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Results for “Repeatability and Reproducibility”

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At least 1,621 records · Page 90Linked to original sources

PubMed1996

[Reproducibility of measurement of intraocular lens location in situ with an anterior eye segment analysis system].

The reproducibility of the measurement (accuracy of repeated measurement) of intraocular lens (IOL) location in situ was studied using an anterior eye segment analysis system (NIDEK EAS-1000). The measurements were performed as follows: (1) errors at photography: 1) errors by the individual photographer 2) errors among three photographers. (2) errors at analysis: 1) errors by individual analysists 2) errors among six analysists. The greatest standard deviation was the accuracy of repeated measurement. Accuracy of repeated measurement (tilt and decentration) was (1) 1) 1.104 degrees, 0.083 mm, (1) 2) 0.866 degrees, 0.072 mm, (2) 1) 0.597 degrees, 0.079 mm, (2) 2) 0.562 degrees, 0.079 mm. From the data obtained in this study, the reproducibility of the EAS-1000 was satisfactory for measurement of IOL location.

Anterior Eye Segment↗

PubMed1996

Repeated transfer of small RNA virus populations leading to balanced fitness with infrequent stochastic drift.

The population dynamics of RNA viruses have an important influence on fitness variation and, in consequence, on the adaptative potential and virulence of this ubiquitous group of pathogens. Earlier work with vesicular stomatitis virus showed that large population transfers were reproducibly associated with fitness increases, whereas repeated transfers from plaque to plaque (genetic bottlenecks) lead to losses in fitness. We demonstrate here that repeated five-plaque to five-plaque passage series yield long-term fitness stability, except for occasional stochastic fitness jumps. Repeated five-plaque passages regularly alternating with two consecutive large population transmissions did not cause fitness losses, but did limit the size of fitness gains that would otherwise have occurred. These results underscore the profound effects of bottleneck transmissions in virus evolution.

Animals↗

PubMed1984

[Programmed stimulation in patients with malignant ventricular arrhythmia. II: Individual optimization of anti-arrhythmia therapy].

The major purpose of programmed ventricular stimulation in patients with malignant ventricular arrhythmias (sustained ventricular tachycardia/ventricular fibrillation) is not the diagnostic or prognostic evaluation but the individual optimization of antiarrhythmic therapy. For successful antiarrhythmic treatment, the choice of an adequate parameter of efficacy is of outstanding relevance: in patients with frequent daily episodes of malignant ventricular arrhythmias, proper treatment can be based on Holter monitoring; however, in patients with infrequent but life-threatening attacks, Holter monitory appears to be inadequate and programmed stimulation is the method of choice for proper treatment decisions. A total of 394 serial pharmaco-electrophysiological studies was performed in 82 patients with inducible sustained ventricular tachycardia or ventricular fibrillation. During the acute serial studies, one drug was tested each subsequent day using short-term intravenous infusions. The only criterion for drug efficacy was prevention of inducible sustained ventricular tachycardia or ventricular fibrillation that had been reproducibly initiated under control conditions before antiarrhythmic treatment. At least one preventive drug was found in approximately 2/3rd of the patients. Following serial acute studies using intravenous administration, an effective agent was selected and given orally. Programmed stimulation was repeated usually after three days demonstrating reproducibility of preventive efficacy in 90% of the trials. During a subsequent follow-up period of an average of 15 months, the number of acute events (9%) including sudden death or life-threatening recurrences of malignant ventricular arrhythmias was significantly reduced as compared to patients with non-optimized therapy (54%; p less than 0.05). The number of cardiac deaths due to progressive heart failures was not significantly different in patients placed on optimized or non-optimized antiarrhythmic treatment.

Administration, Oral↗

PubMed2000

Surnames and the Y chromosome.

A randomly ascertained sample of males with the surname "Sykes" was typed with four Y-chromosome microsatellites. Almost half the sample shared the same Y-chromosome haplotype, which has not been observed in control samples either from the same geographic region or from the United Kingdom as a whole. This points to a single surname founder for extant Sykes males, even though written sources had predicted multiple origins. The distribution of other Sykes Y-chromosome haplotypes were not significantly different from those in controls and may be accounted for by the historical accumulation of nonpaternity during the past 700 years, in which case the average rate estimate is 1.3%/generation. If this pattern is reproduced with other surnames, it may have important forensic and genealogical applications.

