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101.
Platelet monoamine oxidase activity in Down's syndrome 总被引:1,自引:0,他引:1
Christopher J. Fowler Åsa Wiberg Karl-Henrik Gustavson Bengt Winblad 《Clinical genetics》1981,19(5):307-311
The activity of platelet monoamine oxidase in Down's syndrome cases was significantly lower than that of controls. This difference was found for both males and females, and with tyramine, tryptamine and β-phenethylamine as substrate. The Km values of the monoamine oxidase towards tryptamine as substrate from controls and Down's syndrome patients were similar. 相似文献
102.
L Hillered L Persson H G Bolander A Hallstr?m U Ungerstedt 《Neuroscience letters》1988,95(1-3):286-290
Extracellular (EC) ascorbate concentrations were measured in microdialysates from the striatum bilaterally in rats subjected to unilateral middle cerebral artery occlusion (MCAO). The focal cerebral ischemia induced a dramatic increase in ascorbate on the ipsilateral (operated) side while the levels remained at the preocclusion level in the striatum of the contralateral (control) hemisphere. The possibility that ascorbate may aggravate ischemic neuronal damage by its proposed neuromodulatory properties and/or by its ability to induce lipid peroxidation is discussed. 相似文献
103.
Larsson J Persson C Tengvall P Lundqvist-Gustafsson H 《Journal of biomedical materials research. Part A》2004,68(3):448-457
Polymorphonuclear neutrophils (PMN) are among the first inflammatory cells to arrive at an implant interface, where they encounter with the foreign material and may produce reactive oxygen species (ROS). During the interaction between titanium and ROS, titanium-peroxy (Ti-peroxy) compounds may be formed. We used a Ti-peroxy gel, made from titanium and hydrogen peroxide, to study the effects of Ti-peroxy compounds on PMN. In the absence of serum, the Ti-peroxy gel decreased the oxidative response of PMN to yeast and PMA and reduced PMN apoptosis without inducing necrosis. These effects could not be ascribed to the release of hydrogen peroxide from the Ti-peroxy gel, because a steady-state hydrogen peroxide producing system failed to mimic the effects of the gel. The effects were similarly unaffected when PMN were preincubated with beta(2)-integrin antibodies, questioning the involvement of adhesion molecules. Nevertheless, when a filter was used to separate the Ti-peroxy gel from the cells, the gel effect on PMN life span was abolished, pointing to a contact-dependent mechanism. In the presence of serum, the Ti-peroxy gel had no effect on the PMN oxidative response and life span, but appeared rather inert. In summary, this study demonstrates that the Ti-peroxy gel has potentially anti-inflammatory properties through a combined peroxide and physical contact effect, supporting the notion that interactions between titanium and inflammatory cells are responsible for the good performance of titanium in vivo. 相似文献
104.
Molecular epidemiology of hospital-associated and community-acquired Clostridium difficile infection in a Swedish county
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Norén T Akerlund T Bäck E Sjöberg L Persson I Alriksson I Burman LG 《Journal of clinical microbiology》2004,42(8):3635-3643
All episodes of Clostridium difficile associated diarrhea (CDAD) diagnosed in a defined population of 274,000 including one tertiary and two primary hospitals and their catchment areas were studied during 12 months. The annual CDAD incidence in the county was 97 primary episodes per 100,000, and 78% of all episodes were classified as hospital associated with a mean incidence of 5.3 (range, 1.4 to 6.5) primary episodes per 1,000 admissions. The incidence among hospitalized individuals was 1,300-fold higher than that in the community (33,700 versus 25 primary episodes per 100,000 persons per year), reflecting a 37-fold difference in antibiotic consumption (477 versus 13 defined daily doses [DDD]/1,000 persons/day) and other risk factors. Three tertiary hospital wards with the highest incidence (13 to 36 per 1,000) had CDAD patients of high age (median age of 80 years versus 70 years for other wards, P < 0.001), long hospital stay (up to 25 days versus 4 days), or a high antibiotic consumption rate (up to 2,427 versus 421 DDD/1,000 bed days). PCR ribotyping of C. difficile isolates available from 330 of 372 CDAD episodes indicated nosocomial acquisition of the strain in 17 to 27% of hospital-associated cases, depending on the time interval between index and secondary cases allowed (2 months or up to 12 months), and only 10% of recurrences were due to a new strain of C. difficile (apparent reinfection). In other words, most primary and recurring episodes were apparently caused by the patient's endogenous strain rather than by one of hospital origin. Typing also indicated that a majority of C. difficile strains belonged to international serotypes, and the distribution of types was similar within and outside hospitals and in primary and relapsing CDAD. However, type SE17 was an exception, comprising 22% of hospital isolates compared to 6% of community isolates (P = 0.008) and causing many minor clusters and a silent nosocomial outbreak including 36 to 44% of the CDAD episodes in the three high-incidence wards. 相似文献
105.
