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A 41-GHz 4-b adder-accumulator test circuit implemented in InP double heterojunction bipolar transistor (DHBT) technology using 624 transistors is reported. High clock rates are obtained by combining the logic functions into pipelined latches. The adder-accumulator contains a single-level parallel-gated carry circuit that is used as a step toward reduced power consumption. The carry circuit has a maximum clock frequency of 55 GHz. The accumulator architecture employs modular, pipelined 2-b adders and is cascadable to 2 N-bits. The test circuit includes a 4-b digital to analog converter (DAC) that facilitates demonstration of high-speed operation.  相似文献   
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A Discfilter with 10 and 18 microm filter openings, respectively, was placed in parallel to a flotation plant for separation of biological flocs from a post-denitrifying Kaldnes Moving Bed Process, the last treatment step at the municipal wastewater treatment plant at Sj?unda, Malm?, Sweden. The effluent concentrations from the 10 and 18 microm filter were 2-5 and 2-8 mg SS L(-1), respectively, which is comparable to, or better than, the flotation plant. Comparison with experiences from activated sludge plants shows that the Discfilter works especially well after the Kaldnes process. Particle size distribution (PSD) studies show that particles larger than the filter openings of 10 and 18 microm are separated with approximately 90% efficiency, whereas most of the smaller particles pass the filter. This fact indicates that the major particle separation mechanism is physical blocking. These findings point to the possibility of improving the prediction of the separation efficiency by combining measurements of turbidity and suspended solids with particle size analysis.  相似文献   
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OBJECTIVE: The purpose of this study was to evaluate ERCP and CT findings of ectopic drainage of the common bile duct into the duodenal bulb. CONCLUSION: Although rare, the diagnosis of ectopic drainage of the common bile duct into the duodenal bulb is important to prevent inadvertent damage during biliary tract or gastric surgery and to clarify the cause of chronic peptic ulcers.  相似文献   
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Loss of heterozygosity at chromosome 8p21-22 is common in human prostate cancer, suggesting the presence of one or more tumor suppressor genes at this locus. A homeobox gene that is expressed specifically in adult human prostate, NKX3.1, the expression of which is regulated by androgen, maps to chromosome 8p21. Fine structure in situ mapping showed that NKX3.1 is proximal to MSR32 (macrophage scavenger receptor type II) and LPL (human lipoprotein lipase) and very close to NEFL (human neurofilament light chain) on 8p21. Single-strand conformational polymorphism analysis of 48 radical prostatectomy cancer specimens and 3 metastases for the entire coding region of NKX3.1 showed no tumor-specific sequence alterations in 50 specimens and total absence of the gene in 1 specimen known to have a biallelic deletion of 8p21. NKX3.1 was found to have a polymorphism at nucleotide 154 in codon 52 that resulted in a CGC-->TGC sequence change and an Arg-->Cys amino acid alteration (R52C). This polymorphism was present in 20% of DNA samples. If NKX3.1 is a target of the 8p21 LOH, it is not via disruption of the coding region of the gene.  相似文献   
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Cultured hepatocytes of silver eel actively secreted only chylomicron-like lipoprotein. The rate of secretion per mg cellular protein per 24 hr was 2.2 times higher compared with that by yellow eel hepatocytes. Silver eel hepatocytes secreted lipids 2.5 times higher through the lipoprotein than yellow eel hepatocytes. Main lipid was triacylglycerol in either secreted lipoprotein and composition of apolipoproteins of both secreted lipoproteins was the same. The incorporation of 3H-leucine into the lipoprotein secreted by silver eel hepatocytes was 2.4 times higher, but that of 14C-acetate was not significantly different. Protein and lipids composition of plasma lipoproteins of silver eel was significantly higher and lower compared with those of yellow eel, respectively. We suggest that the secreted lipoprotein of silver eel hepatocytes transport much more lipids to other tissues than that of yellow eel hepatocytes.  相似文献   
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The mode of interaction between muramyl dipeptide (MDP), a compound with immunopharmacological activities, and 5-hydroxtryptamine (5-HT, serotonin) was studied in isolated nerve-smooth muscle preparations of the carp stomach. Application of exogenous 5-HT evoked direct smooth muscle contractions; electric neurogenic stimulation evoked twitches due to release of 5-HT from nerve endings. Contractions evoked by a high concentration of 5-HT (3-30 microM) were resistant to atropine and potentiated in the presence of MDP. Isamoltan (5-HTID antagonist) decreased the amplitude of contractions, whereas ketanserin (5-HT2 antagonist) and MDL 72,222 (5-HT3 antagonist) had no effect. The addition of low concentrations (0.1-1.5 microM) of 5-HT did not contract the preparation but caused a decrease in the amplitude of neurogenic twitches, which might be due to the presynaptic inhibition of serotonin release. This effect of 5-HT was not changed by isamoltan or ketanserin, but it was largely reduced in the presence of 5-HT3 antagonists tropisetron and MDL 72,222. This inhibitory effect of 5-HT on twitch amplitude was potentiated by MDP. The interaction of MDP with the serotonergic system thus involved not only potentiation of the postsynaptic effect of higher 5-HT concentrations, which might have been mediated via the 5-HT1 subsystem, but also presynaptic inhibition. MDP enhancement of 5-HT's inhibitory effect, mediated via 5-HT3 receptors, might represent a new feature in mutual 5-HT-MDP interactions.  相似文献   
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