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More than 600 cases of ovarian tumors were analyzed for histological type, age of patient, bilateral occurrence, mobility and malignant degeneration in restant ovaries. Tumors of germinal epithelial origin show the highest incidence (24%) of malignant degeneration, tumors of germ cells the lowest (3,5%). Incidence of malignant degeneration increases in relation to the age of the patient from 2% (and under 30 years) to 36,5% (60-70 years). Each form of tumor has its typical age peak, which is about 20 years higher for carcinomas than for their benign counterpart. Bilateral ovarian tumors are malignant in 29%, one-sided only in 13%. Among freely movable ovarian tumors, only 6% enclose a malignant tumor, among adhaerent ones 34%. The examination of the prognosis of granulosacell-tumors, dysgerminomas and teratoblastomas is based on a larger material.
Objective.Atrial fibrillation (AF) burden has become an increasingly important endpoint in long-duration rhythm monitoring, but reliable burden estimation requires more than accurate AF detection alone. In particular, when burden is derived by aggregating predicted AF probabilities over time, probability calibration may directly affect burden validity under external dataset shift.Approach.This study developed an interpretable-interval feature model for AF detection and evaluated it using record-wise cross-validation on a development cohort and independent cross-dataset external validation on public Holter electrocardiographic databases. Window-level performance was assessed using the area under the receiver operating characteristic curve (ROC-AUC), area under the precision-recall curve (PR-AUC), Brier score, expected calibration error (ECE), and calibration intercept and calibration slope. Recording-level AF burden was estimated using both probability-based and hard-label aggregation and evaluated using mean absolute error (MAE) and agreement analyses.Main results.The model showed high discrimination in both development and external evaluation, with external ROC-AUC ofand PR-AUC of. However, external calibration deteriorated despite preserved ranking performance, with Brier score of, ECE(15) of, calibration intercept of, and calibration slope of. In the external cohort, probability-based burden estimation preserved strong association with reference burden but showed weaker raw agreement than hard-label aggregation, with MAE ofversus, consistent with systematic probability underprediction. Repeated external recalibration across record-level splits substantially improved probability quality and probability-based burden estimation. Median probability-burden MAE decreased fromwithout recalibration toafter Platt recalibration andafter isotonic recalibration, while median ECE(15) decreased fromtoand, respectively.Significance.These findings indicate that-interval-based AF detection maintained strong ranking performance in the tested external cohort, but probability calibration should be evaluated explicitly when predicted probabilities are aggregated into AF-burden estimates.
The modified self-consistent phonon approximation is generalized to calculate the open base pair probability of a (TATA)2 insert between two semi-infinite poly(dA-dC) . poly(dG-dT) helices. An iterative method based entirely on the Green's function method is developed to compute the open interbase hydrogen bond probability of the insert and near bases versus temperature. The open interbase hydrogen bond probability is calculated for two temperatures and compared with perfect homopolymer open base pair probabilities at room temperature. The probability of opening is enhanced by a factor of two for the major groove bond of the AT pair at the transcriptional downstream end of the (TATA)2 insert. The total base pair opening probability of that pair is enhanced by 54%. The probability of the next inline GC base pair to be open is increased by a factor of ten.
