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81.
The effects of arachidonic acid in cerebral blood vessels has been examined using rings of canine cerebral arteries. Arachidonic acid produced dose-dependent contractions of this preparation even after mechanical removal of the endothelium. The contractions were not blocked by indomethacin or acetylsalicylic acid, both of which inhibit cyclooxygenase, but were inhibited by nordihydroguaiaretic acid which is a lipoxygenase inhibitor, BW 755c which blocks both pathways, and FPL 55712 which is an antagonist at leukotriene receptors. These data imply that arachidonic acid-induced contractions are mediated by products of the lipoxygenase pathway. Leukotrienes and cyclooxygenase products are generated by this preparation as shown by HPLC and radioimmunoassay and both LTC4 and LTD4 produce contractions in cerebral arteries lending further evidence in support of this suggestion. 相似文献
82.
Three new isocoumarin derivatives ( 2- 4) were isolated together with monocerin ( 1) from Microdochium bolleyi, an endophytic fungus from Fagonia cretica, a herbaceous plant of the semiarid coastal regions of Gomera. Compounds 2 and 3 are both 12-oxo epimers of 1, and 4 is a ring-opened derivative of 1. The structures were elucidated by detailed spectroscopic analysis and comparison with reported data. The absolute configurations were determined by a modified Mosher's method. Compounds 1, 3, and 4 showed good antifungal, antibacterial, and antialgal activities against Microbotryum violaceum, Escherichia coli, Bacillus megaterium, and Chlorella fusca. Compound 2 was moderately antifungal and antialgal. 相似文献
83.
A R Johnson W W Schulz L A Noguiera E G Erd?s 《Clinical and experimental hypertension》1980,2(3-4):659-674
Human pulmonary endothelial cells were used to study the metabolism of angiotensin I and bradykinin by angiotensin I converting enzyme (kininase II; ACE). The endothelial cells cultured from pulmonary arteries and veins differed with respect to their enzyme activity and their surface structure, as viewed with scanning electron microscopy. Cells from adult pulmonary arteries had greater ACE activity than cells from either adult pulmonary veins or fetal pulmonary arteries. In addition, cells from adult pulmonary arteries exhibited more prominent surface projections than cells from veins or fetal pulmonary arteries. A brief exposure to trypsin decreased the ACE activity in cells from arteries but not in cells from veins. Possible the differences in ACE activity between these cells are related to their surface structures. 相似文献
84.
Zusammenfassung Nach unseren, sich auf ein Diagramm vonHerzberg-Kremmer u.Herzberg beziehenden Berechnungen beträgt die durchschnittliche Dauer der Virämie beim normalen menschlichen Erstimpfling 3 Tage. Der Variationsbereich des erstmaligen Auftretens des Vaccinevirus in der Blutbahn liegt zwischen dem 2. und 8. Tag nach der Impfung. 相似文献
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Pflügers Archiv - European Journal of Physiology - 相似文献
87.
Diagnostic hallmarks and pitfalls in late-onset progressive transthyretin-related amyloid-neuropathy
Maike F. Dohrn Christoph Röcken Jan L. De Bleecker Jean-Jacques Martin Matthias Vorgerd Peter Y. Van den Bergh Andreas Ferbert Katrin Hinderhofer J. Michael Schröder Joachim Weis Jörg B. Schulz Kristl G. Claeys 《Journal of neurology》2013,260(12):3093-3108
Familial amyloid polyneuropathy (FAP) is a progressive systemic autosomal dominant disease caused by pathogenic mutations in the transthyretin (TTR) gene. We studied clinical, electrophysiological, histopathological, and genetic characteristics in 15 (13 late-onset and two early-onset) patients belonging to 14 families with polyneuropathy and mutations in TTR. In comparison, we analysed the features of nine unrelated patients with an idiopathic polyneuropathy, in whom TTR mutations have been excluded. Disease occurrence was familial in 36 % of the patients with TTR-associated polyneuropathy and the late-onset type was observed in 86 % (mean age at onset 65.5 years). Clinically, all late-onset TTR-mutant patients presented with distal weakness, pansensory loss, absence of deep tendon reflexes, and sensorimotor hand involvement. Afferent-ataxic gait was present in 92 % leading to wheelchair dependence in 60 % after a mean duration of 4.6 years. Autonomic involvement was observed in 60 %, and ankle edema in 92 %. The sensorimotor polyneuropathy was from an axonal type in 82 %, demyelinating or mixed type in 9 % each. Compared to the TTR-unmutated idiopathic polyneuropathy patients, we identified rapid progression, early ambulatory loss, and autonomic disturbances, associated with a severe polyneuropathy as red flags for TTR–FAP. In 18 % of the late-onset TTR-FAP patients, no amyloid was found in nerve biopsies. Further diagnostic pitfalls were unspecific electrophysiology, and coincident diabetes mellitus (23 %) or monoclonal gammopathy (7 %). We conclude that a rapid disease course, severely ataxic gait, hand involvement, and autonomic dysfunction are diagnostic hallmarks of late-onset TTR–FAP. Genetic analysis should be performed even when amyloid deposits are lacking or when polyneuropathy-causing comorbidities are concomitant. 相似文献
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Alison J. Peel Claude Kwe Yinda Edward J. Annand Adrienne S. Dale Peggy Eby John-Sebastian Eden Devin N. Jones Maureen K. Kessler Tamika J. Lunn Tim Pearson Jonathan E. Schulz Ina L. Smith Vincent J. Munster Raina K. Plowright Bat One Health Group 《Emerging infectious diseases》2022,28(5):1043
A novel Hendra virus variant, genotype 2, was recently discovered in a horse that died after acute illness and in Pteropus flying fox tissues in Australia. We detected the variant in flying fox urine, the pathway relevant for spillover, supporting an expanded geographic range of Hendra virus risk to horses and humans. 相似文献