VISUAL SEARCH AND FILM READER ERROR IN RADIOLOGY

放射学中的视觉搜索和读片器错误

• 批准号: 3170740
• 负责人: HAROLD L. KUNDEL
• 金额: $ 19.42万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1980
• 资助国家: 美国
• 起止时间: 1980-08-01 至 1992-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3170740
• 关键词: clinical biomedical equipment; computer assisted medical decision making; decision making; eye movements; image enhancement; image processing; mathematical model; noninvasive diagnosis; radiodiagnosis; radiology; vision

The long-term goal of these studies is the elucidation of the molecular mechanisms which underlie chromosome behavior and transmission. Specifically, the experiments are focused on two aspects of chromosome biology in the fruit fly Drosophila melanogaster, namely rDNA magnification and meiotic chromosome segregation. In each case the approach is based on : 1) the isolation of mutations and relevant chromosomal aberrations necessary for genetic dissection; 2) genetic and, where possible, molecular analysis of chromosome behavior; 3) the physical isolation of genes defined by these mutations; and 4) molecular analysis of the structure and expression of these genes. The term rDNA magnification denotes at least two phenomena which result in heritable and stable increases in X chromosomal rDNA redundancy within the germline of rDNA deficient males. We propsoe a series of genetic and molecular experiments aimed at: 1) elucidating the molecular mechanisms of magnification events; 2) identifying the genes or gene systems which carry out these events; and 3) determining the mechanisms by which the cell senses an rDNA deficiency and induces or allows the magnification response. These studies will provide valuable information regarding the mechanism by which cells can stably maintain or alter the redundancy of tandemly repeated genes and some insight into the mechanisms by which the rDNA is expressed and regulated. The second series of experiments centers on a genetic and molecular analysis of the distributive pairing system. This system ensures the regular segregation of nonexchange chromosomes during meiosis I in Drosophila females. Although a few mutants specifically defective in the process have been previously isolated, a much more extensive screen for mutations affecting distributive pairing is proposed. While the purpose of this mutant hunt is to obtain additional alleles of existing loci, it is also hoped that new loci will be identified. Experiments are also proposed to clone at least three genes specifically involved in distributive pairing. The immediate objective of these studies is a molecular analysis of a family of genes which function specifically during meiosis to facilitate chromosome segregation. Over a longer term these experiments will provide the necessary tools to identify the proteins encoded by these genes and determine their cellular and/or chromosomal location. This information will be essential for a molecular understanding of chromosome segregation.

这些研究的长期目标是阐明 构成染色体行为和染色体的分子机制 变速箱。具体地说，实验集中在两个方面 果蝇的染色体生物学研究进展 黑胃动物，即rDNA扩增和减数分裂 染色体分离。在每种情况下，该方法都基于： 1)突变和相关染色体的分离 基因解剖所需的异常；2)遗传和， 如有可能，对染色体行为进行分子分析；3) 物理隔离由这些突变定义的基因；以及4) 对这些基因的结构和表达的分子分析。 术语rDNA放大至少表示两种现象 导致X染色体可遗传和稳定的增加 RDNA缺陷男性生殖系内的rDNA冗余。 我们提出了一系列基因和分子实验，目的是 AT：1)阐明放大的分子机制 事件；2)识别执行 这些事件；以及3)确定 细胞感觉到rDNA缺乏，并诱导或允许 放大响应。这些研究将提供有价值的 关于细胞稳定的机制的信息 维持或改变重复基因的冗余度 对rDNA表达机制的一些见解 并受到监管。 第二系列实验的中心是一种基因和 分配配对系统的分子分析。这个系统 确保非交换染色体的规则分离 在雌性果蝇减数分裂I期。尽管有几个突变体 特别是在这个过程中有缺陷的人之前 隔离，更广泛地筛查影响 提出了分布配对的概念。虽然这个突变体的目的是 Hunt是为了获得现有基因座的额外等位基因，也希望 这个新的基因座将被识别出来。还建议进行实验，以 克隆至少三个与分布相关的基因 配对。这些研究的直接目标是一种分子 对一组基因家族的分析，这些基因具有特定的功能 减数分裂以促进染色体分离。超过一个更长的时间 这些实验将提供必要的工具来 确定这些基因编码的蛋白质并确定它们的 细胞和/或染色体定位。这一信息将是 对染色体的分子理解是必不可少的 种族隔离。