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Philippe Brun Heykel Kchouk Brigitte Mouchet Véronique Baudouin Alain Raynaud Chantal Loirat Annabelle Azancot-Benisty 《Pediatric nephrology (Berlin, Germany)》1997,11(1):27-30
To evaluate the reliability of Doppler ultrasonography (US) in identifying children with renal artery stenosis (RAS) among
those with hypertension, we compared Doppler US results in 22 hypertensive children (mean age 8.9±4.3 years), with (13 cases)
and without RAS at angiography, and in 33 normotensive children (mean age 8.8±4.7 years). We observed 2 false-negatives and
2 false-positives with Doppler US. Of the 2 false-negative diagnoses, 1 had RAS on an accessory renal artery located behind
a normal upper polar artery and the other was observed in a patient with bilateral multiple stenosis of the very distal segments
of renal arteries. The 2 false-positive diagnoses were due to sinuous left renal artery and to technical reasons, respectively.
In another patient, Doppler US showed a tight RAS, while arteriography was normal. RAS was subsequently confirmed by a second
arteriography. Peak systolic velocity values of Doppler US were significantly higher in patients with proven angiographic
RAS (3.44±0.66 m/s) than in hypertensive patients with normal renal arteries at angiography (0.99±0.35 m/s, P <0.0001) and normotensive healthy children (1.04±0.23 m/s, P <0.0001). With the use of multiple views, and the experience acquired with practice, false-negatives or false-positives due
to the geometry of the renal artery can be avoided. Nevertheless, very distal stenosis can be missed by Doppler US.
Received October 30, 1995; received in revised form April 16, 1996; accepted May 14, 1996 相似文献
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Jean-Yves Baudouin Flavie Martin Guy Tiberghien Isabelle Verlut Nicolas Franck 《Neuropsychologia》2002,40(5):503-511
The selective attention to facial emotion and identity was investigated in 12 patients with schizophrenia and 12 healthy participants. Both patients and controls were required to perform two classification tasks (according either to identity or emotion). Two separate values for identity (person A/person B) and for emotion (fear/anger) were used. When the classification task was on one dimension, the other dimension was either correlated, constant, or orthogonal (Garner WR. The Processing of Information and Structure. Potomac, MD: Erlbaum, 1974, Garner WR. Interaction of stimulus dimensions in concept and choice processes. Cognitive Psychology 1976;8:98-123). Results indicated that both patients and healthy participants had an asymmetrical pattern of performance: they were able to selectively attend to the identity of the face presented, regardless of the emotion expressed on the face, but variation in identity interfered with the classification of facial emotion. Moreover, a correlational study indicated that the identity interference on emotion classification for schizophrenic patients covaried with the severity of their negative symptoms. The selective attention competencies in schizophrenia and the independence hypothesis of emotion and face recognition are discussed in the framework of current face recognition models. 相似文献
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P Darwin Bell Jean-Yves Lapointe 《Clinical and experimental pharmacology & physiology》1997,24(7):541-547
1. Macula densa (MD) cells are located within the thick ascending limb (TAL) and have their apical surface in contact with tubular fluid and their basilar region in contact with the glomerulus. These cells sense changes in luminal fluid sodium chloride concentration ([NaCl]) and transmit signals resulting in changes in vascular resistance (tubuloglomerular feedback) and renin release. 2. Current efforts have focused on understanding the cellular transport mechanisms of MD cells. Progress in this area has benefited from the use of the isolated perfused TAL-glomerular preparation, which permits direct access to MD cells. 3. Using microelectrodes to measure basolateral membrane potential (VBL) of MD cells, it was found that VBL was very sensitive to changes in luminal fluid [NaCl]. As [NaCl] was elevated from 20 to 150mmol/L, VBL was found to depolarize by over 30 mV. 4. Basolateral membrane potential measurements were also used to identify an apical Na+: 2CI?: K+ cotransport pathway in MD cells that is the major pathway for NaCl entry into these cells. 