Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 22
Filter
1.
Journal of Medical Biomechanics ; (6): E375-E381, 2023.
Article in Chinese | WPRIM | ID: wpr-987961

ABSTRACT

Objective To propose a new multi-joint series venipuncture system, explore the mechanics and kinematics-based related control problems involved in needle insertion and needle picking during the puncture process, and verify feasibility of this system. Methods A puncture manipulator was built, and needle displacement control algorithm was proposed by combing with the puncture mechanics model. The the forward kinematics was calculated by using DH method, so as to obtain the tip coordinates. Then the inverse kinematics was calculated by using the geometric method. The forward and inverse processes were closely connected. The position error of the end coordinates before and after needle picking was compared by using the method of kinematics positive solution-inverse solution-re-positive solution. Finally, experimental verification and simulation were conducted by combining with the physical object. Results Through simulation and experiments, accuracy of the theoretical model was verified. The needle insertion algorithm could be used to achieve success with only one needle insertion, which provided theoretical basis for the control of robot arm. The position error before and after needle picking could be controlled within 1 mm from the end trajectory. The end needle tip of robot arm was almost kept fixed during the needle picking process. Therefore, this needle picking scheme was feasible and could basically verify that the needle picking action of robot arm met the accuracy and safety requirements. Conclusions The venipuncture manipulator truly simulates the needle insertion and needle picking action during the puncture process, and can safely and accurately realize the needle insertion and needle picking action with needle tip as the fixed point, indicating that it has certain clinical value.

2.
Chinese Journal of Nuclear Medicine and Molecular Imaging ; (6): 607-612, 2021.
Article in Chinese | WPRIM | ID: wpr-910806

ABSTRACT

Objective:To analyze the differences in 18F-fluorodeoxyglucose (FDG) PET/CT imaging and preoperative localization between patients with temporal lobe epilepsy (TLE) and extratemporal epilepsy (ETLE) caused by focal cortical dysplasia (FCD). Methods:From April 2015 to August 2018, a total of 71 patients (45 males, 26 females, age (24.3±9.1) years) with refractory epilepsy who underwent 18F-FDG PET/CT imaging before surgery and confirmed as FCD by pathology in Xuanwu Hospital were retrospectively analyzed. Patients were divided into TLE and ETLE groups based on pathological results. 18F-FDG PET/CT images were analyzed qualitatively and compared with the operation result, then region of interest (ROI) was used to calculate the asymmetry index (AI), and evaluated the hypometabolism of every cerebral region by |AI| semi-quantitatively. Engle classification were followed-up after surgery. Independent-sample t test and χ2 test were used to analyze data. Results:Of 71 FCD patients, 35 were TLE and 36 were ETLE. The onset age of ETLE patients were younger than TLE patients ((10.1±6.5) vs (14.9±9.7) years; t=2.48, P=0.02). In TLE group, 54.29%(19/35) were completely consistent with the operation results, and 42.86%(15/35) showed hypometabolized brain regions in extratemporal lobe. In ETLE group, 27.78%(10/36) were completely consistent with the operation results, and 47.22%(17/36) showed hypometabolized brain regions in temporal lobe. There were significant differences in the lateral accuracy and positioning accuracy of 18F-FDG PET/CT between TLE and ETLE patients (97.14%(34/35) vs 75.00%(27/36), 54.29%(19/35) vs 27.78%(10/36); χ2 values: 7.19, 6.27, both P<0.05). There was no significant difference in |AI| values between the brain regions of TLE and ETLE patients ( z values: from -1.25 to -0.06, all P>0.05). Conclusion:The lateral accuracy and positioning accuracy of 18F-FDG PET/CT in TLE patients are better than that in ETLE patients.

3.
Chinese Journal of Nuclear Medicine and Molecular Imaging ; (6): 410-414, 2021.
Article in Chinese | WPRIM | ID: wpr-910780

