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1.
Rebecca L. King Albert C. Yan Debora R. Sekiguchi John K. Choi 《Journal of cutaneous pathology》2015,42(12):1012-1017
Reactive lymphoid infiltrates of the skin composed predominantly of gamma‐delta (γδ) T cells are not well described in the literature. Herein we report a case of an otherwise healthy 4‐year‐old male who presented with a waxing and waning papular rash characterized by small, discrete crusted papules spread across his trunk, face and extremities. Clinical evaluation revealed no evidence of systemic disease. Microscopic examination revealed a dermal, perivascular infiltrate of highly atypical lymphocytes with a γδ T cell phenotype, worrisome for primary cutaneous γδ T cell lymphoma. The clinical course, however, was that of a reactive condition and prompted consideration of a diagnosis of pityriasis lichenoides et varioliformis acuta (PLEVA) and lymphomatoid papulosis (LyP). In many ways, this case defies current classification schemes and seems to expand the spectrum of reactive γδ T cell infiltrates of the skin. 相似文献
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Cesar G. Victora Nubia Muoz Nicholas E. Day Lucio B. Barcelos Debora A. Peccin Noris M. Braga 《International journal of cancer. Journal international du cancer》1987,39(6):710-716
There is a cluster of high-incidence areas of oesophageal cancer in south-eastern South America, including Southern Brazil, Uruguay and parts of Argentina. The present case-control study investigated the hypothesis that this may be due to the drinking of maté, a traditional beverage drunk at a very high temperature, and also studied the role of other known risk factors such as alcohol and tobacco. Cases (171) and age- and sex-matched controls (342) were recruited from hospitals in the State of Rio Grande do Sul in Southern Brazil. The crude odds ratio for daily maté drinkers was 1.92 relative to those drinking less frequently than daily (p = 0.006). Other risk factors included the drinking of cachaça (a sugar cane spirit), smoking, rural residence, low fruit consumption and high intake of meats. After adjustment for these variables through conditional logistic regression, the odds ratio associated with daily maté drinking was reduced to 1.47 (90% CI = 0.87 - 2.50). Although the study failed to provide evidence of a strong association between maté and oesophageal cancer, the cluster of high rates could be explained by relative risks of the magnitude observed. This is due to the fact that approximately 70% of adult males and 50% of females are daily drinkers. In addition, this study revealed that alcohol, tobacco smoking and rural residence are the main risk factors for oesophageal cancer in this population and the fruit consumption confers some degree of protection. 相似文献
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L. Marzio F. Di Felice V. Celiberti O. Pieramico L. Grossi M. DiGioacchino B. P. Imbimbo F. Cuccurullo 《European journal of clinical pharmacology》1990,39(4):369-372
Summary To evaluate the influence of the stomach and the cholinergic system on gallbladder contraction induced by physiological stimuli, the reduction in gallbladder volume in 7 healthy volunteers has been studied by real-time ultrasonography after the oral and intraduodenal administration of olive oil, preceded by pretreatment with cimetropium bromide or placebo. After an overnight fast, each subject swallowed 50 ml olive oil or it was administered through a naso-duodenal tube in the proximal duodenum. Cimetropium bromide 5 mg or placebo was given intravenously under double-blind control.After the placebo pretreatment, gallbladder contraction was greater and faster after intraduodenal oil than after oral oil. Cimetropium bromide decreased the extent, velocity and duration of gallbladder contraction induced by intraduodenal olive oil but it only reduced the velocity of the contraction induced by oil given orally.It is concluded that in normal human subjects the stomach modulates the extent and velocity of postprandial gallbladder contraction and that anticholinergic agents antagonize the gastric and duodenal phases of the response of the gallbladder to a meal. 相似文献
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M Napolitano M Durante G F Grossi M Pugliese G Gialanella 《International journal of radiation biology》1992,61(6):813-820
Inactivation of mouse C3H 10T1/2 cells in plateau-phase (7.8 x 10(4) cells/cm2) was studied by using alpha-particles from the irradiation facility installed for radiobiological experiments at the 3 MV Tandem accelerator, University of Naples. Silicon detectors and CR39 plastic track detectors were employed for dosimetric purposes. The cells were exposed to high LET monoenergetic alpha-particles (energy of 1.8 MeV at the centre of the cell nucleus, track-averaged LET of 177 keV/micron and dose-rate of 1.1 Gy/min) and low-LET 80 kVp X-rays. The X-ray survival curve showed a significant shoulder (alpha/beta = 9 Gy) while the survival curve for alpha-particles was close to exponential. The mean lethal dose of alpha-particles was 0.77 +/- 0.02 Gy and the RBE was 5.2 at 80% survival and 3.0 at 5% survival. Survival of exponentially growing cells (2 x 10(4) cells/cm2) following irradiation with the alpha-particle beam is also reported. The nuclear areas of 10T1/2 cells were measured as 299 +/- 9 micron 2 and 250 +/- 8 micron 2 for cells in log phase and plateau phase, respectively. The inactivation cross-section, obtained from the mean lethal dose, was 34 micron 2 and 37 micron 2 for cells in log phase and plateau phase, respectively. These values appear to be the maximum measured values for the inactivation cross-section of 10T1/2 cells as a function of the alpha-particle LET. This saturation cross-section is very similar to the saturation values reported in the literature for other mammalian cell lines. 相似文献
8.
