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81.
We previously reported that mice subjected to partial hepatectomy exhibit rapid development of hypoglycemia followed by transient accumulation of fat in the early regenerating liver. We also showed that disrupting these metabolic alterations results in impaired liver regeneration. The studies reported here were undertaken to further characterize and investigate the functional importance of changes in systemic adipose metabolism during normal liver regeneration. The results showed that a systemic catabolic response is induced in each of two distinct, commonly used experimental models of liver regeneration (partial hepatectomy and carbon tetrachloride treatment), and that this response occurs in proportion to the degree of induced hepatic insufficiency. Together, these observations suggest that catabolism of systemic adipose stores may be essential for normal liver regeneration. To test this possibility, we investigated the hepatic regenerative response in fatty liver dystrophy (fld) mice, which exhibit partial lipodystrophy and have diminished peripheral adipose stores. The results showed that the development of hypoglycemia and hepatic accumulation of fat was attenuated and liver regeneration was impaired following partial hepatectomy in these animals. The fld mice also exhibited increased hepatic p21 expression and diminished plasma levels of the adipose-derived hormones adiponectin and leptin, which have each been implicated as regulators of liver regeneration. Conclusion: These data suggest that the hypoglycemia that develops after partial hepatectomy induces systemic lipolysis followed by accumulation of fat derived from peripheral stores in the early regenerating liver, and that these events may be essential for initiation of normal liver regeneration.  相似文献   
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Abstract   Vertebral artery injuries can be seen following trauma. Most traumatic vertebral artery injuries are limited to an intimal dissection. Rarely, transection of the vertebral artery can be seen with extravasation of hemorrhage into the surrounding soft tissues of the neck. Dural tears are rare in the setting of trauma. They are usually the result of penetrating trauma or severe blunt trauma. We present a case with both a vertebral artery transection and a dural tear. The combination of these lethal injuries resulted in extravasation of hemorrhage into the soft tissues of the neck, through the dural tear, and into the subarachnoid space of the cervical spine. The subarachnoid hemorrhage extended superiorly into the brain. The diagnosis was made by computed tomography (CT) and computed tomography angiography (CTA). The treatment of traumatic vertebral artery transections and dural tears are discussed.  相似文献   
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Opinion statement Primary cardiac tumors are rare in pediatrics. Their clinical presentation differs among the various age groups (fetus to the young adult). Our discussion focuses on the diagnosis and treatment of rhabdomyomas, fibromas, myxomas, and pericardial teratomas in the fetus and neonatal stages. Fetal diagnosis has been described in association with rhabdomyomas, fibromas, and pericardial teratomas. It is made by echocardiography prompted by fetal dysrhythmias, nonimmune hydrops, intrauterine growth restriction, and familial tuberous sclerosis. Based on our experience, it is of the utmost importance to refer these patients to a tertiary center for detailed evaluation, follow-up, and delivery. Tumor diagnosis in the neonatal age group may be prompted by a murmur, dysrhythmia, conduction block, and hemodynamic compromise or hypoxemia due to right or left inflow or outflow tract obstruction. Prenatal diagnosis of a hemodynamically significant mass mandates the presence of a neonatal intensivist in the delivery room for prompt initiation of advanced life support (intubation, mechanical ventilation, and central venous access), and early initiation of prostaglandin E1 to establish ductus arteriosus patency. Severe inflow obstruction associated with a restrictive atrial septum may require balloon atrial septostomy. Emergent transvenous pacing is indicated in the face of high-degree atrioventricular block. Early surgical removal of the mass after initial stabilization in the neonatal or cardiac intensive care unit may be indicated.  相似文献   
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OBJECTIVE: We describe a case of sex reassignment surgery and the subsequent development of lupus erythematosus tumidus (LET). LET is characterized clinically by erythematous, succulent, edematous, nonscarring plaques in sun-exposed areas. Results of histological examination show perivascular and periadnexal lymphocytic infiltration and interstitial mucin deposition. This report emphasizes that environmental triggers, including prolonged exposure to significant doses of estrogens as part of sex reassignment surgery, may lead to the development of lupus in a nonpredisposed individual.  相似文献   
86.
Recently we described iodinated homopolymeric radiopaque nanoparticles of 28.9 ± 6.3 nm dry diameter synthesized by emulsion polymerization of 2-methacryloyloxyethyl(2,3,5-triiodobenzoate) (MAOETIB). The nanoparticle aqueous dispersion, however, was not stable and tended to agglomerate, particularly at weight concentration of dispersed nanoparticles above 0.3%. The agglomeration rate increases as the concentration of nanoparticles in aqueous phase rises and prevents the potential in vivo use as contrast agent for medical X-ray imaging. Here we describe efforts to overcome this limitation by synthesis of iodinated copolymeric nanoparticles of 25.5 ± 4.2 nm dry diameter, by emulsion copolymerization of the monomer, MAOETIB, with a low concentration of glycidyl methacrylate (GMA). The surface of resulting copolymeric nanoparticles is far more hydrophilic than that of polyMAOETIB (PMAOETIB) nanoparticles. Therefore, P(MAOETIB-GMA) nanoparticles are significantly more stable against agglomeration in aqueous continuous phase. After intravenous injection of P(MAOETIB-GMA) nanoparticles in rats and mice (including those with a liver cancer model) CT-imaging revealed a significant enhanced visibility of the blood pool for 30 min after injection. Later, lymph nodes, liver and spleen strongly enhanced due to nanoparticle uptake by the reticuloendothelial system. This favorably enabled the differentiation of cancerous from healthy liver tissue and suggests our particles for tumor imaging in liver and lymph nodes.  相似文献   
87.
During the 11-year period from 1997 to 2007, 321 isolates of Listeria monocytogenes from sporadic cases of invasive listeriosis were reported to the national reference laboratory in Israel. Of these isolates, 113 (35%) were identified from perinatal cases, and 208 (65%) from non-perinatal cases. The prevalent serovars were 4b, 1/2b, 1/2a and 4c. Serovar 4b was identified in 80.5% of the perinatal isolates (P=0.0162), while the number of 1/2b and 1/2a strains increased in the > or = 60 years old group (P=0.0285). Resistance to tetracycline was found in eight 4b isolates. The seasonal distribution showed that 206 isolates (64.2%) were submitted during the hot season (May-October). The estimated morbidity for the study period was 4.4 per million. The incidence of invasive listeriosis was higher in the perinatal group (5.6/100 000), than in individuals aged > or = 60 years (1.5/100 000).  相似文献   
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