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1.
Front Cardiovasc Med ; 9: 1012095, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36531702

RESUMO

Aims: To investigate the risk factors, clinical features, and prognostic factors of patients with premature acute myocardial infarction (AMI). Materials and methods: A retrospective cohort study of patients with AMI included in data from the West China Hospital of Sichuan University from 2011 to 2019 was divided into premature AMI (aged < 55 years in men and < 65 years in women) and non-premature AMI. Patients' demographics, laboratory tests, Electrocardiography (ECG), cardiac ultrasound, and coronary angiography reports were collected. All-cause death after incident premature MI was enumerated as the primary endpoint. Results: Among all 8,942 AMI cases, 2,513 were premature AMI (79.8% men). Compared to the non-premature AMI group, risk factors such as smoking, dyslipidemia, overweight, obesity, and a family history of coronary heart disease (CHD) were more prevalent in the premature AMI group. The cumulative survival rate of patients in the premature AMI group was significantly better than the non-premature AMI group during a mean follow-up of 4.6 years (HR = 0.27, 95% CI 0.22-0.32, p < 0.001). Low left ventricular ejection fraction (LVEF) (Adjusted HR 3.00, 95% CI 1.85-4.88, P < 0.001), peak N-terminal pro-B-type natriuretic peptide (NT-proBNP) level (Adjusted HR 1.34, 95% CI 1.18-1.52, P < 0.001) and the occurrence of in-hospital major adverse cardiovascular and cerebrovascular events (MACCEs) (Adjusted HR 2.36, 95% CI 1.45-3.85, P = 0.001) were predictors of poor prognosis in premature AMI patients. Conclusion: AMI in young patients is associated with unhealthy lifestyles such as smoking, dyslipidemia, and obesity. Low LVEF, elevated NT-proBNP peak level, and the occurrence of in-hospital MACCEs were predictors of poor prognosis in premature AMI patients.

2.
Inorg Chem ; 60(12): 8461-8474, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34096279

RESUMO

The built-in electric field generated by polar materials is one of the most effective strategies to promote the separation of photogenerated electron-hole pairs in the field of photocatalysis. However, because of the complexity and diversity of the built-in electric field in polar materials, it is not clear how to enhance the photocatalytic performance and how to control the polar electric field effectively. To this end, four-layered bismuth oxyhalides, BiOX, and BiOXO3 (X = Br, I) were synthesized by a simple hydrothermal method. X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy analysis confirmed that they all have the structure characteristics of a sillenite phase. Scanning electron microscopy images show that they all have the morphology of nanosheets. Among them, BiOBrO3 was successfully synthesized and characterized for the first time in the present work. The order of photocatalytic performance (including carrier's lifetime, photocurrent density, and H2 evolution rate) of the four compounds is listed as follows: BiOBrO3 > BiOI > BiOIO3 > BiOBr. In the bulk of the BiOXO3 photocatalyst, the spontaneous polar built-in electric field along the [001] direction is the crucial factor to inhibit the recombination of photogenerated electron-hole pairs, while the surface polar electric field in BiOI can outstandingly inhibit the recombination of photogenerated electron-hole pairs due to the breaking of the mirror symmetry. Therefore, regulating the microstructure and composition of the structure unit, which generates the built-in electric field, can indeed control the magnitude, direction, and effects of built-in electric fields. In practice, we should carefully adjust the strategy according to the actual situation so as to reasonably design and use the polar electric field, giving full play to its role and enhancing the photocatalytic performance.

3.
Inorg Chem ; 59(22): 16679-16689, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33124821

RESUMO

Hydrothermal and solid-state reaction methods are commonly used to prepare the delafossite CuCrO2 photocatalyst. It has been reported that the photocatalytic performances of CuCrO2 samples prepared by these methods are quite different. In order to explore the possible influence of different preparation processes on the photocatalytic performance and the corresponding improvement strategies, this work compares the microstructure and physicochemical properties of the samples prepared by these two methods on the basis of optimizing the process conditions. A CuCrO2 sample prepared by a hydrothermal method is characterized by high purity, low crystallinity, small grain size, and relatively higher photocatalytic activity. A CuCrO2 sample prepared by a solid-state reaction method is characterized by low purity, high crystallinity, large grain size, and relatively lower photocatalytic activity. In combination with DFT calculations, it is confirmed that the CuCrO2 sample prepared by a solid-state reaction method contains a certain amount of interstitial oxygens. Due to the presence of interstitial oxygens, CuCrO2 has strong light absorption in the visible region, presents semimetallic ferromagnetism, and changes the carrier transport, reaction process, and rate on the electrode surface. These findings will contribute to the further development of efficient CuCrO2-based photocatalysts.

4.
Chem Commun (Camb) ; 47(42): 11766-8, 2011 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-21952713

RESUMO

A stable zwitterionic radical can catalyze direct arylation of unactivated aromatic C-H bonds via a chain homolytic aromatic substitution mechanism in the presence of potassium tert-butoxide.

5.
Dalton Trans ; 40(16): 4131-9, 2011 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-21384049

RESUMO

The preparation, X-ray crystallography, EPR, magnetic and luminescent investigation of new metal-anion radical framework materials based on a new anion radical ligand generated by in situ deprotonation of a stable zwitterionic radical are described herein. N,O,N-tripodal anion radical ligand (bipo(-)˙) links metal cations, giving rise to four isostructural one-dimensional metal-organic frameworks, [M(bipo(-)˙)(L)](n) [M = Zn, L = HCOO(-) (1), SCN(-) (1a), N(3)(-) (1b); M = Co, L = Br(-) (3)]. The tripodal bipo(-)˙ ligand and one co-ligand, 1,4-benzenedicarboxylate, coordinate to metals leading to two isostructural two-dimensional metal-organic frameworks, [M(bipo(-)˙)(BDC)(0.5)](n) [M = Zn (2) and Co (4)]. The two Co(II) compounds are the first examples that exhibit unusual ferromagnetic to antiferromagnetic phase transition with transition temperature over room temperature, which can be demonstrated by the cooling and warming measurements of susceptibility. Compound 4 also exhibits long-range magnetic ordering with the critical temperature at about 44 K proved by ac susceptibility measurements. The metal-radical frameworks exhibit distinctly different fluorescence emissions. Especially, the isomorphous one-dimensional Zn(II) compounds show interesting terminal anion ligand-induced photoluminescent color changes, including direct and invariable white-light-emission with terminal SCN(-) ligand.

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