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1.
Zhonghua Yi Xue Za Zhi ; 103(9): 696-699, 2023 Mar 07.
Artigo em Chinês | MEDLINE | ID: mdl-36858371

RESUMO

In order to evaluate the efficacy of resecting extramedullary subdural tumors, located in the thoracic spinal canal, via the muscle-pedicle open-door laminoplasty approach, clinical data of fifteen patients with thoracic spinal tumors admitted to the Department of Spinal Surgery in the Affiliated Hospital of Qingdao University from December 2018 to June 2021 were analyzed retrospectively. All patients received surgical treatment to remove the tumors via the muscle-pedicle open-door laminoplasty approach. The clinical data of the patient was recorded. The Japanese Orthopedic Association (JOA) score, the thoracic kyphosis angle in the standing position before and after the operation, and the visual analog score (VAS) of thoracic back incision pain before and after the operation were compared. CT scan was performed three months after the surgery and at the last follow-up to measure the healing of the lamina. In addition, MRI was used to detect the healing of the posterior ligament at the last follow-up. The tumors of all fifteen patients were completely removed, the operating time was (91±15) minutes, blood loss was (117±56) ml. Cerebral spinal fluid leakage occurred in three patients, but the incisions healed smoothly following compression and no complication was observed. All patients were followed-ups for more than 6 months. The VAS score of thoracic back incision pain was (3±1.3) points at three days post operation and it dropped to (1.3±0.9) points three months post-operation. The JOA score improved significantly after the operation, it was (11.9±2.4) points before operation, and it was (14.0±1.6) points three months post operation and increased to (16.1±0.7) points at the last follow-up (both P<0.001). The Cobb angle was 10.1°±5.3° before the operation and it was 10.4°±6.2° at the last follow-up (P=0.420). Three months after operation, partial callus formation or even complete healing on the muscle pedicle side was observed on the CT scans of all patients. At the last follow-up, CT scans showed complete healing on the muscle pedicle side. There were different degrees of sclerosis and healing on the open-door side. There was no necrosis, displacement, or secondary spinal canal stenosis in any vertebral lamina. It indicated that the muscle-pedicle open-door laminoplasty approach is an effective way to resection extramedullary subdural tumors located in the thoracic spinal canal.


Assuntos
Laminoplastia , Neoplasias da Coluna Vertebral , Humanos , Estudos Retrospectivos , Músculos , Resultado do Tratamento , Canal Medular , Dor
3.
Artigo em Chinês | MEDLINE | ID: mdl-34218554

RESUMO

Objective: This study aims to explore whether lead exposure could cause anxiety of zebrafish larvae, and to explore its mechanism. Methods: In May 2020, zebrafish embryos 4 hours after fertilization (4 hpf) were collected, E3 culture medium was used as the control group, and different lead exposure concentrations (6, 12, 24, 48 µmol/L) as the poisoned group during the time was 140 h. The mortalities, hatching rates and deformity rates were calculated, the behavioral changes of 144 hpf larvae were observed (moving speed, moving distance, activity, absolute turn angle, the light-evoked startle response, darkness-evoked escape response and thigmotaxis) . The levels of reactive oxygen species (ROS) and malondialdehyde (MDA) were detected in zebrafish larvae in the heads. ELISA kits were used to detect the expression of 5-hydroxytryptamine (5-HT) , dopamine (DA) , noradrenaline (NA) and corticotropin-releasing hormone (CRH) related to anxiety. Results: The mortalities rates of zebrafish embryos in the lead exposure concentration of 12, 24 and 48 µmol/L were higher than the control group, and the embryo hatching rates were lower than control group. The deformity rates of zebrafish larvae in the lead exposure concentration of 24 and 48 µmol/L were higher than control group (P<0.01) . The movement speed, activity and thigmotaxis of zebrafish larvae in the lead exposure concentration of 24 and 48 µmol/L were significantly lower than control group, the absolute turn angle were higher than control group (P<0.01) . The moving distance and darkness-evoked escape response of zebrafish larvae in the lead exposure concentration of 48 µmol/L group were lower than control group (P<0.05) . The light-evoked startle response of zebrafish larvae in the lead exposure concentration of 12, 24 and 48 µmol/L groups were lower than control group (P<0.05) . The ROS levels and MDA concentrations in the heads of larvae in the lead exposure concentration of 24 and 48 µmol/L were higher than control group (P<0.05) . The levels of NA and DA in the heads of the larvae in the lead exposure groups of 12, 24 and 48 µmol/L were lower than control group, and the levels of 5-HT and CRH in the heads of the larvae in the lead exposure groups of 24 and 48 µmol/L were higher than control group (P<0.05) . Conclusion: Lead exposure is toxic to zebrafish embryonic development and may cause anxiety-like neurobehavior changes and oxidative stress in zebrafish.


