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1.
The effects of the destruction of mixed dopamine/neurotensin (DA/NT) meso-cortical neurons were investigated by studying the development of denervation supersensitivity of DA (D1) and NT cortical post-synaptic binding sites using respectively [3H]SCH 23390 and [125I]NT as ligands. These neurons were destroyed bilaterally either by injection of 6-hydroxydopamine (6-OHDA) or by an electrolytic coagulation made in the ventral tegmental area (VTA). Five weeks later, both [3H]SCH 23390 and [125I]NT bindings were analysed by quantitative autoradiography on each lesioned animal and on corresponding controls. The chemical lesions of the VTA induced an increase in the density of the cortical NT binding sites but did not affect D1 binding sites. On the contrary, electrolytic lesions induced an increase in D1 binding sites and no change in NT binding sites. One possible explanation of these differences may be that, since chemical lesions of the VTA destroy noradrenergic (NA) ascending pathways while electrolytic lesions spare the cortical NA innervation, the observed modifications of D1 and NT cortical binding sites following their presynaptic denervation are dependent on the presence (increase in D1 receptors) or the absence (increase in NT binding sites) of the cortical NA innervation.  相似文献   
2.
OBJECTIVE: To evaluate the influence of a brief period of sleep deprivation on cardiac autonomic controls during sleep in healthy infants. DESIGN: Twelve healthy infants with a median age of 8 weeks (range, 7 to 18 weeks) were recorded polygraphically during a morning and an afternoon nap in a sleep laboratory. They were sleep deprived for approximately 2 hours, either in the morning or in the afternoon, before being allowed to fall asleep. Six infants were sleep deprived before the morning nap, and 6 before the afternoon nap. During both naps, their sleep, breathing, and heart-rate characteristics were continuously recorded. Spectral analysis of heart rate was evaluated as a function of sleep stages. Two major peaks were recognizable: a low-frequency component related to sympathetic and parasympathetic activities and a high-frequency component reflecting parasympathetic tonus. The ratio of low-frequency to high-frequency powers was calculated as an index of sympathovagal interaction. RESULTS: When sleep deprived, the infants had an increase in basal heart rate during non-rapid eye movement sleep (P=.021). With sleep deprivation, the ratio of low-frequency to high-frequency powers increased in non-rapid eye movement sleep (P=.005). These findings were consistent with an increase in sympathetic tone. CONCLUSION: Infants exposed to short-term sleep deprivation manifest changes in cardiac autonomic controls during sleep. These findings could be relevant to mechanisms associated with the sudden infant death syndrome.  相似文献   
3.
Imatinib mesylate (tested as STI571), an abl kinase inhibitor, induces sustained, complete hematologic and cytogenetic responses in chronic myelocytic leukemia (CML) patients; however, emergence of clonal chromosomal aberrations in Philadelphia-negative (Ph-) cells during treatment has been reported. We describe two CML patients in chronic phase who presented with complete cytogenetic responses during imatinib mesylate therapy but developed new clonal chromosomal rearrangements in Ph- cells. The first patient presented with a duplication of chromosome 1, dup(1)(q21q42), and the second showed two new clonal aberrations consisting of inv(1)(q12q32) and del(7)(q22) in the same clone.  相似文献   
4.
Pretreatment of rats with the extract of Ginkgo biloba termed EGb761 reduced the behavioral sensitization induced by successive -amphetamine administrations (0.5 mg/kg) as estimated by increasing values of locomotor activity. EGb761 pretreatment also prevented the reduced density of [3H]dexamethasone binding sites in the dentate gyrus and the CA1 hippocampal regions of -amphetamine treated animals. These observations suggest that EGb761, by reducing glucocorticoid levels, could modulate the activity of the neuronal systems involved in the expression of the behavioral sensitization.  相似文献   
5.
