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1.
Opt Express ; 31(4): 6514-6528, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36823905

RESUMO

Light detection and ranging (lidar) is widely accepted as an indispensable sensor for autonomous vehicles. There are two fundamental challenges in a lidar system: optical beam steering technique and ranging method. Optical phased array (OPA) is considered as one of the most promising beam steering schemes due to its solid state, compact size, and high reliability. As for ranging method, time-of-flight and frequency-modulate continuous-wave (FMCW) are commonly utilized in numerous research. However, they are impractical to commercial OPA lidar due to either requiring excessive optical power or the poor stability, high complexity, and high insertion loss of the FMCW source. As a result, the development of OPA lidars is significantly hindered by the lack of a feasible ranging method. In this paper, we present a phase-modulated continuous-wave (PhMCW) ranging method with excellent ranging accuracy and precision. Ranging error as low as 0.1 cm and precision on the order of 3.5 cm are achieved. In addition, theoretical and experimental study on simultaneous velocity measurement is carried out and velocity error as low as 0.15 cm/s is obtained. Finally, we develop a proof-of-concept OPA-PhMCW lidar and obtain a point cloud with excellent fidelity. Our work paves a novel approach to solid-state, cost-effective and high-performance OPA lidars.

2.
Medicine (Baltimore) ; 97(29): e11520, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30024535

RESUMO

Catheter ablation has been wildly used to treat atrial fibrillation (AF) and has achieved a better efficacy for paroxysmal AF (PAF) but not for persistent AF (PerAF). Furthermore, a few data on the efficacy and safety of catheter ablation for PerAF were reported. This study aimed to investigate long-term efficacy of radiofrequency catheter ablation (RFCA) for PerAF and explore predictors of late recurrence of atrial fibrillation (LRAF).A total of 92 consecutive patients with PerAF (64 males, aged 56.42 ±â€Š11.24 years) were enrolled in this study and accepted circumferential pulmonary vein isolation (CPVI) alone or CPVI combined additional ablation.Maintenance rate of sinus rhythm (SR) was 40.2% after a single procedure with median follow-up of 15 months and 52.2% after mean 1.3 ±â€Š0.6 procedures with median follow-up of 26 months. Long-term SR maintenance rate was no statistical difference between patients with CPVI alone and with CPVI combined additional ablation (48.6% vs 35.1%, log rank test, P = .152). Patients with AF duration < 24 months had a higher long-term SR maintenance rate than those with AF duration ≥ 24 months (55.6% vs 30.4%, log rank test, P = .022). AF duration (OR = 1.015, 95%CI 1.001-1.030, P = .015), and early recurrence of AF (ERAF) (OR = 10.654, 95%CI 3.853-29.460, P < .001) were predictors of LRAF after a single procedure.In conclusion, long-term maintenance SR rate was 52.2% in patients with PerAF after multiple procedures with a median over 2-year follow-up. Patients with AF duration < 24 months had better outcome. AF duration and ERAF were predictors of LRAF after a single procedure.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Adulto , Idoso , Estudos de Casos e Controles , Ablação por Cateter/efeitos adversos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
3.
Artigo em Zh | WPRIM | ID: wpr-867657

RESUMO

Objective:To analyze the clinical characteristics of patients with different types of coronavirus disease 2019 (COVID-19).Methods:A total of 272 eligible COVID-19 patients who were admitted to Guangzhou Eighth People′s Hospital, Guangzhou Medical University from January 22 to February 15, 2020 were retrospectively enrolled. General characteristics, the first laboratory examination and imaging data of these patients were collected. According to the clinical classification, there were 236 cases in non-severe group (mild+ common type) and 36 cases in severe group (severe+ critical type). Comparisons between groups were performed by t test, chi-square test or rank-sum test when appropriate. Results:There were 23 males and 13 females in the severe group, 103 males and 133 females in the non-severe group, and the difference was statistically significant ( χ2=5.149, P=0.023). The age of severe group was (60.5±11.2) years, which was higher than that of non-severe group (46.8±15.7) years. The difference was statistically significant ( t=6.43, P<0.01). The lymphocyte (LYM) count, platelet (PLT) count and arterial partial pressure of oxygen (PaO 2) in the severe group were 0.90(0.55, 1.10)×10 9/L, 170.00(143.50, 198.00)×10 9/L and 73.50(69.70, 83.00) mmHg(1 mmHg=0.133 kPa), respectively, which were all lower than those in the non-severe group (1.42(1.09, 1.95)×10 9/L, 187.00(148.00, 230.00)×10 9/L and 96.00(83.20, 108.00) mmHg, respectively). The differences were all statistically significant ( Z=5.59, 2.00 and 5.00, respectively, all P<0.05). The levels of creatine kinase (CK), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), C reaction protein (CRP) and procalcitonin (PCT) in the severe group were 123.00(79.00, 212.00) U/L, 32.10(27.00, 47.40) U/L, 305.50(216.00, 396.00) U/L, 37.02(23.92, 63.66) mg/L and 0.09(0.05, 0.19) μg/L, respectively, which were all higher than those in the non-severe group (68.00(48.00, 103.00) U/L, 20.10(16.70, 26.20) U/L, 179.00(150.00, 222.00) U/L, 26.55(18.11, 36.96) mg/L and 0.04(0.03, 0.06) μg/L respectively), and the differences were all statistically significant ( Z=3.89, 5.60, 5.12, 2.85 and 5.43, respectively, all P<0.01). No significant differences were observed in white blood cell count, creatine kinase isoenzyme and blood lactate between the two groups ( Z=1.53, 0.41 and 1.00, respectively, all P>0.05). Conclusion:Gender, age, LYM count, PLT count, PaO 2, CK, AST, LDH, CRP and PCT could be used to provide reference for clinical classification of COVID-19 patients.

