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1.
Phys Rev Lett ; 132(20): 206401, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38829092

RESUMO

Coexisting orders are key features of strongly correlated materials and underlie many intriguing phenomena from unconventional superconductivity to topological orders. Here, we report the coexistence of two interacting charge-density-wave (CDW) orders in EuTe_{4}, a layered crystal that has drawn considerable attention owing to its anomalous thermal hysteresis and a semiconducting CDW state despite the absence of perfect Fermi surface nesting. By accessing unoccupied conduction bands with time- and angle-resolved photoemission measurements, we find that monolayers and bilayers of Te in the unit cell host different CDWs that are associated with distinct energy gaps. The two gaps display dichotomous evolutions following photoexcitation, where the larger bilayer CDW gap exhibits less renormalization and faster recovery. Surprisingly, the CDW in the Te monolayer displays an additional momentum-dependent gap renormalization that cannot be captured by density-functional theory calculations. This phenomenon is attributed to interlayer interactions between the two CDW orders, which account for the semiconducting nature of the equilibrium state. Our findings not only offer microscopic insights into the correlated ground state of EuTe_{4} but also provide a general nonequilibrium approach to understand coexisting, layer-dependent orders in a complex system.

2.
Zhonghua Zhong Liu Za Zhi ; 46: 1-11, 2024 May 20.
Artigo em Chinês | MEDLINE | ID: mdl-38764329

RESUMO

Objective: To provide supports for the cancer prevention and control strategies in China by comparing the disease burden, epidemic trends, 5-year relative survival rate and major determinants of common cancers between China and the United States. Methods: A descriptive secondary analysis was conducted using data extracted from the GLOBOCAN database, the Surveillance, Epidemiology, and End Results database, Global Burden of disease 2019 database, and previous studies. The main indicators included the cases of malignant tumors in different sites, the cases of deaths, the age-standardized incidence (world standard incidence) and mortality (world standard mortality), the 5-year relative survival rate, and population attributable fraction (PAF). Results: In 2022, an estimated 4.825 million new cases and 2.574 million deaths of malignant neoplasms in China. The world standard incidence rate (201.6/100 000) in China was lower than that in the United States (367.0/100 000), and the world standard mortality rate (96.5/100 000) was higher than that in the United States (82.3/100 000). Lung cancer ranked first in the disease burden of malignant tumors in China, the new cases and deaths accounted for 22.0% and 28.5% of all malignant tumors, respectively. The top three malignant tumors in China were breast cancer (11.5%), prostate cancer (9.7%) and lung cancer (9.5%), which were also among the top five causes of death. However, the second to fifth leading causes of death from malignant tumors in China were digestive system tumors (liver cancer 12.3%, stomach cancer 10.1%, colorectal cancer 9.3%, and esophageal cancer 7.3%). From 2000 to 2018, the world standard incidence of malignant tumors showed an increasing trend and the world standard mortality of malignant tumors showed a decreasing trend in China, while the world standard incidence and mortality of malignant tumors in the United States showed a significant decreasing trend after 2000. The incidence of breast cancer, colorectal cancer and thyroid cancer increased rapidly in China, while the incidence and mortality of stomach cancer, liver cancer and esophageal cancer decreased, but they still had a heavy disease burden. From 2003 to 2015, the overall 5-year relative survival rate of malignant tumors increased from 30.9% to 40.5% in China. However, with the exception of esophageal cancer, the 5-year relative survival rates of other major malignant tumors were lower than those in the United States. In 2019, the PAF of malignant tumors death attributable to potential modifiable risk factors was 48.3% in China, which was similar to the United States (49.8%). Of these, smoking was the most important attributable risk factor, and the PAF was more than 30% both in China and the United States. In addition, about 18.8% of malignant tumors were caused by preventable chronic infections, such as hepatitis B virus and Helicobacter pylori, while less than 4% of malignant tumors in the United States were caused by infection. Conclusions: China has made great progress in the prevention and treatment of malignant tumors, but it still faces a serious disease burden. The cancer spectrum is changing from developing countries to developed countries. We should pay attention to modifiable factors, take comprehensive measures, and prevent cancer scientifically.

