机械应力对幼鼠髋臼发育影响的实验研究

目的阐明异常机械应力对髋臼发育和髋臼软骨生长板内软骨细胞增殖的影响,探讨髋臼发育不良的修复方法。方法将60只3周龄的雌性Wistar大鼠分成3组,每组20只,左侧髋关节为实验侧,右侧为对照侧。A组:在2周内反复将髋关节手法脱位后再复位;B组:膝关节伸直位钢针固定,制作髋臼发育不良的动物模型,2周后拔出钢针;C组:持续伸直位固定膝关节。三组动物分别于第5、7、9、12周时进行钼靶软X线、组织形态学及透射电镜观察。结果A组第5周时唇缘变钝,髋臼角比对侧增大约5°,软骨生长板内增殖层软骨细胞极向紊乱,SO染色无差异,圆韧带有淋巴细胞浸润,第7、9、12周时变化小,两侧无差异;B组第5周时髋臼角比对侧明显增大,第7周时唇缘变钝、内翻,纤维增生,柱状细胞极性紊乱,肥大细胞层增多,第9、12周时接近正常,12周时髋臼角为23.4°,髋臼入口最短径为5.0mm;C组髋臼角比对侧持续增大,没有任何改善倾向,第12周时唇缘内翻、扁平,无明显柱状细胞排列,细胞核变小,细胞器减少,空泡形成,髋臼角为71.3°,髋臼入口最短径为2.9mm。结论在髋臼发育旺盛期解除异常机械应力、恢复头臼同心,髋臼发育不良有治愈倾向。造成髋臼发育不良的直接原因是软骨生长板内增殖层软骨细胞代谢功能发生改变,骨化延迟。     

Mechanobiology and force transduction in scars developed in darker skin types

BACKGROUND: Scarring is a complex process involving many cell types, cytokines and biological pathways including mechanobiology. Some subtle mechanical properties of skin can be assessed by measuring the speed of ultrasound shear wave propagation. The orientation of abnormal skin tension forces can be visualized, particularly in darker skin types, using dermoscopy showing distinct patterns of rete ridges' conformation. AIM: To assess some mechanobiological features of scars in darker skin types. PATIENTS AND METHODS: Large atrophic and hypertrophic surgical scars were examined on the trunk of 35 darker skin subjects. The surrounding skin was used as a comparator. Dermoscopic aspects were recorded. Resonance running time measurements (RRTM) were performed using a shear wave propagation device (Reviscometer). They were performed in four specific directions at given angles with regard to the long axis of the scar. The minimum, maximum and mean RRTM values were recorded at each site. RESULTS: Dermoscopy revealed patterns of melanin deposits in scars distinct from the normal honeycomb network seen in the surrounding skin. Hypertrophic scars showed a patchy pattern of large macular melanoderma dispersed in a lighter background. In these cases, low RRTM values were obtained with little variations according to the orientation of the measurements. By contrast, atrophic scars showed a streaky laddering melanotic pattern under dermoscopy. Higher RRTM values were often obtained, particularly in the transversal direction of the scars. Mechanical anisotropy was greater in the atrophic scars compared with the normal skin. DISCUSSION: Darker skin types represent a model for visualizing the main orientation of the epidermal rete ridges. A correlation was found between the pattern of melanized rete ridges of scars and the main orientation of the intrinsic forces in the skin.     

Symptoms, diagnosis and endoscopic management of common bile duct stones

Symptomatic BDS commonly cause significant morbidity and attempt at stone removal should be attempted if possible. Complications of CBDS include biliary colic, jaundice, cholangitis and pancreatitis. Investigations aimed to predict the presence of stones within the bile duct include serum bilirubin, AST, ALP, common bile duct diameter and age as independent predictors of choledocholithiasis. TUS is a sensitive test in detecting bile duct dilatation but the sensitivity is reduced in its ability to detect choledocholithiasis. A NIH consensus statement found that ERC, MRC and EUS were comparable in their sensitivities, specificities and accuracy rates for detection of choledocholithiasis. ERC and stone removal using a balloon or basket is often performed following EST. EBD may be performed if patients have uncorrected coagulopathies but the risk of pancreatitis is higher than for EST (although the risk of bleeding complications is lower for EBD). ML is often required in difficult to remove CBDS and using this device, CBDS can be removed in 90–95% of cases. Other forms of lithotripsy including laser lithotripsy and EHL are confined to specialised centres and the evidence for their use is based on small studies. ESWL may clear stones from the bile duct in up to 93% of patients but frequently ERC and stone fragment removal is required post ESWL. The role of medical therapy in difficult to remove CBDS (or in CBDS in patients with severe co-morbid illness preventing ERC + stone removal) is still currently uncertain due to a lack of large randomised control trials.     

