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101.
T Tsukamoto H Kinoshita K Hirohashi S Kubo S Otani 《Canadian Metallurgical Quarterly》1997,44(15):744-750
BACKGROUND/AIM: There are various indices of liver regeneration, but no clinically useful index that reflects the current status of liver regeneration. We assayed human erythrocyte polyamine levels after partial hepatectomy to define the relationship between erythrocyte polyamine levels and liver regeneration. MATERIALS AND METHODS: Levels of human erythrocyte polyamines (putrescine, spermidine, and spermine) were assayed by high-pressure liquid chromatography in 91 patients after partial hepatectomy and in 13 patients after surgery other than partial hepatectomy (controls). Of the patients after partial hepatectomy, 37 underwent hepatectomy of 20% or more of the liver (group A), 27 underwent segmentectomy or subsegmentectomy of the liver amounting to less than 20% of the liver (group B), and 27 underwent an operation smaller in scale than sub-segmentectomy (group C). RESULTS: The greater the proportion of the liver resected, the greater was the percent increase. In groups A, B, and C, erythrocyte levels of spermidine and spermine increased after surgery compared with the base line, and were significantly higher at 7 or 14 days, decreasing later. The differences in spermidine among the three groups were significant. CONCLUSIONS: After partial hepatectomy, the erythrocyte polyamine levels, especially the level of spermidine, were related to the proportion of liver resected. They seemed to reflect the degree of liver regeneration. 相似文献
102.
T Tsukamoto T Fujioka T Yamauchi Y Mori I Nagakubo 《Canadian Metallurgical Quarterly》1997,88(8):746-751
The use of proxy respondents in surveys designed to provide population estimates of smoking prevalence offers an inexpensive way to obtain these data. The accuracy of this information is examined in analyzing data from tobacco use surveys of adults conducted in 22 North American communities as part of the National Cancer Institute's Community Intervention Trial for Smoking Cessation. Proxy-reported smoking status was obtained in a cross-sectional telephone survey conducted from August 1993 to January 1994 (n = 99,682). Self-reported smoking status was obtained from an in-depth interview of a sample of the respondents aged 25-64 years enumerated from the telephone survey (n = 31,417). Discrepancy rates were calculated by comparing the proxy-reported and self-reported smoking statuses of a given individual (n = 10,226). In both surveys, respondents were categorized as current smokers (those who currently smoke and have smoked at least 100 cigarettes in their lifetime), recent quitters (< or = 8 years since cessation), long-term quitters (> 8 years since cessation), and never smokers. The overall discrepancy rate between the self-report and the proxy report was 5.4%. Self-respondents who were black, Hispanic, Asian, recent quitters, or aged 25-34 years were more likely to have inconsistent proxy reports. The authors estimate that the screener interview underestimated the true smoking prevalence by 0.1% when they corrected for smoking status discrepancies. These results confirm that proxy-reported smoking status is an accurate and effective means to monitor populationwide smoking prevalence of adults. 相似文献
103.
Due to the recent popularization of mobile multimedia broadcasting, broadcasting continuous media data such as audio and video has attracted great deal of attention. In general continuous media data broadcasting, since clients have to wait to receive data before playing it, various schemes to reduce waiting time have been studied. Some reduce the waiting time by dividing the data into several segments and broadcasting preceding segments frequently with a single channel. However, by dividing the data into numerous segments and producing an effective broadcast schedule, the waiting time can be further reduced. In this paper, we propose a scheduling protocol to reduce waiting time with large-scale data segmentation. 相似文献
104.
Ishikura S. Kurumada M. Terano T. Yamagami Y. Kotani N. Satomi K. Nii K. Yabuuchi M. Tsukamoto Y. Ohbayashi S. Oashi T. Makino H. Shinohara H. Akamatsu H. 《Solid-State Circuits, IEEE Journal of》2008,43(4):938-945
We propose a new 2-port SRAM with a single read bit line (SRBL) eight transistors (8 T) memory cell for a 45 nm system-on-a-chip (SoC). Access time tends to be slower as a fabrication is scaled down because of threshold voltage (Vt) random variations. A divided read bit line scheme with shared local amplifier (DBSA) realizes fast access time without increasing area penalty. We also show an additional important issue of a simultaneous read and write (R/W) access at the same row by using DBSA with the SRBL-8T cell. A rise of the storage node causes misreading. A read end detecting replica circuit (RER) and a local read bit line dummy capacitance (LDC) are introduced to solve this issue. A 128 bit lines - 512 word lines 64 kb 2-port SRAM macro using these schemes was fabricated by a 45 nm bulk CMOS low-standby-power (LSTP) CMOS process technology [1]. The memory cell size is 0.597 mum2. This 2-port SRAM macro achieves 7 times faster access time without misreading. 相似文献
105.
Shigeru Yamada Yasuyoshi Kurokawa Shinsuke Miyajima Makoto Konagai 《Nanoscale research letters》2014,9(1):246
The solar cell structure of n-type poly-silicon/5-nm-diameter silicon nanocrystals embedded in an amorphous silicon oxycarbide matrix (30 layers)/p-type hydrogenated amorphous silicon/Al electrode was fabricated on a quartz substrate. An open-circuit voltage and a fill factor of 518 mV and 0.51 in the solar cell were obtained, respectively. The absorption edge of the solar cell was 1.49 eV, which corresponds to the optical bandgap of the silicon nanocrystal materials, suggesting that it is possible to fabricate the solar cells with silicon nanocrystal materials, whose bandgaps are wider than that of crystalline silicon.