3.
Zhonghua Yi Xue Za Zhi ; 104(14): 1132-1137, 2024 Apr 09.
Artigo em Chinês | MEDLINE | ID: mdl-38583042

RESUMO

Objective: To explore the efficacy of short-term personalized vestibular rehabilitation supervised by special personnel (ST-PVR) versus fixed vestibular rehabilitation (FVR) on decompensated recurrent peripheral vertigo. Methods: A randomized controlled trial was carried out. Patients diagnosed with decompensated recurrent vertigo in the clinic of Eye & ENT Hospital, Fudan University from January to December 2018 were randomly allocated into FVR and ST-PVR groups via computer-generated randomization. The FVR group received fixed scheme involving gaze stabilization exercises, habituation exercises, balance and gait training, while the ST-PVR group received individualized training programs based on symptoms and vestibular function examination results, with adjustments made according to the progress of recovery. Patient symptoms and vestibular function improvement were assessed using the dizziness handicap inventory (DHI), activities-specific balance confidence (ABC), self-rating anxiety scale (SAS), caloric test, and sensory organization test (SOT) at 2, 4, and 8 weeks of treatment. Results: A total of 44 patients were included, including 16 males and 28 females, with an average age of (50.6±13.5) years. There were 21 cases in the FVR group and 23 cases in the ST-PVR group. In the ST-PVR group, DHI score (49.5±26.8 vs 61.3±21.4, P=0.046) and SAS score (39.1±7.8 vs 44.3±6.6, P=0.021) significantly improved after 2 weeks of treatment, while significant improvement occurred only after 8 weeks of treatment in the FVR group (DHI score: 28.1±15.9 vs 53.1±18.5, P=0.001; SAS score: 35.3±6.7 vs 43.1±8.4, P=0.010). There was no significant change of ABC score in the FVR group after 8 weeks of treatment (86.5±12.9 vs 83.4±18.1, P=0.373), while a significant improvement was observed in the ST-PVR group after 4 weeks of treatment (83.6±15.2 vs 78.4±15.1, P=0.015). The caloric test results showed that after 8 weeks of treatment, the proportion of patients with unilateral weakness<25% increased in both groups [FVR group: 57.1% (12/21) vs 9.5% (2/21), P=0.001; ST-PVR group: 52.2% (12/23) vs 17.4% (4/23), P=0.014]. In the ST-PVR group, the proportion of patients with dominant preference≤25% significantly increased [91.3% (21/23) vs 60.9% (14/23), P=0.016], while there was no significant change in the FVR group [61.9 (13/21) vs 57.1% (12/21), P=0.500]. The proportion of patients with SOT score≥70 in the ST-PVR group increased significantly after 2 weeks of treatment [69.6% (16/23) vs 30.4% (7/23), P=0.009], while the FVR group showed a significant increase only after 8 weeks of treatment [81.0% (17/21) vs 42.9% (9/21), P=0.012]. Conclusion: Both FVR and ST-PVR effectively promote vestibular compensation by improving objective vestibular functions and relieving subjective symptoms and anxiety of the patients with decompensation recurrent vertigo, while ST-PVR might shorten the recovery time and increase balance confidence.


Assuntos
Tontura , Vestíbulo do Labirinto , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Tontura/diagnóstico , Vertigem/diagnóstico , Terapia por Exercício/métodos , Ansiedade , Equilíbrio Postural
4.
Zhonghua Zhong Liu Za Zhi ; 46(4): 354-364, 2024 Apr 23.
Artigo em Chinês | MEDLINE | ID: mdl-38644271

RESUMO

Objective: To determine the total and age-specific cut-off values of total prostate specific antigen (tPSA) and the ratio of free PSA divided total PSA (fPSA/tPSA) for screening prostate cancer in China. Methods: Based on the Chinese Colorectal, Breast, Lung, Liver, and Stomach cancer Screening Trial (C-BLAST) and the Tianjin Common Cancer Case Cohort (TJ4C), males who were not diagnosed with any cancers at baseline since 2017 and received both tPSA and fPSA testes were selected. Based on Cox regression, the overall and age-specific (<60, 60-<70, and ≥70 years) accuracy and optimal cut-off values of tPSA and fPSA/tPSA ratio for screening prostate cancer were evaluated with time-dependent receiver operating characteristic curve (tdROC) and area under curve (AUC). Bootstrap resampling was used to internally validate the stability of the optimal cut-off value, and the PLCO study was used to externally validate the accuracy under different cut-off values. Results: A total of 5 180 participants were included in the study, and after a median follow-up of 1.48 years, a total of 332 prostate cancer patients were included. In the total population, the tdAUC of tPSA and fPSA/tPSA screening for prostate cancer were 0.852 and 0.748, respectively, with the optimal cut-off values of 5.08 ng/ml and 0.173, respectively. After age stratification, the age specific cut-off values of tPSA in the <60, 60-<70, and ≥70 age groups were 3.13, 4.82, and 11.54 ng/ml, respectively, while the age-specific cut-off values of fPSA/tPSA were 0.153, 0.135, and 0.130, respectively. Under the age-specific cut-off values, the sensitivities of tPSA screening for prostate cancer in males <60, 60-70, and ≥70 years old were 92.3%, 82.0%, and 77.6%, respectively, while the specificities were 84.7%, 81.3%, and 75.4%, respectively. The age-specific sensitivities of fPSA/tPSA for screening prostate cancer were 74.4%, 53.3%, and 55.9%, respectively, while the specificities were 83.8%, 83.7%, and 83.7%, respectively. Both bootstrap's internal validation and PLCO external validation provided similar results. The combination of tPSA and fPSA/tPSA could further improve the accuracy of screening. Conclusion: To improve the screening effects, it is recommended that age-specific cut-off values of tPSA and fPSA/tPSA should be used to screen for prostate cancer in the general risk population.


