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排序方式: 共有506条查询结果,搜索用时 0 毫秒
91.
CM Magnusson IR Persson JA Baron A Ekbom R Bergstr?m HO Adami 《Canadian Metallurgical Quarterly》1999,80(2):231-236
BACKGROUND: We examined the cholesterol-lowering effects of a proprietary Chinese red-yeast-rice supplement in an American population consuming a diet similar to the American Heart Association Step I diet using a double-blind, placebo-controlled, prospectively randomized 12-wk controlled trial at a university research center. OBJECTIVE: We evaluated the lipid-lowering effects of this red-yeast-rice dietary supplement in US adults separate from effects of diet alone. DESIGN: Eighty-three healthy subjects (46 men and 37 women aged 34-78 y) with hyperlipidemia [total cholesterol, 5.28-8.74 mmol/L (204-338 mg/dL); LDL cholesterol, 3.31-7.16 mmol/L (128-277 mg/dL); triacylglycerol, 0.62-2.78 mmol/L (55-246 mg/dL); and HDL cholesterol 0.78-2.46 mmol/L (30-95 mg/dL)] who were not being treated with lipid-lowering drugs participated. Subjects were treated with red yeast rice (2.4 g/d) or placebo and instructed to consume a diet providing 30% of energy from fat, <10% from saturated fat, and <300 mg cholesterol daily. Main outcome measures were total cholesterol, total triacylglycerol, and HDL and LDL cholesterol measured at weeks 8, 9, 11, and 12. RESULTS: Total cholesterol concentrations decreased significantly between baseline and 8 wk in the red-yeast-rice-treated group compared with the placebo-treated group [(x+/-SD) 6.57+/-0.93 mmol/L (254+/-36 mg/dL) to 5.38+/-0.80 mmol/L (208+/-31 mg/dL); P < 0.001]. LDL cholesterol and total triacylglycerol were also reduced with the supplement. HDL cholesterol did not change significantly. CONCLUSIONS: Red yeast rice significantly reduces total cholesterol, LDL cholesterol, and total triacylglycerol concentrations compared with placebo and provides a new, novel, food-based approach to lowering cholesterol in the general population. 相似文献
92.
讨论了静态时序分析算法及其在IC设计中的应用。首先,文章讨论了静态时序分析中的伪路径问题以及路径敏化算法,分析了影响逻辑门和互连线延时的因素。最后通过一个完整的IC设计流程介绍了静态时序分析的应用。 相似文献
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94.
HO Williamson PB Underwood A Kreutner JF Rogers RS Mathur HR Pratt-Thomas 《Canadian Metallurgical Quarterly》1976,126(5):579-585
Six patients with a total of nine gonadoblastomas are presented; three--and possibly a fourth--had dysgerminomatous overgrowth which was massive in two patients. Calcification detected by abdominal films was present in three sufficient for preoperative diagnosis. All patients were found to have a Y stem line on peripheral leukocyte chromosome cultures except one patient, who had a 46 XX/45 XO karyotype. She was found to have Y chromatin bodies in the germ cells of her tumor which was in a normal ovary found at exploration for an ectopic pregnancy. Three were found in virilized phenotypic females investigated for amenorrhea, and two for therapy of pelvic masses due to dysgerminomatous overgrowth. Y chromatin studies are reported on gonadal tissue. 相似文献
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98.
介绍了低铬耐热铸铁(RTcr2)的生产过程,用1.5t/h冲天炉和选择化学成分为:ω(cr)1.5%-1.8%,ω(C)3.0%~3.3%,ω(Si)2.0%~2.5%,ω(Mn)≤0.8%,ω(P)、ω(S)≤0.10%的铁液,生产现场严格控制底焦高度、铬铁块度,石灰石加入量等,生产的耐热铸铁完全满足了产品的各项性能要求。 相似文献
99.
DONG‐KYU KIM WON‐WOONG PARK HO WON LEE SEONG‐HOON KANG YONG‐TAEK IM 《Journal of microscopy》2013,252(3):204-216
In this study, a rigorous methodology for quantifying recrystallization kinetics by electron backscatter diffraction is proposed in order to reduce errors associated with the operator's skill. An adaptive criterion to determine adjustable grain orientation spread depending on the recrystallization stage is proposed to better identify the recrystallized grains in the partially recrystallized microstructure. The proposed method was applied in characterizing the microstructure evolution during annealing of interstitial‐free steel cold rolled to low and high true strain levels of 0.7 and 1.6, respectively. The recrystallization kinetics determined by the proposed method was found to be consistent with the standard method of Vickers microhardness. The application of the proposed method to the overall recrystallization stages showed that it can be used for the rigorous characterization of progressive microstructure evolution, especially for the severely deformed material. 相似文献
100.
As a typical cross-cutting technology, cooling and refrigeration equipment is used for a variety of industrial applications. While cooling is often provided by electric compression cooling systems, thermal cooling systems powered by low-temperature waste heat could improve energy efficiency and promise a technical saving potential corresponding to 0.5?% of the total electricity demand in the German industry. In this paper, we investigate the current and future cost-effectiveness of thermal cooling systems for industrial companies. Our focus is on single-stage, closed absorption and adsorption cooling systems with cooling powers between 40 and 100?kW, which use low-temperature waste heat at temperature levels between 70?°C and 85?°C. We analyse the current and future cost-effectiveness of these alternative cooling systems using annual cooling costs (annuities) and payback times. For a forecast until 2015, we apply the concept of experience curves, identifying learning rates of 14?% (absorption machines) and 17?% (adsorption machines) by an expert survey of the German market. The results indicate that thermal cooling systems are currently only cost-effective under optimistic assumptions (full-time operation, high electricity prices) when compared to electric compression cooling systems. Nevertheless, the cost and efficiency improvements expected for this still young technology mean that thermal cooling systems could be more cost-effective in the future. However, depending on future electricity prices, a high number of operating hours is still crucial to achieve payback times substantially below 4?years which are usually required for energy efficiency measures to be widely adopted in the industry. 相似文献