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2.
Zhonghua Nei Ke Za Zhi ; 62(11): 1317-1322, 2023 Nov 01.
Artigo em Chinês | MEDLINE | ID: mdl-37935498

RESUMO

Objective: To compare the clinical outcomes of endovascular therapy in acute stroke patients with anterior circulation tandem occlusions caused by atherosclerosis or dissection. Methods: A retrospective cohort study. A total of 98 patients with anterior circulation tandem lesions undergoing endovascular therapy in the Wuhan NO.1 Hospital (March 2016 to March 2022) were analyzed. Median age was 64(55,71) years old, and 82.7% (81/98 cases) were males. According to the lesion etiology, the patients were divided into atherosclerosis and dissection groups. The differences in clinical outcomes between the two groups were investigated, including favorable 90-day functional outcome (modified Rankin Scale score of 0-2), successful reperfusion (modified Thrombolysis in Cerebrovascular Infarction score of 2b-3), symptomatic intracranial hemorrhage, stroke-associated pneumonia, 90-day all-cause mortality, and average hospitalization days. Logistic regression analysis was used to adjust for potential confounders affecting functional outcomes in both groups, and to determine odds ratios and 95% confidence intervals. Results: Seventy-one patients were grouped into the atherosclerotic cause and 27 into the dissection cause cohorts. The rate of favorable 90-day functional outcome was 43.7% (31/71 cases) in the atherosclerosis group versus 55.6% (15/27 cases) in the dissection group (adjusted odds ratio=1.339; 95% confidence interval, 0.374-4.798; P=0.654). No significant differences were found in other clinical outcomes between the two groups (all P>0.05). Conclusion: The clinical prognosis of patients with tandem lesions caused by atherosclerotic stenosis or artery dissection was similar after endovascular therapy. Future studies are still needed to verify our results.


Assuntos
Aterosclerose , Procedimentos Endovasculares , Acidente Vascular Cerebral , Masculino , Humanos , Feminino , Estudos Retrospectivos , Trombectomia/efeitos adversos , Trombectomia/métodos , Resultado do Tratamento , Procedimentos Endovasculares/métodos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Stents/efeitos adversos
3.
Osteoporos Int ; 33(1): 89-96, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34235549

RESUMO

We investigated the secular trends of the incidence and hospitalization cost of hip fracture in Tangshan, China. The incidence of hip fracture and the hospitalization cost were both increasing during the observation period. INTRODUCTION: The present study aimed to determine sex-, age-, and fracture type-specific incidence and annual changes in hip fractures in Tangshan, China, between 2007 and 2018. METHODS: We analyzed annual hip fracture incidence using urban hospital data during 2007-2018 and calculated incidence rate/100,000 person years in each age group and sex. We assessed annual changes in incidence among people aged >60 years using linear-by-linear association tests and evaluated hospitalization costs with the Kruskal-Wallis test. RESULTS: During the study period, we observed an increasing proportion of hip fractures in people >60 years old from 14.2 to 22.79%. Crude hip fracture incidence increased markedly from 140.87 to 306.56/100,000 in women (p < 0.01) and from 124.83 to 167.19/100,000 in men (p < 0.01) in the age group >60 years. Type-specific analysis indicated significantly increased trends in incidence of cervical and trochanteric fractures among women and cervical fracture among men (p < 0.01). In people aged 36-60 years, the trend of hip fracture increased significantly in both sexes. The total and cervical-to-trochanteric ratio in men increased, with significant upward trends (p < 0.01). The proportion of cervical fracture was higher than that for trochanteric fracture in women, with stable levels from 2007 to 2018. Hospitalization costs for cervical and trochanteric fractures increased by 51.91% and 53.20%, respectively, during 2011-2018. CONCLUSION: Tangshan will have an increasing burden on health care resources attributable to a considerable rise in hip fracture incidence and the older population. Further investigation of risk factors and subsequent implementation of effective measures to prevent hip fracture are needed.


