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Ferdinand Bohlmann Pahup Singh Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1982,21(2):371-374
An investigation of the aerial parts of Chromolaena chasleae afforded a prostaglandin-like acid, whose structure followed from the 1H NMR spectral data and from the reaction with periodate, which afforded a hemiacetal. From a new Chromolaena species, three novel cadinene derivatives were isolated, which were closely related to those isolated previously from this genus. 相似文献
63.
Weijers D Schlereth A Ehrismann JS Schwank G Kientz M Jürgens G 《Developmental cell》2006,10(2):265-270
The Arabidopsis embryonic root meristem is initiated by the specification of a single cell, the hypophysis. This event critically requires the antagonistic auxin response regulators MONOPTEROS and BODENLOS, but their mechanism of action is unknown. We show that these proteins interact and transiently act in a small subdomain of the proembryo adjacent to the future hypophysis. Here they promote transport of auxin, which then elicits a second response in the hypophysis itself. Our results suggest that hypophysis specification is not the direct result of a primary auxin response but rather depends on cell-to-cell signaling triggered by auxin in adjacent cells. 相似文献
64.
Jacques Danielle Bkaily Ghassan Jasmin Gaétan Ménard Daniel Proschek Libuse 《Molecular and cellular biochemistry》1997,176(1-2):249-256
Using the whole-cell voltage-clamp technique, early embryonic tetrodotoxin (TTX) and Mn2+-insensitive slow Na+ current was detected in 10-22 week old fetal human heart cells as well as in 1-day-old and young cardiomyopathic hamster myocytes. This slow Na+ current in both heart cell preparations has the same kinetics and pharmacology. This type of slow Na+ current was absent in heart cells of newborn and young normal hamsters and became less present in myocytes of 19 and 22 week old human heart myocytes. Our results demonstrate that the slow Na+ channel does exist in early fetal human life and this type of channel continues to be functional after birth in myocytes of the hereditary cardiomyopathic hamster. 相似文献
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Impaired pulmonary host defense in mice lacking expression of the CXC chemokine lungkine 总被引:5,自引:0,他引:5
Chen SC Mehrad B Deng JC Vassileva G Manfra DJ Cook DN Wiekowski MT Zlotnik A Standiford TJ Lira SA 《Journal of immunology (Baltimore, Md. : 1950)》2001,166(5):3362-3368
Lungkine (CXCL15) is a novel CXC chemokine that is highly expressed in the adult mouse lung. To determine the biologic function of Lungkine, we generated Lungkine null mice by targeted gene disruption. These mice did not differ from wild-type mice in their hematocrits or in the relative number of cells in leukocyte populations of peripheral blood or other tissues, including lung and bone marrow. However, Lungkine null mice were more susceptible to Klebsiella pneumonia infection, with a decreased survival and increased lung bacterial burden compared with infected wild-type mice. Histologic analysis of the lung and assessment of leukocytes in the bronchioalveolar lavage revealed that neutrophil numbers were normal in the lung parenchyma, but reduced in the airspace. The production of other neutrophil chemoattractants in the Lungkine null mice did not differ from that in wild-type mice, and neutrophil migration into other tissues was normal. Taken together, these findings demonstrate that Lungkine is an important mediator of neutrophil migration from the lung parenchyma into the airspace. 相似文献
70.
Uzunova K Vassileva A Kambourova M Ivanova V Spasova D Mandeva R Derekova A Tonkova A 《Zeitschrift für Naturforschung. C, Journal of biosciences》2001,56(11-12):1022-1028
Inulinase and Invertase Activities, Thermophilic Bacilli, Enzyme Thermostability Enzyme production of newly isolated thermophilic inulin-degrading Bacillus sp. 11 strain was studied by batch cultivation in a fermentor. The achieved inulinase and invertase activities after a short growth time (4.25 h) were similar or higher compared to those reported for other mesophilic aerobic or anaerobic thermophilic bacterial producers and yeasts. The investigated enzyme belonged to the exo-type inulinases and splitted-off inulin, sucrose and raffinose. It could be used at temperatures above 65 degrees C and pH range 5.5-7.5. The obtained crude enzyme preparation possessed high thermostability. The residual inulinase and invertase activities were 92-98% after pretreatment at 65 degrees C for 60 min in the presence of substrate inulin. 相似文献