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PubMedDate not supplied

[Higher mental functions and the systems analysis of behavior under conditions of uncertainty].

Superior psychical functions (skills) are usually formed in great subjective uncertainty conditions. Because of that exact knowledge of information mechanisms of behavior activity under uncertainty conditions is very importent. Some difficulties of traditional notions (classic behavior act model developed by P. K. Anokhin, systems quantization of behavior) are discussed. The model of probabilitive training allows to describe various training uncertainty conditions, and it operates as the Anokhin model in a specific case. The system-shaping factor in this model is an adaptive result. Afferent synthesis, aim for action, acceptor of the action result and the programme of actions have the traditional senses. Besides those it is proposed to use a concept of probability decision to alter the program of action, as well as an idea of memory buffer (results of search reactions). The organizational features of the functional system of behavior under great uncertainty conditions should be taken into account while specifying the informational mechanism responsible for systems quantization of behavior. The above mechanism can be used for explain the discreteness of an action in the program alteration process when the same quantum of behavior is implemented. These ideas are profitable for systems analysis of superior psychical functions, based on the reflex formation under environmental uncertainty conditions.

Animals↗
PubMed1997

Effects of Whole Blood Viscosity on Atherogenesis.

There is a high correlation between high whole blood viscosity and the well known risk factors for arterial occlusive disease: hypertension, hyperlipidemia, diabetes, male sex, age, smoking, and obesity. These risk factors increase whole blood viscosity, whereas the preventive factors of arterial occlusive disease such as fish oil, aspirin, alcohol, and exercise probably tend to reduce whole blood viscosity. The protective adaptation theory recently presented by Kensey and Cho1 proposed high whole blood viscosity as one of the major factors that make up the mechanical injury possibly inducing arterial occlusive disease. New diagnostic and prophylactic treatments for arterial occlusive disease are suggested. An accurate, convenient, and cost-effective blood viscometer that can be used in a clinical environment might become a useful diagnostic screening device for patients at risk for arterial occlusive disease, and it would help discover new prophylactic treatments.

Journal Article↗
PubMed2001

[Sweet syndrome: personal experience and review of the literature].

The Sweet's syndrome or acute febrile neutrophilic dermatosis is a well characterized cutaneous disease frequently associated with inflammatory and neoplastic diseases, particularly haematologic malignancies, and usually precedes the underlying disorders for months or years. Much of the evidence for this is based on case reports, small series of cases and reviews of the literature. Recently, immunologic theories suggest that the pathogenesis of Sweet's syndrome is probably mediated through helper T cell type 1 cytokines (IL-2, gammaINF) rather than helper T cell type 2 cytokines (IL-4). This results in the stimulation of a cytokine cascade, which might be responsible for the local and systemic activation of neutrophils and histiocytes. Clinically, Sweet's syndrome is characterized by the acute onset of an eruption of painful erythematous or violaceous plaques or nodules with fever, malaise, neutrophil leucocytosis and a raised erythrocyte sedimentation rate. Personal experience in 4 cases observed during five years is described. All of them presented diagnostic criteria of this disease and had a good response to corticotherapy and/or indomethacin. A review of the literature on this uncommon syndrome is also reported.

Adult↗
PubMedDate not supplied

[Case study--relationship between prevalence of shyness, social phobia and avoidant personality in male sexual disorders].

UNLABELLED: Social phobia, avoidant personality disorder and shyness are very akin disorders, despite the fact that the first two are mental disorders, whereas the third is found mainly in lay or psychological literature. The relationship between these disorders and male sexual disorders can only be hypothesized from clinical studies and psychopathological theories. Social phobia, avoidant personality disorder, and shyness, share a probable indirect responsibility in sexual disorders because they impair the ability of subjects to meet partners. There are only a few direct studies of the negative impact of shyness on sexual behavior. OBJECTIVE: The objective of this study was to compare males with sexual disorders to non-sexual disorder males on diagnosis of social phobia, avoidant personality disorder and shyness. METHODS: We conducted a case-control study comparing a group of male patients seeking care for sexual disorders (n = 87) and a control group of male subjects without sexual disorder (n = 87), regarding the diagnosis of social phobia, avoidant personality disorder and shyness. Diagnoses were appreciated with a structured diagnostic interview (CIDI for the diagnosis of social phobia) or a list of criteria (DSM IV criteria for avoidant personality disorder) and through standardized scales (Fear Questionnaire, CBSHY, Cottraux male sexual problems questionnaire). Severity of shyness was evaluated through visual analog scales. RESULTS: We found strong significant statistical differences between cases and controls regarding the percentage in each group of social phobia, avoidant personality disorder and shyness. For shyness, the mean score at CBSHY was 16.2 (+/- 12.63) for the cases and 6.07 (+/- 6.67) for the controls (p < 0.0001), whereas the percentage of cases with a score of > 19.5 was 41.4% vs 6.9% for the controls (p < 0.001); 27.6% of the cases had a CIDI diagnosis of social phobia vs 8% of the controls (p < 0.001); 31% of the cases implemented DSM IV criteria for the diagnosis of avoidant personality disorder vs 6.9% of the cases (p < 0.001). CONCLUSION: Our results are in favor of one or several factors in common between social phobia, avoidant personality disorder and shyness, which would be strongly related to male sexual disorders.