Assuntos
Detecção Precoce de Câncer , Antígeno Prostático Específico , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/sangue , Antígeno Prostático Específico/sangue , Idoso , Pessoa de Meia-Idade , Detecção Precoce de Câncer/métodos , Fatores Etários , Curva ROC , China , Sensibilidade e Especificidade , Programas de Rastreamento/métodos , Área Sob a Curva
5.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(4): 676-683, 2023 Aug 18.
Artigo em Chinês | MEDLINE | ID: mdl-37534651

RESUMO

OBJECTIVE: To evaluate the effect of equal temperature bladder irrigation on bladder spasm, postoperative bleeding, vital signs and discomfort of chills in patients of transurethral resection of prostate using meta-analysis. METHODS: Several electronic databases included Cochrane Library, PubMed, Embase, China National Knowledge Infrastructure (CNKI), Wanfang, VIP, China Biology Medicine (CBM) were searched systematically for published randomized controlled trial about equal temperature bladder irrigation in patients with transurethral resection of prostate before November 20, 2019. Two reviewers selected independently the literature in the light of the inclusion and exclusion criteria, assessed the risk of bias by quality assessment and extracted data which were consisted of clinical efficacy indexes, such as incidence of bladder spasm, severity of bladder spasm, incidence of tube plugging, amount of bladder flushing fluid, time of bladder flushing, heart rate, systolic pressure, diastolic pressure, and incidence of chills. Data were pooled using fixed-effects model or random-effects model, and the summary effect measure was calculated by risk ratio (RR) or mean difference (MD) and 95% confidence interval (95%CI). Meta-analysis was performed by Review Manager 5.3 Software. RESULTS: In the study, 13 randomized controlled trails met the requirement with a total of 2 033 patients of transurethral resection of prostate were included, of whom 1 015 were carried out with equal temperature bladder irrigation and 1 018 with room temperature bladder irrigation. The results of meta-analysis showed that incidence of bladder spasm [RR=0.51, 95%CI (0.45, 0.57), P < 0.001], severity of bladder spasm [MD=-1.61, 95%CI (-2.00, -1.23), P < 0.001], incidence of urinary blockage [RR=0.29, 95%CI (0.19, 0.44), P < 0.001], dosage of bladder irrigation [MD=-6.75, 95%CI (-7.33, -6.17), P < 0.001], time of bladder rinse [MD=-7.60, 95%CI (-11.91, -3.29), P < 0.001], heart rate [MD=-13.68, 95%CI (-15.19, -12.17), P < 0.001], systolic pressure [MD=-29.26, 95%CI (-31.92, -26.59), P < 0.001], diastolic pressure [MD=-29.36, 95%CI (-31.75, -26.98), P < 0.001], incidence of chills and discomfort [MD=0.37, 95%CI (0.31, 0.44), P < 0.001] in equal temperature group of the patients with transurethral resection of prostate had significantly statistical difference compared with room temperature group. CONCLUSION: Based on current available evidence, equal temperature bladder irrigation reduced the incidence of bladder spasm and urinary blockage, relieved bladder spasm, reduced dosage and time of bladder irrigation, and hardly affected normal vital signs and increased the patient' s comfort.


Assuntos
Hiperplasia Prostática , Ressecção Transuretral da Próstata , Masculino , Humanos , Ressecção Transuretral da Próstata/efeitos adversos , Ressecção Transuretral da Próstata/métodos , Bexiga Urinária/cirurgia , Calafrios , Temperatura , Hiperplasia Prostática/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Beijing Da Xue Xue Bao Yi Xue Ban ; 54(4): 621-627, 2022 Aug 18.
Artigo em Chinês | MEDLINE | ID: mdl-35950383

