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1.
Zhonghua Yi Xue Za Zhi ; 103(25): 1911-1917, 2023 Jul 04.
Artículo en Chino | MEDLINE | ID: mdl-37402672

RESUMEN

Objective: To investigate low-frequency fluctuation amplitude changes in resting-state brain fMRI and its correlation with clinical hearing levels in patients with clinical hearing level in patients with unilateral hearing impairment. Methods: Forty-five patients with unilateral hearing impairment[12 males and 33 females, aged 36-67 (46.0±9.7) years], and 31 controls with normal hearing[9 males and 22 females, aged 36-67 (46.0±10.1) years], were retrospectively included. All subjects underwent blood oxygen level-dependent (BOLD) resting-state functional magnetic resonance imaging and high-resolution T1-weighted imaging. The patients were divided into the left-sided hearing impaired group(24 cases), and the right-sided hearing impaired group(21 cases). After data being preprocessed, differences in low frequency amplitude (ALFF) metrics between the evaluated patients and controls were calculated and analyzed, and the statistics were corrected for Gaussian random field (GFR). Results: Overall comparative analysis of patients with hearing impairment showed that one-way ANOVA among the three groups showed abnormal ALFF values only in the right anterior cuneiform lobe (GRF adjusted P=0.002). The ALFF value of the hearing impaired group was higher than that of the control group in one cluster (peak coordinates: X=9, Y=-72, Z=48, T=5.82), involving the left occipital gyrus, right anterior cuneiform lobe, left superior cuneiform lobe, left superior parietal gyrus, and left angular gyrus (GRF adjusted P=0.031). The ALFF value of the hearing impaired group was lower than that of the control group in three clusters (peak coordinates: X=57, Y=-48, Z=-24; T=-4.99; X=45, Y=-66, Z=0, T=-4.06; X=42, Y=-12, Z=36, T=-4.03), involving the right inferior temporal gyrus, the right middle temporal gyrus, and the right precentral gyrus (GRF adjusted P=0.009). Compared with the control group, the ALFF value of the left hearing impairment group was significantly higher than that of the control group in one cluster (peak coordinates: X=-12, Y=-75, Z=45, T=5.78), involving the left anterior cuneiform lobe, right anterior cuneiform lobe, left middle occipital gyrus, left superior parietal gyrus, left superior occipital gyrus, left cuneiform lobe, and right cuneiform lobe (P=0.023 after GRF correction). Compared with the control group, the right hearing impairment group had a significantly higher ALFF value in one cluster (peak coordinates: X=9, Y=-46, Z=22, T=6.06), involving the left middle occipital gyrus, right anterior cuneiform lobe, left cuneiform lobe, right cuneiform lobe, left superior occipital gyrus, and right superior occipital gyrus (GRF adjusted P=0.022); The brain area with reduced ALFF values is located in the right inferior temporal gyrus (GRF adjusted P=0.029). Spearman's two-tailed correlation analysis between ALFF values and pure tone average in the abnormal brain regions showed that ALFF values in the abnormal brain regions correlated to some extent with the pure tone average (PTA) only in the left-sided hearing impaired group(PTA=2 000 Hz, r=0.318,P=0.033;PTA=4 000 Hz,r=0.386,P=0.009). Conclusion: The abnormal neural activity within the brain are different in patients with left-sided and right-sided hearing impairment, and the severity of hearing impairment is related to the difference in functional integration of brain regions.


Asunto(s)
Mapeo Encefálico , Pérdida Auditiva , Masculino , Femenino , Humanos , Estudios Retrospectivos , Encéfalo , Imagen por Resonancia Magnética/métodos , Audición
2.
Zhonghua Yi Xue Za Zhi ; 103(23): 1759-1766, 2023 Jun 20.
Artículo en Chino | MEDLINE | ID: mdl-37305935

