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1.
Zhonghua Wai Ke Za Zhi ; 62(5): 379-386, 2024 May 01.
Artigo em Zh | MEDLINE | ID: mdl-38548605

RESUMO

Objective: To investigate the risk factors and prognostic value of the textbook outcome (TO) in patients with advanced gastric cancer (AGC) who underwent neoadjuvant chemotherapy followed by surgical resection. Methods: This is a retrospective cohort study. A total of 253 patients with AGC who underwent neoadjuvant chemotherapy combined with gastrectomy and D2 lymphadenectomy in the Department of Gastric Surgery, Fujian Medical University Union Hospital from January 2010 to December 2019 were retrospectively included. There were 195 males and 58 females, aged (60.3±10.0) years (range: 27 to 75 years). The patients were then divided into the TO group (n=168) and the non-TO group (n=85). Multivariate Logistic regression was used to analyze the independent predictors of TO. Univariate and multivariate Cox analysis were used to analyze independent prognosis factors for overall survival (OS) and disease-free survival (DFS). Propensity score matching was performed to balance the TO and non-TO groups, and the Kaplan-Meier method was used to calculate survival rates and draw survival curves. Results: Among the 253 patients, 168 patients (66.4%) achieved TO. The Eastern Cooperative Oncology Group score (OR=0.488, 95%CI: 0.278 to 0.856, P=0.012) and ypN stage (OR=0.626, 95%CI:0.488 to 0.805, P<0.01) were independently predictive of TO. Multivariate analysis revealed that TO was an independent risk factor for both OS (HR=0.662, 95%CI: 0.457 to 0.959,P=0.029) and DFS (HR=0.687, 95%CI: 0.483 to 0.976, P=0.036). After matching, the 5-year OS rate (42.2% vs. 27.8%) and the 5-year DFS rate (37.5% vs. 27.8%) were significantly higher in the TO group than in the non-TO group (both P<0.05). Furthermore, patients in the non-TO group benefited significantly from postoperative chemotherapy (both P<0.05), but those in the TO group did not (both P>0.05). Conclusion: TO is an independent prognosis factor in patients undergoing neoadjuvant chemotherapy and surgery for AGC and is associated with postoperative chemotherapy benefits.


Assuntos
Gastrectomia , Terapia Neoadjuvante , Neoplasias Gástricas , Humanos , Masculino , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/terapia , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Prognóstico , Idoso , Adulto , Taxa de Sobrevida , Excisão de Linfonodo , Intervalo Livre de Doença , Fatores de Risco , Resultado do Tratamento , Quimioterapia Adjuvante , Pontuação de Propensão , Estimativa de Kaplan-Meier , Modelos de Riscos Proporcionais
2.
Bull Math Biol ; 85(6): 54, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37166513

RESUMO

Metapopulation models have been a popular tool for the study of epidemic spread over a network of highly populated nodes (cities, provinces, countries) and have been extensively used in the context of the ongoing COVID-19 pandemic. In the present work, we revisit such a model, bearing a particular case example in mind, namely that of the region of Andalusia in Spain during the period of the summer-fall of 2020 (i.e., between the first and second pandemic waves). Our aim is to consider the possibility of incorporation of mobility across the province nodes focusing on mobile-phone time-dependent data, but also discussing the comparison for our case example with a gravity model, as well as with the dynamics in the absence of mobility. Our main finding is that mobility is key toward a quantitative understanding of the emergence of the second wave of the pandemic and that the most accurate way to capture it involves dynamic (rather than static) inclusion of time-dependent mobility matrices based on cell-phone data. Alternatives bearing no mobility are unable to capture the trends revealed by the data in the context of the metapopulation model considered herein.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , Modelos Biológicos , Conceitos Matemáticos , Tempo
3.
Br J Cancer ; 127(5): 872-878, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35676320

