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Objective:To design a motor impairment rehabilitation monitoring aid for the assessment of motor impairment in patients who do not have or have difficulty walking independently.Methods:An assistive device vehicle was designed, equipped with an accelerometer and a six-dimensional force sensor. The normal walking (NW) group and abnormal walking group were set up, in which the abnormal walking group included moderate abnormal walking (MA) group, moderate abnormal walking with the aid of the assistive vehicle (MA-V) group, severe abnormal walking (SA) group, and severe abnormal walking with the aid of the assistive vehicle (SA-V) group. In the MA-V group, the range of knee movement was adjusted from 0 to 30°, and in the SA group, the knee joint was completely unbending. The gait cycles, peak and mean acceleration values of the right and left legs were evaluated by accelerometers, and changes in the upper limb forces were assessed by six-dimensional force transducers.Results:For the moderate impairment group, the difference in gait cycle between the MA and MA-V groups was not statistically significant ( P>0.05), and the gait cycle in the MA-V group was slightly greater than that in the MA group. For the severe injury group, the gait cycle of the SA-V group was lower than that of the SA group, and the difference was statistically significant ( P<0.01). For all abnormal groups, the mean and peak acceleration of the left leg were greater than that of the right leg, and the difference between the peak acceleration of the left leg and that of the right leg was statistically significant ( P<0.05). In the abnormal walking pattern, the mean (absolute) value of the left hand force was greater than that of the right hand, especially in the Z-axis. The standard deviations of the combined forces on the left side for the NW, MA-V, and SA-V groups were 2.759, 8.297, and 13.118 N, respectively. The SA-V group had the highest dispersion in the force scatter plot, while the NW group had a better concentration. Conclusions:An assistive vehicle equipped with an accelerometer and a six-dimensional force sensor was designed to help physicians in the assessment and rehabilitation of motor disorders.
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Objective:To establish a motion planning method for avoiding singularities for manipulator-assisted puncture surgery navigation, and design the corresponding computer program.Methods:According to the actual operation and the need of clinicians, the puncture needle sleeve installed at the end of the UR3 robotic arm was designed, and the kinematics analysis and simulation verification of the robotic arm were performed. A calculation program for solving the movement pose when the puncture needle at the end of the robotic arm reaches the target position, and a motion planning program for avoiding singularities through small-angle rotation were programmed.Results:Six groups of joint angles were randomly selected, and the theoretical coordinates calculated by the program were compared with the actual coordinates. The result showed that the error between the theoretical value and the actual value was small, which proved the correctness of the kinematics model. In the verification experiment, 3 sets of initial poses at random were simulated, the best pose was obtained by the program. Then the pose was transmitted into the control system to control the movement of the robotic arm. The verification experiment results showed that the puncture needle can reach the target point, and the singularity can be effectively avoid by the small-angle rotation of the fixed central axis.Conclusions:The singular point avoidance method based on end posture rotation can effectively avoid the failure of initial target posture motion planning, and it has reference value for the application of manipulator in puncture surgery.
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Objective:To design a portable NO rescue device that can be used for NO inhalation therapy.Methods:The NO rescue device adopts a modular design, and the key parameters can be easily adjusted. The device uses a low-intensity, high-frequency pulse discharge method to produce NO mixed gas by ionizing dry air at atmospheric pressure, and uses Ca(OH) 2 particles to filter the NO 2 gas in the NO mixed air. Based on the NO rescue device, the effects of airflow direction, gas flow rate and input voltage on the levels of NO and NO 2 in the NO mixed gas were studied. The NO 2 filtering performance of the NO 2 removal device in the device was also studied. Results:When the air flows in from the cathode and flows out from the anode of the reaction chamber, and the flow rate and input voltage respectively were 2 L/min and 4 V, the system had a better performance. At this condition, the volume fraction of NO in the output gas is 3.25×10 -5, and NO 2/NO is about 0.05. Conclusions:The proposed NO rescue device can meet the needs of medical NO gas, and the system has stable performance, portable volume, and low cost, and has broad application prospects in the treatment of pulmonary hypertension and chronic obstructive pulmonary diseases.