RESUMEN

Objectives: To analyze the influence of vitamin D supplementation on clinical efficacy and drug retention rate of vedolizumab (VDZ) in patients with ulcerative colitis (UC). Methods: Retrospective study. By retrieving the clinical database of the Second Affiliated Hospital of Wenzhou Medical University, the patients with moderately to severely active UC were collected, who underwent VDZ treatment from January 2020 to June 2022. The modified Mayo score and Mayo endoscopic score (MES) were employed to evaluate disease activity and intestinal inflammation in UC patients, respectively. According to whether vitamin D was supplemented during VDZ treatment, the patients were divided into supplementary group and non-supplementary group. According to baseline serum 25(OH) D level, UC patients were divided into vitamin D deficiency group and non-deficiency group. According to whether vitamin D was supplemented, the patients of each group were divided into supplementary subgroup and non-supplementary subgroup, respectively. The clinical response rate, clinical remission rate and mucosal healing rate at week 30 after receiving VDZ treatment and the retention rate of VDZ at the 72nd week were observed. The effect of baseline serum 25 (OH) D level on the efficacy of vitamin D supplementation was analyzed by chi-square test. The effects of vitamin D supplementation on the clinical efficacy and drug retention of VDZ in UC were analyzed by chi-square test and Kaplan-Meier curve, respectively. Results: A total of 80 patients with moderately to severely active UC, who were aged (39.4±13.0) years(18-75 years), 37 male and 43 female, were included. There were 43 cases in supplementary group and 37 cases in non-supplementary group. There were 59 cases in the deficiency group, including 32 cases in the supplementary subgroup and 27 cases in the non-supplementary subgroup. There were 21 cases in the non-deficiency group, including 11 cases in the supplementary subgroup and 10 cases in the non-supplementary subgroup. At week 30, the average level of serum 25(OH) D was shown to be higher in supplementary group than that at week 0 [(24.5±5.4) vs (17.7±6.7) µg/L, P<0.001]. At week 30, in contrast with non-supplementary group, erythrocyte sedimentation rate(ESR)[75.0% (24.3%, 86.7%) vs 32.7% (-2.6%, 59.3%), P=0.005] and modified Mayo score [(4.7±2.8) vs (2.3±2.7) points, P<0.001] and MES score [(1.2±1.1) vs (0.4±0.9) points, P=0.001] were significantly reduced, clinical response rate [79.1%(34/43) vs 56.8%(21/37), P=0.032], clinical remission rate [67.4%(29/43) vs 29.7%(11/37), P=0.001] and mucosal healing rate [72.1%(31/43) vs 37.8%(14/37), P=0.002] were higher. At week 72, drug retention rate of VDZ was shown to be higher in supplementary group than in non-supplementary group [55.8%(24/43) vs 27.0%(10/37), P=0.004]. The further analysis showed that vitamin D supplementation could only improve clinical response rate[71.9%(23/32) vs 44.4%(12/27), P=0.033], clinical remission rate[62.5%(20/32) vs 14.8%(4/27), P<0.001], mucosal healing rate[68.8%(22/32) vs 22.2%(6/27), P<0.001] and drug retention rate [53.1%(17/32) vs 13.8%(4/27), P=0.001] in the patients with vitamin D deficiency. Conclusion: Vitamin D supplementation contributes to improving clinical response rate, clinical remission rate, mucosal healing rate and drug retention rate of VDZ in UC patients.


Asunto(s)
Colitis Ulcerosa , Humanos , Femenino , Masculino , Colitis Ulcerosa/tratamiento farmacológico , Estudios Retrospectivos , Resultado del Tratamiento , Vitaminas , Vitamina D/uso terapéutico , Suplementos Dietéticos
3.
Zhonghua Nei Ke Za Zhi ; 61(7): 785-792, 2022 Jul 01.
Artículo en Chino | MEDLINE | ID: mdl-35764562