肠内营养在慢性阻塞性肺病机械通气治疗与护理中的作用

目的　探讨肠内营养对慢性阻塞性肺病 (COPD)机械通气治疗与护理中的作用。方法　行机械通气的2 8例患者随机分为 2组 ,治疗组 14例给予安素营养 4周 ,对照组 14例给予一定量糖、脂肪、氨基酸等常规输液 ,上述两组病人每周常规测定血清蛋白 (ALB)、IgA、IgG、IgM、FEV1、PaO2 、PaCO2 及一次脱机成功率。结果　治疗 2周末实验组ALB、IgA、IgG、IgM均显著高于对照组 (P <0 0 5 ) ;治疗 4周末治疗组所有指标均显著高于对照组 (P <0 0 5 )。结论　肠内营养是COPD机械通气患者的一项重要治疗措施 ,良好细致的护理是保证其成功实施的关键     

复合树脂预热的研究现状和临床应用

复合树脂作为临床常用牙科充填材料存在耐磨性差、聚合收缩大和牙本质边缘适应性不佳等问题。近年有研究发现预热可以改善复合树脂的性能,本文就预热复合树脂对其单体转化率、边缘微渗漏、机械性能以及牙髓的影响等方面进行探讨,以供临床参考。     

机械通气病人吸痰吸引负压研究现状

介绍了国内外机械通气病人吸痰时吸引负压的选择。提示护士在机械通气病人护理过程中应根据病人的具体情况合理选择。     

治疗老年重症呼吸衰竭42例临床分析

目的：探讨机械通气联合支气管肺泡灌洗（BAL）在治疗老年重症呼吸衰竭的作用。方法：选择常规治疗后病情无缓解的重症老年呼吸衰竭患者42例。建立人工气道行钡械通气治疗12～24h后，低氧血症纠正不理想，气道压力偏高，痰多者，应用加温至37℃生理盐水加庆大霉素、地塞米松及爱全乐经纤支镜行BAL，吸除呼吸道粘稠分泌物，每日一次，连续3—5天。结果：42例患者中，37例通气24h，经支气管肺泡灌洗后，气道压力下降，临床症状好转，缺氧及二氧化碳滞留得到改善，病原菌得到明确，成功脱机出院。结论：对老年重症呼吸衰竭在机械通气的基础上联合支气管肺泡灌洗是治疗呼吸衰竭安全有效的重要措施，值得临床应用。     

山莨菪碱对通气机所致大鼠肺损伤防护作用的实验研究

目的 研究山莨菪碱(ADM)对大鼠通气机所致肺损伤(VILI)的防护作用.方法 将36只健康雄性SD大鼠随机分为3组,实施麻醉和气管切开后,吸入空气进行机械通气,通气时间均为4h.A组为对照组,进行常规通气,潮气量8ml/kg,呼吸频率40/min;B组为致伤组,进行大潮气量通气,潮气量40ml/kg,呼吸频率20/min;C组为ADM防护组,分别在通气开始前24、12h及通气开始后0h经尾静脉注射ADM(15mg/kg),潮气量和呼吸频率同B组.每小时行1次动脉血气分析.行支气管肺泡灌洗液(BALF)中的中性粒细胞计数,测定左肺湿/干(W/D)值,血清和BALF中TNF-α、IL-1β水平,血清和肺组织中丙二醛(MDA)、超氧化物歧化酶(SOD)水平,观察肺脏的组织病理学改变.结果 B组大鼠氧合指数(PaO2/FiO2)较A、C组显著下降,BALF中性粒细胞计数显著增加,左肺W/D值较A、C组显著升高.B组大鼠血清和BALF中TNF-α、IL-1β水平较A组显著增高,而C组较B组显著降低.C组大鼠血清和肺组织中MDA水平较B组显著下降,而SOD水平较B组显著升高.组织病理学显示B组大鼠肺脏内较A、C组有更多的中性粒细胞浸润和肺泡壁结构的破坏.结论 ADM通过其抗炎和抗氧化作用对大鼠VILI起防护作用.     

Acute Renal Failure after Lung Transplantation: Incidence, Predictors and Impact on Perioperative Morbidity and Mortality

The incidence, predictors and clinical significance of acute renal failure (ARF) after lung transplantation are not well described. We retrospectively collected data on 296 patients transplanted at our center between April 1992 and December 2000; follow-up was extended until December 2002. Patients were initially divided into two groups: ARF (doubling of baseline creatinine within 2 weeks after surgery) and NoARF. The ARF group was subdivided into ARFD (dialyzed) and ARFnD (not dialyzed). The incidence of ARF was 56% (166/296), but most cases were ARFnD (n = 143). Independent predictors of ARFD (n = 23) were: baseline GFR (OR 0.98, CI 0.96-0.99, p = 0.012), pulmonary diagnosis other than COPD (OR 6.80, CI 1.5-30.89, p = 0.013), mechanical ventilation > 1 d (OR 6.16, CI 1.70-22.24, p = 0.006) and parenteral amphotericin B use (OR 3.04, CI 1.03-8.98, p = 0.045). Both ARFnD and ARFD were associated with longer duration of mechanical ventilation, increased hospital stay and increased early mortality. One-year patient survival was 92.3%, 81.8% and 21.7% in the NoARF, ARFnD and ARFD groups, respectively (p < 0.0001). After controlling for important covariates, ARFD remained associated with an increased hazard of dying (HR 6.77, CI 4.00-11.44, p < 0.0001). In conclusion, ARF occurs commonly after lung transplantation and affects important clinical outcomes, especially when dialysis is required.     

化疗药物性静脉炎及渗漏损伤的动物实验模型研究概况

化疗药物性静脉炎及渗漏损伤的动物实验模型是研究体内化疗药物性静脉炎及渗漏损伤的发病机制和评价各种治疗方法的重要条件。化疗药物性静脉炎及渗漏损伤的实验研究进展缓慢,其主要原因是缺乏理想的动物模型。依文献报道,化疗药物性静脉炎模型主要以大白兔耳缘静脉注射长春瑞滨等化疗药物为多见,化疗药物渗漏损伤模型主要以大鼠及大白兔背部皮下注射盐酸阿霉素等化疗药物为多见。文章就近年来常用的一些化疗药物性静脉炎及渗漏损伤的动物模型综述如下。