RESUMO

BACKGROUND: Efficacy of vitamin D supplementation may vary by dosing strategies and adiposity. To address such heterogeneity, we performed a meta-analysis of randomised controlled trials of vitamin D supplementation and total cancer outcomes. METHODS: PubMed and Embase were searched through January 2022. Summary relative risk (SRR) and 95% confidence interval (CI) were estimated using the DerSimonian-Laird random-effects model. RESULTS: For total cancer incidence (12 trials), the SRR for vitamin D supplementation vs. control group was 0.99 (95% CI, 0.94-1.03; P = 0.54; I2 = 0%). No significant association was observed regardless of whether the supplement was given daily or infrequently in a large-bolus. Yet, among trials testing daily supplementation, a significant inverse association was observed among normal-weight individuals (SRR, 0.76; 95% CI, 0.64-0.90; P = 0.001, I2 = 0%), but not among overweight or obese individuals (Pheterogeneity = 0.02). For total cancer mortality (six trials), the SRR was 0.92 (95% CI, 0.82-1.03; P = 0.17; I2 = 33%). A significant inverse association emerged (SRR, 0.87; 95% CI, 0.78-0.96; P = 0.007; I2 = 0%) among studies testing daily supplementations but not among studies that testing infrequent large-bolus supplementations (Pheterogeneity = 0.09). CONCLUSIONS: For vitamin D supplementation, daily dosing, but not infrequent large-bolus dosing, reduced total cancer mortality. For total cancer incidence, bolus dosing did not reduce the risk and the benefits of daily dosing were limited to normal-weight individuals.


Assuntos
Neoplasias , Vitamina D , Suplementos Nutricionais , Humanos , Incidência , Neoplasias/tratamento farmacológico , Neoplasias/epidemiologia , Obesidade
4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(7): 926-931, 2022 Jul 06.
Artigo em Zh | MEDLINE | ID: mdl-35899344

RESUMO

Objective: To explore the association of DNA methylation with immune response to hepatitis B (HepB) vaccine in Han nationality children from Guangxi province. Methods: A total of 263 children aged 8-9 months who had completed HepB immunization program were recruited from three hospitals in Guangxi province by using unmatched case-control method. Children with the HepB surface antibody concentration(Anti-HBs)<100 mIU/ml was set as the case group and ≥100 mIU/ml as the control group. Multiplex PCR and heavy sulfite sequencing were used to treat the samples. Illumina platform was used for high-throughput DNA methylation sequencing of IFNG gene target regions and CpG sites. Unconditional logistic regression was used to analyze the association between cytosine-phospho-guanosine DNA methylation at 18 loci of IFNG gene and HepB immune response level. Results: There were 104 children in the case group and 159 in the control group. The median (Q1, Q3) level of anti-HBs in two groups were 62.34 (30.06, 98.88) mIU/ml and 1 089.10 (710.35, 1 233.45) mIU/ml. The methylation levels of IFNG_1 gene 44 and 93 locus in the case group were higher than those in the control group (P<0.05). The unconditional logistic regression model showed that the DNA methylation level of IFNG_1 gene at 44 (OR=1.18, 95%CI: 1.03-1.35) and 93 (OR=1.21, 95%CI: 1.07-1.38) locus was associated with the HepB response level. Conclusion: The changes of DNA methylation at locus 44 and 93 of IFNG_1 gene may be relevant factors affecting the response level of HepB in Han nationality children from Guangxi province.


Assuntos
Vacinas contra Hepatite B , Hepatite B , Criança , China , Metilação de DNA , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Humanos , Imunização Secundária , Interferon gama
5.
Bull Exp Biol Med ; 173(3): 335-340, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35854020

RESUMO

This study aimed to explore the effects of Wenyang Zhenshuai granules (WZG) on the morphology of cardiomyocytes, cell viability, and the expression of key mitochondrial autophagy proteins in the doxorubicin-induced model of H9c2 cardiomyocyte injury. Cardiomyocytes were cultured for 44 h and divided into 4 groups: intact control, doxorubicin-injured cells (DOX), doxorubicin-injured cells treated with WZG (DOX+WZG), and doxorubicin-injured cells treated with valsartan (DOX+valsartan; reference group). The morphology of cardiomyocytes was analyzed under an inverted microscope; cardiomyocyte survival rate was determined by MTT assay. The expression of the key mitochondrial autophagy proteins (PINK1, parkin, LC3-II, and prohibitin-2) was analyzed by Western blotting. WZG down-regulated the expression of the key mitochondrial autophagy proteins in DOX-injured cells, which may be one of the important mechanisms for regulating ventricular remodeling and cardiomyocyte apoptosis.


