PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “ADAPTATION, BIOLOGICAL”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 415 records · Page 23Linked to original sources

Adaptation and race.

Explore the source record for details and available documents.

Adaptation, Biological↗

[Pathomorphological studies of trichocephaliasis in sheep].

The morphologic study of 22 sucking and weaned lambs (8 experimentally and 14 spontaneously infected with Trichocephalus) revealed that in its biologic development in the host Trichocephalus fixes itself firmly and penetrates deeply at its head and into the mucous membrane of the caecum and the large intestine. Besides, at these sites morphologic lesions in cases of strong infection have been established in the liver, kidneys, spleen, and lung. The desquamated epithelial cells and the erythrocytes found in the digestive canal of the parasite showed that sheep Trichocephalus sp. are hematophages. The indented chitin cover and its morphologic peculiarities is a structural anatomic and biologic adaptation enabling the fixing and dependable adherence to the intestinal mucous membrane of the host.

Animals↗

[Changes in the state of the histamine--diamine oxidase and serotonin--monoamine oxidase systems and the activity of the sympatho-adrenal system following experimental occlusion of the aortic trifurcation in dogs].

Experiments on 12 dogs have shown that alterations in the intrasystemic parameters of histamine-diamine oxidase, serotonin-monoamine oxidase, adrenaline-noradrenaline and in the intersystemic patterns of adrenaline-histamine indicate the biological adaptation under conditions of embolism of aorta trifurcation induced by 3-hour occlusion. Alterations in the activity of the enzymes studied underlie the adaptational syndrome. During 6-hour occlusions the activity of monoamine oxidase was relatively decreased. Meanwhile the content of serotonin and noradrenaline remained at a high level. These amines might participate in the development of pronounced hypoxic impairments seen in the course of the observation period. It is recommended that adrenoblockers and inhibitors of synthesis of serotonin or serotonin-reactive structures may be used for correction of metabolic disorders.

Acute Disease↗

[Genetic and phylogenetic aspects of games and sports (author's transl)].

Games and sports have increasingly become a biologically necessary adaption reaction of man to his ever easier living conditions due to subjugation of the environment. "Physical performance", defined as the capacity of the individual to cope adequately with the physical and psychic demands of the environment and his career has doubtless played a great part in the phylogenetic development of man. Everything connected with it--and that is not only purely motor, but also corresponding esthesiophysiology and intellectual capacities--has contributed to a considerable extent to the selective formation of man.

Adaptation, Biological↗

Microvascular techniques in limb-sparing surgery.

Microvascular techniques allowing free tissue transfer have expanded the indications for limb salvage in tumor patients. Preoperative planning should predict the type of deficit anticipated. Specific techniques for soft tissue, skeletal, neurovascular, and composite tissue transfer are discussed. While demanding, the use of living autogenous tissue gives the potential for biologic adaptivity and life-long durability.

Adult↗

Shortening of patellar ligament and patella baja with improvement of quadriceps muscle strength after high tibial osteotomy.

One hundred and eight osteoarthritic knees that had high tibial osteotomy were examined, in the length of the patellar ligament, patellar height, and the strength of the quadriceps muscle. Patellar ligament shortening occurred until one year after surgery. Subsequently, shortening was not observed to be significant over a 10 year followup period. Using Insall-Salvati ratio, a majority of knees seemed to have lower patellae, because of the shortening of the patellar ligament. However, using patellotibial distance, 68 percent of patellae maintained the same height as preoperatively and 26 percent became patella baja. The strength of the quadriceps muscle increased postoperatively, reached the maximum at 2 years, and preserved the same strength over 10 years. Patellar ligament shortening and patella baja were probably thought to be caused by the biological adaptation of the extensor mechanism and the shrinking of the scar tissue in and around the postoperative patellar ligament.

Adaptation, Physiological↗

Hypothetical pathways of cardiac myocyte hypertrophy: response to myocardial injury.

The heart is made up of many different cell types, including myocytes, fibroblasts and vascular cells. The cardiac myocyte, although not likely to divide, may respond to gross organ injury by a process of growth or hypertrophy. Cellular hypertrophy, though a normal biological adaptation, has the potential to contribute to the change in the shape and the size of the heart, such as occurs in chronic heart failure. We are now just beginning to understand the signals and early pathways involved in the cardiac myocyte growth response, some of which are reviewed herein.

Animals↗

Language comprehension in ape and child.

