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1.
Fetics B.J. Wong E.Y. Murabayashi T. Nelson G.S. Cohen M.-M. Rochitte C.E. Weiss J.L. Kass D.A. Nevo E. 《IEEE transactions on medical imaging》2001,20(11):1123-1130
BACKGROUND: Although there have been recent advances in echocardiography, many studies remain suboptimal due to poor image quality and unclear blood-myocardium border. We developed a novel image processing technique, cardiac variability imaging (CVI), based on the variance of pixel intensity values during passage of ultrasound microbubble contrast into the left ventricle chamber, with the aim of enhancing endocardial border delineation and image quality. METHODS AND RESULTS: CVI analysis was performed on simulated data to test and verify the mechanism of image enhancement. Then CVI analysis was applied to echocardiographic images obtained in two different clinical studies, and still images were interpreted by expert reviewers. In the first study (N = 15), using contrast agent EchoGen, the number of observable wall segments in end-diastolic images, for example, was significantly increased by CVI (4.93) as compared to precontrast (3.28) and contrast images (3.36), P < 0.001 for both comparisons to CVI. In the second study (N = 8), using contrast agent Optison, interobserver variability of manually traced end-diastolic volumes was significantly decreased using CVI (22.3 ml) as compared to precontrast (63.4) and contrast images (49.0), P < 0.01 for both comparisons to CVI. CONCLUSION: CVI can substantially enhance endocardial border delineation and improve echocardiographic image quality and image interpretation. 相似文献
2.
Murabayashi F. Hotta T. Tanaka S. Yamauchi T. Yamada H. Nakano T. Kobayashi Y. Bandoh T. 《Solid-State Circuits, IEEE Journal of》1994,29(3):298-302
This paper describes 3.3-V BiCMOS circuit techniques for a 120-MHz RISC microprocessor. The processor is implemented in a 0.5-μm BiCMOS technology with 4-metal-layer structure. The chip includes a 240 MFLOPS fully pipelined 64-b floating point datapath, a 240-MIPS integer datapath, and 24 KB cache, and contains 2.8 million transistors. The processor executes up to four operations at 120 MHz and dissipates 17 W. Novel BiCMOS circuits, such as a 0.6-ns single-ended common base sense amplifier, a 0.46-ns 22-b comparator, and a 0.7-ns path logic adder are applied to the processor. The processor with the proposed BiCMOS circuits has a 11%-47% shorter delay time advantage over a CMOS microprocessor 相似文献
3.
A Maruyama K Murabayashi M Hayashi H Nakano S Isaji S Uehara T Kusuda S Miyahara A Kondo H Nakano T Yabana 《Canadian Metallurgical Quarterly》1998,28(12):1319-1322
We report herein the unusual case of a 66-year-old woman found to have adenocarcinoma arising in a tailgut cyst. The patient had been observed for 6 months following the discovery of a presacral cystic mass measuring 10 x 9 cm for which she had refused surgery. The serum tumor marker, carcinoembryonic antigen, became slightly elevated, and diagnostic imaging distinctly revealed a tumorous lesion with papillary projection into the cyst lumen. The cystic mass was then excised through the transsacral approach. The pathological findings were compatible with moderately differentiated adenocarcinoma arising in a tailgut cyst. This entity is extremely rare, and only six cases, including our own, have been reported in the English literature. Early complete excision is advised because it is almost impossible to determine for certain whether presacral cystic masses are benign or malignant prior to surgery. 相似文献
4.
Y Ikeura Y Ishichi T Tanaka A Fujishima M Murabayashi M Kawada T Ishimaru I Kamo T Doi H Natsugari 《Canadian Metallurgical Quarterly》1998,41(22):4232-4239
A potent and orally active NK1 antagonist, trans-N-[3, 5-bis(trifluoromethyl)benzyl]-7,8-dihydro-N, 7-dimethyl-5-(4-methylphenyl)-8-oxo-1,7-naphthyridine-6-carboxamide (1t), was shown to exist as a mixture of separable and stable (R)- and (S)-atropisomers (1t-A and 1t-B) originating from the restricted rotation around the -C(6)-C(=O)- bond; the antagonistic activities of 1t-A were ca. 6-13-fold higher than those of 1t-B. Analogues of 1t (3), which have (S)- and (R)-methyl groups at the benzylic methylene portion of 1t, were prepared and separated into the diastereomeric atropisomers, 3a-A, 3a-B and 3b-A, 3b-B, in enantiomerically pure forms. Among the four isomers of 3, the (aR, S)-enantiomer (3a-A) exhibited the most potent antagonistic activities with an IC50 value of 0.80 nM (in vitro inhibition of [125I]BH-SP binding in human IM-9 cells) and ED50 values of 9.3 micrograms/kg (iv) and 67.7 micrograms/kg (po) (in vivo inhibition of capsaicin-induced plasma extravasation in guinea pig trachea), while the activity of the (aS,R)-enantiomer (3b-B) was the weakest with an IC50 value of 620 nM. The structure-activity relationships in this series of antagonists indicate that the (R)-configuration at the axial bond and the stacking (or stacking-like) conformation between the two phenyl rings as shown in 1t-A and 3a-A are essential for high-affinity binding and suggest that the amide moiety functions as a hydrogen bond acceptor in the interaction with the receptor. 相似文献
5.
