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101.
102.
JL González CJ Russo D Goldowitz HO Sweet MT Davisson CA Walsh 《Canadian Metallurgical Quarterly》1997,17(23):9204-9211
The reeler mutation in mice produces an especially well characterized disorder, with systematically abnormal migration of cerebral cortical neurons. The reeler gene encodes a large protein, termed Reelin, that in the cortex is synthesized and secreted exclusively in the Cajal-Retzius neurons of the cortical marginal zone (D'Arcangelo et al., 1995). In reeler mutant mice, loss of Reelin protein is associated with a systematic loss of the normal, "inside-out" sequence of neurogenesis in the cortex: neurons are formed in the normal sequence but become localized in the cortex in a somewhat inverted, although relatively disorganized "outside-in" pattern. Here we show that the scrambler mutant mouse exhibits a loss of lamination in the cortex and hippocampus that is indistinguishable from that seen in the reeler mouse. We use BrdU birthdating studies to show that scrambler cortex shows a somewhat inverted "outside-in" sequence of birthdates for cortical neurons that is similar to that previously described in reeler cortex. Finally, we perform staining with the CR-50 monoclonal antibody (Ogawa et al., 1995), which recognizes the Reelin protein (D'Arcangelo et al., 1997). We show that Reelin immunoreactivity is present in the scrambler cortex in a normal pattern, suggesting that Reelin is synthesized and released normally. Our data suggest that scrambler is a mutation in the same gene pathway as the reeler gene (Relnrl) and is most likely downstream of Relnrl. 相似文献
103.
1 岩土与基础工程的现状
福建省地处我国东南沿海主要分布有软土地基区域和山区坡残积土、风化岩地基,地基工程特性极不稳定地层,结构复杂,因此给广大岩土与基础工程技术人员提出了许多新的课题,也因此带动我省岩土与基础工程领域不断向前发展。20多年来,特别是近十年来我省岩土与基础工程技术发展迅猛,从岩土的勘探与测试,天然地基利用和山地地基的开发利用,桩基技术,地基处理技术,基坑与边坡支护技术、检测与监测技术等方面,取得了显著的成绩和突破性的进展,具体表现在: 相似文献
104.
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
105.
基于表面形貌的裂纹萌生阶段滑移带表征 总被引:2,自引:2,他引:0
目的研究WaspaloyTM镍基高温合金在裂纹萌生阶段的表面形貌特征,找出最优表面形貌参数用以表征此阶段的滑移带特征。方法对WaspaloyTM镍基高温合金试样先机械抛光,然后采用标准金相技术分别进行电解抛光和化学蚀刻,得到两种不同的表面状态。对试样进行低周疲劳试验获得疲劳寿命,并采用透射电子显微镜(TEM)和三维表面轮廓仪,观测分析WaspaloyTM镍基高温合金在电解抛光和化学蚀刻处理后的表面形貌以及裂纹萌生阶段的表面形貌和滑移带特征。对测得的表面形貌参数进行方差分析和自助抽样统计计算,找出最优参数。结果试样在经过电解抛光和化学蚀刻后,三维表面形貌S_a(表面算数平均偏差)分别是0.72 nm和13.3 nm,试样疲劳寿命分别为800和700。两种制备状态下的样品,算术平均高度增量(ΔS_a=S_a(N)-S_a(N0))的差异非常小,且ΔS_a随疲劳加载周期(N)的增加而增加,当N100后,ΔS_a随N增加的速率减小。结论电解抛光后的表面质量更好,且表面质量越好,疲劳寿命越高。ΔS_a与表面制备方法无关,ΔS_a越大,表面越粗糙。经方差分析和自助抽样法计算分析,表面最大峰值(Sp)是最优表面形貌参数,该参数可用于区分滑移带内的损伤晶粒和未损伤晶粒。 相似文献
106.
本文以吉林省L县矿业生产为例,研究了矿区村民视角下矿业生产导致的环境污染现状,并对矿业生产中村民、政府和矿业企业之间的经济和环境关系进行了分析。研究结果表明,从村民视角来看矿业生产活动给矿区村民的生活环境造成了严重污染,主要集中在交通、卫生、安全、休息等方面;矿业生产中地方政府和矿企之间的地方保护主义为矿企的发展提供了便利。矿区村民在利益博弈中处于劣势,获得最少的经济效益并承担了环境恶化的后果,但当环境问题和经济利益发生冲突时,村民依然选择了向经济利益妥协。当环境纠纷发生时,村民一般的处理方式为个人出面或者是集体抗议,很少有村民采取依靠政府或者是法律途径来维护自己的合法权益。基于以上结论本文提出相关的建议,以期为治理矿业生产导致的环境问题献计献策。 相似文献
107.
108.
109.
Natthorn Intawiwat Elina Myhre Harry Øysæd Svein H. Jamtvedt Marit Kvalvåg Pettersen 《Polymer Engineering and Science》2012,52(9):2015-2024
Packaging material with optimal light barrier properties can prevent food quality deterioration. For dairy products, wavelength in the visible region between 400–450 nm and 600–650 nm should be blocked out due to the content of chlorophyll in dairy products. Six low density polyethylene blown films were formulated with the combination of four different pigments and additives: green, yellow, silver additive, and optical brightener, in addition to four reference samples. All films were transparent. Optical properties and light transmission were measured for each film, and microscopy analyses were used to investigate the surface topography. The sample containing high concentration of both green and yellow pigments had the lowest value in gloss and transmittance. This film blocked the light below 450 nm and transmitted 10% at 600–650 nm. Optical brightener had an effect only on visual appearance but not on light transmission properties. Samples containing silver additive were more intense green and gave a higher light transmission in blue region (380–500 nm) and lower in red region (600–700 nm) compared with samples without silver additive. These developed films can be applied in dairy products and other food products in the future. POLYM. ENG. SCI., 52:2015–2024, 2012. © 2012 Society of Plastics Engineers 相似文献
110.
Regular frankfurters treated with tofu powder had decreased fat with no significant differences in color, texture, or overall acceptability compared to a control by sensory analysis. Lean frankfurters with tofu powder had lower moisture and color, better texture, and overall acceptability with no flavor differences from controls. Except for fracturability, there were no differences in texture-related parameters by Texture Profile Analysis (TPA) between regular and control frankfurters but treated lean frankfurters had improved texture. Lean pork sausages treated with tofu powder were lower in fat, higher in protein, and moisture with no differences in sensory attributes compared to controls. 相似文献