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1.
Cystic fibrosis (CF) and Crohn's disease may both present as failure to thrive and recurrent intestinal obstruction. Proper treatment and adequate nutrition may reverse these manifestations and improve the patient's quality of life. We describe a girl with CF who, despite appropriate management, failed to grow and had several episodes of bowel obstruction. After the additional diagnosis of Crohn's disease was reached, the patient improved on antiinflammatory and nutritional therapy. This patient illustrates the pitfall in the diagnosis of Crohn's disease in a CF patient due to the clinical overlap between the two conditions. We suggest that therapeutic failure in a chronic disease justifies additional diagnostic efforts resulting in a completion of diagnosis and significant changes in management.  相似文献   
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Homozygote hypotransferrinaemic mice (hpx/hpx) have cytopathological features similar to those of human congenital atransferrinaemia, genetic haemochromatosis, and neonatal haemochromatosis. These conditions all have in common high levels of cytotoxic non-transferrin-bound serum iron. This study describes the ultrastructural features of iron overload in liver, pancreas, heart, and small intestine of 2- and 12-month-old hypotransferrinaemic mice. Electron microscopic studies of unstained sections showed early parenchymal cell siderosis, with accumulation of numerous ferritin particles and clusters in the cytosol, as well as ferritin and haemosiderin in lysosomes (siderosomes). In the 12-month-old animals, iron was also found in Kupffer cells and macrophages in other tissues. In addition, there were conspicuous iron-containing compounds in the bile canaliculi, and marked iron deposition in the pancreas and heart. Laser microprobe mass analysis (LAMMA) enabled localization and relative quantitation of iron deposition in subcellular compartments providing in situ documentation of iron accumulation in siderosomes and contributed in assessing total cytosolic iron in various cell types. Moreover, it demonstrated the importance and magnitude of the biliary route for iron excretion in these animals.  相似文献   
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Pigmentosis tubae (PT) is a rare condition characterized by the presence of numerous lipofuscin-laden macrophages in the lamina propria of the fallopian tube. Two women, who also had endometriotic ovarian cysts, showed polypoid pigmented tubal mucosae. In addition to lipofuscin, occasional cells showed spotty positivity for iron. Ultrastructural examination of the tubal mucosa showed the lipofuscin-containing bodies, which were similar to lipofuscin-containing lysosomes found in other pigmented conditions. Cytoplasmatic ferritin and hemosiderin in siderosomes were observed in macrophages and endothelial cells of the lamina propria. The present study is the first to demonstrate the presence of iron-containing particles and lipofuscin in the residual bodies of PT. The origin of the excess iron is not clear, but erythrophagocytosis and an abnormal tubal environment could play a role. Iron-promoted lipid peroxidation may alter the lysosomal membranes and contribute to the excessive accumulation of lipofuscin in these cells.  相似文献   
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Hepatic iron content was determined in post mortem specimens from a wide range of avian species collected over a 12-month period. The majority (> 90%) of these specimens (n = 40) showed high iron content (up to 12 mg Fe/g tissue). The highest concentrations were associated with fibrosis and regenerative nodules. Dietary analysis indicated that the iron intake was not excessive, suggesting that iron-loading was due to enhanced intestinal absorption.  相似文献   
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Magnetic perovskite films have promising properties for use in energy-efficient spintronic devices and magnetic refrigeration. Here, an epitaxial ferromagnetic La0.67Ba0.33Mn0.95Ti0.05O3 (LBMTO-5) thin film was grown on SrTiO3(001) single crystal substrate by pulsed laser deposition. High-resolution X-ray diffraction proved the high crystallinity of the film with tetragonal symmetry. The magnetic, magnetocaloric and magnetoresistance properties at different directions of the applied magnetic field with respect to the ab plane of the film were investigated. An in-plane uni-axial magnetic anisotropy was evidenced. The LBMTO-5 epilayer exhibits a second-order ferromagnetic-paramagnetic phase transition around 234 K together with a metal–semiconductor transition close to this Curie temperature (TC). The magnetic entropy variation under 5 T induction of a magnetic field applied parallel to the film surface reaches a maximum of 17.27 mJ/cm3 K. The relative cooling power is 1400 mJ/cm3 K (53% of the reference value reported for bulk Gd) for the same applied magnetic field. Giant magnetoresistance of about 82% under 5 T is obtained at a temperature close to TC. Defined as the difference between specific resistivity obtained under 5 T with the current flowing along the magnetic easy axis and the magnetic field oriented transversally to the current, parallel and perpendicular to the sample plane, respectively, the in-plane magneto-resistance anisotropy in 5 T is about 9% near the TC.  相似文献   
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This assessment provides the most recent estimates of overweight and obesity among children 4 to 5 years old who were enrolled in public schools in the 2007–2008 school year, using data obtained from Student Health Records for 12,823 children, which represents 91% of the 14,070 children who were enrolled in kindergarten in 2007–2008. This assessment is a census of 4 to 5 year olds that entered public schools in Hawai‘i in 2007–2008 and represents approximately 38% of the total Hawai‘i population for those aged 4 to 5 years, since kindergarten is not a requirement. A limited data set with data on age, sex, height, and weight was used to calculate BMI (body mass index) percentiles. We compare this data with age and sex-specific BMI obtained from Student Health Records from 10,199 children aged 4 to 5 years entering public schools during 2002–2003. The results illustrate that like the 2002–2003 data (28.5%), over one in four (28.6%) of the children aged 4 to 5 years entering Hawai‘i public schools in 2007–2008 were either overweight or obese. Total proportions overweight and obese were persistently higher (32.5% or more in both 2002–2003 and 2007–2008) in some specific school complexes on O‘ahu as well as in some rural and Neighbor Island school complexes. Physicians, public health and school health professionals, advocates, schools, and communities should be vigilant about this persistent problem and seek to implement practices to combat overweight and obesity. In addition, the use of Student Health Records for on-going pediatric obesity surveillance should be explored more fully.  相似文献   
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BACKGROUND/AIMS: The recovery from iron overload is hampered by the limited number of pathways and therapeutic agents available for the augmentation of iron secretion/excretion. The present study was aimed to investigate the process of iron storage and release by cultured human hepatoma cells, the role of transferrin receptors and ferritin in this process as well as the effect of iron chelators. METHODS: We followed the acquisition, storage and release of iron by cultured cells HepG2 and Hep3B by biochemical means and electron microscopy. RESULTS: The uptake of iron from diferric transferrin (Trf) was extremely low, while iron as ferric-ammonium-citrate (FAC) was taken up readily, especially by Hep3B cells. Up to 80% of the iron taken up by hepatoma cells was released to the medium. The rate of spontaneous iron release depended on the extent of iron loading. ApoTrf and deferoxamine facilitated release after 1- and 7-day iron-exposure. Up to a third of the radio-iron released from the cells was associated with ferritin. The release of ferritin-iron was not enhanced by either deferoxamine or Trf. CONCLUSIONS: Ferritin-iron release appeared to be an important mechanism of iron discarding in cultured human hepatoma cells, independent of the activity of chelating agents.  相似文献   
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