Assuntos
Chumbo , Peixe-Zebra , Animais , Ansiedade , Larva , Estresse Oxidativo
4.
Zhonghua Xin Xue Guan Bing Za Zhi ; 48(4): 329-335, 2020 Apr 24.
Artigo em Chinês | MEDLINE | ID: mdl-32370485

RESUMO

Objective: To investigate if microRNA (miR) -23a knockdown could attenuate angiotensin Ⅱ(AngⅡ) induced cardiac hypertrophy by activating phosphatase and tensin homolog deleted on chromosome ten(PTEN) and AMP-activated protein kinase(AMPK) pathway. Methods: Rat H9c2 cells were cultured in DMEM high glucose medium and put in 5% CO(2) incubator at 37 ℃(normal group). After 48 hours of culture, H9c2 cells were stimulated with 10 nmol/L AngⅡ to establish cell hypertrophy model (AngⅡgroup). The H9c2 cells were inoculated in a 6-well cell culture plate and cultured in an incubator at 37 ℃. When the confluence degree of cell growth was about 70%, the cells were transfected with different reagents, and 24 hours after transfection, 10 nmol/L AngⅡ was used to interfere with the cells. The H9c2 cells were divided into different groups according to the reagents, namely AngⅡ+anti-miR group(transfected with miR-23a inhibitor), Ang Ⅱ+NC group(transfected with miR-23a inhibitor negative control), Ang Ⅱ+anti-miR+si-PTEN group(cotransfected with miR-23a inhibitor and PTEN small interference RNA(siRNA)), and AngⅡ+anti-miR+si-NC group(cotransfected with miR-23a inhibitor and PTEN siRNA negative control). The surface area of single cell was measured by Image J software.The mRNA expression levels of α-actin 1 (ACTA1) and ß-myosin heavy chain (ß-MHC) and miR-23a were detected by quantitative real-time PCR(qRT-PCR). The expression levels of PTEN and AMPK signal pathway related proteins were detected by Western blot. In order to verify whether miR-23a targets PTEN gene, double luciferase reporter gene experiment was performed. The luciferase reporter gene vector recombinant plasmids of wild type pGL-WT-PTEN and mutant pGL-MUT-PTEN were constructed and prepared after normal sequencing. H9c2 cells was inoculated into 24-well cell culture plate and cultured overnight in 37 ℃ incubator. The cells were co-transfected with miR-23a mimic or miR-23a mimic negative control and wild type or mutant reporter gene recombinant plasmid. Forty-eight hours after transfection, firefly luciferase activity and sea kidney luciferase activity were measured, and the ratio of them was recorded as relative luciferase activity. Results: Compared with the normal group, the cell surface area, the mRNA expression levels of ACTA1, ß-MHC and miR-23a were significantly higher, while the protein expression levels of PTEN and p-AMPK were significantly lower in the Ang Ⅱ group(all P<0.05). The results of double luciferase reporter gene assay showed that the relative luciferase activity of cells co-transfected with miR-23a mimic and wild-type reporter gene recombinant plasmid was lower than that of miR-23a mimic negative control (P<0.05), and PTEN served as the target gene of miR-23a. In AngⅡ+anti-miR group the mRNA expression levels of miR-23a, ACTA1 and ß-MHC were lower, and the cell surface area was smaller, while the protein expression levels of PTEN and p-AMPK were higher than that in AngⅡ group and AngⅡ+NC group(all P<0.05). Compared with AngⅡ+anti-miR group, the cell surface area was bigger, the expression of ACTA1 and ß-MHC mRNA was up-regulated, and the protein expression levels of PTEN and p-AMPK were down-regulated in Ang Ⅱ+anti-miR+si-PTEN group(all P<0.05). Conclusion: Inhibition of miR-23a can attenuate Ang Ⅱ-induced hypertrophy in H9c2 cells through targeting PTEN and activating AMPK signaling pathway.