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Nitric oxide is a messenger molecule in the body, which is widely distributed in various tissues of living organisms and participates in regulating the physiological activities of cells. Inhalation of low concentrations of NO can selectively relax the pulmonary blood vessels, which can achieve good results and has been applied in clinical respiratory emergency treatment such as pulmonary hypertension, neonatal hypoxic respiratory failure, acute respiratory distress syndrome (ARDS), etc. At present, in addition to the clinical use of chemical methods to produce NO gas (storage in cylinders), NO can also be generated by discharge. Among them, the pulsed arc discharge can realize the preparation of NO at any time and solve the problems of decompression and storage of conventional NO gas supply. In this paper, the clinical application of NO, discharge technology, and removal methods of nitrogen dioxide (NO2) were reviewed.
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Objective To investigate the supernatant of umbilical cord-derived mesenchymal stem cells (UCMSCs) on tumor necrosis factor-α(TNF-α) and apoptosis protein caspase-3 in diabetic rats model with skin ulcer. Methods 45 Sprague-Dawley rats were randomly divided into control group (acute wounds group), phosphate buffered saline (PBS) group and UCMSCs supernatant group. The diabetic rat model was constructed by injecting with alloxan by tail vein and feeding with high-fat diet. Diabetic skin ulcer (DSU) rat model was constructed by scratching a wound and infusing suspension of Staphylococcus aureus. In the control group, the diabetic rats (n=15) were scratched to form a wound and treated by tail vein injection of 100μl PBS. In the PBS group, DSU rats (n=15) were treated by tail vein injection of 100μl PBS, and then 100μl PBS was dropped at the ulcer site. In the UCMSCs supernatant group, freeze-dried powder of UCMSCs supernatant was dissolved in 200μl PBS, 100μl of which was injected into the tail vein of DSU rats (n=15), and other 100μl was dropped at the ulcer site. After 5 days of the treatments, the levels of serum TNF-αwere detected by radioimmunoassay method, and the expression of TNF-αand caspase-3 in the ulcer tissues of rats was detected by polymerase chain reaction and Western Blot. Results The levels of TNF-αin the PBS group [(35.9±3.7)μg/L] were significantly higher than that of the control group [(11.4±4.9)μg/L] and the UCMSCs group [(14.7±6.6)μg/L] (all P<0.05). The levels of mRNA and protein expression of TNF-αand caspase-3 in the UCMSCs group were significantly lower than those of the PBS group (all P<0.05), and have no significant differences with respect to those of the control group (all P>0.05). Conclusions UCMSCs supernatant treatments can effectively down-regulate the expression of TNF-αand caspase-3 in ulcer tissue of DSU rats, and play an anti-inflammatory and anti-apoptotic effect.
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Nitric oxide is a messenger molecule in the body, which is widely distributed in various tissues of living organisms and participates in regulating the physiological activities of cells. Inhalation of low concentrations of NO can selectively relax the pulmonary blood vessels, which can achieve good results and has been applied in clinical respiratory emergency treatment such as pulmonary hypertension, neonatal hypoxic respiratory failure, acute respiratory distress syndrome (ARDS), etc. At present, in addition to the clinical use of chemical methods to produce NO gas (storage in cylinders), NO can also be generated by discharge. Among them, the pulsed arc discharge can realize the preparation of NO at any time and solve the problems of decompression and storage of conventional NO gas supply. In this paper, the clinical application of NO, discharge technology, and removal methods of nitrogen dioxide (NO2) were reviewed.
