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PubMedDate not supplied

Probability of survival based on ELISA titer following challenge of vaccinated chickens with the X-73 strain of Pasteurella multocida.

The probability of survival of chickens following a challenge dose of the X-73 strain of Pasteurella multocida was calculated based on enzyme-linked immunosorbent assay (ELISA) titer. Chickens were vaccinated subcutaneously with the Clemson University strain of P. multocida. On days 3, 5, 7, 10, 12, 14, 21, and 28 post-vaccination, 10 vaccinated chickens and 5 unvaccinated controls were selected at random, bled, and then challenged with 2000 colony-forming units of X-73. The ELISA titers to P. multocida vaccination and responses to challenge were recorded. A logistic procedure predicted probability of survival related to ELISA titer. The ELISA titer and survival were highly correlated. A flock profile for each day of challenge was developed based on a probability of survival (PS) at the following levels: PS less than 25%, 25% less than or equal to PS less than 50%, 50% less than or equal to PS less than 75%, and PS greater than or equal to 75%. The antibody response of the chickens through 28 days post-vaccination demonstrated a classic response to vaccination.

Animals↗

PubMed1985

The probability of exclusion of ancestries based on genetic observations.

One can extend exclusion of ancestry beyond paternity: for example, to grandparents or other types of ancestors. Naturally, the probability of successful exclusion is smaller for more remote ancestors. The case that we have especially considered is that of exclusion on the basis of grandparents, of which there have been recent applications. A method of calculating the average probability of exclusion, P, in such situations is developed and applied to different genetic systems including DNA polymorphisms available today. As usual, multiallelic genes like HLA are by far the most informative, but a substantial number of other genes should also be tested to reach a reasonable probability of exclusion. The effect of inbreeding on P is demonstrated to be negligible.

Alleles↗

PubMed1985

The probability of dying of injuries by the year 2000.

Life tables in which the probability of dying of injuries in the United States from 1985 to 1999 are determined may be useful for clinicians in counseling persons concerning the risk of fatal injuries. Overall, more than 1% of persons aged 10 to 34 years in 1985 probably will die of injuries by the year 2000. For white males aged 5 to 29 years in 1985, white females aged 5 to 19 years in 1985, and black males aged 5 to 24 years in 1985, over half of all the estimated deaths during the next 15 years will be probably due to injuries.

Actuarial Analysis↗

PubMed1978

Probability of paternity exclusion when relatives are involved.

In diagnosis of paternity by means of polymorphic markers, the proportion of men excluded on the basis of the phenotypes of the mother and child is the best index for controlling information. Its expected value, the probability of exclusion of a male chosen at random with respect to a random child-mother couple, calculated from gene frequencies of every genetic system, may be modified by a close relationship between the mother, the real father, and the presumptive father. The father and even more the brother of the mother, if he is the father of the child, diminishes the probability of exclusion of an individual chosen at random in the population, and if he is falsely accused, he has a higher probability of being excluded. On the other hand, the brother of the real father chosen at random in the population has the least chance of being excluded. The two different rules of exclusion are involved in the calculations, the first one being the more reliable.

Child↗

PubMed1980

The diagnosis of carcinoma in transurethral resectates of of the prostate. A study of the probability of overlooking malignant tissue when only part of the material is embedded for histological examination.

The purpose of this retrospective study based on the findings in routinely processed material from fifty-two consecutive cases of prostatic carcinomas is a mathematical calculation of the probability of including a carcinoma in the histological sections from tissue obtained by transurethral resection of the prostate when different embedding practices are followed. The analysis shows that if a material of a composition similar to ours were examined, the calculated probability to include at least one prostatic chip with malgnant tissue in the histological sections would be about 91% if one paraffin-block is made. The probability increases to about 96% when two blocks are used and comes close to 99% with four blocks.

Aged↗

PubMed1995

Probability revision.

This article examines the principles of probability revision and four different ways of obtaining post-test probabilities: the hypothetical cohort method, likelihood ratios and odds, the Nomogram, and precalculation. The authors then show where pre-test probabilities can be obtained, and then how to interpret multiple tests.

Coronary Disease↗

PubMed1995

Using data from epidemiologic studies to revise probabilities.

Information about the relationship between risk factors and the probability of disease is often reported by an odds ratio, although its use for revising the probability of disease in a clinical setting is not intuitive and requires complex computations. A somewhat better approach is Bayesian probability revision. The authors present a method where likelihood ratios can be obtained from odds ratios, and they present simple computational methods for implementing all of the techniques described.

Epidemiologic Methods↗

PubMed1995

New estimates of undocumented Mexican migration and the probability of apprehension.

