| 1. |
|
|
| 2. |
- Abdo, A. A., et al.
(författare)
-
DISCOVERY OF HIGH-ENERGY GAMMA-RAY EMISSION FROM THE BINARY SYSTEM PSR B1259-63/LS 2883 AROUND PERIASTRON WITH FERMI
- 2011
-
Ingår i: Astrophysical Journal Letters. - 2041-8205. ; 736:1, s. L11-
-
Tidskriftsartikel (refereegranskat)abstract
- We report on the discovery of >= 100 MeV gamma-rays from the binary system PSR B1259-63/LS 2883 using the Large Area Telescope (LAT) on board Fermi. The system comprises a radio pulsar in orbit around a Be star. We report on LAT observations from near apastron to similar to 128 days after the time of periastron, t(p), on 2010 December 15. No gamma-ray emission was detected from this source when it was far from periastron. Faint gamma-ray emission appeared as the pulsar approached periastron. At similar to t(p) + 30 days, the >= 100 MeV gamma-ray flux increased over a period of a few days to a peak flux 20-30 times that seen during the pre-periastron period, but with a softer spectrum. For the following month, it was seen to be variable on daily timescales, but remained at similar to(1-4) x 10(-6) cm(-2) s(-1) before starting to fade at similar to t(p) + 57 days. The total gamma-ray luminosity observed during this period is comparable to the spin-down power of the pulsar. Simultaneous radio and X-ray observations of the source showed no corresponding dramatic changes in radio and X-ray flux between the pre-periastron and post-periastron flares. We discuss possible explanations for the observed gamma-ray-only flaring of the source.
|
|
| 3. |
|
|
| 4. |
- Moberg, K, et al.
(författare)
-
Radiological review of incidence breast cancers
- 2000
-
Ingår i: Journal of medical screening. - : SAGE Publications. - 0969-1413 .- 1475-5793. ; 7:4, s. 177-183
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives To examine the rate of incidence cancers detectable on review of previous screening mammograms using two reviewing methods. To compare the results with a previous study of interval cancers using the same reviewing methods. Setting Almost 50 000 women are regularly invited for service screening at Stockholm Söder Hospital. From 1989 to 1993, 119 women were identified with breast cancer detected at screening and the previous round attendance (incidence cancer). Methods Screening mammograms, obtained before detection of the incidence cancers, were reviewed first mixed with other screening images (ratio 1:8) and then non-mixed. Reviewers from the screening unit responsible for the mammograms as well as reviewers from other units interpreted all images by both single and double reading. Results The proportion detected on retrospective review varied between 5% and 50% depending on the review method used and the number of reviewers included to classify a case as truly identified. Generally more cancers were detected when non-mixed samples of mammograms were reviewed than when mixed samples were reviewed (mean increase 23%) and when interpreted by double reading compared with single reading (mean increase 14%). Conclusions In an experimental retrospective set up, fewer incidence cancers were identified in mixed than in non-mixed review. Generally more incidence cancers were identified on review (22%) than previously reported for interval cancers (14%), probably reflecting differences in tumour biology and growth. How many women with potentially visible incidence cancers would have benefited from earlier tumour detection still needs to be evaluated.
|
|
| 5. |
- Moberg, K, et al.
(författare)
-
Two models for radiological reviewing of interval cancers
- 1999
-
Ingår i: Journal of medical screening. - : SAGE Publications. - 0969-1413 .- 1475-5793. ; 6:1, s. 35-39
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives To compare two different review methods of examining how many of our interval cancers could be regarded as missed cases (overlooked and misinterpreted owing to observer's error). Setting A mass screening programme in Stockholm 1989–91, performed at five independent screening units. 107 846 women attended for screening (70.6% of those invited), and 207 women with interval breast cancers were identified. Interval cancers from two of the units, 104 cases, are reviewed in this study. Methods Screening examinations preceding the interval cancer diagnoses were reviewed both mixed with other screening images in a ratio 1:8 and non-mixed. Both internal reviewers (from the two units responsible for the screening mammograms) and external reviewers (from the other units) took part in the study. Results The proportion regarded as missed cases varied between 7% and 34%, depending on what review method was used, and on the number of reviewers included to identify a case as missed. Mixed reviewing reduced the number identified as missed cases by 50% compared with non-mixed reviewing. Whether the reviewer was internal or external made no difference to the results. Conclusions Comparing the rate of missed cases from different studies may be misleading unless the same review method is used. No difference in detection rate could be shown whether the radiologist reviewed images from his/her own screening unit or not. Most of our interval cancers were not regarded as missed cases by either of the two methods.
|
|
| 6. |
|
|
| 7. |
- Grundstrom, M., et al.