Assuntos
MicroRNAs/genética , Proteínas Quinases Ativadas por AMP , Angiotensina II , Animais , Cardiomegalia , Linhagem Celular , Proliferação de Células , PTEN Fosfo-Hidrolase , Ratos , Transdução de Sinais
5.
Zhonghua Yi Xue Za Zhi ; 99(38): 3000-3004, 2019 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-31607032

RESUMO

Objective: To evaluate the efficacy and safety of resection of lumbar nerve sheath tumors via muscle-pedicle open-door laminoplasty approach. Methods: From March 2016 to June 2018, 6 patients (4 males and 2 females, average age (45±14) years) with lumbar spinal nerve sheath tumors received surgical treatment via muscle-pedicleopen-door laminoplasty approach in the Department of Spinal Surgery, the Affiliated Hospital of Qingdao University. The operation time, blood loss, cerebral spinal fluid (CSF) leakage, and pre- and post-operative Oswestry Disability Index (ODI) and low back and leg pain visual analogue scale (VAS) were recorded for all patients. Cobb angle of lumbar lordosis was measured on the standing lateral X-ray before and 6 months after surgery. Bone fusion was observed in computed tomography at six months after surgery. Results: Total tumor resection was achieved in all the 6 patients. The operation time was from 76 to 117 minutes (average, (102±15) minutes). The blood loss was from 160 to 280 ml (average, (256±24) ml). No CSF leakage was observed in this cohort.All patients were followed up for more than 6 months. ODI and VAS for low back and leg pain were much better at one month after operation than those before the operation(t=7.70, 8.63,11.31, all P<0.05). The Cobb angle of lumbar lordosis before operation and at six months after the operation were comparable in all six patients(t=0.70, P>0.05). Bone fusion was observed in computed tomography at six months after surgery. No bone necrosis or absorption, no lamina dislodgement or spinal stenosis was occurred. Conclusions: The muscle-pedicle open-door laminoplasty approach is proved effective and safe to incise nerve sheath tumors in the lumbar spine. Some blood supply of lamina can be kept intact to accelerate bone fusion.


Assuntos
Laminoplastia , Neoplasias de Bainha Neural , Fusão Vertebral , Adulto , Feminino , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Neoplasias de Bainha Neural/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
6.
Int J Surg Case Rep ; 64: 113-119, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31630086

RESUMO

INTRODUCTION AND PRESENTATION OF CASE: Liposarcomas are rare causes of oesophageal tumours, accounting for <1% of tumours. We present a case of a dedifferentiated oesophageal liposarcoma arising from a giant fibrovascular polyp for which resection was performed via a left cervical oesophagostomy with transgastric retrieval of tumour. We also review the existing literature focusing on discussion of resection techniques. DISCUSSION: To date, 62 cases of oesophageal liposarcoma have been reported in the literature. They usually occur in males (74.2%), with a median age of 66 years (range 38-84 years). Such tumours present most commonly with dysphagia (69.4%); usually arise from the cervical oesophagus (79%), and are well-differentiated. Treatment options include surgery and recently, endoscopic resection techniques such as submucosal dissection (ESD). CONCLUSION: Giant oesophageal liposarcomas are very rare tumours. Such tumours are usually polypoid, arising from a pedicle. As such, resection techniques have shifted away from oesophagectomy to less invasive means such as endoscopic resection or oesophagostomy. Decision on type of resection technique depends on tumour characteristics and location; with the guiding principle being resection with clear margins in order to prevent local recurrence.

