DNA damage by the glycation products of glyceraldehyde 3-phosphate and lysine

Summary In order to evaluate whether base modifications, apurinic/apyrimidinic site formation, strand breaks, or a combination of these lesions results from the interaction of glycation products with DNA, plasmid DNA was first reacted with these products, and then subjected to digestion with endonuclease III and endonuclease IV of Escherichia coli. Analysis of the differential effects of digestions with these enzymes by electrophoresis on agarose gels demonstrated that reactive glycation products produce both base modification and apurinic/apyrimidinic sites in DNA, in addition to the strand breaks observed after incubation with glycation products alone. These types of DNA damage may occur in specific diabetic cells where elevated levels of glycating sugars are associated with pathologic dysfunction. [Diabetologia (1994) 37: 145–149] Received: 28 May 1993 and in revised form: 30 August 1993     

玻璃纤维增强复合树脂在总义齿基托中的应用

目的：增强总义齿基托的机械性能，提高总义齿的基托抗折裂能力。方法：对E－玻璃纤维用KH－550处理剂进行表面处理后，加入总义齿基托中，制成玻璃纤维增强复合树脂。结果：经过1年的临床观察后复诊，没有发现裂纹。结论：玻璃纤维增强得合树脂可以有效地增强总义齿基托的机械性能。     

颅底胆脂瘤的MRI特征

目的探讨颅底胆脂瘤MRI分型的意义及其MRI诊断特征。方法观察15例颅底胆脂瘤的CT、MRI与病理学资料，根据肿瘤T1WI信号的不同，将颅底胆脂瘤分为Ⅰ型和Ⅱ型，分析两型胆脂瘤在CT、MRI征象和颅底骨质侵犯等方面的差异。结果15例颅底胆脂瘤T2WI显著高信号，肿瘤实质无强化。15例中，Ⅰ型，6例，肿瘤位于桥前池和桥小脑角区，CT均匀低密度，T1WI均匀低信号，包膜不强化，颅底骨质改变轻微，肿瘤实质为胆固醇结晶；Ⅱ型，9例，肿瘤位于一侧中、后颅窝底，CT呈混杂密度，T1WI呈混杂信号，其中4例为低信号中夹杂少量高信号，另5例以高信号为主，包膜强化，颅底骨质呈显著外压性改变，肿瘤实质为角化上皮和蛋白。结论颅底胆脂瘤分为Ⅰ型和Ⅱ型是合理的，体现了两型颅底胆脂瘤组织病理和生物学行为的差异，对指导MRI诊断有积极意义。T1WI信号多样性、T1WI显著高信号、肿瘤实质不强化以及与MRI分型相关的颅底骨质侵犯是颅底胆脂瘤的MRI诊断特征。     

A ring electrode to record extraocular muscle activities during skull base surgery

Summary A ring-shaped electrode was developed and used in 20 patients to record evoked electromyographic responses directly from the extraocular muscles during skull base surgery. Intra-operative monitoring with this electrode helps the surgeon to localize the nerves that innervate the extraocular muscles precisely and to refrain from disturbing important neural structures during operations. Such monitoring also provides some insight into the pathophysiology of the dysfunction of these nerves resulting from skull base lesions.     

神经内镜与显微手术切除前、中颅底肿瘤

目的探讨神经内镜与显微神经外科技术在切除前、中颅底肿瘤中的意义和手术方法。方法应用神经内镜辅助的显微神经外科技术切除前、中颅底肿瘤89例,其中包括颅眶沟通瘤9例、颅鼻沟通瘤7例、颅眶鼻沟通瘤6例。在显微镜下尽可能切除可见的肿瘤部分,再用神经内镜寻找残余的肿瘤并切除。结果在常规显微神经外科切除肿瘤后,仍有不同程度的残余肿瘤,在内镜下进一步切除,80例(89.9%)肿瘤达全切除,6例(6.7%)获次全切除,3例(3.4%)为部分切除,无手术死亡。结论神经内镜辅助与显微神经外科技术切除前、中颅底肿瘤有助于提高肿瘤全切率,减少手术创伤。     

颅底脊索瘤的显微外科治疗

目的 探讨脊索瘤的诊断及综合治疗。方法 对105例颅底脊索瘤作回顾性分析研究。结果手术108例次，有3例病人复发后再次行手术治疗。肿瘤全切除14例次，近全切除65例次，全切和次全切除率为73．2％，大部及部分切除29例次。手术死亡2例。108例次手术中有34例次术后出现并发症。结论 采用显微外科治疗方法，选择适当的手术入路，是提高肿瘤切除率，降低术后并发症是治疗的关键所在。     

Clinical Course and Autopsy Findings of a Patient with Clival Chordoma Who Underwent Multiple Surgeries and Radiation during a 10-Year Period.

