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S Nahmias

Publications and source records attributed to S Nahmias.

8 recordsLinked to original sources
PubMed2001

Hemicrania continua is not that rare.

BACKGROUND: Hemicrania continua is an indomethacin-responsive headache disorder characterized by a continuous, moderate to severe, unilateral headache. More than 90 cases of hemicrania continua have been reported, but there is still uncertainty about its clinical features. METHODS: The authors compared 34 new cases (24 women, 10 men) with previously reported cases. All the patients met Goadsby and Lipton's proposed criteria. The authors compared baseline (continuous background headache) and exacerbation (attacks of severe periods of headaches). RESULTS: The baseline headache was typically mild to moderate in intensity and usually not associated with severe disability. In contrast, the headache exacerbations were severe and associated with photophobia, phonophobia, nausea, and disability. At least one autonomic symptom was present in 25 patients (74%). Jabs and jolts were present in 14 patients (41%). The mean indomethacin dose was 136.7 +/- 60 mg (range 25 to 225 mg). Twenty-four patients (70.6%) met International Headache Society criteria for migraine in their exacerbation period. Occipital tenderness was observed in 23 patients (67.6%). The temporal pattern was remitting in four patients (11.8%), continuous from onset in 18 (52.9%), and continuous evolving from remitting in 12 (35.3%). CONCLUSION: Hemicrania continua is not a rare disorder. All cases of chronic unilateral daily headaches should receive an indomethacin trial early if not first in treatment.

Adult↗
PubMed1990

Screening strategies to inhibit the spread of AIDS.

In this paper we explore the costs and benefits of screening programs for the human immunodeficiency virus (HIV). Because of the low prevalence rate of the virus among the general population, the cost per detected case of a program to screen the population at large is very high. We show how this cost changes with the prevalence rate, and how screening high risk groups reduces the cost per detected case. Screening has little point, however, unless there are follow-up activities to reduce the continued spread of the virus. To this end, we present a modeling framework for determination of optimal policy alternatives after screening.

Acquired Immunodeficiency Syndrome↗
PubMed1983

Effect of retinol and retinoic acid on P/O ratios of coupled mitochondria.

Retinol at levels above 0.5 n moles/mg protein and retinoic acid at levels above 0.25 n moles/mg protein are shown to uncouple mitochondrial oxidative phosphorylation. Uncoupling is measured with the substrates ascorbate plus N,N,N',N'-tetra-methyl-p-phenylenediamine, succinate and beta-hydroxybutyrate. These experiments indicate that the uncoupling effects of retinol and retinoic acid are not site specific but likely are the result of the vitamin being a general membrane bilayer disrupting agent.

2,4-Dinitrophenol↗
PubMed1982

Effect of retinol and retinoic acid on permeability, electrical resistance and phase transition of lipid bilayers.

Retinol and retinoic acid have been incorporated into the artificial membrane systems, planar bimolecular lipid membranes and liposomes, and their effects on several membrane parameters have been measured. 1. Retinol and retinoic acid increased the permeability of egg lecithin liposomes to K+, I- and glucose when incorporated into the membranes at levels as low as 0.5 membrane mol%. Retinoic acid influenced permeability more than did retinol for each of the solutes tested. 2. Retinol and retinoic acid both decreased the electrical resistance of egg lecithin-planar bimolecular lipid membranes from 0.5 to 8 membrane mol%. Retinoic acid effected a larger change than did retinol. 3. Retinol and retinoic acid increased the permeability of dimyristoylphosphatidylcholine and dipalmitoylphosphatidylcholine liposomes to water at 1.0 and 3.0 membrane mol%. A larger effect on water permeability was measured for retinoic acid than for retinol. 4. Retinol and retinoic acid at 1.0 and 3.0 membrane mol% were shown to lower the phase-transition temperature of liposomes composed of dimyristoylphosphatidylcholine or dipalmitoylphosphatidylcholine. Phase-transition temperatures were monitored by abrupt changes in water permeability and liposome size associated with the transition. Retinoic acid lowered the phase-transition temperature of dimyristoylphosphatidylcholine liposomes more than did retinol, while both retinoids had almost the same effect on dipalmitoylphosphatidylcholine liposomes.

Dimyristoylphosphatidylcholine↗
PubMedDate not supplied

Perishable inventory theory: a review.

This paper reviews the relevant literature on the problem of determining suitable ordering policies for both fixed life perishable inventory, and inventory subject to continuous exponential decay. We consider both deterministic and stochastic demand for single and multiple products. Both optimal and suboptimal order policies are discussed. In addition, a brief review of the application of these models to blood bank management is included. The review concludes with a discussion of some of the interesting open research questions in the area.

Blood Banks↗