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51.
Alok Thakar Chitra Sarkar Muthuswamy Dhiwakar Sudhir Bahadur Sonika Dahiya 《Otolaryngology--head and neck surgery》2004,130(2):209-216
OBJECTIVE: We sought to determine whether histologic tissue invasion occurs in allergic fungal sinusitis (AFS) and, if so, to identify clinical indicators for the same.Study design and setting We conducted a retrospective case record review of all 28 AFS cases identified by histology over a 32-month period at a tertiary care referral center. All histologic specimens were reevaluated for features of invasive pathology, and case records were correlated for clinical, radiologic, or laboratory parameters associated with such invasion. RESULTS: In addition to the universal finding of the characteristic allergic mucin with fungal elements on histopathologic examination of the sinus luminal contents, 6 cases (21%) had additional evidence of mucosal invasion as indicated by granulomatous inflammation and branching septate fungal hyphae in the submucosal tissues. Such coexistent invasion was associated with advanced disease as indicated by a higher incidence of orbital involvement on clinical evaluation (P = 0.024), and extrasinus spread (intraorbital or intracranial spread) on the computed tomography evaluation (P = 0.003). The single death that occurred on follow-up was in a patient with coexistent invasion. CONCLUSION: Advanced AFS may be complicated by histologic evidence of tissue invasion. SIGNIFICANCE: The noninvasive and invasive forms of fungal sinusitis are not necessarily discrete and may coexist in the same patient. Clinical features of orbital involvement or computed tomography manifestations of extrasinus spread should alert the clinician to the possibility of invasion. 相似文献
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A phospholipase A2 (EC 3.1.1.4) has been isolated and purified from the venom of Crotalus scutulatus salvini in 33% yield. The enzyme was homogeneous on polyacrylamide gel electrophoresis. The molecular weight of the enzyme was in the same range (30,000) whether determined by gel filtration or ultracentrifugation. On polyacrylamide gel electrophoresis, in the presence of sodium dodecyl sulphate and β-mercaptoethanol, the enzyme migrated into a single protein band with a mobility corresponding to about 14,000 molecular weight, indicating that the native enzyme was a dimer. Amino acid composition of the enzyme is reported. Two NH2-amino acid terminals were found which indicates that the dissociable monomers of the native enzyme were non-identical. Antiserum against the purified enzyme completely inhibited the phospholipase A2 activity and immunodiffusion of the antiserum against both purified phospholipase A2 and crude venom of Crotalus scutulatus salvini gave single precipitin lines indicating a lack of contaminating antigens. 相似文献
54.
Oken E Wright RO Kleinman KP Bellinger D Amarasiriwardena CJ Hu H Rich-Edwards JW Gillman MW 《Environmental health perspectives》2005,113(10):1376-1380
Fish and other seafood may contain organic mercury but also beneficial nutrients such as n-3 polyunsaturated fatty acids. We endeavored to study whether maternal fish consumption during pregnancy harms or benefits fetal brain development. We examined associations of maternal fish intake during pregnancy and maternal hair mercury at delivery with infant cognition among 135 mother-infant pairs in Project Viva, a prospective U.S. pregnancy and child cohort study. We assessed infant cognition by the percent novelty preference on visual recognition memory (VRM) testing at 6 months of age. Mothers consumed an average of 1.2 fish servings per week during the second trimester. Mean maternal hair mercury was 0.55 ppm, with 10% of samples > 1.2 ppm. Mean VRM score was 59.8 (range, 10.9-92.5). After adjusting for participant characteristics using linear regression, higher fish intake was associated with higher infant cognition. This association strengthened after adjustment for hair mercury level: For each additional weekly fish serving, offspring VRM score was 4.0 points higher [95% confidence interval (CI), 1.3 to 6.7]. However, an increase of 1 ppm in mercury was associated with a decrement in VRM score of 7.5 (95% CI, -13.7 to -1.2) points. VRM scores were highest among infants of women who consumed > 2 weekly fish servings but had mercury levels = 1.2 ppm. Higher fish consumption in pregnancy was associated with better infant cognition, but higher mercury levels were associated with lower cognition. Women should continue to eat fish during pregnancy but choose varieties with lower mercury contamination. 相似文献
55.
IL-6 induces regionally selective spinal cord injury in patients with the neuroinflammatory disorder transverse myelitis 总被引:3,自引:0,他引:3
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Kaplin AI Deshpande DM Scott E Krishnan C Carmen JS Shats I Martinez T Drummond J Dike S Pletnikov M Keswani SC Moran TH Pardo CA Calabresi PA Kerr DA 《The Journal of clinical investigation》2005,115(10):2731-2741
Transverse myelitis (TM) is an immune-mediated spinal cord disorder associated with inflammation, demyelination, and axonal damage. We investigated the soluble immune derangements present in TM patients and found that IL-6 levels were selectively and dramatically elevated in the cerebrospinal fluid and directly correlated with markers of tissue injury and sustained clinical disability. IL-6 was necessary and sufficient to mediate cellular injury in spinal cord organotypic tissue culture sections through activation of the JAK/STAT pathway, resulting in increased activity of iNOS and poly(ADP-ribose) polymerase (PARP). Rats intrathecally infused with IL-6 developed progressive weakness and spinal cord inflammation, demyelination, and axonal damage, which were blocked by PARP inhibition. Addition of IL-6 to brain organotypic cultures or into the cerebral ventricles of adult rats did not activate the JAK/STAT pathway, which is potentially due to increased expression of soluble IL-6 receptor in the brain relative to the spinal cord that may antagonize IL-6 signaling in this context. The spatially distinct responses to IL-6 may underlie regional vulnerability of different parts of the CNS to inflammatory injury. The elucidation of this pathway identifies specific therapeutic targets in the management of CNS autoimmune conditions. 相似文献
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Cerebral palsy is a common neurodevelopmental condition encountered by pediatricians. The condition may present itself in
many diferent clinical spectra. The etiological and risk factors are many and an awareness of the interplay of multiple factors
in the causation of CP is crucial. In many cases, the cause of Cerebral palsy may not be apparent. Cerebral palsy is invariably
associated with many deficits such as mental retardation, speech and language and oromotor problems. A thorough neurodevelopmental
assessment of the child with Cerebral Palsy should include evaluation of associated deficits so that a comprehensive early
intervention program an be planned and executed. 相似文献
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Amplatzer Angled Duct Occluder for Closure of Patent Ductus Arteriosus Larger than the Aorta in an Infant 总被引:3,自引:0,他引:3
Transcatheter closure of patent ductus arteriosus (PDA) by Amplatzer duct occluder is the treatment of choice. However, closure
of very large ducts in infants with low weight is a challenge for the interventionalist because a large device may obstruct
the aorta or left pulmonary artery. Difficulty is also encountered in advancing the device around the curve of the right ventricular
outflow tract toward the pulmonary artery; this curve is tight, more or less at a right angle in infants, leading to kinking
of the sheath, which increases fluoroscopic time. This is the first reported case of a very large PDA (8.7 mm), larger than
the aorta (8.2 mm), successfully closed by an Amplatzer angled duct occluder in an infant weighing 5 kg. 相似文献
60.