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1.
To study bone loss relationships to aging and menopause, cross-sectional bone mass measurements by digital image processing (DIP method), and menopause information collected by questionnaire, were analyzed on 291 women who live in Tsukude village. The results are as follows. 1) The mean DIP values (sigma GS/D, MCI) by age-stratified groups decrease with age after menopause. The rate of bone loss in sigma GS/D is almost constant, but in MCI it increases with aging. 2) In 30-year old and 40-year old age groups, the frequency distribution of DIP values is symmetrical and bell-shaped. But after the fifties the distribution is asymmetrical, with the mode of distribution deviated toward low bone mass. The change of mode with aging is larger than that of mean. This fact suggests that change of mean bone mass substantially underestimates actual bone loss from aging. 3) The change of the mean DIP values stratified by years elapsed since menopause is not especially large at start of menopause but becomes almost constant after menopause. DIP values reflect the bone loss from the aging rather than from menopause, and are beneficial to the study of bone loss in elderly women.  相似文献   
2.
The composites of polyacrylates and eutectic metal alloy composed by Bi, In, and Sn were prepared by mixing the metal and polymer above the melting point of the metal alloy (80 °C) with a homogenizer. Two melting peaks, which were assigned as the melting peak of the original metal alloy and that of the interfacial phase of the metal alloy interacting with polyacrylates (70 °C) by differential scanning calorimetry. Metal particles with the diameter of about 100 nm which were stabilized by the interfacial interaction with polyacrylates were observed by transmission electron microscopy. The melting peak at 70 °C was assigned as the melting peak of these small particles.  相似文献   
3.
The expression and function of the Fas-receptor (Fas-R) were examined in chronic lymphocytic leukaemia (CLL), hairy cell leukaemia-variant (HCL-v) and adult T-cell leukaemia (ATL). The expression of Fas-R in freshly isolated leukaemic cells was qualitatively and quantitatively different between each disease; faint in B-CLL, moderate in HCL-v and strong in ATL. Both full-length and alternatively spliced truncated forms of Fas mRNA were detected even in CLL B cells with faint to negative Fas-R, and Fas mRNA was also shown to be capable of increasing in vitro expression, i.e. the message was functional. In contrast, Fas-R expression on ATL cells was heterogenous and usually intense with a mean density approximately 3-fold higher than that of normal T cells. Fas-R was confirmed to have the potential function for anti-Fas monoclonal antibody-mediated cell death in vitro in Fas-R+ ATL cells. The expression level of Fas-R on the cells was higher in chronic than acute ATL (10,360 v 6260 antibody-binding capacity per cell, mFasABC; P<0.05) and was inversely correlated with serum LDH activity, suggesting that the strong Fas-R accounts for the slow progression of chronic ATL and the negative Fas-R protects from Fas-mediated cell death. These results show that Fas-R expression on leukaemic cells is valuable in their characterization and perhaps their function, and may contribute to the progression and immune evasion of malignant clones.  相似文献   
4.
This paper describes a silicon on insulator (SOI) DRAM which has a body bias controlling technique for high-speed circuit operation and a new type of redundancy for low standby power operation, aimed at high yield. The body bias controlling technique contributes to super-body synchronous sensing and body-bias controlled logic. The super-body synchronous sensing achieves 3.0 ns faster sensing than body synchronous sensing and the body-bias controlled logic realizes 8.0 ns faster peripheral logic operation compared with a conventional logic scheme, at 1.5 V in a 4 Gb-level SOI DRAM. The body-bias controlled logic also realizes a body-bias change current reduction of 1/20, compared with a bulk well-structure. A new type of redundancy that overcomes the standby current failure resulting from a wordline-bitline short is also discussed in respect of yield and area penalty  相似文献   
5.
Cross‐modal correspondences in the human sensory systems often appear for different levels of sensory inputs, such as colour and odour. However, whether there is hormonal modification of such colour‐odour correspondence has remained unclear. Here, we experimentally investigated the influence of hormonal changes in menopausal women by conducting evaluations of colour and odour impressions, matching tasks between colour and odour, and odor identification tasks, comparing two groups of women: premenopausal and postmenopausal. The results showed that both premenopausal and postmenopausal women had similar impressions and images of colours for odors, while postmenopausal women had significantly lower abilities of odor identification than premenopausal women. This suggested that the degree of conviction about an odor's identification might slightly affect the subjects’ impressions of odors and their corresponding colour choices. Menopause might not directly affect cognitive aspects regarding colour or odor, but might instead affect their perceptions.  相似文献   
6.
