Objective To determine the median effective plasma concentration of remifentanil (EC50) inhibiting cardiovascular response to tracheal intubation and skin incision when combined with propofol in patients of Uighur nationality.Methods Thirty ASA Ⅰ or Ⅱ Uighurs aged 20-60 yr with body mass index of 18-30 kg/m2 undergoing elective laparoscopic cholecystectomy were enrolled in this study.Anesthesia was induced and maintained with propofol infusion.BIS value was maintained at 40-50.TCI of remifentanil was then started.The initial target plasma concentration (Cp) was 6.0 ng/ml.EC50 of remifentanil was determined by modified Dixon' s upand-down sequential experiment.Each time Cp increased/decreased by 0.5 ng/ml.Tracheal intubation was facili.tated with cisatracurium 0.2 mg/kg at 2 min after a new Cp was set when target effect-site concentration (Ce) was balanced with Cp.Positive cardiovascular response was defined as increase in SBP by 15％ and/or HR ＞ 90 bpm lasting＞15 s.The EC50 (95％ confidence interval) of remifentanil blunting responses to tracheal intubation and skin incision was calculated.Results EC50 (95 ％ confidence interval) of remifentanil inhibiting cardiovascular response to tracheal intubation and skin incision when combined with propofol was 3.4 (2.3-4.5) ng/ml and 3.8 (2.8-4.9) ng/ml respectively.Conclusion When depth of anesthesia was maintained at BIS value 40-50 with propofol infusion,the EC50 of remifentanil inhibiting cardiovascular response to tracheal intubation and skin incision is 3.4 and 3.8 ng/ml respectively.

Objective To analyze the clinical and MRI images of testicular teratoma in children and to compare with pathological results.Methods The clinical and MRI data of 12 children with testicular teratoma confirmed by pathology were analyzed retrospec-tively.Results Of the 12 cases,6 cases were on the left testicle and 6 cases were on the right testicle.The clinical manifestations were all painless testicle enlargement.Of these,6 cases were accompanied by a slight increase of neuron-specific enolase,3 cases had increased alpha-fetoprotein(AFP),10 cases were mature teratoma,and 2 cases were immature teratoma.MRI findings showed that the lesions in 6 cases were cystic,with long T1 and T2 signals as the main signals,no reduction in lipid pressure image signals,no enhance-ment on the enhanced scan,and low signal on diffusion weighted imaging(DWI).The other 6 cases were cystic-solid lesions,mainly with mixed T1 and T2 signals,and showed uneven high signal on DWI.The cystic components were not enhanced on the enhanced scan,and the solid components were mildly to significantly enhanced.Among them,3 cases were accompanied by irregular flaky short T1 and long T2 signals,decreased lipid pressure image signals,1 case was accompanied by speckle long T1 and short T2 signals.And the envelope intact in all 12 cases.Conclusion The MRI findings of testicular teratoma in children are mostly cystic lesions,with few signs of fat and calcification,and no obvious invasion of peripheral structures.AFP examination is helpful for diagnosis.

Objective To observe CT and MRI manifestations of lipofibromatosis(LPF)in children.Methods Data of 16 children with LPF confirmed by pathology were retrospectively analyzed,and CT and MRI manifestations of lesions were observed.Results Among 16 cases,lesions with clear boundary were found in 4 cases but with unclear boundary in 12 cases,shaped regularly in 6 cases but irregularly in 10 cases,with incomplete capsule in 2 cases but without capsule in 14 cases.Fat predominant type lesions were detected in 6 cases,mainly characterized by scattered fibrous bands in the center or cloud like soft tissue density/signal on one side of lesion,without obvious boundary.Fibrous dominant type lesions were noticed in 8 cases,mainly present as loose morphology,multiple fibrous bands extending to surrounding area,with scattered cystic fat density/signal within the lesion.Balanced type LPF lesion was observed in 2 cases,mainly manifestated as regular shape mixed density/signal lesion with clear boundary.Among 12 cases who underwent enhanced scanning,mild progressive enhancement in the non-fat area were observed in 7 cases,obvious peripheral enhancement but not obvious central enhancement was found in 2 case,obvious homogeneous enhancement was noticed in 1 case,while no obvious enhancement was found in 2 cases.No obvious calcification,cystic changes nor bone destruction was detected.Conclusion CT and MRI manifestations of LPF included subcutaneous fat containing density/signal,often composed mainly of adipocytes or fibrous components,with mild progressive enhancement or significant enhancement,without obvious capsule,calcification,cystic changes nor bone destruction.

Objective To develop electrically evoked auditory brainstem response(EABR) modules of REZ-Ⅰ domestic cochlear implant device,and testify the reliability and validity of the modules.Methods Postoperative EABR were recorded in guinea pigs by using the self-designed EABR module.Results EABR waves were recorded in all 15 ears of 9 guinea pigs with normal hearing.The threshold was (159.00 ±50.21) current level (CL) and e Ⅲ wave latency was (2.36 ± 0.46)ms of 100 μs pulse width stimulation; for 150 μs pulse width stimulation,the threshold was (131.44 ± 49.25)CL and e Ⅲ wave latency was (2.59 ± 0.46) ms ; for 200 μs pulse width stimulation,the threshold was (119.63 ± 52.56) CL and e Ⅲ wave latency was (2.62 ± 0.44) ms.Conclusion According the preliminary results of the study,the reliability and stability of the EABR modules of domestic cochlear implant device can meet the demands of EABR recording.

