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1.
In an independent learning project, 52 third-year medical students carried out a structured self-assessment of two videotaped psycho-social interviews they had conducted with volunteer clients 1 year earlier, as part of a previous course. The interviews had been conducted in small tutorials with feedback from their clients, fellow students and tutors, facilitated by videotape playback. During the sequence of 16 tutorials each student had carried out an early and a late interview and had observed and participated in the discussion of the interviews of 14 peers. Students were asked to tally the frequencies of various interview behaviours, to evaluate the quality of their behaviours, and to establish priorities for future learning. The videotapes were also reliably rated by an independent observer. Students' overall self-assessments correlated 0.46 with those of the independent observer. This correlation was higher than is typically reported in studies of the validity of self-assessment. In absolute terms, the students' mean rating of interviewing performance was 3.2 (adequate plus) which was significantly lower than the observer's mean of 3.6 (adequate to good). Results are discussed in terms of Gordon's (1992) two recommendations for improving the validity of self-assessments and two further suggestions, for paired comparisons and low-threat learning environments, are added. 相似文献
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Malignant granular cell tumor of the lateral femoral cutaneous nerve: report of a case with cytogenetic analysis 总被引:5,自引:0,他引:5
Di Tommaso L Magrini E Consales A Poppi M Pasquinelli G Dorji T Benedetti G Baccarini P 《Human pathology》2002,33(12):1237-1240
Malignant granular cell tumors (MGCTs) are rare neoplasms of uncertain histogenesis. We report a case of MGCT involving a peripheral nerve with peritoneal and omental dissemination in which cytogenetic findings are available. Our results show that MGCTs share some cytogenetic abnormalities with malignant peripheral nerve sheath tumors (MPNSTs), supporting the hypothesis that they may represent histogenetically related lesions. 相似文献
4.
Modulation of anti-Candida activity of human alveolar macrophages by interferon-gamma or interleukin-1-alpha 总被引:9,自引:0,他引:9
A Vecchiarelli T Todisco M Puliti M Dottorini F Bistoni 《American journal of respiratory cell and molecular biology》1989,1(1):49-55
The fungicidal and bactericidal activities of human alveolar macrophages (AM) and peripheral blood monocytes (PBM) from 18 healthy volunteers were evaluated. The results showed that AM were able to phagocytize and kill Candida albicans, Pseudomonas aeruginosa, and Staphylococcus aureus. However, killing of the bacteria was already complete in 2 h, whereas killing of Candida required 4 to 6 h despite an early phagocytosis of yeast cells. The fungicidal activity of freshly collected AM and PBM was also tested after effector cell exposure to interferon-gamma (IFN-gamma), interleukin-1-alpha (IL-1 alpha), endotoxin lipopolysaccharide (LPS), or interleukin 2 (IL-2). It was found that treatment with IFN-gamma, IL-1 alpha, or LPS significantly augmented macrophage and PBM candidacidal activity, whereas the addition of IL-2 was ineffective. We also evaluated killing of C. albicans by AM cultured in vitro for different times. While phagocytosis was apparently unaffected, the candidacidal activity progressively decreased over the in vitro culture period, an effect that was largely reversed by cell exposure to IFN-gamma, IL-1 alpha, or LPS. In an experimental model in which mice infected with an agerminative C. albicans strain (PCA-2) resisted lethal microbial challenge, freshly harvested AM showed increased cytotoxic activity to Aspergillus fumigatus in vitro as well as enhanced IL-1 production. In conclusion, present data confirm the crucial role of AM in the surveillance of bacterial and fungal infections and indicate that treatment of these cells with IFN-gamma or IL-1 alpha is able to enhance their antimicrobial capability. 相似文献
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The effect of nifedipine on esophageal symptoms was evaluated in 20 patients with primary esophageal motor disorders. The patients were randomized to receive nifedipine (10 mg t.i.d.) or placebo for two weeks, and then crossed over to receive the other medication. Ten patients had hypertensive lower esophageal sphincter, four had diffuse esophageal spasm, three had vigorous achalasia, two had "nutcracker esophagus," and one patient had achalasia. The score of chest pain or dysphagia was recorded on a scale of 0 to 10 during each study. The patients who received nifedipine improved significantly compared to those who received placebo. This improvement was most marked in patients with hypertensive lower esophageal sphincter. No significant side effects or changes in blood pressure were encountered in any of the study groups. Our results indicate that patients with primary esophageal motor disorders have a good clinical response to nifedipine therapy. 相似文献
