高原低氧应激对兔睾丸组织的损害

目的 观察高原不同海拔地区低氧应激对兔睾丸组织及生精的损害.方法 将平原兔12只随机分为4组,每组3只.A组为对照组,B、C、D组为平原兔在48 h内直接迁饲到海拔4320 m后,1、7、30 d组.随机将6只饲养在海拔2260 m高原兔分为2组,每组3只.E组为高原对照组,F组为高原兔24 h内迁饲到4320m后1 d.各组宰杀后行睾丸组织病理学观察.结果 从平原急进高原4320 m地区后,病理检查发现,睾丸组织内大部分曲细精管的各级生精细胞减少,以初级母细胞减少明显;精子细胞明显减少,与对照组比较差异有统计学意义(P<0.05),睾丸间质内血管充血,间质细胞明显减少,无成堆现象.曲细精管内细胞计数C、D组分别为390.40±158.94、580.80±167.32,A组868.80±293.98(P<0.05).精子密度减少,C、D组分别为0.0027±0.0011、0.004±0.0017,A组0.006±0.002(P<0.05).曲细精管内生精细胞与支持细胞的比率降低,支持细胞计数A、B、C、D、E、F组分别为113、191、187、48、112、162.曲细精管内生殖细胞与支持细胞比率:A、B、C、D、E、F组分别为7.69、6.91、2.09、12.10、8.54、5.26,与对照组比较差异有统计学意义(P<0.05).结论 从平原急进高原地区可致兔睾丸组织受损,表现为各级生精细胞及间质细胞减少.当大气氧分压突然较大幅度降低时,不同大气压环境下生存的动物引起睾丸组织损害的病理组织学改变大致相同.     

一种新型动脉栓塞剂的动物实验研究

目的探寻新型可显影终末型永久性血管栓塞剂。方法采用自行研制的聚N-取代丙烯酰胺凝胶作为栓塞剂对10只犬行肾动脉栓塞术，观察使用状况和栓塞效果。结果10只犬肾动脉栓塞术均获成功。病理检查：栓塞2d肾脏呈急性栓塞性梗死，7～10d肾脏呈弥漫性梗死，1～3个月肾脏显著萎缩，广泛纤维化及瘢痕形成。新型栓塞剂流动性好，易于推动，并可在X线下清晰显影。结论聚N-取代丙烯酰胺凝胶是一种可显影、易于观察栓塞效果及返流情况、栓塞效果确切的终末型永久性栓塞剂。     

精氨酸锌作为一种化学绝育剂的研究

本研究采用精氨酸锌及生理盐水,分别经80只正常性成熟Winstar大鼠的附睾尾注射0.1m1,观察48小时、1周、2周,3周及4周以后火鼠睾丸、附睾、输精管、前列腺的病变,结果显示经上述两种物质注射1周以后,睾丸均出现生精功能低下,间质细胞无异常,其精氨酸锌注射两周后,附睾尾管腔内即达到完全无精子,而生理盐水注射后仅导致附睾尾精子数量及活力大大降低,但始终不能达到完全无精子。此结果提示:精氨酸锌附睾尾注射可能成为一种新的男性绝育方法,值得进一步研究。     

HEMA共聚物液体栓塞剂经动脉栓塞兔肾的实验研究

目的探讨HEMA共聚物液体栓塞剂经动脉栓塞实质脏器的可行性、安全性和效果。方法应用HEMA共聚物液体栓塞剂经动脉栓塞6只新西兰大白兔单侧肾脏,术后分别于急性期(栓塞后1~3天)和慢性期(栓塞后8周、12周)复查血管造影表现,CT平扫观察栓塞剂沉积和肾脏形态。光镜观察栓塞血管内及周围肾脏组织病理变化。结果 6只兔单侧肾脏均成功栓塞并存活。栓塞术后检查微导管,见导管完整、内壁光滑、无栓塞剂黏附。复查显示栓塞剂在肾实质内沉积良好,栓塞血管无再通。栓塞后急性期处死3只动物,栓塞血管内膜完整,无坏死,管腔内大量中性粒细胞和单核细胞浸润,肾小球、肾小管呈灶状坏死;栓塞后慢性期处死3只动物,肾小球、肾小管大量萎缩、纤维化、玻璃样变。结论HEMA共聚物液体栓塞剂在X线下显影良好,黏度低不粘管,兼容常用市售微导管并易于注射,栓塞效果稳定持久,血管无再通,适于栓塞实质脏器。     

一种快速、简便的皮下埋植剂取出方法

一种快速、简便的皮下埋植剂取出方法张桂英张婉萍张淑芹自１９９４年４月至１９９６年５月，我们对标准的皮下埋植剂取出方法进行了改进，并用改进后方法取出１２３例，效果满意，现将方法介绍如下。１．手术器械：消毒钳一把，肾型盘一个，２ｍｌ注射器一支，５及７号针...     

