| 1. |
- Behravan, G., et al.
(författare)
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THE INTERACTION OF ELLIPTICINE DERIVATIVES WITH NUCLEIC-ACIDS STUDIED BY OPTICAL AND H-1-NMR SPECTROSCOPY - EFFECT OF SIZE OF THE HETEROCYCLIC RING
- 1994
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Ingår i: Biopolymers. - : Wiley. - 0006-3525 .- 1097-0282. ; 34:5, s. 599-609
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Tidskriftsartikel (refereegranskat)abstract
- The DNA interaction of derivatives of ellipticine with heterocyclic ring systems with three, four, or five rings and a dimethylaminoethyl side chain was studied. Optical spectroscopy of drug complexes with calf thymus DNA, poly [(dA-dT).(dA-dT)], or poly [(dG-dC).(dG-dC)] showed a 10 nm bathochromic shift of the light absorption bands of the pentacyclic and tetracyclic compounds upon binding to the nucleic acids, which indicates binding by intercalation. For the tricyclic compound a smaller shift of 1-3 nm was observed upon binding to the nucleic acids. Flow linear dichroism studies show that the geometry of all complexes is consistent with intercalation of the ring system, except for the DNA and poly [(dG-dC).(dG-dC)] complexes of the tricyclic compound, where the average angle between the drug molecular plane and the DNA helix axis was found to be 65 degrees. One-dimensional H-1-nmr spectroscopy was used to study complexes between d(CGCGATCGCG)(2) and the tricyclic and pentacyclic compounds. The results on the pentacyclic compound show nonselective broadening due to intermediate chemical exchange of most oligonucleotide resonances upon drug binding. The imino proton resonances are in slow chemical exchange, and new resonances with upheld shifts approaching 1 ppm appear upon drug binding, which supports intercalative binding of the pentacyclic compound. The results on the tricyclic compound show more rapid binding kinetics and very selective broadening of resonances. The data suggest that the tricyclic compound is in an equilibrium between intercalation and minor groove binding, with a preference to bind close to the AT base pairs with the side chain residing in the minor groove. (C) 1994 John Wiley and Sons, Inc.
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| 2. |
- Bjarnason, Bjarni, et al.
(författare)
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The Bolmen project
- 1986
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Rapport (övrigt vetenskapligt/konstnärligt)
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| 3. |
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| 4. |
- Borg, Torgny, et al.
(författare)
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Stability prediction for the Zinkgruvan mine, central Sweden
- 1984
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Ingår i: Design and performance of underground excavations. - London : British Geotechnical Society. - 0727702114 ; , s. 113-121
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Konferensbidrag (refereegranskat)abstract
- The geomechanics of the Zinkgruvan Mine are presented. A new approach for performing rock stress measurements in open stopes and drifts was tested. An elastic FEM model and strain failure criteria were applied to predict the future condition of the mine. Limits of the strain failure criteria were based on strain values obtained from the model, observations of rock falls, and major failures in the mine. These limits were used to assess suitable panel height, sill pillar dimensions, and sequence delays for mining parallel ore bodies.
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| 5. |
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| 6. |
- Bylund, Bengt, et al.
(författare)
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Very low birth weight children at 9 years : School performance and behaviour in relation to risk factors
- 2000
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Ingår i: Prenatal and Neonatal Medicine. - 1359-8635 .- 1473-0774. ; 5:2, s. 124-133
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Tidskriftsartikel (refereegranskat)abstract
- Objectives To investigate the school performance and behavior of very low-birth-weight children in comparison with controls, and relate the findings to risk factors. Methods All children with birth weight below 1501 g (VLBW) and normal birth weight (NBW) controls, born in the south-east region of Sweden during a 15-month period in 1987-88, were enrolled in a prospective follow-up study; 81 % (n = 70) and 82% (n = 72), respectively, were re-examined at the age of 9 years regarding growth, neurological status, neurofunctional classification and academic achievement tests (Raven's matrices, mathematics, vocabulary, reading ability). The need for special education at school was assessed and four behavioral problem scores were also assessed (hyperactivity, fine motor skills, gross motor skills, social skills). Children with known handicaps were not re-examined. Results VLBW children were shorter and lighter than controls, and differed from them with regard to neurological functional classification. As a group, they produced poorer results in all academic achievement tests except vocabulary, and also in two out of four behavioral subscales (hyperactivity and fine motor skills). When the comparison was restricted to children with normal Raven scores, almost all the differences disappeared. VLBW children had more reading difficulties but were less often than expected defined as dyslexic compared to NEW children.
