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find Keyword "force" 67 results
  • APPLICATION OF BIOLOGICAL MESH FOR RECONSTRUCTION OF PELVIC FLOOR IN PATIENTS WITH PERINEAL HERNIA

    ObjectiveTo investigate the effectiveness of repair procedure using biological mesh with Onlay-Reinforce technique in patients with perineal hernia. MethodsBetween January 2005 and December 2012, 9 patients with perineal hernia after laparoscopic abdominoperineal resection for rectal cancer (Miles operation) were treated. There were 3males and 6 females with a mean age of 70 years (range, 61-78 years). The disease duration was 1-9 months (mean, 4.5 months). The most beginning symptom was distending pain in perineal region, and then reducible mass was found without bowel incarceration. All patients underwent hernia repair using biological mesh with Onlay-Reinforce technique through original perineal incision. ResultsThe hernial size was 9.8-20.5 cm2 (mean, 16.0 cm2); the size of biological mesh was 58-80 cm2 (mean, 70.2 cm2); and the intraoperative blood loss was 10-80 mL (mean, 50.5 mL). All of the patients underwent repair operation successfully. The operation time was 45-90 minutes (mean, 60.6 minutes); and the hospitalization time was 4-7 days (mean, 5.9 days). One patient had urine retention, which was relieved after 7 days indwelling catheter. All the wounds healed by first intention without infection. The patients were followed up 14.5-60.7 months (mean, 37.8months). No chronic pain, obvious foreign body sensation, or hernia recurrence developed. ConclusionUse of biological mesh with Onlay-Reinforce technique for the repair of perineal hernia after Miles operation is safe and effective.

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  • Musculoskeletal multibody dynamics investigation for the different medial-lateral installation position of the femoral component in unicompartmental knee arthroplasty

    The surgical installation accuracy of the components in unicompartmental knee arthroplasty (UKA) is an important factor affecting the joint function and the implant life. Taking the ratio of the medial-lateral position of the femoral component relative to the tibial insert (a/A) as a parameter, and considering nine installation conditions of the femoral component, this study established the musculoskeletal multibody dynamics models of UKA to simulate the patients’ walking gait, and investigated the influences of the medial-lateral installation positions of the femoral component in UKA on the contact force, joint motion and ligament force of the knee joint. The results showed that, with the increase of a/A ratio, the medial contact force of the UKA implant was decreased and the lateral contact force of the cartilage was increased; the varus rotation, external rotation and posterior translation of the knee joint were increased; and the anterior cruciate ligament force, posterior cruciate ligament force and medial collateral ligament force were decreased. The medial-lateral installation positions of the femoral component in UKA had little effect on knee flexion-extension movement and lateral collateral ligament force. When the a/A ratio was less than or equalled to 0.375, the femoral component collided with the tibia. In order to prevent the overload on the medial implant and lateral cartilage, the excessive ligament force, and the collision between the femoral component and the tibia, it is suggested that the a/A ratio should be controlled within the range of 0.427−0.688 when the femoral component is installed in UKA. This study provides a reference for the accurate installation of the femoral component in UKA.

    Release date:2023-08-23 02:45 Export PDF Favorites Scan
  • Optimal Solution and Analysis of Muscular Force during Standing Balance

    The present study was aimed at the optimal solution of the main muscular force distribution in the lower extremity during standing balance of human. The movement musculoskeletal system of lower extremity was simplified to a physical model with 3 joints and 9 muscles. Then on the basis of this model, an optimum mathematical model was built up to solve the problem of redundant muscle forces. Particle swarm optimization (PSO) algorithm is used to calculate the single objective and multi-objective problem respectively. The numerical results indicated that the multi-objective optimization could be more reasonable to obtain the distribution and variation of the 9 muscular forces. Finally, the coordination of each muscle group during maintaining standing balance under the passive movement was qualitatively analyzed using the simulation results obtained.