低氧诱导的大鼠系膜细胞增殖及基质mRNA表达的研究

目的观察慢性低氧诱导的系膜细胞增殖，细胞外基质ｍＲＮＡ表达及蛋白激酶Ｃ（ＰＫＣ）在低氧介导系膜细胞增殖中的作用。方法采用体外大鼠系膜细胞培养，Ｎｏｒｔｈｅｒｎｂｌｏｔ分析及放射核素测定法。结果与正常氧（１８％Ｏ２）比较，低氧（３％Ｏ２）培养系膜细胞３Ｈ－胸腺嘧啶掺入率显著增高（３．３±０．３×１０３ｍｉｎ－１／瓶对１．７±０．２×１０３ｍｉｎ－１／瓶，Ｐ＜０．０１）。细胞计数在培养２８小时无显著差异，但培养７２小时，低氧比正常氧培养增加３３％（Ｐ＜０．０１）。低氧培养系膜细胞表达Ⅳ型前胶原（ＰＣｏｌⅣ）、纤维连接蛋白（Ｆｎ）、层粘连蛋白（Ｌａ）ｍＲＮＡ显著增高。测定低氧培养系膜细胞ＰＫＣ活力呈双峰型增高，加入ＰＫＣ抑制剂Ｈ７可抑制低氧诱导的系膜细胞增殖。结论慢性低氧可诱导系膜细胞增殖和细胞外基质产生增多，ＰＫＣ激活起着重要的介导作用     

低氧及运动致大鼠骨骼肌形态学改变的实验研究

目的观察低氧及低氧复合运动时,大鼠体重及腓肠肌显微、超微结构的变化,旨在探讨低氧状态下适当运动对骨骼肌的影响。方法建立大鼠低氧及低氧复合运动模型,运用光镜及透射电镜观察大鼠腓肠肌显微、超微结构的变化。结果低氧复合运动组较低氧安静组大鼠体重差异有显著性意义(P<0.05)。低氧复合运动组骨骼肌结构正常,线粒体数量增加,骨骼肌纤维增粗,毛细血管增生。结论低氧复合适当的运动能够维持骨骼肌的正常形态,增强骨骼肌的有氧代谢,起到保护骨骼肌的作用,从而提高骨骼肌的低氧适应能力,促进低氧习服。     

微管干预剂对缺氧心肌细胞糖酵解途径关键酶的影响

目的 了解微管干预剂对缺氧心肌细胞糖酵解途径关键酶的影响. 方法体外培养心肌细胞,分为单纯缺氧组、缺氧+微管解聚剂(秋水仙碱)组、缺氧+低浓度微管稳定剂组、缺氧+中浓度微管稳定剂组、缺氧+高浓度微管稳定剂组,后3组加入的微管稳定剂为紫杉醇,浓度分别为5、10、15 μmol/L.采用激光共聚焦显微镜观察微管形态学变化,检测细胞活力及己糖激酶、丙酮酸激酶、磷酸果糖激酶、乳酸脱氢酶的活性. 结果缺氧+微管解聚剂组和缺氧+高浓度微管稳定剂组心肌细胞微管结构破坏显著,细胞活力亦明显下降[缺氧1.0 h,2组细胞活力分别为(89.99±3.47)%、(84.56±6.61)%,明显低于单纯缺氧组(97.44±1.76)%(P<0.01)],前3种酶的活性亦明显降低;缺氧+低浓度微管稳定剂组前3种酶的活性与单纯缺氧组基本近似;缺氧+中浓度微管稳定剂组微管结构损伤显著轻于其他组,前3种酶的活性于缺氧6.0 h内高于单纯缺氧组.缺氧后各组乳酸脱氢酶活性升高. 结论适当浓度的微管稳定剂能明显减轻微管结构损伤,促使缺氧早期心肌细胞糖酵解酶活性增强.     

