高海拔（2261m）急性习服期大鼠脑内β—EP含量的实验研究（之三）

选用标化成年雄性Wistar大鼠、以放射免疫测定法（RIA），研究了大鼠由平原引入高海拔环境后，在24小时急性司服期，垂体及各脑区内β－内啡肪样免疫活性物质（β－EPLI）的含量变化。结果表明，大鼠引入高海拔环境后脑内β－EP含量发生明显的动态变化。高海拔实验组与平原对照组相比，垂体内β－EP含量降低非常显著（P＜0．01）。纹状体、下丘脑、丘脑、桥延、海马、皮层内β－EP含量增加非常显著（P＜0．01）。中脑内β－EP含量虽然也增加，统计学处理无显著性意义（P＞0．05）。据此推测：大鼠急进高海拔低氧环境后垂体β－EP的分泌与释放受到影响。提示，脑内β－EP参与低氧的应激反应过程，可能作为神经递质和调质，通过神经──内分泌环路在应激反应中起介导作用，β－EP可能为中枢神经系统内调节应激反应的主要应激激素之一。     

模拟高原和返回平原后大鼠心肌血流量的变化

目的：观察缺氧及停止缺氧后对大鼠心肌血流量的影响。方法：３４只Ｗｉｓｔａｒ大鼠，随机分为４组：①平原对照组；②急性缺氧组；③慢性缺氧组；④返回平原组。以放射性生物微球法测定心肌血流量。结果：急性缺氧引起ＰａＯ２、心输出量及氧运送量降低，但左、右心室心肌血流量明显增加；慢性缺氧时右心室收缩压、血球压积、血液粘滞性及右心室生理指数明显增加，而心肌血流量接近正常。停止缺氧３０ｄ后，上述所有指标均与平原以     

Effects of L-Tetrahydropalmatine on NOSⅢ Gene Expression in Hypoxia and Cultured Porcine Cerebral Arterial Endothelial Cells during Reoxygenation

L- Tetrahydropalmatine (L- THP) ,a kind of al-kaloid extracted from traditional Chinese medicineRhizoma corydalis,posseses sedative,analgesic andhypnotic effects.Recently,it has been demonstratedthat L- THPalso had calcium- antagonistic and antiar-rythmic effects.Studies showed that L- THP had aprotective effect on acute focal and global cerebral is-chemia- reperfusion injury[1,2 ] .Many studies provedthat the production of NO wasincreased significantlyduring ischemia- reperfusion.The o…     

高原环境下大鼠对硒制剂耐受力的实验研究

本实验将大鼠从上海空运至兰州，很快转至高海拔地区，用光镜及电镜观察了亚硒酸钠对大鼠的影响。结果发现在高原环境下大鼠对硒的耐受力减低，引起了大鼠猝死半加得高原缺氧对心肌的损伤，降低了大鼠高原适应性。本文还对其耐受机理进行了初步讨论。     

防止银器文物变色的唑系复合缓蚀剂Ⅰ. 缓蚀剂成膜处理工艺与防变色性能的评定

:通过按正交法设计的紫外光照曝露等加速大气腐蚀实验 ,研究了用于防止银变色的唑系复合缓蚀剂成膜处理的工艺 ,并评定其对模拟文物银试片的防变色性能。采用极化曲线和交流阻抗Nyquist图 ,讨论了防变色作用的电化学机理。实验结果表明 ,缓蚀剂 PMTA、MBI和 MBO具有较好的协同作用 ,银试片在 5 0°C、p H 3.0、组分 MBO∶ PMTA∶ MBI为 1∶ 1 .7∶ 3(摩尔比 )、复合缓蚀剂浓度为 0 .0 1 89mol/L的溶液中 4h成膜处理后 ,经 48h硫华气氛和 36h紫外光曝露腐蚀实验 ,无色斑出现 ,表明缓蚀膜明显地提高了银试片的抗变色能力     

Accidental bronchial intubation An analysis of AIMS incident reports from 1988 to 1994 inclusive

Accidental bronchial intubation was examined in the first 3947 cases reported to the Australian Incident Monitoring Study and was found to have accounted for 154 (3.7%) of the total incidents reported. Most incidents were detected in the operating theatre (93.5%) and during maintenance of anaesthesia (77.9%), by unexplained oxygen desaturation alone (63.6%). Capnography remained normal or unremarkable during 88.5% of the episodes. One-third of cases were associated with head or neck surgery and possible flexion of the patient's head. A RAE tube was used in 20% of incidents, a greater frequency than occurred in the study overall. A third party was implicated in 36 (23.4%) of cases. Ninety per cent of cases were considered preventable. Major morbidity occurred in three cases and unplanned intensive care admission was required in a further five. Almost two-thirds (61.1%) of the incidents might have been avoided by the proposed markings on the tracheal tube. We conclude that when arterial desaturation occurs at any stage during anaesthesia the possibility of bronchial intubation must be considered. Asymmetrical ventilation may be difficult to detect clinically and in most cases there is no change in capnography.     

缺氧叠加三氯化铁大鼠肺动脉高压模型肺血管内皮细胞的病理变化

目的 :观察大鼠缺氧叠加静注FeCl3 致肺动脉高压模型肺动脉内皮细胞的病理变化。方法 :常规病理组织学和透射电子显微镜及多功能显微镜观察肺动脉内皮细胞的变化。结果 :缺氧叠加静注FeCl3 2周、4周时肺动脉平滑肌肥厚 ,肺间质有大量炎细胞浸润 ,血小板聚集 ,微血栓形成 ,血管内皮剥脱 ,内膜下组织暴露 ,内膜下及弹力纤维变形 ,内皮细胞成片脱落为循环内皮细胞。结论 :缺氧叠加静注FeCl3 引起的肺动脉内皮细胞脱落 ,内膜下组织暴露 ,微血栓形成和平滑肌肥厚是肺动脉高压形成的病理学基础     

缺氧诱导因子-1α在去势前后大鼠腹叶前列腺中表达的变化

目的探讨与缺氧相关的缺氧诱导因子-1α(HIF-1α)是否参与去势后前列腺萎缩过程.方法24只SD大鼠分为3组,其中A组(n=8)为假手术对照组,B组(n=8)为去势组,C组(n=8)为雄激素替代组(去势后肌注十一酸睾酮50mg/kg);术后3天处死,通过半定量RT-PCR检测与HIF-1α在去势前后前列腺表达变化.结果去势后大鼠前列腺的体积萎缩变小;雄激素替代组出现前列腺增生变大;对照组正常的大鼠前列腺有HIF-1 α mRNA低水平表达,去势组HIF-1α mRNA表达量增加,雄激素替代组HIF-1αmRNA表达量减少,与正常对照组比较,去势组的HIF-1α mRNA的表达量显著增加(P＜0.05),雄激素替代组的HIF-1αmRNA的表达量显著减少(P＜0.01).结论前列腺组织的缺氧参与去势后大鼠前列腺的早期萎缩过程.     

SD大鼠肺中降钙素基因相关肽的分布及缺氧对其含量的影响

本研究用免疫细胞化学方法(ABC法)观察了降钙素基因相关肽(CGRP)在SD大鼠肺中的分布,缺氧对肺中神经内分泌细胞内CGRP含餐的影响。结果表明:含CGRP的神经纤维分布在肺血管平滑肌层中及其周围、气管-支气管树的粘膜下层;含CGRP的神经内分泌细胞位于气管一支气管树的上皮层、粘液腺中和肺实质内。缺氧不引起火鼠肺的神经内分泌细胞数目改变,但可使这些细胞内的CGRP含量增加。