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991.
The persistence and retention of active ingredients in granules of Thimet 15G (phorate 15% by weight), Dyfonate 10G (fonofos 10% by weight), Counter 15G (terbufos 15% by weight), and Furadan 10G (carbofuran 10% by weight) were determined in silt loam and organic muck agricultural soils typical of the lower Fraser River valley (BC, Canada). In June 1995, treatment bags made of polyester cloth (7.5 x 7.5 cm) containing granules of a single insecticide, either alone or with soil, were placed during spring planting in the bottom of the furrow and retrieved periodically until April 1996. The parent component of each insecticide declined monotonically except for carbofuran (logistic decline). In the silt loam (organic muck) soil, the average June-to-October first-order rate constants and half-lives were 0.009 (0.010)/d and 80 (71) d for fonofos, 0.012 (0.009)/d and 58 (82) d for phorate, and 0.032 (0.015)/d and 21 (47) d for terbufos; the half-life of carbofuran was 129 (97) d. By December, the average amounts of fonofos and phorate in silt loam (organic muck) were 26% (range: 17-40%; 14% [range: 3.4-21%]) and 21% (range: 15-30%; 10% [range: 5.0-24%]) of the initial amounts of active ingredients measured at time zero, respectively. By April, the percentages dropped to 16% (range: 7.8-24%; 2.3% [range: 0-7.7%]) and 7.3% (range: 1.9-25%; 0.6% [range: 0-1.9%]). During this period, about 95% of the active ingredients were granule bound, the rest remaining in the bag. Only low levels of terbufos and carbofuran persisted in both soils from December to April of the following year. Results indicate an enhanced probability for poisoning of waterfowl and raptors because of the high levels of active ingredients retained on granules of all four insecticides in both soils in the fall. The risk of acute poisoning by phorate and fonofos continued though the winter.  相似文献   
992.
First-line pharmacotherapy for tobacco use and dependence   总被引:1,自引:0,他引:1  
First-line pharmacotherapies for tobacco use and dependence (namely, nicotine patch, nicotine gum, nicotine inhaler, nicotine nasal spray, and sustained-release bupropion) are safe and have been empirically determined to be efficacious and should always be considered part of a tobacco treatment intervention program unless contraindicated. Studies published subsequent to the literature synthesized in TTUD support previously determined efficacy of first-line pharmacologic medications for treatment of tobacco use and dependence. Further studies will be necessary to define clearly the efficacy and relative safety of combination treatments.  相似文献   
993.
A 22-month-old girl with cystinotic rickets was given 1 microgram 1,25-dihydroxycholecalciferol (1,25-DHCC) daily in addition to standard treatment. Her rickets healed and linear growth rate appeared to increase. It is suggested that the effect of 1,25-DHCC and its metabolically active analogues on cystinotic rickets should be further studied.  相似文献   
994.
Scintiscans of liver and spleen using technetium 99m sulphur colloid in 15 infants with extrahepatic biliary atresia and 11 infants with severe obstructive jaundice (7 with genetic deficiency of alpha 1-antitrypsin) showed similar hepatic size, pattern of isotope uptake, and splenic abnormality with no distinguishing features. In 37 older children with a variety of liver disorders, the scan was invaluable in showing filling defects in five instances. Selenomethionine was taken up not only by the two filling defects due to hepatoblastoma but also in a haemangioendothelioma. In the remaining patiens liver scanning confirmed hepatic abnormality and the necessity for more specific invasive diagnostic investigations.  相似文献   
995.
A clinical and biochemical evaluation has been made of a new milk formula, Modified Carnation milk (MCM), based on cows'' milk but with the mineral content and concentration of caloric nutrients altered to make it correspond more closely to human milk. MCM produced higher plasma calcium and magnesium concentrations in 6-day-old infants than those produced by unmodified evaporated and dried milks, achieving concentrations closer to those of breast milk. Plasma free amino acid concentrations in MCM-fed infants are nearer breast-fed values than those in unmodified milk-fed infants where higher individual plasma amino acid concentrations persist during the first 3 months. MCM-fed infants had low plasma urea concentrations and lower urine osmolalities at 6 days, 3 weeks, 6 weeks, 3 months, and 6 months than infants fed on the evaporated and dried milks, and similar plasma urea and urine osmolalities to those of breast-fed infants. MCM is likely to be superior to unmodified evaporated and dried milks in preventing convulsions of the hypocalcaemic/hypomagnesaemic/hyperphosphataemic type, and seems less likely to cause hypertonic dehydration. MCM is easily prepared, readily accepted by babies, and appears to be nutritionally adequate for the feeding of term infants.  相似文献   
996.
Primary care trust commissioning is not advanced and there is little evidence of PCTs influencing hospital services. Any further NHS reorganisation would hamper the development of commissioning. PCTs need to engage more GPs in the task of commissioning services. PCTs' ability to move work round on a cost per case basis should strengthen their hand in commissioning from hospitals.  相似文献   
997.
Photographs, drawings, and examination at consultation have value in rhinoplastic planning. However, the surgeon is not operating on photographs, drawings, or an alert sitting or standing patient; he is operating on a nose with what was forward now facing upward. We find it most helpful to plan and mark almost the entire procedure on the external nose and surrounding structures just before the patient is put supine and sedated or anesthetized. In primary rhinoplasty, it is possible to mark essentially all skeletal anatomy within 1 mm tolerances by palpation, pushing the tip up and back, observing the changes from the outside, and looking at the inside. We believe that the anatomy and planned changes can and should be depicted by appropriate marks put on the skin. The mere act of drawing in the procedure forces us to think it through from beginning to end, a most worthwhile endeavor. Moreover, we learned very shortly after we began forcing ourselves to quantitate the anatomy and proposed changes, that we ran into fewer and fewer surprises as we worked. Photographs taken of the markings become by far the best “operative note” we can have. Comparison of these with the patient or his photographs showing the result allow us to make accurate judgments about long term effects of each surgical maneuver. Much that seemed mysterious before is found to be quite scientifically explainable. We do not propose in this short report to show how we mark every nose. Rather we shall show with drawings and a few examples how we go about marking a nose. The reader may use the suggested marking techniques or may evolve his own. The important thing is that he work out a system meaningful to him. It will be noted that we have used differing techniques for depicting similar concepts from case to case. In other words, we have not settled immutably on one system because we are still searching for the best.  相似文献   
998.
999.
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1000.
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