Fathers↗

PubMed2001

Estimating the percentage of Papanicolaou smears that can be reproducibly identified: modeling Papanicolaou smear interpretation based on multiple blinded rescreenings.

BACKGROUND: Multiple blinded rescreenings of Papanicolaou (Pap) smears for litigation purposes is based on the assumption that a subset of Pap smears can be reproducibly identified. The size of this subset is not known. METHODS: To estimate the size of the subset of Pap smears that can be reproducibly identified, a model was constructed based on the results of repeated blinded screenings in the AutoPap Primary Screening System Trial. Additional analysis came from data in the literature. RESULTS: Routine and AutoPap-assisted screening both have a detection rate for all detected abnormal cases of < 50%. Models with only two subsets or types of slides each with a different detection rate correlated well with the available data. Data from multiple rapid reviews strongly supported the existence of additional definable subsets. Although the percentage of cases with an expected detection rate of 100% in a three-subset model might have been as high as 30% of the abnormal cases detected in a single review, all estimates that included a second subset of slides with at least a 50% detection rate limited the percentage of slides in the 100% sensitive subset of slides to < 2% of all abnormal slides and < 6% of all abnormal slides detected by a single screening. CONCLUSIONS: Repeated screenings of Pap smears allowed more accurate models of the sensitivity of Pap-smear screening and the overall incidence of abnormal cases. The data strongly supported the existence of multiple subsets of Pap smears, which can be defined by repeated blinded rescreenings. The percentage of slides that can be reproducibly identified was small.

Data Interpretation, Statistical↗

PubMed1990

Capillary blood cell velocity in finger nailfold: characteristics and reproducibility of the local cold response.

The characteristics and reproducibility of nailfold capillary blood cell velocity (CBV) of the local cold response was evaluated in 30 cases by video-microscopy using a flying-spot technique. CBV, as well as flow stop duration during cooling, from a first and second test was significantly (P less than 0.05) reproducible, whether or not the test was repeated after 60 min or after an interval of 12 weeks. Because of interindividual variations in rest CBV, and a better reproducibility of the flow stop duration, this last parameter is more useful in clinical practice for follow-up evaluations of the local cold response test. The usefulness of the flying-spot generator for rapid and accurate measurement of CBV in finger nailfold capillaries is demonstrated in normal subjects and patients with primary Raynaud syndrome during a local cooling test.

Adult↗

PubMed2000

The concentration of hydrogen peroxide in exhaled air depends on expiratory flow rate.

Hydrogen peroxide (H2O2) is known to be detectable in exhaled air. The present study aimed to determine whether the concentration of exhaled H2O2 depends on expiratory flow rate in order to make inferences on the site of its production within the lung. Breath condensate was collected in cooled Teflon tubes, at three different expiratorv flow rates, in 15 healthy or mild asthmatic subjects. Tests were repeated 2-5 times to assess reproducibility. Mean+/-SEM concentrations of H2O2 at flow rates of 140, 69 and 48 mL.s(-1) were 0.12+/-0.02, 0.19+/-0.02 and 0.32+/-0.03 microM, respectively. These values differed significantly from each other (p<0.001). For comparison, average coefficients of variability within repeated measurements at each of the three flow rates were 68, 62 and 82%, respectively. These data demonstrate that the concentration of exhaled hydrogen peroxide depends on expiratory flow rate. Since flow dependence is an indicator of production within the airways, this result suggests that, to a large extent, the exhaled hydrogen peroxide originates within the airways. However, even under strictly controlled conditions, a high degree of variability persists, which may limit the usefulness of exhaled hydrogen peroxide as a marker of airway inflammation.

Adult↗

PubMed2002

Evaluation of methods for MR imaging of human right ventricular heart volumes and mass.

