Wearing transfemoral prosthesis is the only way to complete daily physical activity for amputees. Motion pattern recognition is important for the control of prosthesis, especially in the recognizing swing phase and stance phase. In this paper, it is reported that surface electromyography (sEMG) signal is used in swing and stance phase recognition. sEMG signal of related muscles was sampled by Infiniti of a Canadian company. The sEMG signal was then filtered by weighted filtering window and analyzed by height permitted window. The starting time of stance phase and swing phase is determined through analyzing special muscles. The sEMG signal of rectus femoris was used in stance phase recognition and sEMG signal of tibialis anterior is used in swing phase recognition. In a certain tolerating range, the double windows theory, including weighted filtering window and height permitted window, can reach a high accuracy rate. Through experiments, the real walking consciousness of the people was reflected by sEMG signal of related muscles. Using related muscles to recognize swing and stance phase is reachable. The theory used in this paper is useful for analyzing sEMG signal and actual prosthesis control.
Objective To discuss the technical keypoints of the second-phase diaplasis treatment after Hartmann operation. Methods Twenty-one cases of the second-phase diaplasis operation of Hartmann operation in this hospital from January 2003 to December 2007 were analysed retrospectively. Results In this group, stapler technique was used in 15 cases, anastomotic ring was used in 3 cases, and one-layer suture was used in 3 cases. The time of these operations was between 118 min and 240 min (mean 164 min). Neither stomal leak nor stomal stenosis occurred, acute ileus occurred in 2 cases, and both recovered after the treatments of gastrointestinal decompression, inhibition of secretion digestive juice and reoperation. Acute retension of urine occurred in 1 case after urine catheter removed. The symptoms disappeared after excises of bladder function. These cases were followed up for 3-36 months (mean 20 months). All the patients recovered to normal function of defecation. Conclusion The technical keypoints of the second-phase diaplasis treatment after Hartmann operation are how to find and liberate the end of the distal colon. It will affect the prognosis and the occurrence of complications after this operation.
To better use the phase information to compensate the influence of blood flow, the phase unwrapping problem in susceptibility weighted imaging (SWI) is studied in this paper. In order to improve the accuracy of unwrapping, this paper proposes a magnitude image-guided phase unwrapping algorithm of SWI. The basic idea is as follows: (1) reduce the influence of noise by improving the rotational invariant non-local principal component analysis method (PRI-NL-PCA); (2) extract the corresponding solid region in the phase image to avoid the influence of the background noise on the phase unwrapping method; (3) use the phase compensation method to constrain the phase image reconstructed by the K-space. Finally, the reliability of the unwrapping method is evaluated by using four kinds of statistics as quantification index: the number, mean (M), variance (Var), and positive percentage (Pos) and negative percentage (Neg) of phasic error points. By comparing the simulated data with 226 sets of true head SWI data, the results show that the proposed algorithm has high accuracy compared with the classical branch cut method and the least squares method.
Objective To study the relation between changes of the hepatic energy metabolism and allograft viability in early phase after orthotopic liver transplantation, arterial blood ketone body ratio (AKBR) was measured in pre- intra and post-operative phase. Methods The monkeys were divided into two groups in accordance with survived times. A group (＞24h), 5 monkeys survived 29—168 postoperative hours; B group (＜24h), 9 monkeys survived only 5—22 hours. Results AKBR in all models immediately decreased to extraordinarily low state in anhepatic-phase (versus preanhepatic phase, Ｐ＜0.01), and A group recovered rapidly to the normal levels, and maintained continuously for 12 postoperative hours above the level of 0.7. In contrast in B group, AKBR decreased below 0.7 rapidly and failed to restore to the normal level. Within 12 hours postoperatively, in B group, AKBR was lower than 0.4. Conclusion AKBR is a sensitve indicator to the allograft viability in the early phase after hepatic transplantation.
