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The integration of MRI and linac has realized real-time MRI-guided radiotherapy and accelerated the progress of precision radiotherapy. Electrons are subjected to Lorentz force in the magnetic field, especially the electron cyclotron effect occurs at the tissue-air interface, which changes the original electron equilibrium state and brings challenges to dosimetry with MRI-Linac. In recent years, a series of studies carried out through Monte Carlo simulation and experimental measurement have suggested that the conventional dosimetry devices can be used for the dosimetry with MRI-Linac after replacing the magnetic materials, but corresponding correction factors should be introduced according to the magnetic field intensity, placement angle of the measuring device, type of the measuring device. The standardization, streamlining, and real-time dosimetry with MRI-Linac need to be further studied.
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The amino acid contents of five floral sources Chinese honeys (jujube, rape, chaste, acacia, and lungan) were measured using reversed phase high-performance liquid chromatography (RP-HPLC). The results showed that proline was the main amino acid in most of the analyzed samples. Phenylalanine presents at the highest content in chaste honey samples, and the total amino acid contents of chaste honeys were also significantly higher than those of other honey samples. Based on the amino acid contents, honey samples were classified using chemometric methods (cluster analysis (CA), principal component analysis (PCA), and discriminant analysis (DA)). According to the CA results, chaste honeys could be separated from other honeys, while the remaining samples were correctly grouped together when the chaste honey data were excluded. By using DA, the overall correct classification rate reached 100%. The results revealed that amino acid contents could potentially be used as indicators to identify the botanical origin of unifloral honeys.
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Objective To investigate the clinical efficacy of electroacupuncture and (or) massotherapy plus behavior therapy for cervical spondylosis.Methods Three hundred patients with cervical spondylosis were randomly allocated to three groups (A, B and C) by random number generated from calculator, 100 cases each. In addition to cupping and behavior therapy, group A received electroacupuncture; group B, massotherapy; group C, electroacupuncture and massotherapy. The clinical symptom and sign score was recorded in the three groups before and after treatment. The clinical therapeutic effects were compared.Results There were no statistically significant differences in the clinical control rate, marked control rate and total efficacy rate among the three groups after four and eight weeks of treatment and at the 4-month and 6-month follow-ups after treatment (P>0.05). In the three groups, there was a statistically significant difference in the clinical symptom and sign score between before treatment and after four and eight weeks of treatment or at the 4-month and 6-month follow-ups after treatment (P<0.01) and between after four weeks of treatment and after eight weeks of treatment or at the 4-month and 6-month follow-ups after treatment (P<0.01). There was no statistically significant differences in the clinical symptom and sign score among the three groups after four and eight weeks of treatment and at the 4-month and 6-month follow-ups after treatment (P>0.05). Conclusions Electroacupuncture and (or) massotherapy plus behavior therapy is an effective protocol for preventing and treating cervical spondylosis. It is characterized by simplicity, convenience, easiness and cheapness and can be provide for clinical application.
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The amino acid contents of five floral sources Chinese honeys (jujube, rape, chaste, acacia, and lungan) were measured using reversed phase high-performance liquid chromatography (RP-HPLC). The results showed that proline was the main amino acid in most of the analyzed samples. Phenylalanine presents at the highest content in chaste honey samples, and the total amino acid contents of chaste honeys were also significantly higher than those of other honey samples. Based on the amino acid contents, honey samples were classified using chemometric methods (cluster analysis (CA), principal component analysis (PCA), and discriminant analysis (DA)). According to the CA results, chaste honeys could be separated from other honeys, while the remaining samples were correctly grouped together when the chaste honey data were excluded. By using DA, the overall correct classification rate reached 100%. The results revealed that amino acid contents could potentially be used as indicators to identify the botanical origin of unifloral honeys.
