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Behaviour and the concept of "heritability" axioms of an ethological refutation.

This paper discusses the widespread use of heritability calculations in recent behaviour research including behaviour genetics. In the sequel, a radical criticism concerning the basic axioms of the underlying, more general concept itself is presented. The starting point for testing the proclaimed universal validity of this concept stems from a fictitious yet realistic example taken from learning research. The theoretical result, based on the application of the conventional reasoning in this field, states that developmental processes--and learning is only one specific case out of an immense number of similar behavioural mechanisms--can neither be adequately described nor causally explained with sufficient reliability within the context of the heredity paradigm. On the contrary, an inherent inconsistency of the concept itself when applied to behaviour processes is demonstrated. Finally, a conceptual alternative involving a systems-theoretical approach to the problem is presented: In such a perspective it is the concept of "cognition" which represents the adequate explanatory theorem--a theorem in which quantitative processing of "information" from the environment is clearly revealed to belong to a subordinate level of living organization.

Analysis of Variance↗

The problem of automation in animal development: confrontation of the concept of cell sociology with biochemical data.

The principles of automation in animal development, as previously inferred from the concept of Cell Sociology do not fit in well with the current concept of sequential genet derepression. A more adequate explanation for those principles has been found in the literature dealing with the biochemical aspects of differentiation. Since oocytes and embryonic cells contain a greater variety of mRNAs than differentiated cells, as well as many tissue-specific (luxury) substances, it is concluded that the diversification of tissues consists of a progressive selection of specific metabolic strategies, mediated by cell-to-cell contacts, from a broad range of pre-existing strategies. For each tissue, prior to its final determination, one luxury metabolic strategy is progressively intensified and becomes dominant. The others are either suppressed or maintained as latent metabolic strategies. The latter may on occasion become dominant again (transdifferentiation). These phenomena require a theory which considers gene regulation as the activation of otherwise repressed genes by specific activator RNAs. The high (apparently maximal) transcriptional activity on the lampbrush chromosomes may represent the synthesis of all the kinds of activator RNAs which are required for the reactivation of the genes during early development. A general conception is propounded of the automatism and programming of animal development, as inferred from the confrontation of these ideas with the concept of Cell Sociology.

Animals↗

Type-concept, higher classification and evolution.

A study is made of the history of the type and related concepts, from Greek Antiquity up to the present. It is demonstrated that the type-concept of eighteenth century biology was based on Leibniz's concept of substantial form, and was not related to a Platonic Idea, whilst it is now generally understood in the sense of model or norm. In the present paper, a type-concept is developed which includes ontogenetic and phylogenetic time and various evolutionary mechanisms. This type (an archetype) can serve as a model of the evolutionary potentialities of a taxon, and as a standard of higher classification. All classifications based on the same archetype, whether typological, numerical or phylogenetic, will be comparable, although not necessarily identical.

Biological Evolution↗

[Subject health concepts and health-related quality of life--is there a correlation?].

OBJECTIVES: The aim of this study was to explore associations between lay concepts of health, quality of life and the health-related evaluation of daily activities. METHODS: A total of 221 persons (patients from general practice and adult as well as young members of sporting clubs) participated in the study (response rate: 84%). RESULTS: Health was often defined as "highest value of life"; "normal functioning of body and soul" and "complete well-being". Many persons considered sports, sleeping and leisure time being highly important for their health. The single dimensions of quality of life were associated with some health-related evaluations of daily activities, e.g., bodily functioning and health-related evaluation of television. Dividing the sample into persons who did or did not consider a certain concept of health (e.g., well-being) to be highly important had the following consequences: The quality of life was associated with different evaluations of daily activities in different strata; this association was sometimes negative, sometimes positive in different strata; more variance was explained by dividing the sample into different strata. CONCLUSIONS: The often contradictory associations between evaluation of everyday activities, lay concepts of health and quality of life should warn us not to think of health concepts and health actions in form of linear relations. Rather, health promotion should be more stronger oriented towards the individual's life conditions and his or her attitude to health.

