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101.
RM Summers J Andrasko-Bourgeois IM Feuerstein SC Hill EC Jones MK Busse B Wise KE Bove BA Rishforth E Tucker TL Spray JM Hoeg 《Canadian Metallurgical Quarterly》1998,98(6):509-518
Hepatitis C chronically infects approximately 1.5% of Americans and is the most common clinical problem facing hepatologists. Since the virus was initially described in 1989, development of an effective therapy has been challenging. Although several different therapeutic agents have been used, no therapy has been shown to reliably eradicate the virus. Interferon-alpha, a cytokine with immunostimulatory and anti-viral properties, has become the therapy of choice for patients with chronic hepatitis C infection. Trials assessing the efficacy of interferon-alpha have characterized host and viral factors predictive of responses to treatment. A thorough understanding of these predictive factors is requisite to providing cost-effective therapeutic decisions for the patient with chronic hepatitis C infection. 相似文献
102.
103.
In this work, we designed, fabricated and tested a disposable, flow-through amperometric sensor for free chlorine determination in water. The sensor is based on the principle of an electrochemical cell. The substrate, as well as the top microfluidic layer, is made up of a polymer material. The advantages include; (a) disposability from low cost; (b) stable operation range from three-electrode design; (c) fluidic interconnections that provide on line testing capabilities; and (d) transparent substrate which provides for future integration of on-chip optics. The sensor showed a good response and linearity in the chlorine concentration ranging from 0.3 to 1.6 ppm, which applies to common chlorination process for drinking water purification. 相似文献
104.
D.L. Butler P.S. Cho M.W. Chbat J. Goldhar F.-S. Choa G.L. Burdge 《Photonics Technology Letters, IEEE》1996,8(6):779-781
We demonstrate stable operation of a NOLM using orthogonally polarized control and signal beams in nonpolarization-preserving, single-mode fiber. The NOLM can transcribe data from an optically incoherent input at one wavelength to a coherent output over a range of wavelengths. Operation of the NOLM without tuning for the input bit rate is possible over a range of bit rates from less than 1 Gb/s to more than 50 Gb/s. 相似文献
105.
We used the fluorescent labelled dopamine D1-receptor antagonist Bodipy-SCH 23390 for the cellular localization of D1-ligand binding sites in the retinae of different vertebrates (teleosts, Xenopus, turtle, rat and rabbit). Competition experiments with unfixed cryosections of fish retina were performed to characterize the binding conditions of Bodipy-labelled SCH 23390. Tissue bound [3H]SCH 23390 was displaceable with increased amounts of bodipy-SCH 23390. The pharmacological specificity of the D1 fluorescent antagonist was determined by competition experiments with an excess of unlabelled SCH 23390. This treatment significantly reduced the level of fluorescence of the retina confirming the specificity of the binding. We observed a homogeneously distributed fluorescence signal in both plexiform layers in unfixed cryosections of fish, frog, turtle, rat and rabbit. Similar staining intensities of both plexiform layers were found in frog, turtle, rat and rabbit retina. In teleosts, the label of the outer plexiform layer was markedly more intense. Non-specific label was associated with photoreceptor outer and inner segments. The specific labelling of both plexiform layers indicates a mismatch of dopamine releasing and D1-binding sites, and suggests a possible extrasynaptic localization of the D1-receptor. The physiological significance of the observed distribution of D1-ligand binding sites is discussed with respect to the role of dopamine in controlling adaptational processes in the retina. 相似文献
106.
Jung‐Hyun Cho Michael Bass Hans P. Jenssen 《Journal of the Society for Information Display》2007,15(12):1029-1036
Abstract— Several rare‐earth‐doped fluoride crystals that are excited to emit visible light by sequential two‐photon absorption have been investigated as display‐medium candidates for static volumetric three‐dimensional displays. Dispersion of powders of these materials in a refractive‐index‐matched polymer is reported because such a medium may result in a scalable display. The scattering problem in such a medium is greatly reduced by index‐matching the polymer to the crystalline particles. An index‐matching condition that optimizes the performance is identified. 相似文献
107.
Structural Antecedents to Knowledge and Participation: Extending the Knowledge Gap Concept to Participation 总被引:1,自引:0,他引:1
This paper investigates relationships between community characteristics and levels of knowledge and participation examined at both the individual and the community levels. This research extends the knowledge gap concept to a parallel phenomenon, the participation gap. Results from the Social Capital Benchmark Survey 2000 showed that community density, education, and cohesion were significant positive predictors of knowledge but less consistent predictors of participation at the individual level. At the community level, relationships were even stronger, though cohesion was associated with higher mean levels of participation and reduced participation gaps, whereas population density was associated with lower levels of participation and increased gaps. 相似文献
108.
