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1.
J Nanosci Nanotechnol ; 21(10): 5319-5328, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33875125

RESUMO

Transition metal and nitrogen co-doped carbon-based catalysts (TM-N-C) have become the most promising catalysts for Pt/C due to their wide range of sources, low cost, high catalytic activity, excellent stability and strong resistance to poisoning, especially Fe-N-C metal-organic frameworks (MOFs), which are some of the most promising precursors for the preparation of Fe-N-C catalysts due to their inherent properties, such as their highly ordered three-dimensional framework structure, controlled porosity, and tuneable chemistry. Based on these, in this paper, different iron sources were added to synthesis a sort of zeolitic imidazole frameworks (ZIF-8). Then the imidazole salt in ZIF-8 was rearranged into high N-doped carbon by high-temperature pyrolysis to prepare the Fe-N-C catalyst. We studied the physical characteristics of the catalysts by different iron sources and their effects on the catalytic properties of the oxygen reduction reaction (ORR). From the point of morphology, various iron sources have a positive influence on maintaining the morphology of ZIF-8 polyhedron. Fe-N/C-Fe(NO3)3 has the same anion as zinc nitrate, and can maintain a polyhedral morphology after high-temperature calcination. It had the highest ORR catalytic activity compared to the other four catalyst materials, which proved that there is a certain relationship between morphology and performance. This paper will provide a useful reference and new models for the development of high-performance ORR catalysts without precious metals.

2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(6): 2033-2038, 2020 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-33283738

RESUMO

OBJECTIVE: To analyze the molecular pathogenesis by analysis of phenotype and gene mutation in families with hereditary coagulation factor V (FⅤ) defect caused by complex heterozygous mutation. METHODS: Plasma pro-thrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), FⅤ procoagulant activity (FⅤ∶C), FⅤ antigen (FⅤ∶Ag), and other related coagulation indexes were detected in the proband and his family members (3 generations 10 people). Using DNA direct sequencing to analyze all exons, flanks, 5' and 3' untranslated regions of F5 genes and the corresponding mutation site regions of family members, the mutation site was confirmed by reverse sequencing.The conservation of mutant amino acids was analyzed by ClustalX-2.1-win software. The PROVEAN and MutationTaster online bioinformatics software were used to predict the effect of mutation on protein function. Protein model and amino acid interaction at mutation sites was analyzed by Swiss-pdbviewer software. RESULTS: The PT and APTT of the proband were significantly prolonged compared with healthy controls (34.2 vs 13.2 s and 119.3 vs 36.0 s), while FⅤ∶C and FⅤ∶Ag extremely reduced (3% and 6%). The PT and APTT of the second-born, the third son, daughter, and grandson of the proband were slightly prolonged, and the FⅤ∶C and FⅤ∶Ag decreased to varying degrees. The related coagulant parameters of other family members were within normal range. Genetic analysis revealed that the proband had a c.911G>A heterozygous missense mutation on the exon 6 lead to p.Gly276Glu, and a c.5343C>G heterozygous missense mutation on the exon 16 lead to p.Ser1781Arg of the proband. The second-born, the third son, and grandson of the proband carry p.Gly276Glu heterozygotes, and the daughter carries p.Ser1781Arg heterozygotes, while the other family members were wild-type. The results of conservative analysis indicated that p.Gly276 and p.Ser1781 were highly conserved in homologous species. The two bioinformatics software predicted the same results, PROVEAN (score -6.214 and -12.79) indicated that the compound heterozygous mutation was a harmful mutation; MutationTaster (score 0.976 and 0.999) suggested that these mutations might cause corresponding disease. p.Gly276Glu protein model analysis showed that, the Glu side chain was prolonged and the molecular weight became larger, which would increase the steric hindrance between it and the surrounding amino acids, affect the normal local folding of the FⅤ protein, and eventually lead to the decrease of protein activity and content. This paper can not provide analysis of the spatial structure of p.Ser1781Arg mutant protein because of the lack of X ray 3 D structure file of FⅤ exon 16. CONCLUSION: The new compound heterozygous mutations (p.Gly276Glu and p.Ser1781Arg) identified in this study are the main reasons for the decrease in the FⅤ level of the family, among which p.Ser1781Arg is rarely reported at home and abroad.


Assuntos
Fator V , Família , Fator V/genética , Genótipo , Heterozigoto , Humanos , Mutação , Linhagem , Fenótipo
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 47(2): 129-34, 2013 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-23719103

RESUMO

OBJECTIVE: To develop the national neglect norms for urban primary school students in China. METHODS: According to multi-stage stratified cluster sampling principle, 24 cities of 13 provinces (municipalities) in China were selected during December 1 to 31, 2008. A total of 1491 students in grade 1 - 3 and 2236 students in grade 4 - 6 were selected. Questionnaire was designed by authors and the final norms were determined through several statistical analysis methods, such as item analysis method, factor analysis method, reliability analysis method. The reliability analysis and validity analysis were used to test the stability and reliability of the norms. The evaluation criteria of the scale was determined by the percentile method, then the initial development of the norm was completed. RESULTS: The two questionnaires of grade 1 - 3 and grade 4 - 6 students consisted of 55 and 57 items, respectively, whose item loadings were ranged from 0.301 to 0.687 and 0.321 to 0.730, which met the statistical requirements. For grade 1 - 3 students, the scale's total Cronbach α coefficients was 0.914, the total split-half reliability coefficients was 0.896, the Cronbach α coefficients of four level was above 0.737 except medical and social neglect, split-half reliability was ranged from 0.461 to 0.757; for grade 4-6 students, the scale's total Cronbach α coefficients was 0.916, split-half reliability was 0.883, except social neglect, the Cronbach α coefficients of other level was ranged 0.457 to 0.856, split-half reliability was ranged from 0.500 to 0.798. The total neglect cut-off score of the two scales grade 1-3 and 4-6 were 125 and 155, respectively. CONCLUSION: The structure of two norms was reasonable. The scales have good stability and reliability.


Assuntos
Maus-Tratos Infantis/prevenção & controle , Estudantes , Inquéritos e Questionários , Criança , Maus-Tratos Infantis/estatística & dados numéricos , China/epidemiologia , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Instituições Acadêmicas
4.
Zhonghua Yan Ke Za Zhi ; 48(7): 598-603, 2012 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-22943863

RESUMO

OBJECTIVES: To investigate whether aquaporin 4 (AQP4) gene can affect the activation of glial cells and cause the injury of retina of chronic high intraocular pressure mice models, and to discuss its possible mechanism. METHODS: Experimental study. The chronic high intraocular pressure models were established by burning the scleral venous of the right eye, which as the experiment group, and the left eye without any treatment as the control group. The intraocular pressure (IOP) was measured by rebound tonometer. Selected each of the successful model of chronic high intraocular pressure male AQP4 knockout mice (AQP-/-) and their wild-type (WT) male mice 40, divided the two type of mice into five groups after scleral venous burn according to the time of establishing models (24 h, 3 d, 1 w, 2 w, 4 w after scleral venous burn), 8 mouse in each group. And then producing the paraffin sections of mouse eye. Immunohistochemical staining methods was used to observe the expression of the glial fibrillary acid protein (GFAP) in retina glial cells, and observe the expression of the AQP4 in the retina of the WT mouse. Image was acquired under the fluorescence microscopy. The intraocular pressure was analyzed by t-test. RESULTS: After scleral venous burn (24 h, 3 d, 1 w, 2 w, 4 w), there were significant difference (t = 6.66 - 18.08, all P value < 0.05) in the IOP of the AQP4-/- mice (11.30 ± 1.59, 11.20 ± 1.15, 10.60 ± 1.53, 10.75 ± 1.45, 10.45 ± 1.39) and WT mice (11.50 ± 2.56, 11.25 ± 1.65, 10.75 ± 1.33, 10.60 ± 1.33, 10.40 ± 1.19) between the experimental groups and control groups (6.60 ± 0.94, 6.35 ± 0.99, 6.55 ± 0.94, 6.45 ± 0.99, 6.50 ± 0.94 and 6.60 ± 1.05, 6.50 ± 0.89, 6.40 ± 1.09, 6.30 ± 1.13, 6.50 ± 1.05). Since 24 hours after the scleral venous burn, the expression of GAFP of the two type mice began to increase and reached to peak at 1 week after burning. This peak of WT mice was more obvious than that of AQP4-/- mice. The concentration of GAFP began to decrease at 2 weeks after burning and reached to bottom at 4 weeks later. To the WT mice, the expression of AQP4 was remarkable higher in experimental group than that in control group at 1 week after the scleral venous burn. The expression of AQP4 was related to the expression of GAFP in high intraocular pressure of WT mice at 1 w, 2 w, and 4 w after the scleral venous burn. CONCLUSIONS: The chronic high intraocular pressure models can be established successfully by burning the scleral venous. AQP4 gene can affect the activation of the glial cells in chronic high intraocular pressure mice and lead to the injury of retina.


Assuntos
Aquaporina 4/genética , Neuroglia/citologia , Hipertensão Ocular , Retina/citologia , Animais , Proteína Glial Fibrilar Ácida/metabolismo , Pressão Intraocular , Masculino , Camundongos , Camundongos Knockout , Hipertensão Ocular/metabolismo , Hipertensão Ocular/patologia
5.
Zhonghua Liu Xing Bing Xue Za Zhi ; 33(1): 54-6, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22575111

RESUMO

OBJECTIVE: To develop the National Norms of Negligence (NNN) for rural children aged 0 to 35 months. METHODS: According to multi-stage stratified cluster sampling principle, 10 provinces or municipalities (Jilin, Shanxi, Shanxi, Beijing, Anhui, Jiangsu, Hunan, Hubei, Yunnan, Chongqing) in China were selected. A national research group was formed collaboratively. A questionnaire was designed by ourselves. According to several statistical analysis methods, such as item, factor and reliability analysis etc. we determined the norm. The evaluation criteria of the scale were determined by percentile method. Finally, the reliability and validity of the norm were evaluated. RESULTS: In total, 2310 children were surveyed, in which the effective sample were 2227, with an effective rate as 96.4%. The scale consisted of 6 neglected dimensions and 65 items in total. The total Cronbach's a coefficient of the scale was 0.903, with the split-half reliability coefficient as 0.829, the parallel reliability as 0.720 and the re-test reliability as 0.678, respectively. The total neglect cut-off score of this scale was 139. CONCLUSION: The scale seemed to have perfect stability and reliability and all the statistical indicators met the psychometric demands.


Assuntos
Maus-Tratos Infantis/diagnóstico , Pré-Escolar , China , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Padrões de Referência , Reprodutibilidade dos Testes , População Rural , Inquéritos e Questionários
6.
Zhonghua Yu Fang Yi Xue Za Zhi ; 46(1): 16-21, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22490133

RESUMO

OBJECTIVE: To develop the national neglect norms for rural children aged 3 to 6 years, which are suitable for Chinese situations. METHODS: According to the multi-stage stratified cluster sampling principle, 84 towns of 10 provinces or municipalities were selected in China. Children aged 3 to 6 years were surveyed in November 2010, the sample of analysis were 3240 (of whom males were 49.6% (1608/3240) and the Han nationality were 93.3% (3023/3240)). Questionnaire was designed by authors and deleted items that did not meet the requirements through several statistical analysis methods, such as item analysis method, factor analysis method, reliability analysis method. The reliability analysis and validity analysis were used to test the stability and reliability of the norm. The evaluation criteria of the scale was determined by the percentile method, then the initial development of the norm completed. RESULTS: After deleting inappropriate items by statistical processing, finally, the scale consisted of 57 items, and included 6 neglected dimensions (physical neglect, emotional neglect, educational neglect, safe neglect, medical neglect and social neglect). Its item loadings ranged from 0.359 to 0.789, which met the statistical requirements. The scale's total Cronbach α coefficients 0.904, the total split-half reliability coefficients were 0.820, the 6 neglect dimensions' Cronbach α coefficients ranged from 0.620 to 0.815, the 6 neglect dimensions' split-half reliability coefficients ranged from -0.034 to 0.789, the scale's parallel reliability were 0.785 and it's re-test reliability were 0.613. After construct validity, external validity and content validity testing, the result showed that this scale could effectively reflect the real neglected status of children investigated. The total neglect cut-off score of this scale were 121. CONCLUSION: The scale has good stability and reliability. And it adapts Chinese conditions and it's convenient to operate.


