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排序方式: 共有1582条查询结果,搜索用时 31 毫秒
991.
992.
J Furuse M Iwasaki M Yoshino M Konishi N Kawano T Kinoshita M Ryu M Satake N Moriyama 《Canadian Metallurgical Quarterly》1997,204(3):787-790
PURPOSE: To evaluate transcatheter arterial embolization in patients with hepatocellular carcinoma, portal vein tumor thrombus, and arterioportal shunts. MATERIALS AND METHODS: Ten patients with hepatocellular carcinoma, portal vein tumor thrombus, and severe arterioportal shunting were identified; in these patients, portal blood flow before embolization was hepatofugal. Embolization of arterioportal shunts was performed with steel coils that were introduced through a catheter during arteriography. After embolization, changes in portal hemodynamics and clinical signs and performance status of patients were evaluated; survival rates of patients with and patients without severe arterioportal shunting were compared. RESULTS: In all patients after embolization, angiography showed resolution of arterioportal shunting, and portography showed hepatopetal blood flow in the portal vein trunk. After embolization, performance status of five patients with initial scores of 2 or 3 improved. Ascites resolved in four patients and improved in four patients. One patient died of hepatic failure caused by rupture of esophageal varices 7 days after embolization. Median survival was 4.3 months, and the 6-month and 1-year survival rates were 45% and 12%, respectively. There were no significant differences between survival rates in patients with and patients without severe arterioportal shunting. CONCLUSION: Transcatheter arterial embolization of arterioportal shunts is a useful treatment for improving quality of life in patients with hepatocellular carcinoma. 相似文献
993.
994.
Ji-Guang Li † Chengchun Tang Di Li Hajime Haneda Takamasa Ishigaki 《Journal of the American Ceramic Society》2004,87(7):1358-1361
Phase-pure brookite of high crystallinity, which was classically obtained via hydrothermal treatment, has been synthesized under ambient pressure at 70°C via reacting a mixed solution of urea and titanium (III) chloride (instead of the widely used titanium (IV) compounds). The resultant particles are monodispersed spheres (∼154 nm) composed of brookite nanocrystals (∼25 nm), which are stable in terms of phase purity and morphology up to ∼500°C, above which a direct transition to rutile occurred. The as-made powder has a high specific surface area of ∼41.2 m2 /g, which rapidly decreased to ∼9.7 m2 /g after transforming to rutile at 700°C. The brookite powder shows good catalytic property for the decomposition of acetaldehyde under UV radiation. 相似文献
995.
Sumita M. Sakiyama S. Kinoshita M. Araki Y. Ikeda Y. Fukuoka K. 《Solid-State Circuits, IEEE Journal of》2005,40(1):60-66
There remains a need to improve sub-1-V CMOS VLSIs with respect to variation in transistor behavior. In this paper, to minimize variation in delay and the noise margin of the circuits in processors, we propose several mixed body bias techniques using body bias generation circuits. In these circuits, either the saturation region of the current between source and drain (I/sub ds/) or the threshold voltage (V/sub t/) of PMOS/NMOS is permanently fixed, regardless of temperature range or variation in process. A test chip that featured these body bias generation circuits was fabricated using a 130-nm CMOS process with a triple-well structure. The mixed body bias techniques which keep the I/sub ds/ of the MOS in the decoder and I/O circuits of a register file fixed and maintain the V/sub t/ of the MOS in both the memory cell and domino circuits of the register file fixed resulted in positive temperature dependence of delay from -40 /spl deg/C to 125 /spl deg/C, 85% reduction of the delay variation compared with normal body bias (NBB) at V/sub DD/ = 0.8 V. In addition, the results using these techniques show a 100-mV improvement in lower operating voltage compared with NBB at -40 /spl deg/C on a 4-kb SRAM. 相似文献
996.
997.
Y Suzuki R Ohkura S Sugiura R Yasuda K Kinoshita M Tanokura K Sutoh 《Canadian Metallurgical Quarterly》1997,234(3):701-706
The insulin receptor gene is induced 8 to 10-fold during adipocyte differentiation. Plasmids containing the promoter, exon 1 and a portion of the first intron from either the mouse or human gene are able to modulate the expression of an insulin receptor/CAT gene 3 to 7-fold during differentiation. We have shown that several nuclear proteins from both preadipocyte and adipocyte nuclear extracts bind to two discrete sites within a 278-bp region in the 5' end of the first intron. Sequence comparison between the first intron of the human gene and the mouse gene shows two regions of sequence identity which correspond to the protein binding regions detected by DNase footprinting. One of these sites binds proteins that are enriched in adipocyte nuclear extracts and can be competed by adipose regulatory element, ARE6. 相似文献
998.
A simple, fast, reliable, and specific immunoassay has been developed to detect and measure AD7C-NTP, a biochemical marker for Alzheimer's disease, in cerebrospinal fluid (CSF). This assay, called the AD7C Test, is an enzyme-linked sandwich immunoassay (ELSIA) using 96 well microtiter plates. The plate surface is coated with a monoclonal antibody (N3I4) which has a high affinity and specificity for AD7C-NTP, capturing it effectively from CSF samples. The detection was achieved using a polyclonal antibody (ADRI). Both N3I4 and ADRI were generated using recombinantly produced AD7C-NTP. The assay is highly sensitive (30-50 pg), linear to 2.0 ng (r2 > 0.99), and reproducible (C.V. < 10%). The utility of the assay has been demonstrated using CSF specimens from early Alzheimer's disease patients and age matched controls (sensitivity of 89% and specificity of 89%). 相似文献
999.
In regenerating periodontal ligament (PDL) around the root of an artificial tooth, an important role is played by some physiologically active substance that promotes adhesion of the cells to the surface of the tooth root and induces cell proliferation and differentiation. In this study, the supernatant of the conditioned medium (CM) of dog periodontal ligament fibroblast (DPLF) was fractionated using an ion exchange chromatography-diethylaminoethyl (IEC-DEAE) column. DPLFs were cultured on hydrophobic dishes coated with each fraction. Cell proliferative activity and alkaline phosphatase (ALPase) activity, including electron microscopic features of the contact surface between the cells and the dish, were investigated. The DPLF-CM was separated by IEC-DEAE column into six fractions. Each fraction promoted an increase in DNA content and ALPase activity of the cultured DPLF, and especially remarkable were fractions 2 and 3. Fraction 2 at a molecular weight (Mw) of 210, 160, 85, 50 and 22 kD, and fraction 3 at Mw = 21 and 23 kD contained the type of proteins not found in other fractions. Electron microscopic analysis revealed that the cells in the coating group were in close contact with the surface of the dishes and that fine fibers protruding from the cell membrane clinged to the dishes. In the control group, a wide gap between the cells and the dishes was observed. These findings suggest that the DPLF-CM fractions contain specific physiological activating factors that induce proliferation and differentiation as well as cell adhesion of the DPLF cells. 相似文献
1000.