摘要:目的:研究老年患者動脈彈性功能與圍術期血壓變化的關系。方法:隨機選擇68例ASA分級Ⅰ－Ⅱ級行全麻手術的老年患者,根據檢查所得動脈彈性的結果分為四組,分別是A組(C1、C2均正常),B組(C1異常,C2正常),C組(C1正常,C2異常),D組(C1、C2均異常)。測量其術前血壓及全麻誘導8分鐘后的血壓水平。結果:〓動脈彈性功能不良的患者其術前MAP較高,且全麻誘導以后血壓波動的比例較大。結論:高血壓病的老年患者動脈彈性功能普遍降低;動脈彈性下降的老年病人全麻誘導后血壓波動較大。Abstract: Objective:To investigate the relationship between the function of arterial elasticity and BP changes during perioperation in senile patients.Methods: 68 senile patients ASA class Ⅰor Ⅱ undergoing elective surgery under general anesthestia, were divided into four groups by evaluation of arterial elasticity (C1 was for large arterial elastic index and C2 for small. C1 and C2 were normal in group A, only C2 normal in group B, only C1 normal in group C, neither was normal in group D). Arterial blood pressure (BP) before operation and 8 min after induction were monitored and recorded. Results: Patients with dysfunction of arterial elasticity presented higher MAP during preoperation and significant BP changes after induction. Conclusion: Hypertension plays a key role in arterial elasticity.Arterial Blood Pressure of the senile patients with decreased arterial elasticity changes significantly after general anesthesia induction.
In the present study, swine thighbone samples with different water contents were prepared through process of dehydration. The influence of water content on the biotribological behavior of the bone tissue was studied with nanoindentation test, reciprocating sliding test and impact wear test. It is shown that the water contents had significant influence on the mechanical properties and biotribological behavior of the swine thighbone samples. In this experiment condition, with decreasing water content, the hardness and elastic modulus of the swine thighbone samples increased, while the tribological properties significantly decreased. The viscoelasticity of bone tissue decreased with decreasing water content, which mainly resulted in different wear mechanisms of the bone tissue samples under applied loading.
Signal classification is a key of brain-computer interface (BCI). In this paper, we present a new method for classifying the electroencephalogram (EEG) signals of which the features are heterogeneous. This method is called wrapped elastic net feature selection and classification. Firstly, we used the joint application of time-domain statistic, power spectral density (PSD), common spatial pattern (CSP) and autoregressive (AR) model to extract high-dimensional fused features of the preprocessed EEG signals. Then we used the wrapped method for feature selection. We fitted the logistic regression model penalized with elastic net on the training data, and obtained the parameter estimation by coordinate descent method. Then we selected best feature subset by using 10-fold cross-validation. Finally, we classified the test sample using the trained model. Data used in the experiment were the EEG data from international BCI Competition Ⅳ. The results showed that the method proposed was suitable for fused feature selection with high-dimension. For identifying EEG signals, it is more effective and faster, and can single out a more relevant subset to obtain a relatively simple model. The average test accuracy reached 81.78%.
The mechanical behavior modeling of human soft biological tissues is a key issue for a large number of medical applications, such as surgery simulation, surgery planning, diagnosis, etc. To develop a biomechanical model of human soft tissues under large deformation for surgery simulation, the adaptive quasi-linear viscoelastic (AQLV) model was proposed and applied in human forearm soft tissues by indentation tests. An incremental ramp-and-hold test was carried out to calibrate the model parameters. To verify the predictive ability of the AQLV model, the incremental ramp-and-hold test, a single large amplitude ramp-and-hold test and a sinusoidal cyclic test at large strain amplitude were adopted in this study. Results showed that the AQLV model could predict the test results under the three kinds of load conditions. It is concluded that the AQLV model is feasible to describe the nonlinear viscoelastic properties of in vivo soft tissues under large deformation. It is promising that this model can be selected as one of the soft tissues models in the software design for surgery simulation or diagnosis.
Objective To re-estimate price elasticity of different income groups’ demand for cigarette in terms of the lastest national tobacco consumption data and provide policy-makers with evidence to make decision on public policy of tobacco control. Methods A total of 16 056 adults of different income were surveyed in 27 provinces in 2002 and the data analyzed by using two-part model (logistic and log-linear model). Results We found that the demand elasticities were -0.589, -0.234, -0.017 and 0.247 for the poor group, low income group, middle income group and high income group, respectively. Conclusions Increasing tobacco tax will result in decreasing more cigarette consumption of lower income groups than higher groups, bearing more taxation of higher income groups than lower income groups, therefore tobacco taxation is not regressive.
