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排序方式: 共有153条查询结果,搜索用时 15 毫秒
1.
This paper reports the GC determination of 20 organochlorine pesticides in Chinese drugs Flos Ionicerae and Moluodan etc by the present method of Japan for determinaing pesticide residues. The results suggest that except Folium Isatidis, Radix Codonopsis and Sanqi Pian all accord with the for provisions pesticide residues in Japanese foodstuffs.  相似文献   
2.
The area ratio of analog to digital for mixed-mode chip has been inversely proportional to the process design rule for a given dynamic range objective, in contradiction to the LSI trend. This paper presents a design approach to realize a high degree of size reduction with process design rules for analog circuitry and a signal processing architecture for digital circuitry. A five-level current-mode ΣΔ digital-to-analog converter (DAC) system reveals full scale total harmonic: distortion plus noise (THD+N) of -90 dB and dynamic-range of 100 dB at 3 V (low power of 22 mW). Analog-area down-scaling can be accomplished by this architecture to be 1.09 mm2, using 0.6-μm double-poly double-metal (DPDM) CMOS. For the digital filter, a pipeline instruction sequence with multiplierless architecture also gives small area of 1.98 mm2  相似文献   
3.
To elucidate the role of A1, a new member of the Bcl-2 family of apoptosis regulators active in hematopoietic cell apoptosis, we established mice lacking A1-a, a subtype of the A1 gene in mice (A1-a-/- mice). Spontaneous apoptosis of peripheral blood neutrophils of A1-a-/- mice was enhanced compared with that of either wild-type mice or heterozygous mutants (A1-a+/- mice). Neutrophil apoptosis inhibition induced by lipopolysaccharide treatment in vitro or transendothelial migration in vivo observed in wild-type mice was abolished in both A1-a-/- and A1-a+/- animals. On the other hand, the extent of tumor necrosis factor alpha-induced acceleration of neutrophil apoptosis did not differ among A1-a-/-, A1-a+/-, and wild-type mice. The descending order of A1 mRNA expression was wild-type, A1-a+/-, and A1-a-/-. Taken together, these results suggest that A1 is involved in inhibition of certain types of neutrophil apoptosis.  相似文献   
4.
In order to improve the fracture properties of p, p′-diaminodiphenylmethane-cured epoxy resin, various kinds of aromatic and aliphatic glycidyl compounds were investigated as a modifier at an amount of 30 wt %. Several compounds promoted the fracture toughness. In any glycidyl compounds, however, heat resistance was decreased by the modification. The dynamic mechanical properties of the modified epoxy resins were measured. The crosslinking density ρ was calculated from the theory of rubber elasticity, and the mechanical properties of the resins were discussed in regard to the crosslinking density. Tensile strength was scarcely affected by the crosslinking density. Elongation at break and Izod impact strength increased remarkably with decrease in crosslinking density. The fracture toughness KIc- increased with decrease in crosslinking density except at small ρ.  相似文献   
5.
Band 3 protein is a typical polytropic membrane protein and mediates the exchange of the cellular HCO3- with CI- in plasma, which has been known as the "Chloride Shift". Owing to the "Chloride Shift", red blood cells can discriminate the metabolically active cells from inactive cells and deliver oxygen particularly to metabolically active tissues that produce carbon dioxide. Thus, band 3 protein is a sensor for metabolically active tissues and no excess oxygen is supplied to tissues as far as oxygen is delivered by red blood cells. In this chapter, we review the physiological role of the anion exchange mediated by band 3 protein and our work concerning the structure and function relationship in band 3 protein, that, is, affinity labeling of the active center for the anion exchange with pyridoxal phosphate, conformational change during the anion exchange process, examination of fidelity of hydropathy prediction on band 3 protein, and phosphoenolpyruvate transport mediated by band 3 protein and its clinical application.  相似文献   
6.
Microtubule (MT) protein filaments were used as templates for fabricating Au nanowires as a bottom-up approach for fabricating building blocks for future integrated circuits. Photochemical reduction methods were employed to form Au nanoparticles which bind and uniformly cover the MT filaments. Synthesis of the MT-templated Au nanowires was characterized using UV/vis spectroscopy and transmission electron microscopy (TEM). In addition, binding between the MT filaments and Au nanoparticles was investigated using surface enhanced Raman spectroscopy (SERS) and X-ray photoelectron spectroscopy (XPS) to establish the nature of the binding sites. A variety of functional groups were identified by SERS to interact with the Au including imidazole, sulfur, aromatic rings, amine, and carboxylate. The imidazole ring in the histidine is the most prominent functional group for Au binding. The results from these studies provide better understanding of the binding between Au and the biotemplate and give insight concerning methods to improve Au coverage for MT-templated Au nanowires.  相似文献   
7.
