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Occupational exposure to carcinogenic agents on the decks on six Norwegian crude oil tankers was examined in five harbors. The purpose of the study was to evaluate the need for improving the working environment on deck on these tankers. Technical arrangments and the work itself on the deck were observed during loading or unloading. Occupational monitoring was performed by active sampling of benzene, polyaromatic hydrocarbons, and some aldehydes. The crew answered a questionnaire concerning their work, use of protective equipment, and occurrence of acute symptoms. The levels of air-borne carcinogenic agents were low, probably due to closed loading systems on all tankers. However, the seamen reported discomfort during the work that may be related to other chemical agents in the cargo. The seamen were frequently painting with lead chromate paint without using personal protective equipment. This type of chemical exposure should be evaluated.  相似文献   
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Assessment of size and growth are key radiological factors in low-grade gliomas (LGGs), both for prognostication and treatment evaluation, but the reliability of LGG-segmentation is scarcely studied. With a diffuse and invasive growth pattern, usually without contrast enhancement, these tumors can be difficult to delineate. The aim of this study was to investigate the intra-observer variability in LGG-segmentation for a radiologist without prior segmentation experience. Pre-operative 3D FLAIR images of 23 LGGs were segmented three times in the software 3D Slicer. Tumor volumes were calculated, together with the absolute and relative difference between the segmentations. To quantify the intra-rater variability, we used the Jaccard coefficient comparing both two (J2) and three (J3) segmentations as well as the Hausdorff Distance (HD). The variability measured with J2 improved significantly between the two last segmentations compared to the two first, going from 0.87 to 0.90 (p?=?0.04). Between the last two segmentations, larger tumors showed a tendency towards smaller relative volume difference (p?=?0.07), while tumors with well-defined borders had significantly less variability measured with both J2 (p?=?0.04) and HD (p?<?0.01). We found no significant relationship between variability and histological sub-types or Apparent Diffusion Coefficients (ADC). We found that the intra-rater variability can be considerable in serial LGG-segmentation, but the variability seems to decrease with experience and higher grade of border conspicuity. Our findings highlight that some criteria defining tumor borders and progression in 3D volumetric segmentation is needed, if moving from 2D to 3D assessment of size and growth of LGGs.

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Abstract. Hepatitis B immune globulin has been prepared for clinical trials in Sweden. The relative amount of antibodies to the hepatitis B antigen recovered in the respective fractionation steps was evaluated by hemagglutination, immunoelectro-osmophoresis and radial immunodiffusion. About one third of the antibody amount present in the original plasma pool was recovered in fraction II. Hepatitis B antigen was neither demonstrated in the various fractionation steps nor in the final immune globulin preparation.  相似文献   
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The causal relationship between lower respiratory tract infections (LRIs) in early life and reduced lung function later in childhood is unsettled. Therefore, we assessed whether LRIs the first 2 yr of life influenced lung function development from birth to school age. In the prospective Oslo birth cohort, ‘the Environment and Childhood Asthma (ECA) study’ lung function was measured at birth in 802 infants by tidal flow volume loops and in 664 infants by passive respiratory mechanics and half yearly questionnaires, including LRI questions, were completed until 2 yr of age. The present study includes 607 children with information about LRIs the first 2 yr of life and successfully forced expiratory flow (FEF) volume measurements at the 10‐yr follow‐up assessment. At 10 yr of age, FEF at 50% of forced vital capacity (FEF50) (mean 95% confidence interval) was reduced in children with at least one bronchiolitis (85.0, 80.6–89.5, p = 0.020) or bronchitis (86.2, 82.6–89.8, p = 0.030) or ≥3 LRIs (83.4, 78.1–88.8, p = 0.017) when compared with no LRIs (90.6, 88.8–92.5) by 2 yr of life. The effects were significant in girls only when stratifying for gender. Among girls with later bronchiolitis compliance of the respiratory system (3.64, 3.17–4.10 vs. 4.18, 3.98–4.37, p = 0.031) and the ratio of time to peak tidal expiratory flow to total expiratory time (tPTEF/tE) measured at birth was significantly reduced (0. 26, 0.23–0.29 vs. 0.32, 0.30–0.33, p = 0.005) when compared with children with no LRIs. Change in lung function from birth (by tPTEF/tE) to 10 yr of age was not significantly associated with LRIs the first 2 yr of life, and LRIs by 2 yr of life were not significantly associated with lung function at 10 yr of age in regression analyses including lung function at birth and other possible predictors of lung function at 10 yr. In our study, LRIs during the first 2 yr of life did not impair lung function development from birth until 10 yr of age.  相似文献   
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The aim of this study was to describe and compare bone mineral density (BMD) development in Norwegian women and men aged 25-44 years in a population-based, longitudinal study. BMD was measured twice at distal and ultradistal forearm sites by single x-ray absorptiometry in 258 women and 147 men (mean follow-up time, 6.4 (standard deviation, 0.6) years). At the distal site, a small annual gain of approximately 0.1% became a small loss beginning at age 34 years in men and age 36 years in women. At the ultradistal site, BMD change was predicted by age in women only, and bone loss started at age 38 years. A high degree of tracking of BMD measurements was observed for both sexes and both sites, r > 0.93. Depending on total BMD change, participants were grouped into "losers", "nonlosers", and "gainers", and more than 6% lost more than the smallest detectable amount of BMD: > or =3.46% at the distal site and > or =5.14% at the ultradistal site. In both sexes, bone mineral content (grams) decreased, whereas area (centimeters squared) increased significantly in "losers" compared with "gainers". This finding might represent physiologic compensation preserving bone strength. No cohort effects were observed when 1994 and 2001 measures from similar age groups were compared.  相似文献   
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