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1.
We performed a cross-sectional survey of stroke and acute myocardial infarction (AMI) in Okinawa, Japan with a census population of about 1.2 million. A total of 3,644 cases of first-ever stroke and 898 cases of initial acute myocardial infarction (AMI) were detected. The age-adjusted annual incidence rate for stroke was 105 per 100,000 standard population of Japan, and that of AMI was 26. The case-fatality rate of stroke within 28 days of onset was 12.8%, and that of AMI was 22.2%. Of the stroke cases, 51.4% were diagnosed as brain infarction, 38.7% as brain hemorrhage, and 9.3% as subarachnoid hemorrhage. The diagnosis of stroke subtypes were confirmed by computed tomography or magnetic resonance imaging in 98.4% of all stroke cases. In Okinawa, the incidence rate of AMI was still considerably lower than that in the Western population, and the rate of stroke was similar to that in the Western population.  相似文献   
2.
The effect of plasma elongation on the second‐stable spherical tokamak (ST) was numerically studied using the experimentally measured pressure and current profiles of ultrahigh‐beta STs. The maximum beta of ST over 50% was obtained in the TS‐3 ST/CT experiment by applying an external toroidal field to an FRC. It was found that the marginal beta for the ballooning instability increased with the plasma elongation κ of ST. The elongated STs with κ > 2 have the magnetic shear (S)–pressure gradient (α) profiles located in the second‐stable regime for the ballooning mode and the stability margin increased with κ. The close relation between the absolute minimum‐B profile and the second stability was documented. The effect of elongation on maximum beta was observed to saturate when κ exceed 3, indicating that the optimized elongation for high‐beta STs is located around 2 < κ < 3. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(4): 1–6, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20132  相似文献   
3.
The present study aimed to examine the effect of melatonin on naloxone-induced luteinizing hormone (LH) secretion in ovariectomized estrogen-primed rats. A single intracerebroventricular (i.c.v.) injection of naloxone (mu opioid receptor blocker, 15 micrograms) or an intravenous (i.v.) injection of LH-releasing hormone (LHRH, 50 ng/kg) elicited a transient and significant increase in the serum LH concentration within 10 min. While an i.c.v. injection of 100 ng melatonin by itself did not change the basal LH release, it almost completely inhibited the naloxone-induced LH release. Melatonin (10 ng) also significantly reduced the effect of naloxone. However, an i.c.v. injection of 100 ng melatonin did not affect the LHRH-induced LH release. In separate experiments, the effect of melatonin on naloxone-induced pulsatile LH secretion was studied in estrogen-treated rats. A continuous i.v. infusion of naloxone (20 mg/kg/h) induced LH pulses in rats treated i.c.v. with saline. An i.c.v. administration of 100 ng melatonin, which by itself did not affect basal LH secretion, significantly reduced the frequency, but not the amplitude, of LH pulses induced by the naloxone infusion. These results show that melatonin has a suprapituitary site of action to inhibit naloxone-induced LH release, and suggest that melatonin has an effect in inhibiting the activity of the hypothalamic LHRH pulse generator, either directly or indirectly, in female rats.  相似文献   
4.
An instantaneous response CMOS optical-receiver IC is described with wide input dynamic range and high sensitivity. In a TCM (time compression multiplexing)-TDMA (time division multiple access) fiber-optic subscriber system, a receiver should be able to handle burst-data packets with different amplitude. This requires quick response and a wide dynamic range. Instantaneous response is achieved with a new feed-forward auto-bias adjustment technique. In addition, multistaged offset compensation provides a wide dynamic range without any external elements and adjustments. Using these design techniques, an optical receiver IC was fabricated in a standard 0.8-μm CMOS technology. The receiver has a wide dynamic range of more than 25 dB for burst-mode optical input at 29 Mb/s. It has high transimpedance gain of 150 dBΩ and high sensitivity of -42 dBm with stable operation for FET threshold voltage and power supply voltage fluctuation  相似文献   
5.
Triple-negative breast cancer (TNBC) has the poorest prognosis of all breast cancer subtypes. Recently, the activation of NF-κB, which is involved in the growth and survival of malignant tumors, has been demonstrated in TNBC, suggesting that NF-κB may serve as a new therapeutic target. In the present study, we examined whether dimethyl fumarate (DMF), an NF-κB inhibitor, induces apoptosis in TNBC cells and enhances the apoptosis-inducing effect of paclitaxel and adriamycin. Cell survival was analyzed by the trypan blue assay and apoptosis assay. Protein detection was examined by immunoblotting. The activation of NF-κB p65 was correlated with poor prognosis in patients with TNBC. DMF induced apoptosis in MDA-MB-231 and BT-549 cells at concentrations that were non-cytotoxic to the normal mammary cell line MCF-10A. Furthermore, DMF inhibited NF-κB nuclear translocation and Survivin, XIAP, Bcl-xL, and Bcl-2 expression in MDA-MB-231 and BT-549 cells. Moreover, DMF enhanced the apoptosis-inducing effect of paclitaxel and adriamycin in MDA-MB-231 cells. These findings suggest that DMF may be an effective therapeutic agent for the treatment of TNBC, in which NF-κB is constitutively active. DMF may also be useful as an adjuvant therapy to conventional anticancer drugs.  相似文献   
6.