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Objective To investigate the clinical efficacy of electroacupuncture and (or) massotherapy plus behavior therapy for cervical spondylosis.Methods Three hundred patients with cervical spondylosis were randomly allocated to three groups (A, B and C) by random number generated from calculator, 100 cases each. In addition to cupping and behavior therapy, group A received electroacupuncture; group B, massotherapy; group C, electroacupuncture and massotherapy. The clinical symptom and sign score was recorded in the three groups before and after treatment. The clinical therapeutic effects were compared.Results There were no statistically significant differences in the clinical control rate, marked control rate and total efficacy rate among the three groups after four and eight weeks of treatment and at the 4-month and 6-month follow-ups after treatment (P>0.05). In the three groups, there was a statistically significant difference in the clinical symptom and sign score between before treatment and after four and eight weeks of treatment or at the 4-month and 6-month follow-ups after treatment (P<0.01) and between after four weeks of treatment and after eight weeks of treatment or at the 4-month and 6-month follow-ups after treatment (P<0.01). There was no statistically significant differences in the clinical symptom and sign score among the three groups after four and eight weeks of treatment and at the 4-month and 6-month follow-ups after treatment (P>0.05). Conclusions Electroacupuncture and (or) massotherapy plus behavior therapy is an effective protocol for preventing and treating cervical spondylosis. It is characterized by simplicity, convenience, easiness and cheapness and can be provide for clinical application.
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Objective:To evaluate the feasibility and success rate of in-plane ultrasound-guided paravertebral block using laterally intercostal approach.Methods:In the study,27 patients undergoing elective thoracic surgery were selected to do paravertebral block preoperatively.The fifth intercostal space was scanned by ultrasound probe which was placed along the long axis of the rib and 8 cm lateral to the midline of the spine.The needle was advanced in increments aiming at the space between the internal and innermost intercostal muscles.Once the space between the muscles was achieved,20 mL of 0.5% (mass fraction) ropivacaine was injected and a catheter was inserted.Whether the tip of catheter was in right place was evaluated by ultrasound image.The block dermatomes of cold sensation were recorded 10,20 and 30 min after the bolus drug was given.Then 0.2% ropivacaine was infused with 6 mL/h via the catheter by an analgesia pump postoperatively.The block dermatomes of cold sensation and pain score were recorded 1,6,24 and 48 h postoperatively.Results:The first attempt success rate of catheteration was 81.48 % (22/27);the tips of catheter were proved in right places after the second or third attempt in 5 patients.The median numbers of the block dermatomes 10,20 and 30 min after the bolus drug was given were 2,3,4;the median numbers of block dermatomes were 5,5,5,4,and of pain score were 1,1,2,2 at 1,6,24,48 h postoperatively;no case of bilateral block,pneumothorax or vessel puncture occurred.Conclusion:Thoracic paravertebral block using laterally intercostal approach is feasible,which has high success rate of block and low rate of complications.
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Objective To evaluate the effect of melatonin on postoperative apoptosis in hippocampal cells of aged rats undergoing surgery under isoflurane anesthesia.Methods Sixty healthy male Sprague-Dawley rats, aged 18 months, weighing 550-610 g, were randomized into 5 groups (n=12 each) using a random number table: control group (group C), 2% isofiurane anesthesia group (group I), 2% isoflurane + melatonin group (group IM), surgery group (group S), and surgery + melatonin group (group SM).Group IM inhaled 2% isoflurane for 4 h.Group S inhaled 2% isoflurane for 4 h, and then back surgery was performed.In IM and SM groups, melatonin 10 mg/kg was injected intraperitoneally everyday for 7 consecutive days before anesthesia, while the equal volume of normal saline was given in C, I and S groups.The cognitive function was assessed using the Morris water maze test on 2nd after anesthesia.The escape latency, space exploration time spent at the original platform quadrant, and frequency of crossing the original platform were recorded.After the end of the Morris water maze test, the rats were sacrificed on that day, and the hippocampi were isolated for detection of the expression of Bcl-2, Bax and caspase-3 by Western blot.Bcl-2/Bax ratio was calculated.Results Compared with group C, the escape latency was significantly prolonged on days 1-3 after anesthesia in group I, the escape latency was significantly prolonged, the space exploration time spent at the original platform quadrant was shortened,and the frequency of crossing the original platform was decreased on days 1-3 after operation in group S,and the expression of caspase-3 and Bax was significantly up-regulated, the expression of Bcl-2 was downregulated, and Bcl-2/Bax ratio was decreased in I and S groups (P<0.05).Compared with group I, theescape latency was significantly shortened on days 1-3 after anesthesia (P < 0.05) , and no significant change was found in the expression of caspase-3, Bcl-2 and Bax, and Bcl-2/Bax ratio in group IM (P> 0.05).Compared with group S, the escape latency was significantly shortened, the space exploration time spent at the original platform quadrant was prolonged, and the frequency of crossing the original platform was increased on days 3-5 after operation, the expression of caspase-3 and Bax was significantly downregulated, the expression of Bcl-2 was up-regulated, and Bcl-2/Bax ratio was increased in group SM (P<0.05).Conclusion Melatonin can inhibit apoptosis in hippocampal cells and improve postoperative cognitive dysfunction in aged rats undergoing isoflurane anesthesia.
