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351.
The study has been carried out on male Wistar rats. The aim of the present study was to trace the effect of aluminium chloride and aluminium nitrate at concentration 10 microM and 20 microM on haem biosynthesis in vitro in bone marrow cell culture. The ability of haem biosynthesis in bone marrow cell culture after 48 h of experiments with aluminium chloride and aluminium nitrate significantly decreased in relation with the control value.  相似文献   
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Agrotis segetum Schiff granulosis virus (AsGV) propagated in Denmark was supplied against naturally occurring cutworm populations (A. ipsilon and to a less extentA. segetum) in experimental field plots of tobacco, okra, potato and sugar beet in northern Pakistan. AsGV doses varied between 4 × 107 and 4 × 1011 capsules per m2 plot, and no. of applications between 1 and 3. One treatment with AsGV did not reduce cutworm damage significantly to tobacco seedlings and potato plants. Two treatments with AsGV reduced cutworm damage significantly. In tobacco, reduction was 64–82%, in okra and potato 85% and 77% respectively. Damage in sugar beet was reduced 78%. Three treatments with AsGV dis not reduce damage significantly better than two treatments. AsGV and the chemical insecticides Tamaran and Dieldrin, andBacillus thuringiensis (Thuricide) were about equally effective, reducing damage by 85%, 79%, 87% and 69%, respectively. No difference was found between the efficiency of highly purified AsGV to which activated charcoal was added and partially purified AsGV without charcoal.   相似文献   
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Without fertilization, harvest of perennial bioenergy cropping systems diminishes soil nutrient stocks, yet the time course of nutrient drawdown has not often been investigated. We analyzed phosphorus (P) inputs (fertilization and atmospheric deposition) and outputs (harvest and leaching losses) over 7 years in three representative biomass crops—switchgrass (Panicum virgatum L.), miscanthus (Miscanthus × giganteus) and hybrid poplar trees (Populus nigra × P. maximowiczii)—as well as in no-till corn (maize; Zea mays L.) for comparison, all planted on former cropland in SW Michigan, USA. Only corn received P fertilizer. Corn (grain and stover), switchgrass, and miscanthus were harvested annually, while poplar was harvested after 6 years. Soil test P (STP; Bray-1 method) was measured in the upper 25 cm of soil annually. Harvest P removal was calculated from tissue P concentration and harvest yield (or annual woody biomass accrual in poplar). Leaching was estimated as total dissolved P concentration in soil solutions sampled beneath the rooting depth (1.25 m), combined with hydrological modeling. Fertilization and harvest were by far the dominant P budget terms for corn, and harvest P removal dominated the P budgets in switchgrass, miscanthus, and poplar, while atmospheric deposition and leaching losses were comparatively insignificant. Because of significant P removal by harvest, the P balances of switchgrass, miscanthus, and poplar were negative and corresponded with decreasing STP, whereas P fertilization compensated for the harvest P removal in corn, resulting in a positive P balance. Results indicate that perennial crop harvest without P fertilization removed legacy P from soils, and continued harvest will soon draw P down to limiting levels, even in soils once heavily P-fertilized. Widespread cultivation of bioenergy crops may, therefore, alter P balances in agricultural landscapes, eventually requiring P fertilization, which could be supplied by P recovery from harvested biomass.  相似文献   
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