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1.
Zhonghua Wai Ke Za Zhi ; 58(5): 350-355, 2020 May 01.
Artigo em Chinês | MEDLINE | ID: mdl-32393001

RESUMO

Objective: To examine the overall status of the Jiangsu Province Coronary Artery Bypass Grafting Registry database. Methods: The patients date of Jiangsu Province Coronary Artery Bypass Grafting Registry database from October 2017 to December 2019 was collected retrospectively.Risk factors, history, cardiac function (New York Heart Association class), extent of coronary artery lesion, European system for cardiac operative risk evaluation Ⅱ (EuroSCORE Ⅱ), cardiopulmonary bypss, arterial grafts, the numbers and flow of grafts and postoperative major adverse cardiac and cerebrovascular event(MACCE) information were analyzed. The clinical data of patients underwent on-pump CABG(ONCABG) or off-pump CABG (OPCAB) were compared by t test or χ(2) test. Results: Up till December 2019, the database enrolled 7 138 patients, in which 4 661 patients receiving primary isolated CABG. There were 3 486 males and 1 175 females with the age of (64.6±8.1) years (range:31 to 87 years). There were coronary left main disease in 960 patients, triple vessel disease in 3 934 patients, both left main and triple vessel disease in 837 patients, ejection fraction>50% in 3 841 patients, cardiac function class Ⅲ to Ⅳ in 1 664 patients. EuroSCORE Ⅱ was (2.3±0.7)% (range: 0.5% to 35.8%). There were 2 731 patients (58.59%) underwent ONCABG and 1 930 patients (41.41%) underwent OPCAB. There were 4 144 patients (88.91%) for whom the left internal thoracic artery was harvested. Seven centers (2 centers routinely) used left radial artery, 5 centers (3 centers routinely) used the transit time flow meter. The graft was 3.4±0.7 (range:1 to 7), the aortic crossclamp time was (65.0±20.4) minutes (range: 21 to 196 minutes), the cardiopulmonary bypass time was (90.0±24.2) minutes (range: 33 to 227 minutes). In-hospital death ocurred in 84 patients(1.80%), while re-operation in 93 patients (2.00%), myocardial infarction in 71 patients (1.52%), cerebral infarction in 33 patients (0.71%) and dialysis in 56 patients (1.20%). There were 2 936 patients prescribed with secondary prevention drugs(62.99%).Comparing with OPCAB group, ONCABG group had younger age, more female, more diabetes mellitus, more history of myocardial infarction and percutaneous transluminal coronary angioplasty, poorer cardiac function and coronary lesions, higher EuroSCORE Ⅱ, preoperatively (all P<0.05), and was associated with higher MACCE (135/2 731 vs. 71/1 930, χ(2)=4.280, P=0.039), and of more grafts, transfusion and intra-aortic balloon counterpulsation application (all P<0.05). Conclusions: Jiangsu Province Coronary Artery Bypass Grafting Registry database is generally in good operation, and some parameters still need to be improved. Comparing with OPCAB group, ONCABG has more severe preoperative general conditions, while the outcomes is acceptable.


Assuntos
Ponte de Artéria Coronária/métodos , Doença da Artéria Coronariana/cirurgia , Sistema de Registros , Idoso , China , Ponte de Artéria Coronária/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
2.
Zhonghua Yi Xue Za Zhi ; 96(18): 1430-4, 2016 May 17.
Artigo em Chinês | MEDLINE | ID: mdl-27266351

RESUMO

OBJECTIVE: To evaluate the effectiveness of the hybrid graft technique for complicated infrarenal abdominal aortic aneurysms (AAAs). METHODS: The clinical data of 183 patients who underwent endovascular aneurysm repair (EVAR) for AAA with challenging anatomy at Zhongshan Hospital Affiliated to Shanghai Fudan University from 2010 to 2015 were retrospectively analyzed. Endografts were divided into two groups: Hybrid Group (28 cases) used more than one type of stent graft, and Standard Group (110 cases) used only one stent graft type. Patients were recommended to undergo CT angiography at 1, 3, 6, 12 month after the procedure. Clinical data were analyzed with a focus on postoperative hospital stay, endoleak, limb occlusion, complications of approach, complications of system, converted to open operation and secondary intervention. RESULTS: Technical success was achieved in all patients in both groups. Compared with hybrid group and standard group, there was no difference in postoperative hospital stay ((5.35±2.99) and (5.92±3.70) days, t=0.753, P>0.05). During the follow up, there was no difference in endoleak (10.7% and 18.2%), limb graft occlusion (3.6% and 10.9%), complications of approach (0 and 1.8%), complications of system (7.1% and 0.9%), converted to open operation (0 and 0.9%) between two groups (χ(2)=0.896, 1.408, 0.517, 4.078, 0.256, all P>0.05). However, there was statistically significant difference in secondary intervention between two groups (3.6% and 19.1%, 2=4.011, P<0.05). CONCLUSION: The use of hybrid stent graft in patients with unfavorable neck and iliac artery anatomy AAA is feasible, and it could improve the postoperative outcomes such as secondary intervention rate.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular , Prótese Vascular , Procedimentos Endovasculares , Aorta Abdominal/cirurgia , Endoleak , Humanos , Artéria Ilíaca/patologia , Tempo de Internação , Estudos Retrospectivos , Stents , Resultado do Tratamento
3.
Eur Rev Med Pharmacol Sci ; 18(21): 3174-82, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25487925