RESUMEN

Objective: To analyze the influence of vitamin D3 supplementation on the clinical efficacy of mesalazine in patients with ulcerative colitis (UC). Methods: From January 2015 to December 2020, patients with mild-to-moderate active UC were retrospectively and continuously enrolled, who accepted mesalazine treatment for at least 12 months at the Second Affiliated Hospital of Wenzhou Medical University. According to simultaneous supplement of vitamin D3 (125 IU/d), the patients were divided into study group and control group. Demographic and disease characteristics, serum 25-hydroxyvitamin D[25(OH)D] levels and other information were collected through retrieving hospital database. Student's t-test, Mann-Whitney U test and Chi-square test were applied for comparison of disease characteristics. The changes of modified Mayo scores[ΔMayo] and 25(OH)D[Δ25(OH)D] were compared before and after treatment by paired t-test, Wilcoxon signed rank test and Chi-square test. Multiple linear regression model was used to analyze the independent factors affecting ΔMayo and Δ25(OH)D, and variables with P-values less than 0.20 in the univariate analysis were allowed for further multivariate analysis. Results: A total of 74 UC patients (44 males, 30 females), with median age (range) 39.5 (20-76) years old, were analyzed and respectively assigned into study group (n=36) and control group (n=38). In study group, the average level of serum 25(OH)D was significantly increased at month 12 compared with that at baseline [(22.87±7.30) µg/L vs. (18.15±7.48) µg/L,P<0.001]. However, no significant elevation of serum 25(OH)D was found in control group [(19.17±8.49) µg/L vs. (19.82±9.47) µg/L,P=0.466]. Furthermore, there was a significant decrease of modified Mayo score [-3(-4.75, -1.25) vs.-2(-3.25, 0), P=0.034] and a higher clinical remission rate (55.6% vs. 28.9%, P=0.020) at month 12 in study group than those in control group. In addition, according to the baseline level of serum 25(OH)D before mesalazine treatment, 74 UC patients were divided into vitamin D deficiency group (n=38, serum 25(OH)D<20 µg/L) and non-deficiency group (n=36, serum 25(OH)D≥20 µg/L). At month 12 in vitamin D deficiency group, patients with vitamin D3 supplementation had a greater decline in modified Mayo score [-4(-5.75, -2) vs.-2(-4, 0), P=0.048] and a higher clinical remission rate (60.0% vs. 22.2%, P=0.019) compared with those without. Conclusions: In patients with mild-to-moderate active UC receiving mesalazine treatment, vitamin D3 supplementation may improve the clinical efficacy, especially in patients with vitamin D deficiency.


Asunto(s)
Colitis Ulcerosa , Deficiencia de Vitamina D , Adulto , Colecalciferol/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Femenino , Humanos , Masculino , Mesalamina/uso terapéutico , Estudios Retrospectivos , Vitamina D/uso terapéutico , Deficiencia de Vitamina D/tratamiento farmacológico
4.
Zhonghua Yi Xue Za Zhi ; 102(19): 1417-1422, 2022 May 24.
Artículo en Chino | MEDLINE | ID: mdl-35599405

RESUMEN

Objective: To explore the changes of cerebral blood perfusion in patients with unilateral sudden sensorineural hearing loss (SSNHL) by using the three-dimensional pseudo-continuous arterial spin labeling (3D pCASL) technique. Methods: The clinical characteristics and ASL data of the 32 patients with unilateral SSNHL were retrospectively collected from November 2020 to June 2021 in Beijing Fuxing Hospital of Capital Medical University, among them, there were 7 males and 25 females, aged from 17 to 73 (44.9±14.4) years. According to the location of SSNHL, they were divided into the left SSNHL (L-SSNHL) group (18 cases) and the right SSNHL (R-SSNHL) group (14 cases). A total of 34 healthy volunteers, which including 14 males and 20 females, aged from 24 to 68 (46.2±14.4) years were enrolled from the local community. The parameter of cerebral blood flow (CBF) of each brain area was obtained using the CereFlow software. The Brainnetome Atlas software package based on MATLAB was used for visualization. The independent-samples t test was conducted to compare the difference of cerebral blood perfusion between the unilateral SSNHL group and healthy control (HC) group. Pearson correlation analysis was used to evaluate the correlation between changes in cerebral blood perfusion and clinical scale scores. Results: The CBF of left orbital gyrus part 5, left inferior temporal gyrus part 7, right orbital gyrus part 5, right inferior temporal gyrus part 1, right inferior temporal gyrus part 7, and right parahippocampal gyrus part 3 of the L-SSNHL group were higher than that in the HC group[(49.1±8.8) vs (31.6±10.9)ml·100g-1·min-1;(42.8±14.3) vs (27.1±13.6)ml·100g-1·min-1;(51.8±9.4) vs (27.2±11.2)ml·100g-1·min-1;(38.8±5.7) vs (28.0±9.2)ml·100g-1·min-1;(38.4±13.8) vs (23.6±10.3)ml·100g-1·min-1;(42.4±9.4) vs (30.1±12.6)ml·100g-1·min-1; all P<0.05]. The CBF of left superior frontal gyrus part 7 and left middle frontal gyrus part 3 of the L-SSNHL group were lower than that in the HC group[(48.2±7.9) vs (59.3±13.7)ml·100g-1·min-1;(46.4±10.3) vs (59.3±16.9)ml·100g-1·min-1;all P<0.05]. The CBF of left orbital gyrus part 5, right orbital gyrus part 5, right inferior temporal gyrus part 1, and right inferior temporal gyrus part 7 of the R-SSNHL group were higher than that in the HC group[(50.6±7.0) vs (31.6±10.9)ml·100g-1·min-1;(50.9±8.8) vs (27.2±11.2)ml·100 g-1·min-1;(38.0±7.2) vs (28.0±9.2)ml·100g-1·min-1;(35.7±8.5) vs (23.6±10.3)ml·100g-1·min-1;all P<0.05]; the CBF of right insular part 4 was lower than that in the HC group [(44.2±6.1) vs (54.4±11.3) ml·100 g-1·min-1, P=0.018]. In the L-SSNHL group, the CBF of left superior frontal gyrus part 7 and right orbital gyrus part 5 were negatively correlated with the VAS score(r=-0.83, -0.81, all P<0.05), and the CBF of right orbital gyrus part 5 was negatively correlated with the THI score(r=-0.75, P=0.013). There was no statistically significant correlation between the remaining differences in brain regions and clinical scale scores(all P>0.05). Conclusion: Changes in cerebral blood perfusion in multiple brain regions were found in patients with unilateral SSNHL by using the 3D pCASL technique.


