| 1. |
- Liu, Y X, et al.
(författare)
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Coordinated regulation of tissue type plasminogen activator and plasminogen activator inhibitor type-1 gene expression in hypophysectomized rat ovaries during GnRHa-induced ovulation.
- 1994
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Ingår i: Science in China. Series B, Chemistry, life sciences & earth sciences. - 1001-652X. ; 37:7, s. 820-30
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Tidskriftsartikel (refereegranskat)abstract
- In this study we have demonstrated that both granulosa and theca-interstitial cells of hypophysectomized rat ovaries are capable of synthesizing tPA and PAI-1. Injection of a GnRH agonist can markedly induce these gene expressions in the ovary in a cell-specific and time-coordinated manner, so that a surge of tPA mRNA and its activity in both granulosa and theca-interstitial cells was obtained just prior to ovulation. Theca-interstitial cells make PAI-1 become the most active in the ovary. Both the amount PAI-1 mRNA and its activity in the cells reach the maximum level 6 h before the tPA peak. By contrast, granulosa cells produce only a little amount of PAI-1 (most increase tPA activity), and both PAI-1 mRNA and activity in the cells reach the maximum after ovulation. The coordinated regulation of tPA and PAI-1 in the ovary may fine-tune the peak of tPA activity which may be important for the regulation of the ovulatory process. The changes of tPA and PAI-1 in the ovarian cells of hypophysectomized rats during GnRHa-induced ovulation are similar to that in intact rats during hCG-induced ovulation, suggesting that the ovulatory process can be modulated by different regulatory signals mediated by influencing the coordinated expression of both tPA and PAI-1.
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| 2. |
- Liu, Y X, et al.
(författare)
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Hormonal regulation of expression of tissue type plasminogen activator and plasminogen activator inhibitor type 1 in cultured rat granulosa cells.
- 1994
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Ingår i: Science in China. Series B, Chemistry, life sciences & earth sciences. - 1001-652X. ; 37:3, s. 271-9
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Tidskriftsartikel (refereegranskat)abstract
- In the present study, gonadotropin and gonadotropin-releasing hormone (GnRH) regulation of tPA and PAI-1 expression in PMSG-primed granulosa cells has been investigated. (i) Addition of gonadotropins (FSH and LH) and GnRH agonist (GnRHa) or PMA to the culture increases tPA activity; FSH (or LH) plus GnRHa (or PMA) in the culture further enhances the enzyme production to such an extent that a more obvious effect than the additive effect caused by these hormones used alone has been observed; (ii) in contrast, FSH and LH decrease PAI-1 activity, whereas GnRHa and PMA alone markedly increase PAI-1 mRNA level and PAI-1 activity. Because FSH and LH stimulate tPA production and have no significant effect on PAI-1 mRNA induction, the observed inhibition of PAI-1 activity by gonadotropins may be due to the occurrence of neutralization of PA and PAI-1 proteins in the conditioned media by the formation of complexes between PA and PAI-1; (iii) increases in PAI-1 mRNA level and activity by GnRH and PMA are completely inhibited by the co-addition of FSH or LH to the culture. It is, therefore, suggested that the mechanism of gonadotropin and GnRHa regulation of tPA and PAI-1 expression in granulosa cells is different.
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| 3. |
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| 4. |
- Abeysekera, John, et al.
(författare)
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Body sizes and other human factors differences between Swedish and foreign students in Swedish universities
- 1994
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Ingår i: Ergonomics for Quality Life. - : PPCOE. ; , s. 420-423
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Konferensbidrag (refereegranskat)abstract
- Past studies have shown large differences in body size between people of Industrialized Countries (ICs) and Industrially Developing Countries (IDCs). These differences can have negative effects on the usage of technology which IDCs today acquire to a great extent from ICs. At the same time, the number of students from IDCs seeking education and training in universities in ICs is increasing. This paper reports on the impact of human factors differences particularly body size differences between foreign and local students on the use of university facilities, based on anthropometric and questionnaire surveys carried out on a small scale by foreign graduate students of Lulea University, Sweden. The study revealed large differences in body sizes between local and foreign students. The questionnaire survey of foreign students showed that there are other significant human factors differences such as the use of a foreign language, viz. Swedish which is unique to Scandinavia, and the exposure to long cold winters. Whether these differences in human factors influence the acquisition of knowledge or learning capacity of foreign students is worth further investigation.
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| 5. |
- Allen, Marie, et al.
