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排序方式: 共有576条查询结果,搜索用时 15 毫秒
1.
Margaret M Plack Maryanne Driscoll Maria Marquez Lynn Cuppernull Joyce Maring Larrie Greenberg 《Ambulatory Pediatrics》2007,7(4):285-291
OBJECTIVE: Reflection enables learners to analyze their experiences and capture the wisdom that lies within. Effective teaching requires reliable methods of assessment. Several methods of assessing reflective writing have been described; however, they often require significant training, and reliability has seldom been assessed. This study was designed to determine the interrater reliability of a method of assessing reflective writing by using a modified Bloom's Taxonomy. METHODS: Twenty-one third-year medical students maintained reflective journals throughout their pediatric clerkship. A coding schema based on Bloom's Taxonomy was developed to assess the level of cognitive processing evident in the journals. Journals were independently assessed by 3 raters. Percent agreement, kappa statistics, and intraclass correlation coefficients (ICC [2,1]) were used to assess interrater reliability. RESULTS: Three hundred eight entries from 21 journals were assessed. Percent agreement ranged from 78.2% to 100%. Kappa statistic for each level ranged from 0.57 +/- 0.04 to 0.73 +/- 0.04, and for the highest level of processing evident it ranged from 0.52 +/- .04 to 0.58 +/- 0.04. ICC (2,1) for each level of cognitive processing ranged from 0.62 (F = 6.20; P = .000) to 1.00, and for the highest level of cognitive processing evident, it was 0.79 (F = 12.42; P = .000). Substantial to almost perfect agreement was attained. CONCLUSIONS: Reflective journals allow learners to revisit their experiences for critical analysis and deeper learning. This study describes a reliable method, based on Bloom's Taxonomy, of determining whether learners have achieved higher order thinking through reflective journal writing. This method can provide a baseline for facilitating higher order processing, critical thinking, and reflective practice. 相似文献
2.
Autoantibodies to the alpha/beta T-cell receptors in human immunodeficiency virus infection: dysregulation and mimicry.
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D F Lake S F Schluter E Wang R M Bernstein A B Edmundson J J Marchalonis 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(23):10849-10853
Autoimmune reactivity is a consequence of infection with human immunodeficiency virus (HIV). We studied serological cross-reactions of purified pooled IgG from sera of HIV-infected individuals by using nested sets of synthetic overlapping peptides duplicating the covalent structures of T-cell receptors (TCRs) and immunoglobulin light chains and report that two processes of autoantibody production occur. (i) IgG autoantibodies to putative regulatory variable domain CDR1 and FR3 epitopes (where CDR is complementarity-determining region and FR is framework region) are present in pooled IgG from HIV-infected individuals at levels 10-fold greater than that in pooled IgG from healthy humans. (ii) Anti-TCR autoimmunization involves antigenic mimicry between a conserved peptide stretch of the major neutralizing V3 loop determinant of HIV-1 gp120 and the conserved FR4 segment of the TCR V beta. Affinity-purified antibodies to the synthetic V3 loop peptide bound to a recombinant single-chain TCR and to a synthetic TCR joining segment peptide containing the FR4 sequence. Conversely, affinity-purified autoantibodies from pooled IgG from HIV-infected individuals to the TCR peptide bound the V3 loop peptide and a single-chain TCR. Inhibition studies indicated that the cross-reactive immunizing antigen was the V3 loop. These results bear upon the impact of HIV infection on immune regulation and on the selection of peptides for vaccine development. 相似文献
3.
Othman Shibly Robert E. Schifferle Sebastian G. Ciancio Majd Tarakji Maryanne L. Mather 《Journal of clinical periodontology》1997,24(4):260-263
Abstract A single blind 30 day study compared the reduction of plaque and gingivitis for the Hapika® Powerbrush to the Interplak® ultra 10 tuft. A longitudinal parallel group design was utilized and screening evaluation was performed to determine patient eligibility prior to study enrollment. 66 subjects were entered into the study and assigned to 1 of 2 groups, each using one of the toothbrushes. At baseline, subjects received an oral soft tissue exam, a dental hard tissue exam, and were scored by the Lobene modification of the Löe and Silness gingival index (GI). Plaque was then disclosed and scored both pre and post brushing using the modified Turesky plaque/debris examination and an interproximal bleeding examination was performed post-brushing. On days 15 and 30, after an oral soft tissue and GI examination, plaque was graded by the Modified Turesky plaque/debris exam. Subjects then brushed and were graded by the Modified Turesky plaque/debris examination and an interproximal bleeding index examination. The results showed that both brushes provided a similar change in clinical indices. All produced a statistically significant reduction from baseline to day 30 for the gingival index (26.5-29.1%), the bleeding index (13.8-24.1%), and the plaque index (16.9-19.4%), A comparison of pre and post brushing scores for the plaque index at 30 showed that both brushes reduced plaque similarly with a statistically significant reduction (P<0.05) from their pre-brushing plaque index scores at all time periods. 相似文献
4.
