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21.
Laboratory studies suggest that ghrelin is involved in bone metabolism, but studies of ghrelin and bone in humans are limited. We studied sex-specific associations of ghrelin with BMD, NTX, and bone loss. Ghrelin was not associated with BMD or bone loss in either sex. There was a significant inverse association with NTX in men but not in women. INTRODUCTION: Ghrelin is a gastric hormone recently shown to be associated with bone metabolism in animal and in vitro studies. Studies in humans are limited. We investigated the association of ghrelin with BMD, the bone resorption marker N-telopeptide (NTX), and bone loss in older men and women. MATERIALS AND METHODS: Participants were 977 community-dwelling men and non-estrogen-using postmenopausal women, 50-91 years of age. Plasma ghrelin was measured by radioimmunoassay from blood obtained between 1984 and 1987. Between 1988 and 1991, BMD was measured at the midshaft radius by single photon absorptiometry and at the femoral neck, total hip, and lumbar spine by DXA. Axial BMD measurements were repeated an average of 4 years later in 544 participants. Bone turnover was assessed by NTX in urine obtained at the same time as the initial BMD. Multiple regression analyses were used to test sex-specific associations of ghrelin with BMD, NTX, and bone loss in both sexes. RESULTS: No significant ghrelin-BMD or ghrelin-bone loss associations were observed in either sex, after adjusting for age and body mass index (BMI). Ghrelin was inversely associated with NTX in men and positively associated with NTX in women, independent of age. After adjusting for both age and BMI, this association reached statistical significance in men and was weakened in women. CONCLUSIONS: Ghrelin may be associated with bone turnover, but there is no evidence for an association with BMD or short-term change in BMD in older adults.  相似文献   
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BACKGROUND: The utility of combining strategies of myocardial protection was studied in intact rat hearts subjected to 1 hour of ischemia and 40 minutes blood reperfusion. METHODS: Lewis rats (n = 48) were divided into 4 transplant groups. Twenty-four hearts were arrested by coronary perfusion with hypothermic Celsior solution at 60 mm Hg. The aortic valve was punctured to introduce volume into the left ventricle (LV), and the hearts were abdominally isografted. Animals were either given both the antioxidant probucol (300 mg/kg) and the sodium-hydrogen exchange inhibitor cariporide (5 mg/kg) (CP; n = 6), just cariporide (CAR; n = 6), just probucol (PROB; n = 6), or neither drug (CON; n = 6). After 40 minutes of blood reperfusion, transplanted hearts were rearrested. The control recipients' native hearts (native; n = 6) were also arrested. Postmortem LV compliance relations and myocardial water content (MWC) were measured. RESULTS: Grafts protected by probucol were significantly more compliant than controls and significantly less compliant than grafts protected by cariporide alone and with both cariporide and probucol (p = 0.0001, analysis of variance). Compliance relations for CP overlapped those for CAR. All grafts were less compliant than natives. MWC was significantly greater in controls and PROB than in natives. CONCLUSIONS: Pretreatment with cariporide in the setting of ischemia-reperfusion injury provides greater protection against the development of diastolic abnormalities than probucol when Celsior solution is used for both arrest and preservation. In this model, there is no advantage to combining the drugs, supporting the hypothesis that there is an overlapping mechanism of protection.  相似文献   
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We report on a case of keratoconus in identical twins who were brought up in Christchurch, New Zealand. Videokeratoscopy using an EyeSysa (EyeSys Laboratories, Houston, Texas, USA) revealed not only marked differences in severity of keratoconus between the sisters, but also non-equivalent cone types. Both twin sisters reported an exacerbation of their keratoconus during pregnancy and during breast feeding. Various factors affecting the development and progression of keratoconus are discussed. (Clin Exp Optom 1995; 78: 4: 125–129)  相似文献   
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Background: Pain after amputation is common but difficult to treat, and few controlled treatment studies exist.