PACS
85.35.Be; 84.60.Jt; 78.67.Bf 相似文献106.
Md.Mahbubul Alam ShigeruMatsuo KenbuTeramoto ToshiakiSetoguchi Heuy-Dong Kim 《热科学学报(英文版)》2006,15(3):213-219
A computational investigation has been conducted to determine the effectiveness of a passive control technique ofattenuating cavity-induced pressure oscillations in a confined two-dimensional supersonic flow.The passivecontrol technique is achieved by fitting two flat plates near the front wall of a square cavity at Mach number 1.83at the cavity entrance.The results showed that the flat plates attached near the front wall of the cavity,discouraged the formation of feedback loop which is widely believed to be the reason of cavity resonance.Theresultant amount of attenuation of pressure oscillations was also dependent on the length of the fiat plate used asan oscillation suppressor. 相似文献
107.
The time-dependent behavior of non-equilibrium condensation of moist air through a Ludwieg tube with a diaphragm downstream is investigated by using a computational fluid dynamics work. The two-dimensional, compressible, Navier-Stokes equations, fully coupled with the condensate droplet growth equations, are numerically solved by a third-order MUSCL type TVD finite-difference scheme with a second-order fractional time step. Baldwin-Lomax turbulence model is employed to close the governing equations. The present computations represent the experimental flows well. The results obtained show that for an initial relative humidity over 40 %, the periodic excursions of the condensation shock occurs in the Ludwieg tube, and the frequency increases with the initial relative humidity. It is also found that total pressure loss due to non-equilibrium condensation in the Ludwieg tube should not be ignored even for a very low initial relative humidity. Furthermore, the variations of condensation properties are also di 相似文献
108.
Matemu AO Nakamura K Kayahara H Murasawa H Katayama S Nakamura S 《Journal of food science》2011,76(6):M299-M304
Abstract: Peptide mixtures prepared from soybean β‐conglycinin (7S‐peptides) were acylated with saturated fatty acids of different chain length (6C‐18C) in order to improve their antiviral activity against Feline calicivirus (FCV) strain F9 which is a typical norovirus surrogate. Among the fatty acids varieties, it was revealed that 7S‐peptides acylated with myristic and palmitic acids potently inhibited FCV replication. Myristorylation and palmitoylation of 7S‐peptides kept host cells viability at 91.51% and 98.90%, respectively. The infectivity of FCV on Crandell–Reese feline kidney cells was further determined after exposure of initial titer of 106.47 TCID50/mL. Myristoylated and palmitoylated 7S‐peptides significantly (P < 0.006) reduced FCV infectivity as compared to native 7S‐peptides. Native 7S‐peptides showed 25% FCV inhibitory activity while myristoylated and palmitoylated 7S‐peptides exhibited 98.59% and 99.98% reduction in FCV infectivity, respectively. Myristoylated and palmitoylated 7S‐peptides demonstrated higher anti‐FCV activity in a wide range of concentration with complete reduction at 25 μg/mL. Surface hydrophobicity was significantly (P < 0.05) increased after attachment of long hydrocarbon fatty acids to 7S‐peptides as supported by changes in fluorescence intensity. Enzymatic hydrolysis together with acylation will give an insight into surface and physiological functional lipopeptides derived from soy β‐conglycinin. 相似文献
109.
We describe the electrochemical detection of DNA methylation through the direct oxidation of both 5-methylcytosine (mC) and cytosine (C) in 5'-CG-3' sequence (CpG) oligonucleotides using a sputtered nanocarbon film electrode after digesting a longer CpG oligonucleotide with endonuclease P1. Direct electrochemistry of the longer CpG oligonucleotides was insufficient for obtaining the oxidation currents of these bases because the CG rich sequence inhibited the direct oxidation of each base in the longer CpG oligonucleotides, owing to the conformational structure and its very low diffusion coefficient. To detect C methylation with better quantitativity and sensitivity in the relatively long CpG oligonucleotides, we successfully used an endonuclease P1 to digest the target CpG oligonucleotide and yield an identical mononucleotide 2'-deoxyribonucleoside 5'-monophosphate (5'-dNMP). Compared with results obtained without P1 treatment, we achieved 4.4 times higher sensitivity and a wider concentration range for mC detection with a resolution capable of detecting a subtle methylated cytosine difference in the CpG oligonucleotides (60mer). 相似文献
110.
Vincent Lijo Heuy Dong Kim Toshiaki Setoguchi Shigeru Matsuo 《Journal of Mechanical Science and Technology》2011,25(2):341-347
When sonic nozzles of significantly smaller diameter are used as standard flow meters, the critical backpressure ratio is
affected by the boundary layer at the nozzle throat. It is known that, as the flow pathway is complicated in actual valves,
the critical pressure ratio differs from the ideal value. However, the effect of the boundary layer thickness on choking criteria
is still controversial. Choking phenomenon in a sonic nozzle fitted with a straight circular pipe of variable length is investigated
numerically and the results are compared with experimental and theoretical ones. The results show that the actual critical
pressure ratio is less than the ideal value and it decreases with increase in pipe length. The effect of boundary layer thickness
on main flow Mach number is also made clear in this work. In addition, sonic conductance and pressure loss in actual viscous
flows computed are compared with the ISO 6358 standard. 相似文献