    Release date:2021-06-24 10:16 Export PDF Favorites Scan
  • The effects of CD44 fucosylation on fluid adhesion force of rabbit bone marrow mesenchymal stem cells

    Objective To investigate the effect of CD44 fucosylation on fluid adhesion force of rabbit bone marrow mesenchymal stem cells (BMSCs). Methods The rabbit BMSCs were isolated and purified by density gradient centrifugation combined with adherent culture method. The morphology of cells were observed by inverted microscope, and the cell surface markers of CD44, CD34, CD29, and CD105 were assessed by flow cytometry. BMSCs fucosylated by alpha-(1, 3)-fucosyltransferase Ⅵ (FTⅥ) were as the experimental group, and the non-fucosylated BMSCs were as the control group, and then the positive rate of sialyl-LewisX (sLeX) and the binding rate of E-selectin were detected by flow cytometry. The fucosylated BMSCs resuspended in Hank balanced salt solution (HBSS) were assigned as the experimental group (group A), at same time, the non-fucosylated BMSCs resuspended in HBSS solution as the study control group (group B), and the fucosylated BMSCs resuspended in HBSS solution which was added EDTA as negative control group (group C). The fluid adhesion force of rabbit BMSCs were detected by the parallel flow chamber adhesion test. Results Primary BMSCs mainly shaped as spindle and kept strong growth. The third generation BMSCs were negative for CD34, but positive for CD44, CD29, and CD105. After fucosylation, the positive rate of sLeX in the experimental group was 32.52%±1.76%, which was significantly higher than that in the control group (1.48%±0.51%) (t=29.277, P= 0.000). The binding rate of E-selectin in the experimental group was 41.05%±1.84%, which was also significantly higher than that in the control group (4.33%±0.92%) (t=35.674, P=0.000). With the increase of fluid shear force, the number of BMSCs adhering to the surface of human umbilical vascular endothelial cells (HUVEC) in group A was increased at first and then decreased, while there was few BMSCs adhering to the surface of HUVEC in groups B and C. Under the different fluid shear stress, the number of BMSCs adhered to the surface of HUVEC in group A was significantly higher than that in groups B and C (P<0.05), and there was no significant difference between groups B and C (P>0.05). Conclusion CD44 fucosylation on BMSCs can enhance the fluid adhesion force of rabbit BMSCs.

    Release date:2018-01-09 11:23 Export PDF Favorites Scan
  • Synchronous analysis of corticomuscular coherence based on Gabor wavelet-transfer entropy

    Synchronization analysis of electroencephalogram (EEG) and electromyogram (EMG) could reveal the functional corticomuscular coupling (FCMC) during the motor task in human. A novel method combining Gabor wavelet and transfer entropy (Gabor-TE) is proposed to quantitatively analyze the nonlinearly synchronous corticomuscular function coupling and direction characteristics under different steady-state force. Firstly, the Gabor wavelet transform method was used to acquire the local frequency-band signals of the EEG and EMG signals recorded from nine healthy controls simultaneously during performing grip task with four different steady-state forces. Secondly, the TE of local frequency-band was calculated and the unit area index of the transfer (ATE) was defined to quantitatively analyze the synchronous corticomuscular function coupling and direction characteristics under steady-state force. Lastly, the effect of EEG and EMG signal power spectrum on Gabor-TE analysis was explored. The results showed that the coupling strength in the beta band was stronger in EEG→EMG direction than in EMG→EEG direction, and the ATE values in the beta band in EEG→EMG direction decreased with the force increasing. It is also shown that the difference in TE values of gamma band present a varying regularity as the increase of force in both directions. In addition, EMG power spectrum was significantly correlated with the result of Gabor-TE inspecific frequency band. The results of our study confirmed that Gabor-TE can quantitatively describe the nonlinearly synchronous corticomuscular function coupling in both local frequency band and information transmission. The analysis of FCMC provides basic information for exploring the motor control and the evaluation of clinical rehabilitation.

    Release date:2017-12-21 05:21 Export PDF Favorites Scan
  • Application of thyroidectomy by meticulous capsular dissection technique through neck incision approach in treatment of 75 patients with type Ⅰ substernal goiter

