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51.
Undifferentiated nasopharyngeal carcinoma is associated with Epstein-Barr virus (EBV) infection. Presence of EBV IgA antibodies is rare among healthy individuals and is used as a marker of nasopharyngeal carcinoma in high-incidence populations. Reasons for EBV IgA seropositivity are unknown, but high EBV IgA levels have been found among unaffected close family members and spouses to nasopharyngeal carcinoma patients in Chinese populations. In Greenland, a nasopharyngeal carcinoma-high-incidence area, we compared EBV serology and viral load in high-risk nasopharyngeal carcinoma family members (N = 20) and controls without nasopharyngeal carcinoma-affected relatives (N = 90). There was no significant difference in EBV viral loads between relatives and controls, and EBV was detected in plasma in 5.0% of relatives and 11.4% of controls. There was no significant difference in EBV serology, but the seroprevalence of EBV viral capsid antigen (VCA) IgA was high in both relatives (25.0%) and controls (20.5%). Compared with anti-VCA IgA-negative, anti-VCA IgA-positive individuals had significantly higher EBV viral loads in peripheral blood mononuclear cells (PBMCs) (P < 0.01). The very high prevalence of anti-VCA IgA indicates that this antibody is unsuitable for nasopharyngeal carcinoma screening among Inuits.  相似文献   
52.
Background and aimsBody mass index (BMI) and waist circumference (WC) are commonly used markers of cardiometabolic risk. However, sagittal abdominal diameter (SAD) has been proposed as a possibly more sensitive marker of intra-abdominal obesity. We investigated differences in how SAD, WC, and BMI were correlated with cardiometabolic risk markers.Methods and resultsThis cross-sectional study investigated anthropometric and metabolic baseline measurements of individuals from six trials. Multiple linear regression and (partial) correlation coefficients were used to investigate associations between SAD, WC, and BMI and cardiometabolic risk markers, including components of the metabolic syndrome as well as insulin resistance, blood lipids, and lowgrade inflammation.In total 1516 mostly overweight or obese individuals were included in the study. SAD was significantly more correlated with TG than WC for all studies, and overall increase in correlation was 0.05 (95% CI (0.02; 0.08). SAD was significantly more correlated with the markers TG and DBP 0.11 (95% CI (0.08, 0.14)) and 0.04 (95% CI (0.006, 0.07), respectively compared to BMI across all or most studies.ConclusionThis study showed that no single anthropometric indicator was consistently more strongly correlated across all markers of cardiometabolic risk. However, SAD was significantly more strongly correlated with TG than WC and significantly more strongly correlated with DBP and TG than BMI.  相似文献   
53.
54.
In the beginning of this century, a Danish dermatologist, Professor Niels Finsen, received the Nobel Prize for his showing of the beneficial effects of UV-light on certain skin diseases. We have subsequently learned that UV-light is far from being only beneficial to our health. UV-light is an important risk factor for malignant melanoma and squamous cell carcinoma of the skin (1). Furthermore, UV-light appears to have immunosuppressive effects, not only on the local skin, but on the immune system in general (2-4). Recently, it was suggested that UV-light may also increase the risk of non-Hodgkin's lymphoma (NHL) (5, 6).  相似文献   
55.
Acute respiratory infections (ARI) are frequent in Inuit children, in terms of incidence and severity. A cohort of 294 children <2 years of age was formed in Sisimiut, a community on the west coast of Greenland, and followed from 1996 to 1998. Data on ARI were collected during weekly visits at home and child-care centers; visits to the community health center were also recorded. The cohort had respiratory symptoms on 41.6% and fever on 4.9% of surveyed days. The incidence of upper and lower respiratory tract infections was 1.6 episodes and 0.9 episodes per 100 days at risk, respectively. Up to 65% of the episodes of ARI caused activity restriction; 40% led to contact with the health center. Compared with studies from other parts of the world, the incidence of ARI appears to be high in Inuit children.  相似文献   
56.