Assuntos
Fraturas do Quadril , Distribuição por Idade , China/epidemiologia , Feminino , Fraturas do Quadril/epidemiologia , Hospitalização , Humanos , Incidência , Masculino , Pessoa de Meia-Idade
4.
Phys Rev E ; 103(2-1): 023208, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33736100

RESUMO

Dynamics of the transition from a linear plasma wave to a nonlinear state characterized by the Bernstein-Greene-Kruskal mode is studied within the framework of the Vlasov-Poisson system. In the linear stage, the plasma distribution function (f) develops finer and finer structures in velocity space through a series of "mixing" processes leading to the Landau damping of the plasma wave. These mixing processes inevitably result in strong phase irregularities in velocity space. Using numerical simulations, it was observed that starting from the wave-particle resonance region, this irregular phase pattern gets "smoothed out" through a process of spreading of phase synchronization, which tends to reduce Landau damping, facilitating the formation of the nonlinear plasma wave as a fully synchronized final state. It is also found that there exists a residual damping for the quasisteady nonlinear wave when the phases of the particles are not fully synchronized.

5.
Zhonghua Yi Xue Za Zhi ; 100(21): 1640-1647, 2020 Jun 02.
Artigo em Chinês | MEDLINE | ID: mdl-32486599

RESUMO

Objective: To explore the application value of mass spectrometry (MS) combined with next generation sequencing (NGS) in diagnosing neonatal inherited metabolic diseases (IMD). Methods: The clinical information, metabolites in blood and urine, and gene sequencing results of 19 neonates with IMD coming from the Department of Neonatology of Jiangxi Provincial Children's Hospital from March 2017 to September 2019 were analyzed retrospectively. The metabolites in blood were detected by liquid chromatography tandem mass spectrometry and urine were detected by gas chromatography-mass spectrometry respectively.Meanwhile, the whole bloods were dectected by neonatal genetic disease panel based on NGS. Results: Twelve neonates had the same results between MS and NGS among the 19, 2 had different results from MS to NGS, and 4 had no disease indication by MS but were diagnosed by NGS whose clinical phenotype were partially consistent with NGS results. One of them who did not carry out MS was considered as the diagnosis of IMD because of the detection of gene, and was followed up on this basis. Conclusion: MS could diagnose IMD relatively quickly to guide clinical treatment, and while NGS could verify the results of MS detection. Combination of MS and NGS would understand the cause of disease on genetic level, so as to guide further treatment and genetic consultation.


Assuntos
Doenças do Recém-Nascido , Doenças Metabólicas , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Recém-Nascido , Espectrometria de Massas , Estudos Retrospectivos
6.
Phys Rev E ; 101(3-2): 039902, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32289887

RESUMO

This corrects the article DOI: 10.1103/PhysRevE.100.033212.

7.
Phys Rev E ; 101(3-1): 030201, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32289950

RESUMO

Phase synchronization is a universal concept in macro- and microstate coupling of complex systems. In this Rapid Communication, we demonstrate the existence of phase synchronization dynamics in a wave-particle interaction process under the framework of a Vlasov-Poisson (VP) system. Starting from a random phase setup, it is shown that the phases of the electrons spontaneously develop coherent patterns in its velocity space. The most interesting finding is that, mediated by the long-wavelength electrostatic mode, the phases of the electrons tend to attract each other, condense into a mean phase, and form a chimera pattern. Due to the finite-time singularity of the mean phase, the phase pattern gets evaporated and recondenses into a different chimera pattern. For the scenario of a finite wavelength, the random phases rapidly condense to slashing lines, which become steeper and steeper through a sequence of evaporation-condensation processes. The slashing pattern drives the mixing of the distribution function in the velocity space, which then induces the damping of the electrostatic mode. This phase self-organization dynamics uncovers another aspect of wave-particle interaction physics, and sheds light onto the longstanding enigma of Landau damping.

