The principle on the pitting electrochemical noise detected by using wavelet transform was described briefly and the signal of pitting electrochemical noise was analyzed for commercial pure aluminum in 3.5 % NaCl solution. The result showed that wavelet transform could not only obtain the waveform characteristic of pitting signaland system noise in the multi-scale space, but also detect the waveform of pitting electrochemical noise according to the transmitting characteristic of the maximum module of wavelet coefficients, which represented the waveform characteristic.

Objective To study the dynamic expression and distribution of high mobility group box 1 (HMGB-1)in diffuse axonal injury (DAI)in rats and to clarify its involvement in the inflammatory reaction after DAI in rats,in order to provide new targets for the clinical treatment of DAI.Methods A DAI model was established using a coronal rotation device and evaluated by HE,Glees-Marsland silver staining,and Mallory phosphotungstic acid hematoxylin staining.Immunohistochemistry,Western blot and RT-PCR were used to detect the expression and distribution of HMGB-1 in the cortex of DAI rats at 6 h,1 d,3 d and 7 d.And TUNEL was used to examine the apoptosis of neurons in DAI rats.Results Immunohistochemical results showed that at 6 h and 1 d after DAI,the number of HMGB-1-positive cells decreased,but at 3 and 7 d it began to increase.Western blot also showed that during the early stage after DAI (6 h and 1 d),the level of HMGB-1 protein in the cortex was significantly lower than that in the control group,but at the late stage (3 and 7 d)after DAI it significantly increased compared with that in the control group until 7 d.RT-PCR showed that at 6 h after DAI there was no significant increase in the level of HMGB-1mRNA,but at 1 d there was a slight increase compared with the control group;at 3 and 7 d,it showed an obvious significance.TUNEL staining indicated that the significant neuronal apoptosis appeared as early as 6 h after DAI,and reached the peak at 3 d;it started to decrease at 7 d but still remained at a relatively high level.Conclusion The dynamic expression and distribution of HMGB-1 showed significant changes with the time course after DAI in rats.They decreased at the early stage but increased at the late stage.At the early stage, HMGB-1 is mainly passively released by the necrotic neurons,and at the late stage it may be actively secreted by the active inflammatory cells.HMGB-1 may mediate the post-DAI neural cell apoptosis by inducing the inflammatory reaction.

Objective To observe the functional connectivity (FC) pattern linking the hippocampus with the rest of the brain in ischemic stroke patients with cognitive dysfunction,especially the default mode network (DMN).Methods Resting-state functional connectivity magnetic resonance imaging (fMRI) was performed on 15 ischemic stroke patients with cognitive dysfunction (the patient group) and 10 normal elderly controls.The bilateral hippocampus was the region of interest.Correlation analyses yielded a mapping of cerebral functional connectivity activation for both groups.Results Compared with the healthy controls,the patient group showed weakened functional connectivity between the hippocampus and other regions including the cingulate gyrus,the superior,middle and inferior frontal lobes,the inferior parietal lobule and the superior temporal gyrus.But there was enhanced functional connectivity with the cerebellar posterior lobe,the occipital lobe,the medial temporal lobe,the precuneus and the calcarine.The results were significantly different between the two groups.Conclusion The functional connectivity pattern of the hippocampus is impaired in stroke patients with cognitive dysfunction.Reduced functional connectivity between brain regions may be one cause of cognitive dysfunction after stroke,and enhanced functional connectivity may be an appropriate compensatory mechanism.

