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991.
992.
The kinin B1 receptor antagonist des-Arg9-[Leu8]bradykinin: an antagonist of the angiotensin AT1 receptor which also binds to the AT2 receptor.
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D Pruneau A Duvoid J M Luccarini P Bélichard J C Bonnafous 《British journal of pharmacology》1995,114(1):115-118
1. Agonists and antagonists of kinin B1 and B2 receptors were evaluated in vitro for their effects against angiotensin II (AII)-induced contractile responses in the rabbit aorta and for their binding properties to angiotensin AT1 and AT2 receptors from purified membrane of rat liver and lamb uterus respectively. 2. In aortic rings, the kinin B1 receptor antagonist, des-Arg9-[Leu8]bradykinin (BK) (3-100 microM) caused a concentration-dependent decrease in sensitivity and a depression of the maximum response to AII. Des-Arg10-[Leu9]kallidin (KD), des-Arg9-BK, des-Arg10-KD, BK or KD at 3 microM had no effect against AII-induced contractions. 3. Des-Arg9-[Leu8]BK (3 or 100 microM) did not affect contractions of aortic rings to histamine, potassium chloride, endothelin-1, 5-hydroxytryptamine, noradrenaline and the thromboxane A2-mimetic, U46619. 4. Des-Arg9-[Leu8]BK displaced [125I]-Sar1-AII binding to the AT1 subtype in rat liver membranes with a Ki value of 1.1 +/- 0.4 microM. Values of Ki for des-Arg9-BK and KD were 45 +/- 13 microM and 25 +/- 22 microM, respectively. The other kinin derivatives des-Arg10-KD, BK and des-Arg10-[Leu9]KD at concentrations up to 100 microM did not bind to the AT1 receptor. 5. All the kinin derivatives except BK bound to AT2 receptors in lamb uterus membranes. Values of Ki for des-Arg9-[Leu8]BK, des-Arg10-[Leu9]KD, des-Arg9-BK, des-Arg10-KD and KD were 0.3 +/- 0.1, 0.7 +/- 0.1, 1.2 +/- 0.3, 1.5 +/- 0.3 and 7.0 +/- 1.6 microM, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
993.
The major benefit of antenatal ultrasonography is to allow early diagnosis of urinary tract malformations before postnatal infection worsens the prognosis. In the majority of cases, there is a unilateral and moderate dilatation requiring a check-up only during the second week of life; treatment subsequently depends on the etiology of the uropathy and the consequences on the kidney. Unilateral severe dilatations and bilateral, but moderate, dilatations must be managed immediately after birth in a pediatric surgical center. In the rare cases of severe bilateral obstructive uropathy, in utero decompression by catheterisation or surgery is now considered to be uselessly invasive, considering that renal dysplasia is already present when the malformation is detected. 相似文献
994.
Distribution of Hepatitis B Virus Genotypes in Two Different Pediatric Populations from Argentina 总被引:12,自引:2,他引:10
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V. A. Mbayed J. L. Lpez P. F. S. Telenta G. Palacios I. Badía A. Ferro C. Galoppo R. Campos 《Journal of clinical microbiology》1998,36(11):3362-3365
Differences in pathogenesis and the probability of becoming a chronic carrier depend on the age at which hepatitis B virus (HBV) infection is acquired, ranging from 82% in infants less than 6 months of age to 15 to 30% in older children. HBV genotypes from 22 pediatric patients from two areas that differ in prevalence have been determined. Phylogenetic analysis shows a clear difference between the genotype distribution in Buenos Aires, a low-prevalence area, and that found in Gualeguay, Entre Ríos, a high-prevalence area. While the analysis allocated the sequences in the Buenos Aires group to genotypes A (36%), D (9%), and F (55%), the Gualeguay group presented exclusively genotype A isolates with very low nucleotide divergence, which suggests a strong founder viral population. The high prevalence of genotype F in the Buenos Aires group and its high intragroup heterogeneity agree with the American origin of this genotype. 相似文献
995.
