1. |
- Amini, Hashem, et al.
(författare)
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Comparison of ultrasound and autopsy findings in pregnancies terminated due to fetal anomalies
- 2006
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Ingår i: Acta Obstetricia et Gynecologica Scandinavica. - : Wiley. - 0001-6349 .- 1600-0412. ; 85:10, s. 1208-1216
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Tidskriftsartikel (refereegranskat)abstract
- Objective. To compare antenatal diagnoses with autopsy findings in pregnancies terminated after ultrasound detection of fetal anomalies. A second aim was to study the quality of antenatal fetal diagnosis over time. Design. Retrospective, multicenter study over two consecutive six-year periods in Uppsala and Stockholm. Setting. Cases were identified through fetal autopsy reports. Subjects. Three hundred and twenty-eight fetuses from pregnancies terminated between 1992 and 2003 because of ultrasonographically diagnosed anomalies. Main outcome measures. The findings at the last ultrasound examination were compared with the autopsy reports. Results. In 299 cases (91.2%) ultrasound findings either exactly matched or were essentially similar to the autopsy findings. In 23 cases (7%) ultrasound findings were not confirmed at autopsy, but the postnatal findings were at least as severe as the antenatal ones. In six cases (1.8%) termination was performed for an anomaly which proved to be less severe than was predicted by ultrasound. The number of such cases was the same in both six-year periods, while the total number of cases increased from 113 in the first to 215 in the second period. Fetal examination provided further diagnostic information in 47% of the cases. In 10% a syndrome was disclosed. Conclusion. Termination of pregnancy was not always based on a correct antenatal diagnosis. All fetuses but one from terminated pregnancies had evident anomalies. In six cases (1.8%) the decision to terminate was based on suboptimal prognostic and diagnostic information. Fetal autopsy by an experienced perinatal pathologist is essential to provide a definitive diagnosis.
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2. |
- Antonsson, H, et al.
(författare)
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VIBRATIONAL MOTION AND GEOMETRICAL STRUCTURE IN ADSORBED CO STUDIED BY CORE LEVEL PHOTOELECTRON-SPECTROSCOPY
- 1990
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Ingår i: Journal of Electron Spectroscopy and Related Phenomena. - 0368-2048. ; 54, s. 601-613
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Tidskriftsartikel (refereegranskat)abstract
- High resolution core level spectra from CO adsorbed on clean and hydrogen precovered Ni(100) and CO adsorbed on Cu(100) are presented. The core level binding energy is shown to be sensitive to the adsorption site. Cluster calculations reproduce the general trend of the binding energy shifts between the on top and hollow sites of CO/Ni(100). In the coadsorption system CO/H/Ni(100) three different adsorption sites have been observed with a maximum binding energy shift of 2.6 eV for the Ols level. The temperature dependence of the Cls and Ols line profiles in CO/Ni(100) has been carefully investigated. The temperature dependent broadening is due to thermal excitations of frustrated translations parallel to the surface. The spectra from CO on Cu(100) show no temperature dependence below 200K.
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3. |
- Christensson, Bengt, et al.
(författare)
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Åtgärder för säker hantering av nanofibrer vid komposittillverkning
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Inför användning av nanomaterial i en ny produkt, har mätningar gjorts för att studera hur nanopartiklar sprids i arbetsmiljön och vilka halter som kan förväntas vid användning av kolnanofibrer (främst kolnanotuber) och järnoxidnanopartiklar. Mätningarna har använts som underlag för utvärdering av åtgärder med målet att ge råd om säker hantering av nanofibrer och nanopartiklar. Kolnanotuber är små och tunna, liksom fibriller från asbest. Det finns misstankar om att kolnanotuber liksom asbest kan orsaka cancer, bland annat mesoteliom. Det är därför viktigt att kolnanotuberna hanteras på ett kontrollerat sätt. Gränsvärden har förslagits för kolnanofibrer i arbetsmiljön. Föreslagna gränsvärden varierar från 2,5 µg/m3 till 100 µg/m3. För kolnanofibrer föreslås dessutom ett gränsvärde baserat på antal fibrer 0,01 f/ml (fibrer/ml luft). Beroende på kolnanofibrernas struktur diskuteras olika gränsvärden. Mätningar vid hantering av små mängder nanofibrer och nanopartiklar visar att halterna kan hållas låga om kolnanofibrerna hanteras i glovebox som placerats i dragskåp eller liknande välventilerat utrymme. Föreslagna gränsvärden är så låga att sluten hantering krävs för att gränsvärdena inte ska överskridas. Vid slipning fångades damm och nanopartiklar in om det fanns effektiva integrerade utsug i kombination med platsventilation. Utan väl fungerande ventilation blev halten nanofibrer och -partiklar snabbt mycket hög. Vid sanering minskade damningen om saneringen utfördes vått och med tillsats av dammbindningsmedel. Vid ovarsam hantering kan halterna också bli höga liksom vid tillfälliga spill. Inom projektet har flera olika mätmetoder testats och använts parallellt. Mätningarna har gett en god förståelse för hur nanopartiklar kan mätas men även för hur mätdata kan tolkas samt betydelsen av att ha kontroll på andra nanopartikel-källor som kan störa mätningarna. Mätningarna visar också att produktutveckling pågår som minskar nanopartiklarnas tendens att agglomerera, vilket kan leda till ökande exponering för nanopartiklar.
