Objective:To investigate the current situation and influence factors of prehospital thrombolysis treatment for ST segment elevation myocardial infarction (STEMI) in China, to analyze the main factors affecting prehospital thrombolysis implementation, and optimize the pre-hospital thrombolysis strategy for STEMI to reduce mortality.Methods:A multicenter cross-sectional survey was conducted. 21 cities from six major geographical regions in China were selected by using convenient sampling method. An anonymous online electronic questionnaire was used to investigate the current situation and influence factors of prehospital emergency physicians and grassroots physicians implementing prehospital thrombolysis treatment for STEMI patients. Chi-square test was used to analyze the differences in count data between groups, and multivariate logistic regression was used to analyze the factors affecting prehospital thrombolysis in STEMI.Results:A total of 5 163 prehospital emergency physicians and physicians from grassroots township health centers/community health service centers or village clinics participated in this survey. Among them, 3208 (62.13%) have never implemtent thrombolysis, and 1 955 (37.87%) have did it before. The results of the multivariate logistic regression analysis indicated that physicians with 5-10 years of experience ( OR=1.41, 95% CI: 1.18-1.69, P<0.01), 11-20 years of experience ( OR=1.25, 95% CI: 1.03-1.52, P=0.02), those working in village clinics ( OR=1.30, 95% CI: 1.05-1.61, P=0.02), those in pre-hospital emergency medical institutions/departments ( OR=3.19, 95% CI: 2.80-3.64, P<0.01), those whose units are equipped with remote ECG transmission capabilities ( OR=1.72, 95% CI: 1.50-1.96, P<0.01), or ECG AI-assisted diagnostic tools ( OR=1.31, 95% CI: 1.15-1.49, P<0.01), and those who believe that thrombolysis is highly effective and should be widely adopted ( OR=2.55, 95% CI: 2.09-3.12, P<0.01) or consider it somewhat effective but warranting caution ( OR=2.11, 95% CI: 1.73-2.59, P<0.001), were more likely to make pre-hospital thrombolysis decisions for STEMI patients. To improve the current situation of pre-hospital thrombolysis for STEMI, the top four measures prioritized by pre-hospital emergency and grassroots physicians were enhancing the rescue capabilities of primary care doctors (92.22%), strengthening guidance from higherlevel hospitals (84.99%), increasing support for information technology (83.37%), and improving public health education (74.75%). Conclusions:The implementation rate of prehospital thrombolysis for STEMI in China still needs to be improved. Optimizing the prehospital thrombolysis strategy for STEMI, strengthening the allocation of basic medical resources and information technology support, and improving the referral mechanism are conducive to the implementation of prehospital thrombolysis for STEMI.

Polyetheretherketone (PEEK) as a new type of thermoplastic engineering plastic, has good biological activity, elastic modulus close to human cortical bone and radiation permeability, and has been widely used in medical field. This study aims to explore the safety and clinical efficacy of using 3D printing personalized PEEK materials to repaire scapular bone defects after bone tumor resection. A total of 6 patients who underwent the implantation of 3D printed PEEK scapular prosthesis from January 2020 to December 2021 in Yunnan Cancer Hospital were retrospectively analyzed. There were 3 males and 3 females, with age ranged from 14 to 52 years. There were 1 case of synovial sarcoma, 1 of Ewing's sarcoma, and 4 of chondrosarcoma. PEEK prosthesis was designed and fabricated based on CT data before surgery. Tumor resection and prosthesis replacement were performed under the premise of ensuring safe surgical boundaries, including 2 cases of total scapular prosthesis replacement and 4 cases of partial scapular prosthesis replacement. The operation time was 90-170 min, and the intraoperative blood loss was 100-400 ml. All 6 patients received satisfactory follow-up, with a tumor progression free survival time of 16-28 months. No tumor recurrence or metastasis was observed, and all patients survived tumor free. At last follow-up, the Constant-Murley shoulder joint score was a minimum of 62 points and a maximum of 68 points. The Japanese Orthopaedic Association's shoulder joint score was 63 points minimum and 78 points maximum. Computer-aided design 3D printing PEEK material prosthesis has certain advantages in the treatment of scapular tumor limb salvage. It has light weight, well adapted, relatively simple installation, good histocompatibility, and can obtain a better appearance and function of the shoulder joint after operation. It can become one of the options for limb salvage treatment of scapular tumor.

