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1.
Zhen Ci Yan Jiu ; 45(1): 62-5, 2020 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-32144911

RESUMO

OBJECTIVE: To investigate the clinical effect of acupoint thread-embedding therapy at different intervals in the treatment of metabolic syndrome, and to find the optimal treatment interval. METHODS: A total of 70 patients with metabolic syndrome were randomly divided into treatment group 1 (n=35)and treatment group 2(n=35). Both groups were given acupoint thread-embedding therapy at Zhongwan (CV12), bilateral Liangmen (ST21), bilateral Huaroumen (ST24), bilateral Tianshu (ST25), bilateral Daimai (GB26), Guanyuan (CV4), bilateral Dachangshu (BL25), bilateral Pishu (BL20), bilateral Zusanli (ST36), bilateral Yinlingquan (SP9), and bilateral Fenglong (ST40), and the treatment interval was 7 d for treatment group 1 and 14 d for treatment group 2. Each course of treatment was 42 d, and both groups were treated for 2 courses. Waist circumfe-rence (WC), hip circumference (HC), waist-hip ratio (WHR), body mass index (BMI), serum triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), fasting plasma glucose (FPG), and glycosylated hemoglobin (Hb1Ac) were measured before and after treatment to analyze clinical outcome, and adverse reactions were recorded. RESULTS: After treatment, both groups had significant reductions in WC, HC, WHR, BMI, TG, LDL-C, FPG and Hb1Ac (P<0.05) and a significant increase in HDL-C (P<0.05). Compared with treatment group 1, treatment group 2 had significant increases in WC, WHR, BMI, TG, LDL-C, FPG and Hb1Ac (P<0.05) and a significant reduction in HDL-C (P<0.05). There was no significant difference in the incidence rate of adverse reactions between the two groups (P>0.05). CONCLUSION: Under the premise of ensuring efficacy and safety, an interval of 7 d is the optimal interval for acupoint thread-embedding therapy in the clinical intervention of metabolic syndrome.


Assuntos
Pontos de Acupuntura , Síndrome Metabólica , Índice de Massa Corporal , Humanos , Síndrome Metabólica/terapia , Relação Cintura-Quadril
2.
Sci Rep ; 6: 25453, 2016 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-27140674

RESUMO

Ge-Sb-Te alloys have been widely used in optical/electrical memory storage. Because of the extremely fast crystalline-amorphous transition, they are also expected to play a vital role in next generation nonvolatile microelectronic memory devices. However, the distribution and structural properties of vacancies have been one of the key issues in determining the speed of melting (or amorphization), phase-stability, and heat-dissipation of rock-salt GeSbTe, which is crucial for its technological breakthrough in memory devices. Using spherical aberration-aberration corrected scanning transmission electron microscopy and atomic scale energy-dispersive X-ray mapping, we observe a new rock-salt structure with high-degree vacancy ordering (or layered-like ordering) at an elevated temperature, which is a result of phase transition from the rock-salt phase with randomly distributed vacancies. First-principles calculations reveal that the phase transition is an energetically favored process. Moreover, molecular dynamics studies suggest that the melting of the cubic rock-salt phases is initiated at the vacancies, which propagate to nearby regions. The observation of multi-rock-salt phases suggests another route for multi-level data storage using GeSbTe.

3.
Nano Lett ; 16(2): 1156-60, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26799861

RESUMO

Sublimation is an important endothermic phase transition in which the atoms break away from their neighbors in the crystal lattice and are removed into the gas phase. Such debonding process may be significantly influenced by dislocations, the crystal defect that changes the bonding environment of local atoms. By performing systematic defects characterization and in situ transmission electron microscopy (TEM) tests on a core--shell MgO-Mg system, which enables us to "modulate" the internal dislocation density, we investigated the role of dislocations on materials' sublimation with particular focus on the sublimation kinetics and mechanism. It was observed that the sublimation rate increases significantly with dislocation density. As the density of screw dislocations is high, the intersection of screw dislocation spirals creates a large number of monatomic ledges, resulting in a "liquid-like" motion of solid-gas interface, which significantly deviates from the theoretically predicted sublimation plane. Our calculation based on density functional theory demonstrated that the remarkable change of sublimation rate with dislocation density is due to the dramatic reduction in binding energy of the monatomic ledges. This study provides direct observation to improve our understanding on this fundamental phase transition as well as to shed light on tuning materials' sublimation by "engineering" dislocation density in applications.

