大鼠纹状体边缘区神经元中乙酰胆碱激活的离子通道特性

用细胞贴附式膜片钳技术研究了急性分离的新生SD大鼠纹状体边缘区神经元中乙酰胆碱激活的离子通道的特性。发现通道有25PS和60PS两种电导状态,25PS通道为主要类型,因此,本文主要报道25PS通道的特性。ACh激活的单通道电流为快速内向电流,随着超极化程度增加而增加,反转电位约为0mV。通道开放具单个开放和簇状开放,其开放时间均可权指数拟和,单个开放时间常数为0．29ms和1.84ms,簇状开放时间常数为1．96ms和18.24ms。平均关闭时间也可双指数拟和,两个时间常数为1．70ms和54．00ms。通道开放概率为0．012,未表现出电压依赖性。提示纹状体边缘区神经元上存在乙酸胆碱受体离子通道。根据特性证实为烟碱型离子通道。     

Decreased incidence of arterial thrombosis using heparin-bonded intraaortic balloons

BACKGROUND: This experimental study sought to determine whether heparin-bonding of intraaortic balloons (IAB) would decrease the incidence of arterial thrombosis in the absence of systemic heparinization. METHODS: In 25 adult pigs, a 9F, 40-mL IAB was inserted into the femoral artery and positioned just below the takeoff of the left subclavian artery for 9 hours. Five animals received systemic heparin, 10 animals had no heparin, and another 10 animals received no heparin but the IAB was heparin-bonded (Duraflo II). Thrombus formation was assessed using a numerical scoring system (0 = no thrombosis to 3 = thrombus >5 cm or evidence of luminal compromise). RESULTS: Animals receiving heparin and heparin-bonded IAB had no thrombus formation around the IAB (mean +/- SE; 0 +/- 0.00 heparin versus 1.55 +/- 0.29 no heparin versus 0 +/- 0.00 heparin-bonded; p < 0.005), at the insertion site (0 +/- 0.00 heparin versus 1.55 +/- 0.29 no heparin versus 0 +/- 0.0 heparin-bonded; p < 0.005), and in the distal femoral artery (0 +/- 0.00 heparin versus 2.00 +/- 0.23 no heparin versus 0 +/- 0.00 heparin-bonded; p < 0.005). CONCLUSIONS: Heparin-bonding of the IAB significantly decreases thrombus formation in the absence of systemic heparinization.     

Favorable impact of stents after emergent coronary artery bypass for failed angioplasty

BACKGROUND: This study was undertaken to determine the impact of the use and availability of coronary stents on outcomes in patients requiring emergent coronary artery bypass graft (CABG) surgery following a failed percutaneous transluminal coronary angioplasty (PTCA). METHODS: Patients were divided into two groups based on the year of their CABG for a failed PTCA and the availability of stents: group 1, 1992 to 1994, stents not available (n = 34); and group 2, 1995 to 1997, stents available (n = 26). RESULTS: CABG patients in the group where stents were not available were more likely to have had an abrupt coronary occlusion (26 of 34 versus 3 of 26; p < 0.0001) and less likely to have had a dissection (8 of 34 versus 23 of 26; p < 0.0001) as their indication for emergent CABG. Patients in the stent era had a lower incidence of perioperative myocardial infarction (5 of 26 versus 17 of 34; p < 0.01) and a decreased mortality rate (0 of 26 versus 6 of 34; p < 0.03). In the 9 patients where stents were employed, patency of the lumen was restored in 8 patients and there was only 1 myocardial infarction. CONCLUSIONS: Stents have had a favorable impact on patients requiring an emergent CABG following a failed PTCA.     

中药复方对卧床模拟失重引起"血淤"的对抗效果

目的观察中药对卧床模拟失重引起血淤证改善的效果。方法１０名被试者随机分为中药组和对照组。两组均头低位－６°卧床７ｄ,中药组卧床中服中药复方,对照组服安慰剂。结果中药组的血淤证较对照组有明显减轻,某些生理指标维持卧床前状态,即血压平稳;心功能（每搏量、心肌收缩力、每搏功指数等）、尿量,与卧床前比较基本保持不变,而对照组比中药组血淤证较重。结论提示中医药可能成为防治短期航天失重时对机体影响的的一种选择措施     

噪声、振动复合因素对汉语语音清晰度影响的研究

目的 探讨噪声、振动复事因素下生成语音在听觉效果上的变化及变化规律。方法 在安静及信噪比分别为０ｄＢ和－６ｄＢ三种状态下进行清晰度测试,以研究噪声、振动复合因素组、单独噪声组、单独振动组及对照组４个组的语音材料清晰度变化规律。结果 和对照组相比,复合因素作用下语音清晰度有明显降低,检验结果非常显著;和单因素相比,多数情况下有显著性变化。研究还发现,清晰度的降低随听音环境的信噪比的降低而变得严重,当     

