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In search for cancer chemoprevention agents, seven new amide compounds have been synthesized. The structures have been determined based on spectral and chemical data. N-4-(ethoxycarbophenyl)-alpha-naphthamide and N-4-(ethoxycarbophenyl)-beta-naphthamide were shown to be 81% and 79% effective, respectively, for inducing different in HL-60 human promyelocytic leukemia cells at the concentration of 10(-5) mol/L in NBT tests. 相似文献
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Antisera towards neurotensin (NT) and the structurally related peptide, LANT6, were used to characterize immunoreactive peptides and proteins in extracts of chicken tissues. A 17 kDa protein was identified by Western blotting as a potential precursor to NT and LANT6. However, the posttranslational processing of this common precursor appeared to be tissue specific, giving rise to disproportionate amounts of NT and LANT6, along with varying expression of a large molecular LANT6 (M(r), 15 kDa). The intestinal cells containing immunoreactive NT, LANT6, and large molecular LANT6 behaved similarly during fractionation by size and density. These activities also banded together in particles resembling vesicles during centrifugation of isotonic homogenates of tissue. These results suggest that chicken NT and LANT6 are biosynthesized as parts of the same precursor, the processing of which can give rise to a variety of products stored within secretory vesicles. 相似文献
14.
Haemangiopericytoma of nose and paranasal sinuses is relatively uncommon tumour. It occurs in adults in sixth and seventh decades of life. In view of paucity of intranasal haemangiopericytoma old in Indian literature and young age of patient, we are reporting one case in 28-year-old female who presented with recurrent, profuse epistaxis. 相似文献
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SP DiBartola 《Canadian Metallurgical Quarterly》1998,28(3):515-532
The serum sodium concentration reflects the osmolality of the extracellular fluid and provides no direct information about total body sodium content. Patients with hyponatremia may have decreased, normal, or increased total body sodium content. The first step in the approach to the patient with hyponatremia is measurement of plasma osmolality. Hyponatremia with normal plasma osmolality results from hyperlipemia or hyperproteinemia, whereas hyponatremia with increased plasma osmolality results from hyperglycemia or mannitol infusion. Patients with hyponatremia and decreased plasma osmolality may be hypovolemic, hypervolemic, or normovolemic. The volume status of the patient is best determined by history, physical examination, and a few ancillary tests (e.g., total plasma protein concentration, hematocrit, blood pressure, central venous pressure). The clinical signs of hyponatremia are related more to the rapidity of onset than to the severity of the associated plasma hypoosmolality and reflect influx of water into the central nervous system. The main goals of treatment in hyponatremia are to diagnose and manage the underlying disease and, if necessary, to increase serum sodium concentration and plasma osmolality. 相似文献
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1. The presence of dye coupling between striatal neurons was investigated using in vivo intracellular recording and dye injection in adult rats. In 17% of the cases in which a single striatal neuron was injected with Lucifer yellow, more than one labeled neuron was recovered. In control rats, this dye coupling was observed only between single pairs of medium spiny neurons and only when the neuron injected exhibited the Type II response profile as defined by paired-pulse stimulation of corticostriatal afferents. 2. After intravenous administration of the D1/D2 agonist apomorphine at a behaviorally effective dose (i.e., 0.1-0.3 mg/kg), an increase in the incidence (from 17% to 82% of injected cells) and extent (from 2 cells to 3-7 cells labeled per injection) of dye coupling was observed. This effect was mediated by D2 receptor stimulation because administration of the D2 agonist quinpirole caused similar alterations in the incidence and extent of dye coupling (66% coupled). In contrast, administration of the D1 agonist SKF 38393 or the D1 antagonist SCH 23390 did not result in any significant alteration in dye coupling. 3. In control rats, the entire somatodendritic regions of dye-coupled neurons were found to be localized within single matrix compartments of the striatum. However, after intravenous administration of apomorphine or quinpirole, clusters of dye-coupled neurons were found to extend across the patch/matrix boundary. Moreover, dye coupling was observed after injecting cells exhibiting either the Type I or the Type II response profile. 4. In response to D2 receptor stimulation, both the extent and the pattern of coupling between striatal neurons is altered, resulting in direct coupling between neurons that are otherwise functionally and anatomically segregated in the control animal. 相似文献
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Blair J.D. Correale A. Jr. Cranford H.C. Dombrowski D.A. Erdelyi C.K. Hoffman C.R. Lamphere J.L. Lang K.W. Lee J.K. Mullen J.M. Norman V.R. Oakland S.F. 《Solid-State Circuits, IEEE Journal of》1989,24(6):1647-1655
The authors describe a 9.02×9.02-mm chip built in 1-μm CMOS with two levels of metal and an additional mask level for fabricating capacitors. It contains both analog and digital circuits and has provisions for self-test. The function includes the transmitter, receiver, protocol handler, an microprocessor, as well as interfaces for RAM/ROM storage, IBM PC bus, IBM PS/2 bus, IBM 3174 bus, and Motorola 68000 bus. The physical design terrains are formed by 24K circuits of standard cell gates, a 10K-circuit equivalent hand-honed custom microprocessor, and an analog macro. The chip operates from a single 5-V supply, and the power consumption is 0.8 W nominal at 16 Mb/s. The chip can also be operated at 4 Mb/s 相似文献
20.
The digital multistep method generates uniform pseudorandom numbers by transforming sequences of integers obtained by multistep recursions. The statistical independence properties of these pseudorandom numbers depend on the characteristic polynomial of the recursion. We describe a method of calculating characteristic polynomials that are optimal with respect to statistical independence of pairs of successive pseudorandom numbers. Tables of such optimal characteristic polynomials for degrees ≤64 are included. 相似文献