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Fortification of salt with iron has been suggested as a practical method of iron supplementation. In an effort to identify a suitable method for fortifying salt with iron two approaches were investigated. In one the possibility of fortifying salt with ferrous sulfate and a stabilizing agent was tried. Of the several stabilizing agents studied orthophosphoric acid was found to be the most promising one. Salt fortified with ferrous sulfate and orthophosphoric acid was found to keep well on storage without color development. Bioavailability of iron from this fortified salt, although satisfactory at the beginning, deteriorated on storage. An alternative approach in which salt was fortified with ferric orthophosphate, a stable iron compound and an absorption promoter like sodium acid sulfate was found to be more satisfactory. Salt fortified with ferric orthophosphate (3,500 ppm) and sodium acid sulfate (5,000 ppm) kept well without any color development for several months. The bioavailability of iron from this formula was comparable to that from ferrous sulfate and bioavailability did not decrease even after storage for 4-5 months. This fortified salt was also acceptable. This formula offers a practical solution to fortification of salt with iron. 相似文献
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Gray scale B-scans in renal sinus lipomatosis show a variety of features which must be differentiated from clinically significant pathological processes. Normal kidneys show dense homogeneous central echoes. In renal sinus lipomatosis, however, the central echoes are divided and become more sparse (Type I), interspersed with small relatively echo-free areas (Type II), or outline a single relatively echo-free area resembling a mass (Type III). In contrast to similar features in hydronephrosis or multiple cysts, the relatively echo-free areas in lipomatosis are ill-defined and do present several weak internal echoes. 相似文献
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There are immediate concerns with current commercial ligands that are used for heavy metal precipitation, especially the limited arrays of bonding sites. Previous research has indicated that not only do commercial reagents lack sufficient bonding criteria, but they also fail to provide long-term stability as ligand-metal complexes. For this reason, we have developed a pyridine-based thiol ligand (DTPY) which not only offers multiple bonding sites for heavy metals but also should form stable metal-ligand precipitates. In this study, we used the divalent metals cadmium and copper to model the reactivity and pH stability of divalent metal complexes with the DTPY ligand. Using inductively-coupled plasma spectrometry (ICP), results indicate that a 50.00ppm (parts per million) copper solution, pH of 4.5, can be reduced to below the ICP detection limits of 0.00093ppm (>99.99% removal), and a 50.00ppm cadmium solution, pH of 6.0, can be reduced to 0.06ppm (99.88%). 相似文献
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Irreversible precipitation of mercury and lead 总被引:3,自引:0,他引:3
There are immediate concerns with current commercial reagents that are used for heavy metal precipitation; in particular the fact that the reagents are not specifically designed to bind the targeted metals. The current literature reveals that not only do commercial reagents lack sufficient ability to strongly bind the metals, but they also fail to provide long-term stability as ligand-metal complexes under a variety of moderate conditions. For this reason a new ligand was designed and synthesized: 1,3-benzenediamidoethanethiol (BDETH2). It offers multiple, concerted, bonding sites for heavy metals and forms a stable metal-ligand precipitate. In this study, the formation of compounds comprised of this ligand with the divalent metals, lead and mercury, was explored and the pH stability of the water insoluble precipitates was determined. The leaching properties of the metal-ligand precipitates were determined using inductively coupled plasma (ICP) spectroscopy and cold vapor atomic fluorescence spectroscopy (CVAF). The results indicate that a 50.00 ppm lead solution at a pH of 4.0 may be reduced to a concentration of 0.05 ppm (99.9% lead removal) and to 0.13 ppm (99.7% lead removal) at a pH 6.0. A 50.00 ppm mercury solution at pH 4.0 may be reduced to a concentration of 0.02 ppm (99.97% mercury removal) and to 0.02 ppm (99.97% mercury removal) at a pH of 6.0. 相似文献
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OBJECTIVE: The authors examined the efficacy of intramuscular flunitrazepam compared with intramuscular haloperidol for the immediate control of agitated or aggressive behavior in acutely psychotic patients. METHOD: Twenty-eight actively psychotic inpatients, aged 20-60 years, who were under treatment with neuroleptic agents were selected for the study. Each was randomly assigned on a double-blind basis to receive either 5 mg i.m. of haloperidol (N=13) or 1 mg i.m. of flunitrazepam (N=15) during an aggressive event. Verbal and physical aggression was measured over time with the Overt Aggression Scale. Patients were also rated with the Brief Psychiatric Rating Scale and the Clinical Global Impression scale. RESULTS: Both flunitrazepam and haloperidol exhibited acute antiaggressive activity. This beneficial effect, as assessed by the Overt Aggression Scale, was obtained within 30 minutes. CONCLUSIONS: Intramuscular flunitrazepam may serve as a convenient, rapid, safe, and effective adjunct to neuroleptics in reducing aggressive behavior in emergency psychiatric settings. 相似文献
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PURPOSE: To evaluate the efficacy of topical mitomycin C in treating conjunctival and corneal epithelial dysplasia and neoplasia. METHODS: Seven eyes of seven patients with conjunctival and corneal epithelial dysplasia and neoplasia were treated with one drop of topical mitomycin C 0.04% four times a day for 7 days in alternate weeks. The patients' charts were reviewed retrospectively. Patients with either multiple recurrences or extensive ocular surface involvement were treated. In all eyes, the diagnosis of epithelial dysplasia or neoplasia was confirmed by histopathology before the onset of therapy. Patients were examined at least every 14 days during treatment and examined at intervals after completion of treatment. RESULTS: With topical mitomycin C, six eyes of seven patients had complete clinical regression of their conjunctival and corneal epithelial dysplasia and neoplasia. One eye of one patient had partial clinical regression of conjunctival and corneal epithelial dysplasia. Follow-up after completion of topical mitomycin C therapy and excision of residual disease ranged from 2 to 16 months (mean, 9 months; SD, 4.3 months) and was without clinical sign of recurrence. Topical mitomycin C therapy was associated with transitory ocular discomfort, conjunctival injection, tearing, photophobia, and punctate epithelial keratopathy. CONCLUSION: In this small series of eyes, topical mitomycin C was effective as a treatment for conjunctival and corneal epithelial dysplasia and neoplasia. 相似文献
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