7.
Zhonghua Zhong Liu Za Zhi ; 41(2): 129-134, 2019 Feb 23.
Artigo em Chinês | MEDLINE | ID: mdl-30862143

RESUMO

Objective: To evaluate the short-term outcomes and safety of submucosal tunneling endoscopic resection (STER) for submucosal tumors (SMT) originating from muscularis propria (MP) layer at esophagogastric junction. Methods: The clinical data of 31 patients with SMT originating from MP layer at esophagogastric junction underwent STER were collected and retrospectively analyzed. Results: The success rate of STER of the thirty-one patients was 100%. The mean tumor size was (2.5±1.3) cm and the average operative time was (95.9±56.7) min. Perforation occurred in 3 patients and was successfully clipped by endo-clips during operation. One patient developed delayed bleeding and the bleeding was stopped by endoscopic hemostasis. Twenty-nine leiomyomas and two stromal tumors (GIST) were finally pathologically diagnosed. No local recurrence and distant metastasis were noted during the mean 15.4 months follow-up of 20 cases. According to the lesion size, 31 patients who received STER were divided into two groups. The operation time of maximum diameter ≥3.5 cm group was (134.0±70.6) min, significantly longer than (80.3±42.6) min of maximum diameter <3.5 cm group (P=0.014). However, the en bloc removal rate, postoperative hospital stay and the complication incidence between the two groups had no obvious differences (P>0.05). Univariate analysis showed that the piecemeal removal group had longer tumor diameter, higher incidence of irregular tumor morphology, and longer operative time than the en bloc removal group (all P<0.05). Stepwise logistic regression analysis showed that irregular shape was a risk factor for failure of en bloc removal (OR=18.000, 95% CI: 1.885~171.88, P=0.012). Conclusion: As a new method of minimally invasive treatment, STER technology appears to be a safe and effective option for patients with SMT originating from MP layer at esophagogastric junction.


Assuntos
Neoplasias Esofágicas/cirurgia , Junção Esofagogástrica/cirurgia , Esofagoscopia , Recidiva Local de Neoplasia , Neoplasias Gástricas/cirurgia , Análise de Variância , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/patologia , Mucosa Gástrica/patologia , Mucosa Gástrica/cirurgia , Gastroscopia , Humanos , Duração da Cirurgia , Hemorragia Pós-Operatória/etiologia , Hemorragia Pós-Operatória/terapia , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Resultado do Tratamento , Carga Tumoral
8.
Zhonghua Wai Ke Za Zhi ; 55(9): 678-683, 2017 Sep 01.
Artigo em Chinês | MEDLINE | ID: mdl-28870053

RESUMO

Objective: To discuss the clinical application and effects of domestic external fixator in the treatment of patients with malformations of limbs. Methods: A total of 7 289 patients with malformation of limbs who had been operated in Qin Sihe orthopedic surgery team from January 1989 to June 2016 were retrospective analyzed. The patients were treated with domestic external fixator, including 4 033 males and 3 256 females, aging from 2 to 82 years with a mean age of 23.4 years. There were 2 732 patients using Ilizarov external fixator, 4 713 patients using hybrid external fixator, 57 patients using monobrachial external fixator, 232 patients using Ilizarov external fixator and hybrid external fixator. The Ilizarov, hybrid and monobrachial external fixator were used in 67, 65 and 0 patients on the upper limbs and in 2 665, 4 616 and 57 patients on the lower limbs. There were 3 028 patients operated on the left limbs, 3 260 patients operated on the right limbs and 1 001 patients operated on the bilateral limbs. The top three types of diseases were sequelae of poliomyelitis, cerebral palsy and post-traumatic stress disorder peromely. Deformity types inclued talipes equinovarus, knee flexion deformity, cavus foot and so on. Results: All the patients were followed up for a period of 2.5 months to 22.4 years, with an average follow-up time of 5.4 years. All of the external fixators were used for single once, and there was no substitute for external fixator quality problem. All the patients were completed surgery goal until removing external fixation except 1 patient gave up treatment and 1 removed the fixator because of metal allergy. The common complications included wire or pin infection and joint movement limitation and so on. Conclusions: The domestic external fixator developed and produced based on the characteristics of Chinese limb deformity disability. The domestic external fixator can be used to treat kinds of limb deformities with the advantages of practical, economical, adjustable, universal and portable. The domestic external fixator could meet the clinical demand for fixation of the osteotomy end of the limbs, the correction of the deformity, the repair of the defects and the limb lengthening.


