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71.
Bog phosphates of Western Siberia were characterized; the agrochemical properties of vivianite in peat deposits were studied, and its positive effect on the phosphate pool of zonal soils was revealed. A high and prolonged effect of peat vivianite on the main agricultural crops was experimentally proved. It was shown that the wide use of bog phosphates as fertilizers offers much promise for the regional agriculture.  相似文献   
72.
We exploited the exceptional thermal stability and diverse molecular shapes of higher diamondoids (C22 and higher polymantanes) to isolate them from petroleum. Molecules containing 4 to 11 diamond-crystal cages were isolated and crystallized, and we obtained single-crystal x-ray structures for representatives from three families. Rigidity, strength, remarkable assortments of three- dimensional shapes, including resolvable chiral forms, and multiple, readily derivatizable attachment sites make them valuable nanometer-size molecular building blocks.  相似文献   
73.
Rodenticides.   总被引:1,自引:0,他引:1  
Rodenticides are second only to insecticides in the prevalence of pesticide exposure. Hundreds of rodenticide products currently exist, yet only a handful of them are involved in most toxicoses of companion animals. The most commonly reported toxicoses in the United States are those caused by anticoagulant rodenticides, bromethalin, cholecalciferol, strychnine, and zinc phosphide. The pathophysiologic findings, diagnosis, and treatment of each of these five rodenticides are discussed.  相似文献   
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Using the inoculation of both the intact plants of Triticum L. and leaf segments of the plant in the presence of kinetin with the complex population of Puccinia triticina Erikss, the genotype-dependent induction of resistance by kinetin was found. It was proved that this induction depends on the concrete gene of resistance of the plant and on the genotype of pathogen.  相似文献   
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Preliminary results from the rearward-looking electrostatic analyzer of the plasma science experiment during the Mariner 10 encounter with Venus are described. They show that the solar-wind interaction with the planet probably involves a bow shock rather than an extended exosphere, but that this is not a thin boundary at the point where it was crossed by Mariner 10. An observed reduction in the flux of electrons with energies greater than 100 electron volts is interpreted as evidence for somne direct interaction with the exosphere. Unusual intermittent features observed downstream of the planet indicate the presence of a comet-like tail hundreds of scale lengths in length.  相似文献   
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Quantitative autoradiography of [3H]muscimol binding in rat brain   总被引:3,自引:0,他引:3  
A simple quantitative autoradiographic technique for the study of neurotransmitter receptors that includes the use of a tritium-sensitive film permits saturation, kinetic, and competition studies of brain samples as small as 0.01 cubic millimeter. This technique was used to study [3H]muscimol binding in rat brain. Unilateral gamma-aminobutyric acid receptor supersensitivity was observed in the substantia nigra pars reticulata after production of localized lesions of the ipsilateral corpus striatum.  相似文献   
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