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41.
42.
Schiestl FP Peakall R Mant JG Ibarra F Schulz C Franke S Francke W 《Science (New York, N.Y.)》2003,302(5644):437-438
The "sexually deceptive" orchid Chiloglottis trapeziformis attracts males of its pollinator species, the thynnine wasp Neozeleboria cryptoides, by emitting a unique volatile compound, 2-ethyl-5-propylcyclohexan-1,3-dione, which is also produced by female wasps as a male-attracting sex pheromone. 相似文献
43.
Memories are thought to be due to lasting synaptic modifications in the brain. The search for memory traces has relied predominantly on determining regions that are necessary for the process. However, a more informative approach is to define the smallest sufficient set of brain structures. The rutabaga adenylyl cyclase, an enzyme that is ubiquitously expressed in the Drosophila brain and that mediates synaptic plasticity, is needed exclusively in the Kenyon cells of the mushroom bodies for a component of olfactory short-term memory. This demonstrates that synaptic plasticity in a small brain region can be sufficient for memory formation. 相似文献
44.
Grueninger D Treiber N Ziegler MO Koetter JW Schulze MS Schulz GE 《Science (New York, N.Y.)》2008,319(5860):206-209
The analysis of natural contact interfaces between protein subunits and between proteins has disclosed some general rules governing their association. We have applied these rules to produce a number of novel assemblies, demonstrating that a given protein can be engineered to form contacts at various points of its surface. Symmetry plays an important role because it defines the multiplicity of a designed contact and therefore the number of required mutations. Some of the proteins needed only a single side-chain alteration in order to associate to a higher-order complex. The mobility of the buried side chains has to be taken into account. Four assemblies have been structurally elucidated. Comparisons between the designed contacts and the results will provide useful guidelines for the development of future architectures. 相似文献
45.
A global view of gene activity and alternative splicing by deep sequencing of the human transcriptome 总被引:6,自引:0,他引:6
46.
Hartwig Schulz 《Genetic Resources and Crop Evolution》2004,51(7):795-795
47.
A comprehensive study of the contents and composition of 15 compounds from the group of polycyclic aromatic hydrocarbons in granulodensimetric fractions of soddy-podzolic soils was performed. The specificity of the accumulation of these substances in the clay (heavy-weight) and light-weight soil fractions was investigated. The levels of the soil contamination in Moscow parks with polyarenes were determined, and the assessment of changes in the degree of the soil contamination over a long period of time was made. 相似文献
48.
Dabrowski J. M. Peall S. K. C. Reinecke A. J. Liess M. Schulz R. 《Water, air, and soil pollution》2002,135(1-4):265-283
The characterization of runoff-related pesticide input and the identification of areas of concern in the field are essential for a comprehensive assessment of risk and the planning of mitigation measures. To this end, the agriculturally-derived aqueous and particle-associated pesticide contamination of the Lourens River and its tributaries was measured in a comprehensive design. Sampling was performed in the beginning of April prior to the first rainfall of the wet season and in the middle of April during high water conditions following the first rainfall of 9.6 mm d-1. Pre-runoff samples indicated contamination with endosulfan at levels up to 0.06 μg L-1, while no other pesticides were detectable. Rainfall-induced runoff resulted in an increase in the levels of the pesticides endosulfan, deltamethrin, azinphos-methyl, chlorpyrifos, and procymidone up to levels of 0.35, 1.4, 0.6, 0.19 and 9 μg L-1, respectively in water samples. Endosulfan, azinphos-methyl, and chlorpyrifos were detected at maximum concentrations of 273, 152, and 245 μg kg-1 in suspended sediments. No increased pesticide levels were detected at a control site upstream of the agricultural area. The Lourens River received its contamination via the tributaries discharging the surrounding farming area. Contamination of the six tributaries depended on landuse and slope characteristics and enabled the identification of target sites for risk reduction approaches. Transient pesticide levels exceeded the target water quality limit proposed by the South African Department of Water Affairs and Forestry (DWAF). The Lourens River site downstream of the farming area has been identified as a site where potential toxic conditions could arise. 相似文献
49.
Seven organophosphate and carbanate insecticides were tested for their effects on C2H2-reduction by alfalfa (Medicago sativa L.), sweetclovcr (Melilotus alba L.) and red clover (Trifolium pratense L.). Plants were grown in vitro for 21 days on nonstcrile vermiculite or soil substrates. Oftanol® was inhibitory to most plants on both soil and vermiculite. Carbofuran's inhibitory effect was almost entirely limited to soil-grown plants. Carbaryl, aldicarb, chlorpyrifos, and terbufos were inhibitory to certain plants under some conditions. Phosmet was the least toxic. Significant differences were observed in toxicity which were dependent on the growth substrate used. The effects of carbamates tended to be restricted to plants grown on soil substrates rather than on vermiculite. Loss of C2H2-reducing ability was usually correlated with inhibition of nodule formation. The insecticides did not inhibit growth of Rhizobium meliloti or R. trifolii in broth culture. 相似文献
50.