嗅黏膜嗅鞘细胞与肌基膜管联合移植修复脊髓损伤

目的:观察嗅黏膜来源的嗅鞘细胞与肌基膜管联合移植后对脊髓损伤的修复效果。方法:1只SD大鼠行背正中切口,顺椎旁肌纤维切除约1.5cm×0.8cm×0.6cm的肌条,复温、漂洗并挤压肌条以排出肌浆,制成肌基膜管。4只SD大鼠麻醉后取出嗅黏膜,胶原酶消化法分离培养嗅鞘细胞,调整浓度至1011L-1。取SD大鼠50只,随机分成5组:嗅鞘细胞 肌基膜管联合组、嗅鞘细胞组、肌基膜管组、模型组、正常组,10只/组。除正常组外,其余组均建立脊髓损伤模型,于T10横断脊髓并切除约2mm,将培养7d的嗅鞘细胞与肌基膜管按组别分别植入脊髓断端,模型组用浸有DMEM的凝胶海绵桥接横断的脊髓。结果:移植后第8周,嗅鞘细胞 肌基膜管联合组、嗅鞘细胞组大鼠运动功能明显恢复,出现大关节大幅度运动,且前者运动功能BBB评分升高尤为显著(P<0.01);肌基膜管组大鼠仅见小关节轻微活动;模型组大鼠后肢挛缩重,无明显功能恢复。嗅鞘细胞 肌基膜管联合组后肢体感诱发电位及运动诱发电位的潜伏期显著低于其他各组(P<0.01)。苏木精-伊红染色和核转录因子免疫组化染色结果显示,嗅鞘细胞 肌基膜管联合组、嗅鞘细胞组的移植物与损伤脊髓整合较好,未见明显空洞,有大量染色呈阳性的纤维,纤维较长,由近侧端长入远侧端;肌基膜管组有空洞形成,染色阳性的纤维数量少,纤维细小且排列紊乱;模型组端断间充满瘢痕组织,未见明显染色阳性纤维。结论:嗅鞘细胞移植可促进脊髓损伤后的轴突再生,肌基膜管作为一种生物管道,两者联合应用可明显促进脊髓损伤后的轴突再生及功能恢复。     

多种神经组织修复成鼠脊髓损伤的实验研究

背景脊髓损伤后以游离周围神经片断(雪旺氏细胞)与胚胎脊髓联合移植能协同诱发宿主再生潜能,而带血管蒂周围神经移植后有更多的雪旺氏细胞存活,但其与胚胎脊髓协同作用的研究较少.目的探讨不同神经组织移植修复成鼠急性脊髓损伤的能力.设计单盲随机对照实验.地点和对象实验在解放军第三军医大学大坪医院全军战创伤中心骨创伤科完成,研究对象为150只4月龄雌性Wistar属成年大鼠,由解放军第三军医大学实验动物中心提供.干预成鼠胸髓损伤后,分别移植游离正中神经(FPN组)、带血管蒂正中神经(VPN组)、孕14天胚胎脊髓(FSC组)、游离正中神经加胚胎脊髓(P+F组)、带血管蒂正中神经加胚胎脊髓(V+F组).主要观察指标术后8周行神经解剖及电生理检查.结果V+F组再生轴突和存活雪旺氏细胞数目、胚胎脊髓体积增长速度和神经元密度显著高于对照组(P＜0.01),细胞分化较好,突触较成熟o SEP的P1,N1波潜伏期显著缩短(P＜0.01).结论带血管蒂周围神经与胚胎脊髓联合移植,在解剖和电生理上均优于其他组织,对FSC的生长发育及损伤神经元的再生能力均有一定的促进作用.     