Activities of Daily Living↗

Applying the species concept to plant viruses.

Plant virologists who maintain that the concept of species cannot be applied to viruses argue their case in terms of an obsolete concept of biological species defined by gene pools and reproductive isolation and applicable only to sexually reproducing organisms. In fact, various species concepts have been used by biologists and some of them are applicable to asexual organisms. The rationale for applying the species concept in virology is that viruses are biological entities and not chemicals: they possess genes, replicate, specialize, evolve and occupy specific ecological niches. The following definition is proposed: a virus species is a polythetic class of viruses constituting a replicating lineage and occupying a particular ecological niche. Such a definition of the species category does not and cannot provide a list of diagnostic properties for recognizing members of a particular virus species. It should also be stressed that a single property such as an arbitrary level of genome homology or the extent of serological relationship always fails to establish membership in a polythetic class. A binomial system of nomenclature is advocated in which the vernacular English name of the plant virus is adopted as the species name and the group name is assimilated to the level of genus. Adoption of this system would ensure that a universal classification system based on the classical categories of species, genus, and family becomes possible for all viruses.

Phylogeny↗

The place of the CT scan in the three concept view (TCV) of the low back pain syndrome. A preliminary survey.

From the historical lines along which our thinking about low back pain developed, three concepts can be deduced: radicular, stenotic and axial. The patient with a low back pain syndrome (LBS) should be seen with this three concept view (TCV) in mind. Modern insight into the degenerative process of the low back supports this concept. The clinical syndromes illustrating these concepts, radicular syndromes, Neurogenic Peripheral Intermittent Claudication (NPIC), and axial low pack pain, can intermingle. To determine the place of the CT scan in the process of diagnosis of the LBS, we carried out a total of 56 CT-examinations on about 200 low back patients with various indications. The results are discussed. In addition to radiological suppositions, NPIC plays an important part in deciding whether or not to perform a CT scan.

Adult↗

Coding medical concepts: a controlled experiment with a computerised coding tool.

In clinical routine there is a growing need to encode medical concepts with available standard coding systems. The coding process can be time consuming and may significantly add to daily paperwork, particularly regarding patients with multiple diagnoses and in busy clinical environments with a high turnover of patients. We have developed a generic computerised encoding tool--the PADS encoder--to ensure rapid, correct and complete coding of diagnoses in daily routine. The tool is integrated into an electronic patient record system (PADS, Patient Archiving & Documentation System) and takes full advantage of the user friendly Macintosh interface. The tool was tested in a controlled experiment by 18 clinicians who encoded a total of 666 medical concepts in each protocol (study protocol vs. control). The following positive findings were significantly associated with the use of the computerised coding tool: the number of correctly encoded medical concepts was higher (99.55% vs. 86.1%), coding errors were lower (0% vs. 10.81%), more modifier codes were encoded correctly (increase by up to 43%), less coding errors were made (decrease by up to 43%), the overall rate of correctly encoded and complete main and modifier codes was increased by 31.27% (97.29% vs. 66.02%), coding time was reduced by 50%. This paper presents data to suggest that a computerised coding tool can produce more complete data of higher quality and can save time compared with the traditional approach to encode medical concepts.

Computer Communication Networks↗

[Testing, estimating, "significance"--concepts and terminology of medical biometry].

The justification for the application of medical treatments and diagnostic methods has gained importance during the last decades. Together with scientific argumentations also the concepts of medical statistics have found a wide-spread use and are nowadays indispensible tools for clinical research. In publications of clinical trials, epidemiological investigations and animal experiments p-values, statistical tests and confidence intervals help the reader to evaluate the significance and relevance of the provided results. A prerequisite is a clear understanding of the concepts underlying these methodological terms. This paper presents the basic concepts of medical statistics and demonstrates the conclusions that can be drawn with the aid of these concepts.

Animals↗

Intraindividual comparison of two different skin care conceptions in patients undergoing radiotherapy of the head-and-neck region. Creme or powder?