(författare)
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A comprehensive polymerase chain reaction-oligonucleotide typing system for the HLA class I A locus
- 1994
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Ingår i: Human Immunology. - : Elsevier BV. - 0198-8859 .- 1879-1166. ; 40:1, s. 25-32
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Tidskriftsartikel (refereegranskat)abstract
- A comprehensive system for genetic typing of the HLA class I A locus is described, based on PCR amplification and typing with nonradioactively labeled SSO probes. Exons 1-3 of the A locus are amplified and typing is performed with a set of 30 nonradioactively labeled oligonucleotide probes. This system resolves 34 of 39 known alleles and 561 (94%) of 595 possible genotypes. Among a sample of 354 individuals from Sweden and China, 97.5% of the genotypes were resolved. Probes were directed preferentially at replacement substitutions in foreign antigen-binding sites, in order to detect not only the known alleles but also new combinations of polymorphic motifs, indicative of previously unrecognized alleles. Three individuals were found with a new combination of polymorphic motifs, suggesting the presence of at least one previously undescribed allele in the populations sampled. This typing system is useful for disease association studies, tissue typing, and in forensic medicine.
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| 6. |
- Amann, F., et al.
(författare)
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A search for murarregamma at the level of 10-13
- 1991
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Ingår i: Proceedings of the 25th International Conference on High Energy Physics. - 9810024347 ; , s. 1070-1071
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Konferensbidrag (refereegranskat)abstract
- The MEGA experiment, which is a search for the decay murarregamma with a branching ratio sensitivity of about 10-13, employs highly modular, fast detectors, state-of-the-art electronics, and a staged trigger with on-line filters. The detectors are contained in a 1.5-T solenoidal field produced by a superconducting magnet. Positrons are confined to the central region and are measured by a set of thin MWPCs. Photons are measured by one of four layers of pair spectrometers in the outer region. Most aspects of the design have been validated in engineering runs; data taking will begin in 1990 with much of the electron arm and one pair spectrometer layer installed.
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| 7. |
- Barnes, Leslie A, et al.
(författare)
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Bond length, dipole moment, and harmonic frequency of CO
- 1993
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Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 98:5, s. 3972-3977
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Tidskriftsartikel (refereegranskat)abstract
- A detailed comparison of some properties of CO is given, at the modified coupled-pair functional, single and double excitation coupled-cluster (CCSD), and CCSD(T) levels of theory (including a perturbational estimate for connected triple excitations), using a variety of basis sets. With very large one-particle basis sets, the CCSD(T) method gives excellent results for the bond distance, dipole moment, and harmonic frequency of CO. In a [6s 5p 4d 3f 2g 1h] + (1s 1p 1d) basis set, the bond distance is about 0.005a0 too large, the dipole moment about 0.005 a.u. too small, and the frequency about 6 cm-1 too small, when compared with experimental results.
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| 8. |
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| 9. |
- Dou, S.X., et al.
(författare)
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Improvement of critical current density in the Bi-Pb-Sr-Ca-Cu-O system through hot isostatic pressing
- 1990
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Ingår i: Physica. C, Superconductivity. - 0921-4534 .- 1873-2143. ; 167:5-6, s. 525-528
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Tidskriftsartikel (refereegranskat)abstract
- The effects of hot isostatic pressing (HIPing) on densification and the superconducting properties of the Bi-Pb-Sr-Ca-O system were investigated. A relative density up to 95% and a critical current density greater than 1100 A/cm2 at 77 K were achieved through HIPing at 650°C for 2 h under 200 MPa argon. Under these conditions, the product gave a value of Jc four times that without HIPing. To was unaffected by HIPing for samples encapsulated with a combination of glass and silver tubes. However, To was suppressed from 103 K to 86 K for samples encapsulated with stainless steel and silver tubes while Jc increased from 260 A/ cm2 to 1086 A/cm2 during HIPing, indicating that the weak links were significantly improved. A new minor phase, having a composition of Bi/Pb/Sr/Ca/Cu=0.58/2.8/3.0/2.1/1.1, was observed in HIPed samples but its effect on Jc is not clear
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| 10. |
- Dou, S.X., et al.
(författare)
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Microstructure and flux pinning in superconducting Bi-Pb-Sr-Ca-Cu-O wires
- 1990
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Ingår i: Physica. C, Superconductivity. - 0921-4534 .- 1873-2143. ; 172:1-2, s. 63-70
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Tidskriftsartikel (refereegranskat)abstract
- The critical current density (Jc) of Ag-clad Bi-Pb-Sr-Ca-Cu-O wire has been measured to be 1.2×104 A/cm2 at 77 K in zero field. The high Jc is attributed to a combination of elimination of the poisoning effect of Ag on superconductivity, grain alignment, and enhancement of flux pinning. Jc-H dependence was significantly improved in the Ag-clad tape, which has a Jc of 1.0×103 A /cm2 at 77 K and 4000 Oe, while the Jc of the sintered pellet drops two orders of magnitude at only 100 Oe. A pronounced anisotropy in Jc under high magnetic field is attributed to the grain alignment. Planar defects, such as heavy stacking faults parallel to the a-b plane in the rolled tape, are considered to be effective pinning centres.
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