Assuntos
Proteínas Mitocondriais , Miócitos Cardíacos , Apoptose , Autofagia , Doxorrubicina/farmacologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/metabolismo , Valsartana/metabolismo , Valsartana/farmacologia
6.
Zhonghua Wai Ke Za Zhi ; 60(5): 479-486, 2022 May 01.
Artigo em Zh | MEDLINE | ID: mdl-35359091

RESUMO

Objectives: To analyze the current development status of gastric cancer (GC) randomized controlled trials (RCT) between 2000 and 2019, and to review the basic characteristics of published RCT. Methods: ClinicalTrials.gov was searched for phase 3 or 4 RCT conducted between January 2000 and December 2019 with the keyword "gastric cancer", and the development trend of different types of RCT during different time periods was described. Basic features of registered RCT such as intervention, study area, single-center or multicenter, sample size, and funding were presented. PubMed and Scopus databases were searched to judge the publication status of studies completed until June 2016. The adequacy of the report was estimated by the Consolidated Standards of Reporting Trials (CONSORT) checklist. Design flaws were evaluated by Cochrane tool and/or whether a systematic literature review was cited. The data was analyzed by χ2 test or Fisher exact test. Results: There were 262 RCT including in the present study. The number of GC-RCT registered on ClinicalTrials.gov had been on the rise from 1 case in 2000 to 30 cases in 2015. The proportion of RCT associated with targeted therapy or immunotherapy increased from 0 during 2000-2004 to 37.1% (36/97) during2015-2019. The RCT registered in Asia was 191 cases, while that in non-Asia region was 71 cases. The proportion of multi-center RCT from non-Asia was higher than that from Asia (70.4% (50/71) vs. 50.3% (96/191), χ²=8.527, P=0.003). The proportion of RCT published was 59.1% (81/137). Among the published RCT, 65 (80.2%) studies were reported adequately, but 63 (77.8%) studies had avoidable design limitations. Conclusions: Targeted therapy and immunotherapy have become research hotspots in the treatment of GC. At present, there are inadequate multicenter RCT in Asia, and the publication rate of RCT is low. A considerable number of published RCT are reported inadequately and have avoidable design flaws.

7.
Zhonghua Wai Ke Za Zhi ; 60(5): 478-485, 2022 May 01.
Artigo em Zh | MEDLINE | ID: mdl-35417942

RESUMO

Objectives: To analyze the current development status of gastric cancer (GC) randomized controlled trials (RCT) between 2000 and 2019, and to review the basic characteristics of published RCT. Methods: ClinicalTrials.gov was searched for phase 3 or 4 RCT conducted between January 2000 and December 2019 with the keyword "gastric cancer", and the development trend of different types of RCT during different time periods was described. Basic features of registered RCT such as intervention, study area, single-center or multicenter, sample size, and funding were presented. PubMed and Scopus databases were searched to judge the publication status of studies completed until June 2016. The adequacy of the report was estimated by the Consolidated Standards of Reporting Trials (CONSORT) checklist. Design flaws were evaluated by Cochrane tool and/or whether a systematic literature review was cited. The data was analyzed by χ2 test or Fisher exact test. Results: There were 262 RCT including in the present study. The number of GC-RCT registered on ClinicalTrials.gov had been on the rise from 1 case in 2000 to 30 cases in 2015. The proportion of RCT associated with targeted therapy or immunotherapy increased from 0 during 2000-2004 to 37.1% (36/97) during 2015-2019. The RCT registered in Asia was 191 cases, while that in non-Asia region was 71 cases. The proportion of multi-center RCT from non-Asia was higher than that from Asia (70.4% (50/71) vs. 50.3% (96/191), χ²=8.527, P=0.003). The proportion of RCT published was 59.1% (81/137). Among the published RCT, 65 (80.2%) studies were reported adequately, but 63 (77.8%) studies had avoidable design limitations. Conclusions: Targeted therapy and immunotherapy have become research hotspots in the treatment of GC. At present, there are inadequate multicenter RCT in Asia, and the publication rate of RCT is low. A considerable number of published RCT are reported inadequately and have avoidable design flaws.


Assuntos
Neoplasias Gástricas , Humanos , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Gástricas/terapia
8.
Zhonghua Wai Ke Za Zhi ; 60(9): 853-859, 2022 Sep 01.
Artigo em Zh | MEDLINE | ID: mdl-36058712