Using a new source of data, we estimate the probability of apprehension among Mexican migrants attempting to cross into the United States without documents. Over the period 1965-1989 we found an average apprehension probability of .35, confirming earlier estimates. We then applied annual probabilities to estimate the gross volume of undocumented Mexican migration and adjusted these figures to derive estimates of the net undocumented inflow.

Adult↗

PubMed1994

A non-excluded set method for the calculation of paternity probability.

Forensic judgment of paternity depends on genetic and nongenetic evidence. Sometimes genetic marker tests can provide clear evidence to exclude a falsely accused man, but they do not always succeed. On the other hand, if the accusation is true, the alleged father will not ever be excluded by genetic marker tests. When a nonexclusion case occurs after one or more marker tests, a report of paternity probability is required in the court. The current methods for calculating the paternity probability are the "paternity index method" and the "nonexclusion method." A number of recent articles have openly debated the fallacies, validity and utility of both methods. This paper briefly reviews the two methods and proposes a non-excluded set method along with examples for illustrating the various patterns of paternity probabilities of the three methods.

Forensic Medicine↗

PubMed1994

Probability of gene identity by descent: computation and applications.

Two genes at a given locus are identical by descent (IBD) if both have been inherited from a common ancestor. We present an algorithm for computing the probabilities of all IBD relationships among the genes of pedigree members. We show how to use these probabilities to calculate the probability of any combination of genotypes or phenotypes for the pedigree members. Applications to linkage analysis and genetic counseling are illustrated with examples. The algorithm also can be used to calculate the generalized kinship coefficients proposed by others.

Algorithms↗

PubMed1993

Predicted probabilities of hospital death as a measure of admission severity of illness.

This paper evaluates a new method for assessing hospital admission severity of illness based on disease-specific models (logistic regression) of the probability of in-hospital mortality. Results for the 26 disease groups in MDC 4--Diseases of the Respiratory System, MDC 5--Diseases of the Circulatory System, and MDC 6--Diseases of the Digestive System are presented using data on all 1991 admissions from 111 hospitals throughout the United States. These disease models are empirically derived using clinical findings from laboratory, radiology, pathology, diagnostic procedures, patient history and physical exam, as well as patient age and sex. Each predictive algorithm is presented, and the strong predictive performance of these models is indicated by the average C statistic of .870. A predicted probability of death is calculated for each hospital patient in the study sample, and these probabilities comprise a continuous variable that indicates admission severity of illness.

Algorithms↗

PubMedDate not supplied

[A neuropharmacological analysis of individual preference for the probability and quality of reinforcement].

Under the influence of diazepam in doses of 0.2-2.0 mg/kg in a situation of different probability and value of a reinforcement the dogs--sanguinics and melancholics change their strategy of behavior, from the preference at norm of a reinforcement of the low probability but the better quality to that of the high probability but the worse quality. Under the same conditions the strategy of behaviour of cholerics and phlegmatics practically does not change. The change of behaviour strategy under the influence of diazepam in sanguinics and melancholics is proposed to be connected with a depressing effect of the drug on the hippocampus and amygdala and simultaneous activation of the hypothalamus and the frontal cortex. The data obtained are discussed from the position of P. V. Simonov's concept on the four above-mentioned brain macrostructures as the basis of the type of the higher nervous activity and behaviour of animals and man.

Amygdala↗

PubMed1993

Modulation of the mitochondrial cyclosporin A-sensitive permeability transition pore. I. Evidence for two separate Me2+ binding sites with opposing effects on the pore open probability.

This paper reports an investigation on the regulation of the mitochondrial cyclosporin A-sensitive permeability transition pore (MTP). Energized, coupled rat liver mitochondria incubated in sucrose medium in the presence of phosphate maintain a high proton electrochemical gradient (delta microH) and a low permeability to solutes. Addition of a small (10-20 microM) Ca2+ pulse leads to a transient membrane depolarization. After Ca2+ accumulation, a high delta microH is recovered, and mitochondria remain coupled indefinitely. Yet, addition of fully uncoupling concentrations of carbonyl cyanide-p-trifluoromethoxyphenyl hydrazone (FCCP) brings about MTP opening within seconds. This finding confirms that MTP opening is the consequence rather than the cause of membrane depolarization, and allowed us to study the operation of the MTP in a synchronized population of mitochondria, since pore opening can be triggered by the addition of uncoupler under a series of experimental conditions. We find that three regulatory sites can be defined: (i) an internal Me2+ binding site: when this site is occupied by Ca2+, the pore "open" probability increases, while other Me2+ ions (Sr2+, Mn2+) have an inhibitory effect; (ii) an external Me2+ binding site: when this site is occupied by Me2+ ions, including Ca2+, the pore open probability decreases; (iii) an independent cyclosporin A binding site: when this site is occupied by cyclosporin A the pore open probability decreases. We show that at variance from the case of cyclosporin A, MTP inhibition by the phospholipase A2 inhibitors nupercaine and trifluoperazine is Ca(2+)-competitive and is presumably related to interference by these drugs with Ca2+ binding to the internal regulatory site.