4.
Nat Commun ; 4: 1776, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23653188

RESUMO

Developments in semiconductor technology are propelling the dimensions of devices down to 10 nm, but facing great challenges in manufacture at the sub-10 nm scale. Nanotechnology can fabricate nanoribbons from two-dimensional atomic crystals, such as graphene, with widths below the 10 nm threshold, but their geometries and properties have been hard to control at this scale. Here we find that robust ultrafine molybdenum-sulfide ribbons with a uniform width of 0.35 nm can be widely formed between holes created in a MoS2 sheet under electron irradiation. In situ high-resolution transmission electron microscope characterization, combined with first-principles calculations, identifies the sub-1 nm ribbon as a Mo5S4 crystal derived from MoS2, through a spontaneous phase transition. Further first-principles investigations show that the Mo5S4 ribbon has a band gap of 0.77 eV, a Young's modulus of 300GPa and can demonstrate 9% tensile strain before fracture. The results show a novel top-down route for controllable fabrication of functional building blocks for sub-nanometre electronics.

5.
Chem Commun (Camb) ; (29): 3414-6, 2008 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-18633507

RESUMO

With the assistance of PVP, a novel magnetically recyclable Ag-based catalyst has been synthesized in one pot, and it is found that this catalyst is highly efficient in selectively catalyzing styrene conversion to styrene oxide.

6.
Chem Commun (Camb) ; (40): 4131-3, 2007 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-17925952

RESUMO

Size-dependent 3D superlattices have been fabricated from ZnO nanocrystals capped with ionic liquid components; on the basis of X-ray diffraction, two packing modes, that is, hexagonal and face-centered cubic close packings, have been discovered for the superlattices consisting of the ZnO nanocrystals as building blocks.

7.
Chemistry ; 13(31): 8754-61, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17676576

RESUMO

Highly monodisperse submicrometer CdS colloidal spheres (CSCS) with a controllable and tunable size (between 80 and 500 nm) have been synthesized through a facile solvothermal technique. Owing to the controllability of the reaction process, the growth mechanism of the colloidal spheres has been elucidated in detail. The whole growth process can be summarized as homogenous and slow nucleation of nanocrystals, formation of "cores" through 3D-oriented attachment of nanocrystals, and further surface-induced growth to monodisperse colloidal spheres through in situ formation and random attachment of additional nanocrystals. It has been demonstrated that the obtained CSCS colloidal particles are able to be assembled into films which show characteristic stop band gaps of photonic crystals. By using the CSCS as a template, Ag2S, Bi2S3, Cu2S, HgS, and Sb2S3 colloidal spheres, which are difficult to obtain directly, have also been prepared successfully through ion exchange.


Assuntos
Compostos de Cádmio/química , Compostos de Cádmio/síntese química , Sulfetos/química , Sulfetos/síntese química , Coloides , Microscopia Eletrônica de Varredura , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Espectrofotometria Ultravioleta , Propriedades de Superfície
8.
World J Gastroenterol ; 9(7): 1394-7, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12854128

RESUMO

AIM: To characterize cytochrome P4501A1 (CYP1A1), glutathione S-transferases (GSTs) and microsomal epoxide hydrolase (mEH) polymorphisms in Chinese esophageal cancer patients. METHODS: Multiplex polymerase chain reaction (PCR) and PCR based restriction fragment length polymorphisms (PCR-RFLP) were used to detect polymorphism changes of CYP, GSTs and mEH on esophageal cancerous and precancerous lesions as well as in case control group. All the examination samples were obtained from Linzhou (formerly Linxian), Henan Province, the highest incidence area for esophageal cancer. RESULTS: The frequency of CYP1A1 3' polymorphism in case control group (26/38, 68 %) was significantly higher than in esophageal squamous cell carcinoma group (ESCC) (29/62, 47 %) (P<0.05). A significant difference in the incidence of mEH slow allele variant was observed between case control group (15/38, 39 %) and esophageal dysplasia group (22/32, 69 %) or ESCC group (39/62, 63 %) (P<0.05). However, no significant difference was observed among different groups in the polymorphisms of CYP1A1 exon 7, GSTM1, GSTT1, GSTP1 and mEH fast allele. CONCLUSION: The present results suggest that CYP1A1 3' polymorphism may be one of the promising protective factors and its wild gene type may be an indicator for higher susceptibility to esophageal cancer. mEH slow allele variant, associated with the progression of esophageal precancerous lesions, may contribute to the high susceptibility to esophageal carcinoma.


Assuntos
Carcinoma de Células Escamosas/genética , Citocromo P-450 CYP1A1/genética , Epóxido Hidrolases/genética , Neoplasias Esofágicas/genética , Glutationa Transferase/genética , Idoso , Carcinoma de Células Escamosas/epidemiologia , Estudos de Casos e Controles , China/epidemiologia , Neoplasias Esofágicas/epidemiologia , Feminino , Predisposição Genética para Doença/epidemiologia , Genótipo , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição
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