Objective To research the effect ofparecoxib on hippocampal nerve cell apoptosis and expressions of B cell lymphoma/lewkmia-2 (Bcl-2),Bcl-2 associated X protein (Bax) and caspase-3 of epilepsy rats.Methods Thirty SD male rats were randomly divided into three groups (n=10):control group,parecoxib treatment group and epilepsy group.The rats in the parecoxib treatment group and epilepsy group were injected with 4 mg/kg of parecoxib and same volume of saline,respectively,and 3 d after that,they both were injected intraperitoneally with 3 mmol/kg of lithium chloride,and then,20 h after that,they were injected intraperitoneally with 30 mg/kg ofhydrochloride pilocarpine; while rats in the control group were only injected intraperitoneally with the same volume of saline.The behavior changes of rats in the three groups were observed.After 7 d,terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) was used to evaluate the neuronal apoptosis and Western blotting was employed to evaluate the expressions of Bcl-2,Bax and caspase-3 in the hippocarnpus of all groups.Results All epilepsy rats were very irritable; spontaneous seizures (SRS) times of precoxib treatment group were significantly reduced as compared with those of epilepsy group (P＜0.05).As compared with those in the control group,the Bcl-2,Bax and caspase-3 expressions and Bcl-2/Bax ratio in the epilepsy group were increased with statistically significant differences (P＜0.05); As compared with those in the epilepsy group,the Bcl-2,Bax and caspase-3 expressions and Bcl-2/Bax ratio in the precoxib treatment group were decreased with statistically significant differences (P＜0.05).As compared with that in the control group,the number of TUNEL positive cells in hippocampus of rats in the precoxib treatment group and epilepsy group were significantly increased (P＜0.05); as compared with that in the epilepsy group,the number of TUNEL positive cells in the hippocampus of precoxib treatment group was statistically reduced (P＜0.05).Conclusion Parecoxib can reduce the apoptosis of hippocampus neurons through inhibiting the protein expressions of Bax and caspase-3 to affect the Bcl-2 protein expression,whose mechanism may be related to the pathways of Bcl-2/Bax and Caspase-3 proteins.

Objective:To develop a deep transfer learning method for the differential diagnosis of osteonecrosis of the femoral head (ONFH) with other common hip diseases using anteroposterior hip radiographs.Methods:Patients suffering from ONFH, DDH, and other hip diseases including primary hip osteoarthritis, non-infectious inflammatory hip disease, and femoral neck fracture treated in the First Affiliated Hospital of Guangzhou University of Chinese Medicine from January 2018 to December 2020 were enrolled in the study. A clinical data set containing anteroposterior hip radiographs of the eligible patients was created. Data augmentation by rotating and flipping images was performed to enlarge the data set, then the data set was divided equally into a training data set and a testing data set. The ResNet-152, a deep neural network model, was used in the study, but the original Batch Normalization was replaced with Transferable Normalization to construct a novel deep transfer learning model. The model was trained to distinguish ONFH and DDH from other common hip diseases using anteroposterior hip radiographs on the training data set and its classification performance was evaluated on the testing data set.Results:The clinical data set was comprised of anteroposterior hip radiographs of 1024 hips, including 542 with ONFH, 296 with DDH, and 186 with other common hip diseases (56 hips with primary osteoarthritis, 85 hips with non-infectious inflammatory osteoarthritis, 45 hips with femoral neck fracture). After data augmentation, the size of the data set multiplied to 6144. The model was trained 100 050 times in each task. Accuracy was used as the representative parameter to evaluate the performance of the model. In the binary classification task to identify ONFH, the best accuracy was 95.80%. As for the multi-classification task for classification of ONFH and DDH from other hip diseases, the best accuracy was 91.40%. The plateau of the model was observed in each task after 50 000 times of training. The mean accuracy in plateaus was 95.35% (95% CI: 95.33%, 95.37%), and 90.85% (95% CI: 90.82%, 90.87%), respectively. Conclusion:The present study proves the encouraging performance of a deep transfer learning method for the first-visit classification of ONFH, DDH, and other hip diseases using the convenient and economical anteroposterior hip radiographs.