Women might experience modulation in their perception and cognition of colours and odours during the menstrual cycle, but how women's impressions of and correspondence between colours and odours differ according to the cycle changes remains unknown. Here, we experimentally examined women's performance of several tasks, including evaluation of impressions of colours and odours, matching/nonmatching of colours with odours, and identification of odours, comparing two phases: the beginning of menstruation and ovulation. The results showed that participants had similar impressions of colours and odours and made similar colour choices for odours in both the menstrual and ovulation phases, while “pleasant-unpleasant” impressions of colour and odour might vary according to the menstrual cycle. We found no significant differences in odour identification between the phases. The findings imply that hormonal changes during the menstrual cycle might affect “pleasant-unpleasant” impressions of colour and odour but not other features regarding impressions or crossmodal correspondence. In future studies, examination with a large number of participants is necessary.  相似文献   
7.
Women might have changes in perception and cognition of colours according to hormonal changes during the menstrual cycle. Colours are often associated with specific emotional facial expressions, but how these two factors interact with each other and differ according to the cycle has remained unclear. We investigated attentional interference between colours and emotional facial expressions for women in the menstrual compared to the ovulation phases by colour judgment based on the Stroop tasks. Participants identified the colours (either red, yellow, or blue) of three types of face stimuli (happy, neutral, or sad) and corresponding scrambled face stimuli by pressing buttons, and we recorded participants' reaction times. The results showed better performance in the menstrual phase than in the ovulation phase. An interference effect was not observed. However, in the scrambled face stimuli task, only the reaction time for happy scrambled face shape and red did not differ between the phases. Thus, participants might pay stronger attention to faces with colours in the menstrual phase than in the ovulation phase but weaker attention to scrambled face shapes in the menstrual phase.  相似文献   
8.
A phased array of surface coils was constructed for magnetic resonance imaging in three different regions in the brachial plexus. Four-coil subsets of the six-coil array were activated at any given time during imaging in three volunteers. An in vivo estimate of the signal-to-noise ratio (S/N) at three locations in the brachial plexus indicated that the phased-array coil provided a signal-to-noise ratio that was three to six times higher than that of the body coil.  相似文献   
9.
Dirac/Weyl semimetals hosting linearly dispersing bands have received recent attention for potential thermoelectric applications, since their ultrahigh-mobility carriers could generate large thermoelectric and Nernst power factors. To optimize these efficiencies, the Fermi energy needs to be chemically controlled in a wide range, which is generally difficult in bulk materials because of disorder effects from the substituted ions. Here it is shown that the Fermi energy is tunable across the Dirac point for layered magnet EuMnBi2 by partially substituting Gd3+ for Eu2+ in the insulating block layer, which dopes electrons into the Dirac fermion layer without degrading the mobility. Clear quantum oscillation observed even in the doped samples allows to quantitatively estimate the Fermi energy shift and optimize the power factor (exceeding 100 µ W K−2 cm−1 at low temperatures) in combination with the first-principles calculation. Furthermore, it is shown that Nernst signal steeply increases with decreasing carrier density beyond a simple theoretical prediction, which likely originates from the field-induced gap reduction of the Dirac band due to the exchange interaction with the Eu moments. Thus, the magnetic block layer provides high controllability for the Dirac fermions in EuMnBi2, which would make this series of materials an appealing platform for novel transport phenomena.  相似文献   
10.
Although numerous experiments revealed an essential role of a lipid mediator, sphingosine-1-phosphate (S1P), in breast cancer (BC) progression, the clinical significance of S1P remains unclear due to the difficulty of measuring lipids in patients. The aim of this study was to determine the plasma concentration of S1P in estrogen receptor (ER)-positive BC patients, as well as to investigate its clinical significance. We further explored the possibility of a treatment strategy targeting S1P in ER-positive BC patients by examining the effect of FTY720, a functional antagonist of S1P receptors, on hormone therapy-resistant cells. Plasma S1P levels were significantly higher in patients negative for progesterone receptor (PgR) expression than in those positive for expression (p = 0.003). Plasma S1P levels were also significantly higher in patients with larger tumor size (p = 0.012), lymph node metastasis (p = 0.014), and advanced cancer stage (p = 0.003), suggesting that higher levels of plasma S1P are associated with cancer progression. FTY720 suppressed the viability of not only wildtype MCF-7 cells, but also hormone therapy-resistant MCF-7 cells. Targeting S1P signaling in ER-positive BC appears to be a possible new treatment strategy, even for hormone therapy-resistant patients.  相似文献   
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