PURPOSE: To assess the utility of two different imaging directions in the evaluation of human right ventricular (RV) heart volumes and mass with MR imaging; to compare breath-hold vs. non-breath-hold imaging in volume analysis; and to compare turbo inversion recovery imaging (TIR) with gradient echo imaging in RV mass measurement. MATERIAL AND METHODS: We examined 12 healthy volunteers (age 27-59 years). Breath-hold gradient echo MR imaging was performed in two imaging planes: 1) perpendicular to the RV inflow tract (RVIT view), and 2) in the transaxial view (TA view). The imaging was repeated in the TA view while the subjects were breathing freely. To analyze RV mass using TIR images, the RV was again imaged at end-diastole using the two views. The RV end-diastolic cavity (RVEDV) and muscle volume as well as end-systolic cavity volume (RVESV) were determined with the method of discs. All measurements were done blindly twice to assess repeatability of image analysis. To assess reproducibility of the measurements, 6 of the subjects were imaged twice at an interval of 5-9 weeks. RESULTS: RVEDV averaged 133.2 ml, RVESV 61.5 ml and the RVmass 46.2 g in the RVIT view and 119.9 ml, 56.9 ml and 38.3 g in the TA view, respectively. The volumes obtained with breath-holding were slightly but not significantly smaller than the volumes obtained during normal breathing. There were no marked differences in the RV muscle mass obtained with gradient echo imaging compared to TIR imaging in either views. Repeatability of volume analysis was better in TA than RVIT view: the mean differences were 0.7 +/- 4.0 ml and - 5.4 +/- 14.0 ml in end-diastole and 1.6 +/- 3.1 ml and - 1.5 +/- 13.9 ml in end-systole, respectively. Repeatability of mass analysis was good in both TIR and cine images in the RVIT view but slightly better in TIR images: - 0.5 +/ -2.4 g compared to 0.8 +/- 2.9 g in cine images. Reproducibility of imaging was good, mean differences for RVEDV and RVESV were -1.0 +/- 4.8 ml and -0.8 +/- 2.8 ml, respectively. Mean difference for RVmass was -0.9 +/- 2.6 g. CONCLUSION: The present study suggests that gradient echo MR imaging is well applicable to RV volume and mass measurements. The best imaging plane for volumetric analysis seems to be the TA plane and there was no significant difference between breath-hold and conventional imaging. To assess RV mass, we recommend RVIT view; the TIR sequence quickly produced images of better quality compared to gradient echo images but no significant difference between masses was found and repeatability of analysis was equally good with both methods.

Adult↗

PubMed2003

Cross-sectional characteristics of the masseter muscle: an ultrasonographic study.

Cross-sections of the masseter muscle may now be measured non-invasively using ultrasonography. The purpose of the present study was to determine (1) whether the scanning level may affect cross-sectional measurements and (2) whether measurements made at identical levels may be reproducible. The study included 42 asymptomatic volunteers. Unilateral ultrasonographic investigation was performed with a linear (B-scan) 7.5 Mhz small-part transducer to register cross-sections of the masseter muscle on five different levels. Scans were made on the relaxed and contracted muscle. Measurements were made in two sessions with a time interval of at least 5 min. Statistical analysis consisted of univariate analysis of variance for repeated measurements. Data were analysed for reproducibility by using the method error and measurement error. For the ultrsonographic measurements the main effects of the variables 'session' (P=0.0001), 'level' (P=0.0001), and 'condition' (P=0.0001) were significant. Analysis of simple session-within-level effects revealed a significant difference between the repeated measurements for the most upper level (P=0.022), the upper level (P=0.012), and the most lower level (P=0.0001) of the relaxed muscle. An additional significant effect was found for the most lower level of the contracted muscle (P=0.015). Cross-sections evaluated at the middle (method error=0.31 mm; measurement error=2.0%) and lower level (method error=0.32 mm; measurement error=2.4%) of the contracted muscle were the most reproducible. The conclusion is that ultrasonography is a reproducible method for measuring cross-sections at the middle and lower level of the contracted masseter muscle.

Adolescent↗

PubMed1990

Reproducibility of growth hormone testing procedures: a comparison between 24-hour integrated concentration and pharmacological stimulation.

The purpose of this study was to compare the reproducibility of two approaches to the evaluation of GH secretion: the integrated concentration of GH (IC-GH), a physiological test of GH secretion, and pharmacological stimulation tests. IC-GH was determined in 40 poorly growing children twice within 4 weeks. The first and second IC-GH were highly correlated r = 0.859, P less than 0.001. One hundred and thirteen poorly growing children underwent pharmacological GH stimulation tests twice within 6 weeks. A moderate correlation was found between the first and second pharmacological test r = 0.524, P less than 0.01. Among the three pharmacological stimuli studied, clonidine (n = 81) had the highest reproducibility followed by arginine (n = 20), and insulin (n = 12). We conclude that IC-GH is more consistently reproducible than the GH response to repeated pharmacological stimulation.