多种神经组织修复成鼠脊髓损伤的实验研究

背景：脊髓损伤后以游离周围神经片断(雪旺氏细胞)与胚胎脊髓联合移植能协同诱发宿主再生潜能，而带血管蒂周围神经移植后有更多的雪旺氏细胞存活，但其与胚胎脊髓协同作用的研究较少。目的：探讨不同神经组织移植修复成鼠急性脊髓损伤的能力。设计：单盲随机对照实验。地点和对象：实验在解放军第三军医大学大坪医院全军战创伤中心骨刨伤科完成，研究对象为150只4月龄雌性Wistar属成年大鼠，由解放军第三军医大学实验动物中心提供。干预：成鼠胸髓损伤后，分别移植游离正中神经(FPN组)、带血管蒂正中神经(VPN组)、孕14天胚胎脊髓(Fsc组)、游离正中神经加胚胎脊髓(P+F组)、带血管蒂正中神经加胚胎脊髓(V+F组)。主要观察指标：术后8周行神经解剖及电生理检查。结果：V+F组再生轴突和存活雪旺氏细胞数目．胚胎脊髓体积增长速度和神经元密度显著高于对照组(P&;lt;0．01)，细胞分化较好，突触较成熟。SEP的P1，N1波潜伏期显著缩短(P&;lt;0．01)。结论：带血管蒂周围神经与胚胎脊髓联合移植，在解剖和电生理上均优于其他组织，对FSC的生长发育及损伤神经元的再生能力均有一定的促进作用。     

超长时间热缺血对大鼠提睾肌损伤的组织及形态学变化观察

目的:探讨肌瓣超长时间热缺血后,再灌注期微静脉的形态学和组织学变化,及其对微循环和组织细胞的影响,以期了解超长时间缺血肌肉组织严重损伤的原因。方法:以体质量180～220g雄性SD大鼠,制成大鼠提睾肌缺血-再灌注模型(热缺血5h,再灌注2h),观察缺血-再灌注期肌瓣微循环形态学和组织学的变化。结果:①缺血5h后,微动脉于再灌注期出现明显痉挛并伴随血流速度的减缓;而伴行的微静脉扩张,流速明显变缓,局部形成附壁血栓,部分微静脉出现原发或继发性无复流现象,局部微静脉回流障碍。②组织学检查提示,再灌注期微静脉内壁可见大量的中性粒细胞黏附,而动脉内未见明显的附壁白细胞;局部可见附壁血栓,血管周围组织内可见游出的中性粒细胞;透射电镜检查也提示血管内皮细胞明显受损伤。③再灌注期微静脉回流障碍,局部形成一种“只灌不流”的病理现象,出现继发性静脉缺血,使肌瓣组织出现大片明显的漏出性出血,加重组织细胞的损伤。结论:再灌注期微静脉继发性缺血和随即形成的漏出性出血可能是肌肉组织超长时间缺血后严重损伤的重要因素。     

腹内斜肌神经肌瓣移植治疗晚期面瘫患者的护理

目的探讨带血管及多神经蒂的游离腹内斜肌瓣移植治疗晚期面瘫患者的护理要点。方法总结采用带血管及多神经蒂的游离腹内斜肌瓣移植治疗晚期面瘫患者48例的治疗及护理要点。结果48例患者伤口一期愈合率为100％,肌瓣成活率为100％,手术后未发生并发症,术后10～14周开始恢复肌肉运动功能。结论术前加强心理护理、手术准备充分,术后严密观察、加强饮食指导及功能锻炼,是手术成功和患者康复的保障。     

带蒂大网膜脊髓移植术的护理

带蒂大网膜脊髓移植术,是将带血管蒂的大网膜自腹腔游离,经胸、腹壁皮下隧道引至脊髓腔,覆盖于脊髓表面,通过侧支循环的建立,促使病人的脊髓功能逐渐恢复。手术主要适用于急性脊髓损伤造成截瘫及作椎板减压术后无效或疗效不够满意的病人。我院同外院合作自1983年6月至1985年6月,共为23例病人开展了大网膜脊髓移植     