Adult↗
PubMed2000

[The triumph of China China]

Malaria and its various remedies were frequently debated by Italian scientists in the 17th and 18th centuries. Physicians of the period discussed the probable origin of the disease, making use of the humoral theory, whilst upholding the efficacy of a new remedy, the bark of the cinchona tree. Knowledge of malaria, the various pathogenetic theories and some quite bizarre therapeutic attempts are amply documented in the medical literature of the age.

Journal Article↗
PubMed1991

Automated selection of clinical data to support radiographic interpretation.

Modern computerized hospital information systems can store much of the clinical information required for patient care. In some settings the amount of this information is great enough to interfere with its efficient use. Supplying information in support of radiographic interpretation provides an example of this problem. We describe an automated process that abstracts select data from a clinical database and creates a report recounting salient facts designed to assist the radiologist in interpreting the chest x-ray. The reporting system selects data using a combination of expert systems technology and information theory. It produces a brief summary of relevant clinical data. The original version of this process required run-time use of expert systems techniques that were time-prohibitive in the clinical setting. Through the use of pre-compiled tables of finding specific information contents we have reduced the time requirement to a point where the applications will soon be clinically feasible.

Databases, Factual↗
PubMed1991

Exploring a new best information algorithm for Iliad.

Iliad is a diagnostic expert system for internal medicine. One important feature that Iliad offers is the ability to analyze a particular patient case and to determine the most cost-effective method for pursuing the work-up. Iliad's current "best information" algorithm has not been previously validated and compared to other potential algorithms. Therefore, this paper presents a comparison of four new algorithms to the current algorithm. The basis for this comparison was eighteen "vignette" cases derived from real patient cases from the University of Utah Medical Center. The results indicated that the current algorithm can be significantly improved. More promising algorithms are suggested for future investigation.

Algorithms↗
PubMed1991

Record linkage strategies. Part I: Estimating information and evaluating approaches.

Record linkage techniques can help identify the same patient for matching diverse files (hospital discharge abstracts, insurance claims, registries, Vital Statistics data) which contain similar identifiers. Prior knowledge of whether a linkage is feasible is important to prevent wasted effort (additional data collection or data manipulation), which decreases the cost-effectiveness of the linkage. Using examples generated by linking the Manitoba Health Services Commission data with Vital Statistic files, a method of estimating the information in each data set is presented first. Further, the feasibility of several different record linkage strategies is described and tested, given varying amounts of information. At the margin, relatively small amounts of information (having just one more variable to match with) can make a great difference. Probabilistic linkage's great advantage was found in those situations where only a moderate amount of extra information was available. By using the above techniques when working with one or both files in a proposed record linkage project, a much more informed judgement can now be made as to whether a linkage will or will not work. In facilitating record linkage, flexibility of both software and the strategy for matching is very important.

Data Collection↗
PubMed1988

Pneumo-retroperitoneum associated with pneumatosis cystoides intestinals.

Pneumatosis cystoides intestinalis, a rare disease characterised by gas cysts involving portions of the intestinal tract, is obscure in its etiology and intriguing in its presentation. Amongst several theories a new concept suggest that retroperitoneal gas is a probable source of origin. Experimental studies in animals have demonstrated that air can track down the mediastinum into the retroperitoneum and thereby into the gut wall from an alveolar rupture. A case of pneumo-retroperitoneum in a patient with pneumatosis cystoides intestinalis is now reported.

Aged↗
PubMedDate not supplied

Use of Rogers's conceptual system in research: comments.

This exposition examines testing of Rogers's theoretical constructs in the unitary man model, reflecting upon one published research article. It addresses two critical points of importance: (1) adequacy and appropriateness of the logic used to derive the research hypotheses; and (2) appropriateness of the research methodology used to test Rogers's model. This analysis indicates that interpretations of the principles of homeodynamics require a careful attention to the model's basic premise of evolution, noncausality, and probability. Operationalization of concepts for an empirical testing of the theory also requires an adherence to the basic premise of wholeness, that is, the unitary nature of human field. It also points out a serious shortcoming in the inferential power of research findings from animal studies for explanations of human phenomena within the context of Rogers's model.

