Objective To find a new culture system to induce proliferation and osteodifferentiation of marrow stromal cells (MSCs) in vitro for bone tissueeng ineering． Methods There were four groups in this experiment to study effects of Passage 3 osteoblasts derived from the rat cranium and the osteogenic inductor (1 nmol/L dexamethasone，10 mmol/L beta-glycero-phosphate，50 μg/ml retin oic acid) on growth of MSCs isolated from the rat femur and the tibia． MSCs were cultured in the DMEM medium (the c ontrol group) and in the osteoinductive culture medium (the inductor group)；fur thermore, MSCs were co-cultured with the osteoblasts in the DMEM medium (the osteoblast group) and in the osteoinductive culture medium (the combined treatment group)．The cells in the four groups were counted every 2 days for 8 days and alkaline phosphatase (ALP) activity of MSCs at 10 days of cultivation was measured．The MRNA expression of osteocalcin (OC) of MSCs at 2 weeks was assayed with the reverse transcript polymase chain reaction (RT-PCR)． Results There were more cells in the osteoblast group than in the control group(31.73±3.31×104 V S. 24.33±3.04×104, Plt;0.05), but there were fewer cells in the inductor gro up(16.23±2.44×104, Plt;0.05). There was no significant difference in th e cell number between the combined treatment group (21.54±2.29×104) and th e control group（Pgt;0.05）．The ALP activity was higher in the combined trea tment group （2.01±0.56 U）than in the control group (1.27±0.43 U), in the inductor group（1.27±0.43 U）, and in the osteoblast group （0.77±0.19 U）.The osteocalcin mRNA was expressed in the three treat ment groups but was not expressed in the control group. The significantly higher leve l of the osteocalcin mRNA was expressed in the inductor group（0.783±0.094）and in the combined treatment group（0.814±0.071）than in the osteoblast group（0.302±0.026） (Plt;0.05). Conclusion The combined use of t he osteoblast and the inductor can induce marrow stromal cells. Their combined u se does not affect the normal proliferation but can obviously promote the osteodifferentiation of marrow stromal cells. This combined use can become a new culture system of the seed cells for bone tissue engineering．
目的:对腰动静脉的位置分布及变异进行描述和统计分析,以提高腰骶段脊柱手术手术的安全性和有效性.方法:对30具尸体标本进行解剖学研究,主要观察(1)腰动静脉的数量与缺失,各节段腰动静脉发出点位置的定性描述,(2)腰动静脉左右共干与上下共干的概率以及腰动静脉的其他变异。结果: 腰动脉的数量以及位置相对固定,有5对腰动脉的一共有5例,腰动脉发出点的位置也不是完全与腰椎对应。腰动脉左右共干的占9.6%,未见上下共干。动脉中仅有65.3%的动脉有静脉伴行。腰静脉的数量变异非常大,最少一侧仅有1支腰静脉,最多有5支,最常见的情况是3支,占36.7%。腰静脉的位置变异也较大,与椎体没有特别的规律。腰静脉的左右共干的概率要大于动脉,为38.5%,而上下共干也是腰静脉的独有的现象,总共有26支,占总数的12.5%。另外,腰静脉的其他变异多见。结论:当脊柱手术选择腹主动脉左侧入路或者腹主动脉下腔静脉之间入路时,腰动脉和腰静脉的解剖特点尤为重要。动脉的位置相对较恒定,而静脉则变异较大,缺失常见,左右共干,上下共干,静脉之间的大的交通支常见,与腰椎的对应性不如动脉,且其与动脉并非严格伴行,这些原因都造成了静脉容易损伤的原因,在手术中应该特别注意。
In this paper, a new surface electromyography (sEMG) signal decomposition method based on spatial location is proposed for the high-density sEMG signals in dynamic muscle contraction. Firstly, according to the waveform correlation of each muscle motor units (MU) in each channel, the firing times are extracted, and then the firing times are classified by the spatial location of MU. The MU firing trains are finally obtained. The simulation results show that the accuracy rate of a single MU firing train after classification is more than 91.67%. For real sEMG signals, the accuracy rate to find a same MU by the “two source” method is over (88.3 ± 2.1)%. This paper provides a new idea for dynamic sEMG signal decomposition.
Objective To compare the cl inical effects of indirect decompression versus open decompression to vertebral canal in treatment of thoracolumbar burst fractures without neurologic deficit. Methods From April 2004 to June 2008, 52 cases of thoracolumbar burst fracture without neurologic deficit underwent posterior exposition, reduction and fixation with Atlas Fixator (AF) instrumentation. There were 34 males and 18 females with an average age of 43.1 years (range, 31-63 years). The affectd locations were T11 in 5 cases, T12 in 24 cases, L1 in 16 cases, and L2 in 7 cases. The time from injury to operation was 3-8 days (4.4 days on average). All cases were devided into indirect decompression group (group A) and open decompression group (group B). There were no statistically significant differences (P gt; 0.05) in sex, age, affect site, and disease course between two groups. The operative time, blood loss were recoded. Preoperatively, immediately postoperstively and at last follow-up, the height of the fracture vertebra and the Cobb angle were obtained from X-ray pictures and were statistically analysed. Radiographic parameters on computed tomography (CT) pictures were used to get the encroachment rate of vertebral canal. Results The operative time was (87.3 ± 7.9) minutes and (125.3 ± 13.6) minutes, and the blood loss was (273.7 ± 23.4) mL and (512.6 ± 37.7) mL in groups A and B, respectively; showing statistically significant differences (P lt; 0.05). The average follow-up time was 17.4 months (range, 11-31 months) in group A and 19.9 months (range, 12-33 months) in group B. All wounds achieved primary heal ing postoperatively without deaths and spinal cord injuries. Postoperative compl ications in group B included 3 cases of screws loosening, 1 case of screw breakage, and 3 cases of low back pain, and were given symptomatic management. There were no statistically significant differences (P gt; 0.05) in the height of the fracture vertebra, the Cobb angle andthe encroachment rate of vertebral canal preoperatively or postoperstively between two groups. There were statistically significant differences (P lt; 0.05) in the above three parameters between preoperation and postoperation in two groups, but there were no statistically significant differences (P gt; 0.05) in the spinal correction between two groups. The losing-rate of spinal correction of the height of the fracture vertebra and the Cobb angle of group A was lower than group B, showing statistically significant differences (P lt; 0.05). Conclusion The short-term results of two decompression styles in treatment of thoracolumbar burst fractures without neurologic deficit were satisfactory, but indirect decompression has more merits than open decompression: shorter operative time, less blood loss, lower losing-rate of spinal correction, and better stabil ization of vertebral column.
