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At least 181 records · Page 10Linked to original sources

Psychic dependence? A different formulation of the problem with a view to the reorientation of therapy for chronic drug addiction.

Disputing the concept of "psychic dependence", the authors review six motivations to use addictive drugs, four of which pertain to the moment of assumption of the habit, and two of which, identifiable with physical and psychic dependence, depend on breaking of the habit. While physical dependence is linked to withdrawal syndrome, psychic dependence, in the authors' opinion, is related to a longstanding previous state of true of masked endogenous depression (in this case it would be well termed "neuropsychological dependence"), and the drug taking is only a maladaptive self-medication. This thesis is substantiated by the literature reporting, in chronic drug addicts, the use of the whole series of antidepressants (i.e. tricyclics, doxepine, lithium, etc.) with noticeable therapeutical success. In accordance with other reports and with personal experience, the authors assign great importance to the drugs acting, directly or indirectly, on GABA, i.e. L-glutamine, piracetam, and, particularly, N-dipropylacetic acid.

Aminobutyrates↗

Problems with commercial formulations of 8-methoxypsoralen.

Plasma concentrations of 8-methoxypsoralen were measured in 8 psoriatic patients after administration of two commercial solid formulations and of an 8-methoxypsoralen solution. Systemic availability as measured by the area under the concentration versus time curve was much higher for the solution than for the two commercial formulations. For the solid formulations, a large inter- and intraindividual variation in plasma concentrations was found and in many cases no plasma levels could be measured. Administration of the solution gave always more reproducible plasma concentrations in function of time.

Absorption↗

Prediction models in small area estimation.

Finite population estimation problems are formulated as prediction problems under superpopulation models. For linear regression models, a general theorem on optimal linear estimation is presented. The theorem is applied to simple cross-classification models to generate and analyze various statistics for estimating small area totals. These statistics include the synthetic and composite estimators, as well as some interesting alternatives.

Humans↗

[Experimental microbiological research on instrument and denture disinfection with a disinfectant spray for dental practice and the use of patients. 1. The formulation of the problem and bacteriological studies].

Three disinfectant sprays (Arugeen, Desident and Fesia-sept) proved to be very efficient against pure cultures of aero bacteria species, Cand. albicans, saliva flora and entero- and influenza viruses. The methods included carrier experiments using denture basis resins, fragments of orthodontic appliances and screws (instead of instruments).

Aerosols↗

[Psychological dependence? A possible different formulation of the problem for a therapeutic rearrangement in chronic drug addictions].

Disputing the concept of "psychic dependence", the Authors review six motivations to use addictive drugs, four of which pertain to the moment to assume the habit, although the latter two, which are identifiable with physical and psychic dependence, depend on te breaking the habit. While physical dependence is linked to withdrawal syndrome, psychic dependence, on the Author's opinion, is related to a long-standing previous state of true or masked endogenous depression (in this case it would be well termed as "neuropsychological dependence"), and the drug taking is only a maladaptive self-medication. This thesis is substantiated by the literature, reporting, in chronic drug addicts the use of the whole series of antidepressants (i.e. tricyclics, doxepine, lithium, etc.), with noticeable therapeutical success. According with other reports and with personal experience, the Authors maintain a great importance to drugs acting, directly or not, on GABA, i.e. l-glutamine, piracetam, and, particularly, N-dipropilacetic acid.

Antidepressive Agents↗

[Various characteristics of gene localization in eukaryotic chromosomes. Formulation of a problem and analysis of non-random localization of mating type loci in fungi].

We have denoted two possible models of gene order evolution as the "card" and "chess" models. The first suggests random shuffling of genes during evolution, the second--non-random gene transposition, gene order being checked by natural selection. We discuss here localization of the mating type locus in fungal genomes. In 8 of 10 genetically well studied species of ascomycetous fungi, the mating type locus is linked to a centromere; in one species, it segregates regularly during the second meiotic division, and only one species does not show any regularity in the mating type locus segregation. Centromeric linkage of the mating type locus maintains heterozygosity of all centromeric genome regions during intratetrad fertilization observed in some fungi. Non-random localization of mating type locus can be considered as the means for conservation of heterozygosity.

Chromosome Mapping↗

[Retrospective estimation of the frequency of heterozygous beta-thalassemia in the Crimean Tartar population. Formulation of the problem. Estimation of the gametic contribution to a mixed population from frequencies of the ABO blood group genes].

Polymorphism of the beta-thalassemia gene frequency in non-indigenous populations of Central Asia, especially Crimean Tartars, is often explained by inter-ethnic marriages. The frequencies of these marriages, however, are not sufficient to produce the observed gene frequencies. Because of this, an estimation of the extent of Uzbek gametic contribution to the ethnic group of Crimean Tartar origin was conducted using data on the frequencies of ABO blood group genes. The maximum-likelihood estimate obtained (0.325) was used to determine the heterozygous beta-thalassemia frequency of the ancestral Crimean Tartar population.

ABO Blood-Group System↗