Tae-Sung Jung Do-Chan Choi Sung-Hee Cho Myong-Jae Kim Seung-Keun Lee Byung-Soon Choi Jin-Sun Yum San-Hong Kim Dong-Gi Lee Jong-Chang Son Myung-Sik Yong Heung-Kwun Oh Sung-Bu Jun Woung-Moo Lee Haq E. Kang-Deog Suh Ali S.B. Hyung-Kyu Lim 《Solid-State Circuits, IEEE Journal of》1997,32(11):1748-1757
A 3.3-V 16-Mb nonvolatile memory having operation virtually identical to DRAM with package pin compatibility has been developed. Read and write operations are fully DRAM compatible except for a longer RAS precharge time after write. Fast random access time of 63 ns with the NAND flash memory cell is achieved by using a hierarchical row decoder scheme and a unique folded bit-line architecture which also allows bit-by-bit program verify and inhibit operation. Fast page mode with a column address access time of 21 ns is achieved by sensing and latching 4 k cells simultaneously. To allow byte alterability, nonvolatile restore operation with self-contained erase is developed. Self-contained erase is word-line based, and increased cell disturb due to the word-line based erase is relaxed by adding a boosted bit-line scheme to a conventional self-boosting technique. The device is fabricated in a 0.5-μm triple-well, p-substrate CMOS process using two-metal and three-poly interconnect layers. A resulting die size is 86.6 mm2, and the effective cell size including the overhead of string select transistors is 2.0 μm2 相似文献
109.
N Cho Y Nara M Harada T Sugo Y Masuda A Abe K Kusumoto Y Itoh T Ohtaki T Watanabe S Furuya 《Canadian Metallurgical Quarterly》1998,46(11):1724-1737
On the basis of structural information for the cyclic hexapeptide endothelin (ET) receptor antagonist, TAK-044, a series of thieno[2,3-d]pyrimidine-2,4-dione derivatives bearing a carboxyl group and aromatic rings that were important for receptor binding were designed, synthesized, and evaluated for ET receptor binding affinities and inhibitory activities against ET-induced vasoconstriction. Optimization of each substituent in the thieno[2,3-d]pyrimidine ring led to the discovery of a novel and potent nonpeptide ET receptor antagonist, 6-(4-methoxymethoxyphenyl)-5-methylsulfonylaminomethyl-1-(2- methylthiobenzyl)-2,4-dioxo-1,2,3,4-tetrahydrothieno[2,3-d]p yrimidine-3- acetic acid (32 g), which binded to human ETA and ETB receptor subtypes with affinities (IC50) of 7.6 and 100 nM, respectively. Compound 32 g effectively antagonized ET-induced vasoconstriction and the inhibitory effect mediated by the ETB receptor was more potent than that of bosentan, while the inhibitory effect mediated by the ETA receptor was slightly less potent than that of bosentan. 相似文献
110.
OBJECTIVE: To examine the changes in neutrophil deformability, aggregation, and adherence in response to stimulation with proinflammatory cytokines and bacterial toxins. DESIGN: Prospective, randomized trial. SETTING: Research laboratory. SUBJECTS: Neutrophils isolated from healthy volunteers. INTERVENTIONS: Neutrophils were exposed to tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-8, their combination, endotoxin (LPS), lipoteichoic acid (LTA), and staphyloccocal enterotoxin B (SEB). Neutrophil deformability was measured as percent neutrophils filtered through 5-microm diameter filters. Aggregation was measured using a platelet aggregometer. Adherence was determined by examining the binding of neutrophils to albumin-coated latex beads. MEASUREMENTS AND MAIN RESULTS: Exposure to TNF-alpha and IL-1beta led to significant decreases in neutrophil filterability, which was attenuated by cytochalasin D pretreatment. LPS and LTA also decreased deformability, suggesting that these toxins directly stimulated neutrophils independent of cytokines. IL-8 and SEB did not significantly affect neutrophil deformability. TNF-alpha and LPS were associated with significant neutrophil aggregation, which was inhibited by pretreatment with anti-CD18 antibodies. Neutrophil aggregation was not affected by IL-1beta, LTA, or SEB. TNF-alpha, IL-8, and LPS increased neutrophil adherence, which also was attenuated by pretreatment with anti-CD18 antibodies. IL-1beta, LTA, and SEB did not significantly affect neutrophil adherence. CONCLUSIONS: Cytokines and bacterial toxins differ in their effects on neutrophil deformability, aggregation, and adherence. Of the cytokines examined, TNF-alpha appears to have the greatest direct effects on neutrophil rheology. Similarly, endotoxin appears to have greater direct effects on neutrophil rheology than the Gram-positive bacterial toxins, LTA, and staphylococcal enterotoxins. 相似文献