197例儿童意外伤害原因分析

目的 探讨儿童意外伤害的原因。方法 回顾性分析我院1998年3月至2000年10月急诊室就诊的197例儿童意外伤害病例。结果 儿童意外伤害有其身的特殊性，人为因素占有重要地位。结论 儿童意外伤害应以预防为主，采取家庭、学校、社会相结合的预防方法。     

Microbial differences in 2 clinically distinct types of failures of osseointegrated implants

This investigation is the result of a multicenter research project between the Catholic University of Leuven and the University of Madrid with the purpose of studying histometrically and ultrastructurally periimplant marginal tissue reactions in medium-term Brånemark implants. 12 patients were selected and distributed according to predefined clinical and radiological parameters into a periimplant infection group (A) and a non-periimplant infection group (B). Biopsies were taken from these patients and analyzed by means of microscopy (LM), histometry (HM) and transmision electron microscopy (TEM). With LM group A showed pathological features consistent with an advanced gingivitis lesion, while group B showed signs of healthy gingiva in the connective tissue and vauolae formation in the epithelium. With HM, group A showed significantly higher transmigration of inflammatory cells in the epithelium than group B. In the connective tissue, group A showed a higher % of inflammatory infiltrate with significantly higher numbers of plasma cells and mononuclear cells than group B. With TEM, group A showed an ultrastructural picture consistent with plaque-induced periodontitis, while group B showed a rather healthy connective tissue and vacuolae formation in the epithelium. These results suggest that supra-crestal marginal tissues around osseointegrated implants react to plaque bacteria similarly to periodontal tissues around teeth by chronic inflammation.     

人工破膜对缩短产程的作用的临床研究

人工破膜是一简便易行的产科干预方式。它对产科所起的促进作用已越来越被人们所认可。在产程初期.可诱发富缩、引产.在中晚期又可以加强宫缩、缩短产程。本文分析人工破膜112例产程发现:平均初产妇缩短产程7.59小时,经产妇6.05小时。活跃期前(宫口<4cm)平均每10分钟增加宫缩0.6次,活跃期后(宫口≥4cm)每10分钟增加宫缩13次。由此可见,人工破膜可明显加速产程.破膜后胎头代替前羊水囊的作用,使增大的半径对宫颈的压迫扩张作用增强.羊水流出后,宫内容积减小,压力下降,子宫肌纤维变短。使宫缩强度增加.近来研究表明,前列环素及血栓素对软化宫颈,促宫颈成熟有重要作用,而破膜可使上述物质增加.破膜还可产生催产素作用较理想的内环境,使子宫对催产素的刺激更敏感、自发宫缩加强、催产素有效量降低。同时并未见并发症增加。因此,人工破膜对计划分娩不失为一可行之良策。     

人工肝支持治疗时中心静脉置管的护理

目的探讨中心静脉置管在人工肝治疗中出现的护理问题及处置措施。方法对830例中心静脉置管的患者进行回顾性分析。结果中心静脉置管常见的护理问题是：导管相关性感染（3．5％）、局部渗血和皮下血肿（2．5％）及导管内血栓的形成（2．0％）。结论通过加强人工肝支持治疗中中心静脉导管的护理，能够显著降低并发症的发生率。     

Design and biomechanical properties of dental implant pore structure based on three-dimensional finite element analysis北大核心

BACKGROUND: Studies have shown that the elastic modulus can be changed by changing the pore internal unit structure when designing porous implants, providing a new way to better balance implant strength and elastic modulus. OBJECTIVE: To analyze dental implant biomechanical properties with different micro pore structures by finite element analysis so as to elucidate the effects of different micro pore structures on the surrounding bone stress and implant physical properties. METHODS: A mandibular model and three finite element models of dental implants with different pore structures (conventional structural pores, composite structural pores, and G7 structural pores) were built by CT scanning with porosity of 40%, the thickness of the porous layer of 1.2 mm, and the pore size of 0.45 mm. The ultimate force state was simulated to apply load to each model, which was operated by ANSYS finite element software and analyzed by surrounding bone stress and strain of the implants. RESULTS AND CONCLUSION: (1) When implants were subjected to the ultimate force, the maximum values of effector forces such as 38.324, 56.574, 64.694 MPa for conventional structure, composite structure and G7 structure dental implants on the surrounding cortical bone were respectively 1.836, 10.221, 9.439 MPa, and the maximum values of effector forces such as implants were 156.38, 476.23, 457.76 MPa. The maximum surrounding bone stress of the composite structure implant was within the range of promoting osseointegration. (2) When only lateral forces were applied to the implants, the maximum strain values of dental implants placed in the conventional structure, composite structure and G7 structure were 2.222 9×10-2, 1.661 9×10-2, 3.210 9×10-2 mm/mm. When only axial forces were applied to the implants, the maximum strain values of dental implants placed in the conventional structure, composite structure and G7 structure were 2.266 2×10-3, 1.844 6×10-3, 2.971 5×10-3 mm/mm, indicating that when subjected to lateral static load and axial load, the strain of the composite structure implant was smallest and the micro-movement was small, which helped to improve the osseointegration effect. (3) The results showed that the surrounding bone stress changed significantly with the change of pore unit cell structure inside the porous implant, and the mechanical properties of the implant also changed, and the change of unit cell structure shape of the porous structure on the implant surface significantly affected the elastic modulus and the mechanical properties of the implant. Dental implants with a composite pore structure had better biomechanical properties compared with conventional constructs and G7 constructs. © 2022, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved.     