This study was aimed to improve the sensitivity of magnetic induction phase shift detection system for cerebral hemorrhage. In the study, a cerebral hemorrhage model with 13 rabbits was established by injection of autologous blood and the cerebral hemorrhage was detected by utilizing magnetic induction phase shift spectroscopy (MIPSS) detection method under the feature band. Sixty five groups of phase shift spectroscopy data were obtained. According to the characteristics of cerebral hemorrhage phase shift spectroscopy under the feature band, an effective method, B-F distribution, to diagnose the severity of cerebral hemorrhage was designed. The results showed that using MIPSS detection method under feature band, the phase shift obviously growed with increase of injection volume of autologous blood, and the phase shift induced by a 3-mL injection reached-7.750 3°±1.420 4°. B-F distribution could effectively diagnose the severity of cerebral hemorrhage. It can be concluded that the sensitivity of the cerebral hemorrhage magnetic induction detection system is improved by one order of magnitude with the MIPSS detection method under the feature band.
The cognitive impairment of type 2 diabetes patients caused by long-term metabolic disorders has been the current focus of attention. In order to find the related electroencephalogram (EEG) characteristics to the mild cognitive impairment (MCI) of diabetes patients, this study analyses the EEG synchronization with the method of multi-channel synchronization analysis--S estimator based on phase synchronization. The results showed that the S estimator values in each frequency band of diabetes patients with MCI were almost lower than that of control group. Especially, the S estimator values decreased significantly in the delta and alpha band, which indicated the EEG synchronization decrease. The MoCA scores and S value had a significant positive correlation in alpha band.
Deep brain stimulation (DBS), which usually utilizes high frequency stimulation (HFS) of electrical pulses, is effective for treating many brain disorders in clinic. Studying the dynamic response of downstream neurons to HFS and its time relationship with stimulus pulses can reveal important mechanisms of DBS and advance the development of new stimulation modes (e.g., closed-loop DBS). To exhibit the dynamic neuronal firing and its relationship with stimuli, we designed a two-dimensional raster plot to visualize neuronal activity during HFS (especially in the initial stage of HFS). Additionally, the influence of plot resolution on the visualization effect was investigated. The method was then validated by investigating the neuronal responses to the axonal HFS in the hippocampal CA1 region of rats. Results show that the new design of raster plot is able to illustrate the dynamics of indexes (such as phase-locked relationship and latency) of single unit activity (i.e., spikes) during periodic pulse stimulations. Furthermore, the plots can intuitively show changes of neuronal firing from the baseline before stimulation to the onset dynamics during stimulation, as well as other information including the silent period of spikes immediately following the end of HFS. In addition, by adjusting resolution, the raster plot can be adapted to a large range of firing rates for clear illustration of neuronal activity. The new raster plot can illustrate more information with a clearer image than a regular raster plot, and thereby provides a useful tool for studying neuronal behaviors during high-frequency stimulations in brain.
ObjectiveTo investigate the current status of symptom burden and psychological distress among lung cancer patients in the diagnostic phase, and to explore the chain mediating role of social support and resilience between symptom burden and psychological distress. MethodsThe patients with lung cancer in the diagnostic phase who were treated in the Department of Thoracic Surgery of the Second Xiangya Hospital of Central South University from October 2022 to June 2023 were investigated by a general information questionnaire using the MD Anderson Symptom Inventory, the Social Support Rating Scale, the Connor-Davidson Resilience Scale, and the Distress Thermometer. The chain mediating role of social support and resilience between symptom burden and psychological distress was analyzed. ResultsA total of 413 lung cancer patients were enrolled, including 173 males and 240 females, aged (54.69±10.82) years. The detection rate of psychological distress among lung cancer patients in the diagnostic phase was 48.18%, and the average score was (3.84±2.50) points. Psychological distress was positively correlated with symptom burden (P<0.01), and negatively correlated with social support and resilience (P<0.01). The mediating effect of resilience between symptom burden and psychological distress was significant. The chain mediating effect of social support and resilience between symptom burden and psychological distress was also significant. ConclusionLung cancer patients in the diagnostic phase have a high detection rate of psychological distress. Symptom burden can directly impact psychological distress, and can affect psychological distress through the indirect path of resilience as well as the chain mediating path between social support and resilience among lung cancer patients in the diagnostic phase.
