经吻合器直肠下端黏膜环形切除肛垫悬吊术治疗脱垂性痔

目的　探讨利用吻合器通过切除直肠下端黏膜 ,肛垫悬吊治疗脱垂性痔的手术疗效和安全性。方法　应用该术式治疗 31例Ⅲ、Ⅳ度环形脱垂痔患者 ,男 18例 ,女 13例 ,平均年龄 49岁 ,痔脱垂病史 7年 ,11例曾接受硬化剂治疗 ,3例有手术治疗史。结果　 2 1例术后立即完全回缩 ,8例术后第 3天后完全回缩 ,2例未能完全回缩。无术后肛门疼痛及肛门部水肿 ,无吻合口出血、尿潴留。术后平均住院 4d ,随访 2～ 2 4个月。术后无大便失禁、肛门狭窄、复发。结论　经吻合器直肠下端黏膜环形切除肛垫悬吊术治疗脱垂性痔具有疗效显著、手术后并发症少、住院时间短等特点。     

一种LDL吸附剂载体-聚丙烯酰胺微球的合成及应用

研究用于低密度脂蛋白 (L DL)吸附的聚丙烯酰胺微球载体的合成工艺、结构特性及吸附 L DL 的性能 ,为进一步研发 L DL 吸附剂载体提供实验依据。采用反相悬浮聚合法按一定的配方合成聚丙烯酰胺微球载体 ,通过扫描电镜、图像分析仪、X光小角散射等手段对其结构特性 (粒径、孔径等 )进行表征 ;同时在微球上固定丝氨酰 -天冬氨酰 -谷氨酸 (SDE)三肽配体制成 L DL 吸附剂 ,通过体外静态吸附对其吸附性能进行了初步研究。结果表明微球粒径为 14 2 .1μm,孔径为 119.8nm,符合作为 L DL 吸附载体的需要 ;在交联剂与单体总量一定的条件下 ,微球孔径随着交联剂用量的增加而减小 ;合成的聚丙烯酰胺微球对 L DL 的非特异性吸附很小 ,而在其上偶联配体制成吸附剂后 ,又表现出对 L DL 的特异性吸附。本实验合成的聚丙烯酰胺微球是一种有效的 L DL 吸附剂载体。     

Changes in fibre-type composition and myosin heavy-chain IId isoform in rat soleus muscle during recovery period after hindlimb suspension

We examined the changes in myosin heavy-chain (HC) isoforms and fibre-type composition in rat soleus muscle using both myosin adenosine triphosphatase staining and sodium dodecyl sulphate/polyacrylamide gel electrophoresis (SDS-PAGE) analyses during the recovery period after 4 weeks of hindlimb suspension. Although there was no change in type IIc fibres after the suspension, an increase in this type of fibres was observed during the 1- to 4-week recovery period. The increase in type Ilc fibres was considered to be due to a shift from type Ila to IIc fibres. The SDS-PAGE analysis revealed the presence of the HC IId isoform, which was not observed in the control muscle, after a 4-week hindlimb suspension. The HC IId isoform gradually decreased over 3 weeks of recovery and disappeared in the 4th week of recovery after the suspension. These results suggest that the hypogravity conditions induced by hindlimb suspension stimulated the synthesis of the HC IId isoform, whereas an increase in mechanical load to the muscle accelerated the degradation of the HC IId isoform and the synthesis of type Ilc fibres during the recovery period after hindlimb suspension.     

The fourth-generation centrifugal blood pump

 The NEDO Gyro permanently implantable (PI) centrifugal blood pump has been developed as a simple, durable, centrifugal blood pump without a complex magnetic suspension system. In vitro studies were performed using a Gyro PI pump with the transparent pump housing in a mock circuit. These studies revealed that the impeller transfers to a floating or a top contact condition, which was dependent on the revolutions per minute (RPM). This pump can be easily converted from a left ventricular assist device (LVAD) to a right ventricular assist device (RVAD) by simply adding a spacer between the pump and the actuator. In order to optimize the impeller suspension for the LVAD and RVAD, spacers of the proper thickness are inserted between both of the pumps and the actuators to regulate the magnetic force. Two Gyro PI pumps were implanted in a bovine model in a 3-month biventricular assist device (BVAD) animal study. This experiment was electively terminated 90 days after implantation. All of the parameters, including pump flow rate, power consumption, and plasma free hemoglobin, were in acceptable ranges. No thrombus formation was observed in either pump. Antithrombogenesis and effectiveness were demonstrated in this animal study. The NEDO Gyro PI pump is ready to move on to the 3-month preclinical system evaluation. Received: February 28, 2002 / Accepted: May 30, 2002 Acknowledgment The New Energy and Industrial Technology Development Organization (NEDO) under the Ministry of Economy, Trade and Industry of Japan financially supported this project. Correspondence to:S. Ichikawa     

243例健康人血红细胞悬浮液射频介电特性的研究

本文应用同轴传输线反射法建立的细胞悬浮液介电测量系统，测量了２４３例健康人（男１２０，女１２３名）血红细胞悬浮液在１～５００ＭＨｚ频率范围的介电常数和电导率。结果表明不同性别和不同血型之间的红细胞悬浮液的介电参数无显著差异。将１９～８０岁之间的受试者按１０岁年龄间隔分成六个组，探讨年龄差别对介电参数的影响；发现５０岁左右是人红细胞介电参数有显著差异的临界年龄，４９岁后三个高年龄组的介电参数显著地低于４９岁前的三个低年龄组的数值（Ｐ＜０．０５）。本文的结果证明年龄对人血红细胞的介电参数有明确的影响。     