Objective:To identify the risk factors for functional delayed gastric emptying(FDGE)after retroperitoneal tumor resection.Meth-ods:Sixty-seven patients with postoperative FDGE after retroperitoneal tumor resection from September 2017 to December 2022 admited in Peking University International Hospital were included in the observation group,and 836 normal patients who underwent ret-roperitoneal tumor resection during the same period were included in the control group.Medical histories and clinical treatment data were obtained for each group and compared to identify the risk factors for FDGE after retroperitoneal tumor resection.Results:The overall incid-ence of postoperative FDGE was 7.42%.Factors that were significantly elevated(P<0.05)in the observation group relative to the control group included adverse mental factors(37.31%),preoperative digestive tract obstruction(41.79%),postoperative abdominal cavity complic-ations(79.10%),diabetes(29.86%),average age of(61.85±6.11)years,and blood loss(1 011.94±507.30)mL.Pre-and post-surgery albumin levels[(38.22±3.75)g/L and(30.22±3.36)g/L,respectively]were significantly reduced(P<0.05)in the observation group compared to the control group.Risk factor analyses revealed that advanced age,diabetes,preoperative digestive tract obstruction,intraoperative blood loss,perioperative albumin level,postoperative abdominal cavity complications,and adverse mental factors were correlated with postoperative FDGE.Conclusions:Diverse factors could impact the risk of FDGE after retroperitoneal tumor resection.Patients should be accurately evalu-ated;reasonable and detailed prevention and treatment plans should be developed.

Objective:To introduce a novel technique note about anterior decompression through transoral axis slide and rotation osteotomy (ASRO) and identify its imaging parameters related to osteotomy, and to explore its clinical application value.Methods:CT data of cervical spine of 90 subjects were collected, including 54 males and 36 females. The age ranged from 26 to 72 years, with an average age of 48.7 years. The Mimics software was used to reconstruct the atlantoaxial three-dimensional model. We plan to perform osteotomy on both sides of the axis of the vertebral body in the anteroposterior direction and the ASRO related anatomical parameters were measured, including the minimum osteotomy angle, the maximum osteotomy angle, the minimum and maximumdistance between the osteotomy trajectory and the inner side of the articular surface, the length of the upper articular surface of the axis side mass, the depth of osteotomy at the highest point and lowest point of the axial osteotomy surface and the minimum osteotomy depth. A 56-year-old female patient was admitted to the hospital due to atlantoaxial dislocation with failure of occipital-cervical fusion, difficulty walking, weakness and hypoaesthesia in four limbs. Imaging revealed that narrow space between the transversal walking wire and upper-posterior of the odontoid process, compressing the spinal cord from the front and the back respectively. The ASRO technique was performed on the patient under neuro-electrophysiological monitoring, and the osteotomy angle, osteotomy depth, narrowest width of the upper cervical spinal canal, the medullary, spinal cord angle were measured and Japanese Orthopaedic Association Scores (JOA) cervical myelopathy evaluation were performed after the operation to evaluate the surgical treatment effect.Results:The minimum osteotomy angle and the maximum osteotomy angle was 14.7°± 4.36° and 33.0°± 8.67°. The minimum and maximumdistance between the osteotomy trajectory and the inner side of the articular surface, and the length of the upper articular surface of the axis side mass was 6.0±1.80 mm, 12.2±3.17 mm, and 17.2±1.90 mm, the ratio of the former two to the latter was 34%±8.7% and 70%± 15.0%. The depth of osteotomy at the upper edge, lower edge and narrowest place of the axial osteotomy surface were 6.0±1.80 mm, 12.2±3.17 mm and 17.2±1.90 mm. The postoperative imaging of the patient showed that the osteotomy angle was 17.1° on left side and 16.5° on right side, and the depth of osteotomy at the upper edge, lower edge and narrowest place of the axial osteotomy surface were 17.1 mm, 13.2 mm, and 9.1 mm on left side, and 17.4 mm, 11.8 mm, 8.46 mm on right side. All measured values met the ranges which were shown in the imaging anatomical study. The narrowest width of the upper cervical spinal canal increased from 6.58 mm to 15.28 mm, the medullary spinal cord angle increased from 131.7° to 153.8°postoperatively, and the cervical spine JOA score recovered from 6 points to 14 points, suggesting that the postoperative spinal canal space is obvious increased, the compression on the front of the spinal cord was significantly reduced. The patient's symptoms improved significantly.Conclusion:ASRO technique is a good choice for salvage of failed posterior occipitocervical fusion and some irreducible atlantoaxial dislocation because of the anterior bony fusion. It could direct decompress the spinal cord anteriorly, avoid the odontoid resection, which is a safe and feasible new technique.