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81.
BACKGROUND: Tumor segment resection is one of the standard methods for the treatment of bone tumors. However, the reconstruction of bone defects atumor resection faces many challenges. A growing number of researchers are focusing on 3D-printed prostheses for bone defect repair and reconstruction following bone tumor surgery. OBJECTIVE: To explore the feasibility of 3D-printed prostheses in the reconstruction of large bone defect following bone tumor surgery and to evaluate the postoperative outcomes. METHODS: Retrospective analysis of clinical data of 24 patients [19 males and 5 females, age 23.8 (6-61) years] who underwent bone tumor resection and 3D-printed prosthesis implantation in the Department of Bone Oncology, the First Affiliated Hospital of Xinjiang Medical University from December 2020 to September 2021 was conducted. There were 7 cases with distal femur tumor, 5 with pelvis tumor, 4 with proximal tibia tumor, 3 with middle femur tumor, 1 with distal tibia tumor, 1 with proximal humerus tumor, 1 with middle humerus tumor, 1 with scapula tumor, 1 with ulna tumor, and 22 cases with primary tumors (13 osteosarcoma, 4 Ewing sarcoma, 2 giant cell tumor of bone, 1 chondroblastoma, 1 chondrosarcoma, and 1 osteoblastoma), 2 metastatic carcinoma. Preoperative and postoperative imaging data were recorded and neoadjuvant chemotherapy was administered in 17 cases before surgery. The Musculoskeletal Tumour Society score was used to assess limb function before surgery and 6 months after surgery, and pain was assessed by the Visual Analog Scale, as well as the complications were recorded. RESULTS AND CONCLUSION: (1) All patients undergoing resection of the tumor segment and 3D-printed prosthesis implantation for the reconstruction of the bone defect were followed for 6-49 months, and the results showed that the length of osteotomy was (18.2 ± 7.3) cm and an average intraoperative bleeding volume was 740 (100-3 000) mL. (2) Two patients died of systemic metastasis, the remaining 22 had no pulmonary metastasis or recurrence during the follow-up period, and 1 patient developed aseptic loosening of the prosthesis at 25 months postoperatively. (3) The Musculoskeletal Tumour Society scores were significantly increased, while Visual Analog Scale scores were significantly decreased (P < 0.05) at 6 months postoperatively. (4) The Musculoskeletal Tumor Society score was rated excellent in all 22 patients at the final follow-up. (5) These results suggest that 3D-printed prosthesis is suitable for the reconstruction of large bone defects caused by bone tumor resection. Patients have good postoperative function and few complications. However, further investigations are needed to explore long-term follow-up results. © 2023, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved.  相似文献   
82.
We report on a fetus with alobar holoprosencephaly, microphthalmia, midline cleft lip and palate, absent nose, dysplastic ears, radial defects, pentalogy of Fallot, unilateral renal aplasia, absent gallbladder, vertebral anomalies, and absence of ribs. The father had a cleft palate, bilateral colobomas of the iris and retina, a bifid uvula, vertebral anomalies, and unilateral congential hearing loss. His sister had a cleft lip. On the basis of this family and the family reported by Steinfeld [1982], this malformation syndrome can be defined as a rare autosomal dominant syndrome whose main component manifestations are holoprosencephaly, predominantly radial limb deficiency, heart defects, kidney malformations, absence of gallbladder, and vertebral anomalies. © 1993 Wiley-Liss, Inc.  相似文献   
83.
Coeliac disease is an important cause of malabsorption, particularly of folic acid, in adults. We investigated the possibility that it might be a maternal risk factor for neural tube defect (NTD)-associated pregnancy by screening affected mothers using serum endomysial antibody (EmA) which has high sensitivity and specificity for coeliac disease. One (1.6%) of 60 patients was EmA positive and had a diagnosis of coeliac disease confirmed by the finding of villous atrophy on jejunal biopsy. In conclusion, the majority of NTD-associated pregnancies are not associated with maternal coeliac disease and our study is additional evidence that abnormalities of folic acid metabolism rather than absorption are the most important risk factors for NTD. Further studies are needed to determine whether the coeliac disease prevalence among women with NTD-affected pregnancy is higher than that of the general population.  相似文献   
84.
The endocardial cushions play a critical role in septation of the four-chambered mammalian heart and in the formation of the valve leaflets that control blood flow through the heart. Within the outflow tract (OFT), both cardiac neural crest and endocardial-derived mesenchymal cells contribute to the endocardial cushions. Bone morphogenetic protein 4 (BMP4) is required for endocardial cushion development and for normal septation of the OFT. In the present study, we show that anterior heart field (AHF)-derived myocardium is an essential source of BMP4 required for normal endocardial cushion expansion and remodeling. Loss of BMP4 from the AHF in mice results in an insufficient number of cells in the developing OFT endocardial cushions, defective cushion remodeling, ventricular septal defects, persistent truncus arteriosus, and abnormal semilunar valve formation.  相似文献   
85.