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Objective To learn the prevalence of overweight and obesity among city residents in Wenzhou city.Methods Byusing multistage stratified cluster sampling method,a total of 10 449 residents aged 18 years and above were selected forquestionnaires interview,physical examination and laboratory testing ,analyzed the prevalence and risk factors of overweightand obesity among city residents.Results The crude prevalence rates of overweight and obesity were 32.60% and7.70%,and the age -adjusted rate were 27.50% and 6.51%.The multivariate logistic regression analysis showed that age(OR =1.01,95%CI:1.01 -1.02)and drinking (OR =1.14,95%CI:1.02 -1.27)were risk factors of overweight andobesity,while high degree of education(OR =0.87,95%CI:0.84 -0.91)and active physical exercise (OR =0.75,95%CI:0.57 -0.98)were protective factors of overweight and obesity.The prevalence rates of hypertension,diabetes,dyslipidemia and hyperuricemia were much higher among adults with overweight and obesity,compared with that of normalweight adults (P <0.01).Conclusion Prevalence of overweight and obesity is high in Wenzhou City.Intervention shouldbe actively carried out for the prevention and control of overweight and obesity.
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Objective To investigate the effects of melatonin on choline acetyltransferase (ChAT) in the hippocampus of rats after isoflurane anesthesia.Methods Sixty male SD rats weighing 390-440 g were randomized into five groups (n =12 each):control group (group C),1% isoflurane group (group Ⅰ),1% isoflurane + melatonin group (group IM),2% isoflurane group (group J) and 2% isoflurane + melatonin group (group JM).Rats in groups IM and JM received intraperitoneal injection of melatonin (10 mg/kg) for 7 days,and rats in other groups received normal saline.On the 7th day of injection,rats in groups Ⅰ and IM inhaled 1% isoflurane for 4 hours,and rats in groups J and JM inhaled 2% isoflurane for 4 hours.One day after anesthesia,all the rats began Morris water maze to assess the learning and memory ability,which was made for continuous 5 days.At the end of probe test,6 rats in each group were randomly selected,blood samples were collected to detect plasma melatonin level,and the hippocampi were removed to evaluate the expression and activity of ChAT.The other rats were sacrificed to perform immunofluorescence to detect ChAT in hippocampal CA1 region and dentate gyrus.Results The plasma melatonin level,and the expression and activity of ChAT were significantly lower in group Ⅰ than in group C (P < 0.01).The escape latency was significantly longer,the probe time was significantly shorter,and the plasma melatonin level and the expression and activity of ChAT were significantly lower in group J than in group C (P < 0.05 or 0.01).The escape latency was significantly shorter,the probe time was significantly longer,and the plasma melatonin level and the expression and activity of ChAT were significantly higher in group IM than in group Ⅰ (P < 0.05 or 0.01).The escape latency was significantly shorter,and the plasma melatonin level and the ChAT activity were significantly higher in group JM than in group J (P< 0.05 or 0.01).Conclusion Melatonin can attenuate isoflurane-induced ChAT inhibition and thus improve the cognitive function of rats after isoflurane anesthesia.