I A Cotgreave P Moldéus R Brattsand A Hallberg C M Andersson L Engman 《Biochemical pharmacology》1992,43(4):793-802
Here we describe a new class of organoselenium compounds possessing glutathione peroxidase-like activity. The parent compound, alpha-(phenylselenenyl)acetophenone (PSAP), increased the rate of reaction of glutathione with H2O2, tert-butylhydroperoxide, cumene hydroperoxide, linoleic acid hydroperoxide and dilinoleyl lecithin hydroperoxide by 7.0, 25.1, 34.1, 19.1 and 8.4-fold, respectively, as assessed by the oxidized glutathione (GSSG) reductase enzyme assay. Direct assay of the removal of hydrogen peroxide and glutathione from reaction mixtures confirmed the peroxidase-like activities of these selenoorganic compounds, but indicate that the conventional coupled GSSG reductase assay may be unsuitable for the assessment of the catalytic capacity of PSAP and Ebselen. One possible mechanism of catalysis by PSAP involves an initial oxidation at selenium. Thiol may then react with the selenoxide to yield a selenium (II) compound, H2O and a disulfide. Compounds derived from PSAP may provide potential selenium-based anti-inflammatory agents. 相似文献
996.
Thirty-four patients having chronic idiopathic headaches participated in a long-term study comparing autogenic relaxation training alone (REL) with combinations of relaxation and electromyographic biofeedback (REL + EMG) or relaxation and temperature biofeedback (REL + TEMP). Assignment to treatment conditions was balanced on demographics and clinical characteristics, as well as headache classification according to muscle contraction or vascular headache symptomatology. The results indicate that REL + TEMP produced no additional improvements over REL following the 8-week treatment program, or at 6-month, or 12-month follow-up. However, REL + EMG produced significantly greater reductions in headache activity measures than the REL and REL + TEMP conditions at all post-treatment time points. Headache activity continued to improve over the follow-up period independent of treatment condition. These data indicate that EMG biofeedback augments long-term clinical improvements in headache patients who undergo autogenic relaxation training. 相似文献
997.
F. J. Jimnez-Jimnez P.J. García-Ruiz J. Garci de Ybenes A. Vzquez D. García Urra B. Morales E. Varela de Seijas 《European journal of neurology》1997,4(5):498-501
Calcium channel blockers can act on dopaminergic systems, and some reports suggest that they could be useful for the treatment of several movement disorders. In order to assess the efficacy of nicardipine in tics disorders we performed a prospective open non-controlled study which included 10 previously untreated patients. Our results suggest that nicardipine could be a useful and safe treatment for tics. 相似文献
998.
Previous studies examining the association between social comparison processes and body image dissatisfaction have yielded inconsistent findings. This study examined whether such discrepancies are due to either the use of identical comparison targets for all subjects or variability in body mass. Specifically, 216 subjects were randomly assigned to one of three experimental conditions: self-generated upward comparison group, self-generated downward comparison group, or control group. Dependent variables were measures of body image. Results indicated that increasing body mass and trait comparison tendencies were associated with increased body dissatisfaction. However, the experimental manipulation did not affect body image ratings. Results suggest that social comparison processes may operate similarly over a range of body mass index (BMI) values. 相似文献
999.
R Esturau P Iturralde S Férez O Galván J Rosado G Pérez J A González Hermosillo 《Archivos del Instituto de Cardiología de México》1991,61(3):205-210
From June 1988 to June 1990 we studied fifty patients who had implantation of a pacemaker. (31 females and 19 males). All of them underwent stress test with Bruce's protocol. Patients were divided in two groups; pacemaker-independent (PI) and pacemaker-dependent (PD). Over 50% of the patients inhibited the pacemaker with their own rhythm, most of them had sinus dysfunction. Complete A-V block was predominant in PD. The group of PI achieved more mets and had more oxygen consumption. Blood pressure response was similar in both groups. 相似文献
1000.
The variability of blood pressure measured by oscillometry and the validity of this technique were studied in premature infants. Thirty premature babies whose postnatal age was six days or more had their blood pressure measured 11 times over a twenty-minute period for three consecutive days. Movements were found to have a very substantial influence on results that could not be reliably compared with values obtained invasively. No consistent pattern of variations of oscillometric results obtained during the eleven measurements of use for recommending a specific measurement time was found. Diastolic blood pressure fell gradually over the three-day study period. The most reliable of the eleven daily values was the lowest value for which good correlations were found between the three study days; this lowest value was not influenced by neonatal or postnatal factors. 相似文献