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Objective To design a mechanical arm assisted lumbar puncture ultrasound scanning system to realize automatic scanning imaging of the lumbar vertebrae and visualize the three-dimensional reconstruction of the acquired two-dimensional ultrasound image,so as to obtain the three-dimensional image of the scanning lumbar and provide a basis for path planning and assisted puncture.Methods The main control program of the robotic arm was programmed by C language which can control the robotic arm to scan the lumbar vertebrae of the patient by a clamped ultrasound.The acquired 2D ultrasound image was reconstructed and visualized using a VTK-based 3D reconstruction visualization program.The lumbar vertebrae model reconstruction was conducted by Enovo Medical Model in water and CIRS 034 lumbar vertebral phantom,respectively,and the experimental results were compared and analyzed.Results By using the lumbar puncture ultrasound scanning system,the obtained two-dimensional ultrasound image of the lumbar spine model was clear and the anatomy was basically complete.The results of three-dimensional reconstruction showed that the spinous processes and their gaps of the scanned lumbar model were clearly visible,and the structure was intact,indicating that the system was operating normally and could achieve the expected function.By comparing the reconstruction results of the bent-knee lateral position and prone position,it can be concluded that the body position has an important influence on the reconstruction results of the lumbar spine ultrasound image.The bent-knee lateral position should be used in the follow-up study of lumbar puncture.Conclusions A lumbar puncture ultrasound scanning system assisted by a mechanical arm was proposed.The system can effectively capture the clear ultrasound image of the model and realize the visualization of 3D reconstruction,which can provide a basis for puncture path planning and assisted puncture.
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Objective To explore the distribution and changes of the upper respiratory tract pressure in the human body under circulatory respiration conditions.Methods An oral-secondary bronchus model was established based on CT images.The pressure distribution at various parts of the model during circulatory respiration and the pressure distribution at the moment of maximum inspiration or expiration were simulated under a respiratory flow of 60 L/min.Results The pressure difference in the upper respiratory tract increased with the respiratory flow.Some positions with special structures,such as pharynx,larynx,trachea,etc.,showed pressure gradient changes,especially between edge of epiglottis to the trachea and upon the bifurcation point of tracheal.Conclusions The air flow motion,including pressure distribution and variation,is related to the anatomy morphological structure of the respiratory tract,and they interactively influence the respiration process.The flow field characteristics of pressure cyclic variation can provide basis for exploring the aerosol deposition and the occurrence and treatment of some respiratory tract diseases.
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Hyperlipidemia is one of the most important risk factors of human atherosclerosis and cardiaccerebral vascular disease.The number of hyperlipidemia in China increased year by year and showed a younger trend.The current treatments for hyperlipidemia include drug therapy,physical exercise,diet prevention,liposuction surgery and low-energy laser therapy,etc.Many researches showed that low intensity laser irradiation has a certain curative effect on hyperlipidemia.The aim of this paper is to provide a new idea and method for the future treatment of dyslipidemia by reviewing the anti-hyperlipidemia methods and mechanism of low energy laser irradiation treatment.
