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Stanley M. Garn Timothy V. Sullivan Sally A. Decker Frances A. Larkin Victor M. Hawthorne 《American journal of human biology》1992,4(1):57-67
As shown in 744 adult men and women aged 30–49 at entry and followed for 21.4 ± 0.9 years there is continuing subperiosteal expansion in both sexes as well as continuing and increasing endosteal surface resorption. In this longitudinal study, bone loss (as shown by medullary cavity expansion) begins by the 5th decade and increases thereafter. The smaller gains at the outer bone surface are essentially independent of the larger losses at the inner (endosteal) surface and neither functionally nor causally related. Though bone loss and net bone loss is nearly as great in men as in women, absolutely speaking, two-decade bone loss constitutes a larger percentage of the initially smaller bone mass in the female. In both sexes subperiosteal apposition (delta TA) and endosteal resorption (delta MA) are bone-size dependent though in diametrically opposite directions. These trends in two-decade bone change are not affected by smoking behavior, alcoholic beverage usage, antihypertensive usage, or early menopausal age. Similarly, the long-term bone changes prove to be independent of energy and mineral intakes and to long-term changes in calcium, phosphorus, magnesium, and vitamin D intake. Though dietary intakes do not predict long-term bone changes, the amount of tissue bone present at entry is highly correlated (> 0.93) with tissue bone 21.4 years later in men and women alike. Accordingly, only a small amount of intraindividual cortical variance in the later years still remains to be explained by life-style, dietary, medication, and error variables. 相似文献
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? This paper suggests that (i) the dominance of an individualistic philosophy of nursing, (ii) nurses' own perceptions of their role and (iii) the hospital:community divide are all obstacles to health promotion being well integrated into nursing practice. ? It explores how these obstacles need to be overcome in order for the new health promoting nurse to emerge in practice. ? This is an attempt to clearly demonstrate ‘who’ the health promoting nurse is, ‘what’ she/he does, ‘how’ she/he works and ‘where’ she/he works. 相似文献
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Sally A. Hill Louise E. Sampson David J. Chaplin 《International journal of cancer. Journal international du cancer》1995,63(1):119-123
Several agents have now been identified which exert their anti-tumour effects in large part via the tumour vasculature; these include TNFα and flavone acetic acid (FAA). More recently, Vincristine and Vinblastine have also been shown to cause a prolonged and selective decrease in tumour perfusion. Vinblastine, unlike FAA, causes no increase in plasma TNFα levels in mice bearing the CaNT tumour, suggesting 2 distinct mechanisms of anti-vascular activity for these structurally diverse agents. Since FAA and Vinblastine also show quite different normal tissue toxicities, which are separately dose-limiting, we have examined the strategy of combining these 2 agents. When Vinblastine preceded FAA by 24 hr or less, tumour growth delay was significantly enhanced without a concomitant increase in toxicity. The level of enhancement was not significantly reduced by a 5-fold decrease in Vinblastine dose, though any reduction in the dose of FAA caused a rapid reduction in treatment effectiveness. Investigation of the functional vasculature of treated tumours suggested that increased anti-vascular effects may contribute to the enhanced growth inhibition of the combined treatment. Our results demonstrate the potential benefit of combining 2 different classes of antivas-cular agent, using Vinblastine and FAA (or 5,6-MeXAA) as prototype drugs. 相似文献
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Sally A. Zifer DDS Deirdre R. Sams DDS MS Brad J. Potter DDS MS Rita Jerath MD 《Special care in dentistry》1994,14(5):208-211
Rheumatoid arthritis (RA) is an inflammatory disease of the synovium which may lead to proliferative and degenerative changes in the body's joints, including the temporomandibular joint (TM Joint). Although the exact etiology of rheumatoid arthritis remains unknown, it is suspected that the disease is often initiated by an infectious organism, or by genetic and/or environmental factors. Juvenile rheumatoid arthritis (JRA) is a chronic disease of childhood with a spectrum of joint involvement and associated systemic and other organ involvement. Five percent of all rheumatoid arthritis patients are children. In the United States, approximately 150,000 children are affected by IRA. With upper limb involvement, routine oral hygiene procedures become difficult. Dental evaluations/screenings may not be included in the initial team assessment of these patients until the TM Joint is affected; however, prior to this time, the patient may have had years of poor oral hygiene which could contribute to severe decay and early tooth loss. This case report describes the oral health status of a child with polyarticular juvenile rheumatoid arthritis and the specific recommendations for dental management. 相似文献