4.
Artigo em Zh | WPRIM | ID: wpr-499952

RESUMO

Objective To investigate the value of arthroscope in the diagnosis and treatment of knee synovitis. Methods 50 cases of knee synovitis diagnosed by arthroscopy and treated by endoscopic synovectomy were studied. There were 10 cases with rheumatoid arthritis, 11 cases with pigmented villonodular synovitis,5 cases with chronic infection of knee joint,12 cases with chronic non-specific synovitis,5 ca-ses with tuberculous synovitis of the knee,4 cases with meniscus injury,3 cases with unknown cause. The efficacy of the treatment was recor-ded. Results All these cases were clearly diagnosed by microscopic examination combined with synovial pathological examination,and 10 cases were corrected with clinical diagnosis post-operation. All cases received primary healing without serious complications. All cases were followed up,and 6 cases of pigmented villonodular synovitis,2 cases of rheumatoid arthritis,1 case of chronic non-specific synovitis and 1 case of tuberculous synovitis of the knee had recurred. The total effective rate was 80. 0%. Conclusion The application of arthroscopy and syno-vial biopsy was effective in diagnosis. Arthroscopic synovectomy had good effect on treatment with less trauma and complications.

5.
Artigo em Zh | WPRIM | ID: wpr-447494

RESUMO

Objective To observe the clinical effect of magnesium isoglycyrrhizinate on moderate and severe nonalcoholic steatohepatitis(NASH) and analyse its mechanism. Methods 42 cases with moderate and severe nonalcoholic steatohepatitis were selected in our study. All patients were divided into observation group and control group randomly. Control group were received simvastatin while the observation group were received simvastatin combined with magnesium isoglycyrrhizinate treatment. The course was 6 weeks.The changes of NASH classiifcation, clinical symptom, liver function, lipid levels and liver ifbrosis items in two groups before and after treatment were observed and recorded. Results All patients were received 6 week treatment, none of them dropped out. The clinical symptoms were improved in both two groups. There were 5 severe NASH improved to moderate NASH, 8 moderate NASH improved to mild NASH in observation group while only 3 severe NASH improved to moderate NASH in control group. The difference of NASH classiifcation between two groups was signiifcant(P<0.05). Compared to pre-treatment, the AST, ALT, TBIL,γ-GT were decreased in both two groups. But the liver function items in observation were lower than control group(P<0.05). The lipid level were decreased in both two group and there were no signiifcant differences between two groups after treatment. The level of PC III, HA, C-IV were decreased in observation group while had no changes in control group. Conclusion The magnesium isoglycyrrhizinate could decrease the AST, ALT and lipid level, improve the classiifcation of liver ifbrosis, and had low rate of side effect during treatment.

6.
Artigo em Zh | WPRIM | ID: wpr-385554

RESUMO

Objective To investigate the association of high-sensitivity C-reactive protein(hs-CRP) with the abnormality of glucose metabolism in patients with essential hypertension.Methods Based on the level of fast plasma glucose(FPG) and 2-hours-plasma glucose(2hPG),120 patients with essential hypertension were divided into 3 groups:Normal glucose tolerance group(NGT),impaired glucose tolerance group(IGT)and diabetes mellitus group (DM).The hs-CRP was measured.Results The level of hs-CRP gradually increased from NGT to DM groups(P<0.05).The level of hs-CRP was positively correlated with SBP,DBP,2hPG and FPG in patients with essential hypertension(r =0.48,0.37,0.46,0.31,P<0.05).Conclusion The abnormality of glucose metabolism in patients with essential hypertension was related with hs-CRP.

7.
Artigo em Zh | WPRIM | ID: wpr-578685

RESUMO

Objective:To investigate the role of AngⅡreceptors(AT1 and AT2) in the left ventricular hypertrophic process and its mechanisms through detecting the expression of AngⅡreceptors(AT1 and AT2) in hypertrophic cardiomyocyte induced by pressure overload in rats. Methods:Fourteen Male Sprague-Dawley rats were divided into two groups: sham group(n=7),and operation group(n=7). Left ventricular hypertrophy model was well established after abdominal aortic stenosis in each group.The expression of AT1 and AT2 was detected by immunohistochemistry(IHC) and RT-PCR,respectively. Indexes of left ventricular hypertrophy,including myocardial fibrosis,LVMI,cross-sectional area and apoptosis index(APOI),were also measured. Results: SBP,DBP,MBP,LVMI,and cardiomyocyte CSA,APOI,level of plasma AngⅡand expression of AT1 and AT2 in operation group were markedly increased as compared with sham group. Conclusion:Expression of cardiomyocyte AT1 and AT2 receptors were increased significantly in rat of left ventricular hypertrophy,which indicated that AT1 and AT2 receptors both participate in the process of left ventricular hypertrophy but they may play antagonism effects.

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