Animals↗
PubMedDate not supplied

[Clinical research in psychiatry. Future prospects].

Psychiatry becomes everyday more scientific: inter-rater reliability improves constantly, thanks to the development of more rigorous methods. Diagnostic classifications make real headways: the gap between ICD-9 and DSM-III will certainly be reduced in the next few years. For instance, the introduction of sub-categories of anxiety states (or anxiety neuroses), such as panic disorder and generalized anxiety disorder, implies different treatment choice, and clarification in therapeutic indications. The same will happen probably soon for schizophrenic disorders and major affective disorders. Conflicting theories of organogenesis versus psychogenesis may not be so conflicting when we understand better how environmental signals and subjective experiences alter transmitter levels, receptors, and synaptic regulations.

Humans↗
PubMedDate not supplied

A simple coding procedure enhances a neuron's information capacity.

The contrast-response function of a class of first order interneurons in the fly's compound eye approximates to the cumulative probability distribution of contrast levels in natural scenes. Elementary information theory shows that this matching enables the neurons to encode contrast fluctuations most efficiently.

Animals↗
PubMed1998

Hydrodynamic shear shows distinct roles for LFA-1 and Mac-1 in neutrophil adhesion to intercellular adhesion molecule-1.

The binding of neutrophil beta2 integrin to intercellular adhesion molecule-1 (ICAM-1) expressed on the inflamed endothelium is critical for neutrophil arrest at sites of tissue inflammation. To quantify the strength and kinetics of this interaction, we measured the adhesion between chemotactically stimulated neutrophils and ICAM-1-transfected mouse cells (E3-ICAM) in suspension in a cone-plate viscometer at shear rates typical of venular blood flow (100 s-1 to 500 s-1). The kinetics of aggregation were fit with a mathematical model based on two-body collision theory. This enabled estimation of adhesion efficiency, defined as the probability with which collisions between cells resulted in firm adhesion. The efficiency of beta2-integrin-dependent adhesion was highest ( approximately 0.2) at 100 s-1 and it decreased to approximately zero at 400 s-1. Both LFA-1 and Mac-1 contributed equally to adhesion efficiency over the initial 30 seconds of stimulation, but adhesion was entirely Mac-1-dependent by 120 seconds. Two hydrodynamic parameters were observed to influence integrin-dependent adhesion efficiency: the level of shear stress and the intercellular contact duration. Below a critical shear stress (<2 dyn/cm2), contact duration predominantly limited adhesion efficiency. The estimated minimum contact duration for beta2-integrin binding was approximately 6.5 ms. Above the critical shear stress (>2 dyn/cm2), the efficiency of neutrophil adhesion to E3-ICAM was limited by both the contact duration and the tensile stress. We conclude that at low shear, neutrophil adhesion is modulated independently through either LFA-1 or Mac-1, which initially contribute with equal efficiency, but differ over the duration of chemotactic stimulation.

Animals↗
PubMed1998

[Nephrotic syndrome. What is new since the 1988 study?].

The authors make a retrospective review of 53 new cases of Nephrotic Syndrome followed up in the Nephrology Unit from November 1988 to March 1994, bearing in mind the evaluation of casual changes of the disease standard regarding a previous study of 1988. Epidemiological, clinical, therapeutical and evolutional aspects were studied. Forty-four cases of primary Nephrotic Syndrome (83%) were identified, 61.4% of which behaved as cortico-sensitive, 25% as cortico-dependent, and 13.6% as cortico-resistant; 8 cases (15%) of Nephrotic Syndrome secondary to infection, Systemic Lupus Erythematosus and Amyloidosis, and 1 case of congenital Nephrotic Syndrome (2%). The theory that the high number of cortico-dependent is, probably, related with a higher severity in the relapse diagnosis and/or changes in the children's standard of living is admissible. It was also observed that at present there is a lower number of hospital discharges, related to more careful attitudes adopted regarding the evolution of the disease.

Adolescent↗
PubMed1991

The structure of genealogies and the distribution of fixed differences between DNA sequence samples from natural populations.

When two samples of DNA sequences are compared, one way in which they may differ is in the presence of fixed differences, which are defined as sites at which all of the sequences in one sample are different from all of the sequences in a second sample. The probability distribution of the number of fixed differences is developed. The theory employs Wright-Fisher genealogies and the infinite sites mutation model. For the case when both samples are drawn randomly from the same population it is found that genealogies permitting fixed differences are very unlikely. Thus the mere presence of fixed differences between samples is statistically significant, even for small samples. The theory is extended to samples from populations that have been separated for some time. The relationship between a simple Poisson distribution of mutations and the distribution of fixed differences is described as a function of the time since populations have been isolated. It is shown how these results may contribute to improved tests of recent balancing or directional selection.

Base Sequence↗