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991.
JB Vannatta KR Smith S Crandall PC Fischer K Williams 《Canadian Metallurgical Quarterly》1996,71(12):1360-1362
PURPOSE: This randomized controlled study compared the interviewing skills of first-year medical students receiving feedback primarily from standardized patients (SPs) with those of students receiving feedback primarily from faculty. METHOD: All 154 first-year students at the University of Oklahoma College of Medicine in 1993-94 were video-taped to assess baseline and post-instruction interviewing skills. All the students, randomized to one of three study groups, attended two four-hour workshops on interviewing skills. Instruction in the groups was as similar as possible except in the matter of who provided feedback. Two rating systems were used to rate the videotaped interviews for performances of targeted skills. RESULTS: Complete, usable data were available for 120 (78%) of the students. Skill ratings using the Arizona Clinical Interview Rating Scale were significantly higher for the "types of questions used" and "use of empathy" items in the SP-led feedback group. No significant difference in ratings was detected among the groups as measured by the Rotor Interactional Analysis System. CONCLUSION: The SPs were at least as effective as the faculty in effecting behavioral changes in the first-year medical students' interviewing skills. 相似文献
992.
M Sawzdargo T Nguyen DK Lee KR Lynch R Cheng HH Heng SR George BF O''Dowd 《Canadian Metallurgical Quarterly》1999,64(2):193-198
OBJECTIVES: To examine the psychoeducational profile associated with the chromosome 22q11.2 microdeletion (DiGeorge/velocardiofacial syndrome). STUDY DESIGN: Thirty-three patients (aged 6 to 27 years) with a 22q11.2 microdeletion underwent psychoeducational testing as part of a comprehensive evaluation. Nonparametric statistics were used to compare verbal and performance IQ, academic achievement scores, and receptive versus expressive language scores. Post hoc comparisons were made of IQ subtest scores and of language versus verbal IQ. RESULTS: Full-scale IQ ranged from the normal to the moderately retarded range. Mean verbal IQ was significantly higher than mean performance IQ. In a similar manner, mean reading and spelling scores were superior to the mean mathematics score, although achievement scores typically were in the range of verbal IQ. In addition, many children showed clinically significant language impairments, with mean language scores lower than mean verbal IQ. CONCLUSIONS: The IQ and academic profiles are reminiscent of a "nonverbal learning disability," although achievement was not discrepant from IQ. The coincidence of language impairment with a relative strength in reading belies a unique neuropsychologic profile. Educational programming for these children must address both verbal and nonverbal deficits. 相似文献
993.
L.C. Hardie M.J. VandeHaar R.J. Tempelman K.A. Weigel L.E. Armentano G.R. Wiggans R.F. Veerkamp Y. de Haas M.P. Coffey E.E. Connor M.D. Hanigan C. Staples Z. Wang J.C.M. Dekkers D.M. Spurlock 《Journal of dairy science》2017,100(11):9061-9075
The objective of this study was to identify genomic regions and candidate genes associated with feed efficiency in lactating Holstein cows. In total, 4,916 cows with actual or imputed genotypes for 60,671 single nucleotide polymorphisms having individual feed intake, milk yield, milk composition, and body weight records were used in this study. Cows were from research herds located in the United States, Canada, the Netherlands, and the United Kingdom. Feed efficiency, defined as residual feed intake (RFI), was calculated within location as the residual of the regression of dry matter intake (DMI) on milk energy (MilkE), metabolic body weight (MBW), change in body weight, and systematic effects. For RFI, DMI, MilkE, and MBW, bivariate analyses were performed considering each trait as a separate trait within parity group to estimate variance components and genetic correlations between them. Animal relationships were established using a genomic relationship matrix. Genome-wide association studies were performed separately by parity group for RFI, DMI, MilkE, and MBW using the Bayes B method with a prior assumption that 1% of single nucleotide polymorphisms have a nonzero effect. One-megabase windows with greatest percentage of the total genetic variation explained by the markers (TGVM) were identified, and adjacent windows with large proportion of the TGVM were combined and reanalyzed. Heritability estimates for RFI were 0.14 (±0.03; ±SE) in primiparous cows and 0.13 (±0.03) in multiparous cows. Genetic correlations between primiparous and multiparous cows were 0.76 for RFI, 0.78 for DMI, 0.92 for MBW, and 0.61 for MilkE. No single 1-Mb window explained a significant proportion of the TGVM for RFI; however, after combining windows, significance was met on Bos taurus autosome 27 in primiparous cows, and nearly reached on Bos taurus autosome 4 in multiparous cows. Among other genes, these regions contain β-3 adrenergic receptor and the physiological candidate gene, leptin, respectively. Between the 2 parity groups, 3 of the 10 windows with the largest effects on DMI neighbored windows affecting RFI, but were not in the top 10 regions for MilkE or MBW. This result suggests a genetic basis for feed intake that is unrelated to energy consumption required for milk production or expected maintenance as determined by MBW. In conclusion, feed efficiency measured as RFI is a polygenic trait exhibiting a dynamic genetic basis and genetic variation distinct from that underlying expected maintenance requirements and milk energy output. 相似文献
994.