Adolescent↗

PubMed2004

Reproducibility and reliability of the anatomic axis of the lower extremity.

Two observers measured the tibiofemoral angle of 60 knees on hip-knee-ankle and anteroposterior (AP) knee radiographs and repeated the measurements 6 months later. Intraobserver reproducibility was moderate. Interobserver reliability was poor. These findings were the same irrespective of which radiograph was used during the measurement. Hence, although an AP knee radiograph was as reliable and reproducible as the hip-knee-ankle view, the radiographic tibiofemoral angle should not be considered a precise measurement.

Bone Malalignment↗

PubMed1999

Transcranial Doppler sonography guided by magnetic resonance angiography for improved monitoring of intracranial arteries.

Transcranial Doppler (TCD) sonography combines the advantages of real-time hemodynamic information, cost-effectiveness, and bedside application. However, measurements can be difficult to reproduce because the spatial resolution and the determination of insonation angles are limited. The purpose of this study was to use the high anatomic resolution of three-dimensional (3D) magnetic resonance angiography (MRA) images for the stereotactic guidance of TCD in order to improve the accuracy and reproducibility of TCD examinations. The MRA examinations were performed on a 1.5 T scanner using a 3D flow compensated gradient-echo sequence. A noninvasive stereotactic mask was used for image registration. The MRA data were then transferred to a personal computer. An infrared tracking system registered the position of the head and the ultrasound probe during TCD. This enabled the authors to superimpose a virtual ultrasound beam onto the MRA projections of the intracranial arteries displayed on the monitor of the personal computer. This allows the examiner to easily identify the insonated intracranial artery and displays the insonation angle. In volunteer examinations (n = 10), the accuracy and reproducibility for the localization of specific vessel segments was 2.48 mm for the middle cerebral artery and 2.81 mm for all insonated intracranial arteries (middle cerebral artery, anterior cerebral artery, internal carotid artery, and posterior cerebral artery). Without navigation the reproducibility of vessel segment insonation dropped to 4.7 mm for the middle cerebral artery and to 4.84 mm for all vessels. The authors conclude that 3D MRA, acquired as an initial procedure in patients with intracranial vascular disorders, can be used to provide stereotactic guidance for repeated TCD examinations. This facilitates the reproducible insonation of specific vessel segments.

Adult↗

PubMed2000

A comparative study of two methods of quantifying the soft tissue profile.

One of the most important components of orthodontic diagnosis is the evaluation of the patient's soft tissue profile. There have been many attempts to quantify the soft tissue profile based on the lateral cephalogram. Yet, the methodology used to evaluate the profile varies widely among studies, and there has been no consistency in the way straight lines are constructed in the analysis of the soft tissue contours. The purpose of the current study was to compare the values obtained by 2 drawing methods (tangent line and anatomic points) of constructing angles, and to assess the intraobserver and interobserver reproducibility for both methods. There were statistically significant differences between the 2 methods for 9 of the 10 measurements evaluated. In the comparison of reproducibility assessed by Pearson correlation analysis, both methods showed statistically significant correlations between repeated measurements. The anatomic point method, however, showed greater reproducibility by means of a paired t-test. In the analysis of intraobserver reproducibility, 2 measurements showed significant differences with the anatomic point method and 4 measurements demonstrated significant differences when the tangent line method was used. In the analysis of interobserver reproducibility, 5 measurements showed significant differences in the anatomic point method, while 6 measurements represented significant differences in the tangent line method. Our results indicate that a precise description of the methodology used in the analysis of the soft tissue must be provided because of the differences between methods. In the analysis of soft tissue contours, the construction of lines with the anatomic point method is more reproducible than the tangent line method.

Adolescent↗

PubMed1975

[A comparison of the results of 4 national methods for the evaluation of disinfectants in 2 laboratories (author's transl)].