(författare)
-
Oak pollen seasonality and severity across Europe and modelling the season start using a generalized phenological model
- 2019
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697. ; 663, s. 527-536
-
Tidskriftsartikel (refereegranskat)abstract
- Oak pollen seasons are relatively unexplored in large parts of Europe despite producing allergens and being a common tree in both continental and northern parts. Many studies are concentrated only on the Iberian Peninsula. In this study, the seasonal pattern of oak pollen in Europe was analysed using 10 observation sites, ranging from Spain to Sweden. The magnitude of peaks and annual pollen integral together with season-length were studied and substantially higher pollen levels and longer seasons were found in Spain. Two northern sites in Denmark and Sweden showed high oak pollen peaks together with two sites in Spain and United Kingdom. The study also tested four common definitions of season start and applied a generalized phenological model for computing the start of the pollen season. The most accurate definition for a European-wide description of the observed oak pollen start was when the cumulative daily average pollen count reached 50 grains per cubic meter. For the modelling of the start a thermal time method based on Growing Degree Day (GDD) was implemented, utilizing daily temperatures and a generalized approach to identify model parameters applicable to all included sites. GDD values varied between sites and generally followed a decreasing gradient from south to north, with some exceptions. Modelled onsets with base temperatures below 7 degrees C matched well with observed onsets and 76% of the predictions differed <= 4 days compared to observed onsets when using a base temperature of 2 degrees C. Base temperatures above 7 degrees C frequently predicted onsets differing >1 week from the observed. This general approach can be extended to a larger area where pollen observations are non-existent. The presented work will increase the understanding of oak pollen variation in Europe and provide knowledge of its phenology, which is a critical aspect both for modelling purposes on large-scale and assessing the human exposure to oak allergens. (C) 2019 The Authors. Published by Elsevier B.V.
|
|
| 8. |
- Kern, M A, et al.
(författare)
-
Amyotrophic lateral sclerosis : Evidence for intact hepatocyte growth factor/MET signalling axis
- 2001
-
Ingår i: Cytokine. - : W B SAUNDERS CO. - 1043-4666 .- 1096-0023. ; 15:6, s. 315-319
-
Tidskriftsartikel (refereegranskat)abstract
- Hepatocyte growth factor (HGF) is a secreted cytokine which is expressed in the central nervous system (CNS) together with its specific receptor MET. Since HGF exerts strong neurotrophic activity including motoneurons, we have further analysed whether the HGF/MET axis is defective in patients with amyotrophic lateral sclerosis (ALS). Intrathecal HGF-secretion was measured in cerebrospinal fluid (CSF) from patients with amyotrophic lateral sclerosis and in controls without neurological diseases using a specific sandwich immunoassay (ELISA). MET-expression was analysed by immunohistology in spinal cord cross-sections of ALS patients and unaffected controls. The HGF concentrations in CSF were moderately but significantly increased in ALS patients compared to healthy controls (580 pg/ml vs 348 pg/ml). MET-protein was detectable in spinal cord motoneurons of patients with ALS as well as unaffected controls. The data demonstrate that ALS does not show a lack of the trophic signalling axis, HGF/MET, suggesting that the signalling system itself is not affected. The moderate increase in HGF-secretion may represent a compensatory effect.
|
|
| 9. |
|
|
| 10. |
|
|
| 11. |
|
|
| 12. |
- Sjogren, M., et al.
(författare)
-
Decreased CSF-ß-amyloid 42 in Alzheimer's disease and amyotrophic lateral sclerosis may reflect mismetabolism of ß-amyloid induced by disparate mechanisms
- 2002
-
Ingår i: Dementia and Geriatric Cognitive Disorders. - : S. Karger AG. - 1420-8008 .- 1421-9824. ; 13:2, s. 112-118
-
Tidskriftsartikel (refereegranskat)abstract
- Both tau and ß-amyloid 42 (Aß42) have been implicated in Alzheimer's disease (AD) and tau alone in frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). These proteins can be measured in the cerebrospinal fluid (CSF), differences from normal CSF levels may reflect pathophysiological mechanisms. Using ELISAs, we investigated the levels of total CSF-tau (here referred to as tau), phosphorylated CSF-tau (phospho-tau), and Aß42 in patients with AD (n = 19), FTD (n = 14), ALS (n = 11) and Parkinson's disease (PD, n = 15) and in age-matched controls (n = 17). Both CSF-tau and CSF-phosphotau were increased in AD compared with FTD (p < 0.001), ALS (p < 0.001), PD (p < 0.001) and controls (p < 0.001). CSF-Aß42 was markedly decreased in AD and ALS (both p < 0.001) and slightly decreased in FTD (p < 0.01) and PD (p < 0.05) compared with controls. Using CSF-phosphotau may improve the differentiation of AD from FTD and ALS in clinical praxis. Furthermore, decreased CSF-Aß42 levels may be common in neurode-generative disorders possibly reflecting changes in the metabolism of ß-amyloid or axonal degeneration. Copyright © 2002 S. Karger AG, Basel.
|
|
| 13. |
|
|
| 14. |
|
|
