220-Dictionary of Pharmaceutical Medicine, 2nd Edition-Gerhard Nahler Annette Mollet-3211898352-S

78gamgamma error syn. type III error; statistical risk of declaring a treatmentbetter when in fact it is worse (truth: A > B, false judgment: A< B); usually negligible (for a = b = 0.05, then g < 1/10,000,000).Gantt chart syn. bar chart; named after Henry L. Gantt who developeda graphic charting system to depict activities across a timescale;the chart displays each task as a bar, which shows the task’sstart and finish dates and duration on a time scale; → see projectmanagement.Gaussian curve → see distribution, standard deviation.Gehan’s design Useful for rejecting a drug (or hypotheses) from furtherstudy; usually there is no control group and the design can bekept unblinded when treatment results are objective resp. obvious;example: if with an antitumor drug no response occurs among thefirst 14 subjects, then the hypotheses of a response rate ≥ 20% canbe rejected, accepting a false error rate of 5%; g.d. controls theprobability of a false negative result by calculating the probabilitythat the first n patients do not respond to the treatment for a prespecifiedrate of response p to the drug; the initial sample size isdetermined as the smallest value of n such that the probability ofn consecutive failures is less than some given error rate β; similardesigns are: ECOG d., one sample multiple testing d.gene A segment of chromosome that encodes the necessary regulatoryand sequence information to direct the synthesis of a proteinor RNA product; (e.g. Operator; Regulatory g.; Structural g.; Suppressorg; G. are instructions (made of “base pairs” of nucleotides)that give organisms their characteristics; these instructions arestored in each cell of organisms in a long, string-like molecule, theDNA; within cells, the DNA is wound-up on themselves appearingas finite structures called chromosomes; each organism has hischaracteristic number of chromosomes, for humans the number is46 (23 pairs); → see also genome, proteomics.gene expression The process through which a gene is activated at particulartime and place so that its functional product is produced.gene mapping Determination of the relative locations of genes on achromosome.gene sequencing Determination of the sequence of nucleotide basesin a strand of DNA.gene therapy syn. genomics therapy; the replacement of a defectivegene in an organism suffering from a genetic disease; more general:techniques inducing immunological reactions by the transferof new genetic material into human cells for the purpose of treating,preventing or diagnosing a disease; recombinant DNA techniquesare used to isolate the functioning gene and insert it intocells (e.g. by delivering genes via an artificially altered virus such as