ABSTRACT

Objective:To explore the accuracy of 18F-fluorodeoxyglucose (FDG) PET/MR in preoperative localization of refractory epilepsy patients with conventional MRI negative. Methods:From August 2016 to December 2018, 57 refractory epilepsy patients (36 males, 21 females, age (24.0±10.3) years) with conventional MRI negative who underwent surgery in Xuanwu Hospital were retrospectively enrolled. All patients received interictal 18F-FDG PET/MR before surgery and the epileptogenic foci were determined by using visual and semi-quantitative methods. Patients were followed up for 1 year and the surgical outcome was evaluated according to Engel classification. The sensitivity, specificity and accuracy of 18F-FDG PET/MR in locating epileptogenic foci were calculated according to surgical resection and followed-up results as the " gold standard" . Results:Of 57 patients, 51(89.5%, 51/57) showed single or multiple hypo-metabolism focus on 18F-FDG PET/MR, and 6(10.5%, 6/57) showed no abnormal metabolism changes. The microstructure abnormality was found in 18 patients (31.6%, 18/57) on 18F-FDG PET/MR images. Follow-up results were obtained from 46 patients, and 84.8%(39/46) with seizure improvement (Engel Ⅰ-Ⅲ). The sensitivity, specificity and accuracy of 18F-FDG PET/MR in preoperative localization of epileptic foci was 90.0%(27/30), 3/16 and 65.2%(30/46), respectively. Conclusion:18F-FDG PET/MR is helpful for the detection of epileptic foci in patients with MRI-negative refractory epilepsy, and can provide reliable information for further surgical treatment.

4.
Chinese Journal of Orthopaedics ; (12): 1434-1442, 2021.
Article in Chinese | WPRIM | ID: wpr-910733

ABSTRACT

Objective:To evaluate the effects of weight-bearing area compression injury of the femoral head on the prognosis of elderly acetabular fractures after open reduction and internal fixation.Methods:A retrospective analysis of 36 elderly patients with acetabular fractures treated with open reduction and internal fixation during January 2014 to January 2018 were conducted. All patients with compression injury of the weight-bearing area of the femoral head, including 22 males and 14 females with 73.2±6.5 years old (range 60-87 years old), were included. The compression injury of weight-bearing area of the femoral head was not treated. According to the Letournel-Judet classification of acetabular fractures, there were 14 cases with both-column, 12 cases with anterior column and posterior hemitransverse, 4 cases with T type, 4 cases with transverse, and 2 cases with posterior column+ posterior wall. A total of 14 cases were accompanied by acetabular joint surface compression, while 29 cases were accompanied by joint dislocation. The Merle d'Aubigné score was used to evaluate the hip function during follow-up. The Matta classification method was used to evaluate the results of acetabular fracture reduction. The Kellgren-Lawrence classification standard and Ficat-Alert staging method were used to evaluate the traumatic arthritis of the hip and femoral head necrosis, respectively. During the follow-up, the femoral head necrosis with stage III, IV, or traumatic arthritis III, IV, or with indications for joint replacement was defined as surgery failure. CT scans of the pelvis were performed before and at 2-5 days after operation. The compression size of the femoral head on the coronal and axial planes of the CT scan was calculated for the compression volume. The compression severity was divided into small (<1 cm 3), medium (1-2 cm 3) and large (>2 cm 3) according to the volume. Binary Logistic regression analysis was used to analyze whether the postoperative measurement of the femoral head compression volume was associated with the risk of surgical failure. Results:All patients were followed up for 34.7±8.9 months (range 25-54 months). There were 7 cases with large compression of femoral head, 14 cases with medium, and 15 cases with small pre-operatively. However, there were 12 cases, 10 cases and 14 cases with large, medium and small at 2-5 days after operation, respectively. Six cases were excellent reduction, 22 cases were good, and 8 cases were poor. Thus, the excellent and good rate was 78% (28/36). At the last follow-up, Merle d'Aubigné score was excellent in 2 cases, good in 8 cases, fair in 5 cases, and poor in 21 cases. The excellent and good rate was 28% (10/36). There were 20 cases with surgery failure with 56% (20/36) failure rate. There were no statistically significant differences in the patient's age, body mass index, operation duration, blood volume, fracture type, fracture reduction, combined acetabular joint surface compression, and combined joint dislocation between the two groups. However, there was a statistically significant difference in the frequency distribution of compression volume in the weight-bearing area of the femoral head after surgery (χ 2=22.047, P<0.001). In patients with large, medium, and small-volume compression of the femoral head weight-bearing area, the surgery failure rates were 92%, 80%, and 7%, respectively. The large and medium-volume compression of the femoral head weight-bearing area were independent risk factors for surgical failure. Conclusion:Open reduction and internal fixation can be used to treat elderly patients with acetabular fractures combined with femoral head compression injury. Despite satisfactory reduction for acetabular fractures, the larger volume of femoral head compression affects the clinical outcomes with extremely high rate of surgical failure within 2 years.

