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51.
Context
Medical educational reform includes enhancing role modelling of clinical teachers. This requires faculty being aware of their role model status and performance. We developed the System for Evaluation of Teaching Qualities (SETQ) to generate individualized feedback on previously defined teaching qualities and role model status for faculty in (non) academic hospitals.Objectives
(i) To examine whether teaching qualities of faculty were associated with their being seen as a specialist role model by residents, and (ii) to investigate whether those associations differed across residency years and specialties.Methods & Materials
Cross-sectional questionnaire survey amongst 549 Residents of 36 teaching programs in 15 hospitals in the Netherlands. The main outcome measure was faculty being seen as specialist role models by residents. Statistical analyses included (i) Pearson''s correlation coefficients and (ii) multivariable logistic generalized estimating equations to assess the (adjusted) associations between each of five teaching qualities and ‘being seen as a role model’.Results
407 residents completed a total of 4123 evaluations of 662 faculty. All teaching qualities were positively correlated with ‘being seen as a role model’ with correlation coefficients ranging from 0.49 for ‘evaluation of residents’ to 0.64 for ‘learning climate’ (P<0.001). Faculty most likely to be seen as good role models were those rated highly on ‘feedback’ (odds ratio 2.91, 95% CI: 2.41–3.51), ‘a professional attitude towards residents’ (OR 2.70, 95% CI: 2.34–3.10) and ‘creating a positive learning climate’ (OR 2.45, 95% CI: 1.97–3.04). Results did not seem to vary much across residency years. The relative strength of associations between teaching qualities and being seen as a role model were more distinct when comparing specialties.Conclusions
Good clinical educators are more likely to be seen as specialist role models for most residents. 相似文献52.
The spores of Anabaena doliolum formed in light (light spores)and after transfer to darkness (dark spores) are biochemicallydifferent in that the light spores contain chlorophyll a andphycocyanin, while dark spores seem to lack them. The apparentbiosyntheses accompanying dark-spore germination seem to proceedin the following order: RNA, chlorophyll a, phycocyanin andDNA. Results of chloramphenicol treatment indicate that proteinsynthesis precedes RNA synthesis. The biosynthetic events followingRNA synthesis show a requirement for light. 相似文献
53.
Evolutionary transfer of ORF-containing group I introns between different subcellular compartments (chloroplast and mitochondrion) 总被引:10,自引:2,他引:8
Turmel M; Cote V; Otis C; Mercier JP; Gray MW; Lonergan KM; Lemieux C 《Molecular biology and evolution》1995,12(4):533-545
We describe here a case of homologous introns containing homologous open
reading frames (ORFs) that are inserted at the same site in the large
subunit (LSU) rRNA gene of different organelles in distantly related
organisms. We show that the chloroplast LSU rRNA gene of the green alga
Chlamydomonas pallidostigmatica contains a group I intron (CpLSU.2)
encoding a site-specific endonuclease (I-CpaI). This intron is inserted at
the identical site (corresponding to position 1931-1932 of the Escherichia
coli 23S rRNA sequence) as a group I intron (AcLSU.m1) in the mitochondrial
LSU rRNA gene of the amoeboid protozoon Acanthamoeba castellanii. The
CpLSU.2 intron displays a remarkable degree of nucleotide similarity in
both primary sequence and secondary structure to the AcLSU.m1 intron;
moreover, the Acanthamoeba intron contains an ORF in the same location
within its secondary structure as the CpLSU.2 ORF and shares with it a
strikingly high level of amino acid similarity (65%; 42% identity). A
comprehensive survey of intron distribution at site 1931 of the chloroplast
LSU rRNA gene reveals a rather restricted occurrence within the
polyphyletic genus Chlamydomonas, with no evidence of this intron among a
number of non- Chlamydomonad green algae surveyed, nor in land plants. A
parallel survey of homologues of a previously described and similar
intron/ORF pair (C. reinhardtii chloroplast CrLSU/A. castellanii
mitochondrial AcLSU.m3) also shows a restricted occurrence of this intron
(site 2593) among chloroplasts, although the intron distribution is
somewhat broader than that observed at site 1931, with site-2593 introns
appearing in several green algal branches outside of the Chlamydomonas
lineage. The available data, while not definitive, are most consistent with
a relatively recent horizontal transfer of both site-1931 and site- 2593
introns (and their contained ORFs) between the chloroplast of a
Chlamydomonas-type organism and the mitochondrion of an Acanthamoeba- like
organism, probably in the direction chloroplast to mitochondrion. The data
also suggest that both introns could have been acquired in a single event.
相似文献
54.
