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1.
Journal of Biomedical Engineering ; (6): 409-417, 2023.
Artigo em Chinês | WPRIM | ID: wpr-981557

RESUMO

High-frequency steady-state asymmetric visual evoked potential (SSaVEP) provides a new paradigm for designing comfortable and practical brain-computer interface (BCI) systems. However, due to the weak amplitude and strong noise of high-frequency signals, it is of great significance to study how to enhance their signal features. In this study, a 30 Hz high-frequency visual stimulus was used, and the peripheral visual field was equally divided into eight annular sectors. Eight kinds of annular sector pairs were selected based on the mapping relationship of visual space onto the primary visual cortex (V1), and three phases (in-phase[0º, 0º], anti-phase [0º, 180º], and anti-phase [180º, 0º]) were designed for each annular sector pair to explore response intensity and signal-to-noise ratio under phase modulation. A total of 8 healthy subjects were recruited in the experiment. The results showed that three annular sector pairs exhibited significant differences in SSaVEP features under phase modulation at 30 Hz high-frequency stimulation. And the spatial feature analysis showed that the two types of features of the annular sector pair in the lower visual field were significantly higher than those in the upper visual field. This study further used the filter bank and ensemble task-related component analysis to calculate the classification accuracy of annular sector pairs under three-phase modulations, and the average accuracy was up to 91.5%, which proved that the phase-modulated SSaVEP features could be used to encode high- frequency SSaVEP. In summary, the results of this study provide new ideas for enhancing the features of high-frequency SSaVEP signals and expanding the instruction set of the traditional steady state visual evoked potential paradigm.


Assuntos
Humanos , Potenciais Evocados Visuais , Interfaces Cérebro-Computador , Voluntários Saudáveis , Razão Sinal-Ruído
2.
Journal of Biomedical Engineering ; (6): 18-22, 2016.
Artigo em Chinês | WPRIM | ID: wpr-357858

RESUMO

Intraocular pressure detection has a great significance for understanding the status of eye health, prevention and treatment of diseases such as glaucoma. Traditional intraocular pressure detection needs to be held in the hospital. It is not only time-consuming to doctors and patients, but also difficult to achieve 24 hour-continuous detection. Microminiaturization of the intraocular pressure sensor and wearing it as a contact lens, which is convenient, comfortable and noninvasive, can solve this problem because the soft contact lens with an embedded micro fabricated strain gauge allows the measurement of changes in corneal curvature to correlate to variations of intraocular pressure. We fabricated a strain gauge using micro-electron mechanical systems, and integrated with the contact lens made of polydimethylsiloxane (PDMS) using injection molding. The experimental results showed that the sensitivity was 100. 7 µV/µm. When attached to the corneal surface, the average sensitivity of sensor response of intraocular pressure can be 125.8 µV/mm Hg under the ideal condition.


Assuntos
Humanos , Lentes de Contato Hidrofílicas , Dimetilpolisiloxanos , Glaucoma , Pressão Intraocular , Tonometria Ocular
3.
Chinese Medical Ethics ; (6): 690-693, 2016.
Artigo em Chinês | WPRIM | ID: wpr-496128

RESUMO

Mental Health Law has specify the mental disorder patients’ informed consent right,but in practice, the problems,the mental health status of patients, namely the families’ right of subrogation exercise,“loss of self-control or deny having mental disorder”, have prevented the exercising of informed consent right. Therefore,it is necessary to effectively solve this plight of rebuilding a harmonious relationship between doctors and patients,estab-lishing mentally disordered patients’ right to advance directives, especially choosing the instrument of assessing the individual’ s capacity to consent.

4.
Chinese Journal of Behavioral Medicine and Brain Science ; (12): 755-757, 2013.
Artigo em Chinês | WPRIM | ID: wpr-441908

RESUMO

Objective To conduct a preliminary examination of the factor structure and the reliability and validity of a revised Chinese version of the State-Trait Anxiety Inventory-Form Y (STAI-Y) by using the large sample of migrant children.Methods Perform Exploratory Factor Analysis with half of the data (n =5477) from a large-scale questionnaire survey of students in Grades 4-9 at 58 schools for migrants in Beijing,then conduct Confirmatory Factor Analysis with the other half (n =5476).Results The results of state anxiety and trait anxiety both showed two factors.However,the indicators of trait anxiety were not ideal as seen from the following:the total explained variance was 39.22%,the relationship between the factors and items was not in accordance with the original English version,and the correlation between the two factors was unstable in the different samples (r =-0.17,P < 0.001 ; r =-0.06,P < 0.001).In addition,the factor loading of items 24 ( I wish I could be as happy as others) was low.Conclusion The state anxiety portion of this revised Chinese version of the STAI-Y is structured by the factors state anxiety present and state anxiety absent,and with good reliability and validity as well.Nevertheless,the trait anxiety portion of this revised Chinese version of the STAI-Y is structured by the factors trait anxiety present and trait anxiety absent,it shows unstable reliability and validity.

