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Sex and age differences in lipoprotein subclasses measured by nuclear magnetic resonance spectroscopy: the Framingham Study 总被引:1,自引:0,他引:1
Freedman DS Otvos JD Jeyarajah EJ Shalaurova I Cupples LA Parise H D'Agostino RB Wilson PW Schaefer EJ 《Clinical chemistry》2004,50(7):1189-1200
BACKGROUND: The sex differential in coronary heart disease (CHD) risk, which is not explained by male/female differences in lipid and lipoprotein concentrations, narrows with age. We examined whether this differential CHD risk might, in part, be attributable to the sizes of lipoprotein particles or concentrations of lipoprotein subclasses. METHODS: We analyzed frozen plasma samples from 1574 men and 1692 women from exam cycle 4 (1988-1990) of the Framingham Offspring Study. Nuclear magnetic resonance (NMR) spectroscopy was used to determine the subclass concentrations and mean sizes of VLDL, LDL, and HDL particles. Concentrations of lipids and apolipoproteins were measured by standard chemical methods. RESULTS: In addition to the expected sex differences in concentrations of triglycerides, LDL-cholesterol, and HDL-cholesterol, women also had a lower-risk subclass profile consisting of larger LDL (0.4 nm) and HDL (0.5 nm) particles. The sex difference was most pronounced for HDL, with women having a twofold higher (8 vs 4 micromol/L) concentration of large HDL particles than men. Furthermore, similar to the narrowing of the sex difference in CHD risk with age, the observed male/female difference in HDL particle size also decreased with age. Although lipoprotein particle sizes were highly correlated with lipid and lipoprotein concentrations, the sex differences in the mean sizes of lipoprotein particles persisted (P <0.001) even after adjustment for lipid and lipoprotein concentrations. CONCLUSIONS: Women have a less atherogenic subclass profile than men, even after accounting for differences in lipid concentrations. 相似文献
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Marion Danis MD Susan Dorr Goold MA MD MHSA † Carol Parise PhD ‡ Marjorie Ginsburg MPH § 《Health expectations》2007,10(3):236-247
OBJECTIVE: To demonstrate that employees can gain understanding of the financial constraints involved in designing health insurance benefits. BACKGROUND: While employees who receive their health insurance through the workplace have much at stake as the cost of health insurance rises, they are not necessarily prepared to constructively participate in prioritizing their health insurance benefits in order to limit cost. DESIGN: Structured group exercises. SETTING AND PARTICIPANTS: Employees of 41 public and private organizations in Northern California. INTERVENTION: Administration of the CHAT (Choosing Healthplans All Together) exercise in which participants engage in deliberation to design health insurance benefits under financial constraints. MAIN OUTCOME MEASURES: Change in priorities and attitudes about the need to exercise insurance cost constraints. RESULTS: Participants (N = 744) became significantly more cognizant of the need to limit insurance benefits for the sake of affordability and capable of prioritizing benefit options. Those agreeing that it is reasonable to limit health insurance coverage given the cost increased from 47% to 72%. CONCLUSION: It is both possible and valuable to involve employees in priority setting regarding health insurance benefits through the use of structured decision tools. 相似文献
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Abstract – The occurrence of supra- and subgingival calculus, gingival inflammation, periodontal pockets ( 5 mm) and alveolar bone loss was determined in children (10-19 yr) with Down's syndrome (D-S) and in an aged- and sex-matched control group ( n = 39). Of D-S children ( n = 71), 39 of the patients (mean age 15.5 yr) cooperated in a clinical and roentgenologic examination. Alveolar bone loss was determined around incisors and first molars on intraoral radiographs when the distance between cementoenamel junction (GEJ) to alveolar crest (AC) exceeded 2.0 mm. Alveolar bone loss was diagnosed in 39% of the D-S children compared to 3% in the control group ( P <0.001). Of the total number of sites examined on radiographs the distance from CEJ to AC exceeded 2.0 mm in 8% in the D-S group compared to 0.2% in the control group ( P <0.001). The frequency of sites with alveolar bone loss in D-S children was significantly ( P <0.001) higher around the mandibular incisors compared to first molars. The study shows that early signs of periodontitis are frequently seen in D-S children as early as 11 yr of age and the lesions are first diagnosed in the mandibular anterior region. 相似文献
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S. Grasselli R. Guerciolini V. Iadevaia P. Parise P. Gresele G. G. Nenci 《European journal of clinical pharmacology》1987,32(2):207-210
Summary We have studied the effect of indobufen, a cyclo-oxygenase blocking agent which has proved useful in patients with obstructive vascular disease, on red blood cell (RBC) filterability in vitro and in a pilot study ex vivo.The addition of indobufen in vitro to blood samples from 10 healthy volunteers did not significantly modify RBC deformability.We evaluated the ex vivo effect of indobufen (200 mg bd) in 14 patients with obstructive vascular disease. A significant improvement in RBC deformability was noted on the 5th, 14th, and 28th days of treatment, 2 h after the morning dose. Acetylsalicylic acid given to 6 similar patients had no effect suggesting that the positive haemorheological effect of indobufen is probably not linked to its cyclooxygenase blocking effect. 相似文献
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Mewissen MW; Erickson SJ; Foley WD; Lipchik EO; Olson DL; McCann KM; Schreiber ER 《Radiology》1989,173(1):155-157
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein. 相似文献
50.
Myocardial tagging in polar coordinates with use of striped tags 总被引:1,自引:0,他引:1
Regional deformation abnormalities in the heart wall provide a good indicator of ischemia. Myocardial tagging with magnetic resonance imaging is a new method of assessing heart wall motion during contraction. Current methods of myocardial tagging either do not provide two-dimensional information or lack a coordinate system well adapted to the morphology of the heart. In this article, the authors describe a new tagging method that provides a true polar coordinate system, with both radial and angular dimensions. This is accomplished with use of a section-selective version of spatially modulated magnetization resulting in striped tags (STAGs). These STAG planes are placed in the myocardium in a star pattern so that they intersect on the long axis of the heart and stripes appear through the width of the heart wall. In the short-axis view during contraction, rotation around the long axis yields angular information such as shear and twist, while separation of the stripes within the myocardium permits measurement of radial thickening. Therefore, this method provides a coordinate system for calculating two-dimensional strain that is adapted to the morphology of the left ventricle. 相似文献