Regulation of the angiotensin type-1 receptor by antisense oligonucleotides occurs through an RNase H-type mechanism

Multiple, diverse sites in the coding region of the angiotensin type-1 receptor mRNA were targeted with 2'-deoxyribonucleotide antisense oligonucleotides (ONs). The uptake of 1 microM concentration of these ONs into Chinese hamster ovary cells was facilitated by the use of cationic liposomes. The antisense sequences reduced binding of 125I-angiotensin II by 57-73%, while mismatch ONs and reverse sequence ONs produced little reduction in receptor binding. These reductions in AT1 receptor binding were accompanied by comparable decreases in AT1 receptor mRNA levels. Furthermore, mRNA cleavage fragments corresponding in size to 3'-cleavage fragments were observed with two of the antisense ONs, consistent with the involvement of an RNase H-type enzyme. When 2'-methoxyribonucleotide analogs of these same sequences were tested, AT1 receptor mRNA levels were unchanged even though small reductions in AngII binding were observed. Antisense effects seen with these 2'-methoxyribonucleotide sequences may have arisen through a translational arrest mechanism. Direct comparisons between 2'-deoxyribonucleotide analogs and their 2'-methoxyribonucleotide counterparts show that antisense effects are significantly larger when they are mediated through an RNase H-type mechanism. 2'-methoxyribonucleotide sequences were most effective when they were directed against the translation initiation codon.     

电解铝厂职工恶性肿瘤死亡状况回顾性队列研究

对某电解铝厂职工恶性肿瘤死亡情况进行了１０年回顾性队列研究,以宁夏１９９０￣１９９２年人口年龄死亡专率为参比,计算了观察队列标化死亡比（ＳＭＲ）、癌症比例死亡比（ＰＭＲ和ＰＣＭＲ）,观察组肺癌超出量尤为显著,ＳＭＲ为１９０（Ｐ〈０．０１）,ＰＣＭＲ为１７１（Ｐ〈０．０５）。     

病人图书馆是医院图书服务的新领域

建立病人图书馆,以“图书治疗”、“图书护理”为患者提供服务,是现代医学模式转变的需要。国外病人图书馆的发展对病人治疗康复已起到了积极的作用。我国应根据国情建立不同模式的病人图书馆,为患者提供多种多样的服务。     

合肥郊区0—6岁儿童营养状况分析

目的：了解合肥郊区儿童的营养状况,评价农村儿保工作的质量。方法：于1990－1995年按既定诊断标准逐年调查全区0－6岁儿童佝偻病、缺铁性贫血（IDA）及营养不良的患病情况。结果;全区儿童营养不良、佝楼病及IDA的患病率分别为0.25％－1.06％,5.72％－18.44％及8．33％－42.9％;1992－1995年营养不良患病率有逐年下降的趋势,而佝偻病及贫血则相反;婴幼儿较学龄前儿童佝偻病患病情况严重,而贫血则相反;男女童营养状况无差异;经济状况较好的近郊儿童的营养状况明显好于经济状况较差的远郊儿童。结论：农村儿保工作的重点仍应放在营养缺乏病的防治上．对婴幼儿重点在佝偻病,学龄前儿童重点在IDA。     

Protection from oxidant injury by sodium-dependent GSH uptake in retinal Müller cells.

Glutathione (GSH) is known to play an important role in regulating oxidative damage to cells. The present study was initiated to examine the effect of exogenous GSH on oxidative injury in a retinal Müller cell line and to characterize GSH transport in these cells. Rat Müller cells (rMC-1) were incubated with varying concentrations of t-butylhydroperoxide (t-BHP) to induce oxidative stress, and cell viability was measured after addition of GSH. In other studies, kinetics of GSH uptake and Na+-dependency were examined by incubating cells with35S-GSH in Na+-containing and Na+-free buffers. GSH uptake was studied with GSH at concentrations varying from 0. 05-10 m m in NaCl buffer. In the presence of sodium, extracellular GSH provided protection against t-BHP-induced oxidant injury to rMC-1 cells; in contrast, the amino acid precursors of GSH did not have any effect on cell viability. GSH was taken up by rMC-1 cells in a concentration- and sodium-dependent manner. Kinetic studies revealed both a high affinity (Km approximately 0.31 m m) and low affinity Km( approximately 4.2 m m) component. Furthermore, GSH depletion had no significant effect on the rate of GSH uptake. The results show that physiological concentrations of GSH can protect Müller cells from oxidative injury. Both Na+-dependent and Na+-independent transport systems for GSH exist in Müller cells, and the Na+-dependent GSH transporter may be involved in the protective role of GSH.