1.Short period of mild hypothermia improves resuscitation outcome in a porcine model of prolonged ventricular fibrillation
Heng LI ; Zhengfei YANG ; Zitong HUANG ; Yongqin LI ; Tao YU
Chinese Journal of Emergency Medicine 2016;25(1):22-27
Objective To investigate the resuscitation outcome after a short period of mild hypothermia in porcine model of prolonged ventricular fibrillation (VF).Methods Fourteen male healthy domestic swine weighting 34 to 36 kg were used.VF was induced electrically and maintained untreated for 11 mins,followed by manual cardiopulmonary resuscitation (CPR) procedure.Two investigators initiated chest compression and bag-valve mask ventilation in pattern of 2 min rotation.A biphasic wave of 120 J electric defibrillation (ED) was attempted 6 mins after CPR.If there was no return of spontaneous circulation (ROSC),CPR was restored and ED was delivered when necessarily.Resuscitation was considered unsuccessful if absence of ROSC for 12 mins.However,if ROSC occurred,animals were randomly (random number) diveded into normothermia (NT) group and hypothermia treatment (CH) group.Animals in CH group were immediately cooled by using intravenous infusion of ice-cold saline and surface cooling.Core temperature was reduced to 32-34 degrees centigrade within 120 mins and maintained at this level for 2 h.Active rewarming was completed within 2 h until baseline body temperature was reached.Data of hemodynamic variables,blood-gas analysis and blood lactate before VF of two groups were recorded.Meawhile,cardiac output (CO),heart rate and Tc after ROSC were recorded.Neurological defect scores (NDS) were evaluated every 24 h until 96 h after ROSC.Variables were compared using either Fisher test or repeated measures analysis of variance,followed by Bonferroni for multiple comparisons.A two-sided P value <0.05 was regarded statistically significant.Results There was no significant difference in body weight,mean arterial pressure,CO,pH,pressure of end-tidal carbon dioxide (ETCO2) and lactate between groups before VF.In the period of CPR,there were also no significant difference in total resuscitation time,first shock success rate,ROSC rate,shock ROSC rate,total number of shock and doses of epinephrine.However,animals in CH group survived longer time than that in NT groups [(96.00 ± 0.00) hvs.(49.71 ±43.65) h,P=0.031].Meanwhile,the survival rate of 96 h was significantly higher in CH than that in NT (P < 0.05).For neurological function,there was a obviously better NDS in CH group than that in NT group within ROSC 96 h (P < 0.05).Conclusion Even a short duration of 2 hour mild hypothermia could improve resuscitation outcome in porcine model of 11 minute VF.
3.Study of the effects of mild hypothermia on improvement of cardiomyocyte contractility after ischemia-reperfusion in rats
Heng LI ; Zhengfei YANG ; Yue FU ; Jun ZHU ; Jun JIANG ; Tao YU ; Xiangshao FANG ; Zitong HUANG
Chinese Journal of Emergency Medicine 2011;20(11):1143-1148
Objective To study the effects of mild hypothermia on cardiomyocyte contractility improvement after ischemia-repeffusion injury and on the preservation of well-functioning mitochondrial respiratory capability.Methods A total of 50 newborn SD rats 1 ~ 2 days after delivery were sacrificed and their hearts taken to preserved in 4 ℃ cold D-hanks buffer solution with 0.12% pancreatic proteinase and collagenase and then processed with 37 ℃ water bath to collect the cardiomyocytes cultured in DMEM medium with 10% FBS for 5 days.The cardiomyocytes of rats were subjected to ischemia/reperfusion,in vitro,by oxygen and glucose deprivation(OGD)/oxygen and glucose restoration(OGR).The cardiomyocytes of rats after ischemia/reperfusion were divided into three groups:control group,hypothemia group and normothermia group.Contractile frequency and velosity were determined before OGD and 0 h,0.5h,1 h,1.5 h and 2 h after OGR.Ultrastructure changes of cardiomyocytes and mitochondrion were observed under transmission electron microscope(TEM)0 h and 2 h after OGR as well as assessment ot respiratory rate and respiratory control rate(RCR)with Clark oxygen electrode in each group.All data were analyzed with statistical software of SPSS 13.0.Results Contractile function of cardiomyocytes in hypothermia group and normothermia group declined to nadir at 0 h after OGR(P =0.000)and the contractile function of cardiomyocytes in hypothermia group was improved one hour later,compared with the normothermia group(P =0.000).Obvious swelling of mitochondrion was observed under TEM in normothermia group with little alteration after OGR.The RCR assessments indicated respiratory function in normothermia group was impaired after OGR(P =0.000)and this may be responsible for contractility dysfunction.Conclusions Mild hypothemia used after ischaemia can optimize the contractility of cardiomyocytes after a normothermia OGR,and the well-functioning respiratory capability of mitochondrion may be preserved in this process.