Alphaviruses are mosquito-transmitted RNA viruses that cause important diseases in both humans and livestock. Sindbis virus (SIN), the type species of the alphavirus genus, carries a 11.7-kb positive-sense RNA genome which is capped at its 5' end and polyadenylated at its 3' end. The 3' nontranslated region (3'NTR) of the SIN genome carries many AU-rich motifs, including a 19-nucleotide (nt) conserved element (3'CSE) and a poly(A) tail. This 3'CSE and the adjoining poly(A) tail are believed to regulate the synthesis of negative-sense RNA and genome replication in vivo. We have recently demonstrated that the SIN genome lacking the poly(A) tail was infectious and that de novo polyadenylation could occur in vivo (K. R. Hill, M. Hajjou, J. Hu, and R. Raju, J. Virol. 71:2693-2704, 1997). Here, we demonstrate that the 3'-terminal 29-nt region of the SIN genome carries a signal for possible cytoplasmic polyadenylation. To further investigate the polyadenylation signals within the 3'NTR, we generated a battery of mutant genomes with mutations in the 3'NTR and tested their ability to generate infectious virus and undergo 3' polyadenylation in vivo. Engineered SIN genomes with terminal deletions within the 19-nt 3'CSE were infectious and regained their poly(A) tail. Also, a SIN genome carrying the poly(A) tail but lacking a part or the entire 19-nt 3'CSE was also infectious. Sequence analysis of viruses generated from these engineered SIN genomes demonstrated the addition of a variety of AU-rich sequence motifs just adjacent to the poly(A) tail. The addition of AU-rich motifs to the mutant SIN genomes appears to require the presence of a significant portion of the 3'NTR. These results indicate the ability of alphavirus RNAs to undergo 3' repair and the existence of a pathway for the addition of AU-rich sequences and a poly(A) tail to their 3' end in the infected host cell. Most importantly, these results indicate the ability of alphavirus replication machinery to use a multitude of AU-rich RNA sequences abutted by a poly(A) motif as promoters for negative-sense RNA synthesis and genome replication in vivo. The possible roles of cytoplasmic polyadenylation machinery, terminal transferase-like enzymes, and the viral polymerase in the terminal repair processes are discussed. 相似文献
995.
996.
GN Vespa LA Lewis KR Kozak M Moran JT Nguyen LG Baum MC Miceli 《Canadian Metallurgical Quarterly》1999,162(2):799-806
Galectin-1 is an endogenous lectin expressed by thymic and lymph node stromal cells at sites of Ag presentation and T cell death during normal development. It is known to have immunomodulatory activity in vivo and can induce apoptosis in thymocytes and activated T cells (1-3). Here we demonstrate that galectin-1 stimulation cooperates with TCR engagement to induce apoptosis, but antagonizes TCR-induced IL-2 production and proliferation in a murine T cell hybridoma and freshly isolated mouse thymocytes, respectively. Although CD4+ CD8+ double positive cells are the primary thymic subpopulation susceptible to galectin-1 treatment alone, concomitant CD3 engagement and galectin-1 stimulation broaden susceptible thymocyte subpopulations to include a subset of each CD4- CD8-, CD4+ CD8+, CD4- CD8+, and CD4+ CD8- subpopulations. Furthermore, CD3 engagement cooperates with suboptimal galectin-1 stimulation to enhance cell death in the CD4+ CD8+ subpopulation. Galectin-1 stimulation is shown to synergize with TCR engagement to dramatically and specifically enhance extracellular signal-regulated kinase-2 (ERK-2) activation, though it does not uniformly enhance TCR-induced tyrosine phosphorylation. Unlike TCR-induced IL-2 production, TCR/galectin-1-induced apoptosis is not modulated by the expression of kinase inactive or constitutively activated Lck. These data support a role for galectin-1 as a potent modulator of TCR signals and functions and indicate that individual TCR-induced signals can be independently modulated to specifically affect distinct TCR functions. 相似文献
997.