5.
Chinese Journal of Orthopaedic Trauma ; (12): 592-596, 2021.
Article in Chinese | WPRIM | ID: wpr-910011

ABSTRACT

Objective:To explore the association between location of lower extremity deep venous thrombosis and incidence of pulmonary embolism in patients with lower extremity fracture during hospitalization.Methods:A retrospective study was conducted of the 1,620 patients who had been treated for lower extremity fracture and deep vein thrombosis from October 2014 to November 2019 at Department of Orthopaedic Trauma, Honghui Hospital. They were 726 males and 894 females, aged from 18 to 98 years (average, 64.0 years). By the anatomical location of thrombosis, they were divided into a proximal thrombosis group and a distal thrombosis group; by the laterality of thrombosis, they were divided into a bilateral thrombosis group and a unilateral thrombosis group which was further divided into a left thrombosis subgroup and a right thrombosis subgroup. The incidences of pulmonary embolism were compared between 2 corresponding groups and subgroups.Results:Pulmonary embolism occurred in 13 of the 1,400 patients with distal thrombosis and in 12 of the 220 patients with proximal thrombosis; the incidence of pulmonary embolism in the proximal thrombosis group (5.45%, 12/220) was significantly higher than that in the distal thrombosis group (0.93%, 13/1,400) ( P<0.001). Pulmonary embolism occurred in 10 of the 337 patients with bilateral thrombosis and in 15 of the 1,283 patients with unilateral thrombosis; the incidence of pulmonary embolism in the bilateral thrombosis subgroup (2.97%, 10/337) was significantly higher than that in the unilateral thrombosis group (1.17%, 15/1,283) ( P=0.017). Pulmonary embolism occurred in 5 of the 677 patients with left thrombosis and in 10 of the 606 patients with right thrombosis; the incidence of pulmonary embolism in the right thrombosis subgroup (1.65%, 10/606) was insignificantly higher than that in the left thrombosis subgroup (0.74%, 5/677) ( P=0.129). Conclusions:In patients with lower extremity fracture, those with proximal or bilateral thrombosis are more prone to pulmonary embolism than those with distal or unilateral thrombosis, but the possibility of pulmonary embolism cannot be ignored clinically in those with distal or unilateral thrombosis.

6.
Journal of Medical Biomechanics ; (6): E101-E107, 2020.
Article in Chinese | WPRIM | ID: wpr-804517

ABSTRACT

Objective To investigate the influence of gravity levels on lower limb motions during human walking. Methods A suspended microgravity simulation system was designed for the experiment. Kinetic parameters from lower limb joints of twelve volunteers during walking were measured by the motion capture system and 3D force plate under simulated Mars gravity (1/3 G), lunar gravity (1/6 G) and earth gravity (1 G). Results Under simulated Mars and lunar gravity, the ranges of motion (ROMs) of hip and knee joints in sagittal plane significantly decreased (P<0.01) while the ROMs of ankle joints obviously increased (P<0.05). The ROMs of hip, knee and ankle joints in sagittal plane under earth gravity were 45.2°, 67.7°, 32.5°, respectively, while the ROMs of hip, knee and ankle joints under lunar gravity were 25.1°, 50.8°, 42.4°, respectively. In addition, the force and torque of lower limb joints in sagittal plane under lower gravity also decreased significantly (P<0.01). Conclusions The results obtained by this study were almost the same as the research findings obtained by using treadmill. Astronauts can use the treadmill and microgravity simulation system for walking exercises under lunar gravity on the earth.

7.
Chinese Journal of Orthopaedic Trauma ; (12): 489-494, 2020.
Article in Chinese | WPRIM | ID: wpr-867886

ABSTRACT

Objective:To compare the predictive values between 4 risk assessment scales for deep venous thrombosis (DVT) in patients with pelvic or acetabular fracture.Methods:The clinical data of 235 patients with pelvic or acetabular fracture were retrospectively analyzed who had been admitted to Xi'an Honghui Hospital from July 2014 to July 2018. They were 168 males and 67 females, aged from 18 to 90 years (average, 43.5 years). They were divided into a DVT group and a DVT-free group according to the results of vein ultrasongraphy. The RAPT, Caprini, Wells, and Autar scales were used respectively to assess the risk of DVT in the patients. The 2 groups were compared in terms of the scores of the 4 scales. After the receiver operating characteristic curve (ROC) was drawn and the area under the ROC curve (AUC) was calculated, the predictive values of the 4 scales were evaluated for lower limb DVT in the patients with pelvic or acetabular fracture.Results:Of the 235 patients, 104 (44.3%) had DVT. There was no statistically significant difference in the preoperative general data between the 2 groups, showing comparability ( P>0.05). The DVT group scored significantly higher in RAPT, Wells and Autar scales than the DVT-free group( P<0.05). The AUCs for the RAPT, Caprini, Wells, and Autar scales were respectively 0.84±0.02, 0.65±0.05, 0.81±0.02 and 0.72±0.03, showing significant differences ( F=1.254, P=0.031). The AUCs for RAPT and Wells scales were significantly higher than those for Caprini and Autar scales, and the AUS for Autar scale was significant higher than that for Caprini ( P<0.05). The sensibilities for RAPT, Caprini, Wells and Autar scales were respectively 94.0%, 65.0%, 90.6% and 84.0% while the specificities for them 62.1%, 51.8%, 67.2% and 32.5%. Conclusion:Although all the 4 scales have a certain predictive value for the DVT risk in patients with pelvic or acetabular fracture, RAPT and Wells scales are more valuable.

