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91.
Infection of cultured intestinal epithelial cells with severe acute respiratory syndrome coronavirus 总被引:5,自引:0,他引:5
Cinatl J Hoever G Morgenstern B Preiser W Vogel JU Hofmann WK Bauer G Michaelis M Rabenau HF Doerr HW 《Cellular and molecular life sciences : CMLS》2004,61(16):2100-2112
To identify a model for the study of intestinal pathogenesis of severe acute respiratory syndrome (SARS) we tested the sensitivity of six human intestinal epithelial cell lines to infection with SARS coronavirus (SARS-CoV). In permissive cell lines, effects of SARS-CoV on cellular gene expression were analysed using high-density oligonucleotide arrays. Caco-2 and CL-14 cell lines were found to be highly permissive to SARS-CoV, due to the presence of angiotensin-converting enzyme 2 as a functional receptor. In both cell lines, SARS-CoV infection deregulated expression of cellular genes which may be important for the intestinal pathogenesis of SARS.Received 23 May 2004; received after revision 23 June 2004; accepted 25 June 2004 相似文献
92.
Photoinduced electron transfer is an essential step in the conversion of solar energy into chemical energy in photosystems I and II (ref. 1), and is also frequently used by chemists to build complex molecules from simple precursors. During this process, light absorption generates molecules in excited electronic states that are susceptible to accepting or donating electrons. But although the excited states are straightforward to generate, their short lifetimes makes it challenging to control electron transfer and subsequent product formation-particularly if enantiopure products are desired. Control strategies developed so far use hydrogen bonding, to embed photochemical substrates in chiral environments and to render photochemical reactions enantioselective through the use of rigid chiral complexing agents. To go beyond such stoichiometric chiral information transmission, catalytic turnover is required. Here we present a catalytic photoinduced electron transfer reaction that proceeds with considerable turnover and high enantioselectivity. By using an electron accepting chiral organocatalyst that enforces a chiral environment on the substrate through hydrogen bonding, we obtain the product in significant enantiomeric excess (up to 70%) and in yields reaching 64%. This performance suggests that photochemical routes to chiral compounds may find use in general asymmetric synthesis. 相似文献
93.
Global riverine discharge of organic matter represents a substantial source of terrestrial dissolved and particulate organic carbon to the oceans. This input from rivers is, by itself, more than large enough to account for the apparent steady-state replacement times of 4,00-6,000 yr for oceanic dissolved organic carbon. But paradoxically, terrestrial organic matter, derived from land plants, is not detected in seawater and sediments in quantities that correspond to its inputs. Here we present natural 14C and 13C data from four rivers that discharge to the western North Atlantic Ocean and find that these rivers are sources of old (14C-depleted) and young (14C-enriched) terrestrial dissolved organic carbon, and of predominantly old terrestrial particulate organic carbon. These findings contrast with limited earlier data that suggested terrestrial organic matter transported by rivers might be generally enriched in 14C from nuclear testing, and hence newly produced. We also find that much of the young dissolved organic carbon can be selectively degraded over the residence times of river and coastal waters, leaving an even older and more refractory component for oceanic export. Thus, pre-ageing and degradation may alter significantly the structure, distributions and quantities of terrestrial organic matter before its delivery to the oceans. 相似文献
94.
Zusammenfassung Es wird die muskellähmende Wirkung von Papaverin auf die depolarisierte Taenia coli durch die Blockade des Kalziumionenstromes durch die Zellmembran erklärt. 相似文献
95.
Zusammenfassung Einbettungsformen aus Silikongummi wurden entwickelt mit dem Ziel, eine einfache, saubere und rasche Einbettung für eine grosse Zahl von Gewebsblöcken zu erreichen. Die Formen sind für Epon, Epon-Araldit und Maraglas, aber nicht für Vestopal verwendbar. 相似文献
96.
97.
98.
J. Copeland K. Blashfield B. Bauer G. C. Gerritsen L. C. Ginsberg 《Cellular and molecular life sciences : CMLS》1982,38(3):301-302
Summary Plasma hexosamine levels were elevated in lines of diabetic Chinese hamsters when compared to nondiabetics. Plasma protein bound hexoses,a
2 macroglobulin and total lipoprotein levels were not significantly correlated with either animal line or levels of fasting blood glucose.Acknowledgments. For the support which made this project possible, we wish to thank the Michigan Heart Association and The Upjohn Co. 相似文献
99.
C Bauer 《Experientia》1990,46(11-12):1157-1160