Comparison of mismatch amplification mutation assay with DNA sequencing for characterization of fluoroquinolone resistance in Neisseria gonorrhoeae 总被引:3,自引:0,他引:3
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Sultan Z Nahar S Wretlind B Lindback E Rahman M 《Journal of clinical microbiology》2004,42(2):591-594
A mismatch amplification mutation assay (MAMA) was developed for identification of point mutations in quinolone resistance-determining region (QRDR) of gyrA at codons 91 and 95. MAMA PCR was used to detect mutations at codons 91 and 95 of gyrA in 117 Neisseria gonorrhoeae isolates (with ciprofloxacin MICs of 0.004 to >32 microg/ml) from Bangladesh during 1997 to 2001. The QRDR regions of the gyrA genes from 31 randomly selected isolates were sequenced, and the results were compared with those of MAMA PCR. Using mismatch PCR, a mutation at Ser91 could be detected in all 27 (resistant and intermediate) isolates, and an Asp95-to-Gly95 mutation could be detected in all 15 isolates, as detected by sequencing. MAMA PCR offers a simple, inexpensive, rapid, and easier alternative for detection of point mutations in fluoroquinolone resistance in N. gonorrhoeae. 相似文献
106.
107.
108.
During hypoxic exercise some vasoconstriction is needed to match O2 delivery with O2 demand at the microcirculatory level. 总被引:1,自引:0,他引:1
Carsten Lundby Robert Boushel Paul Robach Kirsten M?ller Bengt Saltin José A L Calbet 《The Journal of physiology》2008,586(1):123-130
To test the hypothesis that the increased sympathetic tonus elicited by chronic hypoxia is needed to match O(2) delivery with O(2) demand at the microvascular level eight male subjects were investigated at 4559 m altitude during maximal exercise with and without infusion of ATP (80 mug (kg body mass)(-1) min(-1)) into the right femoral artery. Compared to sea level peak leg vascular conductance was reduced by 39% at altitude. However, the infusion of ATP at altitude did not alter femoral vein blood flow (7.6 +/- 1.0 versus 7.9 +/- 1.0 l min(-1)) and femoral arterial oxygen delivery (1.2 +/- 0.2 versus 1.3 +/- 0.2 l min(-1); control and ATP, respectively). Despite the fact that with ATP mean arterial blood pressure decreased (106.9 +/- 14.2 versus 83.3 +/- 16.0 mmHg, P < 0.05), peak cardiac output remained unchanged. Arterial oxygen extraction fraction was reduced from 85.9 +/- 5.3 to 72.0 +/- 10.2% (P < 0.05), and the corresponding venous O(2) content was increased from 25.5 +/- 10.0 to 46.3 +/- 18.5 ml l(-1) (control and ATP, respectively, P < 0.05). With ATP, leg arterial-venous O(2) difference was decreased (P < 0.05) from 139.3 +/- 9.0 to 116.9 +/- 8.4(-1) and leg .VO(2max) was 20% lower compared to the control trial (1.1 +/- 0.2 versus 0.9 +/- 0.1 l min(-1)) (P = 0.069). In summary, at altitude, some degree of vasoconstriction is needed to match O(2) delivery with O(2) demand. Peak cardiac output at altitude is not limited by excessive mean arterial pressure. Exercising leg .VO(2peak) is not limited by restricted vasodilatation in the altitude-acclimatized human. 相似文献
109.
The influence of HLA-A, B-matching on the results of 362 cadaver renal transplantations was analyzed. Of these, 34 of the patients had diabetes and 105 were 55 years old or more. The case material was divided into groups, based on the number of HLA-A, B incompatibilities. The occurence of factors having a possible bearing on kidney graft survival was determined in each match group. It was found that several of these factors, such as the immunosuppressive agents given and the number of high-risk patients, were unequally distributed in the various groups. This may be related to changes in policy that have occured since the transplant unit was moved to Huddinge Hospital in November 1973. In order to obtain homogeneous case material, the Huddinge series was analyzed separately.
A significant difference in survival was found in both materials between transplants with 2 or less incompatibilities and those with more than 2 incompatibilities. A significant difference in patient survival between these two groups was found in the total case material. 相似文献
A significant difference in survival was found in both materials between transplants with 2 or less incompatibilities and those with more than 2 incompatibilities. A significant difference in patient survival between these two groups was found in the total case material. 相似文献
110.
Two test-kits — API and Oxi Ferm tube — have been compared for accuracy in individual tests and for identification on the genus or species level with conventional biochemical tests on 154 oxidative-fermentative gram-negative rods. The two test systems were found to be reliable and permit identification of the clinically most significant oxidative-fermentative strains. 相似文献