OBJECTIVE: To investigate the hemodynamic changes of the end-to-end anastomosed arteries with nitinol clips. METHODS: Fifteen New Zealand rabbits were divided into anastomosis clip group, suture group and control group randomly. The carotid arteries were resected and end-to-end anastomosis were carried out with nitinol clips in anastomosis clip group and with traditional suture in suture group. The carotid arteries remained undamaged in control group. On the days of 3, 9, 21 and 30 postoperatively, mean blood velocity (Vm), pulsatility index (PI) and resistance index (RI) of anastomosed arteries were determined by Ultrasonography Doppler. RESULTS: On the days of 8 and 9 postoperatively, there were no significant differences of VM, PI and RI between two experimental groups (P gt; 0.05). On the days of 20 and 30 postoperatively, the differences of Vm and RI were significant (Vm: P lt; 0.01, P lt; 0.05: RI: P lt; 0.01, P lt; 0.05). The hemodynamic restoration of the anastomosis clip group was better than that of the suture group. CONCLUSION: The hemodynamics of arteries anastomosed with nitinol clips is better than that with traditional suture. This technique has practical value clinically.
The task of automatic generation of medical image reports faces various challenges, such as diverse types of diseases and a lack of professionalism and fluency in report descriptions. To address these issues, this paper proposes a multimodal medical imaging report based on memory drive method (mMIRmd). Firstly, a hierarchical vision transformer using shifted windows (Swin-Transformer) is utilized to extract multi-perspective visual features of patient medical images, and semantic features of textual medical history information are extracted using bidirectional encoder representations from transformers (BERT). Subsequently, the visual and semantic features are integrated to enhance the model's ability to recognize different disease types. Furthermore, a medical text pre-trained word vector dictionary is employed to encode labels of visual features, thereby enhancing the professionalism of the generated reports. Finally, a memory driven module is introduced in the decoder, addressing long-distance dependencies in medical image data. This study is validated on the chest X-ray dataset collected at Indiana University (IU X-Ray) and the medical information mart for intensive care chest x-ray (MIMIC-CXR) released by the Massachusetts Institute of Technology and Massachusetts General Hospital. Experimental results indicate that the proposed method can better focus on the affected areas, improve the accuracy and fluency of report generation, and assist radiologists in quickly completing medical image report writing.
ObjectiveTo evaluate the effect of nickel-titanium three-dimensional memory alloy mesh combined with autologous bone for living model of canine tibial plateau collapse fracture by biomechanical testing. MethodsSixteen healthy 12-month-old Beagle dogs were randomly divided into 4 group, 4 dogs in each group. The dogs were used to establish the tibial plateau collapse fracture model in groups A, B, and C. Then, the nickel-titanium three-dimensional memory alloy mesh combined with autologous bone (the fibula cortical bone particles), the artificial bone (nano-hydroxyapatite), and autologous fibula cortical bone particles were implanted to repair the bone defects within 4 hours after modeling in groups A, B, and C, respectively; and the plate and screws were fixed outside the bone defects. The dogs were not treated in group D, as normal control. At 5 months after operation, all animals were sacrificed and the tibial specimens were harvested and observed visually. The destructive axial compression experiments were carried out by the biomechanical testing machine. The displacement and the maximum failure load were recorded and the axial stiffness was calculated. ResultsAll animals stayed alive after operation, and all incisions healed. After 1-3 days of operation, the animals could stand and move, and no obvious limb deformity was found. The articular surfaces of the tibial plateau specimens were completely smooth at 5 months after operation. No obvious articular surface collapse was observed. The displacement and maximum failure load of specimens in groups A and D were significantly higher than those in groups B and C (P<0.05). But no significant difference was found between groups A and D and between groups B and C (P>0.05). ConclusionThe nickel-titanium three-dimensional memory alloy mesh combined with autologous bone for subarticular bone defect of tibial plateau in dogs has good biomechanical properties at 5 months after operation, and has better axial stiffness when compared with the artificial bone and autologous bone graft.
Fixation of silicon-polyester fiber network on skull defect was usually difficult to handle and the fixation was unstable. In order to solve these problems, NiTi shape-memory alloy cramp was adopted and 101 patients with skull defects were selected for this clinical trial. Among them, there were 79 males and 22 females, and the age ranged from 12-55 years old. The area of skull defect ranged from 3 cm x 4 cm to 10 cm x 16 cm. All of these patients received repairing of the skull defects by silicon-polyester fiber network which was fixed by NiTi memory alloy cramps. After operation, there was no complication. One hundred patients were followed up for 1-8 years, in which 97 cases returned to their normal work, and only 2 cases had a transient dysfunction of frontal muscle for 2 months. In addition, There were no loosening of the cramps, displacement of plastic network and malignant degeneration. The NiTi shape-memory alloy cramps had the following advantages: 1. Simple operative procedure; 2. Rigid fixation; 3. Mild postoperative tissue reaction; 4. Few postoperative complication; 5. Favorable effect of skull repair; 6. No interference with CT and MRI image; 7. No carcinogenicity.