8.
Phys Rev Lett ; 125(25): 255003, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33416359

RESUMO

We show that the radial electric field (E_{r}) plays a dual role in edge magnetohydrodynamics (MHD) activity. While E_{r} shear (first spatial derivative of E_{r}) dephases radial velocity and displacement, and so is stabilizing, a new finding here is that E_{r} curvature (second spatial derivative of E_{r}) tends to synchronize the radial velocity and displacement, and so destabilizes MHD. As a highlighted result, we analytically demonstrate that E_{r} curvature can destabilize an otherwise stable kink mode, and so form a joint vortex-kink mode. The synergetic effects of E_{r} shear and E_{r} curvature in edge MHD extend the familiar E×B shearing paradigm. This theory thus explains the experimental findings that a deeper E×B well may aggravate edge MHD, and so trigger the formation of the edge harmonic oscillation. A simple criterion linking E_{r} structure and the edge MHD activity is derived.

9.
Phys Rev E ; 100(3-1): 033212, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31640003

RESUMO

A profile-evolving simulation of the Controlled Shear Decorrelation Experiment (CSDX) linear device is performed with our newly developed code. The simulation result shows an excellent agreement with the experimental observations of profiles and fluctuations of plasma density and electric potential in the B=1000 G standard discharges, suggesting the mechanism of their evolutions. According to our simulation, an avalanche of plasma density, featuring a rapid destruction of particle profile, is triggered every time the dominant instability transits from near adiabatic collisional drift wave to non-adiabatic Kelvin-Helmholtz instability. The avalanches always start at the point where the local vorticity is the maximum among the whole device. A critical vorticity is found for any avalanche to happen. The avalanches always lead to intermittent particle and heat convective structures outside the main plasma column, and these structures are ejected out as avaloids when zonal flow intensity at birth time is weak.

10.
Phys Rev Lett ; 117(12): 125002, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27689282

RESUMO

A new, frequency modulation mechanism for zonal flow pattern formation is presented. The model predicts the probability distribution function of the flow strength as well as the evolution of the characteristic spatial scale. Magnetic toroidicity-induced global phase dynamics is shown to determine the spatial structure of the flow. A key result is the observation that global phase patterning can lead to zonal flow formation in the absence of turbulence inhomogeneity.

11.
Phys Rev Lett ; 114(14): 145002, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25910130

RESUMO

We demonstrate that E×B shear, V_{E×B}^{'}, governs the dynamics of the cross phase of the peeling-ballooning-(PB-)mode-driven heat flux, and so determines the evolution from the edge-localized (ELMy) H mode to the quiescent (Q) H mode. A physics-based scaling of the critical E×B shearing rate (V_{E×B,cr}^{'}) for accessing the QH mode is predicted. The ELMy H mode to the QH-mode evolution is shown to follow from the conversion from a phase locked state to a phase slip state. In the phase locked state, PB modes are pumped continuously, so bursts occur. In the slip state, the PB activity is a coherent oscillation. Stronger E×B shearing implies a higher phase slip frequency. This finding predicts a new state of cross phase dynamics and shows a new way to understand the physics mechanism for ELMy to the QH-mode evolution.

12.
Artigo em Inglês | MEDLINE | ID: mdl-24827182

RESUMO

We present a theory of turbulent elasticity, a property of drift-wave-zonal-flow (DW-ZF) turbulence, which follows from the time delay in the response of DWs to ZF shears. An emergent dimensionless parameter |〈v〉'|/Δωk is found to be a measure of the degree of Fickian flux-gradient relation breaking, where |〈v〉'| is the ZF shearing rate and Δωk is the turbulence decorrelation rate. For |〈v〉'|/Δωk>1, we show that the ZF evolution equation is converted from a diffusion equation, usually assumed, to a telegraph equation, i.e., the turbulent momentum transport changes from a diffusive process to wavelike propagation. This scenario corresponds to a state very close to the marginal instability of the DW-ZF system, e.g., the Dimits shift regime. The frequency of the ZF wave is ΩZF=±Î³d1/2γmodu1/2, where γd is the ZF friction coefficient and γmodu is the net ZF growth rate for the case of the Fickian flux-gradient relation. This insight provides a natural framework for understanding temporally periodic ZF structures in the Dimits shift regime and in the transition from low confined mode to high confined mode in confined plasmas.

