A comparative study of using comet assay and gammaH2AX foci formation in the detection of N-methyl-N'-nitro-N-nitrosoguanidine-induced DNA damage.

Comet assay is a useful technique in the detection of DNA damages, particularly DNA strand breaks; and it has been utilized to show that a potent carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), can induce such damages. Recently, gammaH2AX foci formation has been suggested as another sensitive way to detect DNA double strand breaks (DSBs). However, there is no systematic comparison being conducted to evaluate the consistency of these two methods. Using MNNG as a model chemical, the sensitivity of neutral comet assay and gammaH2AX foci formation in detecting MNNG-induced damage was studied. It was found that at concentrations of 0.1 and 1 microg/ml, both methods can detect MNNG-induced damage in human amnion FL cells. However, at 0.1 microg/ml, comet assay revealed more percentage of cells with DNA damage than gammaH2AX fluorescence revealed. On the other hand, while gammaH2AX foci were readily formed at very early times by 10 microg/ml MNNG treatment, neutral comet assay did not detect any significant DNA damage at the same time points. In addition, 10 microg/ml MNNG induced a distinct whole nuclei staining pattern of gammaH2AX, a type of DNA damage which was not detected by neutral comet assay but could be detected by alkaline comet assay. Therefore, gammaH2AX may be used as a sensitive indicator for DNA damage.     

血管内皮生长因子与妊娠高血压综合征发病的关系

目的　探讨血管内皮生长因子 (VEGF)在妊娠高血压综合征发病中的作用。方法　分别采用酶联免疫吸附试验检测 40例妊高征孕妇的血清VEGF水平 ,免疫组化检测胎盘及蜕膜组织VEGF及CD3 4表达情况 ,35例正常孕妇作对照。结果　①妊高征组孕妇的外周血VEGF水平及胎盘组织MVD明显低于正常妊娠组 (P <0 0 5 ) ;②两组胎盘绒毛滋养叶细胞和蜕膜组织中均有VEGF阳性表达 ,胎盘组织强阳性表达高于蜕膜。与对照组比较 ,其胎盘组织VEGF强阳性表达的轻度妊高征无显著性差异 ;而中度和重度妊高征与对照组相比 ,则明显降低 ,差异显著 (P <0 0 5 )。各组孕妇蜕膜组织中VEGF的表达强度和差异无显著性。③孕妇外周血VEGF水平与新生儿出生体重 (r =0 2 9,P <0 0 5 )和胎盘重量 (r =0 34,P <0 0 1)均存在直线正相关关系。结论　妊高征患者血清VEGF水平和胎盘组织MVD降低 ,胎盘组织VEGF表达明显下降 ,都可能在妊高征的发病中起一定的作用。     

微创经皮肾镜取石术治疗上尿路结石

目的 探讨微创经皮肾镜取石术治疗上尿路结石的有效性和安全性.方法上尿路结石患者368例,平均年龄57岁.其中输尿管上段结石116例,结石大小(2.1±0.8)cm;肾结石252例,结石大小(4.6±1.4)cm,其中非鹿角形结石190例,结石大小(3.2±1.1)cm,鹿角形结石62例,结石大小(7.6±1.6)cm.均采用微创经皮肾穿刺,输尿管镜下气压弹道或联合钬激光碎石治疗,对结石清除率和并发症等进行统计分析.结果 368例患者中单通道取石356例(96.7%),双通道12例(3.3%).一期取石344例(93.5%),二期取石24例(6.5%).总结石取净率为88.6%(326/368).平均手术时间73 min.一期取净结石者住院时间4～8 d,平均6 d.术后发热14例(3.8%);输血5例(1.4%);2例肾结石术后出血严重者经输血及超选择性肾动脉栓塞后治愈.结论 微创经皮肾镜取石术损伤小、住院时间短、术中出血及并发症少、结石清除率高、可重复取石,是治疗上尿路结石有效的微创手段.     

神经导航下经岩骨幕上下联合入路中面神经管的解剖研究

OBJECTIVE: To study the value of neuronavigation in the transpetroal approach, and to provide anatomic data for the protection of the nerves in the facial nerve canal (FNC) during surgeries. METHODS: Simulated surgery through the transpetroal approach was performed on 16 sides of 8 adult cadaver heads with the assistance by neuronavigation. The anatomy of the facial nerve and the relationship of related structures were observed and the distances from the utmost external edge of the mastoid to different segments of the FNC were measured. RESULTS: Neuronavigation was successful with all the FNC, with the mean error of less than 0.9 mm. The FNC could be divided into 3 segments, the labyrinthine, the tympanic and the mastoid segments, stretching 3.6+/-1.2 mm, 11.2+/-2.5 mm and 16.1+/-3.6 mm respectively and with diameters of 1.2+/-0.3 mm, 1.4+/-0.1 mm and 1.7+/-0.2 mm, respectively. CONCLUSION: Neuronavigation may help protect the FNC during surgical procedures, and a thorough knowledge of the anatomic features of the FNC can be significant for preservation of the facial nerves.     