Early screening is an important means to reduce breast cancer mortality. In order to solve the problem of low breast cancer screening rates caused by limited medical resources in remote and impoverished areas, this paper designs a breast cancer screening system aided with portable ultrasound Clarius. The system automatically segments the tumor area of the B-ultrasound image on the mobile terminal and uses the ultrasound radio frequency data on the cloud server to automatically classify the benign and malignant tumors. Experimental results in this study show that the accuracy of breast tumor segmentation reaches 98%, and the accuracy of benign and malignant classification reaches 82%, and the system is accurate and reliable. The system is easy to set up and operate, which is convenient for patients in remote and poor areas to carry out early breast cancer screening. It is beneficial to objectively diagnose disease, and it is the first time for the domestic breast cancer auxiliary screening system on the mobile terminal.
Pulmonary arterial hypertension (PAH) is a severe, progressive disease leading to right ventricular failure and finally death. Lung transplantation is recommended for PAH patients who do not respond to targeted drug combination therapy or World Health Organization functional class (WHO FC) Ⅲ or Ⅳ. However, only 3% of PAH patients can recieve the lung transplantation. A novel implantable interatrial shunt device (ISD) can create a relatively fixed right-to-left shunt established by balloon atrial septostomy (BAS). The device may decompress the right sided chambers, facilitate left heart filling, improve organ perfusion and reduce the likelihood of syncope, acute pulmonary hypertensive crisis and death. The systemic oxygen transport improves despite hypoxemia. Implantation is simple, feasible and safe, and the X-ray time and operation time are short. There is no severe complication or thrombosis during the mid-term follow-up of the clinical studies and the device remained patent. The syncope symptoms, six-minute walk distance, cardiac index and systemic oxygen transport improve significantly in the patients. ISD may be currently the last alternative treatment to improve symptoms and prolong survival in currently drug-resistant patients with severe PAH.
ObjectiveTo evaluate the effectiveness and safety of tranexamic acid (TXA) combined with intraoperative controlled hypotension (ICH) for reducing perioperative blood loss in primary total hip arthroplasty (THA).MethodsThe clinical data of 832 patients with initial THA due to osteonecrosis of femoral head between January 2017 and July 2020 were retrospectively analyzed. All patients received TXA treatment, and 439 patients (hypotension group) received ICH treatment with an intraoperative mean arterial pressure (MAP) below 80 mm Hg (1 mm Hg=0.133 kPa) while 393 patients (normotension group) received standard general anesthesia with no special invention on blood pressure. There was no significant difference in age, gender, body mass index, American Society of Anesthesiologists (ASA) classification, basic arterial pressure, hip range of motion, internal diseases, preoperative hemoglobin (HB) and hematocrit (HCT), coagulation function, surgical approach, and TXA dosage between the two groups (P>0.05). The perioperative blood loss and blood transfusion, anesthesia and operation time, hospitalization stay, postoperative range of motion, and complications were recorded and compared between the two groups. The patients were further divided into MAP<70 mm Hg group (group A), MAP 70-80 mm Hg group (group B), and normotension group (group C). The perioperative blood loss and postoperative complications were further analyzed to screen the best range of blood pressure.ResultsThe intraoperative MAP, total blood loss, dominant blood loss, recessive blood loss, blood transfusion rate and blood transfusion volume, anesthesia time, operation time, and hospitalizarion stay in the hypotension group were significantly lower than those in the normotension group (P<0.05). The postoperative hip flexion range of motion in the hypotension group was significantly better than that of the normotension group (Z=2.743, P=0.006), but there was no significant difference in the abduction range of motion between the two groups (Z=0.338, P=0.735). In terms of postoperative complications, the incidence of postoperative hypotension in the hypotension group was significantly higher than that in the normotension group (χ2=6.096, P=0.014), and there was no significant difference in the incidence of other complications (P>0.05). There was no stroke, pulmonary embolism, or deep vein thrombosis in the two groups, and no patients died during hospitalization. Subgroup analysis showed that there was no significant difference in total blood loss, dominant blood loss, and recessive blood loss in groups A and B during the perioperative period (P>0.05), which were significantly lower than those in group C (P<0.05). There was no significant difference in blood transfusion rate, blood transfusion volume, and incidence of acute myocardial injury between 3 groups (P>0.05); the incidence of acute kidney injury in group A was significantly higher than that in group B, and the incidence of postoperative hypotension in group A was significantly higher than that in groups B and C (P<0.05), but no significant difference was found between groups B and C (P>0.05).ConclusionThe combination of TXA and ICH has a synergistic effect. Controlling the intraoperative MAP at 70-80 mm Hg can effectively reduce the perioperative blood loss during the initial THA, and it is not accompanied by postoperative complications.