OBJECTIVES: This study evaluated for the first time in intraindividual comparison the conception of care with creme or powder. Acute skin reactions on the left and right side of the neck during symmetrically performed radiotherapy and subjective impairment were assessed. PATIENTS AND METHODS: Twelve patients receiving radiotherapy of the head-and-neck region up to 50, 60, 66 and 72 Gy, respectively, were asked to treat one side of the neck with creme, the contralateral side with powder after random assignment. Objective and subjective assessment and photodocumentation were performed at therapy onset and weekly during therapy. The photodocumentation provides an impressive course of acute skin reactions under these care concepts. RESULTS: Altogether we saw no relevant difference in favor of care with creme or powder according to objective as well as subjective assessment criteria (Figure 2 and 3). In this intraindividual comparison the results are independent from interindividual different sensitivity to radiotherapy, total dose or fractionation. Therefore the small patient number is a minor limitation for evidence. Our results are in accordance to trials comparing other care concepts. CONCLUSIONS: A relevant effect concerning onset and degree of acute skin reactions or differences in symptom relief could not be demonstrated. Both conceptions are to be regarded equal in terms of subjective symptom relief and in extent of acute skin reactions. The lack of differences may be explained by the fact that the underlying pathophysiological processes cannot be influenced by topical agents.

Adult↗

Sentinel node concept in breast cancer.

BACKGROUND/PURPOSE: It seems that there exists a specific lymph node center called sentinel node (SN) which appears to be the primary site of metastases. The sentinel node concept (SNC) is fundamentally based on the orderly progression of tumor cells within the lymphatic system. It is the most important new concept in surgical and radiation oncology. The purpose is to present the biological significance, the diagnostic and clinical basis of the sentinel node concept in breast cancer patients. MATERIAL AND METHODS: Lymphoscintigraphy and gamma probe biopsy is necessary to show predictable lymph flow to the regional sentinel node, to multiple sentinel nodes or unpredictable lymph flow to extra-regional sentinel nodes and for performing sentinel node procedure. The standard protocol for the evaluation of the sentinel node metastases consists of extensive histopathological investigation including step Hematoxylin & Eosin (H&E) stained sections and immunohistochemistry. RESULTS: A high rate of success of the identification of the sentinel node for breast cancer was reported. The presence or absence of metastasis in this node is a very accurate predictor of overall nodal status. The temptation to examine the sentinel node with the greatest possible degree of accuracy highlights one of the major problems related to sentinel node biopsy. The success of the sentinel node procedure depends primarily on the adequate functional capacity necessary for sufficient uptake to ensure the accurate identification. In negative sentinel-node patients a complete axillary lymph node dissection is avoidable. In sentinel-node positive patients and clinically negative patients a postoperative radiotherapy would permit an adequate tumor control. The last 2 procedures permit a low morbidity. In the actual TNM classification it was recently introduced a definition of a "pN0" patient based on sentinel node biopsy. New target volumes are defined for adjuvant radiotherapy or lymphatic basins could be spared from unnecessary irradiation. CONCLUSION: The sentinel node concept seems to revolutionize the treatment of early breast cancer. Biopsy of the sentinel node is a highly accurate, minimally invasive method of staging patients and can substantially reduce the morbidity and costs of treatment by avoiding unnecessary complete axillary lymph node dissection. The procedure may lead to a more justifiable approach to adjuvant therapy strategies with low complication rates. The identification of the individual lymphatic flow pattern would permit the irradiation of the individual locoregional lymphatic basin.

Breast Neoplasms↗

[The treatment of necrotizing otitis externa with a combination of surgery, antibiotics, specific immunoglobulins and hyperbaric oxygen therapy. Results of the Ulm Treatment Concept].