RESUMO

Objective: To examine the long term outcome of splenic hilar lymphadenectomy (SHL) for locally advanced Siewert type Ⅱ and Ⅲ adenocarcinoma of esophagogastric junction (AEG) with a tumor diameter ≥4 cm. Methods: A total of 489 locally advanced Siewert type Ⅱ and Ⅲ AEG patients with a tumor diameter ≥4 cm who underwent radical resection from January 2010 to April 2016 were included. There were 383 males and 106 females. There were 225 patients aged≥65 years and 264 patients aged <65 years. SHL was conducted in 270 patients(SHL group). Wilcoxon rank-sum test or χ2 test were conducted for inter-group comparison. Cox proportional hazard regression was used to analyze the long term outcome of SHL and the prognosis factors of overall survival. Kaplan-Meier curve was drawn finally. The results of survival analysis were verified by Log-rank test. Results: Followed-up to April 2021,the median follow-up time was 78.0 months (range: 74.0 to 85.0 months), the follow-up rate was 95.5%(467/489). The splenic hilar lymphnode metastasis rate of the SHL group was 12.6% (34/270). Younger patients (<65 years old), less complications, higher proportion of patients received adjuvant chemotherapy were demonstrated in the SHL group (χ2: 5.644 to 6.744, all P<0.05). Multivariate analysis showed that SHL was the independent prognosis factor of overall survival for patients with Siewert type Ⅱ and Ⅲ AEG and a tumor diameter≥4 cm (HR=0.68, 95%CI: 0.52 to 0.88, P=0.004) along with preoperative CA19-9, pathological T stage, pathological N stage, adjuvant chemotherapy and postoperative complication. Further subgroup analysis demonstrated that the SHL group had better 5-year overall survival than non-SHL group (62.4% vs. 39.2%, χ2=17.983, P=0.006) in Siewert type Ⅲ AEG rather than in Siewert type Ⅱ AEG(57.3% vs. 53.7%, χ2=3.031, P=0.805). Conclusion: In experienced center, splenic hilar lymphadenectomy can improve the prognosis of Siewert type Ⅲ AEG with a tumor diameter ≥4 cm.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Neoplasias Esofágicas , Junção Esofagogástrica/cirurgia , Feminino , Humanos , Excisão de Linfonodo/métodos , Metástase Linfática/patologia , Masculino , Estudos Retrospectivos , Neoplasias Gástricas/cirurgia , Análise de Sobrevida
9.
Nanotechnology ; 32(40)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34171853

RESUMO

Traditional optical switches relying on the weak, volatile thermo-optic or electro-optic effects of Si or SiN waveguides show a high consumption and large footprint. In this paper, we reported an electric-driven phase change optical switch consisting of a Si waveguide, Ge2Sb2Te5(GST) thin film and graphene heater suitable for large-scale integration and high-speed switching. The reversible transition between the amorphous and crystalline states was achieved by applying two different voltage pulses of 1.4 V (SET) and 4 V (RESET). The optical performance of the proposed switch showed a high extinction ration of 44-46 dB in a wide spectral range (1525-1575 nm), an effective index variation of Δneff = 0.49 and a mode loss variation of Δα = 15 dBµm-1at the wavelength of 1550 nm. In thermal simulations, thanks to the ultra-high thermal conductivity of graphene, the proposed switch showed that the consumption for the SET process was only 3.528 pJ with a 1.4 V pulse of 5 ns, while a 4 V pulse of 1.5 ns was needed for RESET process with a consumption of 1.05 nJ. Our work is helpful to analyze the thermal-conduction phase transition process of on-chip phase change optical switches, and the design of the low-energy-consumption switch is conducive to the integrated application of photonic chips.

10.
Nanotechnology ; 31(45): 455206, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-32707570

RESUMO

On-chip photonics devices relying on the weak, volatile thermo-optic or electro-optic effects of silicon usually suffer from high insertion loss (IL) and a low refractive index coefficient. In this paper, we designed two novel 1 × 1 and 1 × 2 phase-change optical switches based on a signal-mode Si waveguide integrated with a Ge2Sb2Te5 (GST) top clad layer, respectively. The three-state switch including amorphous GST (a-GST), face centered cubic crystalline phase (FCC-GST) and hexagonal crystalline phase (HCP-GST) operated by utilizing the dramatic difference in the optical constants between the amorphous and two crystalline phases of GST. In the case of the 1 × 1 optical switch, an extinction ratio (ER) of 8.9 dB and an extremely low IL of 0.8 dB were achieved using an optimum GST length of only 2 µm. While for the 1 × 2 optical switch, low ILs in the range of 0.15 ∼ 0.35 dB for both 'cross' (a-GST) and 'bar' (FCC-GST and HCP-GST) states were also obtained. Additionally, we found that both ILs and mode losses of the switch with HCP-GST were about half lower than those with FCC-GST, which means FCC-GST could be instituted by HCP-GST in the traditional ovonic switch with the consideration of low loss. This research provides the fundamental understanding for the realization of low loss and non-volatile Si-GST hybrid optical switches, with potential for future communication networks.