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<p><b>OBJECTIVE</b>To observe the effect of different time windows and interventions on skin pressure ulcers and ischemia-reperfusion (I/R) injury in rats.</p><p><b>METHODS</b>Sixty?eight SD rats were randomly divided into blank control group (n=4) and model group (n=64). The rats in the model group were randomly divided into group A (n=32) without intervention and group B (n=32) with post?conditioning. The degree of skin compression, neutrophil infiltration and serum levels of free radicals were observed in the rats after compression for 2, 4, 6, and 8 h (8 rats at each time point).</p><p><b>RESULTS</b>A significant difference was found in the severity of skin damage among the control group, group A, and group B (P=0.001), and the injury was milder in group B than in group A. Severe skin lesions occurred in 2 rats after skin compression for 6 h, as compared with 6 after compression for 8 h (P=0.043), but in none of the rats after compression for 2 or 4. Seventeen rats in group B and 15 in group A showed grade 1 neutrophil infiltration in the skin lesions, and 8 rats in group B and 10 in group A showed grade II neutrophil infiltration (P=0.002). Neutrophil infiltration was the mildest in rats with a 2?h compression, and exacerbated progressively and significantly as the compression time extended (P=0.027). With the prolongation of the intervention time, the rats in both groups A and B showed decreased SOD and increased MDA and NO levels, and overall the I/R injury was milder in 2? and 4?h compression groups than in 6? and 8?h compression groups. The level of serum SOD was significantly higher and MDA and NO levels were significantly higher in group B than in group A (P<0.05).</p><p><b>CONCLUSION</b>Ischemic post?conditioning can relieve I/R injury in acute pressure ulcer in rats. The effective time window for intervention is within 6 h of ischemia, and the effect of ischemic post-conditioning is optimal within 2 h. Ischemic post?conditioning can alleviate free radical injury and inflammation caused by I/R injury.</p>
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Objective To develop a light source system for the treatment of rectal cancer photodynamic therapy based on magnetic coupling resonant wireless power supply technology.Methods The proposed system consists of the implant and the external power supply device.The implant includes a light source and a resonant receiving coil.The light source is a 650 nm LED.The light source and the receiving coil were encapsulated with transparent epoxy to benefit the implantation and biocompatibility.The external power supply device was based on the magnetic coupling resonant technology,and the frequencies of the high frequency inverter and the natural frequency of the transmitting coil and the receiving coil were set at the same resonant frequency to ensure the efficient transmission of energy.Results The power density range of the light source is 3～22 mW/cm2 in the vertical distance range of 50～ 180 mm to the plane of the transmitting coil.Conclusions In the proposed light source system,the LED was separated from the power source.The size of the implant is small enough to be implanted,and the external power source can provide a real-time and stable energy supply for the implant.
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Objective To verify the effectiveness of electrical impedance tomography (EIT) with multi-layer electrodes in gastric emptying measurement by simulation experiments using EIT with three-layer electrodes.Methods Firstly,EIT system with three-layer electrodes and gastric emptying measurement simulation equipment was designed and constructed to simulate gastric emptying process and obtain EIT reconstruction images.Secondly,the region where the electrical characteristic of gastric changes was selected as region of interest.Finally,the relative impedance change rate in region of interest for every image obtained from all three layers was consecutively recorded,then the gastric emptying curve was formed and gastric emptying time was calculated.Results There are obvious differences among the sharp of impedance change curves of interested region for three layers,and the gastric emptying time and process of each layer is also different from one another.It is suggested that the passing path and emptying manner of food in gastric emptying process reflected by EIT images varied from layer to layer.Therefore,the necessity and feasibility of using EIT with three-layer electrodes in gastric emptying measurement study is verified.Conclusions EIT with three-layer electrodes can provide more abundant information of gastric motility function associated with gastric emptying pathology and physiology state.It is likely to be a noninvasive,convenient and effective imaging method for the detection and evaluation research on gastric emptying and gastric motility.
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Objective Practical electrical impedance tomography (EIT) system with certain measurement resolution (MR) and signal-to-noise ratio (SNR) differs a lot from ideal simulation conditions in EIT methodology research. The aim of this paper was to study the impact of practical system with different MR and SNR on EIT. Methods Based on the ideal simulation boundary voltages of adjacent excitation and adjacent measurement pattern, practical systems whose MR were 0.1 mV and 0.01 mV, SNR ranged from 40-80 dB and no noises were simulated, simulation study for three imaging models A, B and C with different positions in the to-be imaged field under practical system conditions above was carried out using the combined Tikhonov-NOSER regularization algorithm, and error of reconstruction (ER) function and structure similarity (SSIM) function were adopted for quantitative evaluation of image effect. Results There are differences between images obtained under different MR and SNR for different image models. In order to obtain images for three models, SNR of system should be at least 40-50 dB when MR was 0.01 mV. For the goal to obtain high quality images of A, B and C, SNR should be 80, 70 and 60 dB respectively. When MR was 0.1 mV, SNR for obtaining images of A, B, C were 60, 50 and 40 dB. Moreover, the improvement of images with increasing SNR under MR of 0.1 mV was not as obvious as that of MR at 0.01 mV. Conclusions Blind pursuit of single high SNR is of no help to improve system performance and image reconstruction effect except increasing the difficulties in hardware design. The extremity SNR is 50-60 dB for system with MR of 0.01 mV and 60-70 dB for system with MR of 0.1 mV.