The effects of postoperative subconjunctival 5-fluorouracil (5-FU) injections on the surgical outcome of trabeculectomy in the Japanese were studied in a total of 362 eyes of 263 glaucoma patients with the postoperative follow-up of 1-9 years. The probability of successful intraocular pressure (IOP) control at the 5-year point of the continuing follow-up was calculated by the life-table method of Kaplan-Meier. The eyes that had undergone trabeculectomy with postoperative injections of 5-FU (5-FU group) included 165 eyes with primary open-angle glaucoma (POAG), 38 eyes with secondary glaucoma (SG) and 60 eyes with refractory glaucoma. The eyes that had undergone trabeculectomy without postoperative 5-FU (control group) included 46 eyes with POAG, 31 eyes with SG and 22 eyes with refractory glaucoma. The surgical techniques and postoperative care were virtually identical between the two groups, except that the control group did not receive the postoperative 5-FU. The total amount of 5-FU given to each case averaged 36.5, 36.0 and 49.5 mg for POAG, SG and refractory glaucoma, respectively. At the 5-year follow-up point, the probability of maintaining IOP control below 21 mmHg with or without medication in the 5-FU group was 92.5% for POAG, 87.4% for SG and 57.5% for refractory glaucoma; while without medication the probability was 58.2, 54.8 and 27.8%, respectively. The probability of IOP control below 16 mmHg with or without medication in the 5-FU group was 77.9% for POAG, 66.8% for SG and 26.9% for refractory glaucoma; without medication the probability was 55.2, 49.8 and 24.5%, respectively. In the control group, the corresponding probability for each type of glaucoma was much lower than that in the 5-FU group, and the probability for IOP control below 16 mmHG was 0.12% at the 5-year follow-up point. In the 5-FU group, the mean postoperative IOP in successfully treated eyes remained at about 12 mmHg throughout the first 5 years of the follow-up period. There was no significant difference in incidence of postoperative complications between the 5-FU and control groups, except that corneal epithelial defect was noted in 38.8% of the eyes in the 5-FU group. No late complications related to the use of postoperative 5-FU were observed.(ABSTRACT TRUNCATED AT 400 WORDS)
The four major brain gangliosides, GM1, GD1a, GD1b, and GT1b, were determined in cerebrospinal fluid (CSF) of 43 patients with "probable Alzheimer's disease (AD)" and 40 healthy controls without psychiatric or neurological disorders. The total concentration of the four gangliosides did not differ significantly between "probable AD" group (116 +/- 58 nmol/L) and controls (92 +/- 31 nmol/L), but the proportion between the gangliosides was changed. In the "probable AD" group compared with the age-matched control group, there was an increase in both the GM1 (22.6 +/- 9.3% vs 12.6 +/- 4.1%; p < 0.0001) and GD1a (32.1 +/- 9.8% vs 23.3 +/- 5.7%; p < 0.0005) proportion, and a decrease in the GD1b (20.0 +/- 6.6% vs 23.8 +/- 6.0%; p < 0.05) and GT1b (25.3 +/- 7.9 vs 40.3 +/- 9.3%; p < 0.0001) proportion. The proportion of GM1 showed a positive correlation with age in the control group (r = 0.45; p < 0.01), but a negative correlation with age in the "probable AD" group (r = -0.37; p < 0.05). Thus, although the increase in proportion GM1 in the "probable AD" group was preferentially found in younger "probable AD" patients, it was not caused by age differences. While the pathogenetic mechanism for these changes in CSF-gangliosides in "probable AD" remains to be established, it may reflect the degeneration of nerve cells and synapses.
An expression is derived for the prior probability of linkage between a random trait locus and any one of m random marker loci, and this probability is computed form=1, 10, 20, 30, 50 and 100. A similar expression is derived for two trait loci, and computed for m=1, 10, 20 and 30. When one trait locus and 30 marker loci are being studied, a priori there is over a three-quarter probability that the trait locus should be syntenic with at least one of the markers, and about a one-half probability that there should be a linkage mappable from recombination frequencies. If two traits are studied, then the prior probability that at least one should be syntenic with one of the 30 markers is 0-94, and there is a three-quarter probability that such a linkage should be mappable.
Probability estimates of angiographic coronary artery disease made by experienced, board-certified staff cardiologists were compared with those of cardiologists in training (fellows). In addition, estimates made before coronary angiography were compared with those made several months later based on written clinical summaries of 15 items of objective clinical and test data. Cardiologists were asked to estimate the probabilities of coronary artery disease, multivessel disease, and triple-vessel or left main disease. The study population consisted of 510 consecutive patients without valvular disease referred for the first time for coronary angiography to three hospitals. Both staff and fellows consistently overestimated the pre-angiographic probability of coronary artery disease. The probabilities estimated from patient summaries were always significantly lower than the pre-angiographic assessments. Only staff cardiologists reliably assessed the probabilities of coronary artery disease during the second assessment (p less than 0.05). Thus, estimates of disease probability based on clinical judgment vary according to the source of information, and these estimates are more accurate when physicians have objective data on hand and do not know the identities of the patients.
