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21.
The interaction of parafluorohexahydrosiladiphenidol at muscarinic receptors in vitro 总被引:6,自引:6,他引:0 下载免费PDF全文
R M Eglen A D Michel W W Montgomery E A Kunysz C A Machado R L Whiting 《British journal of pharmacology》1990,99(4):637-642
1. The antagonistic actions of parafluorohexahydrosiladiphenidol (pFHHSiD) at muscarinic receptors has been studied in cardiac muscle, smooth muscle and cell culture preparations. In this paper, the classification scheme of Doods et al. (1987) is employed. This scheme is based upon differential affinities of muscarinic antagonists. pFHHSiD exhibited high pA2 values at M3 receptors mediating contractions of guinea-pig ileum and oesophageal muscularis mucosae (7.8 and 8.2 respectively) whereas low values were determined at M2 receptors mediating negative inotropic responses in guinea-pig atria (6.0). Intermediate pA2 values were determined at M1 receptors mediating contractions of the canine femoral and saphenous veins. 2. The pA2 values of pFHHSiD at receptors mediating endothelial-dependent relaxation of rat aortic rings, rabbit jugular vein and canine femoral artery (7.6-7.9) were similar to those determined on the ileum. However, the pA2 values of pFHHSiD at receptors mediating contractions of the guinea-pig trachea (7.1), which has been previously shown to possess M3 receptors, were different from those determined in the ileum. 3. The similarity in pA2 values of pFHHSiD between the M3 receptors in guinea-pig ileum and the receptors mediating endothelial-dependent relaxations provide further evidence for the role of M3 receptors in this vascular response. Taken together, pA2 values for pFHHSiD range from 7.1 to 8.2, depending upon the M3 preparation used. The selectivity of the compound therefore for the M3 versus the M2 muscarinic receptor ranged from 13 to 163 fold.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
22.
Nadia Sdiqui Khalil Arar Patrick Midoux Roger Mayer Michel Monsigny Annie-Claude Roche 《Drug delivery》1995,2(1):63-72
The Ha-ras oncogene promotes cell proliferation. Antisense oligonucleotides complementary to the ras gene sequence encompassing a mutated codon 12 selectively induce a cell proliferation inhibition. However, the concentration required to reach an effective inhibition is high due to the low efficiency of the oligonucleotide crossing through cell membranes, leading to a low concentration in the cytosol and/or the nucleoplasm. In the present paper, we show that anti-ras oligonucleotides linked to a glycosylated carrier, serum albumin bearing mannose 6-phosphate residues, are more efficient than free oligonucleotides or oligonucleotides bound to an unglycosylated carrier at inhibiting proliferation of a human tumor mammary cell line expressing the mutated Ha-ras. Using fluorescein-labeled neoglycoproteins and fluorescein-labeled oligonucleotides bound to neoglycoproteins, flow cytometry and confocal microscopy revealed that (i) these tumor cells express a membrane lectin specific for mannose 6-phosphate-bearing proteins, (ii) the membrane lectin actively mediates the uptake of macromolecules substituted with mannose 6-phosphate, and (iii) the fluorescein-labeled oligonucleotides bound to the neoglycoprotein accumulate in intracellular vesicles. Furthermore, with antisense oligonucleotides carried by the neoglycoproteins, the concentration required to inhibit cell proliferation is lower than that of the carrier-free antisense oligonucleotides. 相似文献
23.
Laparoscopic hysterectomy 总被引:1,自引:0,他引:1
Michel Canis Gerard Mage Charles Chapron Arnaud Wattiez Jean Luc Pouly Maurice Antoine Bruhat 《Surgical endoscopy》1993,7(1):42-45
Summary Thirty-three patients were selected for laparoscopic hysterectomy and operated on in the Department of Obstetrics, Gynecology and Reproductive Medicine of Clermont-Ferrand University Hospital. Surgical techniques included blunt dissection with scissors and bipolar coagulation to achieve hemostasis. A case was considered successful when all the uterine vessels were treated by laparoscopy. Twenty-four cases were completed laparoscopically (72.7%). None of these patients had postoperative bleeding; 22 had an uneventful postoperative recovery. Nine procedures were converted to laparotomy (27.3%), five because of a difficult or unsatisfactory hemostasis. We conclude that in selected cases, a total hysterectomy can be performed safely by experienced laparoscopists. Further technological progress is necessary to make this procedure more acceptable. Its value as compared to the others will have to be demonstrated. 相似文献
24.