At present the testing and assessment of disinfectants is carried out according to different methods in different countries. The result of this is that certain preparations or concentrations are allowed for use in some countries while they are not in neighbouring countries. A study was carried out jointly at two universities with the object of testing the reproducibility of these methods and standardizing them. Furthermore, an attempt was to be made to arrive at common test methods. In 2 labortories (A,B) we tested and compared the disinfectant activity of three disinfectant standards (phenol, aldehyde, iodophor) against Staphylococcus aureus and Pseudomonas aeruginosa (1) in the suspension test according to the "Richtlinien für die Prüfung chemischer Desinfektionsmittel" (Directions governing the testing of chemical disinfectants) of the DGHM, (2) in the suspension test of the "Dutch Commission for Phytopharmacy," (3) according to the "Use-Dilution Method" of the A.O.A.C. and (4) in the capacity test according to KELSEY and SYKES. Every individual test was repeated ten times. In addition we determined the reproducibility of the results by repeating the tests several times with one and the same culture and with different cultures (on different days). The exact method is described elsewhere (7). The statistical evaluation of the mean values (Tables 1,3,5 and 7) and variances (Tables 2,4,6 and 8) leads to the following findings: The results obtained with the various methods depend on the lab. technique and were specific to the germs and preparations tested. The reproducibility was best in the DGHM suspension test and the capacity test according to KELSEY and SYKES; the mean values of the two laboratories were closest for the Dutch test of the Commission of Phytopharmacy. The greatest mean value differences and scatter were observed with the A.O.A.C. "Use-Dilution Method." The conclusion of this investigation is that for the preliminary testing of disinfectants a method should be recommended which enables the determination of the acturl germ count reduction after varying periods of action and with well-defined organic challenge. In order to assess the disinfectant action, however, such a test - which answers most of our questions and has optimum reproducibility - must be supplemented by main tests which simulate practical conditions as near as possible.

Aldehydes↗

PubMed1976

Transactions of an international conference. Worldwide concern: better dental care for more people. An international collaborative study. How oral surveys were conducted.

A special form and field manuals defining examination criteria were prepared for recording the following: 1. Number of teeth present both primary and permanent 2. Periodontal disease (a) Oral hygiene using the simplified oral hygiene index. (b) Periodontal condition using a modified P.I. index. (c) Periodontal treatment requirements. 3. Dental caries The DMF index was used with separate coding for filled or crowned teeth having additional primary or secondary decay. 4. Dento facial anomalies Both treatment need and treatment status were recorded. 5. Prosthetic status Possession and requirements for partial or full dentures and bridges were recorded for the age groups 13-14 and 35-44. 6. Oral pathology Pathological conditions of the gingiva and oral mucosa. 7. Need for immediate attention Conditions causing or likely to cause pain or danger to general health unless immediate treatment was given. The recording was carried out using fibre optic illumination, disposable mirrors and sickle probes. X-rays were not utilized. Two roving epidemiologists first established reproducible criteria and then calibrated the local examiners. Re-calibration took place at intervals and repeat examinations of a small sample population ensured reproducibility of recordings. The completed charts were sent to the WHO Oral Health Unit where they were edited and the data transferred to computer tape for analysis. For the present reports three variables--number of carious teeth, caries treatment/need ratio and number of teeth with gingivitis were selected for special study.

Adolescent↗

PubMed2000

Hepatic MR imaging with a dynamic contrast-enhanced isotropic volumetric interpolated breath-hold examination: feasibility, reproducibility, and technical quality.

PURPOSE: To evaluate the feasibility, reproducibility, and technical quality of a dynamic contrast material-enhanced isotropic three-dimensional (3D) volumetric interpolated breath-hold hepatic magnetic resonance (MR) imaging examination. MATERIALS AND METHODS: Fifty patients underwent 3D spoiled gradient-echo imaging (4.2/1.8 [repetition time msec/echo time msec]; flip angle, 12 degrees; interpolation in three directions; intermittent fat saturation; pixel size </= 2.5 mm in all dimensions) before and dynamically after administration of gadopentetate dimeglumine, with the first enhanced acquisition timed for hepatic arterial dominance by using a test bolus of contrast material. Qualitative and quantitative measures of image quality were determined. Patterns of arterial and venous anatomy were assessed. Ten patients (20%) underwent repeat imaging within 6 months, and reproducibility was evaluated. RESULTS: Hepatic contrast-to-noise ratios for nonenhanced and arterial, portal venous, and equilibrium phase studies averaged 13.0 +/- 12.6 (SD), 17.4 +/- 11.8, 30.4 +/- 16.2, and 28.6 +/- 21.1, respectively. During arterial phase, the liver enhanced a mean of 29% of the maximal enhancement as measured during portal venous phase. Hepatic vascular anatomic variants were comparable in distribution to those cited in published articles. Repeat studies were not significantly different in image quality when compared with original studies. CONCLUSION: High-quality arterial phase 3D volumetric interpolated breath-hold images can be obtained reliably and reproducibly when timed by using a test dose of contrast material.