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4. |
- Hedelin, Henrik, 1975, et al.
(författare)
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Stability in Pelvic Triple Osteotomies in Children Using Resorbable PLGA Screws for Fixation
- 2021
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Ingår i: Journal of Pediatric Orthopaedics. - : Ovid Technologies (Wolters Kluwer Health). - 0271-6798. ; 41:9
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Tidskriftsartikel (refereegranskat)abstract
- Background: The triple pelvic osteotomy (TPO) is a major redirectional osteotomy used to improve the acetabular coverage of the femoral head in selected pediatric patients with hip disorders. Traditionally the iliac osteotomy is stabilized by metal screws that require a second surgery for removal. Despite favorable results for both adults and children in related pelvic osteotomies, resorbable implants have not previously been used for TPOs. This study aims to suggest a novel modified TPO surgical method in children using resorbable poly lactic-co-glycolic acid (PLGA) screws for fixation and to radiographically evaluate the postoperative stability achieved by these implants in a case series. Methods: All patients (n=11) with dysplasia of the hip (2), Perthe disease (5), or Down syndrome (4), who underwent primary TPO surgery during 2013 to 2019, using resorbable PLGA screws for fixation were included. The stability of the osteotomy was evaluated in the postoperative radiograph series using the acetabular index, migration percentage, Sharp's angle and the center-edge angle. The osteotomy angle was introduced as a parameter to confirm the postoperative integrity of the achieved correction. All cases were evaluated until radiographic healing of the iliac osteotomy. Hospital notes were analyzed for complications or local reactions in relation to the implants. Results: In all studied hips, the overall achieved correction was well maintained. The mean (SD) correction achieved, from the preoperative images to the last measurable postoperative image, was a 16.7 degrees decrease for Sharp angle, a 20.9 degrees decrease in acetabular index and a 24.7 degrees increase for the center-edge angle, respectively. There were no complications related to the bioabsorption of the implants. Conclusion: The present findings suggest that the modified TPO method, using resorbable PLGA screws, provides sufficient stability and appears to be a promising alternative to traditional TPO. Avoiding implant removal is a major benefit in a pediatric population. Resorbable screws enable the surgeon to place implants with more degrees of freedom since later implant removal is not a limiting factor.
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5. |
- Håkansson, M., et al.
(författare)
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The crystal structure of staphylococcal enterotoxin H : Implications for binding properties to MHC class II and TcR molecules
- 2000
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Ingår i: Journal of Molecular Biology. - : Elsevier BV. - 0022-2836. ; 302:3, s. 527-537
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Tidskriftsartikel (refereegranskat)abstract
- The X-ray structure of the superantigen staphylococcal enterotoxin H (SEH) has been determined at 1.69 Å resolution. In this paper we present two structures of zinc-free SEH (apoSEH) and one zinc-loaded form of SEH (ZnSEH). SEH exhibits the conventional superantigen (SAg) fold with two characteristic domains. In ZnSEH one zinc ion per SEH molecule is bound to the C-terminal β-sheet in the region implicated for major histocompatibility complex class II (MHC class II) binding in SEA, SED and SEE. Surprisingly, the zinc ion has only two ligating amino acid residues His206 and Asp208. The other ligands to the zinc ion are two water molecules. An extensive packing interaction between two symmetry-related molecules in the crystal, 834 Å2/molecule, forms a cavity that buries the zinc ions of the molecules. This dimer-like interaction is found in two crystal forms. Nevertheless, zinc-dependent dimerisation is not observed in solution, as seen in the case of SED. A unique feature of SEH as compared to other staphylococcal enterotoxins is a large negatively charged surface close to the Zn2+ site. The interaction of SEH with MHC class II is the strongest known among the staphylococcal enterotoxins. However, SEH seems to lack a SEB-like MHC class II binding site, since the side-chain properties of structurally equivalent amino acid residues in SEH and those in SEB-binding MHC class II differ dramatically. There is also a structural flexibility between the domains of SEH. The domains of two apoSEH structures are related by a 5°rotation leading to at most 3 Å difference in C(α) positions. Since the T-cell receptor probably interacts with both domains, SEH by this rotation may modulate its binding to different TcR Vβ-chains. (C) 2000 Academic Press.
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6. |
- Johanson, Per-Erik, et al.