A method has been developed, which we call the "response probability density function technique," which has applications in predicting the probability of injury in a wide range of biodynamic situations. The method, which was developed in connection with sonic boom damage prediction, utilized the probability density function of the excitation force and the probability density function of the sensitivity of the material being acted upon. The method is especially simple to use when both these probability density functions are lognormal. Studies thus far have shown that the stresses from sonic booms, as well as the strengths of glass and mortars, are distributed lognormally. Some biodynamic processes also have lognormal distributions and are, therefore, amenable to modeling by this technique. In particular, this paper discusses the application of the response probability density function technique to the analysis of the thoracic response to air blast and the prediction of skull fracture from head impact.
To investigate the relation between physicians' predicted probabilities of pneumonia and their utilities for ordering chest x-rays to detect pneumonia, the authors studied 52 physicians who ordered chest x-rays of 886 patients presenting to an emergency department with fever or respiratory complaints. Physicians estimated the probability of pneumonia prior to obtaining the results of the chest x-ray. Utilities were assessed by asking physicians to consider a hypothetical patient presenting with acute respiratory symptoms, with unknown chest x-ray status, and to rank on a scale from +50 ("best thing I could do") to -50 ("worst thing I could do") their rating scale utilities for not diagnosing pneumonia and not ordering a chest x-ray when the patient had pneumonia (i.e., missing a pneumonia), and for diagnosing pneumonia and ordering a chest x-ray when the patient did not have pneumonia (i.e., ordering an unnecessary x-ray). The utility for ordering an unnecessary x-ray was negatively correlated with average predicted probability (r = -0.1495, p = 0.29), whereas the utility for missing a pneumonia was positively correlated with average predicted probability (r = 0.2254, p = 0.11), although the correlations were not statistically significant. Relative chagrin, defined as the difference in these utilities, was significantly inversely correlated with average predicted probability (r = -0.2992, p less than 0.035), even after adjusting for the prevalence of pneumonia seen by each physician (partial r = -0.42, p less than 0.0027). It is concluded that physicians who experienced greater regret over missing a pneumonia than over ordering an unnecessary x-ray estimated lower probabilities of pneumonia for patients for whom they ordered x-rays.(ABSTRACT TRUNCATED AT 250 WORDS)
Cancer incidence in countries representative of three patterns of reproductive cancer and age-specific mortality was used to estimate the effect of oral contraceptive use on the lifetime probability of reproductive cancer under three sets of assumptions about the effects of oral contraceptives. Under the set of assumptions considered likely, oral contraceptives were estimated to reduce or increase only slightly the lifetime probability of any reproductive cancer in each setting. Under worst-case assumptions, oral contraceptives were estimated to increase the lifetime probability of reproductive cancer only modestly in settings with low cancer rates and in settings with high rates of breast, ovarian, and endometrial cancer, but it might have a large impact on lifetime probability of reproductive cancer in settings with high cervical cancer rates. Under best-case assumptions, oral contraceptives were estimated to decrease the lifetime probability of reproductive cancer in each setting; this reduction was estimated to be greatest in settings where endometrial and ovarian cancer incidence are high.
