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41.
目的:介绍同种异体半月板移植并总结4例关节镜辅助下的同种异体半月板移植的初步临床效果。材料和方法:2005年6月~7月,4例半月板切除术后的患者接受关节镜辅助的同种异体半月板移植手术,其中男性3例、女性1例,平均年龄30.78±7.71岁(21.5~38.5岁)。3例内侧半月板移植,1例外侧半月板移植。随访采用症状询问,体征检查,IKDC、Lysholm和Tegner评分及KT2000测量关节稳定性的方法。4例患者均每半年进行一次X线片及MRI检查,分别观察膝关节的关节间隙改变及移植半月板状态。对所得结果,因病例只有4例,故只进行数据描述,不进行统计学分析。结果:对4例患者均进行了平均21.80±0.81(20~22)个月的随访。所有患者随访时关节活动度均正常,均无明显的膝关节疼痛和肿胀,原来长时间活动后被切除半月板的间室不适完全消失。患者可以胜任日常活动和体育锻炼,无并发症出现。IKDC、Lysholm、Tegner评分均较术前明显提高。KT2000测量发现术后膝关节的稳定性有所改善。X线片检查提示术后患者关节间隙无明显变化。每半年一次的MRI检查提示移植半月板术后1年时替代存活已经很好。结论:关节镜辅助下的同种异体半月板移植安全可行,半月板移植可缓解半月板切除后出现的关节疼痛、肿胀等症状,促进关节功能恢复并使膝关节的稳定性有所改善。  相似文献   
42.
目的 研制新型胫骨串孔型髓内钉并对其进行生物力学研究。方法 用TAMZ合金制造远端锁孔由一个三个同样直径的串孔所替代的 9根新型胫骨髓内钉。将髓内钉安装在自行设计的夹具中 ,先将 3根新钉进行静态垂直压缩实验 ,根据静态实验结果 ,分别测试 6根新钉的动态疲劳强度。结果 新钉的静态压缩破坏载荷为 2 1 33N ,是人平均体重的 3倍多 ;通过 5 0万次压缩循环的条件疲劳强度为 1 2 0 0N ,约是人体重的 2倍。结论 新钉不仅能够方便临床使用 ,而且拥有较好的力学特性  相似文献   
43.
Pulmonary alveolar macrophages lavaged from tobacco smokers release increased levels of oxidants and have been implicated in the pathophysiology of emphysema. It is unknown whether lung macrophages recovered from marijuana smokers also liberate excessive levels of oxidants. To evaluate this possibility, pulmonary alveolar macrophages were obtained by bronchoalveolar lavage from nonsmokers, smokers of marijuana only, smokers of tobacco only, and smokers of tobacco plus marijuana. Spontaneous and stimulated superoxide anion release was measured by the superoxide dismutase-inhibitable reduction of ferricytochrome c. These findings were correlated with recent lung function tests. Superoxide anion production by macrophages, studies of small airway integrity (closing volume, closing capacity, and the slope of Phase III of the single-breath nitrogen washout curve), and evaluation of alveolar gas exchange (diffusing capacity of carbon monoxide) were similar in both nonsmokers and marijuana smokers. However, tobacco smoking was associated with both significantly higher levels of superoxide anion release by pulmonary alveolar macrophages and significant abnormalities of small airway function and alveolar diffusing capacity. Based on the results of this study, pulmonary alveolar macrophages of marijuana-only smokers do not produce increased amounts of oxidants when compared to macrophages of non-smoking subjects. This observation may account for the absence of abnormalities in small airway function and alveolar diffusing capacity in marijuana-only smokers, in contrast to the presence of such findings in smokers of tobacco, regardless of marijuana use.  相似文献   
44.