Justin C Wise Rose A Sevcik Robin D Morris Maureen W Lovett Maryanne Wolf 《J. Speech Lang. Hear. Res.》2007,50(4):1093-1109
PURPOSE: Some researchers (F. R. Vellutino, F. M. Scanlon, & M. S. Tanzman, 1994) have argued that the different domains comprising language (e.g., phonology, semantics, and grammar) may influence reading development in a differential manner and at different developmental periods. The purpose of this study was to examine proposed causal relationships among different linguistic subsystems and different measures of reading achievement in a group of children with reading disabilities. METHODS: Participants were 279 students in 2nd to 3rd grade who met research criteria for reading disability. Of those students, 108 were girls and 171 were boys. In terms of heritage, 135 were African and 144 were Caucasian. Measures assessing pre-reading skills, word identification, reading comprehension, and general oral language skills were administered. RESULTS: Structural equation modeling analyses indicated receptive and expressive vocabulary knowledge was independently related to pre-reading skills. Additionally, expressive vocabulary knowledge and listening comprehension skills were found to be independently related to word identification abilities. CONCLUSION: Results are consistent with previous research indicating that oral language skills are related to reading achievement (e.g., A. Olofsson & J. Niedersoe, 1999; H. S. Scarborough, 1990). Results from this study suggest that receptive and expressive vocabulary knowledge influence pre-reading skills in differential ways. Further, results suggest that expressive vocabulary knowledge and listening comprehension skills facilitate word identification skills. 相似文献
5.
Proposed definition of a smokeless tobacco user based on “potential” nicotine consumption 总被引:1,自引:0,他引:1
Kathleen L. Schroeder Moon S. Chen Jr. Gregory R. Iaderosa Elbert D. Glover Elizabeth W. Edmundson 《Addictive behaviors》1988,13(4):395-400
This study examined and operationally defined "light," "moderate," and "heavy" users of smokeless tobacco according to the potential amounts of nicotine consumed per week from chewing tobacco and/or snuff products. Fifty adult male smokeless tobacco users ranging in ages from 18-85 were tested to determine nicotine content of smokeless tobacco products consumed. The smokeless tobacco products were blindly analyzed by gas chromatography to determine nicotine content. Mean nicotine yield per week was calculated by multiplying the number of cans and/or pouches used per week and placed on a normal probability distribution. The mean nicotine yielded 238 mg/wk and the categories emerged as "light" less than or equal to 87 mg/wk, "moderate" 88-388 mg/wk and "heavy" users greater than or equal to 389 mg/wk. Differences regarding type of user (light, moderate, heavy) were crossed tabbed with educational levels, years of smokeless tobacco use, age the habit was initiated, perception of harm and whether habit forming, and reason for using smokeless tobacco. 相似文献
6.
Previous studies showed that the Mcg dimer of immunoglobulin light chains bound bis(dinitrophenyl)lysine both in trigonal crystals and in solution. On prolonged storage in ammonium sulfate, mixtures of ligand and protein produced small trigonal cocrystals in low frequency. These crystals were nearly isomorphous with those of the unliganded dimer in which the subunits were covalently linked by an interchain disulfide bond. By difference Fourier analyses at 3.5 A resolution and subsequent crystallographic refinement, the cocrystals were found to contain molecules with two ligands aligned in tandem along the interface of the variable (V) domains of the protein. One ligand molecule adopted an almost fully extended conformation, with the epsilon-DNP ring situated near the floor, the alpha-carboxyl group directed toward the solvent at the entry, and the alpha-DNP ring outside the rim of the main cavity. As if architecturally designed, the ligand was located symmetrically between the two domains in an orientation that was compatible with both the unaltered structure of the cavity lining and with the known crystal packing interactions of neighboring protein molecules. The second ligand molecule in the cocrystal lodged in the deep pocket immediately under the floor of the main cavity. The ligand adopted a very compact conformation with the two DNP rings roughly antiparallel to each other. This molecule appeared to be semi-permanently sequestered in the pocket since it could not be dislodged by exhaustive perfusion with ammonium sulfate crystallizing media. Relative to its volume in the native dimer, the pocket was expanded to accommodate the oversized ligand. Within a single protein molecule, therefore, two types of binding of a flexible ligand were observed, one with and one without accompanying conformational changes in the protein. The number of cocrystals which could be produced was markedly increased if the interchain disulfide bond between the Mcg monomers was first reduced and alkylated. 相似文献
7.
