Search results for "Oxygen supply"
showing 10 items of 12 documents
Therapeutic Angiogenesis in Surgery and Oncology
1994
The aim of this presentation is to demonstrate the pathological importance of microenvironmental tissue hypoxia and to elucidate a general treatment concept for this situation which we have termed therapeutic angiogenesis 1. Hypoxia not only represents an insufficient oxygen supply for the cells of a given tissue area but is also regarded as an indicator for their metabolic deprivation and the concomitant accumulation of waste products. Therapeutic angiogenesis applied either with clinically established methods or using novel ways, which are the objectives of laboratory research and clinical trials at present, or in so far hypothetical forms, should lead to an expansion of the functional mi…
Practical Applications of Models of Oxygen Supply, Diffusion, and Consumption
1996
It is the objective of this paper to describe, what models of oxygen supply, diffusion, and consumption have been and can be used for and to discuss some common problems in employing mathematical models of O2 transport. In a first part, four typical fields for model applications are selected from the wide variety of former investigations and are illustrated with some recent examples.
Corneal Oxygen Supply Conditions
1976
Pronounced cornea hypoxia induces swelling and a loss of transparency. Hypoxia of longer duration causes necrosis, particularly of the corneal endothelium. These findings were observed after ligation of the cilial arteries and the arteria carotis interna, after reduction of oxygen tension on the anterior corneal surface as well as after prolonged wearing of ill-fitted contact lenses (11, 15, 18, 22, 23). Because the normal function of the corneal endothelium plays a central role in maintaining transparency, an insufficient endothelial oxygen supply can directly influence vision (3, 17).
Respiratory plasticity in response to changes in oxygen supply and demand
2011
Aerobic organisms maintain O(2) homeostasis by responding to changes in O(2) supply and demand in both short and long time domains. In this review, we introduce several specific examples of respiratory plasticity induced by chronic changes in O(2) supply (environmental hypoxia or hyperoxia) and demand (exercise-induced and temperature-induced changes in aerobic metabolism). These studies reveal that plasticity occurs throughout the respiratory system, including modifications to the gas exchanger, respiratory pigments, respiratory muscles, and the neural control systems responsible for ventilating the gas exchanger. While some of these responses appear appropriate (e.g., increases in lung su…
Microelectrode Measurements of Oxygen Tension Distributions in Multicellular Spheroids Cultured in Spinner Flasks
1984
Since multicellular spheroids were introduced into cancer research by Sutherland et al. (1970, 1971), they have been widely used for studying the susceptibility of cancer cells to various treatment modalities. Many of these investigations provided evidence for a major role of oxygen in controlling the metabolic and cell cycle state of the tumor cells, thus modifying the responsiveness of the cells to therapy. Several investigators have measured O2 tension (PO2) distributions in spheroids with O2-sensitive microelectrodes (Carlsson et al. 1979; Kaufman et al. 1981; Mueller-Klieser and Sutherland 1982a, b, 1983; Mueller-Klieser et al. 1983). The measurements produced PO2 values that varied co…
Effects of alirocumab on types of myocardial infarction : insights from the ODYSSEY OUTCOMES trial
2019
Gislason, Gunnar H/0000-0002-0548-402X; Malynovsky, Yaroslav V/0000-0002-9118-1104; Bhatt, Deepak L./0000-0002-1278-6245; Nikolaev, Konstantin/0000-0003-4601-6203; Sherwood, Matthew/0000-0002-4305-5883; Chumakova, Galina A/0000-0002-2810-6531; Raffel, Owen C/0000-0001-5470-7050; Leonardi, Sergio/0000-0002-4800-6132; Tse, Hung Fat/0000-0002-9578-7808; Reshetko, Olga/0000-0003-3107-7636; Pereira, Helder/0000-0001-8656-4883; Racca, Vittorio/0000-0002-4465-3789; Podoleanu, Cristian/0000-0001-9987-2519; Ersanli, Murat/0000-0003-1847-3087; Muenzel, Thomas/0000-0001-5503-4150; Sandhu, Manjinder/0000-0003-2538-2079; Taskinen, Marja-Riitta/0000-0002-6229-3588; bastos, jose/0000-0002-9526-3123; Manak…
Respiratory Gas Transport in Heart
1973
The purpose of this paper is to describe an attempt to obtain a better understanding of the dynamics of the oxygen supply of the myocardium under physiological and pathophysiological conditions by examining the oxygen diffusion in the heart muscle tissue during systole and diastole. In comparison to other organs the oxygen supply of the myocardium is characterized by a number of specific features. The most important one is that the gas exchange in the myocardium is a nonsteady-state diffusion process.
A welcome shortage of breath
2005
The respiratory systems of animals must guarantee an efficient oxygen supply. But it seems that, in some insects, they have evolved to restrict the flow of oxygen too.
Changes of Oxygen Supply to the Tissue Following Intravenous Application of Anesthetic Drugs
1973
The main function of the clinical anesthiologist is to make surgical treatment painless for the patient. For this purpose he uses drugs that severely interfere with the regulation of oxygen supply to the tissue. The same problem exists for the scientists working on animal experiments where he has to decide whether his experimental results were not changed by the anesthiological treatment.
HETEROGENEOUS OXYGEN TRANSPORT WITHIN MALIGNANT TUMORS
1981
Publisher Summary This chapter discusses the heterogeneous oxygen transport within malignant tumors. Many solid tumors disturbances in the vascularization and in the microcirculation generally lead to distinct restrictions in the convective and diffusive transport. Beyond that, a heterogeneous distribution of the transport conditions develops causing an insufficient and heterogeneous substrate supply as well as an inadequate drainage of wastes. As one of the compulsory manifestations, a poor and heterogeneous oxygen supply becomes more extensively evident with increasing tumor size or age. The polarographic measurements of the local tissue pO 2 values in animal tumors show that very low oxy…