, using in phase, out phase and contrast-enhanced sequences, using FDG-PET/CT, mastering LG imaging diagnostics characteristics, and combining all of this with clinical, morphological characteristics and pathology results can help clinical workers decrease the misdiagnosis rate of LG.

3.
Arch Osteoporos ; 16(1): 3, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33394305

RESUMEN

To establish a model for osteoporosis risk in patients with rheumatoid arthritis and validate the model. A newly generated predictive model has been suggested to have good differentiation, calibration, and clinical validity and may be a useful clinical model for predicting osteoporosis in patients with rheumatoid arthritis. PURPOSE: To establish a prediction model for osteoporosis risk in patients with rheumatoid arthritis and validate the model internally and externally. METHODS: A total of 270 patients with rheumatoid arthritis who underwent bone mineral density measurement at our hospital from June 2019 to June 2020 were enrolled in the study. The patients were divided into two groups according to their entry time: a training set containing the first 2/3 of the patients (n = 180) and a validation set containing the remaining 1/3 of the patients (n = 90). Binary logistic regression analysis was used to establish the regression models, and the concordance index (C-index), calibration plot, and decision curve analysis were used to evaluate the prediction model. RESULTS: Five variables, including age (X1), course of disease (X2), the disease activity score using 28 joint counts (DAS28) (X4), anti-cyclic citrullinated peptide antibody (CCP) (X7), and 7-joint ultrasonic bone erosion (X14), were selected to enter the model. The prediction model is Logit Y = - 12.647 + 0.133X1 + 0.011X2 + 0.754X4 + 0.001X7 + 0.605X14. The model had good differentiation; the C-index in the internal verification was 0.947 (95% CI is 0.932-0.977) and the C-index in the external verification was 0.946 (95% CI is 0.940-0.994). The calibration plot of the model showed excellent consistency between the prediction probability and actual probability. When > 0.483 was taken as the cutoff value for the diagnosis of osteoporosis, the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and Jordan index of the model were 90.24%, 87.76%, 7.37, 0.11, and 78.00%, respectively. CONCLUSION: A newly generated predictive model has been suggested to have good differentiation, calibration, and clinical validity and may be a useful clinical model for predicting osteoporosis in patients with rheumatoid arthritis.


Asunto(s)
Artritis Reumatoide , Osteoporosis , Autoanticuerpos , Densidad Ósea , Humanos , Osteoporosis/diagnóstico , Osteoporosis/epidemiología
4.
Eur Radiol ; 31(1): 45-54, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32780208

RESUMEN

OBJECTIVES: To determine the sonographic characteristics of borderline tumors (BoTs) and cystadenofibromas (CAFs). METHODS: Preoperative sonograms from consecutive patients who had at least one primary epithelial tumor in the adnexa were retrospectively collected. All tumors were described using the International Ovarian Tumor Analysis terminology. Ultrasound variables were tested using multinomial logistic regression after univariate analysis. RESULTS: A total of 650 patients were included in this study. Of these, 110 had a CAF, 128 had a BoT, 249 had a cystadenoma (CAD), and 163 had a cystadenocarcinoma (CAC). Nearly half of CAFs and more than half of BoTs and CACs appeared to be unilocular and multilocular solid on the ultrasound images, while CADs were predominantly uni- or multilocular (p < 0.001). Overall, shadowing was identified in 82/650 cases. Sixty-five of 110 (59.1%) CAFs exhibited an acoustic shadow, compared with only 4/249 (1.6%) in CADs, 7/128 (5.5%) in BoTs, and 6/163 (3.7%) in CACs (p < 0.001). Furthermore, 112/650 cases demonstrated microcystic pattern (MCP). Sixty-eight of 128 (53.1%) BoTs exhibited MCP, compared with only 5/249 (2.0%) in CADs, 19/163 (11.7%) in CACs, and 20/110 (18.2%) in CAFs (p < 0.001). Logistic regression analysis revealed that shadowing is an independent predictor of CAFs, while MCP is an independent predictor of BoTs. CONCLUSIONS: Sonographic findings for CAFs and BoTs were complex and partly overlapped with those for CACs. However, proper recognition and utilization of shadowing or MCP may help to correctly discriminate CAFs and BoTs. KEY POINTS: • Sonographic findings for borderline tumors and cystadenofibromas are complex and mimic malignancy. • Microcystic pattern and shadowing are independent predictors of borderline tumors and cystadenofibromas respectively.