Methods: In the current study, 94 treatment-naive posttraumatic limb amputees with phantom pain (intensity: mean visual analog scale score [0-100], 40 [95% confidence interval, 38-41]) were randomly assigned to receive individually titrated doses of tramadol, placebo (double-blind comparison), or amitriptyline (open comparison) for 1 month. Nonresponders were crossed over to the alternative active treatment.

Results: After 1 month, phantom pain intensity was 1 (0-2) in the 48 tramadol responders (mean dose, 448 mg [95% confidence interval, 391-505 mg]), 0 (0-0) in the 40 amitriptyline responders (55 [50-59] mg), and 0 (0-0) in the 2 placebo responders, with similar effects on stump pain. Cytochrome P-450 2D6 slow metabolizers derived greater analgesia from tramadol and less from amitriptyline compared with fast metabolizers in the first treatment week (P < 0.01). Electrical pain thresholds increased and pain during suprathreshold stimulation decreased markedly on the stump and, to a lesser extent, on the contralateral limb after 1 month of treatment with amitriptyline or tramadol. Adverse effects were minor in all groups, but more common with tramadol.  相似文献   

27.
This article is an overview of the promotion function as a part of the ATM's marketing mix. It approaches various promotion decision areas from a managerial perspective, focusing upon some key components of promotion planning. Rather than provide specific operational or implementation details (how to write a brochure) it is more conceptual in nature and offers a framework for promotion planners. The article addresses promotion management, promotion objectives, analysis for promotion planning, the promotion mix, and addresses the benefits and limitations of some specific promotion tools available to the ATM manager. It treats ATMs as a service and reveals specific implications for promotion strategy dictated by services. The article also reports promotion tools employed by Alabama ATMs citing data from the Alabama study.  相似文献   
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We have evaluated the spatial relationship between clotted vasculature and the structural integrity of layer V cortical neurons in YFP (yellow fluorescent protein)-H transgenic mice 2 to 10 h after photothrombotic stroke. Fortuitously, ischemic zones could be finely mapped about dysmorphic YFP labeled axons and dendrites using histology since Texas-red dextran used to assess blood flow in vivo was trapped within fixed clotted vessels. Ischemic damage to layer V neurons located at the border of ischemia was contained within apical tuft spiny dendritic structures and did not propagate to spines on the more proximal region of the apical dendrite. The lateral spread of dendritic damage decayed sharply with distance from the edge of ischemia (50% reduction in beaded dendrites within approximately 100 microm) and increased with time up to 6 h after stroke but not thereafter. Axonal damage also increased with time but extended further laterally than dendritic damage, up to 500 microm from the stroke core. Apoptotic and necrotic cell death cascades were activated 6 h after stroke; however, only within 300 microm of the ischemic core. These data suggest that the axonal and dendritic circuitry of neurons located 300 microm outside of an ischemic zone can be relatively free of damage or commitment to cell death suggesting that they may be in an ideal position to contribute to functional recovery. Given that ischemic damage may have a larger effect on circuitry involving superficial dendrites and projecting axons, it is conceivable that surviving peri-infarct neurons may have unique structural and functional properties.  相似文献   
30.
BACKGROUND: Unsedated office-based laser surgery (UOLS) of the larynx and trachea has significantly improved the treatment options for patients with laryngotracheal pathology including recurrent respiratory papillomas, granulomas, leukoplakia, and polypoid degeneration. UOLS delivered by flexible endoscopes has dramatically impacted office-based surgery by reducing the time, costs, and morbidity of surgery. OBJECTIVES: To review our experience with 443 laryngotracheal cases treated by UOLS. METHODS: The laser logbooks at the Center for Voice and Swallowing Disorders were reviewed for UOLS, and the medical and laryngological histories were detailed, as were the treatment modalities, frequencies, and complications. RESULTS: Of the 443 cases, 406 were performed with the pulsed-dye laser, 10 with the carbon-dioxide laser, and 27 with the thulium: yttrium-aluminum-garnet laser. There were no significant complications in this series. A review of indications and wavelength selection criteria is presented. CONCLUSION: Unsedated, office-based, upper aerodigestive tract laser surgery appears to be a safe and effective treatment option for many patients with laryngotracheal pathology.  相似文献   
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