Nonadrenergic [3H]idazoxan binding sites are physically distinct from alpha 2-adrenergic receptors 总被引:4,自引:0,他引:4
M C Michel J W Regan M A Gerhardt R R Neubig P A Insel H J Motulsky 《Molecular pharmacology》1990,37(1):65-68
We have recently demonstrated that the alpha 2-adrenergic radioligand [3H]idazoxan also labels additional sites that do not recognize catecholamines but bind with high affinity several chemically distinct drugs previously assumed to be highly selective for alpha 2-adrenergic receptors [Mol. Pharmacol. 35:324-330 (1989)]. We now have used three approaches to distinguish the nonadrenergic [3H]idazoxan sites from alpha 2-adrenergic receptors. (a) No nonadrenergic [3H]idazoxan binding sites were found in COS-7 cells transfected with the genes for the two known alpha 2-adrenergic receptor subtypes. (b) The ratio of alpha 2-adrenergic and nonadrenergic [3H]idazoxan sites in human platelet membranes varied considerably between various donors. (c) Highly purified platelet plasma membranes were enriched for alpha 2-adrenergic receptors but did not contain any nonadrenergic [3H]idazoxan binding sites. We conclude that the nonadrenergic [3H]idazoxan binding sites are not co-expressed with alpha 2-adrenergic receptors and at least in human platelets may be located in an intracellular compartment. 相似文献
25.
Michel Rostin Philippe Barthe Georges Houin Michel Alvinerie François Bouissou 《Pediatric nephrology (Berlin, Germany)》1990,4(5):470-473
The aim of this study was to establish whether the criteria for the clinical effectiveness of steroids are correlated with the pharmacokinetics of prednisolone in children treated with prednisone during an attack of idiopathic nephrotic syndrome (INS). Thirteen patients with nephrosis were included. Prednisolone, prednisone and cortisol levels were measured using a specific high-performance liquid chromatography assay after an oral dose of 1 mg/kg body weight of prednisone taken at the onset of the disease. All the pharmacokinetic parameters, including the conversion of prednisone to prednisolone were similar to the data already published in children with INS. No correlation was found between the values of pharmacokinetic parameters and criteria of clinical effectiveness. Hypo-albuminaemia was significantly correlated with the area under the plasma-concentration curve but not with the elimination half-life of prednisolone. Moreover, the prednisolone elimination half-life correlated with the urinary exretion of 17-hydroxycorticosteroids achieved in the first 6h. The present study suggests that routine measurements of prednisolone kinetics do not help when assessing the treatment of children with INS. 相似文献
26.
Gérald Vanzetto Marc Janier Daniel Fagret Luc Cinotti Xavier André-Fouet Michel Comet Jacques Machecourt 《European journal of nuclear medicine and molecular imaging》1997,24(2):170-178
The best test presently available to ascertain residual viability within an infarct-related area involves the use of fluorine-18
fluorodeoxyglucose (FDG) to detect the persistence of some cellular metabolism. Rest reinjection of thallium-201 is a less
accurate alternative but is easy to perform. Iodinated fatty acids, which are used with standard gamma cameras, are proposed
as markers of cellular metabolism. This study was performed to assess the value of 16-iodo-3-methyl-hexadecanoic acid (MIHA)
as a marker of the residual cellular metabolism by comparison with FDG in patients with a recent myocardial infarction, and
to evaluate its contribution compared with the201Tl stress-redistribution-reinjection technique. Stress-redistribution-reinjection201T1 imaging, rest MIHA imaging and glucoseloaded FDG imaging were performed in 22 patients with recent myocardial infarction.