4.Establishment of porcine model of prolonged cardiac arrest and cardiopulmonary resuscitation electrically induced by ventricular fibrillation
Cai WEN ; Heng LI ; Xiaozhu ZHAI ; Youde DING ; Huatao ZHOU ; Zhiming OUYANG ; Zhengfei YANG ; Longyuan JIANG ; Wanchun TANG ; Tao YU
Chinese Critical Care Medicine 2017;29(6):536-541
Objective To investigate the optimal injury time point of cardiac arrest (CA) induced electrically, and establish a reproducible prolonged CA and cardiopulmonary resuscitation (CPR) model in pigs. Methods Forty healthy domestic male pigs were randomly divided into four groups, which were ventricular fibrillation (VF) 8, 10, 11, and 12 minutes groups, each group for 10 animals. In these groups, VF was induced by alternating current delivered to right ventricular endocardium and untreated for 8, 10, 11, and 12 minutes, respectively, followed by 6 minutes of CPR procedure. The resuscitation and survival outcomes were recorded. Hemodynamic parameters and arterial blood gases of animals after successful resuscitation were measured and recorded for 6 hours. Those successful resuscitation animals were regularly evaluated for the neurological deficit score (NDS) and survival outcomes every 24 hours till 96 hours after resuscitation. Results The shortest duration of CPR (minute: 6.9±1.3) and the highest successful ratio of the first defibrillation (7/10) were observed in group VF 8 minutes, and the ratio of successful resuscitation was 100%. The best coronary perfusion pressure (CPP) during the CPR, less neurological impairment, longer survival time, more stable hemodynamics, and shorter time for arterial pH and lactate level restoring to the original state after CPR were also observed in group VF 8 minutes, and no severe damage was found in those animals. The longest duration of CPR (minute:10.3±2.9) and the lowest successful ratio of the first defibrillation (1/10) were observed in group VF 12 minutes, and only 4 animals achieved restoration of spontaneous circulation (ROSC), and no animal survived to CPR 96 hours. The worst CPP during CPR and the highest NDS after resuscitation were also found in VF 12 minutes animals compared to those animals in the other groups. The injuries caused by ischemia and hypoxia in groups VF 10 minutes and VF 11 minutes were in between those of the groups VF 8 minutes and VF 12 minutes, and the duration of CPR were (7.0±2.1) minutes and (8.2±2.6) minutes. There were 9 and 7 animals achieved ROSC in groups VF 10 minutes and VF 11 minutes correspondingly, and 6 and 4 animals survived to 96 hours respectively. Obviously unstable hemodynamics was observed during the period of CPR 2 hours in the two groups. At CPR 1 hour, the heart rates (HR, beats/min) in groups VF 10 minutes and VF 11 minutes increased to 172 (155, 201) and 168 (136, 196) respectively, and the mean arterial pressures (MAP, mmHg, 1 mmHg = 0.133 kPa) declined to 97 (92, 100) and 81 (77, 100), the cardiac output (CO, L/min) decreased to 5.0 (4.0, 5.8), 3.7 (3.0, 5.4) correspondingly. Distinct injuries were found in the two groups [CPR 24-96 hours NDS in groups VF 10 minutes and VF 11 minutes: 180 (110, 255)-20 (0, 400) and 275 (223, 350)-240 (110, 400)], and the arterial pH of the two group decreased to 7.26±0.09 and 7.23±0.09 respectively, and the level of lactate (mmol/L) increased to 9.17±1.48 and 12.80±2.71 correspondingly at CPR 0.5 hour. Significantly lower pH was observed in group VF 11 minutes compared to group VF 8 minutes at CPR 0.5 hour (7.23±0.09 vs. 7.33±0.04, P < 0.05). The highest level of lactate (mmol/L) was also found at the same time point in group VF 11 minutes, which recovered to normal slowly, and was still significantly higher than groups VF 8, 10, 12 minutes (7.58±3.99 vs. 2.55±1.53, 2.13±2.00, 3.40±2.30, all P < 0.05) at CPR 4 hours. Conclusions The longer duration of CA was, the more severe damage would be, the longer CPR time would be required, and the harder of the animals to achieve ROSC. In this prolonged CA and CPR porcine model, 10-11 minutes for untreated VF, was an optimal time point with appropriate successful rate of resuscitation, survival outcomes, and post-resuscitation injuries. Therefore, we recommended 10-11 minutes might be the rational length of no-flow time in this model.