Asunto(s)
Pérdida Auditiva Sensorineural , Imagen por Resonancia Magnética , Encéfalo , Circulación Cerebrovascular , Femenino , Humanos , Masculino , Perfusión , Estudios Retrospectivos , Marcadores de Spin
5.
Zhonghua Yi Xue Za Zhi ; 101(37): 3029-3032, 2021 Oct 12.
Artículo en Chino | MEDLINE | ID: mdl-34638196

RESUMEN

This retrospective analysis was conducted on clinical obtained DCE-MR images of 198 patients, age from 21 to 79 years(45.5±13.7). The CBAM-ResNet model was developed to perform the classification automatically at the image-level based on deep learning method using the pathological examination as the reference standard,then the classification result of each individual patient was obtained by ensemble learning. The proposed method can have an accuracy of 82.69% for correctly distinguishing between benign and malignant breast tumors at the slice-level based on CBAM-ResNet model and with a sensitivity of 85.67%.. After the voting mechanism is applied, the classification accuracy can reach up to 88.24% at the patient-level with a sensitivity of 87.50%. Our experimental results demonstrated the proposed approach have a high classification accuracy.


Asunto(s)
Inteligencia Artificial , Neoplasias de la Mama , Adulto , Anciano , Neoplasias de la Mama/diagnóstico por imagen , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
6.
Zhonghua Yi Xue Za Zhi ; 101(23): 1784-1790, 2021 Jun 22.
Artículo en Chino | MEDLINE | ID: mdl-34167278