8.
Chinese Journal of Orthopaedic Trauma ; (12): 1036-1040, 2019.
Article in Chinese | WPRIM | ID: wpr-799895

ABSTRACT

Objective@#To explore the application of Doppler ultrasound to assess the stability of pelvic ring in treatment of lateral-compression-1 (LC-1) pelvic fractures.@*Methods@#For this prospective study 38 patients with LC-1 pelvic fracture were enrolled who had been admitted to the Department of Orthopedic Trauma, Honghui Hospital from July 2016 to November 2017. They were 22 men and 16 women with an age of 55.2±16.1 years. After the patient's condition was stable, they underwent a Doppler ultrasound examination in the pelvic compression separation test. According to the criteria preset: those with a left-right mobility ≥ 0.3 cm were assigned as an unstable group (16 cases) and those with a mobility<0.3 cm as a stable group (22 cases). The stable group received conservative treatment while the unstable group surgical treatment. The 2 groups were compared in terms of mobility of fracture ends, follow-up time, weight-bearing time, fracture healing time, and the Majeed scores of pelvic function at the last follow-up.@*Results@#The 2 groups were compatible due to their insignificant differences in baseline data(P>0.05). The mobility of fracture ends (left-right distance: 0.45±0.22 cm; anterior-posterior distance: 0.26±0.16 cm; oblique distance: 0.50±0.23 cm) in the unstable group was all significantly greater than in the stable group (left-right distance: 0.11±0.03 cm; anterior-posterior distance: 0.05±0.04 cm; oblique distance: 0.11±0.07 cm) (P<0.05). The weight-bearing time in the stable group (0.9±0.5 months) was significantly shorter than that in the unstable group (1.9±2.0 months) (Z=-2.353, P=0.019). There were no significant differences between the 2 groups in follow-up time (13.9±3.8 months versus 15.1±3.0 months), fracture healing time (4.6±1.3 months versus 4.5±1.2 months) or the Majeed scores (84.8±6.4 versus 80.3±12.2) (all P>0.05).@*Conclusions@#Since ultrasonography is helpful in assessment of the stability of LC-1 pelvic fractures, a proper treatment strategy can be decided. Stable ones can be treated conservatively and unstable ones surgically.

9.
Chinese Journal of Natural Medicines (English Ed.) ; (6): 953-962, 2019.
Article in English | WPRIM | ID: wpr-781232

ABSTRACT

Phytochemical investigation of the leaves and twigs of Callicarpa cathayana led to the isolation of six new clerodane diterpenoids, cathayanalactones A-F (1-6), together with seven analogues (7-13). Their structures were established by extensive NMR analyses together with experimental and calculated ECD spectra analyses. Compounds 1, 2, 3, 7 and 11 showed inhibitory activities on lipopolysaccharide-induced nitric oxide production in RAW264.7 cells.

10.
Chinese Journal of Orthopaedic Trauma ; (12): 1036-1040, 2019.
Article in Chinese | WPRIM | ID: wpr-824417

ABSTRACT

Objective To explore the application of Doppler ultrasound to assess the stability of pelvic ring in treatment of lateral-compression-1 (LC-1) pelvic fractures.Methods For this prospective study 38 patients with LC-1 pelvic fracture were enrolled who had been admitted to the Department of Orthopedic Trauma,Honghui Hospital from July 2016 to November 2017.They were 22 men and 16 women with an age of 55.2 ± 16.1 years.After the patient's condition was stable,they underwent a Doppler ultrasound examination in the pelvic compression separation test.According to the criteria preset:those with a left-right mobility ≥ 0.3 cm were assigned as an unstable group (16 cases) and those with a mobility < 0.3 cm as a stable group (22 cases).The stable group received conservative treatment while the unstable group surgical treatment.The 2 groups were compared in terms of mobility of fracture ends,follow-up time,weight-bearing time,fracture healing time,and the Majeed scores of pelvic function at the last follow-up.Results The 2 groups were compatible due to their insignificant differences in baseline data(P > 0.05).The mobility of fracture ends (left-right distance:0.45 ± 0.22 cm;anterior-posterior distance:0.26 ± 0.16 cm;oblique distance:0.50 ±0.23 cm) in the unstable group was all significantly greater than in the stable group (left-right distance:0.11 ± 0.03 cm;anterior-posterior distance:0.05 ± 0.04 cm;oblique distance:0.11 ±0.07 cm) (P < 0.05).The weight-bearing time in the stable group (0.9 ±0.5 months) was significantly shorter than that in the unstable group (1.9 ±2.0 months) (Z =-2.353,P=0.019).There were no significant differences between the 2 groups in follow-up time (13.9 ± 3.8 months versus 15.1 ± 3.0 months),fracture healing time (4.6 ± 1.3 months versus 4.5 ± 1.2 months) or the Majeed scores (84.8 ± 6.4 versus 80.3 ± 12.2) (all P > 0.05).Conclusions Since ultrasonography is helpful in assessment of the stability of LC-1 pelvic fractures,a proper treatment strategy can be decided.Stable ones can be treated conservatively and unstable ones surgically.

