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991.
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.  相似文献   
992.
老年人生活质量构成与保健模式探讨   总被引:5,自引:0,他引:5  
老年人随着年龄增长,健康状况下降,生活质量受到严重影响。如何认识和构建新型的多层次保健模式,以提高老年人的生活质量,使他们健康长寿,将成为社会关注的热点问题。  相似文献   
993.
A new impact response method using a fracture of a pencil-lead to produce an excitation pulse is proposed. Impact excitations (rectangular pulse, triangular pulse and half-sine pulse) are strictly given in physical and mathematical definitions and complete solutions to the impact excitations are provided for Noyes' model of the human tooth. When a relatively long triangular pulse is applied to Noyes' model, which can express the physical characteristic of periodontal tissues, a sinusoidal damped vibration of a single degree-of-freedom model is approximately obtained. The acceleration response is characterised by the physical parameters (T, δ and Ao) and mechanical elements (m1, c1 and k) of which a single degree-of-freedom model is composed. By means of this method, the values of the parameters and elements in the cases of healthy maxillary, healthy mandibular and pathological mandibular incisors are obtained. The single degree-of-freedom model can express the high-frequency spectra of Noyes' model. The pathological tooth is characterised by a longer damped time constant and a larger acceleration maximum. This impact response method can effectively be applied to clinical diagnosis in view of the physical parameters and mechanical elements which have been derived.  相似文献   
994.
This study was undertaken into rats to investigate changes in the hepatic lymph vessels and the space of Disse in endotoxaemia and to examine their relationship with the development of endotoxin-induced hepatic injury. Lymph stasis, namely dilatation of the lymph vessels and oedema, developed rapidly in the medium-sized portal canals, the large portal canals, and the liver hilum after endotoxin injection, but not in the small portal canals. Such changes reached their maximum 4-8 h after endotoxin injection and had recovered markedly by 16 h after the injection. The space of Disse remained within normal limits during this period. These findings suggest that the intrahepatic lymph stasis in endotoxaemia may be caused by a reduction in the pumping activity of the extrahepatic and the intrahepatic large lymph vessels rather than by an increase of lymph formation in the liver lobules. There was no evidence suggesting a direct relationship between the disturbance of hepatic lymph flow and the development of hepatic injury in endotoxaemia.  相似文献   
995.
Brachypodium distachyon is a ubiquitous, temperate grass species which is being developed and exploited as an alternative model to rice, in order to gain access to important syntenic regions of the genomes of less tractable relatives such as wheat. As part of this initiative, this paper describes for the first time the cytotaxonomy of members of the polyploid series of this species, and challenges the assumption that the series evolved simply by chromosome doubling. In situ hybridization using genomic DNA probes and rDNA markers uncovers a hybrid origin of several of the polyploid ecotypes, and sheds light upon the complex evolution of this species and its close relatives.  相似文献   
996.
伤肢小隐静脉修复腘动脉损伤解剖基础与临床应用   总被引:1,自引:0,他引:1  
目的:为利用伤肢小隐静脉修复腘动脉损伤提供解剖学依据。方法:对25具标本50侧肢体的腘动脉和小隐静脉进行解剖研究并分别测量其管径。结果:腘动脉与小隐静脉解剖关系恒定,腘动脉管径起始段为(6.6±0.9)mm,中段为(5.9±1.0)mm,分叉前为(4.9±0.9)mm,小隐静脉管径汇入处为(3.1±0.1)mm,外踝平面和中段管径均为(2.9±0.1)mm,在小腿的上段小隐静脉与大隐静脉和深静脉间交通支出现率低。结论:腘动脉与小隐静脉解剖关系恒定,管径较相近,在伤肢小腿的上段切取一段小隐静脉对静脉回流无明显影响,临床应用21例22侧肢体,效果可靠满意。  相似文献   
997.
目的观察灯盏花素(BRE)对大鼠心肌缺血再灌注(I/R)诱导细胞凋亡及凋亡相关基因Bcl-2、Bax表达的影响,并对其作用机制进行初步探讨。方法30只SD大鼠随机分为3组(n=10):①假手术(Sham)组:前降支穿线不结扎,观察1.5 h;②缺血再灌注(I/R)组:结扎前降支30 m in,再灌注前5 m in生理盐水(4 mg/kg)iv,再灌注1h;③BRE组:再灌注前5 m in应用BRE(4 mg/kg)iv,余同I/R组。常规方法检测丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性,免疫组化法测定Bc l-2、Bax蛋白的表达,通过细胞图像分析系统测量细胞阳性染色面积百分率,应用透射电镜观察心肌超微结构的变化。结果同I/R组相比,BRE组心肌组织MDA含量显著降低[(7.56±1.67)μmol/gvs(16.58±2.59)μmol/g,P<0.05],SOD活性显著升高[(2.37±0.22)mkat/gvs1.38±0.14 mkat/g,P<0.05],Bax蛋白表达显著降低(5.02±1.01vs18.59±5.68,P<0.01),而Bc l-2蛋白表达显著增高(17.48±4.72vs7.32±2.05,P<0.01),Bax/Bc l-2显著降低(0.29±0.57vs3.32±0.10,P<0.01),细胞阳性染色面积百分率显著减少(0.42±0.06vs13.84±1.97,P<0.01),细胞超微结构损伤明显减轻。结论BRE通过调控Bax/Bc l-2表达抑制心肌I/R诱导的细胞凋亡,对缺血再灌注心肌具有保护作用。  相似文献   
998.