11.
Zhonghua Zhong Liu Za Zhi ; 42(12): 1056-1062, 2020 Dec 23.
Artigo em Zh | MEDLINE | ID: mdl-33342165

RESUMO

Objective: To analyze the safety and efficacy of percutaneous vertebroplasty combined with interstitial implantation (125)I of seeds (PVPI) in the treatment of thoracic vertebroplasty with posterior vertebra defect. Methods: A retrospective analysis of the clinical data of 64 patients with thoracic spine metastases admitted to Yunnan Cancer Hospital from November 2017 to May 2019 was conducted, including 32 patients with posterior vertebra defect (experimental group) and 32 cases without (control group). Forty-two vertebral bodies of 32 patients in the experimental group were treated with improved PVPI surgery, which performed with the secondary sealing method and inclined puncture needle injection bone cement rotary filling technology, to reduce leakage. The 54 vertebral bodies of 32 patients in control group underwent PVPI. The two groups of patients were followed up on the second day, one month, three months and six months after the operation, and the short-term efficacy, long-term efficacy and safety indicators of the two groups were compared. Results: All 64 patients successfully completed the surgical treatment. The visual analogue scores and Karnofsky scores of the experimental group and the control group were improved to varying degrees on the second day, 1 month, 3 months and 6 months after the operation. There was no statistically significant difference between the two groups (P>0.05). The amount of bone cement in the experimental group and control group was (2.36±0.20) ml and (2.39±0.17) ml, and the difference was not statistically significant (P=0.482). The amount of (125)I seed implantation was (30.63±0.91) and (32.56±0.68), respectively, the difference was not statistically significant (P=0.925). The partial response rates of the study group and the control group were 81.3% and 87.5%, the stable disease rates were 12.5% and 9.4%, the differences were not statistically significant (P>0.05). The median overall survival (mOS) of the study group was 13 months, and the median progression-free survival (mPFS) was 8 months. The mOS of the control group was 14 months, and the mPFS was 8 months. The differences were not statistically significant (P>0.05). In the experimental group, 6 (14.3%) vertebral bodies had cement leakage, of which 2 (4.8%) were cement leakage at posterior vertebra, 4 (9.5%) were paravertebral cement leakage. Seven (13.0%) paravertebral cement leakage occurred in the control group. There was no significant difference in bone cement leakage between the two groups (P=0.097). Bone cement leakage in both groups did not cause serious complications such as spinal cord injury and paraplegia. Conclusion: The application of PVPI in the treatment of thoracic metastatic tumor patients with posterior vertebra defect can acquire better clinical efficacy and safety through conduction of the improved intraoperative technology and paying more attention to the control of bone cement distribution and other issues.


Assuntos
Radioisótopos do Iodo , Neoplasias Torácicas , Vértebras Torácicas , Vertebroplastia , China , Humanos , Radioisótopos do Iodo/uso terapêutico , Metástase Neoplásica , Estudos Retrospectivos , Neoplasias Torácicas/patologia , Neoplasias Torácicas/terapia , Vértebras Torácicas/patologia , Resultado do Tratamento , Vertebroplastia/efeitos adversos , Vertebroplastia/métodos
12.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(11): 1275-1282, 2020 Nov 06.
Artigo em Zh | MEDLINE | ID: mdl-33147929

