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B Djulbegovic

Publications and source records attributed to B Djulbegovic.

47 records · Page 3Linked to original sources
PubMed1991

A new algorithm for the diagnosis of polycythemia.

A new algorithm for the diagnostic evaluation of erythrocytosis is presented. This algorithm is based on principles of decision-making analysis and on the pathophysiology of erythrocytosis. The initial task is to identify smokers, because of the high probability that they have "smoker's" polycythemia. The current diagnostic criteria for polycythemia vera may be insufficient when the probability of disease is low but may be too rigorous when the probability of disease is high.

Algorithms↗
PubMed1990

Comparison of sex steroid receptor determinations in human breast cancer by enzyme immunoassay and radioligand binding.

Most investigators comparing ligand-binding procedures for quantifying estrogen and progestin receptors in human breast cancer with procedures employing monoclonal antibody-based methods have utilized an inappropriate variety of reaction conditions, including the elimination of sodium molybdate in the steroid-binding assays. We studied 197 biopsies of human breast cancer, comparing the results of simultaneous measurements of both estrogen and progestin receptors in identical cytosols by enzyme immunoassay and by radioligand binding using the commercially available kits developed by Abbott Laboratories and by DuPont/NEN Products, respectively. Regression analyses comparing the results from the two procedures indicated a linear relationship, with correlation coefficients ranging from 0.79 to 0.93 for both types of receptors over a wide range of data. Using the widely established cutoff value of 10 fmol/mg of cytosol protein for the ligand-binding method, and calculating sensitivity and specificity limits according to McNeil et al. (1975), an equivalent cutoff value of 15 fmol/mg of cytosol protein was determined for the enzyme immunoassay of these receptors. Endocrine status of the patient did not appear to alter the cutoff values of either estrogen or progestin receptors when determined by enzyme immunoassay. We recommend that these cutoff values be considered until the results of clinical correlations are completed.

Breast Neoplasms↗
PubMed1989

Influence of O.C.T. embedding compound on determinations of estrogen and progestin receptors in breast cancer.

Estrogen receptor (ER) and progestin receptor (PR) concentrations in tumor biopsies are important predictive indicators of a clinical response to endocrine therapy of breast cancer. To assess interference of O.C.T. (optimum cutting temperature) embedding compound in assays of ER and PR by radioligand binding, we determined specific binding capacities and affinities of ER and PR in cytosols by a multipoint titration method, using split samples of 14 breast-tumor biopsies, one portion serving as untreated control, the other treated with O.C.T. There was no statistically significant difference between these two groups. We then compared these data with those of historical controls analyzed both in the presence and absence of sodium molybdate (10 mmol/L). Eighty breast-tumor specimens (mean +/- SD patients' ages, 59 +/- 14 y) embedded in O.C.T. compound and analyzed without molybdate gave ER and PR values that differed insignificantly from those for 306 samples (patients' ages, 61 +/- 14 y) untreated with O.C.T. Thirty-nine specimens (patients' ages, 58 +/- 15 y) embedded in O.C.T. compound were analyzed in the presence of molybdate and compared with the results for 288 specimens (patients' ages, 61 +/- 14 y) untreated with O.C.T. Again, there was an insignificant difference in the concentrations and affinities of receptors in the two groups. Evidently O.C.T. compound does not alter the receptor status of tumor biopsies.

Aged↗
PubMedDate not supplied

Comparison of different treatment strategies for diffuse large-cell lymphomas: a decision analysis.

There are more than 20 drug combinations in use for the treatment of diffuse large-cell non-Hodgkin's lymphoma (NHL). New treatments have been developed without prior comparison in clinical trials. The authors devised a Markov-process model to compare the efficacy of a first-generation combination chemotherapy regimen (CHOP) with that of a third-generation regimen (MACOP-B) using currently available data. For a typical 57-year-old male patient, life expectancy with MACOP-B was 12.1 years, compared with 8.3 years with CHOP. The remission rate after initial treatment and the functional status after the first remission is achieved were the most important determinants of life expectancy. It was still possible for CHOP to become better strategy provided that the initial remission rate with MACOP-B were lower than 50% or that functional status after remission was achieved were less than 66%. The analysis suggests that the most effective therapeutic regimen for diffuse large-cell lymphoma must not only result in a high remission rate but also cause minimal late sequelae. These two parameters were incorporated into the nomogram, which can serve as a basis for comparison of the efficacy of any chemotherapeutic regimen in non-Hodgkin's lymphoma.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Calculating confidence intervals for threshold and post-test probabilities.

We describe a method and a computer program, written in JavaScript, for calculating confidence intervals. The method uses Taylor's series to approximate the standard errors of a post-test probability and threshold probabilities and, from them, to obtain the associated confidence intervals. This method is valid if the variables of interest are stochastically independent.

Adult↗