Assuntos
Fixadores Externos , Extremidades/cirurgia , Técnica de Ilizarov , Deformidades Congênitas dos Membros/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Técnica de Ilizarov/instrumentação , Deformidades Congênitas dos Membros/etiologia , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos/efeitos adversos , Procedimentos Ortopédicos/instrumentação , Osteotomia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
9.
Oral Dis ; 21(5): 602-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25677983

RESUMO

OBJECTIVES: The main aims of this study were to (i) investigate the emotional disorder status of patients with burning mouth syndrome (BMS) and (ii) detect regional cerebral blood flow in BMS patients with the application of combined single-photon emission computed tomography and computed tomography (SPECT/CT). SUBJECTS AND METHODS: The degree of pain was measured using the visual analysis scale, and emotional disorder with the self-rating anxiety scale, self-rating depression scale, and Hamilton depression rating scale in 29 patients with BMS and 10 healthy controls. SPECT/CT was performed in 29 patients with BMS and 10 healthy controls, and statistical parametric mapping method was used for between-group analyses. RESULTS: The incidence rate of depression in patients with BMS was 31.0%. Compared to the control group, patients with BMS displayed significantly different depression and anxiety scales (P < 0.05). Significantly lower regional cerebral blood flow in the left parietal and left temporal lobes was recorded for BMS patients with depression (P < 0.05). CONCLUSIONS: Patients with BMS experience more depression and anxious emotion. Moreover, depression in patients with BMS may be associated with lower regional cerebral blood flow in the left temporal and left parietal lobes.


Assuntos
Síndrome da Ardência Bucal/fisiopatologia , Síndrome da Ardência Bucal/psicologia , Circulação Cerebrovascular/fisiologia , Depressão/fisiopatologia , Depressão/psicologia , Adulto , Idoso , Ansiedade/diagnóstico por imagem , Ansiedade/fisiopatologia , Ansiedade/psicologia , Síndrome da Ardência Bucal/diagnóstico por imagem , Doença Crônica , Depressão/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/diagnóstico por imagem , Dor/fisiopatologia , Dor/psicologia , Medição da Dor , Tomografia Computadorizada de Emissão de Fóton Único/métodos
10.
J Hazard Mater ; 265: 261-70, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24394620

RESUMO

A novel method of degrading imidazolium-based ionic liquids (ILs) in wastewater using plasma electrolysis (PE) was proposed. The advantage of the PE method was that the ILs acted as both pollutant and electrolyte in the system. Results indicated that ILs with initial concentrations of 1.0-4.0g/100mL readily decomposed under an applied voltage of 600V within 120min. The anion and alkyl chain lengths of the ILs, discharge time, and post-treatment time were also found to be significant, and the degradation could be described by pseudo-first-order kinetics. Moreover, the energy efficiency of PE for degradation was calculated. The energy yield was generally higher than 2.0g/kWh, which is approximately 100 times that of the degradation of methyl orange. The oxygen atom, hydroxyl radicals, and hydrogen peroxide produced by PE were important in the oxidation and cleavage of the ILs, and the degradation pathway of the imidazolium-based ILs was investigated using IC, FT-IR, NMR, and GC-MS techniques.