Singaram?Gopalakrishnan Napo?KM?Cheung Bill?WP?Yip Doris?WT?AuEmail author 《Frontiers in zoology》2013,10(1):78
Introduction
Females having a longer telomere and lifespan than males have been documented in many animals. Such linkage however has never been reported in fish. Progressive shortening of telomere length is an important aging mechanism. Mounting in vitro evidence has shown that telomere shortening beyond a critical length triggered replicative senescence or cell death. Estrogen has been postulated as a key factor contributing to maintenance of telomere and sex-dependent longevity in animals. This postulation remains unproven due to the lack of a suitable animal system for testing. Here, we introduce a teleost model, the Japanese medaka Oryzias latipes, which shows promise for research into the molecular mechanism(s) controlling sex difference in aging.Results
Using the medaka, we demonstrate for the first time in teleost that (i) sex differences (female?>?male) in telomere length and longevity also exist in fish, and (ii) a natural, ‘menopause’-like decline of plasma estrogen was evident in females during aging. Estrogen levels significantly correlated with telomerase activity as well as telomere length in female organs (not in males), suggesting estrogen could modulate telomere length via telomerase activation in a sex -specific manner. A hypothetical in vivo ‘critical’ terminal restriction fragment (TRF, representing telomere) length of approximately 4 kb was deduced in medaka liver for prediction of organismal mortality, which is highly comparable with that for human cells. An age conversion model was also established to enable age translation between medaka (in months) and human (in years). These novel tools are useful for future research on comparative biology of aging using medaka.Conclusion
The striking similarity in estrogen profile between aging female O. latipes and women enables studying the influence of “postmenopausal” decline of estrogen on telomere and longevity without the need of invasive ovariectomy. Medaka fish is advantageous for studying the direct effect of increased estrogen on telomere length and longevity without the breast cancer complications reported in rodents. The findings strongly support the notion that O. latipes is a unique non-mammalian model for validation of estrogenic influence on telomere and longevity in vertebrates. This laboratory model fish is of potential significance for deciphering the ostensibly conserved mechanism(s) of sex-associated longevity in vertebrates.55.
Benjamin C. M. Boerebach Kiki M. J. M. H. Lombarts Albert J. J. Scherpbier Onyebuchi A. Arah 《PloS one》2013,8(7)
Background
In fledgling areas of research, evidence supporting causal assumptions is often scarce due to the small number of empirical studies conducted. In many studies it remains unclear what impact explicit and implicit causal assumptions have on the research findings; only the primary assumptions of the researchers are often presented. This is particularly true for research on the effect of faculty’s teaching performance on their role modeling. Therefore, there is a need for robust frameworks and methods for transparent formal presentation of the underlying causal assumptions used in assessing the causal effects of teaching performance on role modeling. This study explores the effects of different (plausible) causal assumptions on research outcomes.Methods
This study revisits a previously published study about the influence of faculty’s teaching performance on their role modeling (as teacher-supervisor, physician and person). We drew eight directed acyclic graphs (DAGs) to visually represent different plausible causal relationships between the variables under study. These DAGs were subsequently translated into corresponding statistical models, and regression analyses were performed to estimate the associations between teaching performance and role modeling.Results
The different causal models were compatible with major differences in the magnitude of the relationship between faculty’s teaching performance and their role modeling. Odds ratios for the associations between teaching performance and the three role model types ranged from 31.1 to 73.6 for the teacher-supervisor role, from 3.7 to 15.5 for the physician role, and from 2.8 to 13.8 for the person role.Conclusions
Different sets of assumptions about causal relationships in role modeling research can be visually depicted using DAGs, which are then used to guide both statistical analysis and interpretation of results. Since study conclusions can be sensitive to different causal assumptions, results should be interpreted in the light of causal assumptions made in each study. 相似文献56.
M Morgan Conn Joe Kappock Dale Drueckhammer Richard Cammack Dennis Hall Tony Cass Jon D Stewart Graham RL Cousins Jeremy KM Sanders Sabine Flitsch Philip AS Lowden Richard Newman 《Current opinion in chemical biology》1999,3(6):631
A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in chemical biology. 相似文献
57.
KM Abha Mishra Runesh Podili Teja S. Pathlavath Kalyan K. Sethi 《Journal of biochemical and molecular toxicology》2023,37(8):e23409
Since the outbreak of highly virulent coronaviruses, significant interest was assessed to the brain and heart axis (BHA) in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-affected patients. The majority of clinical reports accounted for unusual symptoms associated with SARS-CoV-2 infections which are of the neurological type, such as headache, nausea, dysgeusia, anosmia, and cerebral infarction. The SARS-CoV-2 enters the cells through the angiotensin-converting enzyme (ACE-2) receptor. Patients with prior cardiovascular disease (CVD) have a higher risk of COVID-19 infection and it has related to various cardiovascular (CV) complications. Infected patients with pre-existing CVDs are also particularly exposed to critical health outcomes. Overall, COVID-19 affected patients admitted to intensive care units (ICU) and exposed to stressful environmental constraints, featured with a cluster of neurological and CV complications. In this review, we summarized the main contributions in the literature on how SARS-CoV-2 could interfere with the BHA and its role in affecting multiorgan disorders. Specifically, the central nervous system involvement, mainly in relation to CV alterations in COVID-19-affected patients, is considered. This review also emphasizes the biomarkers and therapy options for COVID-19 patients presenting with CV problems. 相似文献
58.