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1-Deamino-8 D-arginine vasopressin (DDAVP) has been used effectively to normalize the bleeding time in various hemostatic disorders. In von Willebrand disease the reduction in bleeding time is due to the preferential release of large multimers of von Willebrand factor from endothelial cells. However, since the bleeding time correction in patients with uremia and liver disease is independent of the release of von Willebrand antigen and activity, other mechanisms of action of DDAVP need to be considered. Endothelial cells generate several thromborepellant factors including 13-hydroxyoctadecadienoic acid (13-HODE), an inhibitor of platelet adhesion to subendothelium. Using cultured fetal bovine aortic endothelial cells (FBAECs), we have investigated whether DDAVP modulates the production of 13-HODE. We have demonstrated that 14C-linoleic acid labeled FBAECs release several oxygenated derivatives of linoleic acid following a 120 min incubation in the presence of serum. One of these products was identified by chromatographic procedures as 13-HODE. The production of 13-HODE was decreased significantly by DDAVP (1-100 ng/ml) with maximal reduction (approx. 25%) seen at 1 ng/ml of DDAVP. While vehicle treated control FBAECs generated 6780 +/- 690 cpm of 13-HODE per 10(6) cells (mean +/- SE, n = 8), DDAVP treated FBAECs produced 4950 +/- 310 (P < 0.01), 5390 +/- 390 (P < 0.01), and 5720 +/- 410 cpm (P < 0.05) of 13-HODE at 1, 10, and 100 ng/ml DDAVP respectively. Our findings of a decrease in 13-HODE would explain the previously observed morphologic changes of increased platelet adhesion to subendothelium following DDAVP infusion and contributes to our understanding of the mode of action of this therapeutic agent in hemostatic disorders. 相似文献
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AIM: The aim of the study was to explore the information needs of informal carers, and how information from health professionals can become more effective for families caring for people with epilepsy. METHODS: A combined methodology was used, comprising an interview study and a survey. Twelve in-depth interviews with carers were carried out. The questionnaire was developed using the interview data, to which 70 carers responded. RESULTS: Four main themes have been drawn from the study. Carers' of people with epilepsy have a need for improved and more appropriate levels of information giving by health professionals in both primary and secondary care. Carers' perceived self-efficacy expectations in seeking information are positive but they do not always feel listened to. Carers' prefer to receive information in a one-to-one setting but also need information from formats other than leaflets. Carers' perceive barriers to having their information needs met, such as their needs being unrecognised in relation to the person with epilepsy. 相似文献
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Kevin L Moss James D Beck Sally M Mauriello Steven Offenbacher Raymond P White 《Journal of oral and maxillofacial surgery》2007,65(5):958-963
PURPOSE: This study was designed to identify risk indicators for the prevalence at enrollment and incidence over 36 months of periodontal pathology and coronal caries experience affecting third molars in a community-based study of people over 65 years of age. SUBJECTS AND METHODS: Data from a subsample of 810 dentate subjects from the Piedmont 65+ Study were available for analyses. All visible teeth were examined. Periodontal probing measures were taken at 2 sites, mesiobuccal and buccal/facial. Clinical data on caries experience were collected by visual-tactile examination. At enrollment, 340 subjects had at least 1 visible third molar; all were examined for caries experience. Periodontal probing measures were available for 277 of these same subjects. The significance of the possible risk indicators for periodontal pathology and caries affecting third molars was determined by chi(2) tests. Statistical significance was set at .05. Logistic multivariable models were used to derive odds ratios and 95% confidence intervals. RESULTS: African-American subjects were more likely to have visible third molars (P < .01). Caucasian subjects were more likely to have third molar coronal caries experience (P < .01), as were subjects with greater than a high school education and those with a dental visit within 3 years (both P < .01). However, African American subjects were more likely to have periodontal pathology, CALs >/= 3 mm on third molars (P < .01), as were those who used tobacco (P < .01). None of the other risk indicators we studied were associated with progression of periodontal pathology or coronal caries experience on visible third molars. CONCLUSION: In this population study of senior adults, Caucasians and African Americans appear to have different levels of risk for caries experience and periodontal pathology affecting retained third molars. 相似文献
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Susan R. Gartner Catherine L. Gilliss Julie A. Shinn Patricia A. Sparacino Sally Rankin Maribelle Leavitt Martha Price Mark Hudes 《Journal of advanced nursing》1988,13(5):649-661
To enhance individual and family health during recovery from heart surgery, this study employed nursing interventions based on self-efficacy and family stress theory during the hospitalization period and for 3 months thereafter. The effectiveness of the interventions were assessed through a randomized trial in which 67 prospective bypass and valve surgery patients, aged 30-77 years, and their spouses, were allocated either the experimental interventions or usual care and followed for 6 months. At 3 months post-surgery, the only statistically significant differences between the experimentals and controls were on perceived self-efficacy for lifting and tolerating emotional distress. At 6 months no significant differences were found on individual or family measures. Analyses revealed that age, gender and preoperative cardiac status significantly affected individual recovery. The study is continuing with a larger sample in order to explicate the recovery process and to better determine whether a low intensity nursing intervention can effect changes in individual and family recovery. 相似文献
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