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581.
582.
Under conditions of the spontaneous or induced autolysis of thick cell suspensions,Arthrobacter globiformis strains produced cells exhibiting features typical of resting microbial forms. The number of viable resting cells was greater
under conditions of induced rather than spontaneous autolysis. The thermoresistance of the resting cells of A.globiformis strains isolated from 2-to 3 million-year-old permafrost was higher than that of the collectionA. globiformis strain. 相似文献
583.
Ascocarps of the hypogaean fungus Elaphomyces spp. from some Swedish forest stands were examined for production of ethylene. Significant amounts were produced by mature ascocarps of E. asperulus and E. granulatus. E. muricatus, which was found only in juvenile or immature stages, did not produce ethylene. None of the ascocarps studied were infected by Cordyceps. The ecological role of the ethylene production by the ascocarps is shortly discussed. 相似文献
584.
585.
Die Autorinnen legen drei neuen Fachausdrücke für die an Samen der FamilieFabaceae festgestellten Gebilde for. Macula cicatricularis—ein Makel um die Narbe (cicatricula), macula raphalis—ein Makel um die Sammennaht (raphe), und fissum hilare—eine linienförmige Vertiefung inmitten des Nabels (hilum). 相似文献
586.
587.
Thyroid hormone regulation of apoptotic tissue remodeling during anuran metamorphosis 总被引:1,自引:0,他引:1
ShiYB FuLI 《Cell research》2001,11(4):245-252
588.
G. Schaefer Uwe Faust Vizeprsident Josef W. Lengeler H.- J. Koch Gertrud Dudin-Gross Hans Mohr B. Sakmann E. Neher E. O. Fischer H. Michel Elisabeth von Falkenhausen Hans Dieter Frey L. Horst Grimme Antje Meyer-Berge Wolfgang Haupt Albrecht E. Sippel Angelika Mette Alfred Pühler Horst Bayrhuber 《当今生物学》1993,23(4):49-63
589.
Limiting effect of abioseston on food ingestion, postembryonic development time and fecundity of daphnids in Lake Balaton (Hungary) 总被引:2,自引:0,他引:2
During ice-free periods, seston ranges from 10 to 600 and averages29.2 mg dry wt 11 in Lake Balaton, the largest shallowlake in Central Europe. Most (8099%) of the seston consistsof 110 µm sized mineral particles. The abiosestoncauses permanent food limitation in the ingestion of the ediblephytoplankton (122 µm fraction) by Daphnia cucullataand D.galeata. The postembryonic development time of D.galeataincreases and its fecundity decreases with increasing abioseston.The fecundity and the mortality of D.galeata are balanced atan abioseston concentration of 20.0 mg dry wt 11. 相似文献
590.
Laima Blažytė-Čereškienė Vincas Būda Edita Bagdonaitė 《Plant Systematics and Evolution》2012,298(4):819-826
The European wild strawberry species Fragaria vesca L., Fragaria viridis Weston, and Fragaria moschata Weston are sympatric and bloom concurrently, introducing the possibilities of cooperation and competition for pollinators.
We studied the pollination biology of strawberries that were grown in rectangular plots at a field site near Vilnius city
in Lithuania. The number of open flowers, the number of insects visiting flowers, and the plot area covered by strawberry
plants were recorded. Wild strawberries were visited by solitary bees (38.5%), flies (31.4%), and other hymenopterans (21%;
ants accounted for approximately 98% of this group). Coleopterans, lepidopterans and honey bees together represented less
than 10% of the insects recorded on strawberries. Fragaria viridis and F. moschata flowers were more attractive to pollinators than those of F. vesca. The main visitors of F. viridis were small solitary bees; those of F. moschata were ants, while F. vesca flowers were visited by solitary bees, ants and flies in comparable numbers. We discuss competition for pollinators and the
possible impact of climate fluctuation on strawberry-pollinator interactions. 相似文献