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OBJECTIVE@#To observe the protein expression of growth associated protein-43 (GAP-43) in midbrain ventral tegmental area in morphine withdrawal rats at different time, and to evaluate the effect of GAP-43 on morphine withdrawal memory.@*METHODS@#Rat models of morphine dependent 1 week, 2 weeks and 4 weeks were established by morphine hydrochloride intraperitoneal injection with increasing doses to establish natural withdrawal. The protein expression of GAP-43 in midbrain ventral tegmental area was observed by immunohistochemical staining and the results were analyzed by Image-Pro Plus 5.1 image analysis system.@*RESULTS@#With prolongation of dependent time, the expression of GAP-43 was decreased then increased in midbrain ventral tegmental area.@*CONCLUSION@#GAP-43 could play a role in morphine withdrawal memory in midbrain ventral tegmental area.
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Animaux , Femelle , Mâle , Rats , Comportement animal/effets des médicaments et des substances chimiques , Modèles animaux de maladie humaine , Protéine GAP-43/métabolisme , Immunohistochimie , Mésencéphale/métabolisme , Morphine/effets indésirables , Dépendance à la morphine/métabolisme , Naloxone/pharmacologie , Rat Sprague-Dawley , Syndrome de sevrage/métabolisme , Facteurs temps , Aire tegmentale ventrale/métabolismeRésumé
Objective To determine the risk factors for post-operative delirium(POD)and post-operative cognitive dysfunction(POCD)in patients undergoing spine surgery.Methods One hundred and twenty ASA Ⅰ-Ⅲ of both sexes aged 50-76 yr undergoing elective spine surgery under general anesthesia were studied.POD was assessed by Delirium Rating Scale revised 98 at 2 days after operation and the patients were assigned into POD and nonPOD group.Cognitive function was assessed by Mini-Mental State Examination(MMSE)at 1 day before and 3 days after operation.The patients were diagnosed as having POCD if MMSEpre-MMSEpost ≥ 3.The palients were assigned into POCD and nonPOCD group.Executive function and depression were assessed by stroop interference test and Beck Depression Inventory(BDI)at 1 day before operation.Age,sex,education,alcohol consumption per week,a history of psychiatric disease,ASA physical status,Charlson comorbidity score,type of anesthesia,anticholinergic drug administration and VAS score at 1 day after operation were recorded.If there was signifirant difference between the 2 groups,the factor was analyzed using multi-factor logistic regression to select risk factor for incidence of POD and POC).Results Eleven patients developed POD(9.2%)and 30 patients developed POCD(25.0%).Logistic regression model showed that lower Stroop-CW,higher BDI score,higher Charlson comorbidity score and a history of psychiatric disease were risk factors for POD,while lower Stroop-CW,higher BDI score,higher Charlson comorbidity score and higher alcohol consumption per week were risk factors for POCD.Conclusion Preoperative executive dysfunction,depression and greater preoperative comorbidity are risk factors for both POD and POCD.A history of psychiatric disease is a risk factor for POD and higher alcohol consumption is a risk factor for POCD in patients undergoing spine surgery.
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<p><b>OBJECTIVE</b>To establish a non-invasive, repeatable and dynamic study method in endometriosis rat model using magnetic resonance imaging (MRI), in order to explore the magnetic resonance characteristics of the model.</p><p><b>METHOD</b>Endometrium tissues were transplanted into left abdominal walls of unmated adult female SD rats. After surgery, pathological changes were observed and MRI scanning was made for the ectopic lesions.</p><p><b>RESULT</b>The endometriosis rat model was successfully established and the ectopic lesions imaged strong hyperintense on DWI, hypointense on T1WI, hyperintense on T2WI with a clear border, without enhancement on CE-T1 WI.</p><p><b>CONCLUSION</b>The lesions can be clearly observed in the MRI images on the endometriosis rat model established by this method, which facilitates repeat experiments and continuous observation studies.</p>
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Animaux , Femelle , Humains , Rats , Endométriose , Diagnostic , Imagerie diagnostique , Anatomopathologie , Imagerie par résonance magnétique , Méthodes , Radiographie , Rat Sprague-DawleyRésumé