RESUMO

OBJECTIVE: To investigate the correlation between drinking habits and pathological characteristics of patients with upper tract urothelial carcinoma (UTUC). METHODS: A preoperative questionnaire survey was conducted to understand the drinking habits of UTUC patients who were admitted to the Department of Urology, Peking University First Hospital for radical nephroureterectomy within one year from August 2020 to July 2021, and statistical analysis was performed in combination with their postoperative pathological characteristics. The statistical procedure was performed using SPSS 22.0 software, and firstly, the preliminary analysis was performed one by one using the columnar χ2 test on the pathological characteristics of UTUC tumors as the dependent variable and the factors related to patients' general information, past history and drinking habits as the independent variables, and the independent variables that met P < 0.2 between the case and control groups for each dependent variable were specified for screening. The screened variables were included in the binary Logistic regression analysis. A difference of P < 0.05 was used to indicate a statistically significant difference. RESULTS: A total of 239 patients, 134 males and 105 females, with a mean age of (68.1±9.98)years and a median disease duration of 4.8 months, were included in this study. Multifactorial Logistic regression results suggested that after adjusting for the effects of other variables, UTUC patients who had the habit of drinking at least once every hour during the daytime had a significantly increased risk of high grade (G3) tumors(OR=1.941, 95%CI: 0.352-1.029, P < 0.01); these patients also had a significantly decreased risk of multifocal UTUC tumors (OR=0.344, 95% CI: 1.18-5.582, P=0.004). The patients who had the habit of drinking over 100 mL water each time had a significantly decreased risk of mutifocal UTUC incidence (OR=0.477, 95%CI: 0.225-1.012, P=0.046). Patients who pay attention to daily water intakes had a significantly increased risk of renipelvic carcinoma (OR=2.530, 95%CI: 1.434-4.463, P=0.001) and a significantly decreased risk of ureteral carcinoma (OR=0.314, 95%CI: 0.172-0.573, P < 0.01). Other variables included in the regression model did not differ significantly in their effects on the occurrence of tumor pathological characteristics. CONCLUSION: Having the awareness of drinking water every 1 h during the day, drinking over 100 mL water each time, having the awareness of daily drinking habits correlated significantly with pathological characteristics of UTUC such as the presence of G3 tumor, multifocal tumors and location of the tumor. This conclusion still needs to be verified by subsequent trials with higher levels of evidence.


Assuntos
Carcinoma de Células de Transição , Neoplasias Ureterais , Neoplasias da Bexiga Urinária , Carcinoma de Células de Transição/cirurgia , Feminino , Hábitos , Humanos , Masculino , Recidiva Local de Neoplasia/epidemiologia , Estudos Retrospectivos , Neoplasias Ureterais/epidemiologia , Neoplasias Ureterais/cirurgia , Neoplasias da Bexiga Urinária/cirurgia , Água
7.
Phys Rev Lett ; 128(3): 036401, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35119886

RESUMO

Hysteresis underlies a large number of phase transitions in solids, giving rise to exotic metastable states that are otherwise inaccessible. Here, we report an unconventional hysteretic transition in a quasi-2D material, EuTe_{4}. By combining transport, photoemission, diffraction, and x-ray absorption measurements, we observe that the hysteresis loop has a temperature width of more than 400 K, setting a record among crystalline solids. The transition has an origin distinct from known mechanisms, lying entirely within the incommensurate charge density wave (CDW) phase of EuTe_{4} with no change in the CDW modulation periodicity. We interpret the hysteresis as an unusual switching of the relative CDW phases in different layers, a phenomenon unique to quasi-2D compounds that is not present in either purely 2D or strongly coupled 3D systems. Our findings challenge the established theories on metastable states in density wave systems, pushing the boundary of understanding hysteretic transitions in a broken-symmetry state.

8.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(12): 1524-1529, 2021 Dec 06.
Artigo em Chinês | MEDLINE | ID: mdl-34963255

RESUMO

The traditional proportional hazard model is commonly used to investigate the association between main outcome and predictor variables. However, the endpoints in medical studies are often not unique. The analyses of labeling other competing outcomes other than the main outcome as censored data will theoretically lead to a biased estimate of the risk of main outcome. Although the traditional competitive risk model can adjust the influence of other outcomes on the risk of the main outcome, it can not directly compare the differences on the risks of different outcomes. The multi-state competing risk model provides a relatively suitable solution for this problem. In this study, based on a previously published follow-up data set for prostate cancer patients, we developed traditional proportional hazard model, traditional competitive risk model, and multi-state competing risk model, respectively. By comparing the advantages and disadvantages of the three models with the same survival data, we clarified the clinical application value of the multi-state competitive risk model in survival data with multiple outcomes.


Assuntos
Neoplasias da Próstata , Humanos , Masculino , Modelos de Riscos Proporcionais , Risco , Medição de Risco , Fatores de Risco , Análise de Sobrevida
9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(10): 1203-1208, 2021 Oct 06.
Artigo em Chinês | MEDLINE | ID: mdl-34706505

