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find Keyword "efficiency" 31 results
  • Dynamic analysis of epileptic causal brain networks based on directional transfer function

    Epilepsy is a neurological disease with disordered brain network connectivity. It is important to analyze the brain network mechanism of epileptic seizure from the perspective of directed functional connectivity. In this paper, causal brain networks were constructed for different sub-bands of epileptic electroencephalogram (EEG) signals in interictal, preictal and ictal phases by directional transfer function method, and the information transmission pathway and dynamic change process of brain network under different conditions were analyzed. Finally, the dynamic changes of characteristic attributes of brain networks with different rhythms were analyzed. The results show that the topology of brain network changes from stochastic network to rule network during the three stage and the node connections of the whole brain network show a trend of gradual decline. The number of pathway connections between internal nodes of frontal, temporal and occipital regions increase. There are a lot of hub nodes with information outflow in the lesion region. The global efficiency in ictal stage of α, β and γ waves are significantly higher than in the interictal and the preictal stage. The clustering coefficients in preictal stage are higher than in the ictal stage and the clustering coefficients in ictal stage are higher than in the interictal stage. The clustering coefficients of frontal, temporal and parietal lobes are significantly increased. The results of this study indicate that the topological structure and characteristic properties of epileptic causal brain network can reflect the dynamic process of epileptic seizures. In the future, this study has important research value in the localization of epileptic focus and prediction of epileptic seizure.

    Release date:2023-02-24 06:14 Export PDF Favorites Scan
  • Cooperative decision-making of county-level public hospitals based on generalized fuzzy data envelopment analysis

    Objective To establish a cooperative decision-making model of county-level public hospitals, so as to freely select the best partner in different decision-making units and promote the optimal allocation of medical resources. Methods The input and output data of 10 adjacent county-level public hospitals in Henan province from 2017 to 2019 was selected. Based on the traditional data envelopment analysis (DEA) model, a generalized fuzzy DEA cooperative decision-making model with better applicability to fuzzy indicators and optional decision-making units was constructed. By inputting index information such as total number of employees, number of beds, annual outpatient and emergency volume, number of discharged patients, total income and hospital grade evaluation, the cooperation efficiency intervals of different hospitals were calculated to scientifically select the best partner in different decision-making units.Results After substituting the data of 10 county-level public hospitals in H1-H10 into the model, taking H2 hospital as an example to make cooperative decision, among the four hospitals in H1, H2, H7 and H10 of the same scale, under optimistic circumstances, the best partner of H2 hospital was H7 hospital, and the cooperation efficiency value was 1.97; in a pessimistic situation, the best partner of H2 hospital was H10 hospital, and the cooperation efficiency value was 0.98. The model had good applicability in the cooperative decision-making of county-level public hospitals. Conclusion The generalized fuzzy DEA model can better evaluate the cooperative decision-making analysis between county-level public hospitals.

    Release date:2022-02-24 02:27 Export PDF Favorites Scan
  • Hemodynamic analysis of a new retrievable vena cava filter

    Vena cava filter is a filter device designed to prevent pulmonary embolism caused by thrombus detached from lower limbs and pelvis. A new retrievable vena cava filter was designed in this study. To evaluate hemodynamic performance and thrombus capture efficiency after transplanting vena cava filter, numerical simulation of computational fluid dynamics was used to simulate hemodynamics and compare it with the commercialized Denali and Aegisy filters, and in vitro experimental test was performed to compare the thrombus capture effect. In this paper, the two-phase flow model of computational fluid dynamics software was used to analyze the outlet blood flow velocity, inlet-outlet pressure difference, wall shear stress on the wall of the filter, the area ratio of the high and low wall shear stress area and thrombus capture efficiency when the thrombus diameter was 5 mm, 10 mm, 15 mm and thrombus content was 10%, 20%, 30%, respectively. Meanwhile, the thrombus capture effects of the above three filters were also compared and evaluated by in vitro experimental data. The results showed that the Denali filter has minimal interference to blood flow after implantation, but has the worst capture effect on 5 mm small diameter thrombus; the Aegisy filter has the best effect on the trapping of thrombus with different diameters and concentrations, but the low wall shear stress area ratio is the largest; the new filter designed in this study has a good filtering and capture efficiency on small-diameter thrombus, and the area ratio of low wall shear stress which is prone to thrombosis is small. The low wall shear stress area of the Denali and Aegisy filters is relatively large, and the risk of thrombosis is high. Based on the above results, it is expected that the new vena cava filter designed in this paper can provide a reference for the design and clinical selection of new filters.

