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BACKGROUND: Two mutations in a newly described gene, HFE, have been proposed as genetic markers for the inherited iron overload disease, genetic haemochromatosis. METHODS: We assessed the frequency of both mutations in a cohort of genetic haemochromatosis patients and compared these with a control population. The patients were genetic haemochromatosis patients from Western Australia whose diagnosis met strict criteria for phenotypic expression. Control patients had other liver disease where iron overload was excluded. RESULTS: Genomic DNA of 72 genetic haemochromatosis patients and 69 controls was examined for the C282Y and H63D mutations of the HFE gene using polymerase chain reaction amplification and restriction enzyme digestion. In genetic haemochromatosis patients, the C282Y mutation was homozygous in 64 of 72, giving a sensitivity of 89% (95% confidence interval 82-96%), heterozygous in five (7%) and absent in another three (4%), whereas none of the control subjects were homozygous. The H63D mutation was present in one genetic haemochromatosis patient and was not useful as a diagnostic marker. In this cohort of Western Australian patients with phenotypic expression of genetic haemochromatosis, the specificity of a homozygous C282Y mutation for genetic haemochromatosis was 100%. CONCLUSIONS: The results indicate that genotyping for the C282Y mutation is a useful test for the diagnosis of genetic haemochromatosis in clinical practice.  相似文献   
995.
STUDY OBJECTIVE: The most common extraintestinal manifestation of Entamoeba histolytica, the agent of amebiasis, is a hepatic abscess. This infection is common throughout the world and can be associated with life-threatening consequences. Given the often nonspecific nature of the complaints related to an amebic abscess, a retrospective review of patients with confirmed disease was done to recognize the most common patterns of presentation. METHODS: A retrospective case series was conducted of all patients with confirmed amebic liver abscess over a 5-year period. All available emergency department and inpatient records were reviewed. Age, sex, country of origin, chief complaint (including duration), vital signs, and physical and laboratory findings were recorded. The use of ultrasonography, computed tomography scan, chest radiograph, and serum antibodies was noted, as well as the final ED diagnosis. RESULTS: Seventy-five patients were reviewed; mean patient age was 35.5 years, 80% were male, and Mexico was the country of origin for 64%. The most common complaint was fever (77%), followed by abdominal pain (72%), which was most often located in the right upper quadrant. Cough (16%), chest pain (19%), and chest radiographic abnormalities (57%) were also common. The majority of patients (69%) had symptoms for less than 13 days. The WBC count was the most consistent laboratory abnormality (83%), whereas the liver aminotransferase, alkaline phosphatase, and bilirubin levels were often normal. Most patients received their diagnoses on the basis of ultrasonography (85%), followed by a confirmatory serum antibody titer (88%). The diagnosis of amebic liver abscess was correctly made in the ED in 31.5% of the patients, with the most common misdiagnoses being cholecystitis (16.4%), hepatitis (12.3%), and pneumonia (9.6%). CONCLUSION: Patients with amebic liver abscess do present to EDs in the southwestern United States, especially in areas with a high immigrant population from endemic areas. Patients with complaints of fever and right upper quadrant abdominal pain, especially men of Hispanic origin, warrant a high degree of vigilance. Whereas most laboratory studies are unhelpful, the diagnosis can often be made in the ED by means of a bedside ultrasonographic test. Treatment should be initiated with metronidazole with disposition to an inpatient medical service.  相似文献   
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This study investigated the effect of alcohol consumption and smoking during pregnancy on the fatty acid composition of the infants. A total of 40 very-low-birth-weight (VLBW) infants, weighing between 750 and 1500 g, were enrolled in the study after being hospitalized and ventilated for respiratory distress syndrome (RDS). Maternal and infant demographic information was recorded. Questions regarding maternal smoking (none, < 10 and > or = 10 cigarettes/d) and alcohol consumption (none, occasionally, moderate and severe) were recorded. Erythrocyte membrane (EMB; n = 40) total fatty acid analyses were performed at birth (baseline) and on days 14 and 28 postnatally. During pregnancy, 42% of mothers consumed alcohol and 50% smoked. At birth, infants of mothers who smoked and consumed alcohol during pregnancy, had significantly higher blood docosahexaenoic acid (DHA; p < 0.05) than infants of mothers who abstained from both alcohol and smoking. The consequences of this finding remain unknown.  相似文献   
998.

Purpose:

To investigate the three‐dimensional (3D) fast‐recovery fast spin‐echo accelerated (FRFSE‐XL) sequence as a new application for measuring the intraorbital optic nerve (ION) mean cross‐sectional area in vivo and to determine its value within a commonly used high resolution imaging protocol.

Materials and Methods:

The entire ION was scanned in nine healthy volunteers (mean age 32 ± 4 years) using the 3D FRFSE‐XL sequence and a commonly used high resolution short‐echo fast fluid‐attenuated inversion‐recovery (sTE fFLAIR) sequence with identical slice locations at 1.5T. The mean cross‐sectional area from both sequences was measured on a slice‐by‐slice basis from 3 mm behind the globe to the orbital apex. The reproducibility of both techniques was assessed from repeated scans (scan‐rescan) and repeated image analysis (intraobserver).

Results:

Measurement of the mean cross‐sectional area of the anterior 9 mm segment of the ION was only possible using the 3D FRFSE‐XL sequence with a mean area of 11.6 ± 2.2 mm2 (scan rescan COV = 3.3 ± 1.5, intraobserver COV = 2.4 ± 0.02) whereas the remainder segment of the ION (i.e., 9 mm behind the globe to the orbital apex) could only be measured with the use of the sTE fFLAIR with a mean area of 8.5 ± 1.7 mm2 (scan rescan COV = 4.9 ± 2.5 and intraobserver COV = 3.70 ± 0.03).

Conclusion:

The 3D FRFSE‐XL allows fast and reproducible measurement of the cross‐sectional area of the anterior 9mm segment of the ION, which is not possible using commonly used imaging sequences due to image degradation from motion, and is of complementary value to the existing imaging protocol for ION atrophy quantification. J. Magn. Reson. Imaging 2010;31:1486–1491. © 2010 Wiley‐Liss, Inc.  相似文献   
999.
Neutrophils (PMNs) obtained by nasal lavage were counted to determine if ozone, an oxidant air pollutant, induces an acute inflammatory response in the upper respiratory tract (URT) of humans. Background data were obtained by the nasal lavages from 200 nonexperimentally exposed subjects. Then, using a known inflammatory agent for the URT, rhinovirus-type 39, the induction, peak, and resolution of an acute inflammatory response was shown to be documented by the nasal lavage PMN counts. To determine if ozone induces this response, 41 subjects were exposed to either filtered air or 0.5 ppm ozone for 4 hr, on 2 consecutive days. Nasal lavages were taken pre-, immediately post each exposure, and 22 hr following the last exposure. Lavage PMN counts increased significantly (p = .005) in the ozone-exposed group, with 3.5-, 6.5-, and 3.9-fold increases over the air-exposed group at the post 1, pre 2, and post 2 time points, respectively. Ozone induces an inflammatory response in the URT of humans, and nasal lavage PMN counts are useful to assay the inflammatory properties of air pollutants.  相似文献   
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