OSEK/VDX——汽车电子系统的开放式平台

介绍了当前在国际汽车工业界日益占据主导地位的汽车电子系统开放式平台--OSEK/VDX体系.详细地论述了这种体系的由来、运行机制和最新的发展动向,以及它对汽车电子技术发展的深远影响.     

Prospective, randomized trial comparing blood and oxygenated crystalloid cardioplegia in reoperative coronary artery bypass grafting

OBJECTIVES: Reoperative coronary artery bypass grafting presents unique challenges for myocardial preservation. The purpose of this study was to compare oxygenated blood cardioplegia with oxygenated crystalloid cardioplegia during reoperative coronary artery bypass grafting using transesophageal echocardiography to assess regional wall motion of the left ventricle before and after cardiopulmonary bypass. METHODS: Sixty-one patients undergoing reoperative coronary artery bypass grafting were prospectively randomized to receive oxygenated blood cardioplegia or oxygenated crystalloid cardioplegia delivered with a combined antegrade-retrograde technique. Transgastric short axis views of the left ventricle were made with transesophageal echocardiography during the operation before cardiopulmonary bypass and immediately after cardiopulmonary bypass. Regional wall motion was graded by a blinded observer, and before cardiopulmonary bypass scores were compared with after cardiopulmonary bypass scores. RESULTS: No significant differences were found in the change in regional wall motion score from before cardiopulmonary bypass to after cardiopulmonary bypass between the blood and crystalloid cardioplegia groups. CONCLUSIONS: This study found blood and crystalloid cardioplegia to be equally efficacious for myocardial preservation during reoperative coronary artery bypass grafting.     

Laparoscopic cholecystectomy in pancreas transplant recipients

Laparoscopic cholecystectomy is the treatment of choice for symptomatic cholelithiasis. Since its introduction in 1987, this procedure has been employed with increasing frequency as its safety has been documented in numerous studies. Absolute contraindications to laparoscopic cholecystectomy have become relative contraindications, and patients previously felt to be at excessive risk for laparoscopic cholecystectomy are viewed as patients who may benefit from laparoscopic cholecystectomy. The use of this procedure in patients with comorbid medical conditions has the potential to decrease patient morbidity. Patients who have previously undergone solid organ transplantation and require immunosuppressive therapy are a group of patients who may benefit from laparoscopic cholecystectomy. We report four patients who have previously undergone combined renal and pancreas transplantation who underwent successful laparoscopic cholecystectomy.     

挣值理论在工程项目投资控制中的运用

挣值分析法是工程项目费用/进度综合度量和监控的有效方法.本文结合世界知名的专业项目管理软件P3E/C来论述挣值理论应用于项目投资控制的总体思路和操作方法.     

HfOxNy的场发射特性

用直流溅射和高温退火相结合的方法制备了HfOxNy薄膜并测试了其场发射性能,发现其具有较低的开启电场、较大的发射电流密度以及很好的发射稳定性.高压"锻炼"对提高HfOxNy场发射性能起着关键作用,这与高压"锻炼"下薄膜内部结构和表面性质的改变有关.对场发射机理的研究表明,HfOxNy的场发射符合经典的FN隧穿理论.     

Efficient 3-d capacitance extraction considering lossy substrate with multilayered green's function

An efficient algorithm for extraction of three-dimensional (3-D) capacitance on multilayered and lossy substrates is presented. The new algorithm presents a major improvement over the quasi-3-D approach used in a Green's function-based solver and takes into consideration the sidewalls of 3-D conductors. To improve the efficiency of the computation and the transformation of the Green's function, a nonuniform grid is adopted. The most computationally intensive part in the transformation of the Green's function is computed separately as technology-independent matrices Tk foremost. Once computed, Tk can be stored and used for any technology, thus the storage requirement and computational complexity are reduced from O (S/sup 2/) and O (S/sup 2/ log S/sup 2/), respectively, to just O [(log S/sub max/)/sup 2/]. Extensive tests have been performed to verify the new algorithm, and its accuracy has been established by comparing with other programs.     

锌钾硼对甜菜产质量效应及最佳施肥措施的研究

本文利用最优回归设计“310”方案,研究了黑土地甜菜 Zn、K_2O、B的效果及合理施用问题。得出甜菜块根产量、含糖、产糖量、灰分 K 和有害 N 与 ZnK_2O、B 肥回归关系显著的回归模型,分析了 Zn、K_2O、B 对上述五个指标的效应,明确了 Zn 是影响各项指标的主要因子,并采用频率筛选法,提出了兼顾上述五项指标的优质高产施肥措施。     

辐射对血液流变效应的研究及动物全身照射后全血粘度的变化规律

本文结果表明经一次大剂量全身照射后的机体血液流变的主要特性为全血表观粘度先高粘后低粘的双向性变化,从照后第一天起即升高。随着放射病病程的发展,在早期有一个高粘峰,其峰均值比照前升高47.80％。但因不同动物、不同剂量、不同均速,不同血源而变化不同。     

Drafting a parenteral nutrition order form utilizing a physician assessment process

The utilization of a physician critique process in the design of a parenteral nutrition order form, encouraging a standard order option, is assessed. In the critique process, physicians from surgery, medicine, and medical intensive care teams were tasked to use the draft order form and guideline sheet to prescribe a parenteral nutrition order for a hypothetical patient. Prescriber recommendations and problems with the nutrition order form and guideline sheet directed editorial improvements. The physician assessment process is an effective means to measure utility of a draft parenteral order form and prescribing guideline sheet. By utilizing physician expertise, deficiencies inherent in such an order form may be corrected prior to implementation.