13.
Curr Oncol ; 20(3): e180-92, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23737688

RESUMO

BACKGROUND: Our retrospective study in breast cancer patients evaluated whether integrating subtype and pathologic complete response (pcr) information into axillary lymph node restaging after neoadjuvant chemotherapy (nac) adds significance to its prognostic values. METHODS: Patients included in the analysis had stage ii or iii disease, with post-nac axillary lymph node dissection (alnd), without sentinel lymph node biopsy before completion of nac, with definitive subtyping data and subtype-oriented adjuvant treatments. The ypN grading system was used to restage axillary lymph node status, and ypN0 was adjusted by pcr in both breast and axilla into ypN0(pcr) and ypN0(non-pcr). Univariate and multivariate survival analyses were performed. RESULTS: Among the 301 patients analyzed, 145 had tumours that were hormone receptor-positive (hr+) and negative for the human epidermal growth factor receptor (her2-), 101 had tumours that were positive for her2 (her2+), and 55 had tumours that were triple-negative. The rate of pcr in both breast and axilla was 11.7%, 43.6%, and 25.5% respectively for the 3 subtypes. Compared with the non-pcr patients, the pcr patients had better disease-free survival (dfs) and overall survival (os): p = 0.002 for dfs and p = 0.011 for os. In non-pcr patients, dfs and os were similar in the ypN0(non-pcr) and ypN1 subgroups, and in the ypN2 and ypN3 subgroups. We therefore grouped the ypN grading results into ypN0(pcr) (n = 75), ypN0- 1(non-pcr) (n = 175), and ypN2-3 (n = 51). In those groups, the 3-year dfs was 98%, 91%, and 56%, and the 3-year os was 100%, 91%, and 82% respectively. The differences in dfs and os between those three subgroups were significant (all p < 0.05 in paired comparisons). Multivariate Cox regression showed that subtype and ypN staging adjusted by pcr were the only two independent factors predicting dfs. CONCLUSIONS: Axillary lymph node status after nac, adjusted for pcr in breast and axilla, predicts differential dfs in patients without prior sentinel lymph node biopsy.

14.
Nanotechnology ; 24(24): 245303, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23690027

RESUMO

A novel approach to the fabrication of metal-cell-metal trilayer memory devices was demonstrated by using only two cycles of lithography and dry-etch procedures. The fabricated ultrahigh density crossbar devices can be scaled down to ≤70 nm in half-pitch without alignment issues. Depending on the different dry-etch mechanisms in transferring high and low density nanopatterns, suitable dry-etch angles and methods are studied for the transfer of high density nanopatterns. Some novel process methods have also been developed to eliminate the sidewall and other conversion obstacles for obtaining high density of uniform metallic nanopatterns. With these methods, ultrahigh density trilayer crossbar devices (~2 × 10(10) bit cm(-2)-kilobit electronic memory), which are composed of built-in practical magnetoresistive nanocells, have been achieved. This scalable process that we have developed provides the relevant industries with a cheap means to commercially fabricate three-dimensional high density metal-cell-metal nanodevices.

15.
J Nanosci Nanotechnol ; 11(3): 2611-4, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21449437

RESUMO

For bit-patterned media, media with low remanent magnetization (M(r)) and high M(r) regions are needed for storing information, which is usually achieved by lithographically defining magnetic and non-magnetic regions. In this work, we have investigated the use of ion beam modification of media surface to define the low and high M(r) states using a medium that is at a low M(r) state to start with. The low M(r) state is achieved by the use of synthetic antiferromagnetic coupling obtained in Co-alloy/Ru/Co-alloy trilayer structured film. Local ion beam modification at 30 keV energy using Ga+ ions was used to create high M(r) regions. AFM and MFM observations indicated that patterned regions of low and high M(r) can be observed with ion beam irradiation. This technique is a potential method to achieve patterned media without the need of planarization techniques.


