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Objective:To investigate the effect of different scanning centers on eye lens dose, image quality, and the dose reduction rate when using the organ dose modulation (ODM) technique in head CT.Methods:The porus acusticus externus of the head phantom was considered the scanning isocenter. The ODM was initiated and the spiral scans were performed at the scanning centers with the height of porus acusticus externus and its upper and lower 2, 4, and 6 cm, respectively. The scanning range was from the top of the head to the base of the head. Three thermoluminescent dosimeters (TLD) were placed on the surface of two eyes at each scan and the average measurement value was regarded as the radiation dose to the eye lens. The volume CT dose index (CTDI vol) and dose length product (DLP) were recorded. The scans were repeated with no ODM and the dose reduction rates at each scanning center were calculated. The regions of interest (ROI) in each group of images with ODM were drawn and the noise (SD), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were evaluated. Results:Compared with the isocenter, the maximum change rates of CTDI vol and DLP in each scanning center were 2.46% and 2.43%, respectively. The eye lens dose increased as the scanning centre moving upwars (i.e. the bed dropping) by 39.02% at the position of 6 cm above the isocenter and decreased by 35.91% at the position of 6 cm below the isocenter. With the seven groups of scanning centers, the reduction rates of CTDI vol and DLP caused by ODM were 7.95%-8.61%, 7.91%-8.61% respectively, and the difference in the reduction rate of each dose value was not statistically significant( P>0.05). The reduction rate for eye lens dose ranged from 18.09% to 26.14%, with the highest reduction rate at the position of 4 cm above the isocentre and the second rate at the isocentre (24.73%). The difference in the rate of reduction at each scanning center was statistically significant( t=0.13, P<0.05). As the scanning center moved up, the SD of the eye region decreased and the SNR increased, and the highest CNR at the isocentre was 239.79. The SD and SNR of the brain parenchyma region were 6.85-7.96 and 3.08-4.19 respectively, and the highest CNR at the isocentre was 244.79. Conclusions:When ODM technique is used in head CT, the scan centre has a significant effect on the eye lens dose and image quality. Meanwhile, the reduction rate of the eye lens dose caused by ODM is also affected. Therefore, porus acusticus externus is recommended as the scanning center in head CT.
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During the traumatic brain injury (TBI), improved expression of circulatory miR-21 serves as a diagnostic feature. Low levels of exosome-miR-21 in the brain can effectively improve neuroinflammation and blood-brain barrier (BBB) permeability, reduce nerve apoptosis, restore neural function and ameliorate TBI. We evaluated the role of macrophage derived exosomes-miR-21 (M-Exos-miR-21) in disrupting BBB, deteriorating TBI, and Rg1 interventions. IL-1
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Objective:To investigate anye effect of magnetic stimulation of the sacral nerve (SMS) on acontractile detrusor disorder.Methods:Thirty spinal cord injury patients with neurogenic bladder dysfunction were randomly divided into a stimulation group and a sham group, each of 15. In a first experiment the stimulation group was treated with SMS (over S3) with a bladder volume of 100ml on the 1st day, 200ml on the 2nd day, and 300ml on the 3rd day. Each SMS session involved a total of 1500 pulses at 15Hz in 10-second bursts with 30-second intervals. For the sham group the treatment was ostensibly identical, but the coil was rotated 90 degrees. Maximum detrusor pressure was assessed before and immediately after each SMS session. In a second experiment the bladder volumes were adjusted to 200-300ml ultrasonically before treatment. Both groups were treated twice a day, 5 days a week for 4 weeks. Maximum detrusor pressures were detected at the bladder volumes of 0ml, 100ml, 200ml and 300ml before and after the 4 weeks of treatment.Results:The stimulation group′s average pressures at 200ml and 300ml had increased significantly immediately after SMS and were then significantly higher than the sham group′s averages. After 4 weeks of treatment the stimulation group′s maximum pressures were significantly higher than before treatment at all of the bladder volumes tested, and were significantly better than those of the sham group.Conclusions:SMS can significantly improve detrusor functioning, but the effect is related to bladder volume.