3种脱敏剂对牙本质粘结强度的比较研究

目的:探讨GLUMA、Bi f l uor i dT12和MS COAT 3种脱敏剂处理牙本质,对牙本质粘结界面粘结强度的影响。方法:人离体前磨牙20颗,去除咬合面釉质,随机分成4组(n=5):A组(GLUMA)、B组(Bi fl uori dT12)、C组(MS COAT)、D组(空白)。A、B、C组分别使用相应脱敏剂在牙本质表面处理,D组不处理。全部样本3M ESPE Adper TM自酸蚀树脂粘结剂粘结,复合树脂修复厚约4～5mm,硬组织切片机制成1.0mm×1.0mm×8.0mm长方体试样,微拉伸测试仪测试粘结强度并进行统计学分析。结果:A组微伸拉强度高于对照组,但无统计学意义(P>0.05);B和C组低于对照组,有统计学意义(P<0.05)。结论:GLUMA脱敏剂预处理牙本质的粘结强度最强。     

硫喷妥钠对上肢短潜伏期体感诱发电位的影响

目的与方法：７例上肢感觉传导道无异常的病例,静脉注射硫喷妥钠５ｍｇ／ｋｇ后,分别观察注药前、注药后即刻、２、４和６ｍｉｎ上肢短潜伏期体感诱发电位,比较Ｐ１５、Ｎ２０、Ｐ２５各波的潜伏期以及Ｐ１５Ｎ２０、Ｎ２０Ｐ２５的峰间值。结果：各波潜伏期在注药后缩短,以注药后２、４ｍｉｎ最明显,６ｍｉｎ时已基本恢复,Ｐ１５Ｎ２０、Ｎ２０Ｐ２５峰间值在注药后减小,以２ｍｉｎ时减至最小,６ｍｉｎ时已基本恢复。结论：术中行体感诱发电位监测时,不宜使用硫喷妥钠。     

Structural and functional aberrations in the cerebral cortex of tenascin-C deficient mice

The extracellular matrix glycoprotein tenascin-C (TNC) has been implicated in neural development and plasticity but many of its functions in vivo remain obscure. Here we addressed the question as to whether the constitutive absence of TNC in mice affects cortical physiology and structure. Defined major cell populations (neurons and inhibitory neuronal subpopulations, astrocytes, oligodendrocytes and microglia) were quantified in the somatosensory and motor cortices of adult TNC deficient (TNC-/-) and wild-type (TNC+/+) mice by immunofluorescence labelling and stereology. In both areas studied we found abnormally high neuronal density, astrogliosis, low density of parvalbumin-positive interneurons and reduced ratios of oligodendrocytes to neurons and of inhibitory to excitatory neurons in the TNC deficient as opposed to the non-deficient animals. Analysis of Golgi-impregnated layer V pyramidal neurons in TNC-/- animals showed aberrant dendrite tortuosity and redistribution of stubby spines within first- to third-order dendritic arbors. Significantly enhanced responses upon whisker stimulation were recorded epicranially over the barrel and the motor cortices of TNC-/- as compared to TNC+/+ animals, and this effect might be associated with the diminished inhibitory circuitry. These results indicate that TNC is essential for normal cortical development and function.     

术中神经监测技术在脊柱手术中的临床应用

术中神经监测(Intraoperative Neuromonitoring,IOM)伴随着科技和麻醉技术的发展,逐渐被推广并广泛使用,尤其在脊柱手术对脊髓和神经功能的有效监测,降低了手术风险。但在手术的施行过程中,引起监测信号变化的影响因素非常多。本文将对时下常用的几种监测方式进行回顾,并进一步讨论和分析在脊柱手术的过程中,监测信号变化的原因。     

体感诱发电位评价家兔脊髓冲击伤模型的神经机能变化

目的 探讨脊髓冲击伤前后的体感诱发电位的变化,评价家兔神经机能的改变程度.方法 应用改良霍普金森杠杆设备根据冲击波的压力不同(0.40 MPa,0.60 MPa,0.80 MPa)建立不同损伤程度的胸T9-T10脊髓冲击伤模型,12 h后用体感诱发电位仪分别计测家兔脊髓冲击伤前后的体感诱发电位,利用分析软件对诱发电位P...     

Safe surgery of lesions near the motor cortex using intra-operative mapping techniques: a report on 50 patients

Summary In 50 patients lesions located in or adjacent to the motor strip were microsurgically removed with the help of intra-operative electrophysiological mapping of the sensorimotor cortex. Mapping consisted of cortical stimulation and/or recording of somatosensory evoked potentials. Depending on the patient's pre-operative neurological status, surprisingly good results could be achieved: The surgery resulted in increased permanent sensorimotor deficit in only 4% of cases and in improved neurological status in 30% of cases.It is concluded that surgical removal of centrally located lesions using a microsurgical technique and intra-operative mapping of the motor cortex is safe and permits extensive or radical resection of lesions, even those in the motor cortex itself.     