前置胎盘、胎盘粘连、胎盘植入与人工流产的关系

目的探讨前置胎盘、胎盘粘连、胎盘植入与人工流产的关系。方法采用回顾性自然研究方法,收集我院1999年1月-2006年12月的产科分娩病例共4628例,按人工流产次数(0、1、2、≥3次)分为A、B、C、D四组,统计每组前置胎盘、胎盘粘连、胎盘植入的发生率,并进行统计学分析。结果A、B、C、D四组的发病率分别为2.9%、7.4%、10.8%、32.0%,经统计学处理,差异有高度显著性(χ2=448.57,P<0.01),且以胎盘粘连的发生率较高(χ2=15.78,P<0.05)。结论无人工流产者前置胎盘、胎盘粘连的发生率最低,且无胎盘植入发生,随着人工流产次数的增加,前置胎盘、胎盘粘连的发生呈明显上升趋势,多次人工流产可发生胎盘植入。     

Use of an Ellipsoid Artificial Heart

Experiments with the Poisk model of an ellipsoid artificial heart are reported. With a modified model of the diaphragm type made from polyurethane, calves survived for a mean of 55 days, with a maximum survival of 3 months. With adequate anticoagulation therapy, no thrombogenesis was observed in the blood chamber (except for the inlet valves); a low level of plasma hemolysis was observed postoperatively. Good correlation was demonstrated between the stroke volume and left and right atrial pressures. Changes in the blood coagulation indices are reported. Implantation of a clinical variant of this prosthesis into human cadavers demonstrated no difficulties in placing the heart in the pericardial cavity. Developmental efforts are continuing.     

Immune responses to implanted human collagen graft in rats

Immunity to collagen implants may be mediated by cellular and humoral immune responses. To examine the possibility of such immunological reactivity and crossreactivity to collagen, 39 Sprague-Dawley rats (female, 10 weeks old, approximately 250 g wt) were implanted subcutaneously at thigh sites with crosslinked, freeze-dried human placental type I collagen grafts (4 x 4 x 2 mm) which had been irradiated (520 Gray) or left untreated. Blood was obtained by intracardiac sampling prior to implantation or from normal rats, and at various times afterwards when the animals were sacrificed. The sera from these animals were examined for circulating antibodies to human, bovine and rat tail (type I) collagens by enzyme-linked immunosorbent assay (ELISA). Also, the lymphoblastogenic responses of spleen lymphocytes from the irradiated collagen-implanted animals were assessed in culture by measuring thymidine uptake with autologous and normal rat sera in the presence of human and bovine type I collagens. Implantation of the irradiated and non-irradiated collagen grafts in rats led to a significant increase in the level of circulating antibodies to human collagen. Also antibody to bovine and rat tail collagens was detectable in the animals implanted with irradiated collagen grafts but at a lower level than the human collagen. There was a raised lymphoblastogenic response to both human and bovine collagens. The antibody level and lymphoblastogenesis to the tested collagens gradually decreased towards the end of the post-implantation period.     

应用新型合成韧带施行颈椎前路椎间融合术的实验研究

目的：通过动物对照实验的方法，确定一种新型合成韧带在颈椎间隔合术的应用价值。方法：12只成年羊随机分为2组各接受单纯间盘摘除椎间植骨融保术或加合成韧带固定术，术后拍片了解植骨融合情况，术后12周时杀死动物，取颈椎标本分别行组织学和生物力学比较并进行统计学分析。结果：韧带组融合率为83％，对照组为67％，生物力学测试表有韧带组在伸展运动上有明显高的稳定性，屈曲运动的稳定性无差异。组织学分析表明2组动物的融合部位均为纤维组织、软骨及少量的骨组织、且之间无差异。结论：颈椎前路有融合应用新型合成韧带可以提高融合率和颈椎伸方向的生物力学稳定性，可作为颈椎前路固定的一种方法。     

Current status of 3D printing in spine surgery

Three-dimensional printing (3DP) is one of the latest tools in the armamentarium of the modern spine surgeon. The yearning to be more precise and reliable whilst operating on the spine has led to an interest in this technology which has claimed to achieve these goals. 3D printing has been used pre-operatively for surgical planning and for resident or patient education. It has also found its way to the operation theatre where it is used to fabricate customized surgical tools or patient-specific implants. Several authors have highlighted significant benefits when 3D printing is used for specific indications in spine surgery. Novel applications of this technology in spine surgery have also been described and though still in a nascent stage, these are important for this technology to sustain itself in the future. However, major limitations have also come to light with this technology in use. This article seeks to review the current status and applications of 3D printing in spinal surgery and its major drawbacks while briefly describing the essentials of the technology. It is imperative that the modern spine surgeon knows about this important innovation and when and how it can be applied to improve surgical outcomes.