11.
Chinese Journal of Nuclear Medicine and Molecular Imaging ; (6): 777-781, 2018.
Article in Chinese | WPRIM | ID: wpr-708949

ABSTRACT

Objective To investigate the value of PET/CT imaging of cerebral glucose metabolism (CGM)and cerebral blood flow (CBF)in evaluating chronic disorders of consciousness (CDC).Methods A total of 10 CDC patients (5 males,5 females,age (50.9 ±17.2)years)and 10 healthy controls (5 males,5 females,age (52.0±10.3)years)from January 2016 to March 2017 were recruited to perform brain PET/CT of CGMand CBF.The brain PET imaging using 13 N-Ammonia was performed and followed by 18 F-fluorodeoxyglucose (FDG)PET.The mean standardized uptake values (SUVmean )of frontal,parietal, temporal and occipital lobes as well as basal ganglia,thalamus were obtained.The SUVmean of cerebral re-gions/SUVmean of cerebellum ratios (SUVr )were acquired.The SUVr were compared between the patients and controls.The imaging characteristics of CGM and CBF were investigated,and their relationships with clinical scores were further analyzed.Two-sample t test and Pearson correlation analysis were used to analyze the data.Results The radioactive distribution in the brain of healthy controls was symmetrical.SUVr of cer-ebral regions in the affected side of patients were significantly lower than those of the controls both in CGM imaging and CBF imaging (t values:2.90-5.19,all P<0.05).In 10 CDC patients,there were 9 with hypo-metabolism in basal ganglia and thalamus,8 with hypometabolism in frontal and parietal lobes,and 7 with hypometabolism in temporal and occipital lobes.At the same time,there were 7 with parietal hypoperfusion and 6 with hypoperfusion in other cerebral regions in the CDC patients.In the frontal,parietal lobes and basal ganglia,the CGMand CBF were both correlated with the clinical scores (r values:0.473-0.606,all P<0.05).Abnormal metabolism-perfusion patterns were divided into 3 types.Type Ⅰ included 2 patients and their hypometabolism and hypoperfusion were mismatched completely.Type Ⅱ included 3 patients and their hypometabolism and hypoperfusion were matched in frontal,parietal,occipital and temporal lobes,while mismatched in basal ganglia and thalamus.Type Ⅲ included 5 patients and their hypometabolism and hypoperfusion were matched completely.The clinical scores of typeⅠ,Ⅱand Ⅲ were 10.5,8.3 and 5.6, respectively.Conclusion The PET/CT imaging of cerebral blood flow and metabolism is useful in evalua-ting the disorders of consciousness.

12.
Chinese Journal of Orthopaedic Trauma ; (12): 510-514, 2018.
Article in Chinese | WPRIM | ID: wpr-707513

ABSTRACT

Objective To compare the perioperative incidence of deep venous thrombosis (DVT) and level of plasma D-dimer between different ages in patients with lower limb fracture in Northwest China.Methods The data were retrospectively analyzed of the 1,185 patients with lower limb fracture in 5 provinces in Northwest China from July 2014 to March 2017.They were 583 males and 602 femals,with an average of 60.3 years(from 18 to 102 years).Of them,723 were from Shaanxi Province,148 from Gansu Province,137 from Qinghai Province,128 from Ningxia Hui Nationality Autonomous Regions and 49 from Xinjiang Uygur Autonomous Region.They were divided into a young group (≤44 years old) (n =288),a middle-aged group (from 45 to 59 years old) (n =256),a junior elderly group (from 60 to 74 years old) (n =263),and a senior elderly group (≥75 years old) (n =378).The incidences of perioperative deep venous thrombosis (DVT) and levels of plasma D-dimer were compared between the 4 age groups.Results The DVT incidences before and after operation in the young group were significantly lower than in the other 3 groups (P < 0.05);the DVT incidence after operation in the middle-aged group was significantly lower than that in the junior elderly group (P < 0.05).The pre-and post-operative levels of plasma D-dimer increased with the age of the patients;the pre-and post-operative levels of plasma D-dimer in the senior elderly group were significantly higher than in the other 3 groups (P < 0.05).Conclusions The perioperative incidence of DVT was high in the elderly patients with lower limb fracture in Northwest China,peaking in the age range from 60 to 74 years old.The pre-and post-operative levels of plasma D-dimer increased with the age of the patients.