Extended healing time and lack of documented effective treatments of sacrococcygeal pilonidal disease create substantial problems. Locally applied zinc oxide has been reported to promote wound healing. We have compared topical zinc oxide (3%) with placebo meshes for pilonidal wounds healing by secondary intention in a randomized, double‐blind, placebo‐controlled multicenter trial. Sixty‐four consecutive patients, 53 males, aged between 18 and 60 years (median 26 years) with excised pilonidal wounds were centrally randomized to local zinc oxide (30 mg/g, n = 33) or to placebo (n = 31) mesh treatment. Patients were followed with strict recording of beneficial and harmful effects. The median healing times were 54 days (42–71 days, interquartile range, n = 33) for the zinc group and 62 days (55–82 days, n = 31) for the placebo group. This difference was not statistically different (p = 0.32). Based on Cox regression analysis initial wound volume influenced healing negatively (p = 0.016) while smoking (p = 0.011) was associated with faster wound healing. Significantly (p < 0.01) more placebo (n = 12) than zinc oxide‐treated patients (n = 3) needed antibiotics postoperatively. Although topical zinc oxide increased (p < 0.001) wound fluid zinc levels (1830 ± 405 μM, mean ± SEM) compared with placebo (3.1 ± 1.6 μM) serum‐zinc levels did not differ significantly between the zinc (13.5 ± 0.4 μM) and placebo (12.8 ± 0.4 μm) groups on postoperative day 7. No adverse events were recorded. Topical zinc oxide treatment did not accelerate time to closure of open pilonidal wounds but was associated with reduced antibiotic usage.  相似文献   
45.
目的探讨食管癌围手术期死亡原因及影响因素。方法总结1970年-2004年1858例食管癌手术患者临床资料,选择17个可能影响围手术期死亡的因素,应用Cox回归模型进行多因素分析。结果1858例食管癌手术患者围手术期死亡36例(1.94%)。呼吸系统并发症是引起围手术期死亡最常见的原因(41.7%)。Cox模型多因素分析显示严重吞咽困难、长期重度吸烟史、手术时间和手术年代是影响食管癌围手术期死亡的独立因素(P<0.05)。结论加强营养、改善肺功能、缩短手术时间是降低食管癌围手术期死亡率的重要方法。  相似文献   
46.
BACKGROUND: Cognitive impairment after stroke associates with various factors, such as age, educational years, etc. Besides concerning about the recovery of limb function after stroke, we should also focus on the rehabilitation of cognition. Moreover, we'd better pay attention to the control of all the risk factors of stroke, and improve the quality of life in stroke patients. OBJECTIVE: To analyze the factors that affect cognitive impairment after stroke. DESIGN: A related factors analysis. SETTINGS: Department of Neurology of Dalian Port Hospital and Dalian Second People's Hospital. PARTICIPANTS: Totally 148 stroke inpatients were selected from Department of Neurology, Dalian Port Hospital and Dalian Second People's Hospital from April 2004 to December 2005, including 100 males and 48 females, aging 45-75 years with an average age of (67±8) years; Their educational years ranged 2-10 years with an average of (6.1±3.7) years; The disease course ranged 15-30 days; All were right-handed. Inclusive criteria: All were accorded with the diagnostic standard set by the Fourth National Academic Meeting for Cerebrovascular Disease; Confirmed by CT or MRI; Informed consents were obtained from all the subjects. METHODS: After the disease conditions were stable, the patients were assessed with Wechsler memory scale (WMS) and Wisconsin card sorting test (WCST). WMS included forward and backward recitation of numbers and short-term memory (verbal memory, visual recognition). The number of times for correct and wrong classifications in WCST and the time to complete the trail making tests A and B were recorded. The focal volume, area and layer were recorded at 24 hours after admission. The general data of the patients were recorded, including name, sex, age, educational years, history of hypertension, history of diabetes mellitus. Electroencepalograph (EEG) was examined to record the wave shape, blood lipids were detected, and the cognition related indexes were analyzed with the Pearson correlation analysis. The correlation between cognitive indexes after stroke and the influencing factors were analyzed with multiple linear regression analysis. MAIN OUTCOME MEASURES: ① Correlation between cognitive indexes and imaging indexes; ② Influencing factors for cognitive indexes after stroke. RESULTS: All the 148 stroke patients were involved in the analysis of results. ① Correlation between cognitive indexes and CT indexes: There were obvious negative correlations between numerical symbol and focal layer (r =-0.234, P < 0.05), as well as between verbal memory and the focal area and volume (r =-0.363, -0.279, P < 0.05); Trail making test A had obvious positive correlation with focal area and volume (r =0.256, 0.256, P < 0.05). Results of multiple linear regression analysis: Correct classification was correlated with triglyceride (partial wave and θ wave (partial regression coefficient=0.231-0.908, P < 0.05); Verbal memory was correlated with EEG α wave, focal volume, sex, educational years and diabetes mellitus (partial regression coefficient=0.219-1.017, P < 0.05-0.01). Visual recognition had correlation with educational years and hypertension (partial regression coefficient=0.326, -1.163, P < 0.01). Trail making tests A and B were correlated with focal volume (partial regression coefficient=4.680, -18.561, P < 0.05). CONCLUSION: The factors that affect the cognitive function after stroke include sex, age, educational years, hypertension, diabetes mellitus, triglyceride, EEG wave shape, and the focal area, volume and layer  相似文献   
47.