Assuntos
Cobre/química , Nanoestruturas/química , Rubídio/química , Cobre/efeitos da radiação , Íons , Magnetismo , Teste de Materiais , Nanoestruturas/efeitos da radiação , Rubídio/efeitos da radiação
16.
Zhongguo Yao Li Xue Bao ; 17(4): 379-82, 1996 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-9812730

RESUMO

AIM: To study the effects of oxymatrine (Oxy) on arrhythmia in dogs with myocardial infarction. METHODS: Partly ligating the left anterior descending coronary artery in the open-chest dogs produced myocardial infarction of left anterior ventricular wall. After 5-8 d, the diastolic excitability threshold (DET), the effective refractory periods (ERP) and arrhythmias were determined by programmed electric stimulation (PES). RESULTS: Oxy (i.v. 50 mg.kg-1) increased DET from 2.53 +/- 1.28 to 3.19 +/- 1.62 V, lengthened ERP from 182 +/- 25 to 219 +/- 43 ms at normal region and from 206 +/- 49 to 235 +/- 55 ms at infarct region in left ventricle, but had no effects on dispersion of ERP, QTc interval and ventricular tachycardia (VT) or ventricular fibrillation (VF). Procainamide (Pro) (i.v. 25 mg.kg-1) increased DET and lengthened ERP and QTc interval, but decreased the dispersion of ERP. Pro prevented PES-induced VT/VF and spontaneous ischemia-related VF. CONCLUSION: The increased DET and lengthened ERP of Oxy are its anti-arrhythmic mechanism.


Assuntos
Alcaloides/farmacologia , Antiarrítmicos/farmacologia , Arritmias Cardíacas/prevenção & controle , Infarto do Miocárdio/fisiopatologia , Animais , Cães , Feminino , Masculino , Quinolizinas , Período Refratário Eletrofisiológico/efeitos dos fármacos
17.
Zhongguo Yao Li Xue Bao ; 12(1): 44-7, 1991 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-1950584

RESUMO

The effects of berbamine (Ber, 10 mg.kg-1 iv) on ischemic ventricular tachyarrhythmia and electrophysiologic consequences in both normal and ischemic myocardia were studied in the open-chest dogs subjected to programmed electrical stimulation (PES) on 5-8 d after acute myocardial infarction. Its effects were compared with procainamide's (PA). Both drugs distinctly lengthened the QTc interval and the effective refractory period (ERP) of normal and infarct ventricular myocardium, decreased the dispersion of ERP in infarct myocardium (IDR) and the dispersion of ERP in left ventricle (VDR), and increased the diastolic excitability threshold (DET) of normal and infarct ventricular myocardium remarkably. The PES-induced ventricular tachycardia (VT) or ventricular fibrillation (VF) was prevented in 5 out of 6 dogs treated with berbamine and procainamide respectively. (Normal saline did not prevent PES-induced VT or VF). The results suggest that berbamine may be effective in preventing the onset of reentrant ventricular tachyarrhythmia after myocardial ischemic damage.


Assuntos
Alcaloides/farmacologia , Antiarrítmicos , Benzilisoquinolinas , Infarto do Miocárdio/fisiopatologia , Taquicardia/fisiopatologia , Alcaloides/uso terapêutico , Animais , Cães , Eletrofisiologia , Feminino , Masculino , Procainamida/farmacologia , Período Refratário Eletrofisiológico/efeitos dos fármacos , Taquicardia/prevenção & controle , Fibrilação Ventricular/prevenção & controle
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