目的探讨和评价闭合型双循环生物人工肝支持系统(CBC-BALSS)在治疗犬急性肝功能衰竭模型过程中的稳定性、安全性和有效性。方法建立犬急性肝功能衰竭模型(门腔分流联合胆总管离断),采用CBC-BALSS进行支持治疗。20只模型犬分为两组CBC-BALSS治疗组(n=11);无肝细胞CBC-BALSS对照组(n=9)。治疗时限6h。检测实验犬血氨、生化全套、凝血因子(FactorⅦ)、支/芳氨基酸(BCAA/AAA)、单乙基甘氨酸二甲苯胺(monoethylglycinexylidide,MEGX)和细胞循环路生化全套、肝细胞密度和数量。结果CBC-BALSS细胞回路细胞悬液总体积200ml,肝细胞的总数1×1010个、密度5×107/ml、活率98%左右。治疗中16只犬的生命体征平稳,在治疗30min内均出现一过性低血压;2只转流开始15min出现过敏反应;1只转流中因上消化道出血死亡;1只因穿刺部位出血死亡。模型治疗前血氨、ALT、TBil/DBil、白蛋白、FactorⅦ和BCAA/AAA分别达150mmol/L、400U/L、80/55mmol/L、35g/L、20%和1.6;CBC-BALSS治疗6h后,血氨、TBil/DBil下降均显著低于对照组;ALT存在下降趋势且在第6小时差异有统计学意义;白蛋白、FactorⅦ和BCAA/AAA在所有时段、组间差异均无统计学意义。在治疗1h和2h,MEGX差异有统计学意义,治疗组MEGX比对照组提前2h达最高点。治疗15~30min后,双循环路压力至115mmHg趋于平稳,且在±5mmHg波动。在治疗过程中,治疗组细胞循环路ALT显著性升高;组间细胞循环路TBil/DBil变化差异无统计学意义,而两组在各时间点均显著性升高;白蛋白变化无统计学意义。结论CBC-BALSS治疗犬急性肝功能衰竭过程中,安全、有效、稳定且代谢支持作用明显。  相似文献   
999.
目的探讨利多卡因预处理对肝细胞缺氧/复氧后Bcl-2、Caspase-3蛋白表达及细胞凋亡的影响。方法将体外培养的肝细胞分为三组:缺氧/复氧组(Ⅰ组)、利多卡因预处理组(Ⅱ组)和正常对照组(Ⅲ组),每组10份。检测肝细胞缺氧/复氧培养后细胞培养液中谷丙转氨酶(ALT)、谷草转氨酶(AST)浓度,肝细胞Bcl-2、Caspase-3蛋白表达、肝细胞凋亡率及超微结构变化。结果Ⅰ、Ⅱ组细胞培养液中ALT、AST浓度、肝细胞Caspase-3蛋白表达和肝细胞凋亡率较Ⅲ组均升高(P<0.05),透射电镜示肝细胞损伤,可见凋亡细胞;Ⅱ组细胞复氧后培养液中ALT、AST浓度、肝细胞Caspase-3蛋白表达和细胞凋亡率均低于Ⅰ组(P<0.05),而肝细胞Bcl-2蛋白表达较Ⅰ组升高(P<0.05),透射电镜观察也显示Ⅱ组肝细胞比Ⅰ组损伤轻微。结论利多卡因预处理可以在一定程度上减轻缺氧/复氧后肝细胞损伤,降低细胞凋亡率,保护机制可能与Bcl-2、Caspase-3蛋白表达有关。  相似文献   
1000.
The chemical warfare agent, sulphur mustard (SM), is a potent blistering agent in man. Skin exposure can produce partial-thickness burns which take up to three months to heal. The aim of this study was to investigate the use of early laser ablation as a means of accelerating this exceptionally slow rate of healing. Four circular partial-thickness SM burns were induced on the dorsum of nine large white pigs (under general anaesthesia). At 72 h post-exposure, three burns per animal were ablated with a single pass of an UltraPulse 5000C CO(2) laser, at a fluence of 5-6 J cm(-2). All the burns were dressed with silver sulphadiazine and a semi-occlusive dressing. At one, two and three weeks post-surgery three animals were culled and all lesions excised for histological analysis. Burn depth was confirmed and measurements of the radii of regenerative epithelium were performed allowing the area of the zone of re-epithelialisation in each lesion to be calculated. Laser-treated lesions showed a significant increase (350%) in healing rates compared to controls (p<0.005). At two weeks, the laser-treated sites were 95% healed in comparison with control sites (28% healed). These data suggest that laser ablation may be effective in the treatment of partial-thickness SM-induced skin injury.  相似文献   
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