The 5-HT1 agonist sumatriptan (SUM) elicits an increase in amplitude of oesophageal motor waves and of lower oesophageal sphincter (LOS) tone in healthy subjects. The aim of the study was to evaluate whether such an effect occurs also in patients with ineffective oesophageal motility (IOM). 16 patients (nine males and seven females, age range 34-55 years) with chest pain and mild to moderate dysphagia were studied; all had undergone previous cardiologic, radiologic and upper gastrointestinal endoscopic exams that were normal. An oesophageal manometry was performed using an electronic probe to record swallows, oesophageal, LOS and gastric motility. The patients whose motor pattern were compatible with IOM (>30% of motor waves with amplitude <30 mmHg and/or non-transmitted) received SUM or placebo 6 mg s.c., injected in the morning and in the afternoon in a random order. The data analysis was limited to 1 h before and 1 h after the drug injections. Ten out of the 16 patients showed an IOM motor pattern. The administration of SUM caused a significant increase in the number of swallows (SUM 99.5 +/- 15.4 vs 78.6 +/- 16.1 basal, P = 0.03) and of primary oesophageal motor waves (SUM 89.6 +/- 13.4 vs 67.2 +/- 12.9 basal, P = 0.04) with no significant changes in the percentage of swallows associated with propagation. Placebo was not associated with increase in the number of swallows (80.3 +/- 14.6, P = 0.9) or of primary oesophageal motor waves (70.1 +/- 12.3, P = 0.7). The amplitude and the percentage of propagated oesophageal motor waves as well as the mean basal LOS tone were unaltered by SUM. There was no change in the symptoms reported after SUM. Although effective in healthy subjects, SUM 6 mg s.c. improves only the numbers but not the amplitude or propagation of oesophageal motility of patients with IOM. The 5-HT1 pathway and its acute stimulation seem to play only a minor role in the pathogenesis of such a disease. 相似文献
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Alberto Falchetti Marco Di Stefano Francesca Marini Francesca Del Monte Carmelo Mavilia Debora Strigoli Maria L De Feo Giovan Isaia Laura Masi Antonietta Amedei Federica Cioppi Valentina Ghinoi Susanna Maddali Bongi Giuseppina Di Fede Carmela Sferrazza Giovan B Rini Daniela Melchiorre Marco Matucci-Cerinic Maria L Brandi 《Journal of bone and mineral research》2004,19(6):1013-1017
PDB is genetically heterogeneous. Mutations of the sequestosome1 gene have been reported in sporadic and familial forms of Paget's in patients of French Canadian and British descent. Mutational analyses in different ethnic groups are needed to accurately investigate hereditary diseases. We describe two novel mutations of sequestosome1 in 62 Italian sporadic patients, confirming the role of the encoded protein in this disorder. INTRODUCTION: Paget's disease of bone (PDB) is a relatively common disease of bone metabolism reported to affect up to 3% of whites over 55 years of age. The disorder is genetically heterogeneous, and at present, there is scientific evidence that at least eight different human chromosomal loci are correlated with its pathogenesis. Mutations of the sequestosome1 (SQSTM1) gene were identified as responsible for most of the sporadic and familial forms of Paget in patients of French Canadian and British descent. Such mutations were located at exon 7 and 8 levels, encoding for the ubiquitin protein-binding domain (UBA) and representing a mutational hot spot area. MATERIALS AND METHODS: To verify the involvement of this gene in Italian subjects affected by PDB, we performed mutational analysis in 62 sporadic PDB cases. RESULTS: We described three different mutations at exon 8 level: P392L, already described in the French Canadian population and families predominantly of British descendent, and two novel mutations consisting of the amino acid substitutions M404V and G425R. No significant differences in the clinical history of PDB have been observed in patients with SQSTM1 mutations in respect to those without. CONCLUSIONS: Even though our findings suggest a minor involvement of the SQSTM1 gene in the pathogenesis of sporadic Italian Paget's cases, the identification of different significant mutations within the SQSTM1 gene in unrelated, but clinically similar individuals, offers extremely convincing evidence for a causal relationship between this gene and PDB. Longitudinal studies are needed to assess the penetrance of genotype/phenotype correlations. Our findings confirm the evidence of a clustered mutation area at this level in this disorder. 相似文献