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Early Termination of Clinical Trials: Earlier than planned termination of clinical trials.Clinical Trials Data Monitoring Committees: Committees established to review interim data and efficacy outcomes in clinical trials. The findings of these committees are used in deciding whether a trial should be continued as designed, changed, or terminated. Government regulations regarding federally-funded research involving human subjects (the "Common Rule") require (45 CFR 46.111) that research ethics committees reviewing large-scale clinical trials monitor the data collected using a mechanism such as a data monitoring committee. FDA regulations (21 CFR 50.24) require that such committees be established to monitor studies conducted in emergency settings.Frameshift Mutation: A type of mutation in which a number of NUCLEOTIDES deleted from or inserted into a protein coding sequence is not divisible by three, thereby causing an alteration in the READING FRAMES of the entire coding sequence downstream of the mutation. These mutations may be induced by certain types of MUTAGENS or may occur spontaneously.Clinical Trials as Topic: Works about pre-planned studies of the safety, efficacy, or optimum dosage schedule (if appropriate) of one or more diagnostic, therapeutic, or prophylactic drugs, devices, or techniques selected according to predetermined criteria of eligibility and observed for predefined evidence of favorable and unfavorable effects. This concept includes clinical trials conducted both in the U.S. and in other countries.Double-Blind Method: A method of studying a drug or procedure in which both the subjects and investigators are kept unaware of who is actually getting which specific treatment.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Peptide Chain Termination, Translational: A process of GENETIC TRANSLATION whereby the terminal amino acid is added to a lengthening polypeptide. This termination process is signaled from the MESSENGER RNA, by one of three termination codons (CODON, TERMINATOR) that immediately follows the last amino acid-specifying CODON.Terminator Regions, Genetic: DNA sequences recognized as signals to end GENETIC TRANSCRIPTION.Peptide Termination Factors: Proteins that are involved in the peptide chain termination reaction (PEPTIDE CHAIN TERMINATION, TRANSLATIONAL) on RIBOSOMES. They include codon-specific class-I release factors, which recognize stop signals (TERMINATOR CODON) in the MESSENGER RNA; and codon-nonspecific class-II release factors.Clinical Trials, Phase III as Topic: Works about comparative studies to verify the effectiveness of diagnostic, therapeutic, or prophylactic drugs, devices, or techniques determined in phase II studies. During these trials, patients are monitored closely by physicians to identify any adverse reactions from long-term use. These studies are performed on groups of patients large enough to identify clinically significant responses and usually last about three years. This concept includes phase III studies conducted in both the U.S. and in other countries.Transcription Termination, Genetic: The discontinuation of transcription at the end of a transcription unit, including the recognition of termination sites and release of the newly synthesized RNA molecule.Clinical Trials, Phase II as Topic: Works about studies that are usually controlled to assess the effectiveness and dosage (if appropriate) of diagnostic, therapeutic, or prophylactic drugs, devices, or techniques. These studies are performed on several hundred volunteers, including a limited number of patients with the target disease or disorder, and last about two years. This concept includes phase II studies conducted in both the U.S. and in other countries.Clinical Trials, Phase I as Topic: Works about studies performed to evaluate the safety of diagnostic, therapeutic, or prophylactic drugs, devices, or techniques in healthy subjects and to determine the safe dosage range (if appropriate). These tests also are used to determine pharmacologic and pharmacokinetic properties (toxicity, metabolism, absorption, elimination, and preferred route of administration). They involve a small number of persons and usually last about 1 year. This concept includes phase I studies conducted both in the U.S. and in other countries.Research Design: A plan for collecting and utilizing data so that desired information can be obtained with sufficient precision or so that an hypothesis can be tested properly.Codon, Terminator: Any codon that signals the termination of genetic translation (TRANSLATION, GENETIC). PEPTIDE TERMINATION FACTORS bind to the stop codon and trigger the hydrolysis of the aminoacyl bond connecting the completed polypeptide to the tRNA. Terminator codons do not specify amino acids.Rho Factor: A protein which effects termination of RNA synthesis during the genetic transcription process by dissociating the ternary transcription complex RNA;-RNA POLYMERASE DNA at the termination of a gene.Controlled Clinical Trials as Topic: Works about clinical trials involving one or more test treatments, at least one control treatment, specified outcome measures for evaluating the studied intervention, and a bias-free method for assigning patients to the test treatment. The treatment may be drugs, devices, or procedures studied for diagnostic, therapeutic, or prophylactic effectiveness. Control measures include placebos, active medicines, no-treatment, dosage forms and regimens, historical comparisons, etc. When randomization using mathematical techniques, such as the use of a random numbers table, is employed to assign patients to test or control treatments, the trials are characterized as RANDOMIZED CONTROLLED TRIALS AS TOPIC.