Objective: To explore the effect of RW splints on the position and occlusal relationship of classⅡ malocclusion patients with temporomandibular disorder (TMD) to provide a basis for the diagnosis and design of this kind of patient. Methods : Fifteen patients with class Ⅱ malocclusions with TMD were enrolled in this study. After 8 months of RW-splint treatment, the changes in jaw position (∠ANB, SN-MP, ∠S-G0/N-Me) and occlusal relationship (molar, cuspid teeth displacement and anterior overbite/overjet value) were recorded by a condylar displacement measuring instrument at the CR position and CO position. Results: After RW-splint treatment, the mean values of ∠ANB (t=4.971, P=0.001) and ∠SN-MP (t=9.895, P ＜ 0.01) were increased in all 15 patients, and the mean value of S-G0/N-Me (t=5.342, P=0.005) was decreased. The mean values of the distal movement of the first molars on the left and right sides of the mandible were (1.57 ± 0.79) mm and (1.69 ± 1.29) mm, respectively; the mean values of the distal movement of the canines on the left and right sides of the mandible were (1.54 ± 0.50) mm and (1.51 ± 1.08) mm, respectively; and the mean values of the overbite were (1.16 ± 0.60) mm and (1.99 ± 0.85) mm, respectively. Conclusion After RW-splint treatment, the jaw rotates clockwise, and the relationship between the molars and canines changes obviously in class Ⅱ patients with TMD, which provides a reference for the diagnosis and treatment plan of this kind of patient.

To observe the efficacy and safety of apatinib in the treatment of advanced bone and soft tissue sarcoma, and to analyze the possible related factors affecting the progression-free survival (PFS) of patients. Methods: Twenty-one patients with ad-vanced bone and soft tissue sarcoma admitted to the Department of Orthopaedics, Yunnan Cancer Hospital from June 2017 to Sep-tember 2018, were treated with apatinib tablets. The main efficacy index was progression free survival (PFS), and the secondary effica-cy index was overall survival (OS). Clinical efficacy was evaluated according to response evaluation criteria in solid tumors (RECIST) 1.1, and overall response rate (ORR), disease control rate (DCR), and safety were olserved according to the National Cancer Institute (NCI) 4.0 standard. Results: All of the 21 patients were followed up. At the last follow-up time point, March 31st, 2019, there were no CR, 2 patients (9.5%) with PR, 7 patients with SD (33.3%), and 12 patients with PD (57.1%). The ORR was 9.5%, the DCR was 42.8%, the medi-an PFS was 8 months, and the median OS was 14 months. The patient's gender, age, ECOG score, tissue source, surgery, or chemother-apy had no statistically significant effect on PFS (P>0.05). Only the history of radiotherapy before taking apatinib was a factor for pa-tients with PFS. The effect was statistically significant (P<0.05), and patients with a history of radiotherapy had a lower PFS than pa-tients without a history of radiotherapy. The adverse reactions of gradeⅢand above had hand-foot syndrome (14.3%), pneumotho-rax (14.3%) and anemia (4.8%). Conclusions: Apatinib has a certain effect for advanced bone and soft tissue sarcoma. The adverse re-actions are generally predictable, controllable and reversible. Apatinib can be a choice for patients with advanced bone and soft tissue sarcoma with good treatment adherence and no other treatment options.