RESUMEN

Objective: To compare the cerebral perfusion differences between the symptomatic patients and the asymptomatic patients with unilateral middle cerebral artery (MCA) severe stenosis or occlusion by using three post labeling delays (PLD) of the three-dimensional pseudo-continuous arterial spin labeling (pCASL) technique. Methods: The clinical characteristics and ASL data of the 27 patients with severe stenosis or occlusion of unilateral MCA (18 symptomatic, 9 asymptomatic) were prospectively enrolled from April 2018 to November 2019 in the Department of Radiology of China-Japan Friendship Hospital. There were 16 males and 11 females, age range from 29 to 85 (55±13) years. According to the symptoms, they were divided into symptomatic group (18 cases) and asymptomatic group (9 cases). The parameters of cerebral blood flow (CBF), mean cerebral blood flow (mCBF), arterial transit time (ATT) and arterial cerebral blood volume (aCBV) were obtained using the Cereflow software. One-way multivariate analysis of variance (one-way MANOVA) was used to compare the differences of cerebral perfusion parameters between symptomatic group and asymptomatic group, and between the affected side and the control side in the two groups. Two-way ANOVA was used to evaluate the effects of symptoms, hemisphere (affected and control side), PLD times (1.5, 2.0 and 2.5 s) and the interaction between the two factors. Results: The CBF of the affected leptomeningeal branch and perforating branch of MCA in symptomatic group was lower than that in asymptomatic group [(36.8±10.2) ml·100 g-1·min-1 versus (46.6±13.9) ml·100 g-1·min-1, F(1, 75)=13.279, P=0.000 49; (32.3±8.3) ml·100 g-1·min-1 versus (36.2±7.5) ml·100 g-1·min-1, F (1, 75)=4.065, P=0.047], and there was no interaction between the symptom and PLD [F(2, 75) =0.061, P=0.940]. In the symptomatic group, the CBF of the leptomeningeal branch and perforating branch of MCA in affected side was lower than that in control side [(36.8±10.2) ml·100 g-1·min-1 versus (43.7±10.0) ml·100 g-1·min-1, F(1, 102)=12.559, P=0.000 59; (32.3±8.3) ml·100 g-1·min-1 versus (36.4±8.0) ml·100 g-1·min-1, F(1, 102)=6.493, P=0.012]. In the symptomatic group, the CBF of leptomeningeal branch of MCA when PLD was 2.5 s was 7.34 ml·100 g-1·min-1, which were higher than that when PLD of 1.5 s (95%CI: 0.72-13.9, P=0.03). There was no interaction between PLD and hemisphere [F(2, 102) =0.307, P=0.736]. Conclusions: The collateral circulation in the blood supply area of MCA in asymptomatic patients with severe unilateral MCA stenosis or occlusion is more abundant than that in symptomatic patients. ASL can be an effective technique for evaluating the cerebral perfusion of collateral circulation in patients with severe stenosis or occlusion of MCA.


Asunto(s)
Imagen por Resonancia Magnética , Arteria Cerebral Media , Adulto , Anciano , Anciano de 80 o más Años , Circulación Cerebrovascular , China , Constricción Patológica , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Arteria Cerebral Media/diagnóstico por imagen , Marcadores de Spin
8.
Biomater Sci ; 6(3): 473-477, 2018 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-29436537

RESUMEN

Herein, the photosensitizer indocyanine green (ICG) is used to induce the self-assembly of antigens to form nanovaccines. Under near-infrared (NIR) laser irradiation, reactive oxygen species can be generated by nanovaccines to disrupt the membranes of endo/lysosomes, which helps to release antigens into the cytosol efficiently, thereby enhancing antigen cross-presentation and anti-cancer immunity. To the best of our knowledge, this study represents the first example of ICG as a biocompatible adjuvant to improve cancer vaccine efficacy.


Asunto(s)
Antígenos/química , Vacunas contra el Cáncer/química , Inmunoterapia/métodos , Verde de Indocianina/química , Neoplasias Experimentales/terapia , Fármacos Fotosensibilizantes/química , Animales , Antígenos/metabolismo , Antígenos/uso terapéutico , Vacunas contra el Cáncer/metabolismo , Vacunas contra el Cáncer/uso terapéutico , Línea Celular Tumoral , Humanos , Verde de Indocianina/farmacología , Ratones , Fármacos Fotosensibilizantes/farmacología , Multimerización de Proteína/efectos de los fármacos , Multimerización de Proteína/efectos de la radiación
9.
J Dairy Sci ; 101(2): 1601-1615, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29153512

RESUMEN

Differentiation and lipid metabolism of adipocytes have a great influence on milk performance, health, and feed efficiency of dairy cows. The effects of dietary long-chain fatty acids (FA) on adipogenesis and lipogenesis of dairy cows are often confounded by other nutritional and physiological factors in vivo. Therefore, this study used an in vitro approach to study the effect of dose and type of long-chain FA on adipogenesis and lipogenesis of bovine adipocytes. Stromal vascular cells were isolated from adipose tissue of dairy cows and induced into mature adipocytes in the presence of various long-chain FA including myristic, palmitic, stearic, oleic, or linoleic acid. When concentrations of myristic, palmitic, and oleic acids in adipogenic mediums were 150 and 200 µM, the induced mature adipocytes had greater lipid content compared with other concentrations of FA. In addition, mature adipocytes induced at 100 µM stearic acid and 300 µM linoleic acid had the greatest content of lipid than at other concentrations. High concentrations of saturated FA were more toxic for cells than the same concentration of unsaturated FA during the induction. When commitment stage was solely treated with FA, the number of differentiated mature adipocytes was greater for oleic and linoleic acids than other FA. When the maturation stage was treated with FA, the number of mature adipocytes was not affected, but the lipid content in adipocytes was affected and ranked oleic > linoleic > myristic > stearic > palmitic. In summary, this study showed that adipogenesis and lipogenesis of bovine adipocytes were differentially affected by long-chain FA, with unsaturated FA more effective than saturated FA.