RESUMO

Objective: To reveal the relationship between G6PD genotypes and the G6PD enzyme activities in dried blood spots of newborn screening. Methods: Simple random sampling procedure was used in this study. The fluorescence PCR melting curve analysis was performed to classify G6PD gene variants in 635 neonates coming from Guangzhou Newborn Screening Center during October 1 to 20, 2016, including 15 reported variants. Those samples consisted of 377 cases with screening positive results (261 from males and 116 from females) and 258 cases with screening negative results (32 from males and 226 from females). The cut-off value of G6PD was less than 2.6 U/g Hb in dry blood spots. Sanger sequencing for G6PD gene was used in 7 cases with screening negative results under simple random sampling. One-way ANOVA and least significant difference method (LSD) test were performed to compare the difference of G6PD activity among genotypes. Results: The top 6 frequency of G6PD gene variants were c.1388G>A(35.07%), c.1376G>T(32.13%), c.95A>G(12.72%), c.871G>A(8.32%), c.1024C>T(4.08%) and c.392G>T(2.28%), accounting for 94.62% of all variant alleles (580/613). A total of 253 males positive for enzyme activity were detected to have gene mutations. The positive rate of G6PD enzyme activity was 98.06%(253/258). The mean values of G6PD activities for c.1376G>T,c.95A>G and c.1388G>A were 0.85, 1.10 and 1.28 U/g Hb, respectively. There were significant differences among the three groups (F=28.7, P<0.01). A total of 105 females positive for enzyme activity were detected to have gene mutations. The positive rate of G6PD enzyme activity was 90.52%(105/116). The positive rate of G6PD enzyme activity was 26.95% among 256 females with one point mutation while it was 83.72% in females with multi-allele variants. The G6PD activity of heterozygous females was (2.9±0.8) U/g Hb, which was significant higher than that of females with multi-allele variants (1.5±1.0) U/g Hb (t=8.6,P<0.01). Conclusions: G6PD activities in dried blood spots were related to G6PD genotypes in males. They were also associated with the numbers of allele variants in females. Newborn screening for G6PD deficiency can be used to detect most of G6PD-deficient hemizygotes and female patients with multi-allele variants, which is helpful for preventing neonatal jaundice and medicine application.


Assuntos
Deficiência de Glucosefosfato Desidrogenase , Glucosefosfato Desidrogenase , Feminino , Genótipo , Glucosefosfato Desidrogenase/genética , Deficiência de Glucosefosfato Desidrogenase/genética , Heterozigoto , Humanos , Recém-Nascido , Masculino , Mutação , Triagem Neonatal
13.
Phys Rev Lett ; 123(10): 106402, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31573295

RESUMO

In heavy-fermion compounds, the dual character of f electrons underlies their rich and often exotic properties like fragile heavy quasiparticles, a variety of magnetic orders and unconventional superconductivity. 5f-electron actinide materials provide a rich setting to elucidate the larger and outstanding issue of the competition between magnetic order and Kondo entanglement and, more generally, the interplay among different channels of interactions in correlated electron systems. Here, by using angle-resolved photoemission spectroscopy, we present the detailed electronic structure of USb_{2} and observe two different kinds of nearly flat bands in the antiferromagnetic state of USb_{2}. Polarization-dependent measurements show that these electronic states are derived from 5f orbitals with different characters; in addition, further temperature-dependent measurements reveal that one of them is driven by the Kondo correlations between the 5f electrons and conduction electrons, while the other reflects the dominant role of the magnetic order. Our results on the low-energy electronic excitations of USb_{2} implicate orbital selectivity as an important new ingredient for the competition between Kondo correlations and magnetic order and, by extension, in the rich landscape of quantum phases for strongly correlated f electron systems.

14.
Zhonghua Yi Xue Za Zhi ; 99(11): 812-817, 2019 Mar 19.
Artigo em Zh | MEDLINE | ID: mdl-30893722

RESUMO

Objectives: The aim of the study was to determine whether there was gender difference in clinical manifestations and comorbidities in the patients with Spondyloarthritis (SpA) in China. Methods: 346 patients fulfilling ASAS criteria for SpA were recruited from the Third Affiliated Hospital of Sun Yat-sen University, including 280 males and 66 females. A comparison was conducted in terms of age at onset, disease course, family history, HLA-B27 positivity, clinical manifestations, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP), the bath ankylosing spondylitis disease activity index (BASDAI) and AS disease activity score (ASDAS), and comorbidities between male and female patients. Results: Compared with female patients, male patients were younger at disease onset (22±7 vs 27±9, P<0.001),had higher rates of morning stiffness (74.3%), and higher scores of CRP and ASDAS-CRP (P<0.010, P=0.014). However, no significant gender difference was observed in other clinical parameters like clinical manifestations, family history, HLA-B27 positivity, BASDAI, and BASFI and treatment. Male SpA patients had a higher prevalence of Hepatitis B virus (HBV) infection (26.2%) than that of female patients (8.3%), and a higher prevalence of osteoporosis (30.5% vs 14.3%,P<0.01), especially with a lower lumbar T score. Logistic regression analysis reviewed that limited weight (OR=0.94, P<0.001), high ASDAS-CRP (OR=1.58, P=0.006) and male (OR=8.02, P=0.004) are more inclined to have osteoporosis. Conclusion: Compared with female patients, male patients were younger at disease onset and higher scores of CRP and ASDAS-CRP. No significant gender difference was observed in clinical manifestations, family history, HLA-B27 positivity, BASDAI, and BASFI and treatment. Male SpA patients had a higher prevalence of HBV infection and osteoporosis than female patients. Comorbidities should be paid more attention in the patients with SpA.