Adipose Tissue↗

PubMed2001

Bedside monitoring of cerebral blood flow by transcranial thermo-dye-dilution technique in patients suffering from severe traumatic brain injury or subarachnoid hemorrhage.

Bedside measurement of cerebral blood flow (CBF) represents an important feature in monitoring of neurointensive care patients which is hard to establish. Therefore, we adopted a recently described thermo-dye-dilution-based approach for monitoring CBF in patients suffering from severe cerebral insults, that is, traumatic brain injury (TBI) or subarachnoid hemorrhage (SAH). Combined fiberoptic-thermistor catheters were placed in one jugular venous bulb and in the abdominal aorta of 16 patients. Following central venous injection of a 50-mL bolus of precooled indocyanine green (ICG) solution, CBF was determined as a function of the mean transit times of coldness and dye. In addition, measurements of CBF using stable xenon-enhanced computerized tomography (sXe-CT) were simultaneously performed in 10 patients. A total of 272 thermo-dye-dilution measurements yielded 196 valid results, with CBF ranging from 26.2 to 144.8 mL 100 g(-1) min(-1). Reproducibility was fairly good, with the standard deviation within sets of repeated measurements being 6.3 mL 100 g(-1) min(-1) and 9.4 as the mean coefficient of variation. Simultaneously obtained values with sXe-CT displayed a good correlation (r = 0.843, p < 0.01); however, the thermo-dye-dilution method consistently overestimated CBF. Data analysis using the Bland and Altman methodology revealed a large bias of 45.7 mL 100 g(-1) min(-1) with a +/- 2 SD range of 37 mL 100 g(-1) min(-1), indicating a rather poor agreement. The thermo-dye-dilution method proved a reasonably reproducible technique, enabling repeated long-term bedside measurements of CBF in neurointensive care patients with a minimum of time effort. However, a high failure rate was also noted, and consistent overestimation of perfusion was observed in comparison to sXe-CT measurements. Although the thermo-dye-dilution technique has been successfully validated in patients with normal neurovascular function, its applicability for bedside monitoring of CBF appears uncertain in patients suffering from severe TBI or SAH.

Adolescent↗

PubMed1999

Regional reproducibility of microsatellite instability in sporadic colorectal cancer.

The reproducibility of microsatellite instability from different regions of the same sporadic colon cancer has not been addressed. We therefore microdissected and extracted DNA from three to nine separate regions of 13 highly unstable sporadic colon cancers. Each region was then evaluated by polymerase chain reaction amplification of 17 microsatellites: 10 tetranucleotide repeats, 2 noncoding mononucleotide repeats (BAT-26 and BAT-40), and 5 coding mononucleotide repeats (TGFBRII, BAX, MSH3, MSH6, IGFIIR). Microsatellite instability showed 100% regional reproducibility with respect to either the panel of 10 tetranucleotide repeats or BAT-26, and nearly 100% reproducibility with BAT-40, although regional variation in the percent instability and the size of unstable alleles was present. TGFBRII was more frequently mutated than any other coding mononucleotide repeat; frame shifts in this gene were identified in nearly every region of every tumor. Each of the five coding repeats showed regional variability in at least one tumor, and 10 of the 13 tumors showed variability with at least one coding repeat. This variability took the form of different mutant alleles (TGFBRII, BAX, MSH3) or mutations present in some but not all regions of a tumor (MSH6, IGFIIR, BAX, MSH3). We conclude that the regional reproducibility of generalized microsatellite instability as measured by noncoding repeats indicates that sampling is not a problem in these highly unstable tumors, and that the mismatch repair deficiency phenotype is acquired in the very late adenoma stage or early cancer stage of sporadic colonic tumorigenesis. The high frequency of TGFBRII mutations is consistent with acquisition of these mutations at a similar stage of tumorigenesis. The regional variability with respect to the presence or absence of a mutation in the other four coding mononucleotide repeats could lead to sampling error and is consistent with a somewhat later time of acquisition of these mutations. Genes Chromosomes Cancer 26:106-114, 1999.

Adult↗