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BACKGROUND: An augmented reality tool for computer assisted surgery named X-Scope allows visual tracking of real anatomical structures in superposition with volume rendered CT or MRI scans and thus can be used for navigated translocation of bony segments. METHODS: In a feasibility study X-Scope was used in orthognathic surgery to control the translocation of the maxilla after Le Fort I osteotomy within a bimaxillary procedure. The situation achieved was compared with the pre-operative situation by means of cephalometric analysis on lateral and frontal cephalograms. RESULTS: The technique was successfully utilized in 5 patients. Maxillary positioning using X-Scope was accomplished accurately within a range of 1mm. The tool was used in all cases in addition to the usual intra-operative splints. A stand-alone application without conventional control does not yet seem reasonable. CONCLUSION: Augmented reality tools like X-Scope may be helpful for controlling maxillary translocation in orthognathic surgery. The application to other interventions in cranio-maxillofacial surgery such as Le Fort III osteotomy, fronto-orbital advancement, and cranial vault reshaping or repair may also be considered.  相似文献   
3.
OBJECTIVE: To investigate the characteristics of the early stage treponema pallidum infected tissue in ear, nose, oropharynx and larynx and to raise relevance ratio of syphilis in nose and oropharynx and enhance doctor's self-protection awareness. METHODS: The histopathologic characteristics were studied by using HE staining, Warthin-Starry (W-S) staining was adopted to examine the treponema pallidum(TP) in lesion issue and its exudates smear for 12 cases biopsy tissues of suspicious syphilis. The diagnosis was confirmed by venereal disease research laboratory (VDRL), rapid plasma reagin circle test(RPR), treponema pallidum hemagglutination test(TPHA) and fluorescent treponemal antibody-absorption test (FTA-ABS). Treat with curing syphilis methods which published by nation. RESULTS: In the 12 cases mucous membrane specimen, the squamous epithelium proliferated, neutrophilic granulocyte infiltrated, within inherent membrane generous plasmacyte and lymphocyte infiltrated. W-S staining: plenty of treponema pallidum were found inside mucous membrane epithelium and exudate smear. Serology examination: 11 cases VDRL(++++), 7 cases RPR (+), 11 cases TPHA(+), 1 case FTA-ABS(+). After systemic treatment, 11 cases are clinically recovered. All patients serology become negative. CONCLUSION: W-S staining method can directly demonstrate histopathologic characteristics in early syphilis, in intrinsic membrane numerous plasmacyte infiltration. Combining with specific syphilis serology examination could increase diagnosis rate of syphilis in nose and oropharynx.  相似文献   
4.
妇女围孕期增补叶酸能够有效预防神经管缺陷等疾病的发生。随着对叶酸研究的不断深入,叶酸补充中出现了诸多问题。本文简要综述了叶酸在服用方式以及基础和临床研究中出现的值得讨论、已经引起关注和需要进一步研究探讨的问题,并提出了深入研究叶酸可能的发展趋势。  相似文献   
5.
脊柱侧凸翻修手术   总被引:1,自引:1,他引:0       下载免费PDF全文
目的探讨脊柱侧凸手术失败原因及翻修手术的处理方法。方法回顾性分析我院自1997年以来收治的脊柱侧凸矫形术后需要进行翻修手术患者33例。男10例,女23例。翻修时距初次手术时间平均为13.4个月(0.5.66个月)。33例患者共行43次翻修手术,其中29例进行1次翻修手术,2例进行3次翻修手术,2例进行4次翻修手术。另有4例患者增加脊柱矫形和融合,同时行脊柱前路松解、支撑植骨手术。结果翻修手术时间平均3.9h(1.5—7.3h),手术中平均出血601ml(50—2000ml),平均输血量643.3mk(0-2000ml)。术后随访平均27个月(3—67个月),未出现畸形加重、内固定失败等并发症。结论脊柱侧凸翻修手术是脊柱畸形矫形术后的一种补救手术。术前完善的手术策略和良好的手术技术是翻修手术的关键。  相似文献   
6.
Rh血型不合新生儿溶血病检测方法及应用   总被引:3,自引:0,他引:3  
产前检测Rh,D因子及抗人球蛋白(coombs)试验是必要的。测定Rh,D因子及抗D滴度使用木瓜酶方法。通过对11261例孕妇常规检查Rh,D因子,发现D阴性74例。Rh,D阴性妇女占6.5‰。22例Rh,D阴性的孕妇所分娩的新生儿均为Rh,D阳性。其中2例孕妇血清抗D滴度为1∶32,病情严重,宫内输血无效,胎死宫内。初产妇13例,占59%。活产20例,存活率90%。Rh因子及抗人球蛋白试验方法简便、易行,一般医院均可进行。对有流产史、输血史的孕妇检查Rh因子是十分必要的。在有条件的医院,对Rh,D阴性的产妇分娩Rh,D阳性的新生儿之后,产妇应预防性注射抗D免疫球蛋白  相似文献   
7.