ObjectiveTo investigate the significance of 99Tcm-MIBI SPECT dual-phase imaging, B-ultrasound and CT in the diagnosis of primary hyperparathyroidism, and its relationship with the level of serum calcium (CA). MethodsThe clinical data of 73 patients with parathyroid dysfunction (serum parathyroid hormone (PTH) > 130 pg/mL) were retrospectively analyzed. The 99Tcm-MIBI SPECT double phase imaging were performed in 73 cases, 63 cases underwent cervical B-ultrasound examination, and 16 cases underwent CT examination. According to the serum calcium (CA) levels, the patients were divided into CA < 2.7 mmol/L group and CA > 2.7 mmol/L group, and the postoperative pathological examination and followed-up results were as the standard, the sensitivity, specificity, positive predictive value, and negative predictive value of 99Tcm-MIBI SPECT dual-phase imaging, B-ultrasound and CT for diagnosis of PHPT in different serum CA levels were compared. ResultsThe sensitivity of 99Tcm-MIBI SPECT dual-phase imaging, B-ultrasound and CT examination for diagnosis of PHPT was 87.6%, 81.8% and 35.7%, respectively; the specificity was 87.5%, 75.5% and 50.0%, respectively; the positive predictive value was 98.2%, 93.7% and 83.3%, respectively; and the negative predictive value was 46.7%, 33.3% and 10%, respectively. The sensitivity, specificity, positive predictive value and negative predictive value of 99Tcm-MIBI SPECT dual-phase imaging and B-ultrasound examination for diagnosis of PHPT were significantly higher than those of CT examination(P < 0.05). The sensitivity, specificity, positive predictive value and negative predictive value of 99Tcm-MIBI SPECT dual-phase imaging for diagnosis of PHPT were higher than those of B-ultrasound examination, but the difference was not statistically significant (P > 0.05). In the CA < 2.7 mmol/L group, the sensitivity of 99Tcm-MIBI SPECT dual-phase imaging, B-ultrasound and CT examination for diagnosis of PHPT was 91.1%, 84.7% and 37.9%, respectively; the specificity was 80.2%, 72.9% and 49.7%, respectively; the positive predictive value was 96.8%, 96.0% and 79.4%, respectively; and the negative predictive value was 50.0%, 37.5% and 10.0%. In the CA > 2.7 mmol/L group, The sensitivity of 99Tcm-MIBI SPECT dual-phase imaging, B-ultrasound and CT examination for diagnosis of PHPT was 87.9%, 83.9% and 42.8%, respectively; the specificity was 83.3%, 79.2% and 50.0%, respectively; the positive predictive value was 96.9%, 94.1% and 75.0%, respectively; and the negative predictive value was 50.0%, 40.5% and 20.0%. There were no significant difference in the diagnostic accuracy between the 3 methods and the level of serum CV in different levels. ConclusionsThe diagnostic accuracy of 99Tcm-MIBI SPECT dual-phase imaging and B-ultrasound examination for diagnosis of PHPT patients with PTH > 130 pg/mL (especially parathyroid adenoma) were higher than that of CT examination, and it is not associated with the serum CA concentration.
Abstract A new type of artificial material could possibly be produced by combination of osteoblast with bioactive material in culture, and thus, make the material "alive" . To study the behavior of osteoblast cultured with bioactive materials, the osteoblasts were isolated from the periosteum of Newzeland Rabbits tibia, and cultured in RPMI1640 medium. After 13 subcultures, the cells were identified as osteoblast in vitro by electron microscope, AKP activity and detection of mineral deposition ability. The osteoblasts were subcultured with three bioactive materials: bioactive glass ceramics (BGC), hydroxyapatite (HA), and double phase hydroxyapatite (HA/TCP). After incubationfor 48 hours, scan electron microscope, 3H-TDR, XRD, RS and EDXAwere performed. The results showed that the osteoblasts grew on the HA/TCR had a higher proliferation rate and better osteoblastoid shape than those grew on BCG and HA. Themechanism of the growth of osteoblasts on bioactive materials was discussed, and the factors influencing the growth of osteoblast were analyzed.