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Fibrinolytic components after venous occlusion and concentrations of tissue plasminogen activator inhibitor were studied in 100 consecutive patients with confirmed recurrent deep vein thrombosis or pulmonary embolism. After 20 minutes of venous occlusion the fibrinolytic response was decreased in 33 patients, as measured both amidolytically with S-2251 and on fibrin plates. Two different mechanisms responsible for the poor fibrinolytic response could be distinguished. Twenty two of the patients in whom the response was poor released normal amounts of tissue plasminogen activator antigen, as assayed by immunoradiometric assay, but had appreciably increased concentrations of tissue plasminogen activator inhibitor. The 11 other patients in whom the response was poor had both low tissue plasminogen activator activities and low tissue plasminogen activator antigen concentrations but normal concentrations of tissue plasminogen activator inhibitor. The results show not only that defective synthesis or release of tissue plasminogen activator may be important in the pathogenesis of venous thrombosis but also that a large group of patients with thrombosis have an increased concentration of the inhibitor to tissue plasminogen activator. 相似文献
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R. Brändén T. Nilsson S. Styring 《Biochemical and biophysical research communications》1980,92(4):1297-1305
A sensitive and reliable method to determine the stereochemical composition of 3-phosphoglyceric acid is presented. Results obtained with this method show that 3-phosphoglyceric acid formed in the ribulose-1,5-bisphosphate carboxylase reaction is a mixture of 10% L-3-PGA and 90% D-3-PGA. 相似文献
27.
Katarina Nilsson Anna Flysjö Jennifer Davis Sarah Sim Nicole Unger Simon Bell 《The International Journal of Life Cycle Assessment》2010,15(9):916-926
Purpose
The goal of the study was to compare the environmental impact of butter and margarine. Altogether, seven products were studied in three European markets: UK, Germany and France. 相似文献28.
Kirsten Skamstrup Hansen Stefan Vieths Helle Vestergaard Per Stahl Skov Carsten Bindslev-Jensen Lars K. Poulsen 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,756(1-2)
The aim of the study was to investigate the possibility of a seasonal variation in reactivity to apples in 27 birch pollen allergic patients. Before and during the birch pollen season 1998, the patients were subjected to double-blind, placebo-controlled food challenges (DBPCFCs) with grated fresh Golden Delicious apple followed by an open food challenge with whole fresh apple. The clinical reactions elicited during the challenges were evaluated both by the patients and the investigators. Moreover, the skin reactivity and the in vitro reactivity to apple were evaluated by skin prick test (SPT), leukocyte histamine release (HR), measurement of specific IgE, and immunoblotting experiments. The sensitivity of the DBPCFC, when compared with the result of the open challenge, was 0.74 (14/19) before the season and 0.80 (16/20) during the season. None of the patients reacted to the blinded challenge without a subsequent reaction to the open challenge. One placebo reaction was registered both before and in season, but not in the same patient. The patient scores of the first positive challenges, and the maximal scores of each combined blinded and open challenge session, were significantly increased during the pollen season (P<0.05). The scores of the open challenge were significantly higher than the scores of the DBPCFC both before the season and during the in-season challenges (P<0.05). Specific IgE against Golden Delicious increased during season (P<0.05), while neither SPT, HR, nor immunoblotting experiments could confirm an increase in reactivity. In conclusion, the results of the oral challenge tests indicated an increase in clinical reactivity to apples during the birch pollen season in birch pollen allergic individuals. 相似文献
29.
Pernilla Christensen Frauke Ecke Per Sandström Mats Nilsson Birger Hörnfeldt 《Population Ecology》2008,50(2):169-179
There has been a long-term decline in spring and fall numbers of Clethrionomys rufocanus in boreal Sweden in 1971–2005. Previous studies on permanent sampling plots in the centre of 2.5 × 2.5 km landscapes suggested
that habitat fragmentation (sensu destruction) could have contributed to the decline. Therefore, we tested these findings
in a field study and compared trapping results on the central sampling plots of landscapes with a low degree of fragmentation
(LDF) and of “hot spot” type with trapping results in managed forest landscapes with a high degree of fragmentation (HDF).
We predicted that C. rufocanus would be more common on the LDF plots. We used our permanent plots supplemented with a new sample of plots, mainly of the
rare LDF type, inside or just outside the long-term study area. Very few voles were trapped on both plot types, and no difference
was found. However, a subsequent pilot study with trapping in a national park with large areas of pristine, unfragmented forest
yielded more voles than in the managed, more fragmented, areas. Consequently, the initial field study data and some other
recent data were also re-analysed from a “local patch quality” perspective. This alternative approach revealed the positive
importance of large focal patches of forest >60 years old and their content of old-growth (pine) forest (>100 years). Interestingly,
at the landscape level, the frequency distribution of patches of forest >60 years old, old-growth (>100 years), and especially
of old-growth pine forest (>100 years), relative to the properties of plots with C. rufocanus, suggested that there are few forest patches left that are suitable for C. rufocanus. Our current results suggest that habitat fragmentation cannot be excluded as a contributing cause to the long-term decline
of C. rufocanus in boreal Sweden. 相似文献
30.
Teresa Sadras Mickaël Martin Kohei Kume Mark E. Robinson Supraja Saravanakumar Gal Lenz Zhengshan Chen Joo Y. Song Tanya Siddiqi Laura Oksa Anne Marie Knapp Jevon Cutler Kadriye Nehir Cosgun Lars Klemm Veronika Ecker Janet Winchester Dana Ghergus Pauline Soulas-Sprauel Markus Müschen 《Molecular cell》2021,81(10):2094-2111.e9