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21.
A 10 bit CMOS A/D converter with 3 V power supply has been developed for being integrated into system VLSI's. In this A/D converter, redundant binary encoders named “twin encoders” enhance tolerance to substrate noise, together with employing differential amplifiers in comparators. The bias circuit using a replica of the amplifier is developed for biasing differential comparators with 3 V power supply. Subranging architecture along with a multilevel tree decoding structure improves dynamic performance of the ADC at 3 V power supply. The A/D converter is fabricated in double-polysilicon, double-metal, 0.8 μm CMOS technology. The experimental results show that the ADC operates at 20 MS/s and the twin encoders suppress the influence of substrate noise effectively. This ADC has a single power supply of 3 V, and dissipates 135 mW at 20 MS/s operation  相似文献   
22.
Complementary medicine (CM) is popular with patients but physicians do not feel at ease with this situation and some fear that the patient might be the loser. Their fear is based on the perception that some CM practitioners have dubious qualifications and competence and that too little is known about the efficacy and safety of many complementary therapies. It follows that, in the interest of the patient and all other parties involved, we urgently need more and better research to fill the void. Integration of complementary medicine into mainstream care requires a minimum of essential evidence. As in all areas of medicine, there can be no short cut to rigorous research.  相似文献   
23.
In this paper we propose a generalized technique to count the required number of registers in a schedule which supports overlapped scheduling and can be applied to the case where a general digit-serial data format is used. This technique is integrated into an integer linear programming (ILP) model for time-constrained scheduling. In the ILP model, appropriate processors of certain data formats are chosen from a library of processors and data format converters are automatically inserted between processors of different data formats if necessary. Then the required number of registers for each data format is evaluated correctly by the proposed technique. Hence an optimal architecture for a given digital signal processing algorithm is synthesized where the cost of registers as well as the cost of processors and data format converters are minimized. It is shown that by including the cost of registers in the synthesis task as proposed in this paper leads to up to 12.8% savings in the total cost of the synthesized architecture when compared with synthesis performed without including the register cost in the total cost.  相似文献   
24.
Facial muscle activity and self-reports were examined for racial bias in 3 studies. In the first 2 experiments, While participants imagined cooperating with a Black or White partner. Experiment 1 manipulated reward structure in the context of cooperating with a deficient partner. Experiment 2 manipulated partner deficiency and willingness to expend compensatory effort. On both facial EMG and self-report measures, joint rewards produced more negative affect than independent rewards. However, all partners were liked more when they were willing to try to compensate for their deficits. In addition, more liking was reported for Black partners, but EMG activity indicated bias against Blacks. Experiment 3 investigated individual differences in prejudice. Again, a greater preference for Blacks than Whites occurred on self-report measures, but in their facial muscle activity, high-prejudiced participants exhibited bias against Blacks.  相似文献   
25.
Neoadjuvant endocrine treatment prior to radical prostatectomy for prostate cancer confined to pelvis has of some value to prevent progression although there are many controversies. In order to improve the prognosis of locally advanced prostate cancer (stage B2 and C), definitive radiotherapy with neoadjuvant endocrine therapy has been investigated. Endocrine therapy reduces the volume of prostate, thus reduces the amount of side effect via reducing the area of irradiated normal tissue. Effect of radiation and that of endocrine therapy to induce apoptosis might be synergistic. The result is favorable although the follow-up period is too short. Further studies are needed to make conclusion.  相似文献   
26.
Two patients with polymyositis (PM) or dermatomyositis (DM) complicated with massive pleural effusion are reported here. Both patients presented a high-grade fever, pleural effusion prominent on the right, and good response to steroid therapy. In a 50-year-old woman with PM, combined process of pleural inflammation, cardiomyopathy and coexisting hypothyroidism were considered to be responsible for the accumulation of the massive pleural effusion. However, in a 34-year-old man with DM, pleural inflammation associated with interstitial pneumonia or pleural microvasculopathy in DM was considered to be responsible for the accumulation of the massive pleural effusion.  相似文献   
27.
28.
We report here a novel type of ceramidase of Pseudomonas aeruginosa AN17 isolated from the skin of a patient with atopic dermatitis. The enzyme was purified 83,400-fold with an overall yield of 21.1% from a culture supernatant of strain AN17. After being stained with a silver staining solution, the purified enzyme showed a single protein band, and its molecular mass was estimated to be 70 kDa on SDS-polyacrylamide gel electrophoresis. The enzyme showed quite wide specificity for various ceramides, i.e. it hydrolyzed ceramides containing C12:0-C18:0 fatty acids and 7-nitrobenz-2-oxa-1, 3-diazole-labeled dodecanoic acid, and not only ceramide containing sphingosine (d18:1) or sphinganine (d18:0) but also phytosphingosine (t18:0) as the long-chain base. However, the enzyme did not hydrolyze galactosylceramide, sulfatide, GM1, or sphingomyelin, and thus was clearly distinguished from a Pseudomonas sphingolipid ceramide N-deacylase (Ito, M., Kurita, T., and Kita, K. (1995) J. Biol. Chem. 270, 24370-24374). This bacterial ceramidase had a pH optimum of 8.0-9.0, an apparent Km of 139 microM, and a Vmax of 5.3 micromol/min/mg using N-palmitoylsphingosine as the substrate. The enzyme appears to require Ca2+ for expression of the activity. Interestingly, the 70-kDa protein catalyzed a reversible reaction in which the N-acyl linkage of ceramide was either cleaved or synthesized. Our study demonstrated that ceramidase is widely distributed from bacteria to mammals.  相似文献   
29.
We report a nephrotic syndrome patient with eosinophilia who developed ileus, epigastralgia and malabsorption due to strongyloidiasis which became symptomatic by steroid therapy. The patient was then treated with thiabendazole and recovered. A percutaneous renal biopsy revealed minimal change nephrotic syndrome. This renal injury may be brought on by severe infection of Strongyloides stercoralis. It is important to rule out strongyloidiasis prior to corticosteroid therapy to patients from eosinophilia endemic areas.  相似文献   
30.
Circularly polarised printed antenna fed by coplanar waveguide   总被引:1,自引:0,他引:1  
Matsuzawa  S. Ito  K. 《Electronics letters》1996,32(22):2035-2036
A new structure of the circularly polarised printed antenna fed by coplanar waveguide (CPW) is proposed. FDTD analysis predicts the radiation of the circularly polarised wave from the antenna. The validity of this analysis is established by comparing with experimental results  相似文献   
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