13.
Chinese Journal of Orthopaedic Trauma ; (12): 941-947, 2017.
Article in Chinese | WPRIM | ID: wpr-663104

ABSTRACT

Objective To investigate the incidence and risk factors of deep venous thrombosis (DVT) of lower extremity in patients with pelvic or acetabular fracture.Methods From August 2015 to December 2016,110 patients with pelvic or acetabular fracture were treated in our hospital.They were 76 males and 34 females with a mean age of 44.2 years (range,from 16 to 76 years).There were 48 pelvic fractures,including 12 anterior and posterior compression,16 lateral compression and 20 vertical shear ones by the Young-Burgess classification;there were 62 acetabular fractures,including 26 simple and 36 complex ones by the Letournel-Judet classification.The incidence of lower extremity DVT was detected preoperatively and postoperatively using ultrasound detection.The factors associated with the incidence of DVT were analyzed statistically.The risk factors were screened by single factor logistic regression analysis;the major independe risk factors were determined by multi-factor logistic regression analysis.P < 0.05 was considered as statistically significant.Results DVT occurred in 32 patients (29.09%),including 21 cases (19.09%) of proximal thrombosis and 3 cases of combined pulmonary embolism.The incidence of DVT in patients with acetabular fracture was significantly higher than in those with pelvic fracture (P < 0.05);the incidence of proximal DVT in patients with complex acetabular fracture was significantly higher than in those with simple acetabular fracture (P < 0.05).Multivariate analysis showed that age of > 60 years,combined injuries and interval of > 2 weeks from injury to surgery were independent risk factors for incidence of DVT (P < 0.05).Conclusions The risk of lower extremity DVT is high in patients with pelvic or acetabular fracture in spite of active prophylaxis,especially the risk of proximal thrombosis.Age of > 60 years,combined injuries and interval of > 2 weeks from injury to surgery may be the independent risk factors for incidence of DVT.

14.
Journal of Biomedical Engineering ; (6): 187-191, 2015.
Article in Chinese | WPRIM | ID: wpr-266703

ABSTRACT

In an anti-thrombotic pressure circulatory device, relays and solenoid valves serve as core execution units. Thus the therapeutic efficacy and patient safety of the device will directly depend on their performance. A new type of testing system for relays and solenoid valves used in the anti-thrombotic device has been developed, which can test action response time and fatigue performance of relay and solenoid valve. PC, data acquisition card and test platform are used in this testing system based on human-computer interaction testing modules. The testing objectives are realized by using the virtual instrument technology, the high-speed data acquisition technology and reasonable software design. The two sets of the system made by relay and solenoid valve are tested. The results proved the universality and reliability of the testing system so that these relays and solenoid valves could be accurately used in the antithrombotic pressure circulatory equipment. The newly-developed testing system has a bright future in the aspects of promotion and application prospect.


Subject(s)
Humans , Equipment Design , Monitoring, Ambulatory , Pressure , Reproducibility of Results , Software , Thrombosis , Diagnosis
15.
Journal of Medical Biomechanics ; (6): E432-E439, 2014.
Article in Chinese | WPRIM | ID: wpr-804347

ABSTRACT

Objective To study the effect of myocardial bridge oppression on blood flow, positive pressure, circumferential stress and shear stress of the coronary artery. Methods The original myocardial bridge simulative device was greatly improved to be able to measure multi-hemodynamic parameters, such as normal stress, circumferential stress and shear stress, so as to exactly simulate real blood dynamics environment with the common effect of several stresses, and comprehensively investigate the relationship between hemodynamics and atherosclerosis of mural coronary artery under the combined effects of several stresses. Results The results from the myocardial bridge simulative device indicated that the hemodynamic abnormalities were mainly located in the proximal end of mural coronary artery, and the mean and oscillation values of normal stress at the proximal end were increased by 27.8% and 139%, respectively, showing a significant increase with the intensification of myocardial bridge oppression. Conclusions It is myocardial oppression that causes the hemodynamic abnormity of proximal coronary artery, which is quite important for understanding the hemodynamic mechanism of coronary atherosclerotic diseases and valuable for studying pathological effects and treatments of the myocardial bridge in clinic.

