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1.
To produce hybrids, one member of the parental line is genetically made male-sterile. This male-sterile trait is encoded by mitochondria so that it is maternally inherited. Consequently, the progeny of a male-sterile plant is fully sterile. Nevertheless, during the handling of cytoplasmic male-sterile seed stocks, some mixture with seeds of the maintainer lines can occur. Up to the present time, the only way to check the homogeneity of the cytoplasmic male-sterile seed stock was to grow the plants until flowering time. We have developed a method which can be used immediately after the harvest, allowing us to check samples from both sunflower and sugar beet. We used the mitochondrial plasmid, present only in the maintainer lines, as a probe for the total nucleic acids prepared from the cytoplasmic male-sterile seed stocks which might be contaminated. The signals compared to those of samples artificially contaminated allow us to measure as few as one male-fertile seed in 1000 seeds in a rapid and accurate manner. 相似文献
2.
J Pillet P Mercier P Cronier P Moreau F Lescalie J M Chevalier B Enon J F Jaeger C Caron Poitreau D Rieux 《Bulletin de l'Association des anatomistes》1986,70(210):69-74
The isolated azygos continuation of the inferior vena cave is a very rare variation of this organ. It is accompanied by the absence of the retrohepatic segment of the vena cava with two new observations, the literature is revised and the origin discussed. 相似文献
3.
George Lourenço PhD Sabine Meunier MD PhD Marie Vidailhet MD PhD Marion Simonetta‐Moreau MD PhD 《Movement disorders》2007,22(4):523-527
A decrease of heteronymous median nerve-evoked inhibition of corticospinal projections to forearm extensor muscles was reported in a group of 10 dystonic patients by Bertolasi and colleagues in 2003. Here we tested the excitability of corticomotoneuronal connections to both wrist extensor (ECR) and flexor (FCR) muscles after conditioning stimulation of median and also radial nerve at rest in a group of 25 patients with focal hand dystonia compared to 20 healthy subjects. We also investigated the effect of the wrist dystonic posture, either in flexion or in extension, on the afferent modulation of ECR and FCR motor evolved potentials (MEPs). The heteronymous (median-induced) but also homonymous (radial-induced) inhibitions (interstimuli intervals 13-21 ms) of ECR MEP size observed in healthy subjects were decreased in patients. In addition, homonymous (median-induced) facilitation of FCR MEP size was also decreased in patients while heteronymous inhibition (radial-induced) was not. Neither the involvement of the target muscle in the dystonic posture nor the origin of the afferent volley (from a dystonic muscle) influenced the degree of impairment of afferent modulation of the MEP. These findings support the view that a global abnormal somatosensory coupling in focal hand dystonia may contribute to an inadequate motor command to wrist muscles. 相似文献
4.
C Gaudin A Braillon R Moreau D Roulot A Hadengue D Lebrec 《Gastroentérologie clinique et biologique》1992,16(6-7):498-503
This study was designed to evaluate the renal contribution to overall sympathetic nerve hyperactivity and the relationships between renal sympathetic activity and systemic, splanchnic or renal hemodynamics in a series of 55 cirrhotic patients. Plasma noradrenaline concentrations were significantly higher in the renal vein than in the pulmonary artery (803 +/- 54 vs 608 +/- 47 pg/ml, P less than 0.01). These two concentrations were significantly correlated, which suggests that renal sympathetic activity and overall sympathetic activity increase in parallel in patients with cirrhosis. However, the estimated renal net release of noradrenaline was not correlated with plasma noradrenaline concentration in the pulmonary artery, suggesting that overall sympathetic nerve activity is not directly dependent on renal contribution in patients with cirrhosis. Neither plasma noradrenaline concentration in the renal vein nor renal net release of noradrenaline were correlated with systemic. splanchnic or renal hemodynamics. Thus, this study did not show a major role of renal sympathetic activity in the hemodynamic changes in cirrhosis. 相似文献
5.