RESUMO

Objective: To investigate the potential pleiotropism of cancer-related single nucleotide polymorphisms (SNPs) among Chinese population. Methods: Based on the catalogue of GWAS jointly constructed by the National Human Genome Research Institute and the European Institute of Bioinformatics, according to population origin (Chinese population and non-Chinese population) and disease traits (cancer and non-cancer traits). All SNPs found by GWAS before August 2020 were divided into four categories: cancer in Chinese population, non-cancer in Chinese population, cancer in non-Chinese population and non-cancer in non-Chinese population. The number, correlation and linkage of the four categories of SNPs were described. Results: By August 2020, a total of 196 813 SNPs from 4 096 GWAS were included in the GWAS directory. The information that SNPs refer to unknown or were not related to the disease was excluded, and 117 441 independent SNPs were finally included. There were 619 SNPs related to cancer and 9 569 SNPs related to non-cancer disease in Chinese population, respectively. There were 4 624 SNPs related to cancer and 106 448 SNPs related to non-cancer disease (trait) in non-Chinese population, respectively. Three SNPs, rs2736100, rs6983267 and rs401681, were associated with two or more types of cancer in both Chinese and non-Chinese populations. Seven SNPs, rs7705526, rs2736100, rs10993994, rs2735839, rs4430796, rs174537 and rs9271588, were associated with cancer and non-cancer diseases in both Chinese and non-Chinese populations, respectively. Conclusion: There is a potential pleiotropism of cancer-related SNPs in Chinese population.


Assuntos
Neoplasias , Polimorfismo de Nucleotídeo Único , China , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Neoplasias/genética , Fenótipo
10.
Zhonghua Yi Xue Za Zhi ; 101(26): 2044-2049, 2021 Jul 13.
Artigo em Chinês | MEDLINE | ID: mdl-34275236

RESUMO

Objective: To explore the prognosis of individualized vestibular rehabilitation (VR) in patients with intractable vertigo and work out an effective and normative rehabilitation program. Methods: A total of 35 patients diagnosed with intractable vertigo who visited Eye & ENT Hospital of Fudan University from September 2017 to December 2019 were enrolled. All the participants consisted of 15 males and 20 females, aged from 24 to 71 years old, and underwent an individualized VR. Follow-ups were conducted at 2 and 4 weeks post-rehabilitation. Assessments consisted of self-rating anxiety scale (SAS), dizziness handicap inventory scale (DHI), activities-specific balance confidence sacle (ABC), computerized dynamic posturography (CDP), and video-electronystagmograph (VNG) were performed. Results: SAS, DHI, ABC scores gradually improved after VR. The scores of SAS scale of pre-VR, 2 and 4 weeks post-VR were 41±8, 37±8 and 36±8, respectively. The scores of DHI were 56(40, 78), 46(22, 74), 16(6, 76), respectively. Meanwhile, the scores of ABC were 80±17, 87±11 and 91±9, respectively. There were significant statistical differences of aforementioned three scale scores at different time points (P=0.020, P<0.01, P=0.002), which was not influenced by age and gender (all P>0.05). No interactive effects were revealed among age, gender and time (all P>0.05). The improvement of vestibular function to control balance was statistically significant after 2-and 4-week rehabilitation (both P<0.001). The value of directional preponderance was significantly improved after 4-week VR (P=0.007), while no obvious improvement was found after 2 weeks treatment (P=0.593). There was a statistically significant difference in the value of unilateral weakness (UW) between pre-VR and post-VR since 2 weeks (P=0.001). Conclusion: Individualized VR in patients with intractable vertigo can not only eliminate anxiety, control dizziness, increase activities of daily life, but also improve the function of vestibulo-spinal and vestibulo-ocular reflex pathways.


Assuntos
Vertigem , Vestíbulo do Labirinto , Adulto , Idoso , Ansiedade , Tontura , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Equilíbrio Postural , Adulto Jovem
11.
Poult Sci ; 100(7): 101096, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34087700

RESUMO

The aim of this study was to evaluate the effects of dietary phytosterol (PS) addition at different levels on growth performance, serum lipid, proinflammatory cytokines, intestinal morphology, and meat quality in broilers. A total of 600, 1-day-old male broilers were allocated into five groups with six replicates and were fed a basal diet supplemented with 0 (control group), 10, 20, 40, or 80 mg/kg PS for 42 days. Compared with the control group, the administration of PS at doses of 40 and 80 mg/kg significantly increased the average daily feed intake and average daily gain of broilers during the experimental period. Similarly, PS at a dosage of 20 and 40 mg/kg increased the concentrations of interleukin-1ß, interferon-γ, interleukin-2, and interleukin-6 but decreased triglyceride, total cholesterol, and low-density lipoprotein cholesterol content of serum (P < 0.05). Dietary PS at less than or equal to 40 mg/kg level increased (P < 0.05) villus height, and villus height to crypt depth ratio in the duodenum and ileum. Supplementing PS increased the pH value at 45 min post-mortem and decreased drip loss and shear force of breast muscle (P < 0.05). Dietary PS administration at 20 and 40 mg/kg decreased malondialdehyde accumulation but increased total antioxidant capacity and superoxide dismutase activity of breast muscle compared with the control group (P < 0.05). PS increased the concentrations of total amino acids and flavor amino acids as well as eicosapentaenoic acid, docosahexaenoic acid, and total polyunsaturated fatty acids but decreased saturated fatty acids in breast muscle (P < 0.05). It was concluded that dietary PS supplementation, especially at 40 mg/kg, could improve growth performance, serum lipid, proinflammatory cytokines, intestinal morphology, and meat quality in broilers, providing insights into its application as a potential feed additive in broiler production.


