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A second pregnancy of young, nonconsanguineous parents of Macedonian ethnic origin was examined by ultrasound. Polyhydramnios and hydrops fetalis were found as well as severe short limb, short stature, and cystic hygroma of the neck. An artificial abortion was performed at the age of 23 weeks. The radiological features included moth‐eaten severely shortened long bones and ectopic calcifications of long bones, vertebral column, ribs, pelvis, larynx, trachea. In addition, the fetus had large head with depressed nasal bridge, severe platyspondyly, and short barrel‐shaped trunk. Light microscopy demonstrated lack of chondrocyte columns and disorganization of the cartilaginous architecture. This is the seventh reported case of this rare form of lethal skeletal dysplasia. © 2002 Wiley‐Liss, Inc.  相似文献   
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RHAMM (Receptor for Hyaluronic Acid Mediated Motility) has been identified as a receptor for the extracellular matrix component hyaluronan (HA) and was recently shown to be essential for the locomotion of normal and transformed peripheral cells. Until now the potential role of RHAMM in the motility of neural-derived cells has not been investigated. Here, we report that cultured primary astrocytes, astrocyte cell lines, and microglia express this receptor and exhibit RHAMM-dependent motility. Immunocytochemical localization of RHAMM showed that it was often present as aggregates at the periphery of cells in contact with one another or concentrated on protruding processes of isolated cells. Glial cells contained 50 and 72 kDa forms of RHAMM, and both of these forms were found to have HA binding capacity. Time lapse imaging of cell locomotion revealed a significant inhibition of motility and process elongation by neutralizing anti-RHAMM antibodies and by peptides corresponding to the HA binding domains of RHAMM. These results demonstrate that RHAMM serves a role in glial cell locomotion in vitro and provide the basis for investigations of the motile behavior of glial cells in vivo after CNS injury.  相似文献   
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Cyclosporine (CsA), commercially available as iv or oral Sandimmune, is a potent immunosuppressant which can induce dose-related nephrotoxocity. In addition, the iv product contains a solubilizing agent, Cremophore EL, which in itself is reported to be nephrotoxic and can induce, in sensitized patients, anaphylactic reactions. Solubilization of CsA with liposomes or lipid emulsions could provide a suitable alternative dosage form for iv administration. With this in mind, male New Zealand white rabbits were given iv CsA (10 mg/kg) in three different dosage forms: (1) CsA:liposomes; (2) CsA:Intralipid (soybean oil and phospholipids); and (3) the commercially available Sandimmune (cyclosporine). The CsA concentration in whole blood samples was analyzed by HPLC. The terminal disposition half-life of CsA (t1/2 beta) ranged from 400 to 475 min and was not statistically different among the three groups. However, the distribution characteristics of CsA changed dramatically depending on the dosage form. The volume of distribution of CsA at steady state (Vdss) in Sandimmune was 2.7 +/- 0.2 L/kg and was significantly lower than that of either Intralipid (10.6 +/- 2.7 L/kg) or liposomes (7.4 +/- 2.3 L/kg). A significantly lower total body clearance (TBC) of CsA also was seen for Sandimmune (12.7 +/- 0.3 mL/min/kg) as compared with that of either Intralipid (24.4 +/- 8.2 mL/min/kg) or liposomes (18.9 +/- 3.9 mL/min/kg). Since CsA is extensively bound to lipoproteins, it is surprising that both test vehicles showed a different distribution pattern.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Migraine is a common, disabling disorder associated with considerable personal and societal burden. Current guidelines recommend triptans for the acute treatment of migraine unlikely to respond to less effective therapies. Rizatriptan is a second-generation triptan available in tablet or orally disintegrating tablet (wafer) formulations that offers several advantages over other members of its class. Rizatriptan is rapidly absorbed from the gastrointestinal tract and achieves maximum plasma concentrations more quickly than other triptans, providing rapid pain relief. Clinical trials have shown that rizatriptan is at least as effective or superior to other oral migraine-specific agents in the acute treatment of migraine, and has more consistent long-term efficacy across multiple migraine attacks. Rizatriptan has a favorable tolerability profile, and patients have reported greater satisfaction and a preference for rizatriptan over other migraine-specific agents. Improvements in quality of life reported with rizatriptan are consistent with its favorable efficacy and tolerability profiles. Notably, multi-attribute decision models that combine clinical data with patient- and physician-reported treatment preferences have identified rizatriptan as one of three triptans closest to a hypothetical “ideal”. The efficacy and tolerability of rizatriptan for the acute treatment of migraine have thus been well established.  相似文献   
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A pseudotumor, giant regenerative nodule, or macroregenerative nodule is an unusual benign hepatic lesion in biliary atresia (BA) patients. This tumor may mimic malignant transformation and may preclude liver transplantation (LT). The clinical and imaging surveillance of patients after the Kasai procedure is therefore an important aspect of management of BA patients. Our objective is to report our experience and describe the incidence, imaging, and pathologic features of pseudotumors in BA patients awaiting LT. From August 1990 to December 2006, 133 LTs for BA were performed. Five (3.8%; 4 female, 1 male) patients were diagnosed with pseudotumor. The patients' records were reviewed. The diagnostic imaging modalities used were abdominal ultrasound (US), computed tomography (CT) scan, and magnetic resonance imaging (MRI). Histologic confirmation of the lesions was obtained in all cases. All underwent the Kasai operation in early infancy. Six of 7 lesions in 4 of 5 patients were demonstrated by pretransplant imaging. Two of 7 tumors were detected by US. Five of 7 lesions were detected by CT, and 5 of 7 lesions were demonstrated by MRI. In 1 patient, the lesion was not seen in the US, CT, or MRI but was found during surgery and confirmed by histology. An additional tumor was found incidentally during histologic examination in a patient previously diagnosed to have 2 tumors by CT and MRI. In another patient diagnosed to have 2 tumors on imaging, pathology revealed only a single tumor. In conclusion, although unusual, pseudotumor should be included in the differential diagnosis of liver masses in BA children.  相似文献   
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