Sympathetic nervous activity and cardiovascular variability after a 3-day tail suspension in rats

The effects of a 3-day tail suspension on central and peripheral sympathetic activity were studied in rats by determining the in vivo noradrenaline (NA) turnover in the brain cell groups involved in central blood pressure control (A1, A2, A5 and A6) and in two peripheral organs, heart and kidneys. In addition, cardiovascular parameters and their variabilities were investigated by recording blood pressure (BP) and heart rate (HR) before and after suspension. These measurements were processed by spectrum analysis to assess the influence of tail suspension on autonomic balance. The NA turnover in the suspended rats was markedly reduced in A2 (–49%, P<0.01) and A5 (–38%, P<0.01) nuclei but unchanged in A1 and A6 cell groups compared with the control rats. Peripheral NA turnover was decreased in cardiac atria (–44%, P<0.001) and ventricles (–27%, P<0.01) while it was unchanged in kidneys after suspension. The BP, HR and their variabilities were similar in both groups of animals and showed no changes after suspension compared with baseline values. Spectrum analysis of BP and HR in our conscious suspended rats revealed no changes in power spectrum density or in peak frequencies. The discrepancy between the decrease in central sympathetic activity and the absence of changes in cardiovascular parameters after tail suspension raises the question of the validity of the tail suspended rat model when studying the cardiovascular deconditioning observed in humans after an exposure to actual or simulated weightlessness.     

尾部悬吊大鼠胸主动脉、肺动脉超微结构变化的动态观察

目的观察模拟微重力时大小循环动脉血管超微结构重塑随时间变化的差异,为微重力后立位耐力降低的机制研究积累资料。方法用透射电镜观察-30°尾部悬吊7d(TS7组)、14d(TS14组)及对照组大鼠胸主动脉、肺动脉壁超微结构的变化。结果TS7组胸主动脉内皮细胞表面出现绒毛状突起,部分线粒体空泡变性,内皮下基膜有分层,内弹力板较厚,且厚度不均匀,内弹力板下出现大量的胶原纤维;TS14组胸主动脉内皮细胞变性较明显,部分内皮细胞基质致密化,基膜复层化,内弹力板有破碎,弹力纤维增多。TS7组肺动脉部分内皮细胞突起,细胞内出现脂滴,内皮细胞基膜出现分层状改变,弹力板变薄、断裂,其下方可见收缩型平滑肌及合成型平滑肌细胞;TS14组肺动脉内皮细胞空泡变性较明显,内弹力板未见明显改变,弹力板内外均可见较多的胶原纤维和弹力纤维,内弹力板下方以收缩型平滑肌为主。结论TS7组大鼠胸主动脉和肺动脉出现损伤和增殖并存,以肺动脉较明显;TS14组肺动脉趋于形成新的稳定结构,而胸主动脉新稳定结构还未形成。模拟微重力时大小循环血管发生了结构重塑,大小循环血管重塑的时间过程不同归因于模拟微重力初期由下体转移而来的体液进入大小循环高峰期的时间差。     

Effects of fixed-interval duration on the development of tolerance to decreased responding byl-nantradol

The effects of several types of antidepressants in a recently developed behavioural despair model, the tail-suspension test, are described. Drug effects on the automatically recorded duration of immobility and power of movements were measured in three strains of mice. Only in one strain (NMRI) did almost all antidepressants tested showed the expected reduction in duration of immobility. Tranquillizing drugs, but not stimulants, could be distinguished from antidepressants. The power of movements could not definitively be related to the pharmacological profile of the drugs tested. The use of the tail-suspension test as a rapid and highly predictive behavioural primary screen for antidepressant drugs is suggested.     

两种通气方式在支撑喉镜术中通气效果的临床观察

目的　比较细气管导管下 ,HFJV与IPPV在支撑喉镜声带息肉摘除术中的通气效果 ,以根据具体情况选择通气方式。方法　随机选择 4 0例ASAⅠ～Ⅱ级声带息肉病人 ,拟行支撑喉镜术 ,随机分为两组 ,HFJV组和IPPV组 ,每组 2 0例。数据均以X±S表示 ,采用t检验。结果　HFJV组和IPPV组手术时间分别为 10 .2± 1.6分钟、10 .1± 1.4分钟 ,无明显差异 (P >0 .0 5 )。HFJV以 6 0次 /分的频率、15 0kPa压力通气 ,术毕CO2 和PH值有显著升高趋势 (P <0 .0 5 ) ;IPPV以 12次 /分的频率、10ml/kg潮气量通气 ,术毕CO2 也有升高趋势 ,但无明显差异 (P >0 .0 5 )。明显低于HFJV组 (P <0 .0 5 )。两组PaO2 明显升高 (P <0 .0 1) ,但两组无显著差异 (P >0 .0 5 )。结论　无论是HFJV还是IPPV ,都能供氧充足 ,满足机体所需 ,但IPPV更易于CO2 排出。因此对于短时间声带息肉支撑喉镜下摘除术控制通气时 ,HFJV与IPPV均可采用 ,而对于肥胖或胸肺顺应性差的病人 ,IPPV更适宜