ObjectiveTo propose a three-degree-of-freedom model of electric wheelchair, to optimize the steering stability of the wheelchair. MethodsBased on the two degrees of freedom vehicle model and considering the influence of body inertia and lateral wind, the wheelchair roll angle was introduced to establish the three degrees of freedom steering model of wheelchair. The lateral velocity, centroid sideslip angle, yaw rate and body roll angle response of the motor angular velocity input under different working conditions were simulated and analyzed respectively. Taking KS2 electric wheelchair as an example, the wheelchair steering experiment was designed to verify the rationality and feasibility of the model, and the optimization effect of the model algorithm on the wheelchair handling and stability. ResultsThe maneuverability and stability of the electric wheelchair with three degrees of freedom model algorithm were significantly improved, and the response curve was smoother. The smaller the |V_L-V_R|/t was, the better the handling stability was when the left and right motors of the wheelchair had the same steering direction. When |V_L-V_R|/t was the same, the steering maneuverability was better on the reverse rotation of the motor, but the handling stability also decreased. ConclusionThe simulation analysis is in good agreement with the experimental results, which verifies that the model is reasonable and feasible. The model algorithm can better optimize the handling stability of electric wheelchairs, and can be generally applied to study and analyze the handling stability of different wheelchairs when they turn.

【Objective】 To investigate the feasibility of laparoscopic simple prostatectomy (LSP) in the treatment of large volume benign prostate hyperplasia (BPH). 【Methods】 Clinical and follow-up data of 30 patients with large volume BPH treated with LSP in our hospital during Feb.2019 and Dec.2021 were retrospectively analyzed. All patients underwent extraperitoneal LSP operation. The perioperative and 1-12 month postoperative follow-up data were analyzed. 【Results】 The average prostate volume was (92.4±38.9) mL, operation time (125±45) min, and weight of resected prostate (60.25±16.90) g. The hemoglobin decreased by (12.21±7.25) g/d after operation. No blood transfusion was needed. There was no need for bladder irrigation after operation in 21 cases (70%), and 9 cases (30%) had bladder irrigation time of (0.95±0.49) d. The postoperative catheter indwelling time was (6.92±2.51) d, and hospital stay (5.36±1.63) d. During the follow-up of (9.25±5.4) months, there was 1 case of postoperative intestinal obstruction (Clavien-Dindo grade II), 1 case of transient urinary incontinence (Clavien-Dindo grade I), and 1 case of delayed hematuria (Clavien-Dindo grade I). No urethral stricture occurred. The maximum urinary flow rate (Qmax), post-void residual urine volume (PVR), International Prostate Symptom Score (IPSS) and quality of life (QoL) 3 months after operation were significantly improved compared with those before operation (P<0.05). There was no significant difference in sexual function before and after operation (P>0.05). 【Conclusion】 LSP is safe and effective in the treatment of large volume BPH. It has advantages of complete resection of glands, minor bleeding and short postoperative bladder irrigation time. However, it still needs to be confirmed by a prospective control study of large samples.

Image-guided radiation therapy using magnetic resonance imaging (MRI) is a new technology that has been widely studied and developed in recent years. The technology combines the advantages of MRI imaging, and can offer online real-time tracking of tumor and adjacent organs at risk, as well as real-time optimization of radiotherapy plan. In order to provide a comprehensive understanding of this technology, and to grasp the international development and trends in this field, this paper reviews and summarizes related researches, so as to make the researchers and clinical personnel in this field to understand recent status of this technology, and carry out corresponding researches. This paper summarizes the advantages of MRI and the research progress of MRI linear accelerator (MR-Linac), online guidance, adaptive optimization, and dosimetry-related research. Possible development direction of these technologies in the future is also discussed. It is expected that this review can provide a certain reference value for clinician and related researchers to understand the research progress in the field.
Magnetic Resonance Imaging ; Particle Accelerators ; Radiometry ; Radiotherapy Planning, Computer-Assisted ; Radiotherapy, Image-Guided

During coronavirus disease 2019 epidemic, the treatment of severe trauma has been impacted. The Consensus on emergency surgery and infection prevention and control for severe trauma patients with 2019 novel corona virus pneumonia was published online on February 12, 2020, providing a strong guidance for the emergency treatment of severe trauma and the self-protection of medical staffs in the early stage of the epidemic. With the Joint Prevention and Control Mechanism of the State Council renaming "novel coronavirus pneumonia" to "novel coronavirus infection" and the infection being managed with measures against class B infectious diseases since January 8, 2023, the consensus published in 2020 is no longer applicable to the emergency treatment of severe trauma in the new stage of epidemic prevention and control. In this context, led by the Chinese Traumatology Association, Chinese Trauma Surgeon Association, Trauma Medicine Branch of Chinese International Exchange and Promotive Association for Medical and Health Care, and Editorial Board of Chinese Journal of Traumatology, the Chinese expert consensus on emergency surgery for severe trauma and infection prevention during coronavirus disease 2019 epidemic ( version 2023) is formulated to ensure the effectiveness and safety in the treatment of severe trauma in the new stage. Based on the policy of the Joint Prevention and Control Mechanism of the State Council and by using evidence-based medical evidence as well as Delphi expert consultation and voting, 16 recommendations are put forward from the four aspects of the related definitions, infection prevention, preoperative assessment and preparation, emergency operation and postoperative management, hoping to provide a reference for severe trauma care in the new stage of the epidemic prevention and control.