带血管蒂周围神经在联合移植修复脊髓损伤中的作用

目的探讨带血管蒂周围神经促进胚胎脊髓修复成鼠脊髓损伤的能力。方法成鼠胸段脊髓损伤后,分别移植带血管蒂正中神经(VPN组)、孕14天胚胎脊髓(FSC组)、带血管蒂正中神经加胚胎脊髓(V+F组)。术后8周行组织学及电生理检查。结果V+F组移植神经与脊髓连接紧密,有较多新生轴突长入,雪旺氏细胞大量存活和增殖,神经丝蛋白、100％饱和硫蛋白阳性反应均明显高于VPN组(P＜0.01);胚胎移植物与受体融合佳,体积增长速度、神经纤维和神经元数目显著高于FSC组(P＜0.01),大部分细胞分化较好,突触较成熟;SEP检查示P1、N1波波伏期显著缩短(P＜0.01)。结论带血管蒂周围神经与胚胎脊髓联合移植,对FSC的生长发育、对损伤神经元的再生能力均有一定的促进作用。     

超长时间热缺血对大鼠提睾肌损伤的组织及形态学变化观察

目的：探讨肌瓣超长时间热缺血后，再灌注期微静脉的形态学和组织学变化，及其对微循环和组织细胞的影响，以期了解超长时间缺血肌肉组织严重损伤的原因。方法：以体质量180-220g雄性SD大鼠，制成大鼠提睾肌缺血-再灌注模型(热缺血5h，再灌注2h)，观察缺血-再灌注期肌瓣微循环形态学和组织学的变化。结果：①缺血5h后，微动脉于再灌注期出现明显痉挛并伴随血流速度的减缓；而伴行的微静脉扩张，流速明显变缓，局部形成附壁血栓，部分微静脉出现原发或继发性无复流现象，局部微静脉回流障碍。②组织学检查提示，再灌注期微静脉内壁可见大量的中性粒细胞黏附，而动脉内未见明显的附壁白细胞；局部可见附壁血栓，血管周围组织内可见游出的中性粒细胞；透射电镜检查也提示血管内皮细胞明显受损伤。③再灌注期微静脉回流障碍，局部形成一种“只灌不流”的病理现象，出现继发性静脉缺血，使肌瓣组织出现大片明显的漏出性出血，加重组织细胞的损伤。结论：再灌注期微静脉继发性缺血和随即形成的漏出性出血可能是肌肉组织超长时间缺血后严重损伤的重要因素。     

大鼠臂丛神经损伤后脊髓运动神经元再生轴突的路径

目的:观察臂丛神经不同损伤后脊髓前角运动神经元再生轴突的路径选择,探讨运动功能恢复与再生的关系。方法:选用60只健康成年雄性SD大鼠,随机分为5组:根性切断组、根性挫伤组、干性切断组、干性挫伤组和对照组。术后2个月进行Grooming实验,检测其患肢运动功能的恢复。肌皮神经肌支或皮支注射荧光金逆行追踪标记,3天后取脊髓C5-7节段标本,计数再生脊髓运动神经元数。结果:各组肌支标记的神经元数均远多于皮支。运动功能恢复4级以上百分比,根性切断组(0)<根性挫伤组(17%)<干性切断组(50%)<干性挫伤组(75%)<对照组(100%)。结论:臂丛神经损伤后脊髓前角运动神经元再生轴突的路径为肌支路径。不同损伤后功能恢复的程度不同,其与再生轴突的路径及再生轴突的数量有关。     

大鼠急性脊髓损伤后神经细胞凋亡与血管内皮细胞的关系

目的:观察大鼠急性脊髓损伤后凋亡相关蛋白Bax和Bcl-2在邻近节段血管内皮细胞中的表达。探究脊髓继发性损伤中神经细胞凋亡的原因。方法:成年Wistar大鼠40只,随机分为正常对照组,假手术组及脊髓压迫组。于手术后6,24,72h,7,14,28d取以损伤部位为起点头侧端脊髓1.5cm,采用电镜观察超微结构变化;以免疫组织化学技术检测Bax及Bcl-2的表达;以TUNEL法检测细胞的凋亡。结果:正常组及假手术组Bax和Bcl-2在血管内皮细胞中只有少量表达,压迫组于伤后6h出现Bax在血管内皮细胞中的强阳性表达,伤后3d达到高峰,一两周下降,4周时只有少数阳性细胞。电镜观察,内皮细胞有不同程度的细胞膜起泡,染色体边集,细胞凋亡。结论:在急性脊髓损伤后的继发损伤过程中,神经细胞的凋亡可能是血管内皮细胞损伤的结果。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.