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51.
Regnier V; Meddeb M; Lecointre G; Richard F; Duverger A; Nguyen VC; Dutrillaux B; Bernheim A; Danglot G 《Human molecular genetics》1997,6(1):9-16
Type 1 neurofibromatosis (NF1) gene encodes for a member of the GTPase
activating protein family and is considered to be a tumor suppressor gene.
Its very high rate of de novo mutation in humans led us to study a specific
feature of this gene: the presence of numerous NF1-related sequences.
According to our results, the human genome contains at least 11 NF1-related
sequences, nine of which are scattered near centromeric sequences of seven
different chromosomes. These NF1-related sequences, whose extent is quite
varied according to loci, are unprocessed copies of the NF1 gene, and bear
numerous mutations. A phylogenetic analysis of the six largest sequences
indicates that they are all derived from a common ancestor, which would
have appeared 22-33 million years ago, and was subsequently duplicated
several times during hominoid evolution. The most recent duplication and
interchromosomal transposition occurred in the last million years
suggesting that the process could still be ongoing. Intriguing similarities
between the evolution of alpha- satellite DNA and NF1-related sequences
suggest the involvement of a common genetic mechanism for the generation
and pericentric spreading of these NF1 partial copies.
相似文献
52.
In pinning a slipped capital femoral epiphysis (SCFE), the position of the pin within the center of the femoral head is important for two reasons. The pin may disrupt the lateral epiphyseal artery and cause avascular necrosis (AVN), or pin penetration in certain locations may go unrecognized on radiographs. To place the pin accurately, the surgeon must be aware of where the femoral head lies in relation to the femoral neck and the shaft. Radiographs of models and of patients in various positions support the view that the femoral head in most cases of chronic SCFE rotates around the axis of the femoral neck and does not slip inferiorly. Therefore, the starting point for an in situ fixation device is the anterior femoral neck, the exact location depending on the amount of slipping. 相似文献
53.
Morphine place conditioning is differentially affected by CCKA and CCKB receptor antagonists. 总被引:2,自引:0,他引:2
In the present study we have examined the interaction between the selective cholecystokinin (CCK)A and CCKB receptor antagonists, devazepide and L365-260 on morphine conditioned place preference (CPP). Using an unbiased procedure, morphine (1.5 mg/kg) produced a reliable CPP which was observed irrespective of the conditioning compartment type. Pretreatment with devazepide (0.001-0.01 mg/kg s.c.) produced a dose related attenuation of this response. At higher doses (0.1-1 mg/kg) this antagonism became variable and dependent on the training compartment with blockade only observed when conditioning was to the white/rough textured environment. This profile has also been reported for the serotonin (5-HT)3 receptor antagonist ondansetron. The CCKB antagonist L365-260 (0.000001-0.01 mg/kg) failed to antagonize the morphine CPP, if anything a mild potentiation was observed. To study this further we examined the interaction between L365-260 (0.01 mg/kg) and a subthreshold dose of morphine (0.3 mg/kg). At these doses neither drug elicited CPP, however when co-administered a significant CPP was recorded. Finally, L365-260 at 1 mg/kg induced a mild but significant CPP when administered alone. These results suggest a differential role of CCK receptor subtypes on reward-related behaviour and complement previous studies suggesting bimodal effects of CCK systems on mesolimbic dopamine function. 相似文献
54.
D Nguyen I Abdul-Rasool D Ward J Hsieh D Kobayashi S Hadlock F Singer B Bloor 《Anesthesiology》1992,76(4):573-579
Dexmedetomidine (DMED) is a novel alpha 2 adrenergic agonist that has been shown to have potent analgesic and anesthetic sparing effects. This study was designed to investigate the effects of DMED, both alone and combined with isoflurane, on resting ventilation, the hypercapnic response, and the hypoxic response in dogs. When given alone, 1 microgram/kg decreased resting ventilation by 22% but at larger doses (10, 20, and 100 micrograms/kg) resting ventilation increased, doubling at 100 micrograms/kg. Doses of 10 micrograms/kg and greater caused a maximum depression of 60% in the slope of the hypercapnic response, but no dose had a significant effect on the hypoxic ventilatory response. A dose of 3 micrograms/kg of DMED reduced isoflurane MAC from 1.3% to 0.37%, and the ventilatory effects of this 1 MAC combination were intermediate between the awake values and those of isoflurane-anesthetized (1.3%) dogs. Atipamezole is a specific centrally acting alpha 2 receptor antagonist and when given with DMED in isoflurane-anesthetized dogs prevented the ventilatory depression. However, atipamezole alone also ventilatory stimulating effects, which may indicate tonic alpha 2 adrenergic activity. The ventilatory depression caused by DMED, either alone or combined with isoflurane, at doses that significantly reduce anesthetic requirements are relatively mild. 相似文献
55.