Objective: To summarize the measures and experience of treatment in mass extremely severe burn patients. Methods: The clinical data and treatment of 8 extremely severe burn patients in August 2 Kunshan factory aluminum dust explosion accident who were admitted in the 100th Hospital of PLA on August 2nd, 2014, were retrospectively analyzed. There were 4 males and 4 females, aging 22-45 (34±7) years, with total burn area of 55%-98% [(89±15)%] total body surface area (TBSA) and full-thickness burn area of 45%-97% [(80±21)%] TBSA. All the 8 patients were accompanied with severe shock, inhalation injury, and blast injury. According to the requirements of former PLA General Logistics Department and Nanjing Military Command, a treatment team was set up including a special medical unit and a special care unit, with Chai Jiake from the First Affiliated Hospital of PLA General Hospital as the team leader, Zheng Qingyi from the 175th Hospital of PLA (the Affiliated Dongnan Hospital of Xiamen University) as the deputy leader, the 100th Hospital of PLA as the treatment base, and burn care, respiratory, nephrology, nursing specialists from the First Affiliated Hospital of PLA General Hospital, and the burn care experts and nursing staff from the 180th Hospital of PLA, 118th Hospital of PLA, 98th Hospital of PLA, and 175th Hospital of PLA, and nurses from the 85th Hospital of PLA, 455th Hospital of PLA, 101th Hospital of PLA, 113th Hospital of PLA as team members. Treatment strategies were adopted as unified coordination by the superior, unified responsibility of team leader, division of labor and cooperation between team members, and multidisciplinary cooperation led by department of burns. With exception of one patient who received deep vein catheterization before admission, the other 7 patients were treated with deep vein catheterization 0.5 to 3.0 hours after admission to correct hypovolemic shock as soon as possible. Eight patients received tracheotomy, and 7 patients were treated with mechanical ventilation by ventilator in protective ventilation strategy with low tide volume and low volume pressure to assist breathing. Fiberoptic bronchoscopy was done one to three times for all the 8 patients to confirm airway injuries and healing status. Escharectomy and Meek dermatoplasty in the extremities of all the 8 patients were performed 3 to 6 days after injury for the first time. Escharectomy, microskin grafting, and covering of large pieces of allogeneic skin on the trunks of 4 patients were performed 11 to 16 days after injury for the second time. The broad-spectrum antibiotics were uniformly used at first time of anti-infective therapy, and then the antibiotics species were adjusted in time. The balance of internal environment was maintained and the visceral functions were protected. One special care unit was on responsibility of only one patient. Psychological intervention was performed on admission. The rehabilitative treatment was started at early stage and in company with the whole treatment. Results: Acute renal injury occurred in 5 patients within 36 hours after injury and their renal function was restored to normal 4 days after injury due to active adjustment of fluid resuscitation program. No pulmonary complications, such as severe pulmonary infection and ventilator-associated pneumonia, occurred in the survived patients. One of the 8 patients died, and the other 7 patients were cured successfully. The wounds were basically healed in 2 patients in 26 or 27 days by 2 or 3 times of operation, and in 5 patients by 4 or 5 times of operation. The basic wound healing time was 26-64 (48±15) days for all the 7 patients. Conclusions Treatment strategies of unified coordination by the superior, unified responsibility of team leader, division of labor and cooperation between team members, and multidisciplinary cooperation led by department of burns are the bases to successful treatment. Correcting shock as soon as possible is the prerequisite and closing wound as soon as possible is the key to successful treatment. Comprehensive treatment measures, such as maintaining and regulating the function of viscera, improving the body immunity, and preventing and treating the complications, are the important components to successful treatment. It is emphasized that in the treatment of mass extremely severe burn patients, specialist burn treatment should always be in the dominant position, and other related disciplines may play a part in auxiliary function.

Objective: To explore experience of wound treatment of extremely severe mass burn patients involved in August 2nd Kunshan factory aluminum dust explosion accident. Methods: On August 2nd, 2014, 98 extremely severe burn mass patients involved in August 2nd Kunshan factory aluminum dust explosion accident were admitted to 20 hospitals in China. The patients with complete medical record were enrolled in the study and divided into microskin graft group with 56 patients and Meek skin graft group with 42 patients. Split-thickness skin in area of residual skin were resected to repair wounds of patients in microskin graft group and Meek skin graft group by microskin grafting and Meek miniature skin grafting, respectively. The residual wound size on 28 days post injury and wound infection after skin grafting of patients in the two groups, and position of donor site of all patients were retrospectively analyzed. Data were processed with t test and chi-square test. Results: The size of residual wound of patients in Meek skin graft group on 28 days post injury was (59±13)% total body surface area (TBSA), which was obviously smaller than that in microskin graft group [(70±14)%TBSA, t=4.379, P<0.05]. Twenty-nine patients in microskin graft group and 11 patients in Meek skin graft group suffered from obvious wound infection after skin grafting. Wounds of patients in two groups were repaired with residual skin around wound in head, trunk, groin, armpit, and uncommon donor sites of scrotum (4 patients), vola (10 patients), and toe or finger web (8 patients). Conclusions Meek skin graft is the first choice for wound repair of extremely severe burn mass patients, with faster wound healing, less wound infection. Uncommon donor sites of scrotum, vola, and toe or finger web can also be used for wound repair in case of lack of skin.

ObjectiveTo evaluate temporary balloon occlusion of the abdominal aorta in high-order position sacral tumor surgical operation as a useful adjuvant technique.MethodsReviewed 79 cases of patients from 2005 to 2015 treated in our department and the diagnosis of high-order position sacral tumor. Temporary balloon occlusion of abdominal aorta was used in 50 patients(male 29,female 21)during the sacral tumors surgical operations. The other 29 patients(male 18,female 11)with sacral tumors who received the non-temporary balloon occlusion therapy were used as control group. The statistical differences of the whole surgery time,the blood loss during the surgery,the happening of the postoperative deep vein thrombosis,the time of the postoperative extubation were analyzed. ResultsThe differences were statistically significant(P<0.001)in the whole surgery time of balloon occlusion group(146.36±29.38)min vs non-balloon occlusion group(206.03±125.93)min,the blood loss of balloon occlusion group(1610.70±491.14)ml vs non-balloon occlusion group(2658.62±562.213)mL, and the time of the postoperative extubation of balloon occlusion group(6.60±2.76)d vs non-balloon occlusion group(12.52±2.86)d. However,there was not significant difference of the happening of the postoperative deep vein thrombosis between balloon occlusion group and non- balloon occlusion group. ConclusionTemporary balloon occlusion of abdominal aorta is effective and reliable. It significantly reduced the time of operations,the loss of blood,mean days in hospital,effusion of post-operation and recurrence rate. It makes the operation of sacral tumors much more safer than before and is a technique worthy of popularizing.