    Release date:2019-04-15 05:31 Export PDF Favorites Scan
  • The Effect of Continuous Improvement of Quality Control Mechanism on the Emergency Treatment Efficiency for Acute ST Segment Elevation Myocardial Infarction in Chest Pain Center

    ObjectiveTo explore the effect of continuous improvement of quality control system on the emergency treatment efficiency for patients with acute ST segment elevation myocardial infarction (STEMI) after the establishment of Chest Pain Center. MethodsWe retrospectively analyzed the differences of theory examination scores acquired by the Chest Pain Center staff one month before and after they got the system training. Moreover, we designated the STEMI patients treated between May and August 2015 after the establishment of Chest Pain Center but before optimization of process to group A (n=70), and patients treated from September to December 2015 after optimization of process to group B (n=55). Then we analyzed the differences between these two groups in terms of the time from patients' arriving to registration, the time from arriving to first order, the length of stay in Emergency Department, and even the time from door to balloon (D2B). ResultsThe scores acquired by Chest Pain Center staff before and after system training were 69.89±6.34 and 87.09±4.39 respectively, with a significant difference (P<0.05). All the time indicators of both group A and group B were shown as median and quartile. The time from patients' arriving to registration of group A and group B was 6.0 (0.0, 11.0) minutes and 1.0 (0.0, 3.0) minutes (P<0.05); the time from arriving to first order was 12.8 (9.0, 18.0) minutes and 5.0 (3.0, 9.0) minutes (P<0.05); the length of stay in Emergency Department was 54.0 (44.0,77.0) minutes and 33.0 (20.0, 61.0) minutes (P<0.05); and the time of D2B was 107.5 (89.0, 130.0) minutes and 79.0 (63.0, 108.0) minutes (P<0.05). ConclusionAfter taking measures such as drawing lessons from the past, training staff and optimizing process continuously, we have significantly shortened the acute STEMI patients' length of stay in the Emergency Department, which has saved more time for the following rescue of STEMI patients.

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  • Optimization of Triple Plasmids Transfection into HEK293 Cells Mediated by Polyethylenimine

    In the present study, packaging system composed of pAAV-CMV-GFP, pAAV-RC and pHelper were transfected into human embryonic kidney 293 cells (HEK293 cells) mediated by polyethyleneimine (PEI) to explore an optimal transfection condition. Different total plasmid DNA dosages (1, 2, 3, 4, 5, 6μg) and different PEI/Plasmid ratios (1:1, 3:1, 5:1, 7:1) were tested with detection of green fluorescence protein (GFP) with ImagePro Plus6.0 Software. Then transfection efficiency of the optimized transfection system was further observed for different time periods(12, 24, 36, 48, 60, 72 h). The results showed that total plasmid dosage of 4μg/well with PEI/plasmid ratio of 3:1~5:1 was an efficient transfection condition. Transfection efficiency-time curve was an S-shaped curve. Transfection efficiency reached a plateau at 60 h after transfection. The optimized conditions for PEI-mediated transfection at the optimal time result in enhanced transfection efficiency of triple plasmid into HEK293 cells.

