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Zusammenfassung Nach Zusammenstellung der einschlägigen Literatur, welche die Beziehung Anthrakose-Lungentuberkulose behandelt, wird ein Versuch unternommen, den Mechanismus der Kohlespeicherung durch die Lunge, und speziell die tuberkulöse Lunge im Tierversuch zu studieren.Es gelang im Serienversuch, eine an sich tödlich verlaufende Kaninchentuberkulose durch intravenöse Injektion einer besonders modifizierten Kohlenstaubsuspension zur Ausheilung zu bringen.Erklärt wird dieser überraschende Effekt dadurch, daß infolge der Reizung der Gefäßenthothelien (Uferzellen) durch die Kohlepartikelchen eine reichliche Abwanderung von Phagocyten in das Lungengewebe stattfindet. Die so modifizierten Speicherzellen treten offenbar in Beziehung zum Krankheitsherd.  相似文献   

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Glucose is the main energy substrate for blastocysts. It is utilized for ATP and macromolecule synthesis by glycolysis and the citric acid cycle. The less efficient utilization of glucose by anaerobic glycolysis may serve two purposes: lactate production for the maintenance of cytoplasmic redox equilibrium and adaptation to the low oxygen concentration in the uterine cavity during blastocyst development. In humans, the glucose concentration in uterine secretions seems to be in the same range as in blood. However, a more detailed analysis, especially in women with metabolic disorders, is still lacking. High glucose concentrations in vivo (animal models for diabetes mellitus) and in vitro lead to retardation of development, increased apoptosis, and higher embryonic mortality. Glucose deprivation without substitution of other energy nutrients does not allow development beyond the blastocyst stage in mammals. Glucose uptake by preimplantation embryos is accomplished by energy-independent facilitative transporter molecules, the glucose transporters (GLUT). Almost all presently known GLUT isoforms have been detected in preimplantation embryos, many of them in a cell-, stage-, and species-specific expression pattern. Most likely, the transport of maternal glucose into blastocysts is performed by the cooperative action of GLUT3 and GLUT1. Both isoforms are expressed in blastocysts from the species studied so far (mouse, rat, rabbit, cow). Therefore the question arises as to why, besides these two isoforms, at least four other isoforms are present in preimplantation embryos. Among them are the two insulin-sensitive isoforms GLUT4 and GLUT8. It is reasonable to speculate that GLUTs also exert developmental functions which are independent from glucose transport. These functions, however, are not yet clear. Glucose transporter expression is influenced by glucose and insulin-like growth factors (insulin, IGF-1, IGF-2). These IGFs and their receptors are essential parts of the embryo-maternal communication in early pregnancy. Well-known feedback mechanisms exist between the concentrations of glucose and IGFs and between them and GLUT expression. Because specific effects of IGFs on embryoblast cells have been reported, nonphysiological concentrations of glucose and IGFs may disturb the fine-tuned allocation of embryoblast and trophoblast cells during blastocyst formation and development, thus exerting a deleterious effect on pre- and postimplantation embryo development. Such effects may be taken into consideration when discussing the Barker hypothesis.  相似文献   

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Ohne ZusammenfassungVortrag gehalten in der mediz. Sektion der Schlesischen Gesellschaft für vater länd. Kultur zu Breslau.  相似文献   

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Zusammenfassung 1. Unter Einflu? von Insulin werden sowohl beim Normalen wie beim Diabetiker die Capillaren durchl?ssiger. 2. Es handelt sich dabei mit Wahrscheinlichkeit nicht um ein unmittelbare, sondern eine mittelbare Insulinwirkung.  相似文献   

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