5. Other work identified a basolateral chloride channel that is presumed to be responsible for changes in VBL during alterations in luminal [NaCl]. This channel, which is the predominant conductance across the basolateral membrane, may be regulated by intracellular Ca2+ and cAMP. 6. An apical Na+: H+ exchanger in MD cells was detected by measuring changes in intracellular pH using the fluorescent probe 2′,7′-bis-(2-carboxyethyl)-5(and-6) carboxyfluorescein. 7. Using patch-clamp techniques, a high density of pH- and Ca2+-sensitive K+ channels was observed at the apical membrane of MD cells. 8. Other studies found that, at the normal physiological conditions prevailing at the end of the TAL (luminal [NaCl] of 20–60 mmol/L), reabsorption mediated by MD cells is very sensitive to changes in luminal [NaCl]. 相似文献
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le Cotonnec Jean-Yves; Porchet Herve C.; Beltrami Vanya; Howles Colin 《Human reproduction (Oxford, England)》1993,8(10):1604-1611
These studies were designed to compare the pharmacokinetic characteristicsof a very highly purified urinary human follicle stimulatinghormone (FSH-HP) preparation (sp. act. 9000 IU FSH/mg of protein),Metrodin HP®, with a standard urinary FSH preparation Metrodin®(FSH). The two preparations were administered in a balanced,random-order, cross-over sequence as single doses of 150IU,separated by 1 week of washout to 12 female volunteers by i.v.injection and to 12 male volunteers by i.m. and s.c. routes.FSH concentrations were measured by immunoradiometric assayand by an in-vitro rat granulosa cell aromatase bioassay. Afteran i.v. bolus, the pharmacokinetics of the two FSH preparationswere identical. Total clearance was 0.5 and 0.15 1/h respectivelyfor immunoassay and bioassay data. Immunoassay showed that thetwo preparations were similar for renal clearance (0.1 1/h),volumes of distribution at steady state (9 1), distributionand terminal half-lives (2 and 17 h, respectively). After parenteraladministrations, the absorption half-life of FSH was 3 h andthe apparent terminal half-life was 1.5 days. Both preparationshad relative bio-availabilities close to 100% for i.m. and s.c.administrations. Immunopurification, which results in a veryhighly purified FSH-HP, does not modify the pharmacokineticproperties of FSH. This study also confirmed that s.c. and i.m.doses of FSH-HP are equivalent from the pharmacokinetic andpharmacodynamic points of view. 相似文献
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Fawzia Zeraria Olivier Dry Jacqueline Fischer Yveline Frobert Jean-Yves Couraud Marie Conrath 《Journal of chemical neuroanatomy》1995,9(1):65-77
A monoclonal antibody directed against a peptide (PS5) specified by RNA complementary to the mRNA coding for substance P (SP), was used to label SP receptors in the rat spinal cord as demonstrated by light and electron microscopy. An immunocytochemical method (avidin-biotin-peroxidase) was used on vibratome sections from rats perfused with paraformaldehyde. Immunoreactivity was observed principally in the two superficial layers of the dorsal horn, in lamina X and the region of motoneurons. The labeling was absent when the antibody was preincubated with the complementary peptide (PS5) used as immunogen. Competition between the anti-complementary peptide antibody and different ligands was tested by preincubation of tissue sections with the ligand in the presence of peptidase inhibitors before addition of the antibody. A specific agonist (SP) or antagonist (spantide, RP 67580) at 10−6M led to total absence of labeling. These results indicate that under our experimental conditions, the anti-complementary peptide antibody recognizes a SP binding site in the rat spinal cord. Electron microscopic study of the two superficial laminae of the dorsal horn showed that immunolabeling was mainly localized extracellularly at apposing neuronal plasma membranes. It was mostly associated with axodendritic or axosomatic appositions. Occasionally labeling was observed between two axon terminals. In all cases, these appositions were non junctional. Generally, neuronal processes involved in these appositions did not contain large granular vesicles. These observations suggest that SP may act in a diffuse, nonsynaptic manner probably on targets distant from SP release sites. 相似文献
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