排序方式: 共有47条查询结果,搜索用时 718 毫秒
41.
JR Downs M Clearfield S Weis E Whitney DR Shapiro PA Beere A Langendorfer EA Stein W Kruyer AM Gotto 《Canadian Metallurgical Quarterly》1998,279(20):1615-1622
CONTEXT: Although cholesterol-reducing treatment has been shown to reduce fatal and nonfatal coronary disease in patients with coronary heart disease (CHD), it is unknown whether benefit from the reduction of low-density lipoprotein cholesterol (LDL-C) in patients without CHD extends to individuals with average serum cholesterol levels, women, and older persons. OBJECTIVE: To compare lovastatin with placebo for prevention of the first acute major coronary event in men and women without clinically evident atherosclerotic cardiovascular disease with average total cholesterol (TC) and LDL-C levels and below-average high-density lipoprotein cholesterol (HDL-C) levels. DESIGN: A randomized, double-blind, placebo-controlled trial. SETTING: Outpatient clinics in Texas. PARTICIPANTS: A total of 5608 men and 997 women with average TC and LDL-C and below-average HDL-C (as characterized by lipid percentiles for an age- and sex-matched cohort without cardiovascular disease from the National Health and Nutrition Examination Survey [NHANES] III). Mean (SD) TC level was 5.71 (0.54) mmol/L (221 [21] mg/dL) (51 st percentile), mean (SD) LDL-C level was 3.89 (0.43) mmol/L (150 [17] mg/dL) (60th percentile), mean (SD) HDL-C level was 0.94 (0.14) mmol/L (36 [5] mg/dL) for men and 1.03 (0.14) mmol/L (40 [5] mg/dL) for women (25th and 16th percentiles, respectively), and median (SD) triglyceride levels were 1.78 (0.86) mmol/L (158 [76] mg/dL) (63rd percentile). INTERVENTION: Lovastatin (20-40 mg daily) or placebo in addition to a low-saturated fat, low-cholesterol diet. MAIN OUTCOME MEASURES: First acute major coronary event defined as fatal or nonfatal myocardial infarction, unstable angina, or sudden cardiac death. RESULTS: After an average follow-up of 5.2 years, lovastatin reduced the incidence of first acute major coronary events (1 83 vs 116 first events; relative risk [RR], 0.63; 95% confidence interval [CI], 0.50-0.79; P<.001), myocardial infarction (95 vs 57 myocardial infarctions; RR, 0.60; 95% CI, 0.43-0.83; P=.002), unstable angina (87 vs 60 first unstable angina events; RR, 0.68; 95% CI, 0.49-0.95; P=.02), coronary revascularization procedures (157 vs 106 procedures; RR, 0.67; 95% CI, 0.52-0.85; P=.001), coronary events (215 vs 163 coronary events; RR, 0.75; 95% CI, 0.61-0.92; P =.006), and cardiovascular events (255 vs 194 cardiovascular events; RR, 0.75; 95% CI, 0.62-0.91; P = .003). Lovastatin (20-40 mg daily) reduced LDL-C by 25% to 2.96 mmol/L (115 mg/dL) and increased HDL-C by 6% to 1.02 mmol/L (39 mg/dL). There were no clinically relevant differences in safety parameters between treatment groups. CONCLUSIONS: Lovastatin reduces the risk for the first acute major coronary event in men and women with average TC and LDL-C levels and below-average HDL-C levels. These findings support the inclusion of HDL-C in risk-factor assessment, confirm the benefit of LDL-C reduction to a target goal, and suggest the need for reassessment of the National Cholesterol Education Program guidelines regarding pharmacological intervention. 相似文献
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A. Clearfield R. Guerra A. Oskarsson M.A. Subramanian W. Wang 《Materials Research Bulletin》1983,18(12):1561-1567
Sodium zirconium phosphates of the type Na1+4x Zr2?x (PO4)3 were prepared from mixtures of Na3PO4-ZrO2-ZrP2O7 in sealed platinum tubes at temperatures of 900 – 1200°C. Stoichiometric NaZr2 (PO4)3 (x = 0) was found not to exist. Instead, a solid solution in the range x = 0.02 ? 0.06 was found, with a slight difference in unit cell dimensions obtained. A second solid solution region was found with x = 0.88 – 0.93. At still higher values of x, a stoichiometric phase with hexagonal unit cell dimensions of and was obtained. Finally a phase of composition Na7Zr0.5 (PO4)3 was synthesized at the highest values of x. Attempts to prepare Na5+x ZrSix-P3?xO12 always yielded NASICON and Na7Zr0.5 (PO4)3. 相似文献
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AG Lacko BJ Kudchodkar WW Loney MB Clearfield S Weis 《Canadian Metallurgical Quarterly》1998,36(6):389-392
A matter of debate is whether the use of a video-endoscope impairs visual orientation and manual precision in endonasal surgery. We investigated the influence of video-endoscopy compared to endoscopy on stereoacuity in a model of the nasal cavity. Twenty medical staff members were asked to touch defined points in a spatial model of the nasal cavity as quickly as possible and in correct order using 0 degree and 30 degrees endoscopes, looking directly through the endoscope or looking at a video monitor connected to a CCD camera on the endoscope. Time, number of omissions of points and faults in point sequence were recorded. Manipulations were significantly quicker when the "operative field" was seen directly through the endoscope compared to orientation from the monitor for both 0 degree endoscope 96 +/- 4.7 s. vs. 108 +/- 5.6 s. and 30 degrees endoscope 84 +/- 3.9 s. vs. 96 +/- 5.5 s. (+/- SEM). There was no difference in number of omissions and faults in sequence between "endoscope" and "video-endoscope." The fact that the use of a video-endoscope did not increase the number of faults in our experiment does not support the notion that performing endoscopic sinus surgery using a monitor is unsafe. In the hands of the participants who were experienced with the endoscope, however, the use of a video-endoscope slowed down manipulations to a significant degree. To which extent this may be due to the effect of training or to superiority of the endoscope per se will remain a matter of discussion until a group of experienced video-endoscopists will have repeated the study. 相似文献
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The recent article “Sodium Hydroxide Anodization of Ti-6A1-4V Adherends” by Filbey, Wightman and Progar' is commendable in that a wide variety of analytical techniques has been used to study the surface preparation first reported by Kennedy, Kohler and Poole. We too have conducted in-depth studies of surface preparations for Ti-6A1-4V adherends with recent emphasis on chromic acid and sodium hydroxide anodization (CAA and SHA, respectively). Our initial results were in agreement with those presented by Filbey et al. (hereafter “the authors”) regarding surface composition and oxide sputter-etching efficiency. However, the results of more detailed work have shown that these observations (and the subsequent conclusions) may be influenced by instrumentation effects. We wish to highlight these briefly. 相似文献
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Clearfield H.M. Young J.L. Wijeyesekera S.D. Logan E.A. 《Advanced Packaging, IEEE Transactions on》2000,23(2):247-251
Chip scale packaging continues to draw attention for applications that require high performance or small form factor solutions. The term chip scale package (CSP) has become synonymous with “fine pitch BGA” as the distinction between a ball grid array (EGA) and some chip scale packages becomes nearly indistinguishable. The cost of chip scale packages also continues to draw attention as one of the barriers to wide scale industry adoption. Sometimes lost in the chip scale debate is the discussion about wafer level chip scale packages, which offer the fastest path to small form factor, high performance and cost effective solutions. In this paper, we describe an approach to wafer level chip scale packaging that is an extension of integrated passive device processing, which results in low cost 相似文献