Previous investigations of the linguistic capacities of apes have focused on the ape's ability to produce words, and there has been little concern for comprehension. By contrast, it is increasingly recognized that comprehension precedes production in the language development of normal human children, and it may indeed guide production. It has been demonstrated that some species can process speech sounds categorically in a manner similar to that observed in humans. Consequently, it should be possible for such species to comprehend language if they have the cognitive capacity to understand word-referent relations and syntactic structure. Popular theories of human language acquisition suggest that the ability to process syntactic information is unique to humans and reflects a novel biological adaptation not seen in other animals. The current report addresses this issue through systematic experimental comparisons of the language comprehension skills of a 2-year-old child and an 8 year-old bonobo (Pan paniscus) who was raised in a language environment similar to that in which children are raised but specifically modified to be appropriate for an ape. Both subjects (child and bonobo) were exposed to spoken English and lexigrams from infancy, and neither was trained to comprehend speech. A common caretaker participated in the rearing of both subjects. All language acquisition was through observational learning. Without prior training, subjects were asked to respond to the same 660 novel sentences. All responses were videotaped and scored for accuracy of comprehension of the English language. The results indicated that both subjects comprehended novel requests and simple syntactic devices. The bonobo decoded the syntactic device of word recursion with higher accuracy than the child; however, the child tended to do better than the bonobo on the conjunctive, a structure that places a greater burden on short-term memory. Both subjects performed as well on sentences that required the ability to reverse work order as they did on sentences that did not require this capacity. These results are discussed in light of a model of the evolution of language that suggests that the potential for language comprehension preceded the appearance of speech by several million years at minimum. The onset of speech is linked to the appearance of fully adapted bipedalism, which necessitated reorientation of the laryngeal tract and made closure of the soft palate possible. For the first time, such closure permitted mammals to easily produce sounds that could be interpreted by the mammalian auditory system in a categorical manner. When these sounds were paired with the previously extant capacity to produce vowels, it became possible to form "bounded vowels" or sound units that could readily be discriminated as units by the auditory system. It is suggested that this physical adaptation allowed the extant cognitive capacity of the hominids to embark on a speech-like mode of communication.

Animals↗

[Environmental medicine group diagnosis of children--studies from 1982 to 1990. Review].

In the period of 1982-1990 a total of 5760 children (2893 boys, 2816 girls) were examined in the frame-work of the Clean Air Programme Rhine-Main: from the polluted Rhine-Main area 2511 children (Wiesbaden 1682, Frankfurt since 1985, 825), from the control areas 3153 children (Freiburg area 1937, Starnberg area 1316). Healthy children living in the industrialised Rhine-Main area exhibited alterations of the following parameters compared with healthy children living in the less polluted control areas: Long-term alterations, enlarged and fissured, rough palatine tonsils, palpably enlarged cervical and mandibular lymph nodes, Short-term alterations, erythrocyte count: from 1981-1988 relatively smaller numbers, from 1988-1990 equalized to the scatter range of controls, hemoglobin values: corresponding to erythrocyte counts, activity of lymphocyte nucleoli: increased until 1985, later on equalized, lymphocyte count: reduced, T8-suppressor cell count: decreased, chemiluminescence of granulocytes: increased, palatine tonsils: altered microbial contamination with contact germs, altered physiological resident flora, heavy metals (Pb, Cd) in hair: from 1982-1990 increased, then slowly reduced corresponding to the results of the ambient air analyses. These findings indicate an increased inclination for reaction of the healthy juvenile organism in the sense of biological adaptation to long-term stress, i.e. living for years in an area with air pollution, and are also in good agreement with the measuring values characterising the ambient air quality.

Air Pollution↗

[Effect of major epidemics on cultural awareness].

Mankind has been stricken with "major" epidemic diseases throughout its history. The most serious among them immediately threaten man's life e.g. plague, cholera, smallpox, typhus, and dysentery, besides, there are others which take a slower course e.g. lues, leprosy, leishmaniasis, tuberculosis, and malaria. Yet, the "lesser" epidemic diseases like diphtheria, scarlet fever, mumps, pneumococcosis, influenza, and most recently AIDS may also turn into "major" ones. Originally, man exclusively depended on his genetic makeup for protection, and being particularly prone to attacks of disease he was subject to natural selection. Thus, only one human species survived, the homo sapiens. Interbreeding achieved biologic adaptation and created a balanced genetic polymorphism. Advancing in his degree of civilization, man formed groups, developed clothing, fire, houses, and tools, and his increasing cultural awareness allowed him to migrate from the tropical climates to more temperate, and less disease-infested zones. Immigration and wars, and the accompanying infections jeopardized and diminished entire populations and eradicated highly developed cultures like that of the American Indians. The plague, coming from Asia, and lues, from America, as well as cholera, influenza, and smallpox spread around the whole globe. Fear and terror led to irrational conclusions and triggered persecutions. The attitude of accepting disease as a God-sent fate (Hiob), or a God-sent punishment suppressed reasonable measures against disease. The necessary official measures have increasingly restricted liberty, and this patronizing treatment needs to be opposed with a higher sense of responsibility. Medical art has developed from more healing towards prophylactic and predictive medicine, which prognosticates the individual susceptibility to particular infections, and other risk factors.

Cultural Evolution↗

[Respiratory system involvement in pseudotuberculosis].

Clinical, microbiological, x-ray and immunological examinations of 1376 patients with pseudotuberculosis and 465 patients with acute respiratory diseases of viral or coccal origin, the trends in annual morbidity for the above diseases followed up within 7 years in the populations where the patients were registered and experimental investigations on rabbits provided evidence for primarily generalized pattern of pseudotuberculosis infection and a direct relationship between pulmonary lesions in the animals and effective dose of the infectant, route of the infection. The patients had nonspecific (non-yersiniosis) lesions of the respiratory system. Frequency of the infection was greater in cold seasons, especially in those who did not complete social and biological adaptation to new conditions, and depended on seasonal fluctuations of respiratory infection morbidity in nonrandom populations.

Acute Disease↗