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Luigi Gennari Daniela Merlotti Natale Figura Christian Mingiano Maria Beatrice Franci Barbara Lucani Tommaso Picchioni Mario Alessandri Maria Stella Campagna Sara Gonnelli Simone Bianciardi Maria Materozzi Carla Caffarelli Stefano Gonnelli Ranuccio Nuti 《Journal of bone and mineral research》2021,36(1):80-89
Helicobacter pylori (HP) infection is a common and persistent disorder acting as a major cofactor for the development of upper gastrointestinal diseases and several extraintestinal disorders including osteoporosis. However, no prospective study assessed the effects of HP on bone health and fracture risk. We performed a HP screening in a population-based cohort of 1149 adults followed prospectively for up to 11 years. The presence of HP infection was assessed by serologic testing for serum antibodies to HP and the cytotoxin associated gene-A (CagA). The prevalence of HP infection did not differ among individuals with normal bone mineral density (BMD), osteoporosis, and osteopenia. However, HP infection by CagA-positive strains was significantly increased in osteoporotic (30%) and osteopenic (26%) patients respect to subjects with normal BMD (21%). Moreover, anti-CagA antibody levels were significantly and negatively associated with lumbar and femoral BMD. Consistent with these associations, patients affected by CagA-positive strains had a more than fivefold increased risk to sustain a clinical vertebral fracture (HR 5.27; 95% CI, 2.23–12.63; p < .0001) and a double risk to sustain a nonvertebral incident fracture (HR 2.09; 95% CI, 1.27–2.46; p < .005). Reduced estrogen and ghrelin levels, together with an impaired bone turnover balance after the meal were also observed in carriers of CagA-positive HP infection. HP infection by strains expressing CagA may be considered a risk factor for osteoporosis and fractures. Further studies are required to clarify in more detail the underlying pathogenetic mechanisms of this association. © 2020 American Society for Bone and Mineral Research (ASBMR). 相似文献
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Early MRI findings in Creutzfeldt-Jakob disease 总被引:1,自引:0,他引:1
Marco Onofrj Tommaso Fulgente Domenico Gambi Giorgio Macchi 《Journal of neurology》1993,240(7):423-426
We describe the MRI changes preceding the onset of myoclonus in two patients whose post-mortem examination confirmed the diagnosis of Creutzfeldt-Jakob disease (CJD). MRI showed changes in the striatum early in the course of CJD (2–6 months after the onset of apathy, interpreted as depression, and 1–2 months before the onset of further clinical symptoms). Only in one patient did electroencephalography record the typical triphasic sharp-waves, 1 month after MRI. 相似文献
8.
Soluble CD40 ligand plasma levels in lung cancer. 总被引:7,自引:0,他引:7
Mario Roselli Tommaso C Mineo Stefania Basili Francesca Martini Sabrina Mariotti Simona Aloe Girolamo Del Monte Vincenzo Ambrogi Antonella Spila Raffaele Palmirotta Roberta D'Alessandro Giovanni Davì Fiorella Guadagni Patrizia Ferroni 《Clinical cancer research》2004,10(2):610-614
PURPOSE: Tumor-induced platelet activation may cause the release of various cytokines, including CD40 ligand (CD40L). Activation of the CD40/CD40L pathway in human tumors may result in thrombin generation, which is known to be involved in angiogenesis. Thus, we investigated whether soluble (s)CD40L levels are increased in patients with lung cancer as a result of platelet and/or coagulation activation. EXPERIMENTAL DESIGN: Citrated plasma samples were obtained from 120 patients with different stages and histotypes of lung cancer and 60 age- and sex-matched control subjects. sCD40L, sP-selectin (marker of platelet activation), prothrombin fragment 1 + 2, and thrombin-antithrombin III complex levels (both markers of coagulative activation) were measured in all samples. RESULTS: Patients with lung cancer had median sCD40L levels higher than in control subjects (0.46 versus 0.13 ng/ml; P < 0.0001), although correlation with the stage of disease was not evident. Nonetheless, sCD40L levels were significantly higher in squamous cancer compared with adenocarcinoma (0.75 versus 0.27 ng/ml; P < 0.05). Moreover, median sCD40L levels were higher in stage IV compared with nonmetastatic squamous lung cancer (1.02 versus 0.61 ng/ml; P < 0.05). sCD40L levels significantly correlated with sP-selectin (P < 0.001), prothrombin fragment 1 + 2 (P < 0.001), or thrombin-antithrombin III complex (P < 0.05) in squamous lung cancer, but only sP-selectin (P = 0.011) was independently related to sCD40L. CONCLUSIONS: These findings indicate that elevated sCD40L levels can be preferentially found in patients with advanced squamous cancer and provide evidence that increased levels of this cytokine are associated to the occurrence of in vivo platelet activation. 相似文献
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