    Objective To assess clinical value of thyroidectomy by meticulous capsular dissection technique through neck incision approach in treatment of 75 patients with type Ⅰ substernal goiter. Methods The clinical data of 75 patients with type Ⅰ substernal goiter in the Department of General Surgery of the Central Hospital of Xiaogan from April 2013 to April 2017 were retrospectively analyzed. These patients received the surgical resection by the meticulous capsular dissection technique with an ultrasonic scalpel and a bipolar coagulation forcep through neck incision approach. Results There were 12 Hashimoto thyroiditis, 10 thyroid adenoma, 41 nodular goiter, and 12 thyroid carcinoma in the 75 patients with type Ⅰ substernal goiter. Five cases underwent the unilateral total thyroidectomy. Fifty-eight cases underwent the bilateral total thyroidectomy. The bilateral total thyroidectomy plus central lymph node dissection were performed in the 9 patients with thyroid carcinoma, the bilateral total thyroidectomy plus central lymph node dissection plus affected ipsilateral neck lymph node dissection were performed in the 3 patients with thyroid carcinoma. The average operative time was 100 min, the average intraoperative blood loss was 50 mL, the average postoperative hospital stay was 5 d. The rate of parathyroid injury was 2.7% (2/75), the rate of hypocalcemia caused by parathyroid injury was 2.7% (2/75). There were 3 cases (4.0%) of unilateral recurrent laryngeal nerve injury, 1 case (1.3%) of the outer branch of the upper laryngeal nerve injury. There were 2 cases of tracheal partial softening in the 75 patients. None of postoperative bleeding and seroma happened. No death and the tumor recurrence and metastasis of patients happened during follow-up period. Conclusions Preliminary results in this study show that operation of meticulous capsular dissection technique with an ultrasonic scalpel and a bipolar coagulation forcep through neck incision approach in treatment of type Ⅰ substernal goiter is safe and feasible, it could effectively reduce postoperative complications of thyroidectomy, and protect parathyroid and it’s function, recurrent laryngeal nerve, and superior laryngeal nerve.

    Release date:2018-02-05 01:53 Export PDF Favorites Scan
  • Numerical study on the effect of the geometry size of multi-chamber infusion bag on its bursting force

    This study explored the variation of bursting force of multi-chamber infusion bag with different geometry size, providing guidance for its optimal design. Models of single-chamber infusion bag with different size were established. The finite element based on fluid cavity method was adopted to calculate the fluid-solid coupling deformation process of infusion bag to obtain corresponding critical bursting force. As a result, we proposed an empirical formula predicting the critical bursting force of one chamber infusion bag with specified geometry size. Besides, a theoretical analysis, which determines the force condition of three chamber infusion bag when falling from high altitude, was conducted. The proportion of force loaded on different chamber was gained. The results indicated that critical bursting force is positively related to the length and width of the chamber, and negatively related to the height of the chamber. While the infusion bag falling, the impact force loaded on each chamber is proportional to the total liquid within it. To raise the critical bursting force of in fusion bag, a greater length and width corresponding to reduced height are recommended considering the volume of liquid needed to be filled in.

    Release date:2021-10-22 02:07 Export PDF Favorites Scan
  • The Short and Medium Term Effect on Myocardial Contractile Force after Implantation of Autologous Endothelial Progenitor Cells

    Objective To study the short and medium term effect of myocardial contractile force by implantation of endothelial progenitor cells (EPCs) in the myocardial infarction model. Methods Hundred and twenty SD rats were equally and randomly divided into experimental group and control group (60 rats in each group). Acute myocardial infarction model was created by ligation of LAD. Autologous EPCs were purified from peripheral blood then implanted into the acute myocardial infarct site via topical injection. IMDM were used in control group. Specimens and muscle strip were harvested at 3, 6 weeks, 6, 8 and 12 months after EPCs implantation for contractile force study and to detect the expression of vascular endothelial growth factor(VEGF), basic fibroblast growth factor (bFGF) and Ⅷ factor by immunohistology and video image digital analysis system. Results The expression of VEGF, bFGF and the microvessel counts in experimental group were much higher than those of control group(P〈 0.01) at 3, 6 weeks and 6 months after transplantation. The contractile force in experimental group was better than that in control group(P〈0.01) at the same time. But from 8 months after implantation, the contractile force and so on were not up in the experimental group. Conclusion EPCs, after being implanted into infarct myocardium, shows the ability of improvement of the contractile performance in infarcted myocardium by means of angiogenesis and vasculogenesis and the medium term results are persistent.

