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21.
Sj?gren-Larsson syndrome: inherited defect in the fatty alcohol cycle   总被引:5,自引:0,他引:5  
We investigated fatty alcohol metabolism in eight patients with Sj?gren-Larsson syndrome, and in nine obligate heterozygotes. Fatty alcohol: nicotinamide-adenine dinucleotide oxidoreductase (FAO) activity was deficient in cultured skin fibroblasts (mean 18% of normal, n = 8) and peripheral blood leukocytes (mean 22% of normal, n = 3) from patients with Sj?gren-Larsson syndrome. The palmitoyl coenzyme A-inhibitable component of FAO activity was decreased to 10% and 15% of normal in fibroblasts and leukocytes, respectively, of patients with Sj?gren-Larsson syndrome. Most affected patients accumulated long-chain fatty alcohol in plasma, with a greater relative accumulation of octadecanol (mean threefold greater than normal) than hexadecanol (mean twofold greater than normal). Erythrocyte lipid alkyl ether linkages derived from hexadecanol were slightly increased in three of four patients. Fibroblasts and leukocytes from heterozygotes with Sj?gren-Larsson syndrome showed mean FAO activities that were intermediate between those seen in homozygotes and in normal control subjects. The heterozygotes had normal fatty alcohol concentrations in plasma. These studies demonstrate FAO deficiency in patients with Sj?gren-Larsson syndrome, and suggest that accumulation of fatty alcohol or its metabolic products may be important in the pathogenesis of this disorder.  相似文献   
22.
Summary Total saliva and secretions from parotid and submandibular glands of patients with carcinomas in the oral cavity, oropharynx or larynx and a control group of healthy individuals were analyzed for concentrations of glycosidically bound sugars and free N-acetylneuraminic acid as well as for sialidase activity. When compared to the data obtained for normal donors, the relative amounts of the individual monosaccharides fucose, galactose, mannose, N-acetylgalactosamine, and N-acetylglucosamine as components of glycoconjugates showed variable differences to the group of tumor patients depending on the type of secretion and the location of the tumor. The percentage of glycosidically linked N-acetylneuraminic acid, however, was always higher for the healthy donors. A significant difference was found in the amount of free sialic acid, with the exception of submandibular gland secretion from a patient with an oropharyngeal carcinoma, and sialidase activity which were increased for tumor patients, independent of the type of secretion and the location of the tumor. From these results it is concluded that free sialic acid and sialidase activity may be considered as markers for carcinomas in the upper aerodigestive tract.  相似文献   
23.
Koitschev A  Baumann I  Remy CT  Dammann F 《HNO》2002,50(3):217-222
Movement or metal artefacts as well as the relatively high radiation exposure of both the axial and the coronal scan are disadvantages of computed tomography. A single spiral CT scan with a secondary reformation replacing the second CT scan might solve these problems. The goal of this project was to compare the diagnostic value of primary spiral CT scans of paranasal sinuses with secondary reformations. These were evaluated by ENT surgeons as well as radiologists. We performed axial and coronal spiral-CT's of paranasal sinuses in 80 patients. The secondary coronal and axial reformations were calculated with 2 mm image sections. Although a reduced resolution was observed in the secondary reformations, this did not compromise the detection of important anatomical features. Image deterioration due to artifacts was significantly reduced.  相似文献   
24.
To test the hypothesis that characteristics of perinatal infection are associated with long-term cognitive limitations among preterm infants, we analyzed data from 294 infants (142 females, 152 males) < or = 1500 g birthweight and <37 completed weeks of gestation who were examined at age 9 years. We identified 47 children (20 females, 27 males) who had a non-verbal Kaufman Assessment Battery for Children (K-ABC) scale standard value below 70, i.e. more than 2 SDs below the age-adjusted mean. The 247 children (122 females, 125 males) with a score > or = 70 served as control participants. Maternal nationality and education, and low gestational age were significantly associated with a K-ABC non-verbal standard value <70. Both neonatal brain damage (intraventricular hemorrhage) and long-term sequelae (cerebral palsy [CP], diagnosed at age 6 years) were significantly associated with a below-normal non-verbal K-ABC score. Maternal fever at birth was present in five cases (11%) and eight controls (3%; odds ratio 3.6, 95% confidence interval 1.1 to 11.4). Clinical chorioamnionitis and preterm labor and/or premature rupture of membranes (as opposed to toxemia and other initiators of preterm delivery) were also more common among cases than control participants. When adjusting for potential confounders such as gestational age, maternal education and nationality, and CP, the risk estimate for maternal fever remained unchanged (3.8, 0.97 to 14.6). We conclude that perinatal infection might indeed contribute to an increased risk for long-term cognitive deficits in preterm infants.  相似文献   
25.
Increasing evidence supports the view that infants exposed to perinatal infection are at increased risk for brain injury. We suggest that elevated cytokines in the amniotic fluid or in the fetal circulation be viewed as a humoral expression and that inflammatory cells in chorionic plate or umbilical cord blood vessel walls be viewed as a morphologic expression of the fetal inflammatory response. We discuss the evidence supporting the hypothesis that the fetal inflammatory response contributes to neonatal brain injury and later developmental disability. Little support has been found for a maternal contribution. Intervention should be designed with the fetus in mind.  相似文献   
26.
Aim: Gender differences in morbidity have been widely confirmed in representative health surveys in North America and Europe. Significantly more women than men suffer from somatic complaints. It is less clear whether differences in symptom reporting provide an impact on health care utilization and to which degree psychosocial factors exhibit confounding influence. Methods: We analyzed data from a representative health examination survey in Germany with 7466 participants in the age range of 25 to 69 years. Results: The analysis confirmed an overall excess in female symptom reporting, both in the total sample (n = 7460; p 0.001) and in the healthy subsample (n = 906, p 0.01). Also, female utilization of medical services was higher (p 0.0001). A simultaneous age related increase in the prevalence of symptom reporting in both groups peaked in the age group of 55–59 years followed by a subsequent slight decrease in higher age groups whereas utilization steadily increased over the adult life span in both sexes. As expected, more medical utilization was associated with higher symptom reporting levels. Nevertheless, females constantly exhibited more medical utilization than males in all symptom reporting groups. Age and marital status had no univariate influence on symptom reporting whereas low social class status (p = 0.001), poor perceived/self assessed health (p < 0.0001), and high levels of chronic distress (p < 0.0001) were associated with more symptom reporting. In multivariate analysis, the female gender lost its significance on heightened symptom reporting. Poor perceived/self assessed health had the most pronounced impact on symptom count (F-value 59.1; p < 0.001). Conclusions: The present study confirms a female excess of symptom reporting and utilization of medical services. Nevertheless, symptom reporting and utilization are not closely related. The gender gap in symptom reporting may be largely explained by low social class status, high levels of chronic distress and poor perceived/self assessed health.  相似文献   
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