Objective To investigate the effects of melatonin on choline acetyltransferase (ChAT) in rat hippocampus after isoflurane anesthesia. Methods Sixty male SD rats weighing 390 - 440 g were randomized into 5 groups (n = 12 each): control group (group C), 1% isoflurane group (group Ⅰ), 1% isoflurane + melatonin group (group IM) , 2% isoflurane group (group J) and 2% isoflurane + melatonin group (group JM) . In IM and JM groups, melatonin 10 mg/kg was administered intraperitoneally once a day for 7 consecutive days, while equal volume of normal saline was given intraperitoneally instead of melatonin in C, I and J groups. Groups Ⅰ and IM inhaled 1% isoflurane and groups J and JM 2% isoflurane for 4 h on 7th day. All the rats underwent Morris water maze test on the day after anesthesia for assessment of learning and memory ability (escape latency and probe time) . The training test was performed 4 times a day for S days. Six rats randomly selected from each group were sacrificed the end of the test. The blood samples were collected for detection of plasma melatonin level by ELISA.The brain tissues were removed for determination of the expression and activity of ChAT in hippocampus by Western blot or colorimetric assay. The left rats were selected and sacrificed for determination of the number of ChAT positive neurons in hippocampal CA1 region and entate gyrus by immunofluorescence. Results The plasma melatonin level and expression and activity of ChAT were significantly lower in group I than in group C ( P < 0.01) . The escape latency was significantly longer, the probe time was significantly shorter, and the plasma melatonin level and expression and activity of ChAT were significantly lower in group J than in group C ( P < 0.05 or 0.01) . The escape latency was significantly shorter, the probe time was significantly longer, and the plasma melatonin level and expression and activity of ChAT were significantly higher in group IM than in group Ⅰ ( P < 0.05 or 0.01). The escape latency was significantly shorter and the plasma melatonin level and ChAT activity were significantly higher in group JM than in group J ( P < 0.05 or 0.01) . The results of immunofluorescent staining showed that the number of ChAT positive neurons in hippocampal CA1 region and dentate gyrus wag consistent with the changes in the measured ChAT expression. Conclusion Melatonin can reduce isoflurane-mediated inhibition of ChAT expression and activity and thus improve spatial memory impaired by isoflurane anesthesia in rats.
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<p><b>BACKGROUND</b>Early studies showed that naloxone infusion decreases the incidence of morphine-related side effects from intravenous patient-controlled analgesia. This study aimed to determine whether naloxone preserved analgesia while minimizing side effects caused by intravenous tramadol administration.</p><p><b>METHODS</b>Eighty patients undergoing general anesthesia for cervical vertebrae surgery were randomly divided into four groups. All patients received 1 mg/kg tramadol 30 minutes before the end of surgery, followed by a continuous infusion with 0.3 mg x kg(-1) x h(-1) tramadol with no naloxone (group I, n = 20), 0.05 microg x kg(-1) x h(-1) naloxone (group II, n = 20), 0.1 microg x kg(-1) x h(-1) naloxone (group III, n = 20) and 0.2 microg x kg(-1) x h(-1) naloxone (group IV, n = 20). Visual analog scales (VAS) for pain during rest and cough, nausea five-point scale (NFPS) for nausea and vomiting, and ramsay sedation score (RSS) for sedation were assessed at 2, 6, 12, 24 and 48 hours postoperatively. Analgesia and side effects were evaluated by blinded observers.</p><p><b>RESULTS</b>Seventy-eight patients were included in this study. The intravenous tramadol administration provided the satisfied analgesia. There was no significant difference in either resting or coughing VAS scores among naloxone groups and control group. Compared with control group, sedation was less in groups II, III, and IV at 6, 12, and 24 hours (P < 0.05); nausea was less in groups II, III and IV than group I at 2, 6, 12, 24 and 48 hours postoperatively (P < 0.05). The incidence of vomiting in the control group was 35% vs. 10% for the highest dose naloxone group (group IV) (P < 0.01).</p><p><b>CONCLUSION</b>A small-dose naloxone infusion could reduce tramadol induced side effects without reversing its analgesic effects.</p>
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Femelle , Humains , Mâle , Adulte d'âge moyen , Analgésie autocontrôlée , Méthodes , Analgésiques morphiniques , Utilisations thérapeutiques , Anesthésie générale , Méthodes , Vertèbres cervicales , Chirurgie générale , Perfusions veineuses , Naloxone , Utilisations thérapeutiques , Antagonistes narcotiques , Utilisations thérapeutiques , Nausée , Tramadol , Utilisations thérapeutiquesRésumé