    Release date:2021-06-24 10:16 Export PDF Favorites Scan
  • Connectivity pattern of action potentials causal network in prefrontal cortex during anxiety

    Anxiety disorder is a common emotional handicap, which seriously affects the normal life of patients and endangers their physical and mental health. The prefrontal cortex is a key brain region which is responsible for anxiety. Action potential and behavioral data of rats in the elevated plus maze (EPM) during anxiety (an innate anxiety paradigm) can be obtained simultaneously by using the in vivo and in conscious animal multi-channel microelectrode array recording technique. Based on maximum likelihood estimation (MLE), the action potential causal network was established, network connectivity strength and global efficiency were calculated, and action potential causal network connectivity pattern of the medial prefrontal cortex was quantitatively characterized. We found that the entries (44.13±6.99) and residence period (439.76±50.43) s of rats in the closed arm of the elevated plus maze were obviously higher than those in the open arm [16.50±3.25, P<0.001; (160.23±48.22) s, P<0.001], respectively. The action potential causal network connectivity strength (0.017 3±0.003 6) and the global efficiency (0.044 2±0.012 8) in the closed arm were both higher than those in the open arm (0.010 4±0.003 2, P<0.01; 0.034 8±0.011 4, P<0.001), respectively. The results suggest that the changes of action potential causal network in the medial prefrontal cortex are related to anxiety state. These data could provide support for the study of the brain network mechanism in prefrontal cortex during anxiety.

    Release date:2020-08-21 07:07 Export PDF Favorites Scan
  • Clinical research on the perioperative hemodynamic changes recorded by MostCare/PRAM system in the off-pump coronary artery bypass grafting surgery

    ObjectiveTo investigate the perioperative hemodynamic changes of off-pump coronary artery bypass grafting (OPCABG) patients monitored by pulse recorded analysis method (MostCare/PRAM devices) and its relationship with the prognosis.MethodsA total of 89 patients who underwent OPCABG from October 2016 to January 2017 in Beiijng Anzhen Hospital were included, including 53 males and 36 females aged 60.50±8.40 years. The hemodynamic changes were recorded. The patients were divided into two groups (a major adverse cardiovascular events group and a stable group) according to whether major adverse cardiovascular events occurred or not. The difference of hemodynamic changes between the two groups was analysed.ResultsThe mean percentage increases of stroke volume (SV) in the passive leg raising (PLR) test before opening chest and after chest closure were 23.00%±3.20% and 29.40%±3.70%, respectively. Hemodynamic data were analysed seven times, namely, anaesthesia, opening chest, heparin administration, coronary artery bypass grafting, protamine administration, thoracic closure and after operation. SV was significantly decreased during above periods, while systemic vascular resistance index (SVRI) was significantlyincreased. Cardiac circle efficiency (CCE) and maximum pressure gradient (dP/dT) were decreased after anaesthesia, and decreased to the lowest value during the procedure of bypass grafting, and then they began to increase gradually after the manipulation of bypass grafting was finished. Stroke volume variation (SVV) and pulse pressure variation (PPV) were slightly decreased during anaesthesia, then increased significantly through the whole surgery. Major adverse cardiovascular events occurred in 9 patients and 4 of them died. The basic mean values of SVRI, SVV and PPV of patients in the major adverse cardiovascular events group before opening chest were significantly higher than those of patients in the stable group. There was no significant difference in the mean values of CCE, dP/dT or SV between the two groups. There was no significant correlation between the prognosis and the mean values of SVRI, SVV, PPV, CCE, dP/dT or SV.ConclusionThe hemodynamic indexes are not stable, thus, it is necessary to monitor the perioperative hemodynamic changes of OPCABG patients timely by MostCare/PRAM device and adjust treatment measures accordingly.

    Release date:2021-02-22 05:33 Export PDF Favorites Scan
  • Impact of market competition on the efficiency of private hospitals