【Abstract】Objective To study the advances in clinical application of shape memory alloy (SMA) in general surgery. Methods The literature in the recent years on the advances of SMA was reviewed. Results At present clinical application of SMA have been developed. Different stents could dilate the benign and malignant stricture of blood vessels, biliary ducts, cola, recta and gastric outlet obstruction. The SMA catheter system was effective for peroral cholangiopancreatoscopy. Novel nitinol basket instrument might be useful for percutaneous cholecystolithotomy. Compression anastomoses was safe and sound in gastrointestinal surgery using a device made of SMA. Nitinol stent could be used in transjugular intrahepatic portosystemic stent shunt (TIPSS) with satisfactory results. Nitinol occlusion devices was superior to stainless steel coils. The Simon nitinol filter represented a new generation of venous interruption devices designed to prevent recurrent pulmonary embolism. Conclusion Clinical application of SMA will be increased by the development of endoscope, laparoscope and interventional technique.
ObjectiveTo systematically review the effect of media multitasking on working memory and attention among adolescents. MethodsCNKI, CBM, WanFang Data, VIP, PubMed, Web of Science, and EMbase databases were electronically searched to collect cross-sectional studies on the effect of media multitasking on working memory and attention among adolescents from inception to January 1st, 2021. Two reviewers independently screened literature, extracted data, and assessed the risk of bias of included studies; then, meta-analysis was performed using Stata 15.1 software. ResultsA total of 16 cross-sectional studies were included. The results of meta-analysis showed that there were negative correlations between media multitasking and working memory (Cohen's d=0.40, 95%CI 0.14 to 0.66, P＝0.003), as well as in attention (Cohen's d=1.02, 95%CI 0.58 to 1.47, P<0.001). ConclusionCurrent evidence shows that media multitasking has negative impact on working memory and attention. Due to limited quality and quantity of the included studies, more high-quality studies are required to verify the above conclusion.
Objective To investigate the biocompatibility of diamond-like carbon(DLC) coated NickelTitanium shape memory alloy with osteoblasts cultured invitro. Methods Rabbit’s osteoblasts were incubated with DLCcoated NickelTitanium shape memory alloy disks and uncoated ones of equal size for 5 days. The control group（without shape memory alloy in culture media） was performed simultaneously. The cultured cells were counted and graphed. The samples from culture media were collected and the concentrations of alkaline phosphatase (ALP) and nickel（Ni2+） were measured from the 1st to 5th day respectively. Results The proliferation of osteoblasts and the concentration of ALP in both DLC-coated group and control gruop was higher than uncoated group. The proliferation of osteoblasts on the 3rd, 4th, and 5th day in both DLC-coatedgroup and control group was significantly higher than that in the uncoated group(P＜0.05). The concentration of ALP in DLC-coated group on the 2nd, 3rd, and 5th day and in the control group on the 3rd, 4th, and 5th day was significantly higher than that in the uncoated group(P＜0.05). The concentration of Ni2+ on the 3rd, 4th, and 5th day was significantly lower than that in the uncoated group(P＜0.05). Conclusion DLC- coated NickelTitanium shape memory alloys appears to have better biocompatibility with osteoblast cultured in vitro compared to uncoated ones.
The extraction of neuroimaging features of migraine patients and the design of identification models are of great significance for the auxiliary diagnosis of related diseases. Compared with the commonly used image features, this study directly uses time-series signals to characterize the functional state of the brain in migraine patients and healthy controls, which can effectively utilize the temporal information and reduce the computational effort of classification model training. Firstly, Group Independent Component Analysis and Dictionary Learning were used to segment different brain areas for small-sample groups and then the regional average time-series signals were extracted. Next, the extracted time series were divided equally into multiple subseries to expand the model input sample. Finally, the time series were modeled using a bi-directional long-short term memory network to learn the pre-and-post temporal information within each time series to characterize the periodic brain state changes to improve the diagnostic accuracy of migraine. The results showed that the classification accuracy of migraine patients and healthy controls was 96.94%, the area under the curve was 0.98, and the computation time was relatively shorter. The experiments indicate that the method in this paper has strong applicability, and the combination of time-series feature extraction and bi-directional long-short term memory network model can be better used for the classification and diagnosis of migraine. This work provides a new idea for the lightweight diagnostic model based on small-sample neuroimaging data, and contributes to the exploration of the neural discrimination mechanism of related diseases.
目的 探讨人工髋关节置换术后Vancouver B1型股骨假体周围骨折的治疗方法。 方法 2006年4月－2011年2月采用记忆合金抓握式接骨板固定结合自体髂骨植骨治疗6例Vancouver B1型股骨假体周围骨折。其中男2例，女4例；年龄55～78岁，平均68.5岁。6例均为初次行人工关节置换术后6个月～3年，平均18.4个月发生假体周围骨折；骨折至手术时间为3～6 d，平均4.2 d。 结果 术后切口均Ⅰ期愈合，无深静脉血栓形成、肺部感染、肺栓塞等并发症发生。6例均获随访，随访时间13个月～4年，平均28.6个月。X线片示骨折全部愈合，愈合时间12～20周，平均14.8周。末次随访时Harris评分76～93分，平均83.6分；获优3例，良3例。无1例出现接骨板折断、松动，骨折再移位、骨不连、股骨假体松动等并发症。 结论 记忆合金抓握式接骨板结合自体髂骨植骨治疗Vancouver B1型股骨假体周围骨折具有固定可靠、操作简便的特点，可获满意临床疗效。