Objective To study the expressions of hypoxia inducible factor (HIF)-1 and angiopoietin (Ang)-2 in repeated gastrointestinal bleeding due to vascular malformation, and the efficacy of treatment with thalidomide. Methods Twenty-five patients with repeated gastrointestinal bleeding due to vascular malformation confirmed by capsule endoscopy or enteroscopy were collected and 18 subjects without severe diseases were served as controls. Ten patients with gastrointestinal vascular malformation, who received 25 mg of thalidomide 4 times daily for 4 months and were followed up for at least one year, were also enrolled. The serum samples from all participauts were detected for expressions of HIF-1 and Ang-2 using enzyme-linked immunosorbent assay (ELISA).The expressions of HIF-1 and Ang-2 were compared between angiodysplasia group and control group.The expressions of HIF-1 and Ang-2 were comparatively evaluated before and after treatment with thalidomide in treatment group. Results The expressions of HIF-1 and Ang-2 in vascular malformation group [( 113. 84 ± 26. 66 ) ng/ml and ( 652. 11 ± 140. 39) ng/ml, respectively] were significantly higher than that of control group [(43.28±17.30) ng/ml and (265.60±53.88) ng/ml,respectively, P=0. 000]. The expression of HIF-1 was positively associated with that of Ang-2. (r=0. 700, P= 0. 000). There was no difference in expressions of HIF-1 and Ang-2 before and after treatment with thalidomide (P=0. 498 and =0. 136, respectively). However, significant reduction of Ang-2 [(113. 80±73. 60) ng/ml(P=0. 003)] was found in 8 effectively treated patients after thalidomide treatment. Conclusions HIF-1 and Ang-2 might play an important role in the formation of vascular malformation. The extent of Ang-2 reduction after thalidomide treatment may be helpful in evaluating its efficacy or prognosis.

Objective To evaluate the therapeutic effect of endoscopic cryotherapy for Barrett's esophagus (BE). Methods A total of 22 consecutive patients, who were diagnosed as BE from January 2008 to May 2009, underwent endoscopic cryotherapy by using pressurized gas of C02. The data including effective rate, therapy courses and procedure related complications were retrospectively analyzed.Results Except for 2 cases of withdrawal, the other 20 patients completed the treatment with a total therapy number of 42 times (mean 2. 1 times/patient) and were followed up for 6 months. Complete histologic reversal of BE mucus was achieved in all 20 patients after 1-3 times of cryotherapy, among whom complete endoscopic reversal was obtained in 9 and effective endoscopic reversal in 11. Histologic recurrence was observed in 3 cases during the follow-up, including 2 of occult intestinal metaplasia and 1 of mild intestinal metaplasia, which achieved a BE mucosal reversal rate of 85% (17/20). Procedure related complications included 1 case of esophageal ulcer and 3 cases of mild or severe esophagitis, which were all cured after acid suppression treatment. Conclusion Endoscopic cryotherapy in BE is effective and safe, with the advantages of easy manipulation, less complications and good compliances.

Objective To investigate the mechanism and effect of thalidomide on gastrointestinal bleeding of angiodysplasia. Methods The endothelial cells of human umbilical vein were cultured in vitro to exponential phase of growth, then were divided into blank control, solvent control and different concentrations (10- 100 μg/ml) of thalidomide incubated with or without basic fibroblast growth factor (bFGF). The cell proliferation was measured by MTT assay 72 h after stimulation. The expressions of vascular endothelial growth factor (VEGF) and tumor necrosis factor-α (TNF-α) were detected by ELISA and real-time PCR, respectively. Results The proliferation of endothelial cells of human umbilical vein was inhibited by thalidomide (≥40 μg/ml) both in presence or absence of bFGF. The expression of VEGF could be inhibited by 20 μg/ml of thalidomide in the absence of bFGF and 10 μg/ml in the presence of hFGF. No expression of TNF-α was detected. Conclusions The in vitro study reveals that thalidomide can inhibit the proliferation and the expression of VEGF, which may treat gastrointestinal bleeding of angiodysplasia by suppressing the angiogenesis.