质子磁共振波谱对创伤后应激障碍患者海马神经元异常的诊断价值

目的 探讨质子磁共振波谱（1HMRS）在诊断创伤后应激障碍（post traumatic stress disorder，PTSD）患者海马神经元异常中的价值。方法 对19例PTSD患者及19例健康对照组行常规MRI和1HMRS检查。结果 PTSD患者MRI检查未出现信号的异常。19例患者两侧海马均显示NAA／Cr明显减低，与健康对照组相比，差异有统计学意义（P〈0．01）；而患者两侧海马的Cho／Cr与健康对照组相比，差异无统计学意义（P〉0．05）。结论 1HMRS揭示了PTSD时海马存在着神经元的丢失或功能紊乱，而这些改变是构成PTSD的神经生物学基础之一。     

老年人与青年人皮肤血流量比较研究

目的 判定增龄对皮肤血流量的影响。方法 用PIM2-LDPI检测皮肤血流量。结果 老年组前额、左手指背、命门穴部位皮肤血流量分别为:(1.94±0.86)V,(1.92±0.52)V和(0.71±0.19)V,与青年组比较差异无显著性。但是,老年男性在命门穴的皮肤血流量明显高于青年男性(P<0.05),老年女性前额的皮肤血流量明显降低(P<0.01)。男性比女性的皮肤血流量高。结论 皮肤血流量的差异无年龄相关性,男性组的皮肤血流量比女性组高。     

影响肝外伤手术死亡的危险因素分析

目的分析影响肝外伤手术死亡的危险因素,探讨其临床意义。方法根据AAST和ISS标准,回顾性分析90例肝外伤手术病例,对影响手术死亡的危险因素进行单因素比较和Logistic回归分析。结果死亡15例,其中Ⅲ级2例、Ⅳ级4例、Ⅴ级9例,总体手术死亡率17%。Ⅳ~Ⅴ级肝外伤手术方式的单因素比较提示:清创性肝切除术的相对危险度是0.73;而规则性肝切除术、肝静脉或肝后下腔静脉修补术相对危险度分别是1.32、1.52。Logistic回归分析提示:ISS分会和术中失血量是影响手术死亡率的2个独立因素。结论ISS分值、术中失出血量和手术方式是影响肝外伤手术死亡的3个重要因素,娴熟的手术技能和合理的手术方式可以减少术中出血量和降低手术死亡率。     

处女膜修补手术及麻醉方法的改进

目的；增大处女膜粘膜瓣的接触面，减少因麻醉造成的处女膜粘膜水肿，提高修复手术的成功率。方法：手术全部采用1％的卡因行粘膜表面麻醉。53例采用瓦合粘膜瓣法，3例用瓦合粘膜瓣联合阴道粘膜瓣修复法。结果：56例术后一月随访，53例处女膜孔径为一指，成功率94．64％。结论：采用1％的卡因粘膜表面麻醉，瓦合粘膜瓣法及瓦合粘膜联合阴道粘膜瓣修复法对处女膜修复是行之有效的。     

产超广谱β-内酰胺酶菌的检测方法及耐药性的比较

【目的】比较3种方法检测产超广谱β-内酰胺酶(ESBLs)菌株的检出率，了解近期广东省人民医院大肠埃希菌和肺炎克雷伯菌产ESBLs菌株的感染率及其耐药情况。【方法】walkaway-40机鉴定菌种，MIC初筛，双纸片协同试验，确证试验、药敏纸片扩散法。【结果】大肠埃希菌72株和肺炎克雷伯菌78株，确证试验检出率分别为46％和33％。上述产ESBLs菌株对三代头孢菌素和氨曲南大多耐药，对氨苄西林，环丙沙星多呈耐药，亚胺培南100％敏感，对5种复方制剂耐药率为18．2％～100％。【结论】双纸片协同法和NCCLs确证试验均是检测ESBLs的好方法，各实验室应重视ESBLs菌株的检测和药敏试验。     

开（牙合）患者舌位置变化研究

目的：研究开He患者的舌位置有无特征性变异。方法：利用舌背碘油造影方法，增加头颅侧位定位X线片上舌背的显影效果，在头颅侧位定位X线片上以舌体在固有口腔内的相对位置确定舌体的位置，通过开He与正常He者知位置的团体t检验比较，找出开He患者的舌位置变异特性。结果：开He患者与正常He者比较，舌根部与悬雍垂之间的间隙增大，舌背部与腭表面之间的间隙减小，舌尖部更靠近牙齿，结论：开He个体相对于正常He个体舌位置有向前，向上的变化特点，这可能是开He的病因之一。