0.5级电子式电能表的设计与实现

本文论述了一种普及型电子式电能表的设计原理和实现方法，具体讨论了时分割乘法器和电流互感器的组成和误差分析，最后给出测试结果。     

Retrograde blood circulation and ischemic heart disease

The author performed experiments on 350 dogs and X-ray postmortem studies of 1520 corpses of subjects who had died of various diseases and injuries. It was found that in occlusive great vessels in the ischemic organs and tissues, retrograde circulation developed, which completely maintained their viability under definite conditions. Retrograde venous blood flow to diseased organs and tissues drastically increased in insufficient retrograde arterial blood circulation. Under certain conditions, surplus venous blood influx caused edema and their dysfunctions. The mechanisms of retrograde circulation account for asymptomatic occlusion of the great vessels.     

光隔离器及其相关的磁光材料

本文简要介绍了磁光隔离器的理论、结构和分类 ,并提出了该器件今后发展的几个问题 ,最后介绍了几种磁光材料     

中国台湾电信市场现状

台湾电信市场的开放大致分四个阶段,从1995年起,陆续开放了移动通信、卫星通信及固定通信等多种业务。固网市场,2001年新世纪资通、台湾固网和力霸宽频电信的加入打破了中华电信的独家垄断,开始形成四强竞争的新局面。移动领域,1997年底6家运营商8张民营执照的发放开始了该领域史无前例的竞争。在2001年1月,台湾大哥大、远致电信、亚太行动宽频、联邦电信和中华电信获得了3G执照,累计竞标金额达488.99亿元(新台币)。     

A new family of yeast genes implicated in ergosterol synthesis is related to the human oxysterol binding protein

We have identified three yeast genes, KES1, HES1 and OSH1, whose products show homology to the human oxysterol binding protein (OSBP). Mutations in these genes resulted in pleiotropic sterol-related phenotypes. These include tryptophan-transport defects and nystatin resistance, shown by double and triple mutants. In addition, mutant combinations showed small but apparently cumulative reductions in membrane ergosterol levels. The three yeast genes are also functionally related as overexpression of HES1 or KES1 alleviated the tryptophan-transport defect in kes1Δ or osh1Δ mutants, respectively. Our study implicates this new yeast gene family in ergosterol synthesis and provides comparative evidence of a role for human OSBP in cholesterol synthesis.     

Ti-23Al-14Nb-3V合金氩弧焊接头的显微组织及其力学性能

研究了预热对Ｔｉ－２３Ａｌ－１４Ｎｂ－３Ｖ合金焊接性，特别是对消除氩弧焊冷裂纹的作用以及对接头显微组织和力学性能的影响。结果表明，焊前预热可有效降低该合金的冷裂倾向。经预热处理后，焊缝区的结晶层状线消失，热影响区的硬度峰得到缓和，整个焊缝的显微硬度分布趋于均匀，但焊缝区的枝晶发生粗化，热影响区有所扩大。焊件接头的拉伸试验表明，预热可使焊缝区的接头强度系数增加，但无论预热与否，接头强度均低于母材强度，且不显示宏观塑性。     

Nonsulfhydryl-reactive phenoxyacetic acids increase aqueous humor outflow facility

PURPOSE: The phenoxyacetic acid, ethacrynic acid (ECA), has potential use in glaucoma therapy because it acts to increase aqueous outflow in vivo and in vitro. In human trabecular meshwork (HTM) cell culture, ECA acts to change cell shape and attachment, effects that have been correlated with microtubule (MT) alterations and chemical sulfhydryl (SH) reactivity. To further explore these actions, we evaluated two non-SH reactive phenoxyacetic acids, inadcrinone and ticrynafen, and the MT-disrupting drug vinblastine. METHODS: Excised bovine and porcine eyes were perfused and outflow facility measured. Calf pulmonary artery endothelial and HTM cells were grown in culture and cytoskeletal effects evaluated after drug treatment. RESULTS: Indacrinone, ticrynafen, and vinblastine all caused an increase in outflow facility. In contrast with ECA, the outflow effects of indacrinone and ticrynafen were not blocked by excess cysteine. Although indacrinone and ticrynafen produced changes in cell shape in vitro, the beta-tubulin staining pattern of treated cells was not altered. Vinblastine caused cell shape change and the expected MT disruption. CONCLUSIONS: Phenoxyacetic acids can increase aqueous outflow facility and alter HTM cell shape and attachment in vitro by a non-SH, non-MT mechanism (which is probably shared also by ECA). These findings suggest the possibility of a broader class of glaucoma drugs that may be directed at the HTM. An understanding of the cellular target for these drugs has implications both for potential glaucoma therapy and for the cytoskeletal mechanisms involved in normal outflow function.