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The light microscopic, immunohistological and ultrastructural findings in two cases of malignant fibrous histiocytoma arising in salivary glands are presented and the features of seven previously reported cases are reviewed. This neoplasm is extremely rare in this site and may pose problems in diagnosis. It has to be distinguished from other spindled cell tumours, in particular from epithelial tumours of predominantly spindled cell pattern; immunohistological markers for histiocytic cells may be of value. The histogenesis of this neoplasm is controversial but our electron microscopic findings support an origin from mesenchymal cells which differentiate along a broad fibrohistiocytic spectrum.  相似文献   
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Terrestrial risk assessments for pesticide exposure is generally based on a limited number of toxicity data. The protection target for these assessments requires an extrapolation from species for which toxicity data are available to other species with unknown sensitivity to be able to protect these as well. Our ability to extrapolate toxicity endpoints between species is a major source of uncertainty in risk assessment. Most analyses of interspecies extrapolation in avian risk assessments have dealt with acute toxicity data. It was suggested that, in the absence of a strong rationale to the contrary, we should assume that reproductive data is at least as variable as acute data and that strategies developed for acute data could be applied to long term toxicity data as well. Considering only the two main bird test species for which reproduction data are available (Mallard and Northern Bobwhite), a comparison of the interspecies standard deviation for both acute and reproduction data suggests that the two are equally variable. Analysis of a very limited data set also suggests that this conclusion holds regardless of which endpoint is triggered in the reproduction study. However, the relative sensitivity of the two species established from acute test data appears to be reversed in the case of reproductive data. In addition there seems to be no reason to believe that bodyweight is a factor in helping birds cope with the rigours of chronic dosing, which is in contrast with the acute dosing situation. This suggests that the best extrapolation technique for reproduction test data should be independent of phylogeny and independent of bodyweight scaling. The simplest such method is the one that was proposed by Luttik and Aldenberg (1995, 1997) for both birds and mammals.  相似文献   
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We report a case of appendiceal intussusception which was erroneously labelled as a 10-mm polypoid caecal lesion on colonoscopy and, therefore, followed up over an 11-year period before the correct diagnosis was made. We present the radiological and endoscopic appearance of appendiceal intussusception and a review of the literature.  相似文献   
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Aim:  To study CRP values and relate it to outcome in infants with antenatal diagnosis of gastroschisis, exomphalos and other surgical conditions.
Methods:  Over five years, infants admitted to our neonatal unit with gastroschisis, exomphalos and other surgical diagnoses were identified. Serum CRP measurements in first 5 days were studied. Group one included 33 gastroschisis patients, group two, 18 exomphalos patients, and group three, 38 patients with other surgical diagnoses. Outcome measures included TPN days, time to full feeds and duration of hospitalization.
Results:  Infants with gastroschisis were more premature (36.9 vs 38.1 weeks) with lower birth weights (2515 vs 3078 g), than infants with exomphalos. CRP values on admission in gastroschisis group were significantly higher than exomphalos and other diagnoses groups (33.7 ± 6.4 vs 8.8 ± 6.0 vs 5.7 ± 2.0, respectively, p   <   0.05). All blood cultures were sterile. There was no relationship between high CRP and death or adverse outcome (TPN days, time to full feeds or duration of hospitalization) in the gastroschisis group.
Conclusion:  Infants with gastroschisis exhibit high early CRP, which may not indicate sepsis or adverse outcome. This increase can complicate the assessment of these infants. Clinicians should be aware of this finding as it could inform management decisions in this group.  相似文献   
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Insulin is a polypeptide hormone that is present in mammals and its main function is the maintenance of adequate blood sugar level. Insulin receptors are widely but unevenly distributed in the brain. Insulin has been reported to be involved in the regulation of neurotransmitters release. It has also been linked to the pathogenesis of neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. Although there is abundant literature on the study of biochemical and molecular properties of insulin, there has been no literature on its central behavioural effects on anxiety and pain relief among other behavioural effects. This study therefore investigates whether insulin has any anxiolytic and other CNS effects. This experiment was carried out in mice using animal behavioural models including a hot plate analgesic test, holeboard and elevated plus maze for anxiolytic test. A Y-maze was used for the locomotor activity and spontaneous alternation investigations. Mice were administered intraperitoneally with insulin at different doses of 0.5, 1.0 and 2.0IU/kg. The results obtained showed that insulin has no analgesic activity, however, it caused significant central inhibitory effects by decreasing both locomotor activity in both holeboard and Y-maze models and also decreased the exploratory behaviour in holeboard at doses administered dose-dependently indicating its sedative effects. In elevated plus maze, insulin had no effects on percentage of open arm entries at all doses but had a significant effect on percentage of open arm duration at the dose of 1.0IU/kg only. Insulin administration at lower doses (0.5 and 1.0IU/kg, i.p.) had no effect on spatial working memory, however, it had significant spatial working memory impairment at the dose of 2.0IU/kg, i.p. in mice. The study showed that insulin has several neuropharmacological effects at doses used.  相似文献   
100.

Background  

In primary care, up to 74% of physical symptoms is classified as unexplained. These symptoms can cause high levels of distress and healthcare utilization. Cognitive behavioral therapy has shown to be effective, but does not seem to be attractive to patients. An exception herein is a therapy based on the consequences model, which distinguishes itself by its labeling of psychosocial distress in terms of consequences rather than as causes of physical symptoms. In secondary care, 81% of the patients accepts this therapy, but in primary care the outcome is poor. We assume that positive outcome can also be reached in primary care, when the consequences model is modified and used bottom-up in an easily accessible group training, in which patients are relieved of being blamed for their symptoms. Our aim is to investigate the (cost-)effectiveness of this training.  相似文献   
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