The polarimetric interference pattern on the surface of single-mode planar waveguides made by potassium ion exchange in soda-lime glass substrates can be observed through a 45 degrees analyzer, which allows for the high-precision measurement of the modal birefringence of samples in a wide range of 0 to 5 x 10(-4). Using this method, believed to be new, we investigated the effects of exchange temperature and time on the modal birefringence of single-mode potassium ion-exchanged waveguides. The modal birefringence profile was achieved by measurement of the variation of the phase difference between the TE(0) and the TM(0) modes with hydrofluoric-acid-etching depth of the sample. 相似文献
6.
A new polarimetric interferometer has been developed on the basis of the phase difference between transverse electric (TE)0 and transverse magnetic (TM)0 modes in a composite optical waveguide (OWG). The composite OWG consists of a single-mode potassium ion-exchanged planar waveguide overlaid with a high-index thin film that has two tapered ends and supports only the TE0 mode. Applying tapered velocity coupling theory, we found that the TE0 and TM0 modes coexisting in the potassium ion-exchanged layer were separated in the thin film region of the composite OWG: the TE0 mode was coupled into the thin film while the TM0 mode was confined in the potassium ion-exchanged layer. Interference occurs between TE- and TM-polarized output components when a single output beam is passed through a 45°-polarized analyzer. The phase difference φ between both orthogonal output components is very sensitive to the superstrate index nc in the thin film region. Our experimental results indicate that a slight change of Δnc=3.71×10-6 results in the phase-difference variation of Δφ=1° for a 5-mm-long TiO 2/K+ composite OWG with a 34-nm-thick TiO2 film. Such a simple polarimetric interferometer can be applied to chemical or biological sensors by modifying the upper film surface of the composite OWG with a chemically or biologically active substance 相似文献
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8.
Treatment of 2,4-D polluted waters with photocatalysis leads to the buildup of high concentrations of the long living intermediate 2,4-DCP. A new approach using a combination of ozonolysis and photocatalysis gave better degradation results with lower intermediate concentrations. The advantages of photocatalysis giving a constant decline in TOC and of ozonolysis giving no buildup of high intermediate concentrations were combined. Degradation data of 2,4-D for photocatalysis, ozonolysis and the combination of both for different pH ranges are given. Data on the main intermediate 2,4-DCP are given for the three different approaches. 相似文献
9.
Saito H Murabayashi S Mitamura Y Taguchi T 《Journal of materials science. Materials in medicine》2008,19(3):1297-1305
We have developed a naturally-derived crosslinker named malic acid derivative (MAD). In the present study, we prepared alkali-treated
collagen (AlCol) gels with different crosslinkers including MAD and commercially available crosslinkers such as 1-ethyl-3-(3(′-dimethylaminopropyl)
carbodiimide (EDC) and glutaraldehyde (GA). There are named as AlCol-MAD, AlCol-EDC, and AlCol-GA. We then compared their
physicochemical properties. The residual amino groups in AlCol-MAD were not detected at MAD concentrations higher than 30 mM.
On the other hand, the residual amino groups in AlCol-EDC and AlCol-GA were detected at crosslinker concentrations of 30 mM.
The swelling ratios of AlCol-MAD, AlCol-EDC, and AlCol-GA decreased with increasing crosslinker concentration. Enzymatic degradation
rate of AlCol-GA was slower than that of AlCol-MAD and AlCol-EDC. The cytotoxicity of MAD was clearly lower than that of EDC
and GA. The number of adhered L929 on AlCol-MAD was higher than on AlCol-EDC and AlCol-GA after incubation for 1 day. After
the culture for 3 and 7 days, excellent growth of L929 was observed on AlCol-MAD. These results suggested that MAD was excellent
crosslinker for the reactivity with amino groups and cytocompatibility. Therefore, the resulting AlCol-MAD has potential for
various biomedical applications like tissue engineering scaffolds and carrier for drug delivery systems. 相似文献
10.
Murabayashi F. Yamauchi T. Yamada H. Nishiyama T. Shimamura K. Tanaka S. Hotta T. Shimizu T. Sawamoto H. 《Solid-State Circuits, IEEE Journal of》1996,31(7):972-980
Novel 2.5 V CMOS circuit techniques including a noise tolerant precharge (NTP) circuit and a leakless buffer circuit are applied to a floating point macrocell for a 200 MHz superscalar RISC processor. The NTP circuit has two advantages: high noise immunity and high speed. Floating point operations can be executed in a two cycle latency using the high speed NTP circuit. The leakless buffer circuit with NMOS transmission gate in 128 floating point registers makes possible both high integration and low power dissipation, since the circuit causes no leak current without precharging the number of read lines. The processor makes use of 0.3 μm CMOS technology with a 2.5 V power supply and four metal layers. The floating point macrocell has 380 thousand transistors and dissipates 350 mW at 200 MHz. The peak performance of the floating point macrocell is 400 MFLOPS 相似文献