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181.
何谓按摩? 按摩就是用手或借助器械完成的特种手法(如推摩、挤压等)对人体产生的一种定量力学作用。按摩是在神经反射、体液和力学作用下,在人体各组织和器官中产生的复杂过程为基础的。神经反射机制的实质在于,按摩时刺激位于皮下的无数各种各样的神经末梢(外感受器);位于腱、韧带、筋膜、肌肉中的本体感受器;位于管脉中的血管感受器和位于内脏器官中的内感受器。所有这些感受器受到刺激时产生的冲动流就引起机体全面的复杂 相似文献
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Méndez A Pérez C Montañéz JC Martínez G Aguilar CN 《Journal of Zhejiang University. Science. B》2011,12(12):961-968
The combined effects of pH and temperature on red pigment production and fungal morphology were evaluated in a submerged culture
of Penicillium purpurogenum GH2, using Czapek-Dox media with d-xylose as a carbon source. An experimental design with a factorial fix was used: three pH values (5, 7, and 9) and two temperature
levels (24 and 34 °C) were evaluated. The highest production of red pigment (2.46 g/L) was reached with a pH value of 5 and
a temperature of 24 °C. Biomass and red pigment production were not directly associated. This study demonstrates that P. purpurogenum GH2 produces a pigment of potential interest to the food industry. It also shows the feasibility of producing and obtaining
natural water-soluble pigments for potential use in food industries. A strong combined effect (p<0.05) of pH and temperature was associated with maximal red pigment production (2.46 g/L). 相似文献
184.
Akinboro A Mohamed KB Asmawi MZ Sulaiman SF Sofiman OA 《Journal of Zhejiang University. Science. B》2011,12(11):915-922
In this study, freeze-dried water extract from the leaves of Myristica fragrans (Houtt.) was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its combination with cyclophosphamide (CP) (50 mg/kg) were separately dissolved
in tap water at 500, 1000, 2000, and 4000 mg/kg. Onions (A. cepa) were suspended in the solutions and controls for 48 h in the dark. Root tips were prepared for microscopic evaluation. 2,2-Diphenyl-1-picrylhydrazyl
(DPPH) free radicals’ scavenging power of the extract was tested using butylated hydroxyanisole (BHA) and butylated hydroxytoluene
(BHT) as standards. Water extract of Myristica fragrans scavenged free radicals better than BHA, but worse than BHT. The extract alone, as well as in combination with CP suppressed
cell division, and induced chromosomal aberrations that were insignificantly different from the negative control (P≤0.05). However, cytotoxic and mutagenic actions of CP were considerably suppressed. The observed effects on cell division
and chromosomes of A. cepa may be principally connected to the antioxidant properties of the extract. The obtained results suggest mitodepressive and
antimutagenic potentials of water extract of the leaves of M. fragrans as desirable properties of a promising anticancer agent. 相似文献
185.
Science education in the United States will increasingly be driven by testing and accountability requirements, such as those mandated by the No Child Left Behind Act, which rely heavily on learning outcomes, or "standards," that are currently developed on a state-by-state basis. Those standards, in turn, drive curriculum and instruction. Given the importance of standards to teaching and learning, we investigated the quality of life sciences/biology standards with respect to genetics for all 50 states and the District of Columbia, using core concepts developed by the American Society of Human Genetics as normative benchmarks. Our results indicate that the states' genetics standards, in general, are poor, with more than 85% of the states receiving overall scores of Inadequate. In particular, the standards in virtually every state have failed to keep pace with changes in the discipline as it has become genomic in scope, omitting concepts related to genetic complexity, the importance of environment to phenotypic variation, differential gene expression, and the differences between inherited and somatic genetic disease. Clearer, more comprehensive genetics standards are likely to benefit genetics instruction and learning, help prepare future genetics researchers, and contribute to the genetic literacy of the U.S. citizenry. 相似文献
186.
在日内瓦的普伦·迪尤·帕勒地区,有一家俄国侨民经营的小咖啡馆,政治流亡者们通常在这家咖啡馆举行集会。在咖啡馆或晚会上,我曾不止一次地看到过列宁下象棋。在同志们中间,弗拉基米尔·伊里奇~①被认为是个棋艺最高超的棋手,大家都把赢下他引以为很大的荣誉。每当弗拉基米尔·伊里奇同别人下象棋的时 相似文献
187.
那是一个夏日的夜晚,我和女儿麦琪在月光下的佛罗里达海岸漫步。大约快10点了,白天那些日光浴的人、冲浪的人都已经离开了,海岸上只有我们母女在安静地走着。突然,我看见不远处有一只海龟正在慢吞吞地爬出海水。它湿漉漉的背有一米多长,在月光下熠(yi)熠闪光。它左右环顾,然后把头埋进沙里,好像是在品尝沙子的味道、感觉沙子的温度。它记得这片海滩吗?科学家们认为母海龟只会选择它出生的海滩来产卵。这只海龟,也是在海中游荡多年之后, 相似文献
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分别利用CATIAV5和ANSYSWorkbench软件对行星架进行了三维实体建模与线性静态结构分析,通过线性静态分析计算出了行星架的受力和变形情况,以及工作循环次数和工作安全系数,为行星架的结构设计提供了可靠地参考依据。 相似文献
190.