Asunto(s)
Adipocitos/efectos de los fármacos , Bovinos/fisiología , Ácidos Grasos/clasificación , Ácidos Grasos/farmacología , Lipogénesis/efectos de los fármacos , Adipocitos/fisiología , Animales , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Metabolismo de los Lípidos/efectos de los fármacos , Leche/metabolismo
10.
Zhonghua Yi Xue Za Zhi ; 97(27): 2081-2086, 2017 Jul 18.
Artículo en Chino | MEDLINE | ID: mdl-28763879

RESUMEN

Objective: To analysis the change of brain functional activity in the left and right peripheral facial paralysis by using resting-state functional magnetic resonance imaging (R-fMRI) of fraction amplitude of low frequency fluctuation(fALFF) measurement technique, and research the abnormal brain region with different side patients whether there are differences. Methods: A total of 43 patients with peripheral facial paralysis patients (patient groups, divided into left / right two subgroups) and 21 healthy volunteers (control group) in this study.Resting-state fMRI were acquired for each volunteer and patient. The fALFF approach was used to compare the peripheral facial paralysis groups to healthy group.Functional analysis was performed with brain function analysis software REST and DPARSFA , and then analysis the difference of two groups of patients and control group in two sample t test.At the same time, the correlation analysis between fALFF parameters map of the left and right side of two groups of patients and corresponding facial nerve grading TFGS score.Ultimately obtain a statistically significant brain regions. Results: Compared to healthy group, the decreased fALFF areas in the left side facial paralysis were showed in the right superior temporal gyrus , the pole of the right temporal, right middle temporal gyrus, the left occipital gyrus, and left medial cingulate gyrus, left paracentral lobule, and the left supplementary motor area; while the increased brain regions have the right superior frontal gyrus, right middle frontal gyrus, the right precentral gyrus, bilateral inferior temporal gyrus and middle temporal gyrus.Compared to healthy group, the decreased fALFF areas in the right side facial paralysis were showed in the right inferior temporal gyrus and fusiform gyrus, the left inferior occipital gyrus, the left superior parietalgyrus, the left inferior parietalgyrus, left precuneus, left paracentral lobule, the left supplementary motor area; while the increased brain regions have the left Calcarine, right lingual gyrus, corpus callosum, right medial cingulum gyrus.In the left facial paralysis group TFGS score was positively correlated with brain regions have left middle frontal gyrus, left precuneus and left cuneus, while the negatively related brain area on the right lingual gyrus.In the right facial paralysis groups TFGS score was positively correlated with brain areas have right inferior temporal gyrus and middle temporal gyrus, left inferior parietalgyrus; while the negatively correlated brain area on the left superior temporal gyrus, the right medial frontal gyrus. Conclusion: The left and right side facial paralysis patient's mood and motor function integration mechanism may be different, and the patient's emotional and psychological changes may be associated with disease severity.


Asunto(s)
Parálisis Facial/diagnóstico por imagen , Imagen por Resonancia Magnética , Encéfalo , Mapeo Encefálico , Humanos
11.
Appl Opt ; 45(23): 5871-6, 2006 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-16926874

RESUMEN

We have computed the transmittances of four types of cathode--Yb/Au, Al/Au, Yb/Ag, and Al/Ag double layers--and the light extraction efficiencies of the top-emission organic light-emitting diodes with these cathodes, respectively, based on the characteristic matrix method and the dissipation spectrum model. Computations show that the Yb/Au cathode has a markedly higher transmittance than the other three types of cathode when the Yb and Au thicknesses in the Yb/Au cathode are, respectively, equal to the Al (or Yb) and Au (or Ag) thicknesses in the other three types of cathode. The power lost to the Yb/Au cathode due to the surface plasmon polaritons is the lowest, and hence the device with the Yb/Au cathode has the highest extraction efficiency. The transmittances for the four cathodes are also measured experimentally.

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