Assuntos
Galinhas , Fitosteróis , Ração Animal/análise , Animais , Antioxidantes , Citocinas , Dieta , Suplementos Nutricionais , Plumas , Masculino , Carne/análise
13.
Nat Mater ; 19(1): 27-33, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31591532

RESUMO

One or a few layers of van der Waals (vdW) materials are promising for applications in nanoscale electronics. Established properties include high mobility in graphene, a large direct gap in monolayer MoS2, the quantum spin Hall effect in monolayer WTe2 and so on. These exciting properties arise from electron quantum confinement in the two-dimensional limit. Here, we use angle-resolved photoemission spectroscopy to reveal directional massless Dirac fermions due to one-dimensional confinement of carriers in the layered vdW material NbSi0.45Te2. The one-dimensional directional massless Dirac fermions are protected by non-symmorphic symmetry, and emerge from a stripe-like structural modulation with long-range translational symmetry only along the stripe direction as we show using scanning tunnelling microscopy. Our work not only provides a playground for investigating further the properties of directional massless Dirac fermions, but also introduces a unique component with one-dimensional long-range order for engineering nano-electronic devices based on heterostructures of vdW materials.

14.
Zhonghua Wei Chang Wai Ke Za Zhi ; 22(10): 977-983, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-31630497

RESUMO

Objective: To explore the value of dual-energy CT-based volumetric iodine-uptake (VIU) in the evaluation of chemotherapy efficacy in advanced gastric cancer. Methods: Inclusion criteria of subjects: (1) without previous systematic therapy; (2) with complete clinical information before and after chemotherapy; (3) without contraindications of chemotherapy. Exclusion criteria of subjects: (1) unfinished duration and times of chemotherapy; (2) unmeasurable primary lesions; (3) poor imaging quality or poor gastric filling. Clinical and image data of 52 patients with advanced gastric cancer who were diagnosed by pathology from gastroscopic biopsy, and needed chemotherapy evaluated by imaging and clinical information in the First Affiliated Hospital of Wenzhou Medical University from February 2017 to February 2018 were collected and analyzed. Of 52 patients, 38 were male and 14 were female with the median age of 65 (31-88) years old. All the patients underwent a dual-energy, dual phase-enhanced CT scanning before chemotherapy and after the third chemotherapy session. The parameters of the lesions measured before and after chemotherapy in portal vein phase were as follows: the maximum diameter (the largest diameter among those measured in the cross-sectional, coronal, and sagittal planes), average CT value (the regions of interest were manually pinpointed under cross-sectional planes with largest diameter of the tumor, which did not include regions less than 2 mm to the edge of the tumor) and VIU (lesion volume × iodine concentration). The change rates of maximum lesion diameter, average CT value and VIU before and after chemotherapy were calculated [(post-chemotherapy parameters-pre-chemotherapy parameters)/ pre-chemotherapy parameters]. The efficacy of chemotherapy was evaluated by RECIST 1.1 (the change of maximum tumor diameter after chemotherapy), Choi (the change of average CT value after chemotherapy) and VIU (the change of VIU after chemotherapy), respectively, which was categorized by complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). Patients with CR, PR, and SD were assigned to the effective group, while those with PD were classified as the ineffective group. Paired t - test or Wilcoxon signed ranks test was used to compare the changes of parameters before and after chemotherapy, whereas Spearman correlation analysis and Kappa test were used for the correlation analysis and the consistency test between the three evaluation criteria (Kappa≥0.75 indicated good consistency). Results: After chemotherapy, the average CT value [(74.01±16.75) HU vs. (81.06±15.87) HU, t=2.202, P=0.030] and median VIU (668.53×10(2) µg vs. 272.52×10(2) µg, Z=4.761, P<0.001) decreased significantly, while the difference of the maximum diameter was not statistically significant [(66.71±34.49) mm vs. (78.45±35.62) mm, t=1.708, P=0.091]. The median change rate of VIU (-53.33%) was greater than that of CT values (-5.75%) with significant difference (Z=-5.408, P<0.001). According to the RECIST 1.1 criteria, 47 patients (90.4%, including 19 with PR and 28 with SD) were effective and 5 patients (9.6%) were ineffective. According to the Choi criteria, 45 patients (86.5%, including 37 with PR and 8 with SD) were effective and 7 patients (13.5%) were ineffective. According to the VIU criteria, 46 patients (88.5%, including 41 with PR and 5 with SD) were effective and 6 patients (11.5%) were ineffective. Efficacy comparison among these three criteria showed no significant difference (χ(2)=0.377, P=0.828). As compared to RECIST 1.1 evaluation, the proportion of PR evaluated by Choi and VIU was significantly higher (χ(2)=16.861, P<0.001), whereas the proportion of SD was significantly lower (χ(2)=24.089, P<0.001). There was no significant difference in the proportions of PR and SD between VIU and Choi criteria (χ(2)=0.887, P=0.346). Consistency and correlation analysis showed that the VIU and Choi evaluation criteria presented the highest consistency and correlation (Kappa=0.912, P<0.001; r=0.916, P<0.001). Conclusion: VIU is a feasible parameter for the evaluation of chemotherapy efficacy in advanced gastric cancer, and may be more sensitive than the evaluation criteria based on maximum diameter or change of CT value in the tumor.