BACKGROUND: Even today, necrotizing otitis externa is still a life-threatening condition. The standard treatment concepts based on antibiotic therapy, topical treatment and--if necessary--surgical debridement of necrotic tissue, remain ineffective in many cases. In advanced stages, necrotizing otitis externa can therefore be expected to result in severe functional impairment or even a fatal outcome. PATIENTS AND METHODS: We describe our experience with a multimodal treatment concept that we have been using with great success at the Federal Armed Forces Hospital in Ulm since 1987. This treatment is based on four pillars: 1. Surgical debridement, 2. Use of a combination of antibiotics, and 3. Administration of specific immunoglobulins, accompanied by, 4. Hyperbaric oxygen therapy RESULTS: Over a period of more than 5 years 16 of the 22 patients treated on the basis of this multimodal concept remained free of recurrences. In addition, significant reductions in analgesic use and in the insulin doses needed by diabetic patients were possible. CONCLUSIONS: The treatment concept under scrutiny has proved particularly successful. The various modes involved and the results of this combined therapy are discussed.

Acinetobacter Infections↗

[Psychological stress in patients with environmentally-induced disorders. A comparison between self concept and expert assessment].

Environmental illnesses raise diagnostic and therapeutic conflicts in scientific discussions and clinical practice. When a patient's health-belief model, based on environmental origins, does not match that of the expert, the therapeutic relationship can be endangered. Our study investigates this discrepancy, which has not been empirically evaluated so far. Patient (n=61) and expert disease concepts were systematically investigated. Our results indicate that in cases in which both concepts are favourable, the patient suffered minor psychiatric disorders with stable psychic structures and the symptoms were associated with medical or environmental causes. If both concepts were unfavourable, a higher proportion of psychiatric disorders with unstable psychic structures were present. In the case of incongruent concepts, the expert evaluations allow a more accurate assessment of the psychiatric diagnoses, psychic states and the psychic attribution of somatic and psychic burden.

Adult↗

[Modular memory training for elderly adults: concept and evaluation].

We present a modular concept of a cognitive training relevant to the demands of everyday life of community dwelling older adults. The concept has three major advantages. First, it takes into account the current performance levels and needs of the trainees. Second, the training is economical in aiming at selecting the most effective training elements. Third, the concept allows the evaluation of single elements of the training. The application of this concept points at the importance of training content being relevant to trainees' everyday lives. Results indicate that training effectiveness depends on the starting level of performance and the cognitive domain being trained. Overall, the results demonstrate the possibility to maximize training gains of older adults by designing adequate trainings for well-defined subgroups of normal older adults.

Activities of Daily Living↗

Seed, dispersal, microsite, habitat and recruitment limitation: identification of terms and concepts in studies of limitations.

Recently, there is an increase in number of studies concerned with the effect of various types of limitations on species local population size and distribution pattern at the landscape scale. The terminology used to describe these limitations is, however, very inconsistent. Since the different terms often appear in conclusions of the papers, the inconsistency in their use obscures the message of these papers. In this study, we review the current uses of these terms, identify the basic concepts involved in the discussion of a limitation and link the concepts with the currently used terms. Finally, we discuss the experimental approaches used to assess the different types of limitations. We differentiated four basic concepts resulting from the combination of limitation by environment versus ability to grow and spread, and two spatial scales (local and regional scale). The two concepts at each spatial scale are expected to form a gradient of all possible combinations of the two respective types of limitations. In the considerations of various experimental approaches used to assess these limitations, we conclude that sowing experiments, i.e. seed addition into existing populations or seed introduction into unoccupied habitats, are the only reliable types of evidence for the different types of limitations.

Biodiversity↗

Concepts in biocompatibility testing of dental restorative materials.

Due to the diversity of adverse biological effects which might be caused by dental restorative materials, biocompatibility assessment cannot rely on a single test but has to be based on a planned and structured approach (concept). First, the possible harm evoked by the material, the known data, and suitable biological and other test methods available must be taken into consideration. Modern regulatory concepts require for this purpose the services of experts to propose the appropriate set of required tests for a given material. The use of standards is generally emphasized because of better comparability of the data. Other tests may be chosen if more appropriate. Modern scientific concepts of biocompatibility testing are based on the need for rapid and cost-effective test methods, avoiding animal tests whenever possible. While formerly in vitro experiments did not take into account the special clinical situation in which the material would be used, modern concepts try to simulate important parameters of the in vivo situation as closely as possible. This may be achieved, for example, by including suitable barriers between the material and the target cells, by constructing appropriate target cells, and by choosing clinically relevant markers for measuring the biological effects caused by the material. There are indications so far that through this approach the number of animal tests can be reduced. The use of these methods may also lead to a better understanding of the mechanisms behind the biological reactions (mechanistic approach) in describing the biocompatibility of dental restorative materials.