Asunto(s)
Cistoadenofibroma , Neoplasias Ováricas , Cistoadenofibroma/diagnóstico por imagen , Femenino , Humanos , Neoplasias Ováricas/diagnóstico por imagen , Estudios Retrospectivos , Ultrasonografía
5.
Small ; 15(34): e1902220, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31267644

RESUMEN

Li-CO2 batteries can not only capture CO2 to solve the greenhouse effect but also serve as next-generation energy storage devices on the merits of economical, environmentally-friendly, and sustainable aspects. However, these batteries are suffering from two main drawbacks: high overpotential and poor cyclability, severely postponing the acceleration of their applications. Herein, a new Co-doped alpha-MnO2 nanowire catalyst is prepared for rechargeable Li-CO2 batteries, which exhibits a high capacity (8160 mA h g-1 at a current density of 100 mA g-1 ), a low overpotential (≈0.73 V), and an ultrahigh cyclability (over 500 cycles at a current density of 100 mA g-1 ), exceeding those of Li-CO2 batteries reported so far. The reaction mechanisms are interpreted depending on in situ experimental observations in combination with density functional theory calculations. The outstanding electrochemical properties are mostly associated with a high conductivity, a large fraction of hierarchical channels, and a unique Co interstitial doping, which might be of benefit for the diffusion of CO2 , the reversibility of Li2 CO3 products, and the prohibition of side reactions between electrolyte and electrode. These results shed light on both CO2 fixation and new Li-CO2 batteries for energy storage.

6.
Curr Med Res Opin ; 31(6): 1047-55, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25892216

RESUMEN

OBJECTIVE: Several lines of evidence suggest that estrogen receptor alpha (ER-α) gene polymorphism may influence the development of osteoarthritis (OA). However, the results are inconsistent. The aim of this study was to explore using a meta-analysis whether rs2234693 (ER-α PvuII T/C) polymorphism confers significant susceptibility to OA. METHODS AND RESULTS: A systematic search of all relevant studies published through 17 August 2014 was conducted using the PubMed, Web of Science, Embase, Cochrane database, Current Controlled Trials, Clinicaltrials.gov, Chinese Clinical Trial Registry, CBMdisc, CNKI and Google Scholar. All statistical analyses were done with Review Manager 5.1.4. Twelve articles involving 15 studies were included in the final meta-analysis, which contained 6417 OA cases and 8605 controls. Overall, no significant association was found between the rs2234693 polymorphism and OA risk when all studies were pooled into the meta-analysis (for C allele vs. T allele: OR = 0.99, 95% CI = 0.94-1.04, p = 0.63; for C/C vs. T/T: OR = 0.97, 95% CI = 0.87-1.08, p = 0.53; for C/C vs. T/C + T/T: OR = 0.96, 95% CI = 0.88-1.06, p = 0.43; for C/C + T/C vs. T/T: OR = 1.00, 95% CI = 0.89-1.14, p = 0.94). In the subgroup analysis, significant association was found between the rs2234693 polymorphism and the OA risk in the knee osteoarthritis (KOA) group (for C/C + T/C vs. T/T: OR = 1.15, 95% CI = 1.02-1.29, p = 0.02). CONCLUSIONS: The present meta-analysis suggests that the rs2234693 polymorphism is associated with an increased KOA risk. Additional well designed genome-wide association studies are required to confirm the result.


Asunto(s)
Receptor alfa de Estrógeno/genética , Predisposición Genética a la Enfermedad , Osteoartritis de la Rodilla/genética , Humanos , Osteoartritis/genética , Polimorfismo Genético
7.
Zhongguo Gu Shang ; 23(1): 17-9, 2010 Jan.
Artículo en Chino | MEDLINE | ID: mdl-20191957

RESUMEN

OBJECTIVE: To study the correlation between the MRI and some symptom scores of the patients with lumbar disc herniation (LDH), such as VAS (visual analogue scale), JOA (Japanese orthopedic association scale),and SLR (straight leg raising test) before and after manipulative therapy. METHODS: From June to December in 2007, 70 patients with LDH were selected in the study. Among the patients, 40 patients were male and 30 patients were female, ranging in age from 21 to 56 years (averaged 39 years). MRI was used to measure the size and position of the protruded nucleus pulposus (size of disc protrution, the angle between nerve root canal and disc protrution). Correlation study was conducted between the MRI and VAS, JOA, and SLR before and after therapy. The correlation between the changes of MRI and that of the quantified clinical indexes of LDH patients was also analyzed. RESULTS: There were significant differences before and after therapy in some quantified indexes for the clinical manifestation of the patients, such as VAS, JOA,and SLR. There were no significant changes in the shape and size of protrude nucleus pulposus after 20 days' therapy by CT or MR recheck. Correlation study between the quantified indexes of clinical manifestation (JOA) and MRI before and after the treatment showed that there was no significant correlation. CONCLUSION: The study proves again that the shape and size of protrude nucleus pulposus has no paralleled relation with the patient's clinical manifestation,which is demonstrated by the recheck of MRI after a successful spinal manipulative treatment in the study.


Asunto(s)
Desplazamiento del Disco Intervertebral/patología , Desplazamiento del Disco Intervertebral/terapia , Vértebras Lumbares/patología , Imagen por Resonancia Magnética , Manipulaciones Musculoesqueléticas , Adulto , Femenino , Humanos , Desplazamiento del Disco Intervertebral/diagnóstico , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA