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1.
Phys Chem Chem Phys ; 26(11): 8695-8703, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37947451

RESUMO

Zintl-phase materials have attracted significant research interest owing to the interplay of magnetism and strong spin-orbit coupling, providing a prominent material platform for axion electrodynamics. Here, we report the single-crystal growth, structure, magnetic and electrical/thermal transport properties of the antiferromagnet layer Zintl-phase compound ß-EuIn2As2. Importantly, the new layered structure of ß-EuIn2As2, in rhombohedral (R3̄m) symmetry, contains triangular layers of Eu2+ ions. The in-plane resistivity ρ(H, T) measurements reveal metal behavior with an antiferromagnetic (AFM) transition (TN ∼ 23.5 K), which is consistent with the heat capacity Cp(H, T) and magnetic susceptibility χ(H, T) measurements. Negative MR was observed in the temperature range from 2 K to 20 K with a maximum MR ratio of 0.06. Unique 4f7J = S = 7/2 Eu2+ spins were supposed magnetically order along the c-axis. The Seebeck coefficient shows a maximum thermopower |Smax| of about 40 µV K-1. The kink around 23 K in the Seebeck coefficient originates from the effect of the antiferromagnetic phase on the electron band structure, while the pronounced thermal conductivity peak at around 10 K is attributed to the phonon-phonon Umklapp scattering. The results suggest that the Eu2+ spin arrangement plays an important role in the magnetic, electrical, and thermal transport properties in ß-EuIn2As2, which might be helpful for future potential technical applications.

2.
Phys Rev Lett ; 128(8): 085003, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35275672

RESUMO

High-ß_{θe} (a ratio of the electron thermal pressure to the poloidal magnetic pressure) steady-state long-pulse plasmas with steep central electron temperature gradient are achieved in the Experimental Advanced Superconducting Tokamak. An intrinsic current is observed to be modulated by turbulence driven by the electron temperature gradient. This turbulent current is generated in the countercurrent direction and can reach a maximum ratio of 25% of the bootstrap current. Gyrokinetic simulations and experimental observations indicate that the turbulence is the electron temperature gradient mode (ETG). The dominant mechanism for the turbulent current generation is due to the divergence of ETG-driven residual flux of current. Good agreement has been found between experiments and theory for the critical value of the electron temperature gradient triggering ETG and for the level of the turbulent current. The maximum values of turbulent current and electron temperature gradient lead to the destabilization of an m/n=1/1 kink mode, which by counteraction reduces the turbulence level (m and n are the poloidal and toroidal mode number, respectively). These observations suggest that the self-regulation system including turbulence, turbulent current, and kink mode is a contributing mechanism for sustaining the steady-state long-pulse high-ß_{θe} regime.

3.
Fa Yi Xue Za Zhi ; 35(1): 23-29, 2019 Feb.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-30896115

RESUMO

OBJECTIVES: To analyze the polymorphism of 71 SNP loci on Y chromosome in Han population of Northwest China, to assess its forensic application value, and to screen out Y-SNP loci for forensic examination of Han population in East, South, and Northwest China based on the integration of previous research results. METHODS: Multiplex polymerase chain reaction (PCR) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) were performed on 71 Y-SNP loci of 202 unrelated Han male individuals in Northwest China. Gene diversity (GD) and haplotype diversity (HD) values were calculated, and then Y-SNP loci of Han population in East, South, and Northwest China were screened with the combination of data from previous research. RESULTS: Among the detected 71 loci, 67 loci were polymorphic in the Northwest Han male population, with GD values 0.010 0-0.502 2. There were 22 and 25 loci with a moderate (0.2≤GD<0.3) and high (GD≥0.3) amount of genetic information, respectively. There were 26 loci for the Han communities in Northwest, South, and East China. CONCLUSIONS: Y-SNP loci are potential in paternity testing and individual identification, as well as the judgement of population distribution and migration.


Assuntos
Povo Asiático , Cromossomos Humanos Y , Polimorfismo Genético , Povo Asiático/genética , China , Frequência do Gene , Genética Populacional , Haplótipos , Humanos , Masculino
4.
Fa Yi Xue Za Zhi ; 33(3): 239-243, 2017 Jun.
Artigo em Zh | MEDLINE | ID: mdl-29230986

RESUMO

OBJECTIVES: To analyse the genetic polymorphisms of 66 biallelic genetic markers on Y chromosome in Eastern Chinese Han population, and evaluate their values in forensic application. METHODS: Genotyping of 66 biallelic genetic markers on Y chromosome was studied in 205 unrelated males of Eastern Chinese Han population by multiplex PCR combined matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The allele frequencies on the loci to be tested were calculated by direct counting method, and the gene diversity (GD) and haplotype diversity (HD) were calculated by corresponding formulas. The haplotypes of this system were tested by software Arlequin v3.5.2.2 and the comparison of population genetics were analyzed. RESULTS: A total of 60 biallelic genetic markers on Y chromosome were polymorphic in males of Eastern Chinese Han population, and the ranges of GD were from 0.038 5 to 0.501 9. Eighty-five different haplotypes were observed and the HD was 0.970 3. The differences of partial SNP loci between the Han population of Eastern China and that of Xinjiang and Guangdong were statistically significance. CONCLUSIONS: Sixty biallelic genetic markers and the detection system can complementally provide genetic information in kinship testing and individual identification. The MALDI-TOF-MS technology is able to type biallelic genetic markers.


Assuntos
Povo Asiático/genética , Cromossomos Humanos Y/genética , Marcadores Genéticos/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Polimorfismo de Nucleotídeo Único/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Povo Asiático/etnologia , China , Frequência do Gene , Variação Genética , Genética Populacional , Genótipo , Haplótipos/genética , Humanos , Masculino
5.
Zhonghua Wai Ke Za Zhi ; 54(3): 206-11, 2016 Mar 01.
Artigo em Zh | MEDLINE | ID: mdl-26932890

RESUMO

OBJECTIVE: To study the risk factors for postoperative hypoparathyroidism or hypocalcemia. METHODS: Totally 414 patients with thyroid diseases who underwent total or near total thyroidectomy at Department of Head and Neck Surgery, Peking University Cancer Hospital and Institute from June 2007 to June 2014 were studied retrospectively. There were 119 male and 295 female patients with a median age of 47 years. The clinical and pathological features that related to post-operative hypoparathyroidism were studied by χ(2) test and multivariate Logistic regression analysis. RESULTS: Of the 414 patients, 36.2% developed transient hypocalcemia, 36.5% developed transient hypoparathyroidism, 2.2% developed permanent hypoparathyroidism. In regression analysis, unilateral or bilateral center lymph node dissection were associated with mild transient hypocalcemia after surgery (OR=2.366, P=0.022; OR=5.216, P=0.000); unilateral or bilateral center lymph node dissection as well as surgical options were significant risk factors for severe transient hypocalcemia (OR=4.029, P=0.001; OR=8.384, P=0.000; OR=2.073, P=0.017) and hypoparathyroidism (OR=1.755, P=0.040; OR=4.144, P=0.000; OR=2.287, P=0.000). The parathyroid hormone concentration on postoperative day 1 was an independent risk factor for permanent hypoparathyroidism (OR=2.011, P=0.014). The concentration of parathyroid hormone threshold <5.28 ng/L was a predictor to permanent hypoparathyroidism with accuracy of 95.0%. CONCLUSIONS: Bilateral center lymph node dissection is a risk factor of permanent hypoparathyroidism in patients received total thyroidectomy should be taken thoughtfully. The parathyroid hormone concentration on postoperative day 1 provides better prediction for persistent hypoparathyroidism.


Assuntos
Hipocalcemia/etiologia , Hipoparatireoidismo/etiologia , Tireoidectomia/efeitos adversos , Feminino , Humanos , Excisão de Linfonodo/efeitos adversos , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Estudos Retrospectivos , Fatores de Risco
7.
Artigo em Zh | MEDLINE | ID: mdl-30704174

RESUMO

This article focuses on the controversial issues in the diagnosis and treatment of thyroid cancer. Several commonly used molecular tests, especially gene mutation and fusion detection, in the preoperative diagnosis of thyroid nodules and the prognosis evaluation of thyroid cancer are introduced. For the thyroid nodules with uncertain indeterminate cytology, different molecular screening methods have their own advantages and disadvantages. Among them, DNA detection, especially multi-gene molecular testing based on next-generation sequencing has better sensitivity and specificity. Besides being used in diagnosis, it can also detect gene mutations related to tumor prognosis, such as BRAF(V600E) mutation and TERT promoter mutation, which is increasingly widespread and accepted.


Assuntos
Mutação/genética , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Nódulo da Glândula Tireoide/diagnóstico , Biópsia por Agulha Fina , Análise Mutacional de DNA , Humanos , Prognóstico , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas B-raf/genética , Sensibilidade e Especificidade , Análise de Sequência de DNA/métodos , Telomerase/genética , Nódulo da Glândula Tireoide/genética
8.
Artigo em Zh | MEDLINE | ID: mdl-30704165

RESUMO

Objective: To investigate the diagnostic performance of fine-needle aspiration (FNA) cytology for the detection of lateral lymph node metastases in patients with papillary thyroid carcinoma (PTC). Methods: A total of 109 lateral lymph nodes with suspicious metastases from 85 patients were retrospectively subjected to FNAC, fine-needle aspiration thyroglobulin measurement (FNATg), and FNATg/SerumTg measurement. Lymph node pathological results after surgery were taken as the gold standard. Using Mann-Whitney U test, Pearson linear model and ROC curve were used for data analysis. Results: The sensitivity, specificity and accuracy of FNATg for the diagnosis of lateral neck lymph node metastasis were respectively 93.7%, 90.0% and 93.3% and those of FNATg/SerumTg were respectively 89.9%, 90.0% and 93.2% respectively, the threshold values for FNATg and FNATg/SerumTg were 0.925 ng/ml and 1.007, respectively. The sensitivity, specificity and accuracy of FNATg combined with FNAC were respectively 91.0%,93.5% and 94.4%. The existence of thyroid tissue and the expression of serum Tg did not affect the expression of lymph node FNATg. The FNATg cutoff value of 0.925 ng/ml showed the best diagnostic performance in patients with a thyroid gland, while the FNATg/SerumTg cutoff ratio of 14.95 showed the best diagnostic performance in patients without a thyroid gland. The serum TgAb significantly interfered with the expression of FNATg in the lateral neck metastatic lymph nodes (P=0.049). Conclusions: FNATg alone or the combination of FNATg with FNAC are highly reliable in the diagnosis of lateral neck lymph node metastases in patients with PTC. The expression of TgAb may interfere with the accuracy of the diagnostic performance of FNATg.


Assuntos
Biópsia por Agulha Fina , Linfonodos/patologia , Câncer Papilífero da Tireoide/patologia , Câncer Papilífero da Tireoide/secundário , Neoplasias da Glândula Tireoide/patologia , Humanos , Metástase Linfática , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Tireoglobulina/análise , Câncer Papilífero da Tireoide/química , Neoplasias da Glândula Tireoide/química
9.
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 54(10): 764-768, 2019 Oct 07.
Artigo em Zh | MEDLINE | ID: mdl-31606990

RESUMO

Objective: To study the diagnostic value of a multi-gene molecular testing in cytologically indeterminate thyroid nodules. Methods: From February 2018 to September 2018, patients with thyroid nodules who underwent fine needle aspiration(FNA) at Peking University Cancer Hospital were enrolled. Three hundred and sixty patients were included, consisting of 86 men and 274 women, with a mean age of 45.8 years (between 13 and 89 years old). Among 391 nodules, 141 were cytologically inderminate and 75 were resected. FNA samples underwent prospective testing using a next-generation sequencing (NGS) assay, which included 16 genes for point mutations and 26 types of gene fusions. The testing results of indeterminate nodules were compared with surgical outcomes, to determine the diagnostic performance. The results were compared with the BRAF V600E single gene mutation analysis by χ(2) test. Results: The multi-gene testing showed a sensitivity of 73.2%, specificity of 96.8%, positive predictive value of 96.8%, and negative predictive value of 73.2%. The diagnostic accuracy of multi-gene testing was significantly higher than the BRAF V600E mutation test (83.3% vs 73.6%, χ(2)=31.588, P<0.01). Conclusion: Multi-gene testing in FNA samples is an effective method to diagnose cytologically indeterminate thyroid nodules, which has a higher accuracy than BRAF V600E mutation detection.


Assuntos
Biópsia por Agulha Fina , Testes Genéticos , Nódulo da Glândula Tireoide/genética , Nódulo da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Prospectivos , Proteínas Proto-Oncogênicas B-raf/genética , Análise de Sequência , Nódulo da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/cirurgia , Adulto Jovem
10.
Artigo em Zh | MEDLINE | ID: mdl-30813697

RESUMO

Objective:To further recognize the clinical characteristics of non-syndromic enlarged vestibular aqueduct through the retrospective analysis of cases, with the purpose of providing references for clinical diagnosis and treatment. Method:Collect 54 cases of non-syndromic enlarged vestibular aqueduct, and analyze their clinical characteristics after history taking, physical examination, audiometry and imaging examination. Measure the biggest width of midpoint between internal and external of vestibular aqueduct on temporal bone thin-section CT, and analyze the relationship between the pipe width and sides of ear, types of hearing loss and degree of hearing loss through t test. Result:All 54 patients with non-syndromic enlarged vestibular aqueduct had bilateral ear involvement. There were 42 cases with prelingual deafness, 12 cases with postlingual deafness, and there were 38 ears with severe deafness, 70 ears with profound deafness. Ninety-six ears of hearing loss showed sensorineural deafness, and 12 ears manifested mixed deafness. The biggest width of midpoint between internal and external of vestibular aqueduct spread over 1.60-3.90 mm, and the average was 2.60 mm. There were no significant differences in data between left and right sides, degree of hearing loss and type of hearing loss. Conclusion:Non-syndromic enlarged vestibular aqueduct mainly manifests serious sensorineural deafness, and the diagnosis depends on imaging examination. There is no difference in the degree of expanding between left and right ear, and the extent of enlargement is not related to the type and the severity of hearing loss.


Assuntos
Perda Auditiva Neurossensorial , Aqueduto Vestibular/anormalidades , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Neurossensorial/diagnóstico , Humanos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
11.
Eur Rev Med Pharmacol Sci ; 20(11): 2324-37, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27338058

RESUMO

OBJECTIVE: The aim of this study was to explore the association of polymorphisms in DLG5 gene (G113A, C4136A and e26) with inflammatory bowel disease (IBD) risk. MATERIALS AND METHODS: A total of 25 studies involved 26583 subjects were pooled for analysis. The odds ratios (ORs) and 95% confidence intervals (95% CIs) were used to pool the effect size. RESULTS: For G113A variant, a significant association was observed with CD risk in children (A vs. G: OR = 0.745, 95% CI = 0.569-0.977) and high quality studies (A vs. G: OR = 0.913, 95% CI = 0.850-0.981). Additionally, the results of genotype-phenotype analysis suggested G113A variant was associated with colonic involvement in CD. However, in overall population, the results indicated G113A variant was not associated with CD or UC. We also provided evidence that C4136A polymorphism had different effects on CD risk between Europeans (AA vs. CC: OR = 3.239, 95% CI = 1.149-9.136) and Asians (AA vs. CC: OR = 0.511, 95% CI = 0.299-0.873). For UC, patients with AA genotype of C4136A variant had a significantly increased UC risk (AA vs. CC: OR = 3.877, 95% CI = 1.168-12.867). Finally, no association was detected with G113A or e26 polymorphism in CD or UC patients. CONCLUSIONS: This meta-analysis indicated G113A variant may be significantly associated with CD risk in children and colonic involvement.


Assuntos
Colite Ulcerativa/genética , Doença de Crohn/genética , Doenças Inflamatórias Intestinais/genética , Proteínas de Membrana/genética , Proteínas Supressoras de Tumor/genética , Criança , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Doenças Inflamatórias Intestinais/epidemiologia , Masculino , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único
13.
J Korean Med Sci ; 3(2): 83-8, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3267359

RESUMO

Several months after left radical mastectomy without irradiation therapy for breast cancer, a 74-year-old woman developed severe edema on the homolateral arm extending to the axilla. Ten years later, purplish to brownish blotch and nodules accompanied with heating sensation and pain appeared and increased in size gradually on the left forearm. The patient was treated by irradiation therapy under the clinical and histopathologic diagnosis of Stewart-Treves syndrome and almost all of the skin lesions and symptoms disappeared after irradiation of 6450 rads.


Assuntos
Neoplasias da Mama/cirurgia , Hemangiossarcoma/etiologia , Linfedema/complicações , Mastectomia Radical/efeitos adversos , Neoplasias Cutâneas/etiologia , Idoso , Braço , Feminino , Hemangiossarcoma/patologia , Hemangiossarcoma/radioterapia , Humanos , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/radioterapia
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