Summary Substance P (SP) is known to accelerate mucociliary (m.c.) activity in the rabbit maxillary sinus in vivo. The physiological significance of this finding was investigated by testing three putative SP antagonists. [Arg5, d-Trp7, 9, Nle11]SP5–11 could not be used as an antagonist because it stimulated m.c. activity. [d-Arg1, d-Trp7, 9, Leu11]SP had no effect on the m.c. activity changes induced by SP. [d-Pro2, d-Trp7, 9]SP was found to be an effective antagonist, 1 mg/kg of this drug reversibly inhibiting both the effects of 0.1 g/kg SP and the stimulating effect of 1.0 g/kg bradykinin and 30.0g/kg capsaicin; the stimulating effect of 0.5 g/kg methacholine was not inhibited. It is suggested that bradykinin and capsaicin stimulate m.c. activity at least partly by releasing SP.The results of this investigation also support the view that the accelerating effect of SP on m.c. activity reflects physiological SP-mediated protective mechanisms in the airways. It is concluded that [d-Pro2, d-Trp7, 9]SP is a useful pharmacological tool for studying the role of SP in the control of m.c. actvity in rabbits.  相似文献   
86.
目的:报告成人室间隔缺损的外科治疗经验。方法:对26例成人室间隔缺损的手术治疗进行回顾性分析。其中行室缺直接缝合3例,单纯补片修补19例,单向活瓣补片修补4例。同时行主动脉瓣折叠悬吊2例,双瓣置换l例,二尖瓣成成形l例,三尖瓣成形4例.结果:无手术死亡。术后并发症:切口感染、术后出血二次开胸止血、呼吸道感染和片周漏各l例,心动过速4例.术后随访24例(92.3%),随访时间1月~92月,晚期死亡l例,死因为片周漏并感染性心内膜炎.结论:成人室间隔缺损的临床表现虽较为复杂,手术效果令人满意.选择正确的手术方法及注意围术期处理是手术治疗成功的关键。  相似文献   
87.
自体骨膜游离移植修复关节软骨缺损进展   总被引:1,自引:0,他引:1  
探讨自体骨膜游离移植修复关节软骨缺损的研究进展。从骨膜的解剖生理功能和骨膜再生软骨能力两方面进行分析,并阐述了关节内营养环境、关节活动、骨膜生发层不同朝向、年龄及手术技巧等因素对移植修复的影响。同时总结了该方法的临床应用状况、效果及存在的问题。实验及临床的研究证明自体骨膜游离移植是修复关节软骨缺损的重要手段,局部环境因素影响骨膜成软骨。  相似文献   
88.
带血管蒂髌骨移位修复膝关节面缺损的应用解剖   总被引:1,自引:0,他引:1  
目的:研究用带血管蒂髌骨移位的方法修复股骨髁和胫髁关节面缺损。方法:用37例经动脉红色乳胶灌注的下肢标本,经解剖、厚切片和铸型研究髌骨的血供。观察30块髌骨和胫骨内外侧髁关节面的形态和面积。结果:供应髌骨的各支动脉在先在髌骨周围吻合成髌周动脉环,再由该环发支进入髌骨;参与形成髌周动脉环的主要动脉有膝上外动脉、膝下外动脉、膝降动上支,膝降动脉髌下支和膝下内动脉;髌骨关节面与股骨内外侧髁下关节面、胫骨内外侧形态大小相似。结论:带血管蒂骨可以移位至股骨内外侧髁、或胫骨内外侧髁,利用髌骨的关节面修复股骨髁或胫骨髁关节面缺损,以期最大限度地保留膝关节的功能。  相似文献   
89.
倍骼生在颌骨小范围缺损修复中的应用   总被引:1,自引:0,他引:1  
目的:观察倍骼生(Perioglas)在颌骨小范围缺损修复治疗中的应用效果。方法:对34例牙源性颌骨囊肿手术后缺损(直径≤30mm)和40例因 牙槽骨高度或厚度不足需行种植修复的病例应用倍骼生植入修复缺损,术后拍片检查并测量植入物高度的变化,观察其密度的变化。结果:倍骼生植入初期高度逐渐变低,密度逐渐降低,但4周以后高度不再减低,密度开始回升。8周以后渐趋近正常骨组织密度。 结论:倍骼生在骨缺损区植入时有骨引导和骨诱导的作用,对缺损区早期形成有功能性的、成熟的骨组织有促进作用。  相似文献   
90.
There is a deficit of literature regarding the association between nickel allergy–induced symptoms and implanted devices. This report describes a case of nickel allergy causing debilitating migraine-like symptoms, failing to resolve with medical therapy, requiring surgical removal of the device and repair of the defect.  相似文献   
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