The International Journal of Advanced Manufacturing Technology - This paper presents a novel technology called ‘double-action bending (DAB)’ to eliminate springback in hat-shape forming...  相似文献   
8.
GaFeO3‐type iron oxide is a promising room‐temperature multiferroic material due to its large magnetization. To expand its usability, controlling the ferroelectric and magnetic properties is crucial. In this study, high‐quality GaxFe2–xO3 (x = 0–1) epitaxial films are fabricated and their properties are systematically investigated. All films exhibit room‐temperature out‐of‐plane ferroelectricity, showing that the coercive electric field (Ec) decreases monotonically with x. Additionally, the films show in‐plane ferrimagnetism with a Curie temperature (TC) >350 K at x = 0–0.6. The coercive magnetic field (Hc) decreases with x at x ≤ 0.6, but shows a constant value at x > 0.6, whereas the saturated magnetization (Ms) increases with x at x ≤ 0.6, but decreases with x at x > 0.6. X‐ray magnetic circular dichroism reveals that the large magnetization at x = 0.6 is derived from Fe3+ (3d5) at octahedral sites. The controllable range of the Ec, Hc, and Ms values at room temperature (400–800 kV cm?1, 1–8 kOe, and 0.2–0.6 µB/f.u.) is very wide and differs from those of well‐known multiferroic BiFeO3. Furthermore, the GaxFe2?xO3 films exhibit room‐temperature magnetocapacitance effects, indicating that adjusting TC near room temperature is useful to achieve large room‐temperature magnetocapacitance behavior.  相似文献   
9.
p53 immunohistochemistry is considered an accurate surrogate marker reflecting the underlying TP53 mutation status and has utility in tumor diagnostics. In the present study, 269 primary CRCs were immunohistochemically evaluated for p53 expression to assess its utility in diagnostic pathology and prognostication. p53 expression was wild-type in 59 cases (23%), overexpressed in 143 cases (55%), completely lost in 50 cases (19%), and cytoplasmic in 10 cases (4%). p53 immunoreactivity was associated with tumor size (p = 0.0056), mucus production (p = 0.0015), and mismatch repair (MMR) system status (p < 0.0001). Furthermore, among CRCs with wild-type p53 expression, a significantly higher number of cases had decreased CDX2 than those with p53 overexpression (p = 0.012) or complete p53 loss (p = 0.043). In contrast, among CRCs with p53 overexpression, there were significantly fewer ALCAM-positive cases than p53 wild-type cases (p = 0.0045). However, no significant association was detected between p53 immunoreactivity and the “stem-like” immunophenotype defined by CDX2 downregulation and ALCAM-positivity. Multivariate Cox hazards regression analysis identified tubular-forming histology (hazard ratio [HR] = 0.17, p < 0.0001), younger age (HR = 0.52, p = 0.021), and female sex (HR = 0.55, p = 0.046) as potential favorable factors. The analysis also revealed complete p53 loss (HR = 2.16, p = 0.0087), incomplete resection (HR = 2.65, p = 0.0068), and peritoneal metastasis (HR = 5.32, p < 0.0001) as potential independent risk factors for patients with CRC. The sub-cohort survival analyses classified according to chemotherapy after surgery revealed that CRC patients with wild-type p53 expression tended to have better survival than those with overexpression or complete loss after chemotherapy. Thus, immunohistochemistry for p53 could be used for the prognostication and chemotherapy target selection of patients with CRC.  相似文献   
10.
There are various kinds of analog CMOS circuits in microprocessors. IOs, clock distribution circuits including PLL, memories are the main analog circuits. The circuit techniques to achieve low power dissipation combined with high performance in newest prototype chip in the Super H RISC engines are described. A TLB delay can be decreased by using a CAM with a differential amplifier to generate the match signal. The accelerator circuit also helps to speed up the TLB circuit, enabling single-cycle operation. A fabricated 96-mm2 test chip with the super H architecture using 0.35-m four metal CMOS technology is capable of 167-MHz operation at 300 Dhrystone MIPS with 2.0-W power dissipation.  相似文献   
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