16.
Chinese Journal of Perinatal Medicine ; (12): 317-322, 2014.
Article in Chinese | WPRIM | ID: wpr-450859

ABSTRACT

Objective To examine the relationship between gender and intraventricular hemorrhage (IVH) in very low birth weight infants (VLBWI) and extremely low birth weight infants (ELBWI).Methods From January 1,1999 to December 31,2012,data on VLBWI and ELBWI,who were admitted to the neonatal intensive care unit of Yuying Children's Hospital within 14 d after birth,were retrospectively collected.The Chi-square test and t test were used to compare neonatal outcomes between male and female infants.The Logistic model was used to analyze the risk factors for IVH.Results A total of 1 008 cases were enrolled,including 615 males and 393 females,895 VLBWI and 113 ELBWI.The incidence of IVH was 15.1% (152/1 008) and the incidence of severe IVH was 8.4% (85/1 008).Compared with females,males had a higher total incidence of IVH [17.2% (106/615) vs 11.7% (46/393),x2=5.728,P<0.05] and severe IVH [9.8% (60/615) vs 6.4% (25/393),x2=3.896,P<0.05].These differences were also seen in VLBWI with a birth weight of 1 250 to 1 499 g [IVH:13.7% (47/344) vs 7.8% (17/217),x2=4.473,P=0.034; severe IVH:7.6% (26/344) vs 2.8% (6/217),x2=5.684,P=0.017].Logistic regression analysis showed that the risk factors for IVH were as follows:gestational age <28 weeks (aOR=2.012,95%CI:1.288-3.143,P<0.05),neonatal respiratory distress syndrome (aOR=l.584,95%CI:1.007-2.492,P<0.05),invasive mechanical ventilation (aOR=2.743,95%CI:1.826-4.121,P<0.05),electrolyte disturbance (aOR=2.128,95%CI:1.092-4.149,P<0.05) and periventricular leukomalacia (aOR=2.901,95%CI:1.312-6.416,P<0.05),but not male sex (aOR=1.351,95%CI:0.917-1.991,P=0.128).The risk factors for severe IVH were gestational age <28 weeks (aOR=2.200,95%CI:1.305-3.708,P<0.05),invasive mechanical ventilation (aOR=4.714,95%CI:2.809-7.911,P<0.05) and electrolyte disturbance (aOR=2.232,95%CI:1.047 4.759,P<0.05),but not male sex (aOR=1.361,95%CI:0.823 2.252,P=0.247).Conclusions Male VLBWI and ELBWI have a higher incidence of IVH and severe IVH,but male sex is not a risk factor for IVH or severe IVH.

17.
Journal of Biomedical Engineering ; (6): 192-195, 2014.
Article in Chinese | WPRIM | ID: wpr-259671

ABSTRACT

A new type of testing system used for antithrombotic pressure circulatory equipment has been developed, which realized a new method for the calibration of pressure sensor. Multi-path control and acquisition functions are achieved by this method based on human-computer interaction testing system. The precision of pressure sensor is ob tained by polynomial fitting for each test point using linear interpolation method. The result showed that the precision test of pressure sensor could be realized easily and efficiently, using the developed testing system, and the parameters of pressure sensor could be calibrated effectively, so that it could be accurately used in the antithrombotic pressure circulatory equipment. The developed testing system has a prosperous future in the aspects of promotion and application.


Subject(s)
Humans , Algorithms , Calibration , Equipment Design , Monitoring, Physiologic , Pressure , Thrombosis , Diagnosis
18.
Chinese Journal of Applied Clinical Pediatrics ; (24): 114-119, 2014.
Article in Chinese | WPRIM | ID: wpr-733267

