Myelination in chronically-alcoholic mice

Summary Chronically-administered ethanol, not impaired nutrition, exerts a specific effect to decrease myelination as measured by the activity of the marker enzyme for myelin, 2, 3-cyclic nucleotide 3-phosphohydrolase.Acknowledgment. This work was supported in part by N.I.H. Biomedical Research Support Grant Program, Grant No. 1-507-RR07155-01. To whom reprint requests should be addressed.     

Antifertilityeffects of clonidine in laying hens

Summary Clonidine was anovulatory and markedly antigonadal in laying hens when infused for 1 week from minipump implants at daily rates of 1.08 mg per hen or greater. The ovaries of hens treated with clonidine responded to FSH injections which suggests that the antigonadal effect of clonidine resulted from a reduction in the output of gonadotropin by the pituitary. These data suggest that ₂ receptors may be important in regulating avian fertility.     

高性能模数转换器ADS8411及其应用

ADS8411是一款2MSPS采样速率的16位逐次逼近(SAR)模数转换器(ADC).该器件再次显著提高了本身已属业界速度最快的16位SAR转换器产品系列的采样率,其主要面向要求高速、高精度的高级应用,例如医学成像、便携式医疗仪器、零等待数据采集系统、数字通信等.文中介绍了ADS8411的性能特点、内部结构及引脚排列,并给出了其和8位通用数据总线微控制器的接口原理图.     

新疆高等级公路沿线灾害性天气及其分布

为了预防灾害性天气对新疆高等级公路交通安全的影响，以新疆吐鲁番-乌鲁木齐-大黄山高等级公路和乌鲁木齐-奎屯高等级公路沿线自然环境的分析为前提，分析了灾害性天气在其公路沿线的时空分布。结果表明：降雨主要集中在夏季；降雪主要集中在当年的11月中旬至次年的3月中旬之间；雾天在冬、春两季较常见；大风、扬沙和沙尘暴主要出现于春夏两季。     

气垫上测定气体阻尼系数的一种方法

本文从能量的观点，给出了计算气体粘滞阻尼系数b值的另一种方法．     

Changes in erythrocyte membrane lipid composition affect the transient decrease in membrane order which accompanies insulin receptor down-regulation.

We have recently demonstrated, using electron paramagnetic resonance (EPR) spectroscopy, that insulin receptor internalization in response to insulin incubation (down-regulation) in human erythrocytes is accompanied by a transient decrease in membrane order, as measured by the 2T' parallel order parameter. Since membrane lipids play such an important role in receptor internalization, we investigated the possible effects that an alteration of the normally-occurring lipid profile might have on down-regulation and the concomitant transient decrease in membrane order. Consequently, human erythrocytes enriched with cholesterol and erythrocytes from cirrhotic patients were examined, because both of these groups of cells have a higher cholesterol/phospholipid molar ratio (CH/PL) than controls. The 5-nitroxystearate spin label, which inserts into the lipid bilayer of cell membranes, was used to monitor changes in 2T' parallel for a 3-h period at 37 degrees C. We report here that both cholesterol-enriched and cirrhotic erythrocytes do not down-regulate, as demonstrated by binding assays, and that they do not show the typical transient decrease in membrane order observed in controls. The results seem to indicate that a more ordered membrane inhibits internalization of the insulin receptor in erythrocytes, and that an increase in membrane disorder is necessary for insulin receptor down-regulation.     

材料热处理工程师职业资格教育与本科教育相结合的改革与实践

针对材料热处理工程师的基本素质要求,通过优化课程体系,强化实践性环节,营造工程环境,开展工程师职业资格培训,建设"双师型"师资队伍等措施,初步探讨了工程师职业资格教育与本科教育相结合的培养模式,取得了一定的成效.