Assuntos
Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/tratamento farmacológico , Tomografia Computadorizada por Raios X/métodos , Absorciometria de Fóton , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Radioisótopos do Iodo/farmacologia , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/farmacologia , Indução de Remissão , Neoplasias Gástricas/patologia , Resultado do Tratamento
15.
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.

16.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(4): 706-710, 2019 Aug 18.
Artigo em Chinês | MEDLINE | ID: mdl-31420626

RESUMO

OBJECTIVE: To explore risk factors of urinary incontinence (UI) and influences of UI on quality of life in female medical staff from Beijing. METHODS: One hundred and forty-six female medical personnel were included in the present study through the convenient sampling method in Peking University First Hospital. The questionnaires contained the following information: demographic information, daily urination condition, the severity of UI [international consultation on incontinence questionnaire short form (ICI-Q-SF)], and the influences of UI on quality of life (QOL). We excluded the subjects who were in pregnancy or had urinary infection, neurogenic bladder, or urethral stricture. We used SPSS 21.0 software (IBM Corp, Armonk, NY) for statistical analysis. The Kolmogorov-Smirnov test determined the normality of the continuous variables. Means and standard deviation presented continuous variables in normality. Median and range presented continuous variables without normality. Frequency and percentile were used to present categorical or ranked variables. RESULTS: There were 63 out of 146 (43.2%) female medical staff suffering from UI. The mean age and body mass index of the whole study cohort were (39.4±9.9) years and (22.3±3.4) kg/m2. The median delivery times of all the subjects were 1 time (range: 0-3 times). Fifty out of 146 (34.2%) subjects had transvaginal delivery history. Chronic constipation was diagnosed in 32 subjects (21.9%). No significant difference in daytime micturition and nocturia times were found between the UI and non-UI subjects. According to the multivariate analysis, chronic constipation (OR=4.95, 95%CI=1.81-13.53, P=0.002) and transvaginal delivery history (OR=3.50, 95%CI=1.49-8.21, P=0.004) were independent risk factors for UI. The non-UI subjects had superior quality of life than the UI subjects in terms of incontinence quality of life (I-QOL) total scores and all sub-scores of avoidance and limiting behaviors, psychosocial impacts, and social embarrassment (P<0.001). In addition, avoidance and limiting behaviors (r=-0.449, P<0.001), psychosocial impacts (r=-0.538, P<0.001), and social embarrassment (r=-0.454, P<0.001) of the 63 UI subjects were equally influenced by the incontinence symptom. CONCLUSION: UI is not uncommon in female medical staff. The quality of life of medical faculty is influenced by UI in terms of avoidance and limiting behaviors, psychosocial impacts, and social embarrassment. Chronic constipation and transvaginal delivery history were independent risk factors for UI.


Assuntos
Qualidade de Vida , Incontinência Urinária , Adulto , Feminino , Humanos , Corpo Clínico , Pessoa de Meia-Idade , Gravidez , Fatores de Risco , Inquéritos e Questionários
17.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(6): 713-718, 2019 Jun 10.
Artigo em Chinês | MEDLINE | ID: mdl-31238625

RESUMO

Objective: To investigate the potential application values of screening on breast cancer, using the single-nucleotide polymorphisms (SNPs) that were identified from the genome- wide association studies (GWASs). Methods: Two million Chinese women aged 35-69 years were simulated, based on both age distributions, age-specific incidence rates of breast cancer and the distribution of known risk factors, in 2013. Twenty-three SNPs identified from GWAS were further simulated. Both genetic-related risks explained by each SNPs and the improvement on the risks under reclassification, were used to select SNPs for the prediction on breast cancer among the targeted high-risk population. Further analyses were conducted to investigate the following items as: improvements on detection rates of breast cancer among the high-risk populations, areas under the curve (AUC) and the odds ratio (OR) among women at high risk. Results: A total of 12 SNPs were eligible for targeting the high-risk population of breast cancer. When high-risk populations were defined as women whose predicted risks were higher than the 95(th) predicted risk of the whole population, the detection rate (146.99/100 000) among high-risked women predicted by 12 SNPs would be significantly lower than 177.46/100 000, which was predicted by the known risk factors (P<0.001), among the high-risked women. Among those women at high risk, the detection rate (229.00/100 000) predicted by integrating known risk factors and 12 SNPs was significantly higher than that predicted by known risk factors (P<0.001). Also, the AUC increased from 64.4% to 67.8% (P<0.001), and the OR of increased from 3.32 to 4.33, predicted by integrating known risk factors and 12 SNPs, for women at high risk on breast cancer. Conclusion: Targeted SNPs that were identified from genome- wide association studies could be used to improve the detection rates as well as the overall accuracy of risk prediction so as to identify the potential high-risk women on breast cancer before carrying on the screening program.


