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Summary Early lesions of arteriosclerosis are characterized by proliferating smooth muscle cells, macrophages, and foam cells. In addition, large amounts of connective tissue components and cholesterol esters are found. These changes are primarily located in the intima of the arterial wall. The initial mechanisms responsible for lesion formation are largely unknown. In recent years progress has been made particularly in fields of research related to the biochemistry of arterial wall cells in tissue culture. The findings obtained allow us to deepen our knowledge of the pathophysiology of arteriosclerosis. Of special interest are mechanisms involved in the maintenance of the thromboresistent endothelium, the factors triggering proliferation of intimal smooth muscle cells, and the transformation of macrophages to foam cells.
Diese Arbeit wurde von der Deutschen Forschungsgemeinschaft unterstützt (Sachbeihilfe HA 1083/2-2)  相似文献   
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This study investigated the testicular morphology as well as the gonadal and extra-gonadal sperm reserves of West African Dwarf (WAD) goats exposed to graded levels of 2,4-dichlorophenoxyacetic acid (2,4-D). Twenty male WAD goats of five goats per group were used for this study. Goats in groups A, B and C received low [75?mg/kg body weight (BW)], medium (100?mg/kg BW) and high (125?mg/kg BW) dose levels of 2,4-D, respectively. The group D goats served as the control. On day?112, goats in the four groups were sacrificed and the testicular and epididymal sperm reserves were determined. Histopathologic changes in the testis of the 2,4-D-exposed and control goats were also assessed. The mean number of spermatozoa in the testes and the various segments of the epididymides decreased significantly (p?<?0.05) in all the treatment groups relative to the control. Combined testicular sperm reserve per millilitre for the treatment groups (group A—19.61?±?2.63?×?108, group B—12.02?±?1.02?×?108 and group C—9.95?±?0.97?×?108) reduced significantly (p?<?0.05) relative to the mean value (23.52?±?4.43?×?108) of the control—group D. The total epididymal sperm reserve per millilitre in the treatment groups (group A—24.25?±?4.19?×?108, group B—17.18?±?2.57?×?108 and group C—17.88?±?2.89?×?108) was also found to be significantly (p?<?0.05) lower than the mean value (40.85?±?11.24?×?108) for the control—group D. This reduction in the testicular and epididymal sperm counts of the 2,4-D-exposed WAD goats in this study suggest disruption in spermatogenic activity, which may lead to low productivity. Variable degrees of circulatory disturbances were observed in the testis sections of 2,4-D-exposed goats.  相似文献   
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This paper presents new data addressing two important controversies in psychiatry: the construct of Minor Depression (MinD) and the efficacy of St. John’s Wort for milder forms of depressive disorders. Data are from a three-arm, 12 week, randomized clinical trial of investigating the efficacy of St. John’s Wort (810 mg/day), citalopram (20 mg/day), or placebo for acute treatment of MinD. Due to a high placebo response on all outcome measures, neither St. John’s Wort nor citalopram separated from placebo on change in depressive symptom severity, quality of life, or well-being. However, systematic assessment of potential adverse effects (AEs) led to three important observations: (1) prior to the administration of study compound, 60% of subjects endorsed items that would be characterized as AEs once study compound was administered, (2) St. John’s Wort and citalopram were each associated with a significant number of new or worsening AEs during treatment, and (3) using a structured interview for identifying AEs at baseline and during treatment is informative. MinD was not responsive to either a conventional antidepressant or a nutraceutical, and both compounds were associated with a notable side effects burden. Other treatment approaches for MinD should be investigated.  相似文献   
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