(författare)
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Early Subsidence Predicts Failure of a Cemented Femoral Stem With Minor Design Changes
- 2016
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Ingår i: Clinical Orthopaedics and Related Research. - : Ovid Technologies (Wolters Kluwer Health). - 0009-921X. ; 474:10, s. 2221-2229
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Tidskriftsartikel (refereegranskat)abstract
- Radiostereometry (RSA) measurements of early micromotion can predict later failure in hip and knee prostheses. In hip implants, RSA has been particularly helpful in the evaluation of composite-beam stem designs. The Spectron EF Primary stem (Smith & Nephew, London, UK) has shown inferior performance compared with its predecessors in both clinical studies and registry reports. Early RSA studies have shown somewhat greater subsidence for the Spectron EF Primary stem compared with the earlier Spectron EF, but still within boundaries considered to be safe. Our primary research question was whether stem subsidence and rotation for this stem design measured with RSA at 2 years can predict later stem failure. A secondary question was whether high femoral stem offset and small stem sizes, both features specific to the Spectron EF Primary stem compared with its predecessors, are associated with stem failure rate. Two hundred forty-seven hips (209 patients with median age 63 years [range, 29-80 years], 65% female, and 77% primary osteoarthritis) with a valid RSA examination at 2 years were selected from four different RSA studies (totaling 279 hips in 236 patients) in our department. The studies were primarily aimed at evaluating cup fixation, bone cement, and polyethylene types. All study patients received a cemented Spectron EF Primary stem. The selected hips had complete followup until stem failure, death, or the end of the followup period. Stem failure was defined as revision of a loose femoral stem or radiological failure with significant osteolysis in Gruen zones 2 to 6. Cox regression analyses were performed to evaluate if stem subsidence and rotation after 2 years, adjusted for age, sex, stem size, standard/high stem offset, and conventional/highly crosslinked polyethylene, could predict later clinical aseptic failure of the stem. We identified 32 stem failures (27 revisions, five radiological failures) at 14 years median followup (range, 3-18 years). Ten-year stem survival was 94% (95% confidence interval [CI], 90%-96%). Stem subsidence at 2 years (adjusted hazard ratio [HR], 6.0; 95% CI, 2.5-15; p < 0.001) and retrotorsion of the stem (adjusted HR, 1.7; 95% CI, 1.1-2.5; p = 0.018) were associated with later stem failure. Further risk factors were male sex (subsidence analysis HR, 6.9; p > 0.001), use of the two smallest stem sizes (HRsize 1, 8.0; p > 0.001, HRsize 2, 1 [reference], HRsize 3+, 0.06; p = 0.035), and the high offset option (HR, 3.1; p = 0.005). Stem subsidence and retrotorsion at 2 years can predict later failure in the Spectron EF Primary stem, consistent with earlier findings on composite-beam cemented stems. Small stem size and high-offset stems comprise the main group of underperforming stems. We recommend that premarket small-scale RSA studies be performed after any design change to a THA femoral component, because even seemingly minor design changes may unexpectedly result in inferior performance.
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7. |
- Linton, Johan, 1966, et al.
(författare)
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Arkitekturens ordning
- 2008
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Ingår i: Psykoanalytisk Tid/Skrift. - 1650-7398.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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8. |
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9. |
- Nore, Beston F, et al.
(författare)
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Identification of phosphorylation sites within the SH3 domains of Tec family tyrosine kinases
- 2003
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Ingår i: Biochimica et Biophysica Acta. - 0006-3002 .- 1878-2434. ; 1645:2, s. 123-132
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Tidskriftsartikel (refereegranskat)abstract
- Tec family protein tyrosine kinases (TFKs) play a central role in hematopoietic cellular signaling. Initial activation takes place through specific tyrosine phosphorylation situated in the activation loop. Further activation occurs within the SH3 domain via a transphosphorylation mechanism, which for Bruton's tyrosine kinase (Btk) affects tyrosine 223. We found that TFKs phosphorylate preferentially their own SH3 domains, but differentially phosphorylate other member family SH3 domains, whereas non-related SH3 domains are not phosphorylated. We demonstrate that SH3 domains are good and reliable substrates. We observe that transphosphorylation is selective not only for SH3 domains, but also for dual SH3SH2 domains. However, the dual domain is phosphorylated more effectively. The major phosphorylation sites were identified as conserved tyrosines, for Itk Y180 and for Bmx Y215, both sites being homologous to the Y223 site in Btk. There is, however, one exception because the Tec-SH3 domain is phosphorylated at a non-homologous site, nevertheless a conserved tyrosine, Y206. Consistent with these findings, the 3D structures for SH3 domains point out that these phosphorylated tyrosines are located on the ligand-binding surface. Because a number of Tec family kinases are coexpressed in cells, it is possible that they could regulate the activity of each other through transphosphorylation.
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10. |
- Rowa, Per, et al.
(författare)
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Automated Malaria Parasite Detection
- 1977
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- A system for malaria parasite detection in thin blood-smears is presented. Sample slides prepared with standard methods are accepted. A low-cost TV-camera mounted on an ordinary microscope with a computer controlled stage is used as a picture sensor. Frames, digitized in windows of 64 x 64 pixels are fed into a special purpose picture processor at normal frame rate (25 frames/sec). In the picture processor measurements are made on the images at high speed. The classification problem is split into different levels each having different characteristics such as different sampling density. Four classes, three of which are different types of malaria parasites, are recognized. As a whole the classification is best labelled as a sequential pattern recognition procedure.In its preliminary version the system has been run at a speed comparable to that of a human operator, that is l 500 cells per minute. A test on 80 000 cells gave 25 false negatives out of 283 parasites (9%) and 41 false positives (0.05%).
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