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1.
Narrative transportation is described as a state of detachment that arises when one becomes immersed in the narrative of a story. Participants viewed either an intact version of an engaging 20 min film, “Bang You’re Dead!,” (1961) by Alfred Hitchcock (contiguous condition), or a version of the same film with scenes presented out of order (noncontiguous condition). In this latter condition, the individual scenes were intact but were presented out of chronological order. Participants were told a cover story that we were interested in the amount of gun violence depicted in films. Both groups were given the goal to remember to lift their hand every time they heard the word “gun” spoken during the film. Results revealed that participants were significantly less likely to remember to execute their goal in the contiguous condition, presumably because this narrative transported viewers’ attention and thereby “hijacked” processing resources away from internal goals.  相似文献   
2.
Autocrine activation of the epidermal growth factor (EGF) receptor on keratinocytes has been recognized as an important growth regulatory mechanism involved in epithelial homeostasis, and, possibly, hyperproliferative diseases. Insulin-like growth factor (IGF)-1 and insulin have been shown to be paracrine keratinocyte mitogens that bind to the type I IGF receptor which is expressed on actively proliferating keratinocytes in situ. In this report, we demonstrate that IGF-1/insulin induced production of keratinocyte-derived autocrine growth factors that bind to the EGF receptor. Increased steady-state mRNA levels for transforming growth factor alpha (TGF-α) and for amphiregulin (AR) were observed upon incubation of keratinocytes with mitogenic concentrations of IGF-1. IGF-1 also induced production and secretion of TGF-α and AR proteins as detected by immunoassays. An EGF receptor antagonistic monoclonal antibody abolished the mitogenic effect of IGF-1 on cultured keratinocytes. These results suggest that stimulation of keratinocyte growth by IGF-1 requires activation of an EGF receptor-mediated autocrine loop. © 1995 Wiley-Liss, Inc.  相似文献   
3.
Mass spectrometry is the predominant analytical tool used in the field of plant lipidomics. However, there are many challenges associated with the mass spectrometric detection and identification of lipids because of the highly complex nature of plant lipids. Studies into lipid biosynthetic pathways, gene functions in lipid metabolism, lipid changes during plant growth and development, and the holistic examination of the role of plant lipids in environmental stress responses are often hindered. Here, we leveraged a robust pipeline that we previously established to extract and analyze lipid profiles of different tissues and developmental stages from the model plant Arabidopsis thaliana. We analyzed seven tissues at several different developmental stages and identified more than 200 lipids from each tissue analyzed. The data were used to create a web-accessible in silico lipid map that has been integrated into an electronic Fluorescent Pictograph (eFP) browser. This in silico library of Arabidopsis lipids allows the visualization and exploration of the distribution and changes of lipid levels across selected developmental stages. Furthermore, it provides information on the characteristic fragments of lipids and adducts observed in the mass spectrometer and their retention times, which can be used for lipid identification. The Arabidopsis tissue lipid map can be accessed at http://bar.utoronto.ca/efp_arabidopsis_lipid/cgi-bin/efpWeb.cgi .  相似文献   
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Two crosses between Triticum turgidum wheat lines differing in their response to chlormequat (CCC) were tested. In the F2 population of one cross, which was segregating for the Rht1 dwarfing allele, each plant was cloned by separation of two tillers, one of which was treated with CCC. The tall (rht1/rht1) and the intermediate (Rht1/rht1) genotypes showed a greater response to CCC than the semi-dwarf (Rht1/Rht1) genotype, as expressed by culm length and date of ear emergence. The F3 families of another cross and their two semi-dwarf parents were grown in a three-replicated field test in paris of rows, one of which was treated with CCC. In one of the parents and in 1/4 of the F3 families CCC induced a wide-angled tiller growth, suggesting a monogenic control of this growth habit in response to CCC.Based on an M.Sc. thesis presented by the senior author to the Faculty of Agriculture of The Hebrew University of Jerusalem.  相似文献   
6.
