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81.
82.
Anaemia is a commonly encountered medical condition, although associated ophthalmic manifestations are not often sought or recognised. The authors present a case report of a patient with severe vitamin B12 deficiency anaemia with florid retinal changes classical of anaemic retinopathy. A review of the ocular involvement in anaemia is also presented. 相似文献
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BA Stankiewicz PF Van Bergen IJ Duncan JF Carter DE Briggs RP Evershed 《Canadian Metallurgical Quarterly》1996,10(14):1747-1757
Flash pyrolysis/gas chromatography (py/GC) and py/GC/mass spectrometry (MS) have been utilized to characterize the cuticles of invertebrates chemically. Pyrolysis products have been identified and assigned to specific cuticular components. Acetylpyridones, acetamidofuran, 3-acetamido-5-methylfuran and 3-acetamido-(2 and 4)-pyrones are proposed as characteristic pyrolysis markers for chitin. Pyrolysis products displaying ions of m/z 70, 154, 168, 194 are thought to derive from diketopiperazine structures and provide potential markers for proteins and peptides in which proline, alanine, valine, arginine and glycine are the dominant amino acids. These products, constituting specific pyrolysis markers for invertebrate cuticles, may reflect the amino acid composition of their constituent structural proteins. The source of the various pyrolysis products of proteins has been verified by pyrolysis of reference proteins, peptides and amino acid mixtures. The presence of additional pyrolysis products related directly to histidine and catechol moieties is consistent with the chemical structure and composition proposed for arthropod cuticles based on recent work utilizing solid state 13C and 15N nuclear magnetic resonance. This study constitutes the first comprehensive chemical characterization of the pyrolysis products of invertebrate cuticles and provides the basis for future investigations requiring qualitative screening for cross-linked chitin and proteins in modern and fossil cuticles and in materials, e.g. geopolymers, that may be derived from them. 相似文献
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LL Lindley BM Reininger ML Vincent DL Richter RP Saunders L Shi 《Canadian Metallurgical Quarterly》1998,68(5):205-212
A random-digit dialed telephone survey was conducted in a traditionally conservative southern state to determine the level of support for sexuality education in the public schools including support for specific sexuality education topics, the earliest grade level at which each topic should be taught, and the amount of instruction time required for sexuality education in the high schools. Survey data were obtained from 534 South Carolina registered voters in late January/early February 1997. Results demonstrated that most South Carolina registered voters: 1) supported sexuality education in the public schools; 2) supported instruction on a variety of sexuality education topics; 3) supported instruction at all grade levels, especially beginning in middle school; and 4) believed instruction time for sexuality education in the high schools should either remain the same or be increased. In addition, a significant increase in support for sexuality education occurred from the beginning of the survey to the end, suggesting that the instrument itself may have served as an educational tool for respondents. The characteristics of registered voters who supported sexuality education at the beginning of the survey and at the end were examined and compared. These results may assist in the development of educational and marketing strategies designed to build support for school-based sexuality education programs in South Carolina and elsewhere. 相似文献
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HD Mercer LD Rollins GG Carter RP Gural DW Bourne LW Dittert 《Canadian Metallurgical Quarterly》1977,66(8):1198-1200
Fifteen Aberdeen Angus steers, 295-364 kg, were dosed with either 4.4 or 11 mg of oxytetracycline hydrochloride/kg im. The antimicrobial activity of the serum was determined periodically, and the resulting data were treated statistically to determine the sources of variation. Variance in serum levels of oxytetracycline activity was attributed to dose, time of bleeding, order of dosing, animal, and assay. The total variance component was proportionately greater for the 11-mg/kg dose than for the 4.4-mg/kg dose. Animal variance increased with the higher dose level of oxytetracycline. The influence of dose on serum level was tested by applying a t test to the mean serum levels and their standard deviations at each bleeding time. The 4.4- and 11-mg/kg serum levels were significantly different (p less than 0.01) at all bleeding times. The 4.4-mg/kg serum levels mutliplied by 2.5 were not significantly different (p less than 0.05) from the 11-mg/kg serum levels at all bleeding times. 相似文献
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Cilioretinal arteries. A study based on review of stereo fundus photographs and fluorescein angiographic findings 总被引:1,自引:0,他引:1
The incidence of cilioretinal arteries in 2,000 eyes of 1,000 consecutive patients was determined by review of stereo color fundus photographs and fluorescein angiographs. One or more cilioretinal arteries were present in 49.5% of all patients or in 32.1% of the eyes. The arteries occurred bilaterally in 14.6% and contributed to some portion of the macular circulation in 18.7% of the patients. A great deal of variability of size, number, and distribution of cilioretinal vessels was observed. Prior studies that were based on direct visualization of the fundus have reported cilioretinal arteries in 7% to 29.6% of patients examined. Careful review of stereo fundus photographs and early phase fluorescein angiographs aided in the observation of these vessels that might otherwise have been unrecognized. We believe the method of review accounts for the high incidence of cilioretinal arteries in our series. 相似文献
90.
The effects of anemia during lead exposures were studied using an infant baboon animal model. When the hemoglobin concentration was reduced to less than 70% of normal, a marked blood lead increase was observed and the free erythrocyte porphyrin value, aminolevulinic acid dehydratase activity and reticulocyte counts increased. Special emphasis should be placed on nutritional effects in lead exposures. 相似文献