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1.
Forty-six children with the nephrotic syndrome whose renal biopsy specimens showed minimal changes and whose response to corticosteroid therapy was unsatisfactory were treated with cyclophosphamide. Three patients were completely steroid-resistant from the outset and the remainder were steroid-dependent. In several patients steroids controlled the condition less effectively with time. Most patients showed signs of steroid toxicity, and growth retardation was striking.A moderate leucopenia was induced with cyclophosphamide, and treatment was maintained for three to four months in the majority of cases. Thirty-eight children (83%) have remained in complete remission off all treatment for periods of 3 to 23 months, 33 after one course of cyclophosphamide and five after a second course. Two other patients who remitted but relapsed later are still on treatment. In only six patients was full remission not obtained, and three of these were steroid-resistant from the start. Two died from pneumonia and adrenal failure and four continued to have proteinuria, though in one an impressive reduction occurred.The results indicate that cyclophosphamide therapy is an effective alternative for nephrotic children with normal glomeruli on light microscopy who develop steroid dependence or resistance, and who exhibit toxic effects of steroid therapy.  相似文献   
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Measurements of N2O emission fluxes from a 3 ha field of winter wheat were measured using eddy covariance and relaxed eddy accumulation continuously over 10 days during April 1994. The measurements averaged fluxes over approximately 105 m2 of the field, which was fertilised with NH4NO3 at a rate of 43 kg N ha-1 at the beginning of the measurements. The emission fluxes became detectable after the first heavy rainfall, which occured 4 days after fertiliser application. Emissions of N2O increased rapidly during the day following the rain to a maximum of 280 ng N m-2s-1 and declined over the following week. During the period of significant emission fluxes, a clear diurnal cycle in N2O emission was observed, with the daytime maximum coinciding with the soil temperature maximum at 12 cm depth. The temperature dependence of the N2O emission was equivalent to an activation energy for N2O production of 108 kJ mol-1. The N2O fluxes measured using relaxed eddy accumulation, averaged over 30 to 270 min, were in agreement with those of the eddy covariance system within 60%. The total emission of N2O over the period of continuous measurement (10 days) was equivalent to about 10 kg N2O-N, or 0.77% of the N fertiliser applied.  相似文献   
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Quantification of the surface-atmosphere exchange of trace gasesis recognized as an essential prerequisite to understandingthe role of the biosphere in the global climate system. Amongthe micrometeorological methods available to measure surface-atmospherefluxes, the aerodynamic gradient, the energy balance/Bowen ratio,the eddy covariance and the eddy accumulation methods are themost widely employed. This brief review describes the theoreticalbackground and the practical applications of these methodologiesand is particularly directed to plant ecophysiologists, ecologistsand botanists who may be interested in scaling biological processesto the canopy level. Key words: Trace gas exchange, biosphere, surface-atmosphere fluxes, aerodynamic gradient, Bowen ratio, eddy covariance, eddy accumulation, micrometeorology  相似文献   
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A scheme for dealing with cases of non-accidental injury in children in the Derby clinical area has been operating since 1971. A stable team of doctors, policemen, and social workers deal with each case. The parents are told at once that battering is suspected, and the police and social services department co-operate closely in establishing the facts, supporting the family, and protecting the child. A psychiatric assessment of the parents may help social workers decide on the long-term care of the child, and the forensic physician is invaluable if the case has to go to court. The team has made three recommendations about prevention and management of these cases: a specialist social service team should be set up to deal with these children and regain the skills and knowledge lost when children''s departments were abolished in 1971; babies should be routinely weighed naked in infant welfare clinics; and juvenile courts should be able to order a psychiatric report on the parents in care proceedings.  相似文献   
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Alan Moncrieff 《CMAJ》1943,48(1):69-70
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Alan Moncrieff 《CMAJ》1944,51(6):582
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