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231.
We estimated the variability among nations in the prevalence of stunting and wasting, evaluated which national factors are associated with stunting and wasting and examined the relationship of stunting with wasting. The World Health Organization Global Database on Child Growth, a comprehensive conceptual model and a database of national factors were used with variance components and regression analyses. There was substantial variability among nations and among provinces within nations. Most national variability for stunting (76%) and wasting (66%) was explained by national factors and geographic region. Higher energy availability, female literacy and gross product were the most important factors associated with lower prevalence of stunting. The association of health expenditures and stunting differed by region. Higher immunization rate and, for Asia only, energy availability were the most important factors associated with lower prevalence of wasting. Regional differences in the relationship between stunting and wasting were accounted for by national factors. Some factors associated with stunting and wasting differ at the national level. Child malnutrition within a household is greatly influenced by issues at national and provincial levels, and intervention should be considered at all three levels. 相似文献
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BR Branchini RA Magyar KM Marcantonio KJ Newberry JG Stroh LK Hinz MH Murtiashaw 《Canadian Metallurgical Quarterly》1997,272(31):19359-19364
Firefly luciferase catalyzes the highly efficient emission of yellow-green light from substrate luciferin by a series of reactions that require MgATP and molecular oxygen. We prepared 2-(4-benzoylphenyl)thiazole-4-carboxylic acid (BPTC), a novel benzophenone-based substrate analog, intending to use it in photoaffinity labeling studies to probe the luciferase active site. Instead, we found that while BPTC was a potent photoinactivating reagent for firefly luciferase, it was not a photoaffinity labeling agent. Using proteolysis, reverse phase high-performance liquid chromatography, tandem high performance liquid chromatography-electrospray ionization mass spectrometry, and Edman sequencing, we identified a single luciferase peptide, 244HHGF247, the degradation of which was directly correlated to luciferase photoinactivation. Results of enzyme kinetics and related studies were consistent with this peptide being at or near the luciferin binding site. Further, peptide model studies and additional investigations on the nature of the photoinactivation process strongly suggested that BPTC catalyzed the formation of singlet oxygen at the active site of the enzyme. We describe here an uncommon example of active site-directed photooxidation of an enzyme by singlet oxygen. 相似文献
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ET Creagan KM Rowland VJ Suman CG Kardinal RF Marschke RS Marks WJ Maples 《Canadian Metallurgical Quarterly》1997,20(5):490-492
Adoptive immunotherapy (AI) with interleukin-2 (IL-2) and lymphokine-activated killer cells (LAK) is an antineoplastic modality in which immune-activated cells are administered to a host with advanced cancer in an attempt to mediate tumor regression. Levamisole (LEV), an immune stimulant, has been suggested to have therapeutic effectiveness in a variety of cancers. After a phase I trial of recombinant IL-2 plus LEV, a phase II trial of this combination was conducted in patients with advanced malignant melanoma. Nineteen patients were entered in the trial. They received IL-2 at 3 x 10(6) U/m2 subcutaneously daily x 5 plus LEV 50 mg/ m2 orally three times daily (p.o. t.i.d.) x 5. Patients were reevaluated at four-week intervals. None of the patients achieved a partial or complete regression (PR, CR). The median time to treatment failure (refusal, progression, or off study due to toxicity) was 56 days. Grade IV toxicities included vomiting (3 patients), lethargy (1 patient), and musculoskellar pain (1 patient). This regimen is not recommended for further testing in patients with advanced malignant melanoma. 相似文献
236.
Arnett Peter A.; Rao Stephen M.; Grafman Jordan; Bernardin Linda; Luchetta Tracey; Binder Jeffrey R.; Lobeck Lorri 《Canadian Metallurgical Quarterly》1997,11(4):535
Previous studies have consistently demonstrated impairments in conceptual reasoning and set-shifting abilities in patients with multiple sclerosis (MS). Other executive functions have been less frequently examined. We compared 44 MS patients and 48 demographically matched controls on a temporal-ordering and semantic-encoding task and on a test of planning (Tower of Hanoi). Compared with controls, MS patients experienced deficient semantic encoding and planning but unimpaired temporal-order memory. For both tasks, post hoc analyses indicated that chronic-progressive MS patients contributed most to the group differences. A combination of poor planning and slowed information-processing speed was hypothesized to have contributed to MS patients' impaired Tower of Hanoi performance. Further research is needed to explore the possible relationship between semantic-encoding and planning deficits in MS and social and occupational disabilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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KM Vollman 《Canadian Metallurgical Quarterly》1997,16(4):184-193
Various strategies have been tested in attempts to improve gas exchange in patients with Acute Respiratory Distress Syndrome (ARDS). However, it appears that the simple non-invasive act of prone positioning of the critically ill ARDS patient may improve gas exchange while preventing potential complications of high positive end expiratory pressure (PEEP), volutrauma, and oxygen toxicity. 相似文献
238.
S Okada H Kita TJ George GJ Gleich KM Leiferman 《Canadian Metallurgical Quarterly》1997,16(4):455-463
BACKGROUND: With improvements in HIV antibody test (ELISA) performance, the window of time between infection and seroconversion becomes a major source of error in HIV screening. The authors examined its impact on the false-reassurance rate (FRR). METHODS: Test sensitivity was modeled as the product of two factors: the inherent sensitivity (sensitivity when antibody is present) and the probability that antibody is present in infected blood. A model of HIV and AIDS incidence was used to derive an estimate of the probability of remaining in the seronegative window (pw) among those who are infected. With plausible assumptions, this probability approaches 0.03. The FRR was then estimated as a function of the probability of remaining in the seronegative window, the prevalence of HIV, and the inherent sensitivity of the ELISA test were estimated. RESULTS: The FRRs for two blood donor groups, one with an HIV prevalence of 0.004 and a typical probability of remaining in the seronegative window (pw = 0.03) and the other with a higher prevalence of 0.017 but fewer donors in the window (pw = 0.003), are equal (140 per million donors) if the blood is negative on a single ELISA test. After two negative tests or a single test that can detect antibody more reliably, however, the FRR is much higher in the group with the higher pw (= 120 per million compared with 50 per million), because the greater numbers of donors in the window more than offsets the lower prevalence. CONCLUSION: With improvements in inherent sensitivity of ELISA by virtue of technical progress or retesting, the prevalence of HIV infection may no longer play the critical role in degrading the results of blood screening. As inherent test performance improves, tests are increasingly likely to miss infected blood because of the seronegative-window error rather than because of measurement error. Window error plays a proportionally greater role during the early stages of HIV dissemination in a population where the incidence of new HIV infection is high relative to the incidence of AIDS. These findings may explain, in part, the recent observation that cases of transfusion of contaminated blood often take place in areas where AIDS epidemics have started recently. They also suggest that the traditional strategy of soliciting blood donors from low-prevalence populations may not always be optimal, unless such populations are truly low-risk. 相似文献
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