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BACKGROUND: Blood flow restriction training, as an emerging training method, can effectively increase muscle cross-sectional area and improve muscular function, providing a new way for sports intervention of dyskinesia. However, there are many controversies in the field from mechanism to application. OBJECTIVE: To explore the current research hotspots and main contents in the application of blood flow restriction training, and to provide new ideas and directions for future research and development in this field. METHODS: A total of 441 articles regarding blood flow restriction training published from 2009 to 2019 were retrieved from the Web of Science Core Collection database for a visual analysis using CiteSpace 5.6.R3. Based on key literatures, the analysis was performed by integration of mapping and data. RESULTS AND CONCLUSION: The research on blood flow restriction training has been on an upward trend since the 21st century, mainly published by the United States, Japan and their institutions with more achievements and higher influence. The development of the research theme has gradually changed from the impact on local tissues and organs to the impact on body functions, from the training and application in general populations to intervention therapy in special populations. Hot keywords are blood flow restriction, strength, skeletal muscle, muscle hypertrophy, growth hormone, and adaptation; its research hotspots mainly include different physiological adaptation mechanisms, training methods that influence variables, rehabilitation for people with dyskinesia, effects on cardiovascular function, etc. Low-intensity blood flow restriction training as an effective exercise intervention is mainly used in the clinical treatment and rehabilitation of musculoskeletal, cardiovascular, metabolic, and neurological diseases. Future research can focus on long-term exercise benefits, physiological adaptation mechanisms, application effects in different populations, and safety of training methods.
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Objective To investigate the effect of repetitive transcranial magnetic stimulation (rTMS) combined with the mirror therapy (MT) on the recovery of upper limb function recovery 3 to 6 months after a stroke.Methods Forty-five male patients were randomly assigned to an MT (A) group,an rTMS+MT (B) group or an MT +rTMS group (C),each of 15.All received conventional medical treatment and stroke rehabilitation.In addition,group A received 60 min of MT daily,5 days a week for 4 weeks.Group B received 10 min of rTMS over the M1 area of the affected hemisphere followed by 50 min of MT treatment,and group C received 50 min of MT treatment followed by 10 min of rTMS.rTMS was delivered at a frequency of 10 Hz and an intensity of 90％ resting motor threshold.The latency of motor evoked potential (MEP) for the affected abductor pollicis brevis muscle and its central motor conduction time (CMCT) were observed before and after the treatment.The upper extremity portion of the Fugl-Meyer assessment (FMA) was performed along with a functional test for the hemiplegic upper extremity (FTHUE).The motricity index (MI) was also quantified.Results Average MEP latency and CMCT had decreased significantly in all three groups after the treatments.The average MEP latency of group B was significantly shorter than that of group A,and CMCT was also significantly shorter than for groups A and C.Moreover,after the intervention,all of the groups had significantly improved their average FMA,MI and FTHUE scores,with the average FMA score of group B significantly better than those of groups A and C.The average FTHUE score of group B was also significantly better than that of group A.Conclusions MT either alone or in combination with rTMS can improve cerebral motor cortex excitability and motor recovery after a stroke.Ten minute rTMS sessions followed by 50 min of MT have the best effect.
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Objective:To evaluate the occluding effect of 2 kinds of Er laser on dentinal tubules.Methods:27 dentine discs were prepared,etched with 0.5 mol/L EDTA and then divided into 3 groups(n =9).The samples in group A without treatment were used as the controls,in group B treated with Er:YAG laser irradiation and in group C treated with Er,Cr:YSGG laser irradiation.The occluding effect was examined by scanning electron microscopy (SEM).Results:Micrographs of SEMshowed obvious occluding effect in group B and C.The dentinal tubule exposure rates of group A,B and C were 33.61 0% ±7.545%,4.1 86% ±0.723% and 3.798% ± 0.843% respectively(among 3 groups,P 0.05).Conclusion:The 2 kinds of Er laser can block dentinal tu-bules.