Assuntos
Espondilartrite , Sedimentação Sanguínea , China , Feminino , Humanos , Masculino , Índice de Gravidade de Doença
15.
Phys Rev Lett ; 120(10): 106401, 2018 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-29570327

RESUMO

van der Waals heterostructures (VDWHs) exhibit rich properties and thus has potential for applications, and charge transfer between different layers in a heterostructure often dominates its properties and device performance. It is thus critical to reveal and understand the charge transfer effects in VDWHs, for which electronic structure measurements have proven to be effective. Using angle-resolved photoemission spectroscopy, we studied the electronic structures of (PbSe)_{1.16}(TiSe_{2})_{m} (m=1, 2), which are naturally occurring VDWHs, and discovered several striking charge transfer effects. When the thickness of the TiSe_{2} layers is halved from m=2 to m=1, the amount of charge transferred increases unexpectedly by more than 250%. This is accompanied by a dramatic drop in the electron-phonon interaction strength far beyond the prediction by first-principles calculations and, consequently, superconductivity only exists in the m=2 compound with strong electron-phonon interaction, albeit with lower carrier density. Furthermore, we found that the amount of charge transferred in both compounds is nearly halved when warmed from below 10 K to room temperature, due to the different thermal expansion coefficients of the constituent layers of these misfit compounds. These unprecedentedly large charge transfer effects might widely exist in VDWHs composed of metal-semiconductor contacts; thus, our results provide important insights for further understanding and applications of VDWHs.

16.
Phys Rev Lett ; 121(11): 117002, 2018 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-30265111

RESUMO

The mechanism of high superconducting transition temperatures (T_{c}) in bismuthates remains under debate despite more than 30 years of extensive research. Our angle-resolved photoemission spectroscopy studies on Ba_{0.51}K_{0.49}BiO_{3} reveal an unexpectedly 34% larger bandwidth than in conventional density functional theory calculations. This can be reproduced by calculations that fully account for long-range Coulomb interactions-the first direct demonstration of bandwidth expansion due to the Fock exchange term, a long-accepted and yet uncorroborated fundamental effect in many body physics.Furthermore, we observe an isotropic superconducting gap with 2Δ_{0}/k_{B}T_{c}=3.51±0.05, and strong electron-phonon interactions with a coupling constant λ∼1.3±0.2. These findings solve a long-standing mystery-Ba_{0.51}K_{0.49}BiO_{3} is an extraordinary Bardeen-Cooper-Schrieffer superconductor, where long-range Coulomb interactions expand the bandwidth, enhance electron-phonon coupling, and generate the high T_{c}. Such effects will also be critical for finding new superconductors.

17.
Phys Rev Lett ; 120(6): 066403, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29481263

RESUMO

A key issue in heavy fermion research is how subtle changes in the hybridization between the 4f (5f) and conduction electrons can result in fundamentally different ground states. CeRhIn_{5} stands out as a particularly notable example: when replacing Rh with either Co or Ir, antiferromagnetism gives way to superconductivity. In this photoemission study of CeRhIn_{5}, we demonstrate that the use of resonant angle-resolved photoemission spectroscopy with polarized light allows us to extract detailed information on the 4f crystal field states and details on the 4f and conduction electron hybridization, which together determine the ground state. We directly observe weakly dispersive Kondo resonances of f electrons and identify two of the three Ce 4f_{5/2}^{1} crystal-electric-field levels and band-dependent hybridization, which signals that the hybridization occurs primarily between the Ce 4f states in the CeIn_{3} layer and two more three-dimensional bands composed of the Rh 4d and In 5p orbitals in the RhIn_{2} layer. Our results allow us to connect the properties observed at elevated temperatures with the unusual low-temperature properties of this enigmatic heavy fermion compound.