Five groups of 10 undergraduate subjects each participated in an experiment to examine the effects of perceived control over, and the probability of occurrence of, noxious (white-noise) stimulation on anticipatory heart rate (HR) deceleration. All groups performed an arithmetic task, the numbers for which were changed on each of the 20 trials, but three groups were defined as active groups since they were instructed that the occurrence of noxious stimulation was contingent upon their performance on the task. The actual probability of occurrence of noxious stimulation (i.e., either 0.9, 0.5 or 0.1) was manipulated between these three groups. A fourth (passive) group (0.5 probability of occurrence) was instructed as to the non-contingent relationship between performance and the aversive white noise. The last group was a control group which only performed the task, and thus both provided an estimate of the rate of return to baseline following the expected HR acceleration to the task and eliminated the need for a within-subject control period to assess HR deceleration. The results indicated that all active and passive groups produced significant HR decelerations, relative to the control group, prior to the noxious stimulus. However, all active groups (regardless of probability levels) displayed significantly greater, and required more trials to maximally develop, anticipatory deceleration than the passive group. In addition, the results for the active groups revealed a direct relationship between the probability of occurrence of noxious stimulation and the magnitude of anticipatory deceleration. It is argued that the results cannot be adequately accommodated by the preparatory-adaptive-response theory. A deployment-of-attention account is suggested since it appears both to account for the obtained pattern of results completely and to generate additional testable predictions for the future.
One-dimensional short-range interaction models for specific-sequence copolymers of amino acids have been developed in this series of papers. In this paper, a general method for predicting protein conformation (that is based on a one-dimensional short-range interaction model, and eliminates the need for the empirical rules introduced in papers III and IV) is described. The present method involves the use of conformational (or conformational-sequence) probabilities of higher order than the first- or second-order probabilities used in papers IV and V, i.e., it treats a sequence of any number of residues; it thus alters the predictive methods that involved empirical rules in papers III and IV, and low-order (first- or second-order) probabilities in papers IV and V. The general method is applied here to the prediction of the backbone conformations of proteins, using the three-state model [helical (h), extended (epilson), and other coil (c) states] proposed in the theoretical formulation of paper II. The statistical weights in the three-state model are evaluated from the atomic coordinates of the x-ray structures of 26 proteins. The conformational-sequence probabilities (taken for three consecutive residues for numerical computation in this paper) are calculated for all possible triads (i.e., for all possible combinations of the three states, h, epilson, and c for each residue) for bovine pancreatic trypsin inhibitor and clostridial flavodoxin, in order to select the most probable conformations of these proteins. The predicted results for these proteins are compared to those predicted in paper III and to those observed experimentally. The method is applied further to the prediction of the backbone structures of homologous neurotoxin proteins whose amino acid sequences are known but whose x-ray structures are not. The effects of variation in the amino acid sequence on the conformations of the backbones are discussed from the point of view of the homologies in the amino acid sequences of 19 neurotoxins. Application of the present general predictive method to a four- and a multistate model is also described.
Previously, we reported enhanced P3 amplitudes to between-category deviations among high and low probability events. Here, we tested the effects of a within-category difference. Subjects performed a go/no-go button press task as they viewed repeated, randomly-ordered presentations of nine double-digit numbers. Eight numbers fell within a prescribed range (42-49, standards); prior to testing, subjects selected one standard number for later recall. A ninth, out-of-range (91, deviant) number was also included. Subjects were tested under two conditions, in which they responded either to one (low response probability) or to seven (high response probability) standard nonselected numbers, designated as targets. Relatively larger P3s were consistently apparent only when the deviant nontarget was associated with a low probability response to a nontarget. There was a selective effect of nontarget response probability on P3 amplitude to the deviant nontarget. Our results indicate that within-category deviation detection is facilitated by "controlled" attention to the structure of the stimulus field.
The values of the mean relative probabilities of transversions and transitions have been refined on the basis of the data collected by Jukes and found to be equal to 0.34 and 0.66, respectively. Evolutionary factors increase the probability of transversions to 0.44. The relative probabilities of individual substitutions have been determined, and a detailed classification of the nonsense mutations has been given. Such mutations are especially probable in the UGG (Trp) codon. The highest probability of AG, GA transitions correlates with the lowest mean change in the hydrophobic nature of the amino acids coded.