Effects of dexmedetomidine on intraoperative motor and somatosensory evoked potential monitoring during spinal surgery in adolescents

Background: Dexmedetomidine may be a useful agent as an adjunct to an opioid–propofol total intravenous anesthesia (TIVA) technique during posterior spinal fusion (PSF) surgery. There are limited data regarding its effects on somatosensory (SSEPs) and motor evoked potentials (MEPs). Methods: The data presented represent a retrospective review of prospectively collected quality assurance data. When the decision was made to incorporate dexmedetomidine into the anesthetic regimen for intraoperative care of patients undergoing PSF, a prospective evaluation of its effects on SSEPs and MEPs was undertaken. SSEPs and MEPs were measured before and after the administration of dexmedetomidine in a cohort of pediatric patients undergoing PSF. Dexmedetomidine (1 μg·kg^?1 over 20 min followed by an infusion of 0.5 μg·kg^?1·h^?1) was administered at the completion of the surgical procedure, but prior to wound closure as an adjunct to TIVA which included propofol and remifentanil, adjusted to maintain a constant depth of anesthesia as measured by a BIS of 45–60. Results: The cohort for the study included nine patients, ranging in age from 12 to 17 years, anesthetized with remifentanil and propofol. In the first patient, dexmedetomidine was administered in conjunction with propofol at 110 μg·kg^?1·min^?1 which resulted in a decrease in the bispectral index from 58 to 31. Although no significant effect was noted on the SSEPs (amplitude or latency) or the MEP duration, there was a decrease in the MEP amplitude. The protocol was modified so that the propofol infusion was incrementally decreased during the dexmedetomidine infusion to achieve the same depth of anesthesia. In the remaining eight patients, the bispectral index was 52 ± 6 at the start of the dexmedetomidine loading dose and 49 ± 4 at its completion (P = NS). There was no statistically significant difference in the MEPs and SSEPs obtained before and at completion of the dexmedetomidine loading dose. Conclusion: Using the above‐mentioned protocol, dexmedetomidine can be used as a component of TIVA during PSF without affecting neurophysiological monitoring.     

Anesthetic induction with thiopental: its effect on scalp topography of median nerve somatosensory evoked potentials

The effects on median nerve somatosensory evoked potentials (SEPs) of analgesic doses of fentanyl, meperidine or morphine and of sodium thiopental (STP) anesthesia (4 mg/kg) were tested in 36 surgical patients. We also explored changes in SEP components as a function of their scalp location. Before and after medication, responses were recorded from the scalp overlying the parietal cortex (ipsi- and contralateral to the stimulated arm) and the precentral (contralateral) cortex. None of the three opiates affected SEP latencies or amplitudes. The barbiturate increased the amplitudes of subcortical and early cortical components (N18, N20, P22, P25), whose latencies, however, were not significantly modified. The effect of STP on later SEP cortical components depended on their scalp topography: parietal N33 and P45 underwent significant changes in both latency and amplitude, whereas precentral N30 showed a significant amplitude increase only. Thiopental anesthesia produces clearer short-latency SEP recordings, from both parietal (components N20-P25) and precentral (P22, N30) areas.     

缺氧预处理对缺血缺氧脑组织超微结构与自由基的影响

目的 观察缺氧预处理对缺血缺氧脑组织超微结构及脑组织自由基的影响。方法 将40只小鼠随机分为4组。A组为盐水对照组,B组为缺氧预处理组,IH组为缺血缺氧组,BIH组为缺氧预处理后缺血缺氧组。各组有6只小鼠分别采用黄嘌呤氧化酶法和硫代巴比妥酸法和硫巴比妥酸法检测脑组织的超氧化物歧化酶（SOD）活性和丙二醛（MDA）含量,另4只小鼠用于透射电镜下脑组织超微结构的观察。结果 与A组比较,B组SOD活性增加,IH组MDA组含量明显增加,而IH组SOD活性明显增加的同时,MDA含量比IH明显降低。电镜显示B组除部分神经元轻度肿胀外,脑组织超微结构基本同A组,IH组细胞核变形,细胞浆成空泡,严重者满视野几乎找不到正常细胞,无损害的神经元＜10％,BIH组细胞结构基本恢复正常,无损伤神经元达63％。结论 缺氧预处理对再缺血缺氧引起的神经元损伤有保护作用,内源性抗氧化物质的增加与其有直接关系。     

腰_5、骶_1皮节刺激节段性体感诱发电位对腰骶神经根病变诊断的价值探讨

１９９２年６月～１９９３年６月对１００例临床诊断腰椎间盘突出的患者进行下肢常规（胫后神经）皮层体感诱发电位（ＣＳＥＰ）检查，同时进行Ｌ_５、Ｓ_１皮节刺激节段性体感诱发电位（ＤＳＥＰ）检查，发现ＤＳＥＰ可提高常规胫后神经ＣＳＥＰ诊断的敏感性及准确性，防止其局限性，为临床诊断提供更可靠依据。