5.
Chinese Journal of Pancreatology ; (6): 413-416, 2011.
Artigo em Chinês | WPRIM | ID: wpr-417600

RESUMO

ObjectiveTo study the expression of p27 and its relationship with CpG island methylation phenotype (CIMP) in insulinoma.MethodsExpression of p27 was tested in 27 insulinoma tissues and 11 paired control tissues by immunohistochemistry staining.CpG island methylation of p16,MLH1,RAR-β,MGMT,THBS1 (CIMP) was detected in 27 insulinoma tissues and 11 paired cantrol tissues by methylation specific PCR (MSP).The data of p27 and CIMP expression were correlated with the clinicopathological characteristics.ResultsThe positive expression rate of p27 in insulinoma tissues was significantly lower than that in paired control tissues (48% vs 91%,P =0.008).High rate of CIMP occurrence in insulinoma tissues was 33% (9/27),while it was 18% (2/11) in paired control tissues,and difference between the two groups was not statistically significant ( P =0.350 ).The methylation of MGMT was reversely associated with p16 methylation ( P =0.004).p27 expression in insulinoma tissues was reversely associated high rate of CIMP occurrence but it was not statistically significant ( P =0.420).Neither the expression of p27 nor the occurrence of CIMP was associated with the clinicopathological features.ConclusionsDown-regulation of p27 and high rate of CIMP occurred in insulinomas,suggesting that the inactivation of p27 and epigenetic alterations of several genes might contribute to the carcinogenesis of insulinoma.

6.
Chinese Journal of Tissue Engineering Research ; (53)2007.
Artigo em Chinês | WPRIM | ID: wpr-588692

RESUMO

AIM: To study the effect of the radix sophorae flavescentis on cellular immunity in rats with Pneumocystis Carinii Pneumonia (PCP) induced by long-term use of immunosuppressant, and explore the action of traditional Chinese medicine for the immunological regulation and infectious prevention after organ transplantation. METHODS: The experiment was conducted at Department of Pathobiology, Jilin Medical College from May 2005 to March 2006. Forty adult healthy female SD rats were selected from Harbin Medical University (Certification: 02473146) and randomly divided into experiment group and control group, with 20 rats in each. The model of PCP was set up by glucocorticoid injection subcutaneously to SD rats (25 mg once, 2 times/week). The mixture of sophorae flavescentis was given to stomach with tube in experiment group (3 mL/kg, 2 times/day), and was consisted of radix sophorae flavescentis, ash bark, amur cork-tree, malt, milkvetch root and danshen root. Six weeks later, all the rats were anesthetized and broncholveolar lavage fluids were collected.①Alveolar washing fluid was concentrated 10 times and the levels of the soluble interleukin-2 receptor (sIL-2R) were examined by double antigen sandwich ELISA.②Blood was sampled from rat eyes and the count of lymphocytes in peripheral blood were detected.③The percentages of CD3+ and CD4+ subgroups were assessed with erythrocyte chaplet kit sensitized by antigen. RESULTS: All 40 rats were involved in the result analysis without drop.①The count of lymphocytes in peripheral blood in experiment group was significantly higher than that in control group (5.1?1.3)%, (0.8?0.3)%, P

7.
Chinese Journal of Tissue Engineering Research ; (53): 2978-2002.
Artigo em Chinês | WPRIM | ID: wpr-555587

RESUMO

Objective To explore the treatment effect of human growth factor (NGF) on vascular dementia. Method 47 cases with vascular dementia were randomly divided into two groups (study and control). The study group (24 cases) were treated with NGF, the control group (23 cases) were treated with ordinary medicines.Results The intelligence and cognitive ability in the study group were obviously higher than those in the control group (P<0.01). Conclusion Compared with other methods, NGF has a significant curative effect.

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