The management of clival chordoma remains problematic. We present the case of a 48-year-old woman with clival chordoma who underwent multiple surgeries and radiation therapy, including gamma knife stereotactic radiosurgery (GK-SRS), during a 10-year clinical course. The tumor was initially removed by gross total resection via the trans-sphenoidal approach, followed by external linac radiation therapy. The tumor recurred at the clivus 5 years after the initial operation. After repeated trans-sphenoidal removal of recurrent tumors, she twice underwent GK-SRS for a tumor remnant adjacent to the brainstem. Although this part of the tumor was controlled by GK-SRS, there was further tumor extension toward the sphenoid and maxillary sinuses. Ultimately, lower cranial nerve dysfunction developed due to tumor extension into the lower part of the clivus and the patient died of respiratory failure. Autopsy revealed the tumor to extend from the lower clivus to the bilateral middle fossae. The lower part of the tumor extended to the nasal cavity and to the posterior wall of the pharynx, resulting in compression of the upper pharyngeal region. The tumor around the jugular foramen compressed the lower cranial nerves bilaterally. Tumor cells did not, however, invade the intradural space microscopically. Although chordoma is not biologically malignant, this tumor can show massive extension with destruction of bony structures and extracranial invasion of connective tissues. Therefore, the optimal treatment strategy is to remove the tumor mass as extensively as possible, including normal bony structures and connective tissues surrounding the tumor, using skull base surgical techniques.     

鼻内镜治疗颅底疾病112例报告

目的探讨鼻内镜径路治疗颅底疾病的价值。方法2002年5月~2006年12月,对112例颅底疾病行鼻内镜径路手术,其中脑脊液鼻漏39例,垂体瘤4例,脑膜膨出或脑膜脑膨出3例,蝶筛囊肿9例,蝶窦炎伴息肉2例,真菌性蝶窦炎12例,内翻性乳头状瘤11例,鼻咽纤维血管瘤6例,骨化纤维瘤2例,骨纤维异常增殖2例,脊索瘤7例,颅咽管瘤2例,鳞癌10例,未分化癌1例,乳头状瘤癌变2例。结果全组均在鼻内镜下处理,其中20例病变为次全切除,包括鳞癌8例、未分化癌1例、脊索瘤7例、颅咽管瘤2例、骨纤维异常增殖2例。脑脊液鼻漏1次手术成功31例(79.5%),2次成功4例,3次成功4例,最终成功率100%。1例脑膜脑膨出术后2个月复发并伴脑脊液漏,内镜下再次手术成功。1例内翻性乳头状瘤术后11个月复发,改行鼻侧切开术。1例真菌性蝶窦炎术后4个月复发行再次内镜手术。1例脑脊液鼻漏术后颅内感染。结论鼻内镜径路可以处理多种颅底疾病,是一种安全、有效、微创的手术方式,但仍需严格掌握手术适应证,特别是恶性肿瘤。     

成年男性舌下神经在舌根部的定位研究

目的:探讨成年男性舌根部舌下神经解剖走行特点,指导临床舌根部射频温控减容术治疗阻塞性睡眠呼吸暂停低通气综合征(OSAHS)时针形电极刺入舌根部的部位及深度,以避免损伤舌下神经。方法:选择10具成年男性的舌标本,定型后在冰冻状态下作冠状切面,通过计算机图像处理与测量系统行舌下神经定位测量,并进行相关的统计学分析。结果:(1)两侧舌下神经呈对称性分布。(2)成年男性舌下神经舌内部分的主干(本实验为舌盲孔前后15mm范围内)其垂直向解剖走行基本恒定,距舌表面(22.21±2.22)mm;水平向走行中,舌盲孔后一般位于舌中内(近中线侧)(28.61±2.66)％处,舌肓孔前为(21.89±1.93)％处。结论:本实验为舌根部射频温控减容术治疗OSAHS提供了一个相对安全的范围:在不超过(22.21±2.22)mm深度且舌盲孔后避开中内(近中线侧)(28.61±2.66)％区域、舌盲孔前避开中(内近中线侧)(21.89±1.93)％区域,基本不会损伤舌下神经。     

义齿用Ti-6Al-7Nb合金铸件挠度的研究

目的：通过对相同长度、宽度、不同厚度的Ti-6Al-7Nb合金铸件挠度的测量,观察铸件厚度与挠度的关系,为确定Ti-6Al-7Nb合金铸造义齿基托的适合厚度提供实验依据。方法：参照ISO关于义齿基托材料挠度的标准,测量不同厚度Ti-6Al-7Nb合金铸件的挠度,并与纯钛、Ti-6Al-4V合金及Co-Cr合金对比。结果：Ti-6Al-7Nb合金、纯钛及Ti-6Al-4V合金铸件的厚度在0.65mm时可以达到义齿基托挠度的标准;Co-Cr合金在0.57mm时可达到标准要求。结论：在临床制作Ti-6Al-7Nb合金义齿基托时,厚度应不低于0.65mm。