ObjectiveTo explore the effectiveness difference between titanium elastic intramedullary nail internal fixation and bone plate internal fixation in the treatment of adult Galeazzi fracture.MethodsNinety-seven patients of Galeazzi fracture according with the selection criteria were divided into 2 groups by prospective cohort study, who were admitted between January 2012 and November 2015. In the patients, 59 were treated with open reduction and bone plate internal fixation (plate group), and 38 with titanium elastic intramedullary nail internal fixation (minimally invasive group). There was no significant difference in the gender, age, cause of injury, fracture site, type of fracture, and time from injury to operation between 2 groups (P>0.05). The operation time, intraoperative blood loss, fracture healing time, and complications were recorded and compared between 2 groups, and the forearm function was evaluated by Anderson score.ResultsAll the patients were followed up 12-23 months (mean, 17 months). The operation time, intraoperative blood loss, fracture healing time of minimally invasive group were significantly less than those in plate group (P<0.05). There were 1 case of fracture nonunion, 1 case of wound infection in plate group, and 1 case of nail tail slight infection in minimally invasive group, which were all cured after the corresponding treatment. The remaining patients had good fracture healing, and no vascular injury, internal fixation failure, deep infection, or other complications occurred. According to Anderson score at 12 months after operation, the forearm function results were excellent in 46 cases, good in 12 cases, and poor in 1 case, with an excellent and good rate of 98.3% in plate group; and the results were excellent in 26 cases, good in 11 cases, and poor in 1 case, with an excellent and good rate of 97.4% in minimally invasive group; showing no significant difference (χ2=0.10, P=0.75).ConclusionMinimally invasive fixation with titanium elastic nail has such advantages as small damage, quick recovery, no skin scarring, etc. As long as the correct indication is selected, minimally invasive titanium intramedullary nail internal fixation of Galeazzi fractures can also get good effectiveness.
Alveolar bone reconstruction simulation is an effective means for quantifying orthodontics, but currently, it is not possible to directly obtain human alveolar bone material models for simulation. This study introduces a prediction method for the equivalent shear modulus of three-dimensional random porous materials, integrating the first-order Ogden hyperelastic model to construct a computed tomography (CT) based porous hyperelastic Ogden model (CT-PHO) for human alveolar bone. Model parameters are derived by combining results from micro-CT, nanoindentation experiments, and uniaxial compression tests. Compared to previous predictive models, the CT-PHO model shows a lower root mean square error (RMSE) under all bone density conditions. Simulation results using the CT-PHO model parameters in uniaxial compression experiments demonstrate more accurate prediction of the mechanical behavior of alveolar bone under compression. Further prediction and validation with different individual human alveolar bone samples yield accurate results, confirming the generality of the CT-PHO model. The study suggests that the CT-PHO model proposed in this paper can estimate the material properties of human alveolar bone and may eventually be used for bone reconstruction simulations to guide clinical treatment.
Objective To compare the effectiveness of titanium elastic nail (TEN) and locking compression plate fixation in treating femoral subtrochanteric fracture in older children. Methods Between April 2015 and September 2016, 35 older children (aged 7-13 years) with femoral subtrochanteric fractures were treated, the clinical data were retrospectively reviewed. TEN fixation was used in 19 cases (group A) and locking compression plate fixation in 16 cases (group B). There was no significant difference in age, gender, sides, fracture causes, type of fracture, and time from injury to operation between 2 groups (P>0.05). The fluoroscopy times, operation time, intraoperative blood loss, fracture healing time were recorded and compared between 2 groups. The limb function was evaluated according to the Sanders scores and Flynnet al. outcome score. Results All the patients were followed up 6-24 months (mean, 11.46 months). The operation time, intraoperative blood loss, and fracture healing time of group A were significantly less than those of group B, but the fluoroscopy times of group A was significantly more than that of group B (P<0.05). All the fractures were healed, no breakage of screw, infection of deep tissue, nerve injury, osteonecrosis of the femoral head, or other complication occurred. At last follow-up, according to the Sanders scores, the results were excellent in 14 cases, good in 4 cases, and fair in 1 case in group A with an excellent and good rate of 94.74%; the results were excellent in 12 cases, good in 3 cases, and fair in 1 case in group B with an excellent and good rate of 93.75%; showing no significant difference between 2 groups (χ2=0.400, P=0.980). According to the Flynn et al. outcome score, the results were excellent in 13 cases, good in 5 cases, and fair in 1 case in group A with an excellent and good rate of 94.74%; the results were excellent in 11 cases, good in 3 cases, and fair in 2 cases in group B with an excellent and good rate of 87.50%; showing no significant difference between 2 groups (χ2=0.748, P=0.688). Conclusion Both TEN and locking compression plate have satisfactory outcomes for treating pediatric femoral subtrochanteric fractures. TEN method has minimally trauma, security, and faster fracture healing when compared with locking compression plate.