56.
Thanh GN Ton Mary Anne Rossing Deborah J Bowen Sengkeo Srinouanprachan Kristine Wicklund Federico M Farin 《Behavioral and brain functions : BBF》2007,3(1):22-10
Background
Genes involved in dopaminergic neurotransmission have been suggested as candidates for involvement in smoking behavior. We hypothesized that alleles associated with reduced dopaminergic neurotransmission would be more common in continuing smokers than among women who quit smoking. 相似文献57.
通瘀注射液盆腔给药法治疗外在型子宫内膜异位症的临床研究 总被引:2,自引:0,他引:2
目的 运用通瘀注射液在非直视下经输卵管盆腔给药对子宫内膜异位症 (EEMs)的治疗作用 ,探讨活血化瘀法对EEMs的作用机理及此给药法的优势。方法 将临床治疗的EEMs患者 60例随机分为治疗组 (通瘀注射液组 )和对照组 (丹那唑组 ) ,疗程各为 3个月。用药前后测定下列指标 :临床症状与体征、内分泌激素、血液流变学、癌抗原 12 5 (CA12 5)和子宫内膜抗体 (EMAb)的阳性率变化。结果 治疗组的临床症状与体征、血液粘滞度和红细胞压积、CA12 5和EMAb的阳性率均降低 ,卵泡刺激素 (FSH)、黄体生成素 (LH)、雌二醇 (E2 )和孕激素 (P)的含量均受到调节 ,与对照组相比 ,差异有显著性。而治疗组对内分泌的调节能力弱于对照组 ,但作用柔和、均衡。结论 通瘀注射液对EEMs的作用是通过清除月经时异位内膜的瘀血、水肿、改善微循环及组织供氧、调节免疫功能和内分泌紊乱而实现的 ,与丹那唑相比其副作用小、并以治本为主。盆腔给药法则可使药物直达病灶 ,见效快 相似文献
58.
Marenne P Budde Titia E De Lange Gus A Dekker Annabelle Chan Anh-Minh T Nguyen 《The journal of maternal-fetal & neonatal medicine》2007,20(9):687-693
OBJECTIVE: This study was undertaken in order to determine the risk factors for pregnancies complicated by placental abruption in a socio-economically disadvantaged region in metropolitan Adelaide. METHODS: This was a retrospective case-control study including all singleton pregnancies resulting in placental abruption between 2001 and 2005. RESULTS: The overall incidence of placental abruption was 1.0%; the overall perinatal mortality among the births with abruption was 13%. Univariate analyses showed the following significant risk factors for placental abruption: preterm pre-labor rupture of the membranes (PRE-PROM; odds ratio (OR) 4.79, 95% confidence interval (CI) 1.52-15.08), non-compliance with antenatal care (OR 2.93, 95% CI 1.06-8.90), severe intrauterine growth restriction (IUGR), and elevated homocysteine levels (OR 45.55, 95% CI 7.05-458.93). Severe IUGR was significantly more common in the abruption group compared with the control group (p = 0.032). In the multivariate analysis, PRE-PROM remained a significant independent risk factor for placental abruption. Marijuana use, domestic violence, and mental health problems were more common (borderline significance) in the abruption group. Smoking and preeclampsia were not found to be associated with placental abruption in this study. CONCLUSIONS: In this high-risk population, PRE-PROM and elevated homocysteine levels appear to represent the major risk factors for placental abruption. 相似文献
59.
对32例出血性梗塞研究分析,发现常出现于脑栓塞及大面积脑血栓病人。以治疗中病情突然加重或持久症状不改善为特征,动态CT检查对本病的诊断及治疗有重要意义。 相似文献
60.
J W Ellingboe W Spinelli M W Winkley T T Nguyen R W Parsons I F Moubarak J M Kitzen D Von Engen J F Bagli 《Journal of medicinal chemistry》1992,35(4):705-716
The synthesis and Class III antiarrhythmic activity of a series of 4-[(methylsulfonyl)amino]benzamides and sulfonamides are described. Selected compounds show a potent Class III activity and are devoid of effects on conduction both in vitro (dog Purkinje fibers) and in vivo (anesthetized dogs). Compounds having a 2-aminobenzimidazole group were found to be the most potent, and one compound having this heterocycle (5, WAY-123,398) was selected for further characterization. Compound 5 was shown to have good oral bioavailability and a favorable hemodynamic profile to produce a 3-fold increase of the ventricular fibrillation threshold and to terminate ventricular fibrillation, restoring sinus rhythm in anesthetized dogs. Voltage-clamp studies in isolated myocytes show that 5 is a potent and specific blocker of the delayed rectifier potassium current (IK) at concentrations that cause significant prolongation of action potential duration. 相似文献