Search PubMed⌕ Search

Biomedical subjects

I Ben-Dov

Publications and source records attributed to I Ben-Dov.

42 records · Page 3Linked to original sources
PubMed1982

Refractory period after exercise-induced asthma unexplained by respiratory heat loss.

Fifteen asthmatic children and young adults each exercised for 6 min by cycling on a cycle ergometer while breathing either cold (4.1 degrees C +/- 0.5 SEM) and dry (2.05 mg/L +/- 0.05) air or warm (37.2 degrees C +/- 0.3) fully saturated air. Each subject performed 4 tests arranged in pairs. Test pair A consisted of cold dry exercise followed by another cold dry exercise and test pair B consisted of a warm humid exercise followed by a cold dry exercise. Ventilation, heart rate, and gas exchange were closely matched in all 4 tests in each subject with a mean oxygen consumption of 34.8 +/- 0.8 ml/min/kg. In test pair A, all subjects were rendered refractory by the first cold dry exercise as manifested by a significant attenuation of their exercise-induced asthma (EIA) after the second cold dry test (per cent decrease in FEV1, delta FEV1 = 16 +/- 4 compared with 38 +/- 4). In 3 subjects, the warm humid exercise did not cause EIA and did not render them refractory to the second cold dry exercise. The 12 remaining subjects exhibited a refractory period similar to that shown in test pair A. They did not develop EIA after the warm humid test (delta FEV1 = 1 +/- 2), but after the subsequent cold dry exercise the per cent decrease in FEV1 was 19 +/- 3, similar to that in the second of the 2 cold dry exercise tests. These experiments suggest that in the majority of subjects exercise per se appears to be the cause for refractoriness and not airway cooling or bronchoconstriction.

Adolescent↗
PubMed1980

Acute rheumatic fever in adults over the age of 45 years: an analysis of 23 patients together with a review of the literature.

The natural history of acute rheumatic fever (ARF) in adults has been studied from an analysis of 23 patients together with a review of a further 466 published cases. In contrast to the picture in juvenile ARF, in our patients (average age 55 yr), only arthritis (83%) and carditis (35%) were major criteria for the diagnosis. All patients had at least 3 minor criteria. To summarize, 39% of the patients, average age 56 yr were seen in their initial attack of ARF. In those patients with a previous history of rheumatic fever, the mean interval between the index attack and the first illness was 20.5 yr. Contact with young children appeared to be an important predisposing factor. None had an ESR of less than 50 mm in the first hour, even in the presence of cardiac failure. Findings in the acute illness included anemia (70%), hyperglobulinemia (70%), urinary sediment (66%), and hypercalcemia in 7 out of 12 cases. The response to treatment was good and only 1 patient of 13 followed-up developed a new valvular lesion. A survey of the literature shows that attacks of ARF may occur at any age; death in the acute episode is rare and occurs only in patients with severe preexisting valvular disease with congestive failure. The problem of diagnosing active carditis in the presence of rheumatic heart disease (RHD) is discussed. While juvenile ARF may be overdiagnosed, the diagnosis may be missed in the adult rheumatic patient whose cardiac state inexplicably deteriorates. In such patients evidence for a preceding streptococcal infection should be sought. Patients with a high risk of developing ARF include those with carditis in previous attacks, with preexistent RHD, and with several children in the family. These factors should be considered when advising on the duration of antibiotic prophylaxis.

Acute Disease↗
PubMed1980

Recurrent hepatitis caused by two viruses acquired simultaneously during blood transfusion.

We here report 2 patients who have acquired two consecutive episodes each of acute hepatitis, within 6 months after blood transfusion. The clinical and biochemical course was typical of recurrent acute viral hepatitis, and the patients recovered completely after each episode. The first infection was probably caused by non-A, non-B hepatitis virus, whereas the second episode was caused by hepatitis B-virus. Thus, in addition to the absence of cross-immunity between hepatotrophic viruses, one may simultaneously acquire more than one virus without apparent interference.

Aged↗
PubMedDate not supplied

Inaccuracies in estimates of life expectancies of patients with bronchial cancer in clinical decision making.

Approximations of life expectancy in clinical decision making frequently assume constant disease-specific ("excess") mortality hazards over age at diagnosis and over time from diagnosis. This assumption is inconsistent with the longer relative survival of younger patients with bladder cancer and with the declines in mortality hazards from bladder and breast cancers over time from diagnosis. To estimate the error that may result from these assumptions, the authors derived excess mortality hazards from the Surveillance, Epidemiology and End Result (SEER) tumor registry for bronchial cancers stratified by age at diagnosis and time from diagnosis. They compared the life expectancies calculated by a model using an average constant annual cancer-specific mortality hazard over time from diagnosis with those calculated using data-derived cancer-specific annual mortality hazards that varied as a function of time from diagnosis. For younger patients with less advanced disease, the constant-average-mortality model underestimated life expectancies by up to 50% relative to those predicted by the time-variant model. For those over 75 years old at diagnosis, and for all patients with advanced disease, the constant-average-mortality model overestimated life expectancies by up to 65% relative to those predicted by the time-variant model. The authors conclude that predictions of life expectancy with bronchial cancer, and probably with other neoplasms, are limited by the widespread use of oversimplified methods of calculation and by the lack of data describing mortality hazards as a function of time from diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