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Trent D Lund Timothy W West Lilyan Y Tian Lihong H Bu Daniel L Simmons Kenneth DR Setchell Herman Adlercreutz Edwin D Lephart 《BMC neuroscience》2001,2(1):20-13
Background
In learning and memory tasks, requiring visual spatial memory (VSM), males exhibit superior performance to females (a difference attributed to the hormonal influence of estrogen). This study examined the influence of phytoestrogens (estrogen-like plant compounds) on VSM, utilizing radial arm-maze methods to examine varying aspects of memory. Additionally, brain phytoestrogen, calbindin (CALB), and cyclooxygenase-2 (COX-2) levels were determined. 相似文献2.
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DR.G. Domairry A. Mohsenzadeh M. Famouri 《Communications in Nonlinear Science & Numerical Simulation》2009,14(1):85-95
In this paper Jeffery–Hamel flow has been studied and its nonlinear ordinary differential equation has been solved through homotopy analysis method (HAM). The obtained solution in comparison with the numerical ones represents a remarkable accuracy. The results also indicate that HAM can provide us with a convenient way to control and adjust the convergence region. 相似文献
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Crystal Blake Kimberly M Fabick Kenneth DR Setchell Trent D Lund Edwin D Lephart 《BMC neuroscience》2011,12(1):28
Background
Soy-derived isoflavones potentially protect against obesity and depression. In five different studies we examined the influence of soy-containing diets or equol injections on depression, serotonin levels, body weight gain (BW) and white adipose tissue (WAT) deposition in female Long-Evans rats at various stages of life [rats were intact, ovariectomized or experienced natural ovarian failure (NOF)]. 相似文献6.
Nettles SM Matos K Burkhardt ER Rouda DR Corella JA 《The Journal of organic chemistry》2002,67(9):2970-2976
When stabilized BH(3-)THF (BTHF) was added to a mixture of ketone and tetrahydro-1-methyl-3,3-diphenyl-1H,3H-pyrrolo[1,2-c][1,3,2]oxazaborole (MeCBS-ozaxaborolidine, MeCBS) catalyst 1, low enantioselectivities resulted. Several relative rate experiments showed that a borohydride species in BTHF catalyzed the nonselective borane reduction of ketones, effectively competing with enantioselective MeCBS reduction of ketones, lowering the overall selectivity of the reaction. Improved enantioselectivities in the reaction are obtained by reversing the mode of addition (ketone to BTHF and catalyst), lowering the concentration of NaBH(4) stabilizer in the BTHF solution (87-95% ee) and increasing the concentration or addition rate of BTHF. Decreased reaction temperature and increased catalyst loading only slightly improved the selectivity of the reaction. Upon reaction parameter optimization, simultaneous addition of substrate and BTHF to MeCBS catalyst stabilizer resulted in the highest overall enantioselectivities (96% ee) and diminished the effect of the borohydride. Alternatively, the addition of Lewis acids such as BF(3-)THF to the reaction mixture effectively destroyed the NaBH(4) stabilizer in BTHF solutions, restoring the enantioselectivity to acceptable levels. 相似文献
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DR. E. W. J. Mitchell 《Contemporary Physics》2013,54(3):217-222
The accurate measurement of the thermal conductivity of metals still poses considerable experimental difficulty. The reasons for this, and the main ways in which the problem has been approached, are summarized. A detailed examination of the development in technique and methods of measurement shows that while most of the steady-state methods introduced over 50 years ago are still being improved, the emphasis in the last few years has been on the development of methods which give more rapid results, particularly at high temperatures. 相似文献
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DR Matravers 《Contemporary Physics》2013,54(3):251-254
The history of absolute measurements of gravity is mentioned and the reasons for making absolute measurements are indicated. The principles and main advantages and difficulties of the main method—reversible pendulum, free fall, symmetrical free motion—are discussed and examples of each method are described. Problems of comparison of different determinations and of estimating systematic errors are considered. 相似文献
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