5. Progress on clinical research of hyperthermia combined with radiation therapy
Liqing ZOU ; Yida LI ; Xi YANG ; Zhengfei ZHU
Chinese Journal of Radiation Oncology 2020;29(1):69-72
Hyperthermia has been a research hot spot since it was approved by FDA as one of the 5 major therapeutic modalities for tumor since 1989. Pre-clinicaland clinical researches have confirmed the prominent radiosensitizing effect of hyperthermia. In this article, the research progress on hyperthermia combined with radiation therapy was summarized based upon clinical evidence. The challenges and issues during the procedure of hyperthermia combined with radiation therapy were analyzed from the perspectives of treatment temperature, frequency and interval time of hyperthermia, interval time and time sequence between hyperthermia and radiation therapy, etc. Besides, the application progress and prospect of hyperthermia combined with radiation therapy were reviewed, aiming to provide clinical evidence for the combination of hyperthermia and radiation therapy.
6.The biocompatibility and mechanical properties of plasma sprayed zirconia coated abutment
Zhengfei HUANG ; Zhifeng WANG ; Kaifeng YIN ; Chuanhua LI ; Meihua GUO ; Jing LAN
The Journal of Advanced Prosthodontics 2020;12(3):157-166
PURPOSE:
. The aim of this study was to evaluate the clinical performance and reliability of plasma sprayed nanostructured zirconia (NSZ) coating.
MATERIALS AND METHODS:
. This study consisted of three areas of analysis: (1) Mechanical property: surface roughness of NSZ coating and bond strength between NSZ coating and titanium specimens were measured, and the microstructure of bonding interface was also observed by scanning election microscope (SEM). (2) Biocompatibility: hemolysis tests, cell proliferation tests, and rat subcutaneous implant test were conducted to evaluate the biocompatibility of NSZ coating. (3) Mechanical compatibility: fracture and artificial aging tests were performed to measure the mechanical compatibility of NSZcoated titanium abutments.
RESULTS:
. In the mechanical study, 400 μm thick NSZ coatings had the highest bond strength (71.22 ± 1.02 MPa), and a compact transition layer could be observed. In addition, NSZ coating showed excellent biocompatibility in both hemolysis tests and cell proliferation tests. In subcutaneous implant test, NSZcoated plates showed similar inflammation elimination and fibrous tissue formation processes with that of titanium specimens. Regarding fatigue tests, all NSZ-coated abutments survived in the five-year fatigue test and showed sufficient fracture strength (407.65-663.7 N) for incisor teeth.
CONCLUSION
. In this study, the plasmasprayed NSZ-coated titanium abutments presented sufficient fracture strength and biocompatibility, and it was demonstrated that plasma spray was a reliable method to prepare high-quality zirconia coating.