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| 7. |
- Doe, T.W., et al.
(författare)
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Determination of the state of stress at the Stripa Mine, Sweden
- 1982
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Ingår i: Workshop on Hydraulic Fracturing Stress Measurements. - Menlo Park, Calif.
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Konferensbidrag (refereegranskat)abstract
- The state of stress at the Stripa Mine has been measured both in a 381-m-deep hole drilled from the surface and in holes drilled from the drifts underground. Hydraulic fracturing and several overcoring methods have been used (Lulea triaxial gauge, CSIRO gauge, USBM gauge, Swedish State Power Board deep-hole Leeman triaxial gauge). Propagation of the hydraulic fractures underground was monitored acoustically in an attempt to determine the location and orientation of the fractures. The results of overcoring and hydraulic fracturing agree well, particularly for the magnitude and orientation of the greatest stress. The hydraulic-fracturing data were interpreted using first-breakdown pressures and tensile-strength values determined using statistical fracture mechanics. Shut-in pressure values were obtained from semi-logarithmic plots of the post-breakdown pressure decay and from reopening the fractures at low pumping rates.
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| 8. |
- Doe, T.W., et al.
(författare)
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Results and conclusions of stress measurements at Stripa
- 1983
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Konferensbidrag (refereegranskat)abstract
- This paper describes the results of stress measurements at Stripa, compares the results obtained by different techniques, and recommends a stress measurement program for a hard rock repository site. The state of stress at the Stripa Mine has been measured both in a 381-m-deep hole drilled from the surface and in holes drilled from the drifts underground. Hydraulic fracturing and several overcoring methods have been used (Lulea triaxial gauge, CSIRO gauge, USBM gauge, Swedish State Power Board deep-hole Leeman triaxial gauge). The results of overcoring and hydraulic fracturing agree well, particularly for the magnitude and orientation of the greatest stress. A recommended program for stress measurement at a repository site would include hydraulic fracturing and deep-hole overcoring in a deep hole drilled from surface, and overcoring (Lulea gauge and USBM gauge) and hydraulic fracturing from holes drilled from underground openings when access is available. Propagation of the hydraulic fractures should be monitored acoustically to determine their location and orientation.
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| 9. |
- Eriksson, M., et al.
(författare)
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BINDING OF DELTA- RU(PHEN)(3) (2+) AND LAMBDA- RU(PHEN)(3) (2+) TO D(CGCGATCGCG) (2) STUDIED BY NMR
- 1994
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Ingår i: Biochemistry. - : American Chemical Society (ACS). - 1520-4995 .- 0006-2960. ; 33:17, s. 5031-5040
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Tidskriftsartikel (refereegranskat)abstract
- The interactions of the Delta and Delta enantiomers of the chiral metal complex [Ru(phen)(3)](2+) (phen = 1,10-phenanthroline) with the oligonucleotide duplex [d(CGCGATCGCG)](2) have been studied with NMR and CD spectroscopy. From NOESY data it is shown that the interaction primarily takes place in the minor groove of the oligonucleotide which remains in a B-like conformation. The observed NOEs also provide evidence that the metal complexes preferentially bind to the central AT region. The observed AT specificity is more pronounced with the Delta as compared to the Delta enantiomer, which interacts with a larger part of the oligonucleotide. Furthermore, the NOESY data show that neither of the enantiomers binds by classical intercalation. This is also supported by a comparison study of the analogue [Ru(phen)(2)DPPZ](2+) (DPPZ = dipyrido[ 3,2-a:2',3'-c] phenazine) which intercalates in DNA. The NMR as well as the CD results show that the Delta and Delta enantiomers of [Ru(phen)(3)](2+) bind in different modes to [d(CGCGATCGCG)](2). Comparison of CD spectra of the metal complex in the presence of [d(CGCGATCGCG)](2), poly(dAdT).poly(dAdT), poly(dGdC).poly(dGdC), and calf thymus DNA suggests that these binding modes are independent of DNA sequence. The results are found to be compatible with binding of Delta-[Ru(phen)(3)](2+) by insertion of two phenanthroline ligands into the minor groove, causing minor distortions of the DNA structure, whereas the Delta enantiomer binds in a mode that leaves the DNA structure unaffected.
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| 10. |
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