Assuntos
Maus-Tratos Infantis/diagnóstico , Testes Psicológicos , Inquéritos e Questionários , Maus-Tratos Infantis/prevenção & controle , Pré-Escolar , China , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , População Rural , Estudos de Amostragem , Inquéritos e Questionários/normas
7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 46(1): 28-32, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22490135

RESUMO

OBJECTIVE: To explore the status of child neglect among urban areas children and adolescents aged 3 - 17 years in China. METHODS: Using multi-stage stratified cluster sampling method, 8001 children and adolescents were recruited from 30 cities of 14 provinces in December 2008. The investigation was carried based on The 3 - 6 years old children Neglect Norms of city in China and The 6 - 17 years old children Neglect Norms of city in China. SPSS 13.0 was employed for analyzing neglect rate and degree for group of areas, age, sex and neglect type (including neglect of physical, emotional, educational, medical, safety and social). RESULTS: The degrees of child neglect for urban children aged 3 - 6 (children aged 6 were not in school), 6 - 8 (children aged 6 were school children), 9 - 11, 12 - 14 and 15 - 17 were 42.2 ± 6.9, 42.8 ± 8.4, 42.1 ± 9.1, 46.4 ± 9.2 and 49.7 ± 8.4(P < 0.05), the neglect rates were 28.0% (326/1163), 28.8% (431/1496), 27.2% (543/1962), 22.4% (373/1664) and 32.8% (563/1716) (P < 0.05), respectively. There were differences in six neglect types for each group; the neglect degrees and rates were high in the group aged 12 - 14 and 15 - 17 (46.4 ± 9.2 and 49.1 ± 8.4, 22.4% (373/1664) and 32.8% (563/1716), respectively); for each neglect type, the neglect degree of children aged 15 - 17 were highest (52.8 ± 8.0, 47.3 ± 11.6, 49.5 ± 10.8, 42.4 ± 10.3, 52.2 ± 16.0, 56.0 ± 10.1). The degree and rate of neglect in West were highest, Middle was next, the East was lowest (the neglect degrees were 45.4 ± 9.1, 45.0 ± 9.3 and 44.0 ± 8.8, P < 0.05;the rates were 30.7% (1340/4361), 25.0% (756/3024) and 21.2% (131/616), P < 0.05). Degree and rate of child neglect for children without siblings were lower than children with siblings (the neglect degrees were 44.2 ± 9.0 and 47.6 ± 9.1, P < 0.01; the rates were 26.1% (1572/6017) and 33.0% (655/1984), P < 0.01). Neglect degree of school children aged 6 years old (43.1 ± 7.3) was higher than children not in school (40.7 ± 7.8) (P < 0.01), but neglect rate was lower (the rates were 35.4% (60/169) and 21.3% (84/394), P < 0.01). CONCLUSION: Neglect degree and rate of urban children and adolescents aged 3 - 17 years in China were both high, and neglect deserved more attentions.


Assuntos
Maus-Tratos Infantis/estatística & dados numéricos , Adolescente , Criança , Maus-Tratos Infantis/prevenção & controle , Pré-Escolar , China , Estudos Transversais , Feminino , Humanos , Masculino , População Urbana
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