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1.
Clinical and histological patterns of dermatofibromas of the nail apparatus   总被引:1,自引:0,他引:1  
True fibromas develop as painless slow-growing nodular tumours. They may appear in any portion of the nail apparatus. The clinical features vary according to their anatomical site. In contrast, the histological features, consisting of a dermal hypocellular reticular nodule with ill-defined demarcation, were similar in all our patients, and factor XIIIa was negative.  相似文献   
2.
Concept mapping is an instructional strategy that requires learners to identify, graphically display, and link key concepts in instructional reading material. Although proven effective in numerous disciplines as a means to promote critical thinking and self-directed learning, concept mapping has not been tested in diet therapy. The objective of this study was to implement concept mapping as a small-group, cooperative learning strategy in an upper-division diet therapy course and to evaluate student attitudes about the effect of concept mapping on knowledge, self-directed learning, problem-solving, and collaborative skills. Students in the first semester (n=27) initially learned course material by lecture (4 weeks) followed by an integrated mapping/lecture format (12 weeks); the second semester (n=25) used an integrated mapping lecture format for the full 16 weeks. At the end of both semesters, students completed a 10-item original survey questionnaire. Responses for first (n=25) and second (n=21) semesters were analyzed independently. Results indicated that a majority of students thought participation in concept mapping enhanced knowledge of diet therapy principles (n=19 of 25; 18 of 21), self-directed learning (n=14 of 25; 18 of 21), critical thinking (n=21 of 25; 14 of 21), problem-solving (n=22 of 25; 16 of 21), and collaboration (n=24 of 25; 20 of 21) skills. When noncooperation of teammates was a factor, concept mapping was viewed as more frustrating and time consuming than lecture. This study demonstrated concept mapping as an effective learning strategy for diet therapy; it improves students’ ability to engage in self-directed learning, critical thinking, collaboration, and creative problem solving. Results suggest that concept mapping is most effective when accompanied with comprehensive training, coordinated lectures, instructor guidance, and long-term practice. J Am Diet Assoc. 1995; 95:908–911.  相似文献   
3.
A method for the simultaneous determination of the ratios of the three aromatic amino-acid residues in peptides was set up in acidic conditions. Binary and ternary mixtures of these amino acids were prepared, and first- and second-derivative spectra then calculated from their 0.1 nm resolution spectra between 240 and 320 nm. Certain spectral bands were chosen to differentiate tyrosine from tryptophan on the first-derivative spectra, and phenylalanine from tyrosine and tryptophan on the second-derivative spectra. Variation of the amplitude of the chosen bands was shown to be a linear function of the ratio of the aromatic amino acids in the mixture. This technique was validated with peptides whose sequence was known. The difference between theoretical and experimentally determined ratios was lower than 10%. Since the results are obtained as ratios, neither the concentration nor the nature of the peptide has to be known. The feasibility of application using a photodiode array detector with high resolution in reversed-phase high-performance liquid chromatography is discussed. © Munksgaard 1995.  相似文献   
4.
5.
HEPATITIS C VIRUS AND ESSENTIAL MIXED CRYOGLOBULINAEMIA   总被引:2,自引:0,他引:2  
Clinical and laboratory evidence of liver involvement are frequentlyfound in essential mixed cryoglobulinaemia (EMC). We lookedfor evidence of hepatitis C virus (HCV) infection in 37 patientswith EMC. Anti-HCV antibodies (Ab) were found in 16/37 (43%)patients with EMC using the ELISA 2 test and the RIBA 2 test.The 16 anti-HCV-Ab positive patients (group 1) were comparedto the 21 anti-HCV-Ab negative patients (group 2). Group 1 patientshad more frequent cutaneous involvement (P = 0.02), clinical,biological and histologic hepatic involvement (P<0.01), higherserum cryoglobulin and lower CH50 levels (P<0.001). Serumhepatitis B virus markers were infrequent in both groups andno patient from either group had detectable serum HBV DNA. Thesepreliminary results suggest that HCV may be another cause ofmixed cryoglobulinaemia. KEY WORDS: Hepatitis C virus, Cryoglobulinaemia  相似文献   
6.