RESUMO

OBJECTIVE: Current studies reported that patients with hemodialysis duration for three years or more were prone to infection than those with less than three years. This meta-analysis was to assess the prevalence rate and explore the risk factors of hepatitis C virus (HCV) infection among hemodialysis patients in Asia population. MATERIALS AND METHODS: Embase and PubMed databases were retrieved in 16 September, 2013 for cross-sectional studies, retrospective cohort studies or prospective cohort study about the prevalence of HCV infection of hemodialysis patients in Asian region. The prevalence rate and 95% confidence interval (CI) were used for pooled analysis. RESULTS: The combined effect of overall HCV prevalence rate in hemodialysis patients of Asian countries was 0.31 (95% CI: 0.24-0.38). Subgroup analysis showed that the prevalence rate among men was 0.28 (95% CI: 0.20-0.35), while the prevalence rate among women was 0.23 (95% CI: 0.17-0.30). Male were more vulnerable to be infected than female population (RR = 1.24, 95% CI: 1.08-1.42). Blood transfusion elevated the risk of HCV infection (RR = 0.82, 95% CI: 0.70-0.95). Short-term hemodialysis population had lower risk of infection than those who receiving the long-term hemodialysis (RR = 0.55, 95% CI: 0.34-0.91). CONCLUSIONS: The overall HCV prevalence rate of hemodialysis patients in Asian region remained at a high level of 31%, which might be increased by long-term hemodialysis and blood transfusion than people without hemodialysis. More attention and effective preventive measures are necessary.


Assuntos
Hepatite C/epidemiologia , Diálise Renal/estatística & dados numéricos , Ásia/epidemiologia , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
4.
Phys Rev Lett ; 109(12): 125504, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-23005959

RESUMO

Noble-transition metal (noble=Pt,Au; transition=Co,Ni,Cu) alloy particles with sizes of about 5 nm have been studied by in situ high-energy x-ray diffraction while subjected to oxidizing (O(2)) and reducing (H(2)) gas atmospheres at elevated temperatures. The different gas atmospheres do not affect substantially the random alloy, face-centered-cubic structure type of the particles but do affect the way the metal atoms pack together. In an O(2) atmosphere, atoms get extra separated from each other, whereas, in an H(2) atmosphere, they come closer together. The effect is substantial, amounting to 0.1 Å difference in the first neighbor atomic distances, and concurs with a dramatic change of the particle catalytic properties. It is argued that such reactive gas induced "expansion shrinking" is a common phenomenon that may be employed for the engineering of "smart" nanoparticles responding advantageously to envisaged gas environments.

5.
Nanotechnology ; 23(33): 335705, 2012 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-22863867

RESUMO

High-temperature sintering of ternary Pt(x)Ni(100-x-y)Co(y) (x = 28-44%, y = 40-54%) nanoparticles of interest in catalysis was studied in situ and in real-time with synchrotron-based x-ray diffraction. For the first time we were able to experimentally capture the early stage of the thermal treatment, and found the nanoparticles to undergo an unusual two-step coalescence process that involves transient growth and restructuring of the nanoparticles. The coalescence process is accompanied by lattice contraction, likely due to composition evolution towards a random alloy. In the late stage of sintering, evidence was found for self-limited grain growth and L1(0) chemical ordering. The order-disorder transition temperature was found to be around 800 °C in all four ternary alloy compositions studied. Fitting of the experimental data with the model for grain growth with size-dependent impediment leads to an activation energy for mass transport of about 100 kJ mol(-1), and may be used as a predictive tool to estimate particle size as a function of heat treatment temperature and duration.

6.
Nanotechnology ; 22(2): 025701, 2011 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-21135475

RESUMO

In situ real-time x-ray diffraction was used to study temperature-induced structural changes of 1-5 nm Au, Pt, and AuPt nanocatalysts supported on silicon substrates. Synchrotron-based x-ray diffraction indicates that the as-synthesized Au and Au(64)Pt(36) nanoparticles have a non-crystalline structure, while the Pt nanoparticles have the expected cubic structure. The nanoparticles undergo dramatic structural changes at temperatures as low as 120 °C. During low-temperature annealing, the Au and AuPt nanoparticles first melt and then immediately coalesce to form 4-5 nm crystalline structures. The Pt nanoparticles also aggregate but with limited intermediate melting. The detailed mechanisms of nucleation and growth, though, are quite different for the three types of nanoparticles. Most interestingly, solidification of high-density AuPt nanoparticles involves an unusual transient morphological transformation that affects only the surface of the particles. AuPt nanoparticles on silicon undergo partial phase segregation only upon annealing at extremely high temperatures (800 °C).