Animals↗

PubMed1993

Match probabilities in racially admixed populations.

The calculation of match probabilities is the most contentious issue dividing prosecution and defense experts in the forensic applications of DNA fingerprinting. In particular, defense experts question the applicability of the population genetic laws of Hardy-Weinberg and linkage equilibrium to racially admixed American populations. Linkage equilibrium justifies the product rule for computing match probabilities across loci. The present paper suggests a method of bounding match probabilities that depends on modeling gene descent from ancestral populations to contemporary populations under the assumptions of Hardy-Weinberg and linkage equilibrium only in the ancestral populations. Although these bounds are conservative from the defendant's perspective, they should be small enough in practice to satisfy prosecutors.

DNA Fingerprinting↗

PubMed1995

A probability database for decision-analytic models of coronary revascularization procedures.

The time required to extract probabilities from medical literature is a primary reason decision analysis is not used more frequently for individual patient management decisions. Objective clinical trial information from the medical literature for one management decision was placed in a database which provided probabilities when queried. The database was tested with decision-analytic models of specific patient cases from the medical literature. Performance was assessed in terms of the ability to select trials which resembled the patients' individual characteristics, the number of trials providing probabilities for a given outcome, and the number of follow-up points available for that outcome. The timely assistance the database provides in expediting literature review and synthesis could enable the more common use of decision analysis in management decisions for individual patients.

Adult↗

PubMed1996

Probability of malignancy in solitary pulmonary nodules using fluorine-18-FDG and PET.

UNLABELLED: Nearly one-third of solitary pulmonary nodules are radiographically indeterminate for the presence of malignancy. METHODS: FDG-PET imaging was used to differentiate benign and malignant solitary pulmonary nodules in 61 patients with radiographically indeterminate nodules. After confirmation of the histological diagnosis, the probability for cancer was established for positive and negative PET scans and compared to the risk estimates calculated using other patient variables. RESULTS: FDG-PET had a sensitivity, specificity and positive predictive value of 93%, 88% and 92%, respectively, for detecting malignancy in indeterminate solitary pulmonary nodules. The probability of malignancy with a positive PET scan is 83%, which increases with the patient's age (90% in >60 yr) and the size of the nodule. A negative PET scan is associated with only a 4.7% risk of malignancy. FDG-PET also accurately characterized hilar/mediastinal lymphadenopathy in 12 patients with associated lymph node lesions. CONCLUSION: FDG-PET imaging can be a useful noninvasive test to determine the risk estimate or probability of cancer as well as preoperative staging in patients with radiographically indeterminate solitary pulmonary nodules.

Adult↗

PubMed1996

[A method to calculate the probability of paternity between relatives--a paternity case where the putative father was a deceased granduncle].

To test paternity in a case where the putative father was a deceased uncle of mother (plaintiff's granduncle), we designed a new method to calculate the probability of paternity likelihood. The putative father's genotypes of red cell antigens, HLA and short tandem repeat (STR) polymorphism were estimated from those of mother and sister of the plaintiff. When the probability was calculated from the frequencies in the unrelated individuals (the standard method), a significant bias might be introduced since the putative father and the plaintiff were likely to have the same alleles come from their common ancestry. Therefore, we designed a new method to calculate the likelihood ratio from the frequencies in the group of mother's uncles estimated from mother's genotypes. The probability (0.9299) calculated with our method was found to be lower than that (0.9992) done with the standard method indicating that the new method could remove the bias introduced from the incest.

Adult↗

PubMed1996

Group sequential designs for monitoring survival probabilities.

In the present paper we derive the asymptotic joint distribution of the Nelson-Aalen estimators for the cumulative hazard function (or the Kaplan-Meier estimators for the survival function) calculated at different (possibly random) calendar time points of a survival study. This result is used to develop group sequential designs for clinical trials in which patients are enrolled over an extended period and the survival probability at a given failure time point is the parameter of primary interest. The proposed designs allow monitoring the survival probability (or probabilities) at interim looks so that the study can be terminated when there is sufficient evidence for a positive or negative result. A detailed illustration is provided with a problem from the National Wilms Tumor Study Group, which motivated this research.

Adolescent↗