The aims of the study were to study chronic pain in land mine accident survivors, and to study the impact of trauma and trauma care parameters on chronic pain. The level of chronic pain was registered (patient-rated and by clinical examination) in 57 severely injured adult land mine accident survivors in Cambodia and Northern Iraq more than one year after the accident. As all study patients had been managed by a standardized trauma system, we could assess the impact of injury severity and primary trauma care on chronic pain. 64% of the study patients (n=36) had chronic pain syndromes (non-significant difference between the two countries). 68% of the amputees (19 out of 28) had phantom limb pain. Pre-injury trauma exposure, the severity of the actual trauma, and the quality of trauma care had no impact on end point chronic pain. In 85% of cases (n=48), the economic standing of the patients' family had deteriorated after the accident. Patient-rated loss of income correlated with the rate of chronic pain syndromes.  相似文献   
57.
Objective: The increased risk of breast cancer in women with family history of breast cancer (FHBC) might be reduced by early childbirths. However, childbirth induces a transient increase in risk in the first 5–10 years, which coincides with the relatively increased risk of family cases at a young age. The objective was to investigate this short-term change in risk according to FHBC. Methods: We used a population-based cohort of 1.5 million Danish women. Between 1968 and 1990, 2770 incident cases of breast cancer below 40 years of age were identified in the Danish Cancer Register, of whom 276 (10%) had a FHBC. Results: The first 5 years after a birth the short-term increase in risk was 30% (3–64%) larger in women with FHBC than without FHBC. After the first 5 years we observed no difference in the effect of a birth between women with and without FHBC. Conclusions: The adverse short-term effect of childbirth is stronger in women with FHBC.  相似文献   
58.
HYPOTHESIS: Tympanometric measurements of middle ear pressure in children with secretory otitis media are overestimated in a dose-response manner because of increased hysteresis explained by the viscosity and amount of middle ear fluid. BACKGROUND: Tympanometric middle ear pressure is important in evaluating children with secretory otitis media. These measurements are influenced by hysteresis appearing as a peak pressure difference in bidirectional tympanometry. This represents an inaccuracy of 0.5 x peak pressure difference, which is only 5 to 25 daPa in normal ears. However, previous experiments found increased hysteresis, suggesting an inaccuracy of 225 daPa in secretory otitis media ears. MATERIALS AND METHODS: In 56 patients with secretory otitis media, bidirectional tympanometry was performed; Type B curves were excluded. The middle ear fluid was semiquantified subsequently at surgery according to viscosity (serous, seromucoid, or mucoid) and amount (small, medium, or large). A control group included 28 normal children. Peak pressure difference was calculated by the difference between middle ear pressure determined by a positive and negative pressure sweep. RESULTS: Mean peak pressure difference was 10 and 69 daPa in the normal and secretory otitis media groups, respectively (p <0.001). However, peak pressure difference ranged to 205 daPa in the secretory otitis media group and showed a significant positive correlation to viscosity and amount of the fluid (both p <0.0001). CONCLUSION: Peak pressure difference is significantly increased in secretory otitis media because of additional damping explained by the viscosity and amount of the fluid. The mean error was 5 daPa in normal ears and 35 daPa in secretory otitis media ears, but ranged to greater than 100 daPa. These results were only a low estimate of the inaccuracy, because patients with Type B tympanograms could not be included, and errors of more than 100 daPa can be anticipated.  相似文献   
59.
HYPOTHESIS: Pathologic changes around the vein of the vestibular aqueduct (VVA) may cause obstruction to the flow of blood toward the sigmoid sinus. Furthermore, a distal obstruction of this vessel may be responsible for a development of a retrograde flow of blood with concomitant drainage of endolymphatic sac (ES) substances to the inner ear. BACKGROUND: The VVA is responsible for the venous drainage of the vestibular apparatus and endolymphatic duct and ES. Previous studies have linked the VVA to Ménière's disease. The aim of the present article was a 3-dimensional perspective study of the VVA with its adjacent anatomic structures. METHODS: In 14 rats, the VVA was examined by 3-dimensional reconstruction of 2-microm serial sections, corrosion cast technique, and scanning electron microscopy. RESULTS: From the external aperture of the vestibular aqueduct, the VVA is interposed between the ES and the operculum. Three to 4 collecting venules from the ES drain into the VVA. The VVA merges at an oblique angle with the sigmoid sinus. CONCLUSION: The VVA courses near the ES, operculum, and sigmoid sinus and is potentially vulnerable to expanding structures in the cranial posterior fossa. The possible role of the VVA for the function of the ES under normal and pathologic conditions is discussed.  相似文献   
60.
Friborg J  Wohlfahrt J  Melbye M 《Cancer》2005,103(1):211; author reply 211-211; author reply 212
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