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61.
Clinical observations have suggested that estrogens are involved in the pathogenesis of postmenopausal osteoarthritis (OA). However, positive and negative associations between the incidence of OA and serum estrogen concentrations have been reported. In contrast to this, osteoporosis is regarded as a disease with a strong estrogen-dependent component. Moreover, there is an interaction between estrogen and calcium deficiency: calcium supplementation potentiates the effect of estrogen therapy. The present study was designed to investigate how estrogen deficiency affects the articular cartilage depending on calcium supply. The distribution of different types of glycosaminoglycans and collagens can be used as an indicator for extracellular matrix changes induced by estrogen deficiency. Different levels of dietary calcium were therefore fed to intact and ovariectomized G?ttingen miniature pigs for one year before articular cartilage was harvested. The histochemical staining for heavy sulfated glycosaminoglycans in the extracellular matrix of ovariectomized miniature pigs, especially of those fed with a low calcium diet, was stronger in comparison to intact animals. In intact animals type II-collagen was immunodetected in all zones of unmineralized and mineralized articular cartilage, while immunostaining for this protein was negative to weak in the deep radiated fiber zone of ovariectomized minipigs. These results suggest that the synthesis of heavy sulfated glycosaminoglycans and immunohistochemically detectable type II-collagen is possibly influenced by estrogen deficiency. In conclusion, under estrogen deficiency, the extracellular matrix of articular cartilage underwent similar changes to those observed in physiologically aging cartilage where keratan sulfate is increased as a heavy sulfated glycosaminoglycan.  相似文献   
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Patients suffering from atopic eczema (AE) often exhibit disturbances of various neurovegetative (in particular, vasomotoric) skin functions. Thus, in 21 patients with AE we studied the response of the skin of one forearm to standardized 15-min exposure of the other arm to a cold and a warm bath (17 degrees-18 degrees C and 40 degrees-41 degrees C respectively). The results were compared with those in 23 age- and sex-matched healthy controls under similar environmental conditions. In most patients, during exposure of one forearm to warmth the skin temperature of the contralateral forearm remained unchanged or decreased slightly, whereas exposure to cold induced either a slight rise in skin temperature or an almost indiscernible decrease. In contrast to the normal temperature reaction of the non-exposed forearm to warmth exposure of the contralateral arm in most controls, our findings in atopic patients indicated a "rigid" or even "paradoxical" response to thermic stimuli. This abnormal pattern of thermoregulation may reflect an intrinsic disturbance of the peripheral and hypothalamic autonomous system involved in the pathogenetic conditions of AE.  相似文献   
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The epoxy groups contained in the cuticles of some plant species covalently bind residues of chemicals having a carboxyl function. This may lead to an increased persistence of these compounds in the environment. In order to assess the ecotoxicological potential of this reaction, an analytical method for the determination of cuticular epoxides was developed. Stable derivatives can be quantitatively formed by treating cuticles with 0.2M HC1 in 1,4-dioxane. This reaction leads to the formation of the corresponding chlorohydrins. It proceeds rapidly and without side-effects both in isolated cuticles andin situ. The derivatives can be analyzed by standard thin-layer and capillary gas Chromatographic methods. Electron impact and chemical ionization mass spectrometry was used to identify the chlorohydrins derived fromClivia andFicus leaf cutin.  相似文献   
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Thorsten Sch?fer 《Infection》1992,20(6):312-312

Information

1992 science award of the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V.  相似文献   
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Zusammenfassung Anhand von 115 im Zeitraum von 2 1/2 Jahren beobachteten Episoden von akutem Kreislaufstillstand bei 90 Patienten werden die Kriterien und Behandlungserfolge der Intensivtherapie des akuten Kreislaufstillstandes dargelegt. Während die Basis-Therapie mit externer Herzmassage, künstlicher Beatmung, Natriumbicarbonatinfusionen und elektrischer Defibrillation eindeutig feststeht, bietet die medikamentöse Führung noch immer Probleme. Zehn eigene Verlaufsbeobachtungen zeigen, daß betaadrenergische Sympathomimetica auch bei bestimmten Fällen tachysystolischer Herzrhythmusstörungen günstig wirken. Der Versuch der elektrischen Stimulation des Herzens mit einer extern angelegten epikardialen Schrittmachersonde bei akutem Kreislaufstillstand durch Asystolie oder Bradykardie führte in keinem von 8 Fällen zum Erfolg. Für die Früh- und Spätprognose sind bei adäquater Therapie in erster Linie Art und Schwere des Grundleidens sowie der morphologisch funktionelle Zustand lebenswichtiger Organe bei Einsetzen des plötzlichen Kreislaufstillstandes verantwortlich. Bei Kammerflimmern und Kammerflattern waren deutlich bessere Resultate zu erzielen, als beim akuten Kreislaufstillstand durch Asystolie. Von den 90 Patienten überlebten 12 länger als 4 Wochen (13%), 9 (10%) konnten entlassen werden und sind zum Zeitpunkt der Publikation ohne Nachwirkungen des akuten Kreislaufstillstandes. Es wird auf die Bedeutung einer lückenlosen Beobachtung Schwerstkranker und die Beachtung prämonitorischer Zeichen zur Verhütung des akuten Kreislaufstillstandes hingewiesen.
Summary Criteria and therapeutic success of intensive therapy of cardiac arrests are evaluated in 115 episodes observed in 90 patients over a period of 2 1/22 years. While basic therapy with external cardiac massage, artificial ventilation, infusion of sodium bicarbonate and electrical defibrillation is generally agreed upon, the choice of further drugs is still problematic. It is shown in 10 cases that under certain conditions even in ventricular fibrillation and ventricular tachycardia beta-receptor stimulating drugs are indicated. Electrical stimulation of the heart by an external epicardial pacemaker was unsuccessful in all of eight cases with complete asystoly or bradycardia. Immediate and long term results of cardiac arrests with adequate treatment primarely depends on the extend of the underlying disease as well as on the condition of all vital organs at the time of onset of the arrest. Ventricular fibrillation and -flutter had a better prognosis than asystoly. Twelve out of the ninety patients lived longer than four weeks after the arrest (13%). Nine of these are still living at the time of publication with an observation time from three months to two years. The chance of improving therapeutic results with intensive care lie mainly in preventing rather than curing complications such as cardiac arrests.


Professor Dr.H. E. Bock zum 65. Geburtstag.  相似文献   
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