7.
Nanotechnology ; 20(24): 245708, 2009 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-19471088

RESUMO

In situ real-time x-ray diffraction was used to study phase segregation and coarsening of Au-Pt nanoparticles supported on silica powder, and porous alumina membranes. Contrary to the expectations from the bulk phase diagram, silica supported Au-Pt nanoparticles have an alloyed structure that is preserved even after extensive annealing at temperatures as high at 700 degrees C. In stark contrast, alumina supported Au-Pt nanoparticles exhibit a rich phase behaviour that is sensitive to alloy composition and the details of the synthesis process. In particular, low-density as-prepared Au(41)Pt(59) nanoparticles exhibit the signature of incipient phase segregation that develops into full phase separation during annealing at high temperature.


Assuntos
Coloides/química , Ouro/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Platina/química , Difração de Raios X/métodos , Sistemas Computacionais , Cristalização/métodos , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Transição de Fase , Porosidade , Propriedades de Superfície
8.
Anal Chem ; 73(18): 4441-9, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11575791

RESUMO

This paper reports the results of an investigation of vapor molecule sorption at different types of nanostructured nanoparticle films. Core-shell nanoparticles of two different core sizes, AU2-nm and Au5-nm, and molecular linkers of two different binding properties, 1,9-nonanedithiol and 11-mercaptoundecanoic acid, are utilized as building blocks for constructing chemically sensitive interfaces. The work couples measurements of two different transducers, interdigitated microelectrodes and quartz crystal microbalance, to determine the correlation of the electronic resistance change and the mass loading with vapor sorption. The responses to vapor sorption at these nanostructured interfaces are demonstrated to be dependent on the core size of nanoparticles and the chemical nature of linking molecules. The difference of molecular interactions of vapor molecules at the nanostructured interface is shown to have a significant impact on the response profile and sensitivity. For the tested vapor molecules, while there are small differences for the sorption of nonpolar and hydrophobic vapor molecules, there are striking differences for the sorption of polar and hydrophilic vapor molecules at these nanostructured interfacial materials. The implication of the findings to the delineation of design parameters for constructing core-shell nanoparticle assemblies as chemically sensitive interfacial materials is also discussed.

9.
Anal Chem ; 73(1): 103-10, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11195492

RESUMO

This paper describes the development of a prototype pumping system with the potential for incorporation into miniaturized, fluid-based analytical instruments. The approach exploits the well-established electrocapillarity phenomena at a mercury/electrolyte interface as the mechanism for pump actuation. That is, electrochemically induced changes in the surface tension of mercury result in the pistonlike movement of a mercury column confined within a capillary. We present herein theoretical and experimental assessments of pump performance. The design and construction of the pump are detailed, and the potential attributes of this design, including the generated pumping pressure, flow rate, and power consumption, are discussed. The possible miniaturization of the pump for use as a field-deployable, fluid-delivery device is also briefly examined.


Assuntos
Eletrólitos/química , Monitoramento Ambiental/instrumentação , Mercúrio/química , Eletroquímica , Desenho de Equipamento , Estudos de Avaliação como Assunto , Miniaturização , Reologia , Voo Espacial/instrumentação , Tensão Superficial , Ausência de Peso
10.
Anal Chem ; 72(10): 2190-9, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10845362

RESUMO

This paper presents findings of the creation of biomimetic ion-gating properties with core-shell nanoparticle network architectures. The architectures were formed by hydrogen-bonding linkages via an exchange-cross-linking-precipitation reaction pathway using gold nanoparticles capped with thiolate shell and alkylthiols terminated with carboxylic groups as model building blocks. Such network assemblies have open frameworks in which void space is in the form of a channel or chamber with the nanometer-sized cores defining its size, the geometric arrangement defining its shape, and the shell structures defining its chemical specificity. The formation of the network linkages via head-to-head hydrogen-bonded carboxylic terminals and the reversible pH-tuned structural properties between neutral and ionic states were characterized using infrared reflectance spectroscopic technique. The biomimetic ion-gating properties were demonstrated by measuring the pH-tuned network "open-close" responses to charged redox probes. Such redox responses were shown to depend on the degree of protonation-deprotonation of carboxylic groups at the interparticle linkages, core sizes of the nanoparticles, and charges of the redox probes. Differences in structural networking, pH-tuning, and electrochemical gating properties were identified between the network films derived from nanoparticles of two different core sizes (2 and 5 nm). The mechanistic correlation of these structural properties was discussed. These findings have added a new pathway to the current approaches to biomimetic molecular recognition via design of core-shell nanoparticle architectures at both nanocrystal and molecular scales.


Assuntos
Compostos de Alúmen/química , Ácidos Graxos/química , Ativação do Canal Iônico , Modelos Moleculares , Eletroquímica , Eletrodos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Espectrofotometria Infravermelho
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