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P. Ferrandon B. Barcelo JC Perche and AR Schoffs 《Fundamental & clinical pharmacology》1994,8(5):446-452
Summary— The suggestion that adenosine may have beneficial effects on post reperfusion survival following cardiac ischaemia has led to the search for agents which increase the concentration of this substance in the ischemic region as a possible therapeutic approach to the treatment of angina and myocardial infarction. In the present study, dipyridamole, soluflazine and lidoflazine, known inhibitors of the nucleotide exchange system, have been shown using an HPLC method to prevent the decrease in the concentration od added adenosine outside human red blood cells in vitro. However, the results suggest that this effect was due to inhibition of adenosine deaminase rather than inhibition of nucleotide exchange as had previously been suggested. The selective inhibitor of adenosine deaminase erythro-9-(2 hydroxy-3-nonyl adenosine) exhibited the same profile of activity in the human red blood cell assay. pIC50 values for the four compounds named above were found to be 6.80 ± 0.09, 6.95 ± .03, 6.10 ± 0.14 and 7.39 ± 0.05 vs adenosine disapearance observed in the extracellular incubation medium respectively. Thus, as the disappearance of adenosine outside the cells was not due to its uptake but to its catabolism, this in vitro method does not appear to be predictive for the ability of compounds to act on adenosine uptake into cardiac myocytes. Any antiischemic action of these agents is more readily explained by an inhibition of the catabolism of adenosine and not by the inhibition of its transport across the membrane of cardiac myocytes. 相似文献
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Cerebral microgyria, thalamic cell size and auditory temporal processing in male and female rats 总被引:4,自引:2,他引:2
Herman AE; Galaburda AM; Fitch RH; Carter AR; Rosen GD 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(5):453-464
Induction of microgyria by freezing injury to the developing somatosensory
cortex of neonatal rats causes a defect in fast auditory processing in
males, but not in females. It was speculated that early damage to the
cortex has sexually dimorphic cascading effects on other brain regions
mediating auditory processing, which can lead to the observed behavioral
deficits. In the current series of experiments, bilateral microgyri were
induced by placement of a freezing probe on the skulls of newborn male and
female rats, and these animals were tested in adulthood for auditory
temporal processing. Control animals received sham surgery. The brains from
these animals were embedded in celloidin, cut in the coronal plane and the
following morphometric measures assessed: microgyric volume, medial
geniculate nucleus (MGN) volume, cell number, and cell size, and, as a
control, dorsal lateral geniculate nucleus (dLGN) volume, cell number and
cell size. There were no sex differences in the cortical pathology of
lesioned animals. However, microgyric males had more small and fewer large
neurons in the MGN than their sham-operated counterparts, whereas there was
no difference between lesioned and sham-operated females. There was no
effect on dLGN cell size distribution in either sex. Microgyric males were
significantly impaired in fast auditory temporal processing when compared
to control males, whereas lesioned females exhibited no behavioral
deficits. These results suggest that early injury to the cerebral cortex
may have different effects on specific thalamic nuclei in males and
females, with corresponding differences in behavioral effects.
相似文献
107.
MUSTAFA B HOSCAN ALIM KOAR ÜMT GÜMÜTA MEHMET GÜNEY 《International journal of urology》2006,13(3):301-302
Spontaneous migration of an intrauterine device into the bladder is very rare. A 29-year-old woman in whom an intrauterine device had been placed 6 years previously, presented complaining of chronic pelvic pain and recurrent irritative urinary tract symptoms. One year after insertion she had became pregnant and given birth without complications. Intravesical migration of the intrauterine device was confirmed by sonography and cystoscopy. The intrauterine device was removed by suprapubic cystostomy. 相似文献
108.
G D''Andrea AR Cananzi R Joseph M Morra F Zamberlan F Ferro Milone S Grunfeld KMA Welch 《Cephalalgia : an international journal of headache》1991,11(4):197-200
Platelet levels of glutamic and aspartic acid and glycine were measured in patients with migraine with aura, migraine without aura, tension headache and cluster headache. High levels of these amino acids were found in patients with migraine with aura compared to normal subjects and other headache groups. During headache, glutamate levels further increased in migraine with aura patients. These findings may have relevance to the neurological symptoms of migraine with aura. 相似文献
109.
Recombinant human granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood stem/progenitor cells (PBPC) have replaced bone marrow (BM) harvests for autologous transplantation after myeloablative therapy in cancer patients. G-CSF-mobilized PBPC from healthy donors contain one log excess of T lymphocytes representing a potential risk for graft-versus-host disease (GVHD). However, recent pilot clinical studies of G-CSF-mobilized allogeneic PBPC transplantation have shown rapid haematological recovery and no severe acute GVHD except in a very few cases. Therefore, the risk of inducing severe acute GVHD is not as high as was expected during the pioneering period of allogeneic PBPC transplantation.The present study was performed to address the possible reasons for the rapid haematological recovery and the absence of severe acute GVHD observed after allogeneic PBPC transplantation by comparing the contents and subsets of CD3+ and CD34+ G-CSF-mobilized PBPC (n = 31) with those of BM (n = 26) allografts from healthy adult donors. The present results revealed that the phenotypic profiles of CD3+ and CD34+ cells differ between PBPC and BM allografts. The single PBPC leukapheresis product contained 10 times more mononuclear cells, 1.5 times more CD34+ cells, 5.5 times more CD3+ T lymphocytes, 3 times more CD19+ B lymphocytes and 3.8 times more CD14+ monocytes than the single BM harvest. Both CD34+CD33+ myeloid progenitor cells and CD34+HLA-DR- long-term reconstituting haemopoietic stem cells were significantly increased in the CD34+ G-CSF-mobilized PBPC compared with the CD34+ BM cells; median 73.1% and 30.4% vs 60.6% and 5.0%, respectively, P < 0.01.The percentage of CD3+ cells coexpressing CD4 (T helper/inducer) was similar in both PBPC and BM allografts, 47.2% and 45.6%, respectively, whereas the percentage of CD3+ cells coexpressing CD8 (T suppressor/cytotoxic) was significantly decreased in PBPC compared with BM; 37.0% vs 55.9%, p < 0.01. 相似文献
110.