Assuntos
Imidazóis/química , Líquidos Iônicos/química , Poluentes Químicos da Água/química , Eletrólise , Soluções , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química
11.
Appl Biochem Biotechnol ; 166(8): 2030-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22434354

RESUMO

To investigate the effects of selenium and light wavelengths on the growth of liquid-cultured Cordyceps militaris and the main active components' accumulation, culture conditions as selenium selenite concentrations and light of different wavelengths were studied. The results are: adenosine accumulation proved to be significantly selenium dependent (R(2) = 0.9403) and cordycepin contents were determined to be not significantly selenium dependent (R(2) = 0.3845) but significantly enhanced by selenium except for 20 ppm; there were significant differences in cordycepin contents, adenosine contents, and mycelium growth caused by light wavelengths: cordycepin, blue light > pink light > daylight, darkness, red light; adenosine, red light > pink light, darkness, daylight, blue light; and mycelium growth, red light > pink light, darkness, daylight > blue light. In conclusion, light wavelength had a significant influence on production of mycelia, adenosine, and cordycepin, so lightening wavelength should be changed according to target products in the liquid culture of C. militaris.


Assuntos
Cordyceps/crescimento & desenvolvimento , Luz , Selênio/farmacologia , Adenosina/metabolismo , Cordyceps/efeitos dos fármacos , Cordyceps/metabolismo , Cordyceps/efeitos da radiação , Técnicas de Cultura , Desoxiadenosinas/metabolismo , Relação Dose-Resposta a Droga , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Micélio/efeitos da radiação
12.
Nanotechnology ; 22(43): 435501, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-21971305

RESUMO

A vacuum pressure sensor was fabricated by assembling ZnO nanobelt film on the interdigital electrodes, and the current­voltage characteristics were measured with an Agilent semiconductor parameter tester. Under different pressures of 1.0 × 10(3), 6.7 × 10(−3), 8.2 × 10(−4) and 9.5 × 10(−5) mbar, the currents are 8.71, 28.1, 46.1 and 89.6 nA, and the pressure sensitive resistances are 1150, 356, 217 and 112 MΩ, respectively. In the range of 10(−5)­10(3) mbar the smaller the pressure is, the higher the current is. The pressure sensitive resistance of the vacuum pressure sensor increases linearly with the logarithmic pressure, and the measurement range is at least one order of magnitude wider than that of the previous sensors. Under the final pressure, the vacuum pressure sensor has maximum sensitivity (9.29) and power consumption of 0.9 µW. The sensitivity is larger than that of the previous sensor based on a ZnO single nanowire at that pressure, and the power consumption is much lower than that for the sensor based on a ZnO nanowire array. The pressure sensitive mechanism is reasonably explained by using oxygen chemisorption and energy band theory.

13.
Eur Phys J E Soft Matter ; 34(5): 54, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21626346

RESUMO

Sand particles blown by wind cause serious environmental problems and many researchers are trying to understand the dynamic properties of blown sand better. But the existing numerical approaches have not been able to simulate many important characteristics of wind-sand flow. In this paper, the evolution and fluctuation properties of blown sand at a dynamic steady state are investigated by using a more effective method. Using the LES (large eddy simulation) method for air phase movement and the DEM (discrete element method) for solid phase movement along with the existing particle-bed splashing function, we have characterized the whole movement property of the wind-sand system. The results indicate that the saturation time decreases with the inlet friction velocity, and it gradually reaches the shortest saturation time of about 1s; the saturation length, which is about 14 m at the usual wind velocity, first increases with wind velocity and then reaches a plateau; within the saturation length, the sand transport rate at different positions varies with time; the sand transport rate of the stable wind-sand flow is non-uniform with distance downwind and time, and has a notable correlation with the inflow friction velocity.


Assuntos
Monitoramento Ambiental , Poluição Ambiental , Dióxido de Silício/química , Vento , Movimentos do Ar , Fricção , Modelos Teóricos , Tamanho da Partícula
14.
Nanotechnology ; 21(5): 055708, 2010 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-20032558

RESUMO

Zn(1-x)V(x)O (x = 0.015, 0.02, 0.025, 0.03, V-ZnO) nanofibers were synthesized by electrospinning, and a butterfly-shaped piezoelectric response was measured by scanning force microscopy. The diameters of V-ZnO nanofibers with hexagonal wurtzite phase are in the range of 50-300 nm. The large piezoelectric coefficient d(33) of 121 pm V(-1) was obtained and the high piezoelectric property may be attributed to the switchable spontaneous polarization induced by V dopants and the easier rotation of V-O bonds under an electric field. The result shows that the V-ZnO nanofiber is a promising candidate for nanoscale piezoelectric devices.

