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PubMedDate not supplied

[Methodology of a scientific study: from the formulation of the problem to the interpretation of the results--applications to radiology].

A scientific article should convey valid information to the reader. To reach this goal, the article must meet several criteria. First, the problem must be clearly stated. For example with medical imaging, the two types of studies are: -a descriptive study depicting a particular situation; -a comparative analytical study, either evaluating a diagnostic method or searching for prognostic factors. The process of defining the sample population can be distinguished: -Experimental studies can compare two groups of people who, after drawing lots, received differential treatment. -Alternatively, observational studies can investigate either representative samples, exposed versus nonexposed cases, or control cases. Characteristics of the variables are very important. Statistical methods facilitate the analysis of three types of variables: qualitative, quantitative and survival variables. Statistical analysis is used to extrapolate the results of the sample population of the study to the target population. Then, presentation, interpretation and extrapolation of the results must be done using three methods: First, the descriptive study should accurately depict the disease. It must be representative of the pathology relative to the clinical manifestations and avoid any bias. Then, the comparative analytical study for revealing the prognostic factors. These types of studies can be divided into three steps: -by performing the suitable statistical tests, a significant correlation between the prognostic factors and the outcome of the disease can or cannot be demonstrated; -any bias must be eliminated; -this correlation can be quantified by measuring it as a risk; Finally, the evaluation of the diagnostic methods are mostly used in medical imaging to determine which factors need to be measured. Five criteria can be followed for these types of studies: -to obtain good technical quality; -to interpret the results consistently; -to give valid information (requiring proper classification of the clinical signs of the patients according to the definition of disease); -to be helpful in determining the treatment; -to be efficient for the patient and the population. The results of a study on the diagnostic value of a medical test must be expressed as an index of sensitivity, or the rate of true positives versus negatives. This facilitates the calculation of the positive predictive value, i.e. the probability for a patient to become ill if the medical test is positive, versus the negative predictive value, i.e. the probability for a patient to remain healthy if the test is negative. The rigorous methodology of scientific work requires: -clear formulation of the problem; -good definition of the situation and the variables to be measured; -the proper method to collect the data; -the description of the study protocol.

Bias↗
PubMed1990

[Prevention and reduction of sensory and motor disorders in childhood. Formulation of the problem].

At present the Scientific and Research Laboratory of Preventive and Social Medicine is concerned with an extensive longitudinal research "Detection and reduction of sensory and motor disorders". Specialists from various paediatrics disciplines and some 200 health community paediatricians from six districts on the CR and SSR participate in the research. The research comprises children born in these districts in one calendar year. In part 1 the authors give an account of the basis formulation of the research problem and its incorporation within a wider framework. The aim of the research is to reduce the incidence and prevalence of sensory and motor disorders or to test techniques of the early detection of symptoms which signalize the risks of various affections, and to create prerequisites for further improvement of the programme of preventive care of the child population.

Child↗
PubMed1987

[A complex medico-genetic study of West Siberian populations. I. Formulation of a problem. Goals and objectives of the study. Population genetic characteristics of Northern Khanty].

Purposes and tasks of the complex medical and genetic study of West-Siberian inhabitants were formulated. Demographic parameters for the North Khanty inhabitants, such as size, dynamics of the tertiary sex ratio, marriage structure and migration processes were presented. Mating and intrapopulation migration patterns are determined by spatial subdivision, because of the vast territory and the traditional way of life, and by isolation by distance. Index of the isolocal endogamy equals to 0.364. The portion of mixed marriages is 22.7% and that of the gametic contribution of immigrants - 7.3%. Inbreeding coefficient by isonymy is 0.00097. Effective population size of the five subpopulations studied as a whole is 25% of their total number.

Consanguinity↗
PubMedDate not supplied

Experience of cognitive behaviour therapy in psychiatric practice in Nigeria: II: Illustrative case histories.

In order to give practical guidance to interested therapists, the author uses four illustrative cases to show how the technique of cognitive behaviour therapy can be applied in the clinical setting in Nigeria. First, a detailed cognitive assessment of the predisposing, precipitating and perpetuating factors associated with the presenting complaints is carried out. This helps the patient to realise that the symptoms are predictable, and therefore potentially surmountable. Second, the patient and therapist jointly formulate the problem in a few itemised statements. Third, the patient and therapist jointly articulate a set of cognitions (statements of insight) by which the problem in each formulated statement can be overcome. Fourth, as homework exercises, the patient affirms the set of cognitions at least twice daily, as if instructing him/herself (self-instructional training). This helps to make the insights received in therapy sessions to become deeply ingrained in consciousness, and positively affect behaviour in ordinary circumstances of daily living. Finally, a "diary of daily transformation" is articulated, with which the patient monitors the self, in order to see that insights obtained are applied in daily living experience. Educated, articulate and committed patients with circumscribed psychological problems can achieve significant improvement in 3-20 weekly sessions.

Adult↗
PubMed1993

An accelerative enumeration algorithm for the bottle combination problem and the menu planning problem.

In the clinical practice, there are a number of instances in which the request tailored to each patient must be satisfied with a combination of ready-made medical supplies. For example, in intravenous infusion and feeding, an appropriate combination of commercially available bottles must be chosen such that fluid, electrolyte, and nutritional requirements can be satisfied for the individual patient. Menu planning also has the same feature. However, the problem of the optimal combination of medical supplies is difficult to solve exactly and quickly even with the aid of the computer, because of the combinatorial nature of this problem. We formulate the combinatorial problem of medical supplies as a nonlinear all-integer programming problem and present a fast exact algorithm to solve the problem. The proposed algorithm is proved to find an optimal combination in an acceptable calculation time for medical problems of the usual size.

Algorithms↗
PubMed1987

Inhibition of intestinal diamine oxidase by detergents: a problem for drug formulations with water insoluble agents applied by the intravenous route?

One hundred and twenty four water-insoluble drugs were included in a study for their action on diamine oxidase (DAO) after solubilization with 61 detergents. 16 detergents were themselves not water-soluble and were not further investigated. A further 3 detergents affected the extraction procedure and 7 of the remaining 42 detergents themselves inhibited the activity of canine intestinal DAO in vitro. Only 5 detergents fulfilled all prerequisites for our DAO assay, including the solubilization of 76 water-insoluble drugs. Each of these 5 detergents had an individual range of suitability in our test system. 3/76 drugs inhibited DAO in concentrations up to 10(-3) M. This result is in contrast to our study with water-soluble substances, where 16% were DAO inhibitors. Since detergents can block the enzyme which is responsible for histamine catabolism, some of the observed adverse reactions to drugs could arise because of the presence of such detergents in the formulation.

Amine Oxidase (Copper-Containing)↗
PubMed1977

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↗
PubMed1981

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↗
PubMed1979

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↗
PubMed1990

[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↗
PubMed1977

[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↗
PubMed1986

[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↗