ABSTRACT

Objective To analyze the influencing factors for intraventricular hemorrhage in the very low birth weight infants (VLBWI) and extremely low birth weight infants(ELBWI).Methods The clinical data of all VLBWI and ELBWI in the Second Hospital of Wenzhou Medical College from Jan.1,1999 to Dec.31,2011 were retrospectively collected.They were divided into the intraventricular hemorrhage (IVH) group and non-IVH group,which included mild and severe IVH in IVH group,and then the differences of perinatal factors were analyzed in the different groups.The severity of IVH was graded based on Papile classification,and SPSS 16.0 statistical software was used for the data processing and analysis.Results A total of 925 cases were collected,and the incidence rate of IVH was 12.6% (117/925 cases),in which the severe IVH accounted for 58.4% (66/113 cases).Factors like maternal hypertension,maternal age ≥ 30 years,gestational age,birth weight,male,small for gestational age,severe asphyxia,placental abnormalities (including placental abruption,placenta praevia,placenta adhesion,small placenta,aging of placenta),pneumonia,neonatal respiratory distress syndrome,pulmonary hemorrhage,invasive mechanical ventilation,using pulmonary surfactant (PS),chronic lung disease (CLD),necrotizing enterocolitis (NEC) were significantly different between 2 study groups (all P < 0.05).Logistic regression analysis identified that gestational age < 28 weeks (AOR 2.583 ; 95 % CI:1.357-4.916,P =0.004),maternal age ≥ 30 years (A OR 1.638 ; 95 % CI:1.061-2.530,P =0.026),invasive mechanical ventilation (AOR 2.098 ;95 % CI:1.262-3.488,P =0.004),NEC (A OR 3.064 ;95 % CI:1.391-6.750,P =0.005),using PS(AOR 1.794;95% CI:1.057-3.045,P =0.030),pulmonary hemorrhage(AOR 3.372;95% CI:1.138-9.989,P =0.028),subarachnoid hemorrhage (SAH) (AOR 4.936 ;95 % CI:1.717-14.184,P =0.003),periventricular leukomalacia(PVL) (AOR 3.157 ;95% CI:1.294-7.701,P =0.012),hypoxic-ischemic brain damage (HIBD)(AOR 3.777;95% CI:1.637-8.716,P =0.002) increased the risks of IVH.Invasive mechanical ventilation increased the risk of severe IVH(AOR 4.333 ;95% CI:1.861-10.088,P =0.001).Conclusions Anong infants with birth weight < 1 500 g,many prenatal,perinatal and postnatal factors are associated with incidence of IVH.Gestational age < 28 weeks,maternal age ≥ 30 years,invasive mechanical ventilation,NEC,exogenous PS,pulmonary hemorrhage,SAH,PVL and HIBD are risk factors for IVH.Cranial ultrasound plays a key role in the early recognition of IVH.

19.
Chinese Journal of Tissue Engineering Research ; (53): 1033-1038, 2014.
Article in Chinese | WPRIM | ID: wpr-444747

ABSTRACT

BACKGROUND:It is difficult to make an exact conclusion about the correlation between atherosclerosis and hemodynamic wal shear stress because of the complexity of the hemodynamic environment in the field of atherosclerosis research. OBJECTIVE:To analyze the relationship between characteristics of mural coronary artery hemodynamics parameters and atherosclerosis through myocardial bridge-coronary artery analog device. METHODS:Myocardial bridge-coronary artery analog device was used to simulate experiments in vitro. In the condition of keeping any related parameters unchanged, such as system temperature, the average flow rate and heart rate, we observed and recorded the changes of proximal and distal mean value and oscil atory value of shear stress of mural coronary artery by regulating the oppression level of myocardial bridge to mural coronary artery. RESULTS AND CONCLUSION:Under 0%oppression, there was no significant difference in distal and proximal mean value and oscil atory value of shear stress of mural coronary artery. Under 50%oppression, the proximal oscil atory value of shear stress was significantly larger than that in the distal end. Under 80%oppression, mean shear stress in the distal end was larger than that in the proximal end. Oscil atory value of shear stress in the proximal end was larger than that in the distal end. With increased oppression, the mean shear stress in the distal end was higher than that in the proximal end, but oscil atory value in the proximal end was higher than that in the distal end. These results indicated that the increase of the oscil atory value of the proximal shear stress of mural coronary artery is an important factor for the occurrence of atherosclerosis.

20.
Journal of Medical Biomechanics ; (6): E015-E019, 2013.
Article in Chinese | WPRIM | ID: wpr-804255

ABSTRACT

Objective To study distributions of the residual stresses on blood vessel, and to provide the biomechanical basis for the finite element research on stress changes in blood vessel. Methods The semi-inverse method was used for getting distributions of residual stresses on blood vessel and the result was compared with that from Commercial Software ABAQUS. On that basis, the interaction between the vessel and implanted stent was simulated to get the influence of residual stress on blood vessel. Results Distributions of three normal stresses on blood vessel obtained from the two methods were almost consistent. It is the residual stress that led to the change of vessel stress distributions, and the position of maximal stress was transformed from the inside to the outside of the vessel. Conclusions Assuming that the vessel has homogeneity and isotropic, both the semi-inverse method and the finite element method would get the similar residual stress distributions; significant differences existed between the stress states of vessel with or without considering residual stress. The stress at the inside of vessel was reduced obviously. Consideration of residual stress will be helpful for understanding the real stress state of vessel after stent deployment and providing references for the optimization design of stent.

SELECTION OF CITATIONS
SEARCH DETAIL