48.
目的应用电子计算机体层摄影(CT)观察全身麻醉诱导前后肺不张的变化。方法8例择期行神经外科手术的患者,于麻醉前、麻醉诱导插管后行全肺CT扫描,选择肺尖、肺门、右膈顶上1cm三个层面的CT图像分析观察肺不张的变化。结果三个层面中,右膈顶上1cm层面的图像麻醉前后变化最明显,麻醉诱导插管后监测到明显的肺不张。结论全麻导致患者肺不张的面积和百分比增加,围术期肺部CT扫描能有效地监测到肺不张的发生,有助于优化术中机械通气,减少肺损伤。  相似文献   
49.
目的探讨肾上腺肿瘤MR扩散加权成像(DWI)表现,分析良、恶性肿瘤表观扩散系数(ADC)值之间的差异及ADC值与肿瘤细胞密度的相关性。资料与方法采用屏气单次激发自旋回波-回波平面成像.扩散加权成像(SE-EPI-DWI)技术,分别选取3个不同b值检查4|D例47个肾上腺肿瘤,其中恶性肿瘤18个,良性肿瘤29个;观察DWI表现,比较ADC值差异,并进行受试者工作特征曲线(ROC)分析,以选取肾上腺肿瘤DWI最佳成像b值和ADC值诊断阈值;对其中27个手术切除的肿瘤,在光镜下计数肿瘤细胞密度,并分析其与ADC值相关性。结果b值的大小影响DWI上肿瘤显示及其信号强度;肾上腺良、恶性肿瘤均可表现为均匀的高信号或不均匀高信号,并与肿瘤的类型及囊变、坏死程度有关,其间ADC值差异有统计学意义。经ROC曲线分析,肾上腺肿瘤DWI最佳成像b值为800s/mm^2,以ADC≥1.21×10^-3mm^2/s为阚值,诊断肾上腺良性肿瘤的敏感性为79%、特异性为72%。肾上腺肿瘤ADC值与其细胞密度负相关,以b值取800s/mm^2时相关性最强(r=-0.723,P〈0.01)。结论DWI对肾上腺肿瘤性质鉴别具有价值,是对常规MR检查的有益补充;测量肿瘤ADC值有可能为在体鉴别肾上腺肿瘤性质和病理分级提供新方法。  相似文献   
50.
目的: 观察细胞内游离Ca2+([Ca2+]i)在培养的不同发育阶段皮层神经元无镁诱导惊厥性损伤中的作用,探讨惊厥性脑损伤年龄依赖性的可能机制.方法:体外培养6 d、17 d的胚胎大鼠皮层神经元用无镁细胞外液处理3 h,或于无镁处理前用NMDA(N-甲基-D-门冬氨酸)受体拮抗剂或Ca2+通道阻滞剂预处理,用MTT代谢率测定的方法检测神经元损伤,以Fluo-3作标记用激光共聚焦显微镜扫描的方法检测[Ca2+]i.结果:体外培养6 d、17 d的神经元单纯无镁组MTT代谢率较同期对照组降低.应用MK-801 10 μmol*L-1、AP-5 50 μmol*L-1、尼莫地平10 μmol*L-1预处理后再给无镁处理,培养6 d、17 d的神经元MTT代谢率均不同程度高于同期单纯无镁组.培养6 d、17 d的神经元相对荧光强度之间差异有显著性,两者与基线荧光强度比较差异亦有显著性.应用上述各种拮抗剂后,[Ca2+]i改变的峰值均明显低于同期单纯无镁组.结论: 在体外不同发育阶段的神经元,短暂无镁处理诱导惊厥样放电所引起的神经元线粒体功能损伤以及[Ca2+]i改变程度不同.这种[Ca2+]i改变的年龄依赖性可能是惊厥导致神经元损伤的年龄依赖性的机制之一.NMDA受体-Ca2+通道激活是导致这种[Ca2+]i改变及神经元损伤的关键环节.  相似文献   
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