Entire bucks (N = 7) exhibited pronounced liveweight gains over spring and summer months (October-February), to reach a peak mean weight of 59.8 kg, and rapid liveweight losses over the rutting period (April-May) with a minimum mean liveweight of 54.2 kg. Mean neck girth and serum testosterone levels increased during late summer (January-March) and peaked at 387 mm and 12 ng/ml respectively immediately before the onset of the rut (April). Thereafter both measures declined during winter and spring months (June-December). Bucks castrated prepubertally (N = 11) exhibited similar but less pronounced changes in mean liveweight and neck girth, in the absence of any change in testosterone secretion. Peak mean testicular diameter of entire bucks (39 mm) occurred immediately before the rut and was followed by testicular regression over winter and spring months (June-November), such that the testes attained their minimum mean size of 18 mm diameter in early summer (November). Motile spermatozoa were absent from ejaculates collected in summer (November 1983, 1984; January 1984). However, ejaculates collected pre-rut (late March), immediately post-rut (June) and in early spring (September) contained successively increasing numbers of motile spermatozoa. A further 14 polled, entire bucks were given orally 5 mg (N = 7; Group A) or 20 mg (N = 7; Group B) melatonin at 15:30 h daily from 1 December 1983 to 14 January 1984 (45 days). Seven control bucks (Group C) received vehicle ration only. The measurements taken for bucks in Groups A and B were not significantly different (P greater than 0.1) on any sampling date and the data for these 2 groups were pooled. Mean serum testosterone concentrations and mean ejaculate volume were not significantly different between melatonin-treated and control bucks on any sampling date, although other measures exhibited significant differences (P less than 0.05) at various treatment or post-treatment dates: melatonin-treated bucks showed a transiently greater increase in neck muscle development during and immediately after treatment, a slight retardation of liveweight gain between 45 and 75 days after treatment, an earlier peak in maximum mean testicular diameter and an earlier onset of sperm presence in ejaculates.  相似文献   
7.
The direct inhibition of secretion by pancreastatin was investigated in rabbit isolated parietal cells. Pancreastatin exerted no influence on basal aminopyrine uptake. Pancreastatin inhibited histamine stimulated aminopyrine uptake through a decrease in intracellular cAMP. Pancreastatin inhibition of histamine stimulated uptake was blocked in the presence of pertussis toxin. Pancreastatin also inhibited the carbachol stimulated increase in aminopyrine accumulation. However, the effects of pancreastatin on carbachol stimulation were not reversed by pertussis toxin. Pancreastatin did not alter the carbachol induced increase in cytosolic free calcium. Thus, pancreastatin appears to inhibit parietal cell signal transduction at multiple points along the second messenger pathways.  相似文献   
8.
Summary Recently, the Wilson's disease locus (WND) has been mapped to the long arm of chromosome 13. We have analyzed segregation of serveral chromosome 13 markers flanking the WND locus and used multipoint linkage analysis to determine the most likely WND genotype of each of 57 unaffected individuals in 5 Wilson's disease families. Approximately 46% of these could be classified as carrier (heterozygote), homozygous normal, or homozygous affected (not yet symptomatic) with a probability of at least 90%, while 77% could be classified with a probability of at least 80%. Our results demonstrate that even though there is a significant decrease on average in serum copper concentration in Wilson's disease heterozygotes compared to normal homozygotes, other sources of variation in serum copper concentration are much greater and preclude use of serum copper to detect heterozygotes for Wilson's disease. Subsequent analyses showed that a familial component, independent of WND genotype, is the major factor accounting for variation in ceruloplasmin levels among unaffected individuals; age is another factor accounting for more variation in copper levels among unaffected individuals than WND genotype.  相似文献   
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10.
Antinociception of imipramine (I) and its effect in combination with fentanyl (F) was evaluated in rabbits using electrically-induced lick chew responses via tooth pulp stimulation as the model of nociception. Acute i.v. injections of I elicited a graded dose response comparable to i.v. morphine (M) with I ED 50 = 4.35 mg/kg (2.31-8.14, 95% CL) and M ED 50 = 1.81 mg/kg (1.11-3.90), with no differences in the slopes between the two curves. The lethal dose of I was 10 mg/kg. An i.v. dose of I twice the ED 50 elicited an antinociceptive effect of more than 50% maximum possible effect (MPE) for 90 minutes with peak effect of 82% MPE occurring at 15 minutes. These effects of I were not reversed by a morphine-reversal dose of naloxone (0.1 mg/kg i.v.) but were reversed with a ten fold dose of naloxone. F ED 50 values (mcg/kg) were lowered from 11.35 to 2.70, 0.74 and 0.33 with increasing pretreatment doses of I (1.0, 2.1 and 3.2 mg/kg). These magnitudes of potency increases of F were 4.2, 15.3 and 34.4 fold respectively. A single i.v. ED 50 dose of I extended the time to 50% MPE of an ED 90 dose of F from 26 minutes to 77 minutes; of a 2 X ED 50 dose of F from 17 minutes to 28 minutes. Data points for three different combinations of I and F fell significantly within the synergistic field of an ED 50 isobologram and a polynomial equation described the curve best fitting the data points. F alone (i.v. ED 50 dose) increased the PaCO2 values to 74% above controls and three different combinations with I showed no increases in PaCO2 values above controls. I alone did not significantly cause any change in PaCO2 values from controls.  相似文献   
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