    ObjectiveTo investigate the distribution, service volume, and medical efficiency of private general hospitals in Sichuan Province to provide references for optimizing the allocation of health resources in Sichuan Province. MethodsUsing the 2020 data from private general hospitals above the second level in 18 cities and states in Sichuan Province, this study calculated the market concentration and competitiveness with the Herfindahl-Hirschman index (HHI). A three-stage data envelopment analysis (DEA) model was employed to eliminate environmental variables and random errors for hospital efficiency analysis. Influencing factors were conducted using a Tobit regression model. ResultsThe HHI indices for the number of licensed (assistant) physicians, beds, and total consultations in each city and state were below 1 000, indicating a low concentration market. The comprehensive technical efficiency, pure technical efficiency, and scale efficiency of private general hospitals above the second level in Sichuan Province were 0.534, 0.661, and 0.806, respectively, after the three-stage DEA analysis. The number of practicing (assistant) physicians was negatively correlated with scale efficiency. the number of beds was negatively correlated with pure technical efficiency. The total number of consultations showed a positive correlation with overall technical efficiency, pure technical efficiency, and scale efficiency. ConclusionThe provincial private hospital market exhibits low concentration competition. Differences in efficiency exist among various regions, grades, and hospital types. Market competition in resource allocation promotes the improvement of pure technological efficiency and scale efficiency. Market share competition hinders the improvement of comprehensive technical efficiency, pure technical efficiency, and scale efficiency.

    Release date:2023-08-14 10:51 Export PDF Favorites Scan
  • Evaluation of exercise ventilation function in patients with chronic duration of not well controlled asthma

    Objective To explore the characteristics of exercise ventilation function in patients with chronic duration of asthma, and the correlation of cardiopulmonary exercise test and control level and conventional lung function in patients with chronic duration of asthma. Methods Seventy-three patients with chronic duration of asthma admitted from December 2021 to December 2022 were recruited in the study. The asthma control level was assessed with the asthma control test (ACT) and the patients were divided into a well-controlled group and a poorly-controlled group. Routine pulmonary function test (PFT) and cardiopulmonary exercise test (CPET) were performed in both groups, to analyze the difference of related parameters between the two groups and observe the correlation between CPET and PFT, ACT score in the patients with chronic persistent asthma. Results CPET results showed that the VE/VCO2 slope, anaerobic threshold carbon dioxide equivalent (EqCO2@AT), and physiologically ineffective peak during exercise (VD/VTpeak) were higher in the poorly-controlled group than those in the well-controlled group (all P<0.05). The peak minute ventilation (VEpeak) and tidal volume (VTpeak) of the patients in the poorly-controlled group were lower than those in the well-controlled group (both P<0.05). The peak respiratory rate (BFpeak) and respiratory reserve (BRpeak) of the two groups were not significantly different (both P>0.05). The results of correlation analysis showed that the VE/VCO2 slope, EqCO2@AT, VD/VTpeak were negatively correlated with ACT score, and VEpeak was positively correlated with FVC%pred and MMEF%pred in the patients with chronic persistent asthma. BRpeak was positively correlated with FEV1%pred, FEV1/FVC%pred, MMEF%pred in routine pulmonary function. Multivariate logistic regression analysis showed that the increase of VE/VCO2 slope and VD/VTpeak were independent risk factors for poor asthma control (P<0.05). Conclusions Patients with poorly-controlled asthma have decreased exercise ventilatory function, mainly showing decreased ventilation and tidal volume during peak exercise and decreased ventilatory efficiency. There is some correlation between exercise ventilatory function and conventional lung function of control level in patients with chronic duration of asthma. The relevant indicators of ventilation efficiency in CPET have suggestive significance for asthma that is not well controlled, so it is necessary to carry out CPET in patients with asthma to improve the comprehensive evaluation of asthma.

    Release date:2024-05-16 01:48 Export PDF Favorites Scan
  • EFFECTS OF HYPERTHERMIA COMBINED WITH MITOMYCIN,5-FLUOROURACIL IN VITRO ON HUMAN GASTRIC CARCINOMA CELL

    The antitumor activity of hyperthermia combined with mitomycin(MMC),5-fluorouracil(5-Fu)was observed in human gastric carinoma cell line MGC-803.The study was aimed at understanding the percentage of living carcinoma cell,plating efficiency and survival fraction.The results showed that hyperthermia combinedwith MMC had a synergistic antitumor activity which was enhanced with temperature increasing,but it was not the same as hyperthermia combined with 5-Fu.In comparison with simple hyperthermia,the antitumor activity of hyperthermia combined with 5-Fu was enhanced at lower temperture.This results raises a basis of clinical practice.

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