In the diagnostic work‐up of hypersomnias of central origin, the complaint of excessive daytime sleepiness should be objectively confirmed by MSLT findings. Indeed, the features and diagnostic utility of spontaneous daytime sleep at 24 h continuous polysomnography (PSG) have never been investigated. We compared daytime PSG features to MSLT data in 98 consecutive patients presenting with excessive daytime sleepiness and with a final diagnosis of narcolepsy with cataplexy/hypocretin deficiency (n = 39), narcolepsy without cataplexy (n = 7), idiopathic hypersomnia without long sleep time (n = 19), and ‘hypersomnia’ with normal sleep latency at MSLT (n = 33). Daytime sleep time was significantly higher in narcolepsy‐cataplexy but similar in the other groups. Receiver operating characteristics (ROC) curves showed that the number of naps during daytime PSG predicted a mean sleep latency ≤8 min at MSLT with an area under the curve of 0.67 ± 0.05 (P = 0.005). The number of daytime sleep‐onset REM periods (SOREMPs) in spontaneous naps strikingly predicted the scheduled occurrence of two or more SOREMPs at MSLT, with an area under the ROC curve of 0.93 ± 0.03 (P < 10?12). One spontaneous SOREMP during daytime had a sensitivity of 96% with specificity of 74%, whereas two SOREMPs had a sensitivity of 75%, with a specificity of 95% for a pathological REM sleep propensity at MSLT. The features of spontaneous daytime sleep well correlated with MSLT findings. Notably, the occurrence of multiple spontaneous SOREMPs during daytime clearly identified patients with narcolepsy, as well as during the MSLT.  相似文献   
7.
International Journal of Paediatric Dentistry 2010; 20: 366–373 Background. While dental anxiety is often correlated with prior negative dental experience, prevention of dental anxiety should in theory include early exposure to the dental setting. Objective. We set out to evaluate factors affecting dental fear in French children. Methods. Dental fear was evaluated using a visual analogue scale (DF‐VAS) in a group of 1303 French children (681 boys and 622 girls) aged 5–11 years (mean: 8.12 years, SD: 1.42 years). Indicators of caries and oral hygiene were evaluated on dental examination. Indicators of well‐being related to oral health, dental experience, and oral health education were collected via a structured interview. Results. Dental fear was scored low in 75.7% (DF‐VAS 0–3), moderate in 16.7% (DF‐VAS 4–6), and high in 7.6% (DF‐VAS 7–10). DF‐VAS decreased statistically with experience of a prior dental visit. Children who had at least one decayed tooth presented a higher level of dental fear than those with no decay, while children with fillings were significantly less anxious than those without previous dental care. Conclusions. This study shows that for children aged 5–12 years, prior experience of the dental setting can act as a positive component of dental fear.  相似文献   
8.
The first case of a patient with interrupted inferior vena cava, four post-renal veins and an azygoshemiazygos continuation is presented. The complicated anomalies were omphalocele and atrial septal defect. Cine-magnetic resonance imaging and cardiac catheterization showed an anomalous retroaortic left innominate vein, azygos-hemiazygos continuation in the prerenal portion, arch formed renal vein in the renal portion and four embryonic vessels in the post-renal portion. Combination of these anomalies in the major venous system suggested that the inferior vena cava had failed to form and that the bilateral embryonic venous system, postcardinal and supracardinal veins persisted to be the systemic venous channels.  相似文献   
9.
ABSTRACT. The symptoms of acute poisoning after accidental administration of ten times the usually prescribed dosage of caffeine in a premature infant included the following neurological signs: incessant tremors, hypertonia, continuous opisthotonos posture, whining and crying and digestive disturbances. The very high serum caffeine levels, 160 mg/l, determined 66 hours after the first administration was confirmed by the very high cerebrospinal fluid caffeine concentration 115 mg/l. Two exchange transfusions performed at an interval of 16 hours produced a large decrease in serum caffeine levels of approximately 40 mg/l each time, and a similar decrease in the cerebrospinal fluid concentration. The clinical status of the infant improved very rapidly and the child's psychomotor development was normal at 3 months of age.  相似文献   
10.
Pancreata of fetal, neonatal and adult cattle were studied immunohistochemically for galanin. The results revealed galanin-like immunoreactivity both in the endocrine cells and in the neural elements. The galanin-like immunoreactive endocrine cells (Gal-LIEC) were confined to the large islets, and were not observed in the islets of Langerhans and exocrine pancreas. They were first detected at the third prenatal month. Their developmental profile showed an increase from fetal to early neonatal stage with a subsequent decrease towards adulthood. The considerable number of Gal-LIEC from late prepartum to early postpartum stage may imply functional significance of galanin during the perinatal development of cattle. Coexistence of galanin and insulin was also observed which may suggest autocrine interaction between the 2 hormones.  相似文献   
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