15.
J Electromyogr Kinesiol ; 19(4): 639-50, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18490177

RESUMO

This study was to investigate the motor functional recovery process in chronic stroke during robot-assisted wrist training. Fifteen subjects with chronic upper extremity paresis after stroke attended a 20-session wrist tracking training using an interactive rehabilitation robot. Electromyographic (EMG) parameters, i.e., EMG activation levels of four muscles: biceps brachii (BIC), triceps brachii (TRI, lateral head), flexor carpiradialis (FCR), and extensor carpiradialis (ECR) and their co-contraction indexes (CI) were used to monitor the neuromuscular changes during the training course. The EMG activation levels of the FCR (11.1% of decrease from the initial), BIC (17.1% of decrease from the initial), and ECR (29.4% of decrease from the initial) muscles decreased significantly during the training (P<0.05). Such decrease was associated with decreased Modified Ashworth Scores for both the wrist and elbow joints (P<0.05). Significant decrease (P<0.05) was also found in CIs of muscle pairs, BIC&TRI (21% of decrease from the initial), FCR&BIC (11.3% of decrease from the initial), ECR&BIC (49.3% of decrease from the initial). The decreased CIs related to the BIC muscle were mainly caused by the reduction in the BIC EMG activation level, suggesting a better isolation of the wrist movements from the elbow motions. The decreased CI of ECR& FCR in the later training sessions (P<0.05) was due to the reduced co-contraction phase of the antagonist muscle pair in the tracking tasks. Significant improvements (P<0.05) were also found in motor outcomes related to the shoulder/elbow and wrist/hand scores assessed by the Fugl-Meyer assessment before and after the training. According to the evolution of the EMG parameters along the training course, further motor improvements could be obtained by providing more training sessions, since the decreases of the EMG parameters did not reach a steady state before the end of the training. The results in this study provided an objective and quantitative EMG measure to describe the motor recovery process during poststroke robot-assisted wrist for the further understanding on the neuromuscular mechanism associated with the recovery.


Assuntos
Terapia Passiva Contínua de Movimento/métodos , Músculo Esquelético/fisiopatologia , Paresia/fisiopatologia , Paresia/reabilitação , Robótica/métodos , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/fisiopatologia , Articulação do Punho/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Muscular , Paresia/etiologia , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/complicações , Terapia Assistida por Computador/métodos , Resultado do Tratamento
16.
Eur Phys J E Soft Matter ; 19(2): 129-38, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16491314

RESUMO

In a wind-blown sand layer, it has been found that wind transport of particles is always associated with separation of electric charge. This electrification in turn produces some electrostatic forces in addition to the gravitational and fluid friction forces that affect the movement of saltating sand particles, further, the wind-blown sand saltation. To evaluate this effect quantitatively, this paper presents a simulation of evolution of wind-blown sand grains after the electrostatic forces exerted on the grains are taken into account in the wind feedback mechanism of wind-blown saltation. That is, the coupling interaction between the wind flow and the saltating sand particles is employed in the simulation to the non-stationary wind and sand flows when considering fluid drag, gravitation, and a kind of electrostatic force generated from a distribution of electric field changing with time in the evolution process of the sand saltation. On the basis of the proposed simulation model, a numerical program is given to perform the simulation of this dynamic process and some characteristic quantities, e.g., duration of the system to reach the steady state, and curves of the saltating grain number, grain transport rate, mass-flux profile, and wind profile varying with time during the non-stationary evolution are displayed. The obtained numerical results exhibit that the electrostatic force is closely related to the average charge-to-mass ratio of sand particles and has obvious influence on these characteristic quantities. The obtained results also show that the duration of the system to reach the steady state, the sand transport rate and the mass flux profile coincide well with experimental results by Shao and Raupach (1992) when the average charge-to-mass ratio of sand particles is 60 microC/kg for the sand particles with average diameter of 0.25 mm. When the average charge-to-mass ratios of sand particles are taken as some other certain values, the calculation results still show that the mass flux profiles are well in agreement with the experimental data by Rasmussen and Mikkelsen (1998) for another category of sand particles, which tell us that the electrostatic force is one of main factors that have to be considered in the research of mechanism of wind-blown sand saltation.