Out of the 628 myocardial segments obtained from the left ventricular analysis, 400 were hypoperfused (relative uptake <0.75
of maximum uptake on stress201T1 imaging), 177 of which were severely hypoperfused (relative uptake <0.50). Receiver operating characteristic (ROC) curves
for predicting metabolic myocardial viability with FDG were derived from the results in respect of (a)201T1 activity during exercise, redistribution and reinjection and (b) MIHA up-take, using the two FDG thresholds most commonly
considered to define metabolic viability (0.50 and 0.60). Analysis of the 400 hypoperfused segments demonstrated that201T1 reinjection was the most accurate test in predicting the presence of myocardial viability (area under the ROI curves=0.85
and 0.86 at the 0.50 and 0.60 FDG thresholds, respectively;P<0.05 vs other tests). The global predictive values of MIHA and201T1 reinjection were, respectively, 0.87 and 0.89 at the 0.50 FDG threshold (NS), and 0.82 and 0.87 at the 0.60 FDG threshold
(NS). When only the 177 severely hypoperfused segments were considered,201T1 reinjection remained the most accurate test (accuracy 0.84 at the 0.50 FDG threshold and 0.82 at the 0.60 FDG threshold),
while the accuracy of MIHA decreased significantly (0.78 at the 0.50 FDG threshold and 0.73 at the 0.60 FDG threshold,P<0.05 vs201T1 reinjection). In all circumstances, MIHA was less specific than201T1 reinjection for the detection of metabolic viability. In conclusion, in patients with recent myocardial infarction, MIHA
accurately detects the persistence of metabolic viability, but is not superior to201T1. 相似文献
27.
Farsin Hamzei Michel Rijntjes Joystone Gbadamosi Kornelius Fuchs Cornelius Weiller Alexander Münchau 《Movement disorders》2003,18(8):959-961
We report on a woman with a an 8-year history of multiple system atrophy with predominance of parkinsonism who developed jaw-locking oromandibular dystonia within hours after insertion of ill-fitting dentures. Dystonia spread rapidly to involve other facial muscles and the larynx causing stridor with respiratory failure necessitating crush intubation. 相似文献
28.
Michel Broyer Geneviève Guest Marie-France Gagnadoux Daniel Beurton 《Pediatric nephrology (Berlin, Germany)》1987,1(1):16-21
The files of 334 consecutive cadaver kidney (CK) and of 27 living related (LR) transplantations (T) in children and adolescents performed from 1973 to 1984 have been reviewed. Following cadaver transplantation, 52 patients (15%) never had hypertension (HT), 41 patients (12%) had only initial HT up to 6 months after transplantation and 18 other patients (5%) exhibited transient HT episodes while on high-dose steroid therapy. Finally, 209 patients (62%) had HT for periods longer than 6 months and 16 patients (5%) until death or graft failure within the first 3 months. Chronic graft rejection was the major cause of HT, but other factors either isolated or in association were also present. Renal artery stenosis (RAS) was diagnosed in 43 cases (13%) 2–17 months post-transplantation; 10 of these were operated upon (5 successfully) and 9 underwent transluminal angioplasty with a single success. Nine cases of RAS resolved spontaneously. HT was attributed to the host kidney in 10 cases (3%) and to recurrence of primary renal disease in 9 (3%). HT observed after CKT was sometimes severe and difficult to control. Acute complications from HT were recorded in 35 cases, with 6 deaths and 2 severe neurological sequelae. Among 25 LRT, 11 cases (40%) had no HT 13 (48%) had HT for longer than 6 months. In this group, no case of RAS was observed and only one complication (without sequelae) was noted. In conclusion, HT is a frequent and sometimes severe complication post-transplantation in children and adolescents. 相似文献
29.
I Mercanti F Michel L Thomachot D-A Loundou C Nicaise R Vialet J-N Di Marco P Lagier C Martin 《Archives de pédiatrie》2007,14(7):875-880
Transcutaneous bilirubinometry is an effective screening tool for neonatal jaundice in full-term babies. But its accuracy is not shown yet in preterm infants. METHODOLOGY: We carried out a prospective study in a neonatal intensive care unit. The study included 47 preterm infants. From birth, a transcutaneous bilirubin measurement (BTc) using the BiliCheck was made on the forehead of each newborn every 8 h. Blood sampling for determination of total serum bilirubin (BS) was combined with BTc: 1) if value of BTc was higher than limits values for phototherapy; 2) on the second day of life and 3) 4 hours after cessation of phototherapy. RESULTS: Mean gestational age was 30 week and mean birth weight was 1419 g. We studied 151 pairs of BTc and BS. Mean values obtained by BTc and BS were respectively 160.6+/-50 mumol/L and 190.6+/-61.4 mumol/L. A significant correlation between BTc and BS was found. But the limits of agreement were very wide. The negative predictive value (NPV) of BTc was above 90% in each group of gestational age. DISCUSSION: The need for phototherapy cannot be determined by BTc in preterm infants. But the BTc is reliable when its value is under the limits for phototherapy. CONCLUSION: With a very high incidence of neonatal jaundice (87%) in our cohort, a value of BTc under the limits for phototherapy has a good NPV in preterm infants. 相似文献
30.