18.
J Biol Regul Homeost Agents ; 32(2): 371-377, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29685021

RESUMO

The aim of this study is to investigate the main category of hand-foot-mouth (HFM) virus and analyze the distribution characteristics and susceptible population of HFM disease in China. Infants who have had HFM disease for less than 7 days were selected from the First Affiliated Hospital of Guangxi Medical University, Guangxi, China. Various specimens were collected from the infants, and EV71 and CA16 nucleic acid detections were performed using fluorescence quantitative assay. The positive results of the specimens were compared to determine the components of the pathogen. Moreover, the data of the target cases were analyzed based on Geographic Information System (GIS) to obtain the spatial-temporal epidemiological features of HFM disease in China. The detection rate of HFM virus in the throat swab, feces, bleb fluid and cerebrospinal fluid were 75%, 81.13%, 85.71% and 25%, respectively, indicating that the detection rate of virus in the bleb fluid was the highest. When the detection was based on more than one specimen, it was found that the positive rate was higher compared to detection based on a single specimen. The positive detection rate of EV71 in the target specimens was significantly higher than that of CA16 and mixed infection. Moreover, CA16 infection was usually accompanied by EV71 infection. As to spatial-temporal distribution, hand-foot-month disease broke out in the South of China in April, then spread to the north, and diminished in July. There was a notable difference in the number of cases between different provinces. EV71 and CA16 are the main viruses inducing HFM disease, especially EV71. Fluorescence quantitative polymerase chain reaction with high sensitivity can be used to detect the copy number of viruses, which is applicable to the early diagnosis of HFM disease. The incidence of HFM disease is notably different according to the influence of time, geographical space, gender and the living conditions of the children. Early diagnosis and treatment based on scientific methods are needed to reduce the incidence of severe diseases and avoid death.


Assuntos
Sistemas de Informação Geográfica , Doença de Mão, Pé e Boca/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Feminino , Doença de Mão, Pé e Boca/virologia , Humanos , Lactente , Masculino
19.
Zhonghua Yi Xue Za Zhi ; 98(31): 2466-2470, 2018 Aug 21.
Artigo em Zh | MEDLINE | ID: mdl-30138996

RESUMO

Objective: To explore the changes of cerebral white matter in the hyperacute period (<24 h) patients with mild traumatic brain injury (mTBI) by diffusion kurtosis imaging(DKI) technique. Methods: A total of 52 patients with mTBI were included in this study, collected in Emergency Department of Affiliated Hospital of Hangzhou Normal University from May 2016 to June 2017. Twenty-one healthy controls were recruited at the mean time(gender, age and years of education were matched with the patients). DKI data were acquired with 3.0 T scanners.The FSL software was used to preprocess the DKI data, and the white matter abnormalities were detected by tract-based spatial statistics (TBSS). Results: There were no statistical differences in gender, age and years of education between mTBI patients and healthy controls (P=0.427, P=0.235, P=0.165). The values of MK of the body of corpus callosum (BCC), the genu of corpus callosum (GCC), the splenium of corpus callosum (SCC), the bilateral anterior limb of interbal capsule (ALIP), the right posterior limb of internal capsule (PLIC_R), the bilateral anterior corona radiate (ACR), the bilateral posterior corona radiate (PCR), the bilateral superior corona radiate (SCR), the left inferior fronto-occipital fasciculus (IFOF_L)and the bilateral superior longitudinal fasciculus (SLF) were lower in mTBI patients((1.095±0.080), (1.130±0.066), (1.160±0.080), (1.135±0.077), (1.108±0.076), (1.203±0.069), (1.073±0.056), (1.052±0.055), (1.170±0.055), (1.149±0.050), (1.028±0.056), (1.051±0.059), (0.868±0.060), (1.194±0.048), (1.183±0.054) mm(2)/s) than those in healthy controls((1.153±0.054), (1.184±0.057), (1.215±0.068), (1.181±0.053), (1.163±0.062), (1.258±0.041), (1.115±0.037), (1.096±0.049), (1.210±0.040), (1.190±0.049), (1.063±0.042), (1.087±0.057), (0.913±0.063), (1.236±0.047), (1.214±0.038) mm(2)/s)(P<0.01). However, there were no statistical differences in fractional anisotropy (FA) between groups (P>0.01). Conclusion: DKI technology is more sensitive in detecting cerebral white matter abnormalities in patients with hyperacute mTBI which routine MRI findings was normal.


Assuntos
Concussão Encefálica , Imagem de Tensor de Difusão , Anisotropia , Encéfalo , Corpo Caloso , Humanos , Leucoaraiose , Imageamento por Ressonância Magnética , Rede Nervosa , Substância Branca
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