7.Repeatability and Reproducibility of a New Ocular Biometer Based on Partial Coherence Interferometry and Its Agreement with IOL Master 500
Shuoshuo CHEN ; Zhengfei YANG ; Zixuan LI ; Guitong YE ; Xiao YANG ; Mengyi WANG
Journal of Sun Yat-sen University(Medical Sciences) 2024;45(3):484-492
[Objective]To assess the repeatability(intra-operator variability)and reproducibility(inter-operator variability)of a new partial coherence interferometry(PCI)-based ocular biometer,Myopia Master,and its agreement with IOL Master 500 for measuring axial length(AL)and corneal curvature(K)in children aged 8-12 years.[Methods]The same operator measured school children with the Myopia Master and the IOL Master 500 in random order to assess agreement.Additionally,some of these children received measurements from another operator using the Myopia Master to assess repeatability and reproducibility.AL,flat keratometry(Kf),steep keratometry(Ks),mean keratometry(Km),J0 and J45 were analyzed.The repeatability and reproducibility were assessed by the within-subject standard deviation(Sw),test-retest repeatability(TRT),coefficient of variation(CoV)and intra-class correlation coefficient(ICC).The agree-ment between the Myopia Master and the IOL Master 500 was assessed by Bland-Altman plots and 95%limits of agree-ment(LoA).[Results]Both repeatability and reproducibility of the Myopia Master were high for AL measurements(Sw=0.02 mm,ICC=0.999;Sw=0.04 mm,ICC=0.998),but moderate for K measurements(Sw range,0.04 to 0.12 D,ICC range,0.861 to 0.991;Sw range,0.06 to 0.20 D,ICC range,0.835 to 0.992).There were significant mean differences be-tween the Myopia Master and the IOL Master 500 in measurements of AL(-0.01±0.04)mm,Kf(-0.09±0.15)D,Ks(-0.47±0.40)D,and Km(-0.28±0.23)D,J0(0.18±0.20)D and J45(-0.01±0.12)D.[Conclusions]The Myopia Master provided high repeatability and reproducibility for AL measurements in schoolchildren with myopia,but the Myopia Master and the IOL Master 500 cannot be used interchangeably in measuring AL and K.
8.The epidemiological analysis of patients in pre-hospital medical care in large and medium-sized cities in China
Zaiqi ZHANG ; Futian LUO ; Bing CHEN ; Feng CHEN ; Caidan GONGBAO ; Li HUANG ; Jun KE ; Xin LAI ; Jiliang LI ; Jinnian LI ; Caijing LIN ; Xiang HU ; Jiatao LU ; Qinghua MENG ; Hua NING ; Yachun PEI ; Wenhui SUN ; Yuean XIONG ; Bin ZHANG ; Xingji ZHAO ; Wenwei OUYANG ; Wenbiao CHEN ; Weiying CHEN ; Yanchi GUO ; Zhengfei YANG ; Zitong HUANG
Chinese Journal of Emergency Medicine 2010;19(11):1130-1136
Objective To investigate the epidemiological information of patients in pre-hospital medical care for our large and medium-sized cities and probe the patients' characteristic. Method The data in 2008 were exported from the computer databases of 8 large and medium-sized cities' emergency medical centers in our country.The thorough records of data were conducted to statistical analysis. Results ( 1 ) The scheduling time, running time, rescue time, returning time, total time and service radius in the pre-hospital medical care group were 2.16± 1.10(min), 14.01 ±6.82(min), 12.12±5.96(min), 14.08± 6.85(min), 42.34± 20.21(min)and 8.50±4.18(km), and the above parameter in the non-death group were 2.19 ± 1.13(min), 14.15 ± 7.14(min),11.60±6.72(min), 14.92 ±6.89(min), 41.86± 19.53(minutes) and 8.63±4.31(Km), and the above parameter in the death group were 2.10± 1.08(min), 13.68 ± 7.14(min), 25.25 ± 12.34(min), 13.75±6.48(min), 54.74 ± 25.47(min) and 7.86± 3.91(Km), and the above parameter in the non-sudden cardiac death group were2.09± 1.03(min), 13.58±6.78(min), 25.53± 12.34(min), 13.60± 6.54(min), 53.79±23.77(min) and 7.67 ± 3.86(Km), and the above parameter in the sudden cardiac death group were 2.12 ±1.02(min), 14.10±7.05(min), 24.79± 12.08(min), 13.79±6.61(min), 54. 80 ± 25. 36( min) and 7.90±3.92(Km) respectively. The scheduling time, running time, returning time and service radius in the death group were less than those of the non-death group, but the rescue time and total time of the former were more than those of the latter respectively ( P < 0.05 or P < 0. 