17.
Environ Technol ; 26(10): 1073-80, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16342531

RESUMO

In this study, batch experiments were conducted to investigate the inhibitory effects of NaCl on H2 production from glucose by anaerobic mixed cultures. Experimental results demonstrate that NaCl concentration had significant inhibitory effects on glucose degradation, cumulative H2 production, specific H2 production rate, H2 yield and the distribution of aqueous products. The specific H2 production rate had a negative correlation with NaCl concentrations. The NaCl concentrations, at which the specific H2 production rate and H2 yield were reduced by 50%, were estimated as 209 mM and 443 mM, respectively.


Assuntos
Bactérias Anaeróbias/metabolismo , Reatores Biológicos , Fermentação/efeitos dos fármacos , Glucose/metabolismo , Hidrogênio/metabolismo , Esgotos/microbiologia , Cloreto de Sódio/toxicidade , China , Cromatografia Gasosa , Modelos Estatísticos
18.
Eur Phys J E Soft Matter ; 13(3): 321-4, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15103525

RESUMO

The craters formed by the impact of steel balls with a loose sand bed are experimentally studied. Both crater size and morphology depend strongly on the impact angle. Two scaling laws, corresponding to length and width, respectively, are proposed.

19.
Water Sci Technol ; 48(4): 69-75, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14531424

RESUMO

Continuous experiments were conducted to study the hydrolysis and acidogenesis of sewage sludge in an upflow reactor with an agitator and a gas-liquid-solid separator. Results of this study showed that 34-78% of volatile suspended solids (VSS) in sewage sludge was hydrolyzed at pH in the range 4.0-6.5, 35 degrees C and 4-24 hours of hydraulic retention time (HRT). About 31-65% of carbohydrate in sewage sludge, 20-45% of protein and 14-24% of lipid were acidified in this reactor. Hydrogen production was favored in lower pH and HRT, whereas methane production was encouraged at higher pH and HRT. Acetate, propionate, butyrate, and i-butyrate were the main aqueous acidogenic products. The distribution of these compounds in the effluent was more sensitive to pH, but was less sensitive to HRT. The maximu specific COD solubilization rate and specific volatile fatty acids production rate were 126 mg-COD/g-VSS x d and 102 mg-VFAIg-VSS x d, respectively. Compared with a CSTR, this modified upflow reactor was shown to be a more promising biosystem for the hydrolysis and acidogenesis of sewage sludge.


Assuntos
Bactérias Anaeróbias/fisiologia , Reatores Biológicos , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Ácidos Graxos Voláteis/análise , Ácidos Graxos Voláteis/química , Concentração de Íons de Hidrogênio , Hidrólise , Oxigênio/análise , Oxigênio/química
20.
Chin Med J (Engl) ; 106(9): 659-64, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8287699

RESUMO

The changes in 15 cases of viral myocarditis and 28 cases of dilated cardiomyopathy were reported and compared, which were the pathological changes of endomyocardial biopsy; NK cells activity; % of peripheral T lymphocytes and its subsets determined by using OKT3,4,8 (OKT3-peripheral total lymphocytes; OKT4-helper cells; OKT8-suppressive cells) monoclonal antibody; values of immunoglobulin IgG, IgA, IgM; titer of coxsackie B antibody neutralization test. And a discussion on their relationship was included.


Assuntos
Cardiomiopatia Dilatada/imunologia , Cardiomiopatia Dilatada/patologia , Infecções por Coxsackievirus , Enterovirus Humano B , Miocardite/imunologia , Miocardite/patologia , Adolescente , Adulto , Anticorpos Antivirais/análise , Enterovirus Humano B/imunologia , Feminino , Humanos , Células Matadoras Naturais/imunologia , Masculino , Pessoa de Meia-Idade , Miocardite/microbiologia , Miocárdio/ultraestrutura , Subpopulações de Linfócitos T/imunologia
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