998.
Plasma levels of tissue plasminogen activator (tPA) increase rapidly in response to specific vasoactive agents, trauma, and neural stimulation. This response has been attributed to acute release of tPA from stored pools within the vascular endothelium and from catecholamine storage vesicles of chromaffin cells. We have tested directly whether tPA can be sorted into the regulated secretory pathway using the murine pituitary-derived neuroendocrine cell line AtT-20 transfected with tPA cDNA. Clones of AtT-20 cells expressing tPA were isolated, and targeting of tPA into the regulated secretory pathway was demonstrated by (1) stimulation of tPA secretion with 8-bromo-cAMP, the secretagogue which promotes the release of dense granule contents; (2) colocalization with ACTH, an endogenous protein that is stored in dense core granules; and (3) retention of newly synthesized tPA in the cell for prolonged periods of time. Laser scanning confocal microscopy analysis of cells immunostained with antibodies to tPA and ACTH showed colocalization at the tips of the neuritic processes under the cytoplasmic membrane, a region where dense granules are known to migrate after maturation. Treatment of the cells with 5 mM 8-bromo-cAMP for 30 min resulted in a 2.41+/-0.36-fold increase in tPA secretion. Both the magnitude of the stimulatory effect and the fraction of the intracellular tPA released were the same regardless of the tPA expression level in the various clones. Pulse-chase experiments showed that a portion of newly synthesized tPA is retained in the cell for at least 4 h and is released into the culture medium in response to 8-bromo-cAMP. These studies indicate that tPA, under the appropriate conditions, can be targeted into the regulated secretory pathway and can be stored for later release by cellular stimuli. 相似文献
999.
Role of microwave heating strategies in enhancing the progress of a first‐order endothermic reaction
Madhuchhanda Bhattacharya Sandeep KR Venkata Tanmay Basak 《American Institute of Chemical Engineers》2013,59(2):656-670
A detailed analysis has been carried out by solving coupled energy and mass balance equations along with Helmholtz equation of microwave propagation to investigate the role of microwave heating strategies in enhancing the progress of a first‐order endothermic reaction in “thin,” “intermediate,” and “thick” regimes of microwave heating. It has been shown that heating strategy plays a critical role in maximizing the efficiency of microwave heated reactors, where progress of reactor can be greatly accelerated at a given input power by either configuring microwave sources at both sides of the reactor or preferentially focusing them on one side. A series of master curves have been provided showing percentage saving of reaction time in various configurations of microwave heated reactors compared to their conventional counterparts, which can be efficiently used to select appropriate heating strategy for different dimension and dielectric properties of the reacting medium. © 2012 American Institute of Chemical Engineers AIChE J, 59: 656–670, 2013 相似文献
1000.
Sarah Y. Dewhirst Michael A. Birkett Jean D. Fitzgerald Alex Stewart-Jones Lester J. Wadhams Christine M. Woodcock Jim Hardie John A. Pickett 《Journal of chemical ecology》2008,34(12):1575-1583
The sex pheromones of many aphid species from the subfamily Aphididae comprise a mixture of the iridoids (cyclopentanoids) (1R,4aS,7S,7aR)-nepetalactol and (4aS,7S,7aR)-nepetalactone. In this paper, we investigate whether other chemicals, in addition to nepetalactol and nepetalactone, are released from Dysaphis plantaginea (rosy apple aphid) oviparae as part of their sex pheromone. Four compounds present in an air entrainment sample collected from D. plantaginea oviparae feeding on apple (Malus silvestris c.v. Braburn) elicited electrophysiological responses from male D. plantaginea. Active peaks were tentatively identified by gas chromatography (GC) coupled with mass spectrometry, with identification confirmed by peak enhancement with authentic compounds on GC columns of different polarities. The electroantennography-active chemicals were (1R,4aS,7S,7aR)-nepetalactol, (4aS,7S,7aR)-nepetalactone, (1S,2R,3S)-dolichodial, and phenylacetonitrile. (1S,2R,3S)-Dolichodial elicited a behavioral response from male D. plantaginea and naïve-mated female parasitoids, Aphidius ervi. This is the first report of electrophysiological and behavioral responses from any aphid morph to (1S,2R,3S)-dolichodial. Whether or not (1S,2R,3S)-dolichodial is a third component of the aphid sex pheromone is discussed. 相似文献