<p><b>OBJECTIVE</b>Combined the blood biochemical markers, the renal histopathological changes and the metabonomics profile were investigated to study the toxicity differences between Aristolochia fangchi and Stephania tetrandra.</p><p><b>METHOD</b>Ten rats were randomly selected from 70 male Wistar rats as blank control group. The remaining 60 rats were divided into three groups. The two treated groups were orally administrated by 8.1 g x kg(-1) of A. fangchi and S. tetrandra respectively and the control group by equal volume of distilled water for 4weeks. Before the administrated and every 2 weeks, urine and plasma were collected and their 1H-NMR spectra were acquired, and then subjected to data process and PCA. Blood biochemical analysis and histopathological examination were carried out.</p><p><b>RESULT</b>On the 2nd weekend, the BUN of the two treated groups, the AST of A. fangchi group were all markedly higher than that of the control group (P < 0.05). Compared with the A. fangchi group, the SCr higher in the S. tetrandra group (P < 0.05). The kidney pathological changes were apparently in the two treated groups and the pathological changes in the liver apparently in the S. tetrandra group. Along with the lasting of administration to the 4th week, the BUN, ALT and AST of the two treated groups, the SCr of A. fangchi group were all significantly higher than that of the control group (P < 0.01). The renal and liver injuries in the two treated groups were all become more seriously. Comparing the A. fangchi group, the BUN, SCr and AST were all higher in the S. tetrandra group (P < 0.05). Compared with control group, the urinary concentrations of citrate, 2-oxo-glutarate, taurine, hippurate, TMAO, creatine and the plasma concentrations of 3-D-hydroxybutyrate, acetone, NAC, OAC, creatinine were all changed.</p><p><b>CONCLUSION</b>The A. fangchi and S. tetrandra all can induce the renal and liver lesion and its seriousness is correspondent to the lasting of administration. The liver and kidney toxicity of S. tetrandra are all more serious than the A. fangchi.</p>
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Animaux , Mâle , Rats , Aristolochia , Chimie , Analyse chimique du sang , Effets secondaires indésirables des médicaments , Médicaments issus de plantes chinoises , Métabolisme , Rein , Chimie , Métabolisme , Anatomopathologie , Foie , Chimie , Métabolisme , Anatomopathologie , Métabolomique , Répartition aléatoire , Rat Wistar , Stephania tetrandra , Chimie , Urine , ChimieRésumé
This paper describes the development of mobile MRI system. The system technical solution, some calculation and test results are introduced, the technical characteristics are analysed, the same performance has been realized with an MRI system equipped in a vehicle, the market of original fixed MRI system has been extended.
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Conception d'appareillage , Imagerie par résonance magnétique , Méthodes , Unités sanitaires mobiles , Conception de logicielRésumé
Objective To evaluate the biomechanical effects of using a new injectable calcium phosphate cement to consolidate the fixation of osteoporotic intertrochanteric fracture.Method Five matchod pairs of human cadaver femora were used to produce the model of intertrochanteric fracture.All fractures were fixed with dynamic hip screws(DHS),and divided into two groups.In the CPC consolidation group of each pair,CPC was used to grout the hip screw and to fill the posteromedial defect.All femora were subjected to biomechanical test.Results Under the loading of 500 N,in the CPC consolidation group,the mean axial stiffness is(691.93±18.90)N/mm and the horizontal shear stiffness is(5553.84±27.47)N/mm.The mean lateral and medial strength is(5.15±0.35)MPa and(4.13±0.24)MPa.The torsion stiffness was 0.41 and the ultimate loading is(3580±286)N.In the control group,the mean axiak stiffness is(453.45±19.75)N/mm,the horizontal shear stiffness is(3848.87±22.63)N/mm,the mean lateral and medial strength is(3.12±0.37)MPa and(1.80±0.21)MPa,and,the torsion stiffness is 0.35 and the ultimate loading is(2512±189)N.Consolidation fixation with CPC increased each of the biomechanical efficiency(P<0.05).Conclusions CPC consolidation of osteoprotic femoral head and the medial defect of intertrochanteric fracture can significantly improve the overall stability and decrease the rate of postoperative complication.