J J Pessey G Fourtanier J P Chavoin G A Moreau E Serrano L M Martinez 《Archives of oto-rhino-laryngology》1989,246(5):384-387
The authors report their surgical experiences with 55 extensive tumours of the pharyngoesophageal junction. Thirty-three of these cases were managed by circular pharyngolaryngectomy, total oesophagectomy with stripping and left coloplasty, and 22 were treated with circular pharyngolaryngectomy with free intestinal transplants. A comparative study of the post-operative courses of the patients and their oncological and functional outcomes shows the advantages, disadvantages and indications of these two techniques. 相似文献
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Correction of severe secondary hyperparathyroidism in two dialysis patients: surgical removal versus percutaneous ethanol injection. 总被引:1,自引:0,他引:1
B Page J Zingraff J C Souberbielle G Coutris E Sarfati T Drüeke J F Moreau 《American journal of kidney diseases》1992,19(4):378-381
Two chronic hemodialysis patients had recurrent, severe secondary hyperparathyroidism. The first had no sonographically visible parathyroid gland in the neck. Computed tomography (CT) scan indicated the existence of a parathyroid mass in the upper mediastinum, which was removed surgically. The second patient had two intracervical, hyperplastic parathyroid glands visible on ultrasound examination. He volunteered for nonsurgical removal via sonographically guided percutaneous injection of ethanol. In both patients, serum total calcium concentration decreased dramatically to values near 1.5 mmol/L 24 hours after treatment. In patient 1, serum immunoreactive parathyroid hormone (iPTH) (1-84) decreased from 1,582 pg/mL before surgery to 34 pg/mL after 24 hours (normal range, 10 to 65 pg/mL). In contrast, serum iPTH (1-84) decreased only progressively in patient 2, from 1,680 pg/mL before ethanol injection to 865 pg/mL after 24 hours and to 378 pg/mL after 72 hours to reach 30 pg/mL after 14 days. Thus, patient 2 had a striking decrease of plasma calcium immediately after parathyroid gland destruction, even though circulating iPTH was still very high. The reason for such a discrepancy remains unexplained at present, and further study will be necessary to solve this issue. 相似文献
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Polymorphism and drug-selected mutations in the protease gene of human immunodeficiency virus type 2 from patients living in Southern France 下载免费PDF全文
Colson P Henry M Tourres C Lozachmeur D Gallais H Gastaut JA Moreau J Tamalet C 《Journal of clinical microbiology》2004,42(2):570-577
The susceptibility of human immunodeficiency virus type 2 (HIV-2) to protease inhibitors (PI) is largely unknown. We studied HIV-2 protease genes from 21 HIV-2-infected patients who were exposed or not exposed to PI. The aim of this study was (i). to characterize the polymorphism of HIV-2 protease in the absence of drug, (ii). to know whether the HIV-2 protease gene naturally harbors HIV-1 drug resistance codons, and (iii). to identify mutations emerging under PI-selective pressure. Sixty-five HIV-2 RNA or proviral DNA samples were directly sequenced from the plasma or peripheral blood mononuclear cells of 8 patients who had received PI and 13 patients who had never received any antiretroviral. In untreated patients, the highest amino acid variability in HIV-2 protease was observed at positions 14, 40, 43, 46, 65 and 70, and seven codons (10V, 32I, 36I, 46I, 47V, 71V, and 73A) associated with drug resistance in HIV-1 were highly prevalent. In addition, at six positions (positions 7, 46, 62, 71, 90, and 99), the amino acid variability or the amino acid frequencies or both differed significantly in PI-treated and untreated patients, suggesting that mutations 7K-->R, 46V-->I, 62V-->A/T, 71V-->I, 90L-->M and 99L-->F were occurring under PI-selective pressure. At these positions, at least one sample simultaneously harbored both wild-type and mutated codons, while substitutions at positions 62, 71, 90, and 99 were confirmed in a longitudinal analysis. Moreover, the presence of codons 46I and 99F in the absence of drug in HIV-2 subtype B proteases may reflect natural resistance to PI. In conclusion, the present study revealed that HIV-2 strains harbor specific patterns of natural polymorphism and resistance. 相似文献