001 ). The scheduling time and returning time didn' t have significant difference between the sudden cardiac death group and the non-sudden cardiac death group respectively ( P > 0.05), but the running time, total time and service radius of the sudden cardiac death group were more than those of the non-sudden cardiac death group, and the rescue time of the former was less than that of the latter respectively ( P < 0.05 or P < 0.001 ). (2)The patients' amount in pre-hospital medical care group, the non-death group, the death group, the non-sudden cardiac death group and the sudden cardiac death group were at most in first quarter, and the least time slice of patients' amount were 4:00~ 6:00, 4:00~6:00, 4:00~ 6:00, 22:00~ 24:00, 2:00~4:00 respectively, and the most time slice of patients' amount were 20:00~ 22:00, 20:00~22:00, 8:00~ 10:00, 2:00 ~ 4:00, 8:00 ~ 10:00 respectively. (3)In 241 876 cases of pre-hospital medical care group, the patients' amount of trauma was at most, whose age grades was by far among21 ~50, and the others in sequence were nervous system, circulatory system, other group, digestive system, respiratory system and poisoning group respectively, whose age grades in nervous system, circulatory system and respiratory system was by far above 51, especially above 70. The patients' age grades in other group and digestive system had two climax age groups, which the one was 21 ~ 30, and the other was above 70. The patients' age grades in poisoning group was by far among 21 ~ 50, which the patients' amount of acute alcoholism was at the most. (4) In 12 568 cases of death group, the death amount of circulatory system, other group, respiratory system, nervous system and digestive system ranked at the lst,2nd,4th,5th 8th respectively, whose age grades was by far above 51, especially above 70,and the patients' amount of sudden cardiac death was at the most in the death amount of circulatory system. The death amount of trauma and poisoning group ranked at the 3rd, 6th respectively, whose age grades was by far among 21 ~ 50. (5)The total amount, the death amount and the sudden cardiac death amount of male patients were more than those of female patients. (6)The percentage of the death group to the pre-hospital medical care group was 5.20%, and the percentage of the sudden cardiac death group to the pre-hospital medical care group was 1.29%,and the percentage of the sudden cardiac death group to the death group was 24.87 %, and the percentage of the sudden cardiac death group to the circulatory system group was 67.33 %. Conclusions ( 1 )The trauma and the sudden cardiac death are the overriding reason of disease and the overriding reason of death in our large and medium-sized cities respectively. (2) It is very important to cut the death rate of the middle-old age patients by strengthening prevention and cure of cardiovascular and cerebrovascular diseases, discerning the critical illness early and improving the level of pre-hospital medical care. (3)It is a strong method to decrease the total amount and the death amount of the trauma, especially in traffic accident, by strengthening safety in production, observing traffic regulation and enhancing the legal awareness.
9.Three-dimensional reconstruction of human kidney based on UroMedix-3D system and its application in kidney surgery.
Jianfeng HUANG ; Shidong LÜ ; Zhengfei HU ; Chantao HUANG ; Yiwen LI ; Qiang WEI
Journal of Southern Medical University 2019;39(5):614-620
OBJECTIVE:
To explore the feasibility of rapid and accurate three-dimensional (3D) image reconstruction using Uromedix-3D software for urological surgery.
METHODS:
The original renal thin-slice enhancement CT data were obtained from patients with kidney lesions treated in our hospital between December, 2015 and October, 2018. The self-developed Uromedix- 3D system was used to reconstruct the normal kidney structures, blood vessels, collecting systems and the lesions. The spatial anatomic relationships of the structures were measured and digitized for surgical planning.
RESULTS:
3D reconstruction of the kidneys was performed in a total of 173 cases, and the mean time for reconstruction was 31.24±2.012 min. Of these cases, 147 (84.9%) had renal tumors, and 2 had renal tumors with tumor thrombus. In addition to renal tumors, the Uromedix-3D system was also used for reconstructing other lesions including UPJO, kidney stones and retroperitoneal masses. Renal artery reconstruction was performed in 170 cases, which allowed observation of the precise terminal branches (up to 7th grade arterial branch) of the artery; 109 (64%) cases showed the 5th grade arterial branch or above. Renal artery variations were detected in 37 cases, including accessory renal artery (24 cases) and multiple renal arteries (13 cases). The renal veins were reconstructed in 164 cases, and second grade or above (up to the 4th grade) vein branches were observed in 138 (84%) cases.