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Objective Objective To evaluate the biomechanical effects of using a new injectable calcium phosphate cement to consolidate the fixation of osteoporotic intertrochanteric fracture. Method Five matched pairs of human cadaver femora were used to produce the model of intertrochanteric fracture. All fractures were fixed with dynamic hip screws(DHS),and divided into two groups. In the CPC consolidation group of each pair, CPC was used to grout the hip screw and to fill the posteromedial defect. All femora were subjected to biomechanical test. Result Under the loading of 500 N, in the CPC consolidation group, the mean axial stiffness was (691.93±18.90) N/mm and the horizontal shear stiffness was (5553.84±27.47) N/mm. The mean lateral and medial strength was 5.15±0.35 MPa and (4.13±0.24) MPa. The torsion stiffness was 0.41 and the ultimate loading was (3580±286)N. In the control group, the mean axial stiffness was (453.45±19.75) N/mm, the horizontal shear stiffness was (3848.87±22.63) N/mm, the mean lateral and medial strength was (3.12±0.37) MPa and (1.80±0.21) MPa, and, the torsion stiffness was 0.35 and the ultimate loading was (2512±189)N. Consolidation fixation with CPC increased each of the biomechanical efficiency(P<0.05). Conclusion CPC consolidation of osteoprotic femoral head and the medial defect of intertrochanteric fracture could significantly improve the overall stability and decrease the rate of postoperative complication.
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Objective To evaluate the biomechanical effects of using a new injectable calcium phosphate cement to consolidate the fixation of osteoporotic intertrochanteric fracture.Method Five matchod pairs of human cadaver femora were used to produce the model of intertrochanteric fracture.All fractures were fixed with dynamic hip screws(DHS),and divided into two groups.In the CPC consolidation group of each pair,CPC was used to grout the hip screw and to fill the posteromedial defect.All femora were subjected to biomechanical test.Results Under the loading of 500 N,in the CPC consolidation group,the mean axial stiffness is(691.93±18.90)N/mm and the horizontal shear stiffness is(5553.84±27.47)N/mm.The mean lateral and medial strength is(5.15±0.35)MPa and(4.13±0.24)MPa.The torsion stiffness was 0.41 and the ultimate loading is(3580±286)N.In the control group,the mean axiak stiffness is(453.45±19.75)N/mm,the horizontal shear stiffness is(3848.87±22.63)N/mm,the mean lateral and medial strength is(3.12±0.37)MPa and(1.80±0.21)MPa,and,the torsion stiffness is 0.35 and the ultimate loading is(2512±189)N.Consolidation fixation with CPC increased each of the biomechanical efficiency(P<0.05).Conclusions CPC consolidation of osteoprotic femoral head and the medial defect of intertrochanteric fracture can significantly improve the overall stability and decrease the rate of postoperative complication.
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Objective To evaluate the biomechanical effects of using a new injectable calcium phosphate cement to consolidate the fixation of osteoporotic intertrochanteric fracture.Method Five matchod pairs of human cadaver femora were used to produce the model of intertrochanteric fracture.All fractures were fixed with dynamic hip screws(DHS),and divided into two groups.In the CPC consolidation group of each pair,CPC was used to grout the hip screw and to fill the posteromedial defect.All femora were subjected to biomechanical test.Results Under the loading of 500 N,in the CPC consolidation group,the mean axial stiffness is(691.93±18.90)N/mm and the horizontal shear stiffness is(5553.84±27.47)N/mm.The mean lateral and medial strength is(5.15±0.35)MPa and(4.13±0.24)MPa.The torsion stiffness was 0.41 and the ultimate loading is(3580±286)N.In the control group,the mean axiak stiffness is(453.45±19.75)N/mm,the horizontal shear stiffness is(3848.87±22.63)N/mm,the mean lateral and medial strength is(3.12±0.37)MPa and(1.80±0.21)MPa,and,the torsion stiffness is 0.35 and the ultimate loading is(2512±189)N.Consolidation fixation with CPC increased each of the biomechanical efficiency(P<0.05).Conclusions CPC consolidation of osteoprotic femoral head and the medial defect of intertrochanteric fracture can significantly improve the overall stability and decrease the rate of postoperative complication.