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Objective To study the phase correlation of cutaneous multichannel impedance measurements and the contractions, peristalsis of stomach and the conduction properties in space.Methods A spiral gastric body model was rotated to simulate shrinkage and creep of the stomach.In order to verify the feasibility and validity of the multichannel impedance gastric dynamic measurement, experiments with emulation of multichannel impedance gastric motility measuring principle were conducted through three-dimensional simulation on the electrical characteristics of gastric body model in saline tank simulator.Results The emulation results showed that the change of epigastric current density and potential distribution is consistent with the course of moving from top to bottom when lateral edge of model (namely the intumescent location when the stomach is full) after detecting electrodes in sequence.Meanwhile, the measurement voltage wave forms clearly showed the contraction location of stomach after the model rotating for three cycles in a row, and the phase relationship between adjacent measurement channels was also measured.The sixty seconds data acquired by the experiment device proved that voltage wave form of three measurement channels corresponded to the phase relationship of movement status of the gastric body model.Conclusions Cutaneous multichannel wave forms prove a cyclical movement of stomach, and phase difference among the multichannel signals relating to speed of peristaltic wave, position of the measuring electrodes and channel spacing, etc.This study provides simulation and experimental basis for explanation of quantitative study of conduction properties in space and phase relationship between the results of surface multichannel impedance measurements and the contractions, peristalsis of stomach.
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Objective To explore the molecular targets and mechanisms that could influence the sensitivity of triple negative breast cancer (TNBC) to chemotherapy,to provide important references for the chemotherapy based on gene detection.Methods The gene expression dataset GSE43502 was downloaded from the Gene Expression Omnibus in National Center for Biotechnology Information (NCBI).Gene expression data preprocessing was conducted by R Programming.The differentially expressed genes in the TNBC patients that relapsed after chemotherapy compared with the non-relapsed ones were obtained.Besides,the Database for Annotation Visualization and Integrated analysis (DAVID) was used for functional analysis of those genes.The microRNA (miRNA) that might regulate the differentially expressed genes was obtained from the starBase database.Furthermore,Cytoscape was used for the construction of miRNA-gene regulation network.Results Three hundred and twelve differentially expressed genes were obtained.Some biological process related to cell membrane,metal ion homeostasis and pathways involved in immune and inflammatory were found to be enriched in those genes.Furthermore,171 miRNA that might regulate the differentially expressed genes were obtained and 553 miRNA-gene regulation pairs were formed.Conclusions hsa-miR-30d-5p,SIX4,etc.might influence the sensitivity of TNBC to chemotherapy through cell structure or immune system.
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Objective To acquire high spatial resolution two-dimension pulse pressure distribution for objectifying research of pulse diagnosis in traditional Chinese medicine.Methods A sensor array with flexible packing was designed and implemented.The array was formed on a circle substrate with 37 silicon piezoresistive pressure sensors,which were distributed as equilateral triangles with 1.95 mm pitch.The diameter of the substrate was 15 mm.By using flexible packing,the array had the hardness similar to that of human finger,which made this method closer to the traditional Chinese diagnosis.After differential amplifying,37-way pulse pressure signals were digitalized and reconstructed to obtain the pulse pressure distribution.Results With the application of the sensor array,the pulse pressure signals were measured and transformed into pulse pressure distribution.Conclusions The experimental result contains the relevant characteristics of traditional Chinese pulse diagnosis' description,providing a new way for objective study of traditional Chinese pulse diagnosis and further study.
