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Immunologic Research - Cystic echinococcosis (CE) is a neglected helminthic zoonosis caused by the larval stage of the tapeworm Echinococcus granulosus s.l. MicroRNAs (miRNAs) are regulators of...  相似文献   
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OBJECTIVES: The purpose of this study was to simultaneously determine the impact of exposure times and incremental resin composite overlaying thickness on the cure kinetics of a light activated composite and a dentin adhesive at selected depths of a simulated restoration. METHODS: Levels and kinetics of polymerization of a light activated resin composite (Z250, 3M-ESPE) and dentin adhesive (Excite, Ivoclar) cured with a halogen light unit (Demetron, Kerr, USA) operating at low/medium intensity (500 mW/cm2) for different exposure durations (20 and 60 s) were measured at selected depths (0.3, 0.6 and 1mm) using a modified calorimetric analyzer (DSC 25, METLLER-TOLEDO). RESULTS: Final polymerization levels of materials up to 1mm through the composite are not significantly different while the light shielding effect of incremental resin composite overlaying progressively reduces their reaction rates. SIGNIFICANCE: Prolonged irradiation time at low/medium energies is effective for proper conversion of a resin composite and dentin adhesive; 60 s irradiation time provides the maximum obtainable conversion through the dental resin composite for thicknesses up to 1mm.  相似文献   
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Myocardial infarction (MI) occurs more frequently in the morning as a result of the concomitant unfavorable timing of several physiological parameters and/or biochemical conditions. However, little is known about the possible influence of this circadian pattern on prognosis. To evaluate whether the time of symptom onset could potentially influence mortality from acute MI, this prospective study considered all consecutive MIs admitted to the ED of Ferrara, Italy, after a call to the Emergency Coordinating Unit from January 1, 1998, to December 31, 2001. The total sample consisted of 442 MIs (mean age, 68.7 years; males, 72%). Eighty patients (males, 82.5%) died in the ED; the remaining 362 were admitted to the hospital. Of these, 50 (males, 60%) died during their hospital stay. Based on the timing of their symptom onset, cases were categorized both into 24 1-hour intervals and four 6-hour intervals (midnight to 5:59 am, 6:00 am to 11:59 am, noon to 5:59 pm, and 6:00 pm to 11:59 pm), and the circadian distributions of fatal versus nonfatal MIs were compared. The circadian variation of MI peaked between 6:00 am and noon (P < .001), and in this period, there was a trend toward a higher frequency of fatal cases (41.5% vs. 35.2%; chi(2) = 1.911, P = .167). To verify whether this higher frequency of fatal events in the morning hours could be related to possible higher severity of cases observed in that hours, a further separate analysis considering age, infarct site, and peak levels of MB was made. Again, no significant temporal differences among the four 6-hour intervals were found between fatal and nonfatal Mis, although a trend toward older age was observed in morning MIs. Not only the frequency, but also the mortality, of acute MI could be increased in the morning hours. This could be of practical interest for emergency doctors and could have significant implications for acute treatment, because several studies have reported a lowered efficacy of thrombolytic drugs in the morning hours.  相似文献   
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Paragangliomas (PGs) of the head and neck region are typically benign, slow-growing neuroendocrine tumours. At times, they may exhibit unusual histological features, such as prominent stromal sclerosis (sclerosing PG), which may raise concerns of malignancy. We describe a case of sclerosing PG of the carotid body, emphasizing the value of immunohistochemical stains for differential diagnosis. A 43-year-old woman presented with a painless lump on the neck. A magnetic resonance imaging scan demonstrated a hypervascular lesion of the carotid body, which was surgically excised. Grossly, the lesion measured 1.8 cm at maximum diameter. On microscopic examination, irregular nests and tiny bundles of neoplastic cells were found between thick bands of fibrous tissue. Focal nuclear cytomegaly and marked pleomorphism were noted. Neoplastic cells proved to be immunoreactive for chromogranin, synaptophysin and neuron specific enolase, but negative for cytokeratins, smooth muscle actin and CD34. Ultrastructurally, numerous mitochondria, rough endoplasmic reticulum structures and endocrine granules were seen in the cytoplasm of the tumour cells. On consideration of the above-mentioned clinico-pathological and ultrastructural findings a diagnosis of sclerosing PG was established. Sclerosing PG is a rare entity which may mimic a malignant neoplasm. The recognition of this unusual morphological variant of PG, together with appropriate immunostains, leads to the correct diagnosis.  相似文献   
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Bronchiolitis is the first lower respiratory tract viral infection manifesting in infants younger than 12 months of age. Our aim was to evaluate clinical and serological differences in infants with bronchiolitis from a single or from multiple viruses. Our secondary aim was to investigate differences in recurrent wheezing episodes after 12‐24‐36 months of follow‐up. We reviewed the clinical records for 486 full‐term infants hospitalized for bronchiolitis with at least one virus detected in the nasopharyngeal aspirate. In 431 (88.7%) patients one virus was detected and in 55 (11.3%) infants more than one virus was found. No differences were observed in the length of hospitalization, clinical severity score, O2 supplementation or admission to the intensive care unit. Single virus was associated with higher serum C‐reactive protein (C‐RP) than infants with multiple viruses and higher blood neutrophil counts. Respiratory syncytial virus (RSV) was the most frequently detected virus. RSV alone was associated with higher C‐RP (P = 0.007), compared to RSV coinfection. Infants with human rhinovirus (hRV) alone had higher white blood cell counts, higher blood neutrophils, and higher serum C‐RP levels than hRV co‐infection (P = 0.029, P = 0.008, P = 0.008). RSV + hRV, the most frequent co‐infection, was associated with lower neutrophil count and lower C‐RP levels (P = 0.008, P = 0.016) and less fever (P = 0.012), when comparing RSV versus hRV versus RSV + hRV. No differences were found in the frequency of recurrent wheezing between single versus multiple viruses after bronchiolitis. Our findings suggest that in infants with bronchiolitis multiple viral co‐infections can occur, without influence in the clinical severity of the disease. Infants with co‐infection seems to mount a lower inflammatory response.
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