In a series of six experiments deaf and hearing adolescents were compared on attainment of formal operations in Piaget's theory as represented by performance on probability problems. Performance of deaf subjects provided a desirable control comparison, since their knowledge of probability concepts was most likely acquired outside school classrooms. The probability problems were usually binary choice situations that required no verbalizations and were designed to illuminate strategies, as well as to indicate conceptual stage. Two experiments, one a long-term training study of over two years' duration, used supplementary preadolescent subject groups. Most of the hearing adolescents and many of the deaf adolescents attained the formal operatory level for probability concepts according to the criteria described by Piaget and Inheldermtheir criteria can be criticized, however, as insufficiently demanding, although they do point up the difficulty of defining the place of computational abilities in formal operationsmresults from several experiments suggested a second and higher level of formal operatory attainment around the ages of 14 to 15. Further theoretical insights were obtained regarding the implicit rules that frequently appeared to guide subjects' choices; a surprising variety of strategies were reported. Analysis of choice tendendies showed consistent avoidance of calculations and selection of the choice with the greatest absolute rather than relative frequency (or area) even when these strategies produced systematic errors. Subjects were generally unable to combine probability information from two different sources. In the long-term training experiment spontaneous improvement was shown by children at formal operatory ages even without training, but not by younger children. Deaf adolescents performed as well as hearing adolescents on easy problems, but they made more errors on several types of more difficult problems; Deaf adolescents were also less consistent than the hearing in use of rules, and in several experiments they showed a two- to three-year performance lag.
Algorithm for the computerized calculation of probability of paternity likelihood was investigated. The probability is calculated by Essen-Möller's formula as W = X/(X+Y) = 1/(1 + Y/X). The X value is also given as X = Hl, m, n/Kl, m, where kl, m and Hl, m, n are the probabilities of mother-child and mother-child-father combinations, respectively. In this study, four functions as F(PQ) = [1-(P not equal to Q)] x p x q, Z(RS) = (1- (R = S)), K(PQ,RS) = 1/2([(R = P) + (R = Q)].s + [(S = P) + (S = Q)].r).F (PQ)/Z(RS) and H(PQ, RS, TU) = 1/4([(R = P) + (R = Q)] [(S = T) + (S = U)] + [(S = P) + (S = Q)] [(R = T) + (R = U)]) x F(PQ).F(TU)/Z(RS) were created, where PQ, RS and TU were the genotypes of mother, child and the alleged father, P, Q, R, S, T and U were their alleles, and p, q, r, s, t and u were the allele frequencies. The equality or inequality in parenthesis was the relation operator which gave -1 or 0 when the expression was true of false, respectively. Then, three formulae as Y = n sigma k = l F([TU]k), Kl, m = 1 sigma i = l m sigma j = l K ([PQ]i, [RS]j) and Hl, m, n = l sigma i = l m sigma j = l n sigma k = l H([PQ]i, [RS]j, [TU]k) were obtained, where [PQ]i, [RS]j and [TU]k were one of the mother's, one of the child's and one of the putative father's genotypes considered from their phenotypes, respectively. Using these formulae, the probability of paternity likelihood could be calculated in every case. These formulae were programmed in BASIC language using a personal computer. Algorithm for the calculation of the probability in the deceased party was also investigated.
Suppose that we wish to know the probability that an object belongs to a class. For example, we may wish to estimate the probability that a patient has a particular disease, given a set of symptoms, or we may wish to know the probability that a novel peptide binds to a receptor, given the peptide's amino-acid composition. The conventional approach is to first use a classification algorithm to find partitions in feature space and to assign each partition to a class, and then to estimate the conditional probabilities as the proportion of patients or peptides that are correctly and incorrectly classified in each partition. Unfortunately, this estimation method often gives probability estimates that are in error by 20% or more, and thus can cause incorrect decisions. We have implemented and compared alternative methods. In Monte Carlo simulations the alternative methods are substantially more accurate than is the current method.