This study was aimed to compare the mechanical characteristics under different physiological load conditions with three-dimensional finite element model of rigid fixation and elastic fixation in the lumbar. We observed the stress distribution characteristics of a sample of healthy male volunteer modeling under vertical, flexion and extension torque situation. The outcomes showed that there existed 4-6 times pressure on the connecting rod of rigid fixation compared with the elastic fixations under different loads, and the stress peak and area of force on elastic fixation were much higher than that of the rigid fixations. The elastic fixation has more biomechanical advantages than rigid fixation in promoting interbody lumbar fusion after surgery.
ObjectiveTo explore the clinical features and EEG features of gelastic seizures, and analyze its value of lateral localization of epileptogenic area. MethodsAll patients with gelastic seizures admitted to the Sanbo Brain Hospital of Capital Medical University between January 2014 and December 2023 were reviewed and analyzed for history, symptomatology, imaging, electroencephalographic features and surgical protocols in patients who met the inclusion criteria and were followed up for at least 1 year, and surgical efficacy was assessed by using the Engel grading. ResultsA total of 51 patients with gelastic seizures were included, there were 32 (62.75%) males and 19 (37.25%) females, 21 (41.18%) with hypothalamic hamartomas (HH) and 30 (58.82%) with non-hypothalamic hamartomas. The age of onset was earlier in the HH group than in the non-HH group, with a median age of onset of 24.00 (0.00 ~ 96.00) and 78.00 (1.00 ~ 396.00) months (P<0.001). There are three types of laughter according to their characteristics: smiling or pleasant expressions, laughing out loud, crying or bitter laughter, with smiling or pleasant expressions being the most common (49.02%). Simple laughter is rare in all patients and is often accompanied by other manifestations such as autonomic symptoms, automatic movements, complex movements, and tonic seizures. Most of the HH group started with laughter whereas in the non-HH group laughter appeared mostly in the mid to late stages (P=0.007). Most of the HH group (57.14%) had preserved consciousness whereas most of the non-HH group (83.33%) had loss of consciousness (P=0.003). The interictal discharges in the HH group were mostly diffuse or multiregional, whereas those in the non-HH group were mostly regional (P=0.035). The onset of EEG during the seizure period in the HH group was mostly diffuse, whereas those in the non-HH group were mostly regional, mainly in the frontal and temporal regions, but there was no significant difference between the two groups (P=0.148). The non-HH group was mostly seen in those with definite lesions, and the most common type of lesion was FCD (focal cortical dysplasia, FCD). All patients enrolled in the group underwent surgical treatment, and stereoelectroencephalogram (SEEG) electrode implantation was performed in 13 cases in the HH group and in 17 cases in the non-HH group. 61.90% of the patients in the HH group had an Engel grade I, and 73.33% of the patients in the non-HH group had an Engel grade I. ConclusionsGelastic seizures has a complex neural network, with common causes other than hypothalamic hamartomas, and is most commonly seen in frontal or temporal lobe epilepsy, as well as in the insula or parietal lobe, with the most common type of lesion being FCD. The symptomatology, stage of onset, and electroencephalographic features of gelastic seizures can help in the differential diagnosis, and SEEG can help define the origin of the seizure and its diffusion pathway. The overall prognosis of surgical treatment was better in both the hypothalamic hamartomas and non-hypothalamic hamartomas groups.