    Release date:2016-08-30 06:23 Export PDF Favorites Scan
  • Analysis on the superiority of bipolar coagulation forceps combined with meticulous capsular dissection technique in thyroidectomy

    Objective To investigate the value of bipolar coagulation forceps combined with meticulous capsular dissection technique in thyroidectomy. Methods Information of 203 patients with thyroid neoplasms who underwent thyroidectomy in Longyan First Hospital from January 2014 to July 2015, were collected retrospectively. Patients were divide into control group (98 patients who had received conventional thyroidectomy) and observation group (105 patients who had received bipolar coagulation forceps combined with meticulous capsular dissection technique in thyroidectomy) according to the surgery type. Then comparison of 2 groups in incidence of recurrent laryngeal nerve injury, temporary hypocalcemia, temporary or permanent hypoparathyroidism, serum parathyroid hormone (PTH) and serum calcium was performed. Results All the operation of 203 patients went smoothly, and no operative death happened. Operation time of control group and observation group showed no obvious difference〔(68.24±16.59) minvs. (64.78±14.20) min,P>0.05〕, but the intraoperative blood loss of control group was more than observation group〔(25.44±8.35) mLvs. (16.58±5.44) mL,P<0.05〕. There were 25 patients suffered from temporary hypocalcemia after operation, including 18 patients in control group and 7 patients in observation group. There were 38 patients suffered from temporary hypoparathyroidism after operation. including 24 patients in control group and 14 patients in observation group. The incidences of temporary hypocalcemia (χ2=6.426,P<0.05) and temporary hypoparathyroidism (χ2=4.147,P<0.05) were both lower in observation group than corresponding index of control group. But no one suffered from permanent hypoparathyroidism. There were 17 patients existent hoarseness in the control group and 14 patients in observation group, but no one had cough caused by superior laryngeal nerve injury of all the patients, and the incidence of hoarseness of 2 groups had no significant difference (χ2=0.637,P>0.05). Conclusions Bipolar coagulation forceps combined with meticulous capsular dissection technique in thyroidectomy could reduce the temporary hypocalcemia and temporary hypoparathyroidism, and provide the better protection to the blood supply of parathyroid. In addition, bipolar coagulation forceps could reduce thermal injury and heighten hemostasis. So, it is worthy to perform bipolar coagulation forceps combined with meticulous capsular dissection technique in thyroidectomy.

    Release date:2017-04-01 08:56 Export PDF Favorites Scan
  • Clinical application of Taylor spatial frame in adjustment of lower extremity force line of knee medial compartmental osteoarthritis

    ObjectiveTo explore the safety and effectiveness of Taylor spatial frame (TSF) in the treatment of medial compartmental osteoarthritis (MCOA) of the knee and the adjustment of the lower extremity force line at the same time.MethodsThe clinical data of 30 patients with MCOA who underwent high tibial osteotomy (HTO) between October 2016 and April 2017 were retrospectively analyzed. According to the different fixation methods, they were divided into external fixation group (TSF external fixation, 16 cases) and internal fixation group (locking steel plate internal fixation, 14 cases). There was no significant difference between the two groups in gender, age, side, disease duration, mechanical femur tibia angle (MFTA), and other general data (P>0.05). The operation time and intraoperative blood loss of the two groups were recorded and compared; MFTA was used to evaluate the recovery of the lower extremity force line at last follow-up; Hospital for Special Surgery (HSS) score was used to evaluate the clinical effecacy before operation and at 2 weeks, 1 month, and 3 months after operation.ResultsThe operation time and intraoperative blood loss of external fixation group were significantly less than those of internal fixation group (P<0.05). All patients were followed up 9-16 months, with an average of 12 months. There were 2 cases of delayed healing in the internal fixation group and 1 case of delayed healing in the external fixation group, and all healed after symptomatic treatment. All patients in the two groups had no complication such as needle infection, nonunion at osteotomy, osteomyelitis, and so on. At last follow-up, MFTA standard was used to evaluate the recovery of force line. The results of external fixation group were all excellent, while the results of internal fixation group were excellent in 10 cases and good in 4 cases. The difference between the two groups was significant (Z=–2.258, P=0.024). The HSS scores in the two groups were significantly improved at each time point after operation, and gradually improved with time after operation (P<0.05). The HSS score of the external fixation group was significantly higher than that of the internal fixation group (t=2.425, P=0.022) at 3 months after operation; and there was no significant difference between the two groups at other time points (P>0.05).ConclusionTSF has unique advantages in HTO treatment of MCOA patients and correction of lower extremity force line, such as shorter operation time, less bleeding, firm fixation, and less complications. It can accurately adjust the lower extremity force line after operation and has good effectiveness. It is an effective and safe fixation method.

    Release date:2020-04-29 03:03 Export PDF Favorites Scan
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