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61.
62.
Leyton Marco; Casey Kevin F.; Delaney J. Scott; Kolivakis Theodore; Benkelfat Chawki 《Canadian Metallurgical Quarterly》2005,119(6):1619
The authors used the acute phenylalanine-tyrosine depletion (APTD) method to test the effect of transient catecholamine precursor depletion on cocaine craving, euphoria, and self-administration. Eight nondependent, nontreatment-seeking cocaine users self-administered 3 doses of cocaine (0.6, 1.5, 3.0 mg/kg, taken intranasally) following ingestion of (a) a nutritionally balanced amino acid mixture, (b) APTD, and (c) APTD followed by L-dopa/carbidopa (2 × 100 mg/25 mg). APTD decreased both cue and cocaine-induced drug craving but not euphoria or self-administration. APTD + L-dopa also decreased drug craving, possibly reflecting the ability of L-dopa to transiently decrease dopamine cell firing. Together, these preliminary results suggest that the craving elicited by cocaine and cocaine cues is related to changes in catecholamine neurotransmission. Euphoria and the self-administration of freely available drugs by regular users, in comparison, might be better accounted for by other mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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SJ Plummer MJ Paris J Myles R Tubbs J Crowe G Casey 《Canadian Metallurgical Quarterly》1997,20(4):354-362
Rearrangements or loss of chromosome 17 are frequent events in breast tumors. Chromosome 17 contains at least four genes implicated in breast cancer (TP53, ERBB2 (Her2/neu), BRCA1, and NM23), as well as other putative tumor suppressor genes and oncogenes implicated in loss of heterozygosity or allelic imbalance studies. Allelic imbalance represents the addition or loss of genetic material in tumor samples, providing circumstantial evidence for the location of cancer related genes. We have analyzed a panel of 85 breast tumor/normal tissue pairs with 21 PCR-based short tandem repeat (STR) markers located at 17q12-qter to more precisely define regions of allelic imbalance and to determine their relation to clinical parameters. Our analysis revealed at least four common regions of allelic imbalance: proximal to BRCA1, including D17S800 (17q12); distal to NM23 around D17S787 (17q22); near the growth hormone (GH) locus, at D17S948 (17q23-24); and between markers D17S937 and D17S802 (17q25). These data also reveal that loss (or gain) of 17q genetic material correlates with poorly differentiated (grade III) tumors (P = < 0.001), high S phase fraction (P = 0.034), and positive TP53 immunohistochemical staining (P = 0.011). However steroid receptor status, ERBB2 (Her2/neu) staining, and aneuploidy do not correlate with allelic imbalance at 17q. 相似文献
65.
Weinstein Cheryl S.; Kaplan Edith; Casey M. B.; Hurwitz Irving 《Canadian Metallurgical Quarterly》1990,4(2):117
103 female college students (aged 18–24 yrs) were administered the Rey-Osterrieth Complex Figure on Copy, Immediate Recall, and 20-min Delayed Recall. Ss were grouped based on handedness, familial handedness, and academic major (mathematics/science and nonmath/science). Based on the scoring system of D. Waber and J. Holmes (see PA, Vols 72:24305 and 74:9917) the mathematics/science anomalous dominance groups obtained higher mean scores than all other subgroups, and the non-math/science familial right-handers were the low performers. The high-performing groups may have an increased ability to coordinate the use of left- and right-hemisphere processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
The capabilities of a multi-tethered aerostat positioning system are investigated using experimental and simulation results. The system consists of a platform supported by a helium-filled aerostat and attached to three anchored ground tethers actuated using computer-controlled winches. The experimental system was designed to perform a proof-of-concept study of a novel large-scale radio telescope requiring a receiver to be positioned accurately at an altitude of up to 500 m. Results from a series of flight tests are presented with a comparison between the passive response of the system and the response using proportional, integral, and derivative (PID) controllers with a position feedback. The motion of the platform is smaller for all cases using the feedback control. To improve on the PID results, a dynamics model of the system is used to develop and simulate optimal and feedforward (FF) control strategies. The optimal linear quadratic Gaussian (LQG) controller offers a 50% improvement over the PID controller, and both the LQG and the PID feedback controllers were shown to benefit considerably from the addition of a FF control term that exploits the measurements of the system's main disturbance force 相似文献
67.
This paper describes the step-by-step process of repair and upgrade which restored a damaged 40-year-old 3.5 MW hydroelectric power plant to service after nearly six years of downtime. Detailed information is provided on the approach to the restoration work taken by the Massachusetts Water Resources Authority (USA). Hidden damage, outdated turbogenerator protective relaying, and inadequate surge protection are discussed 相似文献
68.
Moser Casey J.; Jones Rebecca A.; Zaorski Donna M.; Mirsalimi Hamid; Luchner Andrew F. 《Canadian Metallurgical Quarterly》2005,42(3):267
For many years, the impact of sibling relationships on psychological development has been neglected in the literature, overshadowed by the role of the parent-child relationship. As a result, attention to sibling dynamics and sibling transference as valuable information for case formulation and treatment interventions has not been used to its maximum potential. The authors demonstrate how deliberate consideration of sibling dynamics as well as the transferences and countertransferences associated with those dynamics can facilitate treatment. Several important sibling dynamics are discussed, including siblings' influences on identity development; sibling rivalry, jealousy, envy, guilt, and resentment; and sibling attachment. The impact of sibling dynamics on adult love relationships is discussed, as are potential effects of sibling abuse and sibling bereavement. Examples of how these dynamics can manifest themselves in transference and countertransference reactions and suggestions for working with those dynamics are illustrated with clinical examples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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E. coli strain HB101 was genetically engineered to a fluorescent phenotype by transformation with a plasmid containing complementary DNA for a green fluorescent protein. The level of fluorescence in the transformed strain was directly proportional to the number of viable cells. There was a rapid decrease in fluorescence when transformed cells were inoculated into lamivudine solutions containing ten different preservative formulations. The decrease in fluorescence correlated to a decrease in the number of viable cells, allowing the relative antimicrobial properties of each solution to be compared. This methods provides a simple, rapid (< 2 min/assay), and accurate means of determining the effects of antimicrobial solutions on the viability of E. coli. 相似文献