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711.
Halac Silvana; Felip Marisol; Camarero Lluis; Sommaruga-Wograth Sabine; Psenner Roland; Jordi Catalan; Sommaruga Ruben 《Journal of plankton research》1997,19(11):1671-1686
The effect of solar UVB radiation on the growth and speciescomposition of phytoplankton from a high-mountain lake (2417m a.s.l.) was studied in situ for 16 days in two enclosuresof 1 m receiving either full sunlight or sunlight without UVB.A total of 20 species were identified in both enclosures, consistingmainly of dinoflagellates, chrysophytes and diatoms. Duringthe experiment, there were no significant differences in phytoplanktonspecies composition between the two enclos ures. In both treatments,the abundance of phytoplankton increased continuously, and chlorophylla changed by -5-fold. We observed high fluctuations in the abundanceof several species. However, these fluctuations occurred inboth enclosures, and hence they were not related to UVB radiation.Some species were affected by daily fluctuations of radiation(UVA + photosynthetically active radi ation). Cyclotella aff.gordonensis showed a robust positive correlation, whereas speciesof Gymno dinium were negatively correlated. For most species,the sensitivity to radiation found during the experiment wasconsistent with their diurnal vertical distribution in the lake.Our findings suggest that the phytoplankton from this very clearlake (10% of the surface UVB radiation at 305 nm reached 9.6m depth) were well adapted to the high UVB radiation charactensticof high-elevation sites. 相似文献
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Miguel A. Izquierdo George L. Scheffer Anouk B. Schroeijers Mariska C. de Jong Rik J. Scheper 《Cytotechnology》1998,27(1-3):137-148
In this review we analyze the data supporting the notion that vault-related MDR, as reflected by LRP/MVP overexpression, represents
a marker of drug resistance in vitro and in the clinic. Vaults, besides playing a fundamental biological role, may be involved
in a novel mechanism of MDR.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献