Objective:To study the protective effects of the heat shock protein 70 (HSP70)induced by zinc sulfate on reperfusion injury following pancreaticoduodenal transplantation in rats.Methods :The homologous male Wistar rat model of heterotopic total pancreaticoduodenal transplantation was used. The ZnSO4 treated rats received the intravenous injection of Zn2+5 mins before and after operation at a dose of 5 mg/kg (Zn 1 group),10 mg/kg(Zn 2 group) and 15 mg/kg(Zn 3 group), and the control group with the same volume of saline. The tissue concentration of HSP70 was determined using Western Blot. In addition,blood sugar (BG) and serum concentration of amylase and lipase were examined 24h after transplantation, and the activity of myeloperoxidase (MPO) in the pancrease graft was measured at the same time. Histological observation was performed.Results:Light microscopic studies showed that histomorphological changes of pancreas in Zn 2 group and Zn 1 group were much less than those in control group and Zn 3 group. The value of BG and serum lipase and MPO in Zn 2 group < Zn 1 group 相似文献   
8.
目的 探讨过氧化物酶体增殖物对小鼠原代肝细胞生长周期的影响和配体过氧化物酶体增殖物激活受体(proxisome proliferators—activated receptor,PPAR)alpha在肝癌形成过程中的变化。方法 在小鼠原代肝细胞中加入PPAR配体Wy-14,643,经不同培养时间后,应用流式细胞仪、逆转录-聚合酶链反应及Western blot等方法检测细胞增殖和凋亡,细胞周期蛋白p21WAFI、cyclinD1的mRNA及蛋白的变化情况。结果 在小鼠原代肝细胞中加入Wy-14,643培养2、4、6d,S+G2/M期细胞比例分别为(42.3±1.2)%,(50.3±2.1)%,(52.1±2.3)%,细胞凋亡率分别(9.0±0.2)%,(7.9±2.O)%,(7.4±1.3)%,与未加药组相比,细胞增殖明显增高(P〈0.05),凋亡明显减少(P〈0.05);各加药组cylinD1 mRNA和蛋白的表达也比对照组明显增高(P〈0.05);各加药组p21^WAF1 mRNA与对照组相比表达无显著变化(P〉0.05),第4天开始出现p21^WAF1。蛋白的表达显著增加(P〈0.05)。结论 过氧化物酶体增殖物通过其配体PPARα引起细胞周期蛋白的改变,导致正常细胞周期信号的传导紊乱,引起细胞异常的增殖和凋亡,从而有可能诱发肿瘤。  相似文献   
9.
目的探讨癫痫患者应用氟马西尼之后,用磁共振弥散成像(diffusion-weighted magnetic imaging,DWI)检测脑组织发生的改变,从而确定癫痫灶的位置。方法选择准备手术的癫痫患者20例,其中检查前2个月内服用过苯二氮卓类药物(benzodiazepine,BZD)有9人,另取17位未发做过癫痫的健康者作为对照。在患者清醒和完全的发作间期进行磁共振弥散成像基线扫描,然后静脉推注氟马西尼(flumazenil,FMZ),注射10min后,再次进行DWI检查。所有的病人测量下列双侧结构的表观弥散系数(apparent diffusion coefficient,ADC):海马、海马旁回、丘脑、中央白质、与癫痫灶相连的皮质。健康对照者进行了DWI检查,测量了上述结构。我们还对20位患者进行了注射FMZ前后的视频脑电图比较。结果与健康对照者对比,颞叶癫痫患者发病侧海马的发作间期ADC基线明显升高(P<0.05)。在注射氟马西尼后,不同感兴趣区的平均ADC变化如下:近期服用过BZD的患者癫痫发作侧的海马ADC下降(P<0.05);癫痫发作侧的海马旁回ADC下降(P<0.05),而近期没有服用过BZD的患者,未发现上述变化。在视频脑电监测中,服用BZD的患者也更易用FMZ诱发出癫痫波。在颞叶以外癫痫我们没有观察到统一的变化模式。结论近期服用过BZD药物的颞叶癫痫患者中,注射氟马西尼引起的ADC改变和癫痫灶的位置密切相关。核磁共振弥散成像清楚地表明了颢叶癫痫患者潜在癫痫灶的位置,是一个有效检测方法。  相似文献   
10.
Study of pathological morphology in chronic sinusitis]   总被引:1,自引:0,他引:1  
OBJECTIVE: To study the pathological characteristics and regularity of chronic sinusitis (CS) in different clinical types, tc estimate the reliability and feasibility of CS classification on the pathologic basis. METHODS: HE, Van Gieson's, alcian blue-periodic acid-schiff(AB-PAS) staining was used to observe the changes of epithelium, to measure the thickness of basement membrane and the area of mucous glands. The ultrastructural changes of pseudostratified ciliated columnar epithelium were observed under transmission electron microscope (TEM) and scanning electron microscope (SEM). RESULTS: The epithelial fiber tissue was increased, the basement membrane was thickened, and the mucous glands were obviously increased in CS under the light microscope. Subepithelial fibrosis and thickened basement membrane were most obviously seen in type III of CS and the hyperplasia of mucous glands was most distinct in type II. Under the TEM, abnormal structure of cilia, decrease of ciliated cells, increase of goblet cells were detected in all three CS types. Under the SEM, the cilia of every types showed the ingravescenced process of pathological changes from slight cilium disorder, disorientation, to desquamation of most cilia and replacement of microvilli. CONCLUSION: There is significant distinction of mucous membrane structure among three types. The Chinese classification of CS has pathological basis, it represents the occurrence, development and regularity of CS, and it can be used as basis in further study, communication and evaluation for surgical effect of CS.  相似文献   
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