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11.
BACKGROUND: This study examines the relationship between income, health insurance, and usual source of care characteristics and screening and management of hypertension. METHODS: This is a secondary analysis of data from the 1987 National Medical Expenditure Survey. Adult survey respondents constitute a sample representative of the total adult noninstitutionalized US population. Screening, follow-up care, and pharmacologic treatment for hypertension were examined among low income individuals, the uninsured, those without a usual source of care place, and those without a particular usual source of care physician. RESULTS: The uninsured, individuals without a usual source of care place, and those without a particular usual source of care physician received less screening, follow-up care, and pharmacologic treatment for hypertension. Income did not affect receipt of hypertensive care. CONCLUSIONS: Lack of health insurance and lack of a usual source of care are barriers to hypertensive care. Policies that increase access to health insurance or to usual source of care physicians may enable more individuals to attain control of hypertension. 相似文献
12.
Ambient, biological, and biological effect monitoring of exposure to polycyclic aromatic hydrocarbons (PAHs) 总被引:1,自引:0,他引:1
BA Hatjian JW Edwards J Harrison FM Williams PG Blain 《Canadian Metallurgical Quarterly》1995,77(1-3):271-279
A novel strategy was utilised to assess the risk to health from exposure to polycyclic aromatic hydrocarbons (PAHs). Ambient monitoring was carried out by personal sampling. Urinary thioethers (UTh) and urinary 1-hydroxypyrene (1-HP) were utilised for biological monitoring. Urinary d-glucaric acid (UDGA) and sister chromatid exchange (SCE) in peripheral blood lymphocytes were used as biological effect markers. The population was categorised into exposed and control groups according to the external dose of PAHs. The excretion of 1-HP in the controls over the 3-day period showed a relatively stable baseline, while the exposed showed a significant increase over the same period of time. SCE frequency in the exposed population was significantly different from controls. 相似文献
13.
本文着重对图象多分辨率技术进行分析,并提出了相应的系统结构成框架,同时还探讨了以图象多分辨率处理为核心,采用了 新的压缩编码的可能性。 相似文献
14.
OBJECTIVE: The purpose of this study was to compare click-evoked otoacoustic emissions (COAEs) of subjects having similar auditory thresholds but different age ranges. It is well known that elevated hearing thresholds are common with increasing age and that deterioration of outer hair cells is often noted in cases of hearing loss due to increased age. It has also been reported that evoked otoacoustic emissions (EOAEs) decrease with increased age. However, there is still some question whether changes in EOAEs with aging are associated with the increased hearing threshold or whether there is some additional effect of aging that enfluences EOAEs. DESIGN: COAE input/output functions and synchronized spontaneous OAEs (SSOAEs) were measured in two groups of subjects having similar auditory thresholds, one ranging in age from 19 to 29 yr, the other ranging in age from 40 to 61 yr. Mixed-model ANOVAs were performed to determine whether there were any statistically significant differences in COAEs based on age group. RESULTS: There were no statistically significant differences in COAE level or COAE threshold between age groups. Significant differences in COAEs were found for subjects based on whether they had measurable SSOAEs, regardless of age. CONCLUSIONS: Age does not significantly reduce COAE level nor increase COAE threshold. Other factors, such as presence of SSOAEs and hearing loss, undoubtedly have more influence on COAEs than the factor of age. 相似文献
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16.
Although the good appearance and biocompatibility of dental porcelains, failures are still of considerable concern because of the limited properties to all ceramic system. Physical properties that might be considered ideal include high strength, resistance to abrasion, and resistance to the hostile oral environment. Porcelain has been considered by many of its physical characteristic are similar to those of enamel. In 1983 a new modality of treatment, the etched porcelain restoration was introduced by Simonsen and Calamia. Numerous investigations have shown the strength of the etched porcelain bonded to composite resin and also the clinical success of this porcelain to be used as laminated veneers and etched inlays and onlays. 相似文献
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18.
AA Ovchinnikov VE Tsvettsikh BA Berdichevski? VN Lykov VR Suktanbaev AV Murychev 《Canadian Metallurgical Quarterly》1996,20(4):7-9
Through TCD test, observation on the blood flow dynamics change before and after treatment with 31 cases of the child cerebral atrophy was made. It is found that scalp therapy is able to speed up the blood flow of part artery, especially increase the even blood flow speed of MCA, ACA obviously (P < 0.05), which preliminary shows the mechanism of scalp therapy for child cerebral atrophy mean while. It is found that scalp therapy also has the function to restrain epilepsy. 相似文献
19.
BA Lawrence J Polse A DePina MM Allen NH Kolodny 《Canadian Metallurgical Quarterly》1997,34(5):280-283
The identity of a number of phosphorus-containing metabolites present in Synechocystis sp. PCC 6308 has been confirmed by 31P NMR spectroscopy. The presence of D-ribulose 1,5-bisphosphate (RuBP); DL-glyceraldehyde 3-phosphate (GlyP); D(-)3-phosphoglyceric acid (3PGA); D-ribulose 5-phosphate (Ru5P);6-phosphogluconic acid (6PGA); phosphoenolpyruvate (PEP); inorganic phosphate (Pi); uridine diphosphoglucose (UDPG); ADP and ATP were demonstrated by the pH dependence of their 31P NMR chemical shifts in spectra of perchloric acid cell extracts. Intracellular pH of cells was determined to be 7.5-7.7. 相似文献
20.
BA Stankiewicz JC Hutchins R Thomson DE Briggs RP Evershed 《Canadian Metallurgical Quarterly》1997,11(17):1884-1890
Flash pyrolysis-gas chromatography/mass spectrometry (py-GC/MS) was used to assess the quality and mechanism of protein preservation in the tissue of Iron Age bog bodies from Lindow, UK, and south-eastern Drenthe, The Netherlands. Abundant pyrolysis products of the fresh skin tissue, including 2,5-diketopiperazines of Pro-Gly, Pro-Ala, Pro-Val, Pro-Pro and Hyp, were readily assigned to specific amino acid or dipeptide moieties. Comparison of the pyrolysates of the bog-body tissues with that of modern samples revealed qualitative similarities suggesting good preservation of the collagen and non-collagenous proteins in the ancient tissues. Examination of the pyrolysates of samples of fresh calf skin, which had been treated with various vegetable tanning agents, clearly revealed markers of non-hydrolysable tannins including 1,2-benzenediol, 1,3-benzenediol and 1,2,3-benzenetriol, although chromatographic quality inevitably diminished with increasing functionalization of the compounds. Such markers were not detected in the pyrolysates of the bog-body tissues. Instead 4-isopropenylphenol, a characteristic pyrolysis product of Sphagnum moss, was detected in both solvent-extracted and base-treated samples of tissue. The presence of 4-isopropenylphenol in the pyrolysates of the bog-body tissues provides evidence that their preservation involves reactions of amino acids with sphagnum acid, and possibly other agents derived from the peat. The study constitutes the first chemical characterization of the pyrolysis products of modern and ancient collagen. 相似文献