Animals↗

The Bad Oeynhausen concept of INR self-management.

BACKGROUND: A significant number of patients depend on the intake of vitamin K antagonists for prevention and treatment of thromboembolic events. The development of portable anticoagulation monitors has enabled self-testing and self-adjustment of anticoagulation therapy. OBJECTIVE: To describe the principles of a training course to learn INR self-management and to illustrate reliability of our concept. DESCRIPTION: The training is divided into an early postoperative training, an ambulatory training six months later, and a 24 hours care and consultation. According to our concept, each patient who depends on long-term anticoagulation therapy is able to learn INR self-management. Reliability of our concept has been proved in two prospective, randomized clinical trials. STUDY RESULTS: A study with 1,155 patients has demonstrated that INR values lie more often in the predetermined target range in the INR self-management group if compared to the conventional group (79.2% vs. 64.9%; P < 0.001). Moreover, this study has demonstrated that self-management can lead to a reduction of thromboembolism (1.5% vs. 2.8%; P < 0.05), and to a lower lethality if compared to conventional INR management (3.5% vs 6.0%; P < 0.025). A second study with 1,816 patients has confirmed that INR self-management results in a high percentage of INR values in the target range (76%), even though target INR-range is reduced and narrowed. Thus, low dose INR self-management did not increase the risk of thromboembolism while avoiding the zone of higher risk for bleeding, beginning from INR > 3.5. CONCLUSIONS: The Bad Oeynhausen concept of INR self-management is a promising tool to achieve low hemorrhagic complications without increasing the risk of thromboembolic complications. It can thus be successfully applied to patients with an indication for permanent anticoagulation therapy.

Anticoagulants↗

Pregnancy outcome in 242 conceptions after artificial insemination with donor sperm and effects of maternal age on the prognosis for successful pregnancy.

Four hundred four treatment courses of artificial insemination with donor sperm were initiated in 330 couples. A treatment course was defined as completed if the patient conceived, failed to conceive after 12 cycles of artificial insemination with donor sperm, or dropped out of the program after at least one inseminated cycle. We have documented a 92.4% conception rate in patients who completed six treatment courses and 83.7% in those completing at least three treatment courses. Including all the patients who dropped out, 72.7% of all patients conceived. Spontaneous abortion occurred in 17.4%; three infants with major congenital defects were delivered and three indicated midtrimester abortions were performed. Our data demonstrate that the prognosis for successful artificial insemination with donor sperm is inversely related to advancing maternal age. Patients over age 35 had significantly lower conception rates; more insemination cycles were required per conception and the incidence of spontaneous abortion was related to the number of cycles required per conception.

Abortion, Spontaneous↗

The plan of the human face: a test of three general concepts.

In The Handbook of Facial Growth, Enlow proposes a series of anatomic concepts that account for "the plan of the human face." Three of those concepts are examined in this article, which presents measurements of 253 adult female primates from thirty-two species. As part of a system of craniofacial counterparts, Enlow proposes that the breadth of the mandibular ramus should equal the breadth of the pharynx. The relationship between ramus breadth and PNS-Ba in the primates studied strongly supports this hypothesis. A second concept tested concerns the relationship between prognathism and maxillary arch length. The relationship is not as strong as in the previous case, and some species are more prognathic than required for the size of their dentition. It is concluded that arch length and prognathism have an important biologic relationship but that the two features can vary with some independence. The third concept tested is the relationship between prognathism and interorbital breadth. Here the relationship is weak, and it is concluded that the interorbital breadth is not significant in setting a structural limit to the amount of facial prognathism.

Animals↗