Assuntos
Povo Asiático/genética , Neoplasias da Mama/genética , Detecção Precoce de Câncer/métodos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso , Área Sob a Curva , Neoplasias da Mama/diagnóstico por imagem , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco
18.
Sci Adv ; 5(5): eaau6459, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31058219

RESUMO

Topological semimetals are characterized by symmetry-protected band crossings, which can be preserved in different dimensions in momentum space, forming zero-dimensional nodal points, one-dimensional nodal lines, or even two-dimensional nodal surfaces. Materials harboring nodal points and nodal lines have been experimentally verified, whereas experimental evidence of nodal surfaces is still lacking. Here, using angle-resolved photoemission spectroscopy (ARPES), we reveal the coexistence of Dirac nodal surfaces and nodal lines in the bulk electronic structures of ZrSiS. As compared with previous ARPES studies on ZrSiS, we obtained pure bulk states, which enable us to extract unambiguously intrinsic information of the bulk nodal surfaces and nodal lines. Our results show that the nodal lines are the only feature near the Fermi level and constitute the whole Fermi surfaces. We not only prove that the low-energy quasiparticles in ZrSiS are contributed entirely by Dirac fermions but also experimentally realize the nodal surface in topological semimetals.

19.
Zhonghua Yi Xue Za Zhi ; 99(12): 943-946, 2019 Mar 26.
Artigo em Chinês | MEDLINE | ID: mdl-30917446

RESUMO

Objective: To evaluate the prognosis and surgical complication of the recanalization treatments for internal carotid artery (ICA) occlusion by using one-step hybrid carotid endarterectomy and endovascular surgery. Methods: Retrospective analysis was performed on the clinical data and follow-up data of 22 patients with occluded ICA treated by one-step hybrid surgery. Difference in Barthel score and occurrence of ischemic stroke were compared with surgical group and conventional group which was treated by oral taking anti-platelet drugs. Further, the complications were analyzed to evaluate the safety and effectiveness of the surgery. Results: The difference in ischemic event rate and Barthel scores improvement between the two groups were significant. Occlusive ICAs in 19 cases were recanalized successfully. The possibility of brain hyperperfusion related to the surgery was 10.5% (2/19) while the possibility of carotid artery cavernous fistula was 9.1% (2/22). We also observed rare dissecting ICA caused by the treatment (4.5%) and distal restenosis (5.3%). Conclusions: One-step hybrid carotid endarterectomy and endovascular surgery could help recanalize the ICA, improve the blood supply and improve the prognosis. It's a safe and effective treatment for ICA occlusion.


Assuntos
Estenose das Carótidas , Endarterectomia das Carótidas , Artéria Carótida Interna , Estenose das Carótidas/cirurgia , Humanos , Estudos Retrospectivos , Stents , Resultado do Tratamento
20.
Artigo em Chinês | MEDLINE | ID: mdl-29996252

RESUMO

Objective: To know the incidence of heat stroke and explore it's prediction model in Pudong New Area of Shanghai. Methods: An epidemiological investigation was conducted on heat stroke cases in Pudong New Area of Shanghai from 2013 to 2017. Daily temperature data during this period were collected to explore it's influence. Results: 246 heat stroke cases were reported and investigated, 70.3% (173/246) of them were male. 170 cases are severe heat stroke, accounting for 69.1%. 28 patients died, accounting for 11.4% of all cases of heat stroke, and 16.5% (28/170) of severe heat stroke cases. Thermoplegia (56.5%, 96/170) was the most popular type among severe heat stroke cases. Heat prostration, heat cramps and mixed type account for 17.1% (29/170) , 12.4% (21/170) and 14.0% (24/170) respectively. Scatter plot and linear regression demonstrated that there was a significant linear relation between number of high temperature days and number of heat stroke cases (P<0.01) . And the prediction model is: Predictive number of annual heat stroke cases=ß×Number of annual high temperature days+Intercept. Leave-one-out cross validation result shows that the predictive number of annual heat stroke cases from 2013 to 2017 were 85.7%, 90.9%, 83.3%, 91.9 and 84.3% respectively. Conclusion: There was a significant linear relation between number of high temperature days and number of heat stroke cases in Pudong New Area. The related work arrangement for heat stroke prevention could be well planed according to the prediction model.


Assuntos
Golpe de Calor/epidemiologia , Temperatura Alta , China , Humanos , Incidência , Masculino , Temperatura
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