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Objective To study the radioresistance increased by low level laser irradiation (LLLI) in stem cells.Methods Umbilical cord mesenchymal stem cells (UC-MSCs) were divided into control group and experimental groups (LLLI only,γ-ray irradiation only and LLLI combined with γ-ray irradiation groups).635 nm (10 mW/cm2,12 J/cm2) laser irradiation was applied using for 3 days (twice a day),and cells were exposed in 2 Gy dose γ-ray irradiation on the third day.DNA injury was detected by alkaline single cell gel electrophoresis,reactive oxygen species (ROS),superoxide dismutase (SOD) and catalase (CAT) activity were valued using detection kits.Results DNA injury in LLLI combined with γ-ray irradiation group was lower than that in γ-ray irradiation exposed group,activity of oxidation stress kinases was enhanced,and level of ROS was inhibited.Conclusions Ironizing radioresistance of UC-MSCs can be increased after treatment of 635 nm LLLI,which will induce the radiation sensitivity of transplanting cells.
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Objective To develop and test a high precision medical device which allows measurement of bioimpedance in regions below skin surface,and to enable the assessment of strained muscle's situation and instruct patient's rehabilitation exercise.Methods The system was based on the four-electrode impedance measurement mode and designed by using impedance converter network analyzer AD5933 and monolithic operational amplifier AD844.The hardware consisted of an excitation current source,a response signal adjustment circuit,a digital demodulation circuit and a shield driving circuit.This hardware circuit was combined with a LCD screen and a keyboard,which turned it into a portable precision bioimpedance testing device.Results Using an model of three components as test target,a comparison between the device and the Agilent 4294A precision impedance analyzer was presented.In the range of 1 kHz to 100 kHz,the device showed the similar relative error of the complex impedance's modulus and 1 degree absolute error of the complex impedance's phase.The strained muscle's bioelectrical impedance changes in a clinical case during the convalescent were presented and discussed with the results proven to be clinical meaningful.Conclusions The device is accurate,simple and convenient,which is proved qualified on helping doctors to assess the injury states of the strained muscle and to instruct patient's rehabilitation exercise.
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Objective To establish a new methodology of evaluating rehabilitation status of local muscle injured by measuring the impedance and phase information.Methods An evaluation method was set up,which take symmetrical parts of injured muscle as control group during the measurement.Impedance and phase values of injured muscle were extracted with local impedance measurement method before and after rehabilitation to evaluate muscle recovery.Results Injured muscle tissue impedance values decreased significantly.In the process of rehabilitation of injured muscle,the impedance and phase values of the injured muscles were gradually approaching that of healthy muscle,and then achieved basically the same as reference values after rehabilitation.Conclusions Local impedance measurement method may provide a new,non-invasive and convenient evaluation method for the recovery of injured muscle tissue,and it has good prospects for clinical application.
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BACKGROUND/AIMS: This study aimed to detect the expression of natural killer (NK) cell receptor natural killer group 2D (NKG2D) in the peripheral blood of patients with primary hepatocellular carcinoma and to discuss the correlation between NK cell cytotoxicity and liver function. METHODS: The number of NK cells and the expression of NK cell receptor NKG2D in peripheral blood were determined by flow cytometry in patients with primary hepatocellular carcinoma, hepatitis B cirrhosis, chronic hepatitis B, and healthy controls. RESULTS: When compared with patients in the healthy and the chronic hepatitis B groups, the primary hepatocellular carcinoma group showed significant decreases in all parameters, including the cytotoxicity of NK cells on K562 cells, expression rate of NKG2D in NK cells, number of NKG2D+ NK cells, expression level of NKG2D, and number of NK cells (p<0.05). The activity of NK cells showed a positive correlation, whereas the Child-Pugh scores in the primary hepatocellular carcinoma and the hepatitis B cirrhosis groups showed a negative correlation with all parameters detected above. CONCLUSIONS: The decrease of NK cell activity in patients with primary hepatocellular carcinoma is closely related to their lower expression of NKG2D. Liver function affects the expression of NKG2D and the activity of NK cells.