CONCLUSIONS
Uromedix-3D system can accurately and efficiently reconstruct the 3D structure of human kidneys and the renal lesions based on enhanced CT data. The reconstructed 3D model allows objective assessment of the spatial anatomical relationship of the lesions to provide assistance in surgical planning.
Humans
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Imaging, Three-Dimensional
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Kidney
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Kidney Calculi
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diagnostic imaging
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surgery
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Kidney Neoplasms
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diagnostic imaging
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surgery
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Tomography, X-Ray Computed
10.Electroacupuncture in the treatment of neurogenic urine retention through autophagy mediated by AMPK/mTOR pathway.
Zhengfei LI ; Ren ZHANG ; Guorui ZHAO ; Yao KUANG
Journal of Central South University(Medical Sciences) 2022;47(4):488-496
OBJECTIVES:
Electroacupuncture can enhance autophagic flow, promote neuronal regeneration, axonal and myelin remodeling to achieve the protection of spinal cord injury, but its role in neurogenic urine retention is not completely clear. This study aims to investigate whether the mechanism of electroacupuncture in the treatment of neurogenic urine retention is through autophagy mediated by adenosine monophosphate activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway.
METHODS:
A rat model of neurogenic urine retention after sacral spinal cord injury was established. The rats with successful model were randomly divided into a model group, an electroacupuncture group (electro-acupuncture for Ciliao, Zhongji, and Sanyinjiao by electronic stimulation, once a day, 20 min each time for 7 days), and an electroacupuncture+AMP-activated protein kinase (AMPK) inhibitor group (on the basis of the treatment of electroacupuncture group, 100 μg of AMPK inhibitor compound C was injected intramuscularly around the L2-3 intervertebral space on the 1st and 4th day). The normal group did not receive any treatment. The maximum bladder volume, bladder basal pressure, leak point pressure, and bladder compliance were recorded by multi-channel physiological recorder; the morphology of bladder tissue was observed by HE staining; autophagy was observed under transmission electron microscope; the expressions of LC3II and Beclin1 protein were observed by immunofluorescence staining; the protein levels of AMPK, phosphorylated-AMPK (p-AMPK), mTOR, phosphorylated-mTOR (p-mTOR), microtubule associated protein 1 light chain 3 (LC3) II and Beclin1 in bladder tissue were detected by Western blotting.
RESULTS:
Compared with the normal group, the maximum bladder capacity, leak point pressure, bladder compliance, p-AMPK, LC3II, Beclin1 protein expressions in the bladder tissue of the model group increased, and the p-mTOR protein expressions were decreased (all P<0.05); compared with the model group, the maximum bladder capacity, bladder compliance, p-mTOR protein expression in the bladder tissue of the electroacupuncture group were decreased, and the p-AMPK, LC3II, and Beclin1 protein expressions were increased (all P<0.05); compared with the electroacupuncture group, the maximum bladder capacity, bladder compliance, p-mTOR protein expression in the bladder tissue of the electroacupuncture+AMPK inhibitor group were increased, the p-AMPK, LC3II, and Beclin1 protein expressions were decreased (all P<0.05). In the model group, the bladder became larger, with unclear and varying degrees of degeneration, severe tissue damage and autophagosome appeared; the bladder of the electroacupuncture group was smaller than that of the model group, and all levels were clearly visible with autophagy bodies; the layers were slightly disordered and damaged in the electroacupuncture + AMPK inhibitor group.
CONCLUSIONS
Electroacupuncture can activate autophagy through AMPK/mTOR pathway, thereby reducing neurogenic urine retention caused by spinal cord injury.
AMP-Activated Protein Kinases
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Animals
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Autophagy
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Beclin-1
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Electroacupuncture
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Mammals
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Rats
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Rats, Sprague-Dawley
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Spinal Cord Injuries
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TOR Serine-Threonine Kinases