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91.
92.
P Esterre A Raobelison CE Ramarokoto VE Ravaoalimalala P Boisier J Roux 《Canadian Metallurgical Quarterly》1998,20(8):369-376
Increased serum concentrations of soluble intercellular adhesion molecule-1 (sICAM-1, CD54) and of soluble E- (CD62E), but not soluble P- (CD62P) and L- (CD62 L) selectins, were detected in Malagasy patients living in an hyperendemic focus of Schistosoma mansoni. Levels of sICAM-1 remained elevated for several months after treatment with praziquantel. Serum levels of ICAM-1, but not of other markers, were significantly correlated with the disease severity, as indicated by ultrasonographical data, and with some circulating fibrosis markers (at least hyaluronic acid). sICAM-1 level may reflect endothelial inflammatory reactions, probably harmful, in the liver and may be useful for monitoring morbidity evolution in schistosomiasis mansoni. 相似文献
93.
An earlier report indicated that a 26-amino-acid peptide (SA), comprised of the nuclear localization signal (NLS) of fibroblast growth factor-1 (FGF-1) and a membrane-permeable peptide, was able to stimulate DNA synthesis after it was taken up by NIH3T3 fibroblasts. Here, we report that SA, but not a mutant with the NLS motif destroyed, induced DNA synthesis in BALB/c3T3 murine fibroblasts, human vascular endothelial (HUVE) cells, and primary cultured hepatocytes, although the activity was weaker than that of FGF-1. The kinetics of SA-induced DNA synthesis and G1 cyclin expression were similar to those elicited by FGF-1, indicating that SA induces cell cycle progression. Kinetic analysis also suggested that SA stimulates only a fraction of the DNA replication in BALB/c3T3 cells. At high cell densities, SA-induced G1 cyclin expression and DNA synthesis were more strongly inhibited than those induced by FGF-1. SA did not induce cell division in HUVE and BALB/c3T3 cells and did not interfere with FGF-1-stimulated proliferation of HUVE cells. These results indicate that SA is able to partially induce cell cycle progression through a contact-inhibition sensitive signaling pathway, but it is insufficient to support cell mitosis. We also suggest that signaling by SA does not interfere with that of FGF-1. 相似文献
94.
A. D. Kiryukhin V. V. Grigor’ev A. V. Zuev V. V. Zuev N. A. Korolev 《Semiconductors》2007,41(3):259-262
Experimental results of studying the photoconductivity kinetics in silicon doped with either gold or sulfur are reported.
The nonequilibrium charge-carrier concentration was generated by the effect of pulsed laser radiation. The time dependence
of nonequilibrium conductivity was determined by contactless measurements from a variation in the reflected power of the microwave
field. The long-term photoconductivity with the time constant of τ ≈ 1.6 ms at room temperature is observed in the silicon
samples overcompensated with sulfur. Conventional short-term processes (τ ≈ 2–3 μs) characteristic of the centers with deep
levels are observed in the silicon samples doped with gold. These differences are accounted for using the known data on the
energy characteristics of the gold and sulfur levels in the silicon band gap and their charge states.
Original Russian Text ? A.D. Kiryukhin, V.V. Grigor’ev, A.V. Zuev, V.V. Zuev, N.A. Korolev, 2007, published in Fizika i Tekhnika
Poluprovodnikov, 2007, Vol. 41, No. 3, pp. 269–272. 相似文献
95.
96.
LW Wattenberg TS Wiedmann RD Estensen CL Zimmerman VE Steele GJ Kelloff 《Canadian Metallurgical Quarterly》1997,57(24):5489-5492
This investigation is part of a continuing effort to develop effective chemoprevention for carcinogenesis of the lung. The present study explores the use of aerosol administrations for this purpose. The agent selected for initial study was the synthetic glucocorticoid budesonide. This selection was based on previous work in which budesonide added to the diet was found to inhibit pulmonary adenoma formation in female A/J mice. However, high dose levels were required, i.e., of the order of 300 microg/kg, of body weight [L. W. Wattenberg and R. D. Estensen, Carcinogenesis (Lond.), 18: 2015-2017, 1997]. For aerosol administration of budesonide, a nose-only technique has been developed that entails nebulization of the compound dissolved in ethanol and subsequent stripping off of the solvent (less than 3 microl ethanol/liter of air remaining at the site of inhalation). The budesonide particles produced by the apparatus had a mass median aerodynamic diameter of less than 1 microm. An experiment has been carried out in which the inhibitory effects of aerosolized budesonide, given for 1 min six times a week, were studied. Concentrations of budesonide of 26, 81, and 148 microg/liter of air (calculated doses of 23, 72, and 126 microg/kg of body weight) were used. The aerosols were started 1 week after three oral administrations of benzo(a)pyrene (2 mg/20 g of body weight) to female A/J mice. All three doses of budesonide resulted in more than 80% inhibition of pulmonary tumor formation compared to the aerosol control and 90% or greater compared to mice not exposed to aerosol. The difference in inhibition is due to the aerosol procedure itself, which produces a reduction in tumor formation. A decrease in splenic weight (evidence of a systemic effect) occurred at all doses of budesonide. To the best of our knowledge, this is the first published effort at the use of aerosol administration to prevent neoplasia of the respiratory tract. The results of the present study show that administration of a potential chemopreventive agent by aerosol at a low dose can inhibit the occurrence of pulmonary carcinogenesis in female A/J mice. 相似文献
97.
Voice telephony in the internet is of increasing importance since more than one year. The reason is the availability of powerful voice codecs operating on a personal computer and of new application software products. Interworking Units between the public telephone network and the internet are acelerating this trend. This article is giving an overview of history, technology, standards and future prospects of this new type of voice telephony. 相似文献
98.
99.
AA Ferraz VE Cowles RE Condon S Carilli F Ezberci CT Frantzides WJ Schulte 《Canadian Metallurgical Quarterly》1995,61(12):1079-1083
Morphine inhibits propagating and stimulates nonpropagating colon contractions in monkeys and humans. The use of morphine or other opioids that inhibit propulsive contractions prolongs postoperative ileus. In contrast, ketorolac tromethamine, a nonsteroidal analgesic, has no effect on colon contractions in monkeys. In 14 patients having elective abdominal operations, bipolar electrodes were implanted on the right (n = 13) and left (n = 10) colon. Group A (n = 8) received ketorolac, 30 mg IM q6h, for pain relief. Group B (n = 6) needed supplemental morphine, 2-10 mg IV or IM, plus ketorolac to control their pain. Myoelectric activity was recorded from each subject on postop Days 1-5 and analyzed by computer for electrical control activity (ECA), short and long electrical response activity (ERA), and propagation of long ERA. There was a difference between the two groups in return of propagated long ERA bursts that correlated with clinical recovery from postoperative ileus. Postoperative analgesia with ketorolac resulted in faster resolution of ileus compared to morphine plus ketorolac because opioid-induced motor abnormalities in the colon were avoided. 相似文献
100.
N. M. Durakbasa ÖVE P. H. Osanna ÖVE 《e & i Elektrotechnik und Informationstechnik》1998,115(4):207-212
Inspection, measuring and testing instruments are influencing the quality in modern production. Therefore the confirmation of this equipment is an essential quality requirement for the entire production especially at the increasing demands of micro and nanotechnology. Thereby the large expense of the confirmation can be reduced essentially through computer assistance. For this purpose a special method has been developed at the Department for Interchangeable Manufacturing and Industrial Metrology, with which an increase of the flexibility level and efficiency of a system for the management and confirmation of the inspection, measuring and test equipment can be achieved. 相似文献