We present numerically verified a posteriori estimates of the norms of inverse operators for linear parabolic differential equations. In case that the corresponding elliptic operator is not coercive, existing methods for a priori estimates of the inverse operators are not accurate and, usually, exponentially increase in time variable. We propose a new technique for obtaining the estimates of the inverse operator by using the finite dimensional approximation and error estimates. It enables us to obtain very sharp bounds compared with a priori estimates. We will give some numerical examples which confirm the actual effectiveness of our method.  相似文献   
7.
Thermal cis–trans conversion has been examined in oligothiophene single molecules encapsulated in the molecular vessels of cyclodextrin and Na-mordenite. At high temperatures, optical absorption intensities are enhanced in bithiophene, terthiophene and quinquethiophene, while the intensity of quarterthiophene is temperature independent. Optical absorption comes from uncompensated transition dipole moment due to the thermal torsion between cis and trans forms.  相似文献   
8.
Trehalose was compared with glucose in its use as an embedding medium for the preparation of two-dimensional crystals for electron crystallographic structure analysis. Purple membranes (two-dimensional crystals of bacteriorhodopsin) embedded in either sugar were studied in a 'partially hydrated' state as well as after 'drying' of the specimen. Diffraction patterns of the four conditions, all showing spots to a resolution better than 3.0 A, were analysed and merged. In the case of glucose embedded specimens, the merging R-factor obtained from the diffraction patterns of dried specimens was significantly better than the one obtained from partially hydrated specimens. In the case of trehalose embedding, the merging R-factor for partially hydrated specimens was significantly better than the dried one. The trehalose embedded, partially hydrated specimens gave the best merging R-factor in all four cases.  相似文献   
9.
Micro inspection robot for 1-in pipes   总被引:6,自引:0,他引:6  
A micro inspection robot for 1-in pipes has been developed. The robot is 23 mm in diameter and 110 mm in length and is equipped with a high-quality micro charge-coupled device (CCD) camera and a dual hand for manipulating small objects in pipes. It can travel through both vertical pipes and curved sections, making possible inspections that would be difficult with conventional endoscopes. Its rate of travel is 6 mm/s and it has a load-pulling power of 1 N. To realize this microrobot, the authors have specially designed and developed several micro devices and micromechanisms: a novel micromechanism called a planetary wheel mechanism for robot drive; a micro electromagnetic motor with a micro planetary reduction gear to drive the planetary wheel mechanism; a micro pneumatic rubber actuator that acts as a hand; a micro CCD camera with high resolution; and a pneumatic wobble motor for rotating the camera and hands. In the paper, the design and performance of these micro devices are reported, the performance of the robot as a whole is described, and an application example is given  相似文献   
10.
Orthogonal frequency division multiplexing (OFDM) is robust against multi-path interference due to using a lot of low symbol rate sub-carriers. In order to mitigate the degradation due to multi-path interference, guard time interval (GI) is inserted into each OFDM symbol. However, redundant allocation to GI leads to loss of effective transmission power. We propose the Block-OFDM which can reduce the GI overhead ratio per frame compared with conventional OFDM. In Block-OFDM system frequency domain equalization (FDE) is carried out in order to remove multi-path interference. We evaluated Block-OFDM performance in a frequency selective fading channel and compared with that of conventional OFDM. Ryohei Kimura received his B.E. and M.S degrees in communications engineering form Tohoku University, Sendai, Japan, in 2001 and 2003, respectively. In 2003, he joined Panasonic Mobile Communications Co., Ltd. His current research interests include such mobile communication technologies as OFDM and MIMO (MLD), and the like. Akiyoshi Monma received his B.E. in communications engineering form Tohoku University, Sendai, Japan, in 1998. In 1998, he joined Panasonic Mobile Communications Sendai R&D Lab. Co., Ltd. His current research interests include such mobile communication technologies as OFDM and PAPR reduction, and the like. Jinsong Duan received his B.E. and M.S. from Changsha Institute of Technology, China in 1987 and 1990. He received his Ph.D. from Osaka City University, Japan in 2000. From 2000–2003 he was with Mitsubishi Electric Corporation, where he engaged in research and development of WCDMA systems. From 2003, he joined Panasonic Mobile Communications Co., Ltd. His current interests include such mobile communication technologies as OFDM, MIMO, link adaptation, scheduling, and TDMA/FDMA/CDMA systems. Mitsuru Uesugi received his B.E. degree from Waseda University in 1986 and received his Ph.D degree from Tohoku University in 2004, respectively. He is a general manager in the Mobile Communication Technology Development Center of Panasonic Mobile Communications Co., Ltd. His current research interests include such mobile communication technologies as equalization, interference cancellation, modulation method, and the like.  相似文献   
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