Tuberculosis (TB) in children requires close attention to infection control to prevent transmission to other patients and health care workers. Although many children with TB are not infectious, appropriate airborne precautions must be maintained until conditions that increase the risk of transmission have been ruled out and accompanying adults, who may also be infectious, have been screened. Concurrent strategies to prevent TB transmission should be implemented, including administrative, engineering and personal protective measures. The most important measure is maintaining a high clinical index of suspicion for TB in patients with compatible symptoms and epidemiological risk factors. Comprehensive tuberculin skin test programmes and the use of N 95 masks can reduce the risk of transmission within health care settings. Current standards of practice should be followed to prevent transmission from patients with active TB disease. 相似文献
8.
Thomas C Neylan Maryanne Lenoci Melissa L Maglione Nicholas Z Rosenlicht Thomas J Metzler Christian Otte Frank B Schoenfeld Rachel Yehuda Charles R Marmar 《Neuropsychopharmacology》2003,28(9):1666-1676
Metyrapone blocks cortisol synthesis, which results in the stimulation of hypothalamic cortiocotropin-releasing factor (CRF) and a reduction in delta sleep. We examined the effect of metyrapone administration on endocrine and sleep measures in male subjects with and without chronic PTSD. We hypothesized that metyrapone would result in a decrease in delta sleep and that the magnitude of this decrease would be correlated with the endocrine response. Finally, we utilized the delta sleep response to metyrapone as an indirect measure of hypothalamic CRF activity and hypothesized that PTSD subjects would have decreased delta sleep at baseline and a greater decrease in delta sleep induced by metyrapone. Three nights of polysomnography were obtained in 24 male subjects with combat-related PTSD and 18 male combat-exposed normal controls. On day 3, metyrapone was administered during normal waking hours until habitual sleep onset preceding night 3. Endocrine responses to metyrapone were measured in plasma obtained the morning following sleep recordings, the day before and after administration. Repeated measures ANOVAs were conducted to compare the endocrine and sleep response to metyrapone in PTSD and controls. PTSD subjects had significantly less delta sleep as indexed by stages 3 and 4, and total delta integrated amplitude prior to metyrapone administration. There were no differences in premetyrapone cortisol or ACTH levels in PTSD vs controls. PTSD subjects had a significantly decreased ACTH response to metyrapone compared to controls. Metyrapone caused an increase in awakenings and a marked decrease in quantitative measures of delta sleep that was significantly greater in controls compared to PTSD. The decline in delta sleep was significantly associated with the magnitude of increase in both 11-deoxycortisol and ACTH. The results suggest that the delta sleep response to metyrapone is a measure of the brain response to increases in hypothalamic CRF. These data also suggest that the ACTH and sleep EEG response to hypothalamic CRF is decreased in PTSD. 相似文献
9.
10.
Lisa Lieberman Una Diffley Sandy King Shelley Chanler Maryanne Ferrara Oscar Alleyne Joan Facelle 《American journal of public health》2013,103(11):1942-1948
In 2000, Rockland County, a small suburban county north of New York City, dedicated $1 million of its Master Settlement Agreement funds to a comprehensive tobacco control program, Put It Out Rockland. Developed and implemented by the county health department, this program used an essential public health services model and an ongoing financial investment, within the context of strong statewide tobacco control efforts, to lower adult smoking rates to 9.7% and to reduce both smoking among youths and exposure to secondhand smoke over the ensuing decade. By combining state funds and local dollars for a total of $6.75 cost per capita, this comprehensive effort yielded 11 000 fewer smokers and translated to a potential savings of more than $24 million for the county. 相似文献