Impact of Recalls on ICD Utilization . Introduction: The study was designed to evaluate the feasibility and performance of right ventricular (RV) mid‐septal versus apical implantable defibrillator (ICD) lead placement. Methods and Results: SEPTAL is a randomized, noninferiority trial, which randomly assigned patients to implantation of ICD leads in the RV mid‐septum versus apex, with a primary objective of comparing the implant success rate of implant at each site, based on strict electrical predefined criteria. We also compared the (1) pacing lead characteristics, (2) rates of appropriate and inappropriate ICD therapies, and (3) all‐cause mortality between the 2 sites at 1 year. The trial enrolled 215 patients (mean age = 59.7 ± 12.4 years, mean LVEF = 34.0 ± 14.2%, 84.2% men), of whom 148 (68.8%) presented with ischemic heart disease. The ICD indication was primary prevention in 117 patients (54.4%). The lead was successfully implanted in 96/107 patients (89.7%) assigned to the RV mid‐septum, and in 99/108 (91.7%) assigned to the apex (ns). The 1‐year rate of lead‐related adverse events was similar in both groups. A total of 8 first inappropriate ICD therapies (7.9%) were delivered in the RV mid‐septal group, versus 8 (7.8%) in the apical group (ns), while first appropriate therapies were delivered to 22 (21.4%) and 24 patients (23.8%), respectively (ns). All‐cause mortality was 7.9% in the RV mid‐septal versus 2.9% in the RV apical group (ns). Conclusion: This study confirmed the technical feasibility and noninferior performance of ICD leads implanted in the RV mid‐septum versus the apex. (J Cardiovasc Electrophysiol, Vol. 23, pp. 853‐860, August 2012)  相似文献   
6.
OBJECTIVES: To study the usefulness of the combination of clonidine--spironolactone in refractory ascites. METHODS: Twenty cirrhotic patients with refractory ascites were randomly assigned to receive repeated large volume paracentesis plus intravenous albumin (group 1), or a combination of clonidine (0.075 mg twice daily) and spironolactone (200 to 400 mg daily) (group 2). RESULTS: During the first hospitalisation,, the mean weight loss in group 1 was higher than in group 2 (12.4 +/- 3.2 versus 4.3 +/- 1.1 kg, P < or = 0.01). Mean stay in hospital was shorter in group 2 (20 +/- 1.5 versus 10 +/- 2.8 days; P < or = 0.01). Paracentesis did not induce changes in neuro-hormonal measurements. Oppositely, clonidine induced a decreased sympathetic activity, an increased glomerular filtration rate and a delayed reduction of the renin-aldosterone levels. During the follow-up in group 1, the number of rehospitalisations for ascites was higher than in group 2 (37 versus 3; P < or = 0.01), and the mean time to the first readmission was shorter (10 +/- 2.7 versus 23.7 +/- 5.6 days; P < or = 0.01). The total duration spent in hospital were similar in both groups. CONCLUSION: Paracentesis is more effective for short-term treatment of ascites but clonidine-spironolactone association might provide better long-term control.  相似文献   
7.
A challenge in drug dependence is to delineate long-term neurochemical modifications induced by drugs of abuse. Repeated d-amphetamine was recently shown to disrupt a mutual regulatory link between noradrenergic and serotonergic neurons, thus inducing long-term increased responses to d-amphetamine and para-chloroamphetamine, respectively. We show here that such a sensitization of noradrenergic and serotonergic neurons also occurs following repeated treatment with cocaine, morphine, or alcohol, three compounds belonging to main groups of addictive substances. In all cases, this sensitization is prevented by alpha 1b-adrenergic and 5-HT2A receptors blockade, indicating the critical role of these receptors on long-term effects of drugs of abuse. However, repeated treatments with two non-addictive antidepressants, venlafaxine, and clorimipramine, which nevertheless inhibit noradrenergic and serotonergic reuptake, do not induce noradrenergic and serotonergic neurons sensitization. Similarly, this sensitization does not occur following repeated treatments with a specific inhibitor of dopamine (DA) reuptake, GBR12783. Moreover, we show that the effects of SCH23390, a D1 receptor antagonist known to inhibit development of d-amphetamine behavioral sensitization, are due to its 5-HT2C receptor agonist property. SCH23390 blocks amphetamine-induced release of norepinephrine and RS102221, a 5-HT2C antagonist, can reverse this inhibition as well as inhibition of noradrenergic sensitization and development of behavioral sensitization induced by repeated d-amphetamine. We propose that noradrenergic/serotonergic uncoupling is a common neurochemical consequence of repeated consumption of drugs of abuse, unrelated with DA release. Our data also suggest that compounds able to restore the link between noradrenergic and serotonergic modulatory systems could represent important therapeutic targets for investigation.  相似文献   
8.
The authors report two cases of splenic and hepatosplenic candidiasis occurring during a protracted neutropenia induced by chemotherapy for acute leukemia (lymphoblastic and myeloblastic respectively). Fungal infection was revealed by persistent or recurrent fever after correction of neutropenia. Diagnosis was suggested by findings at abdominal ultrasonography. It was confirmed by histological analysis which, in the first case, required open liver biopsy. In both cases, lack of improvement of splenic lesions despite treatment with Amphotericin B followed by fluconazole led to splenectomy. Both patients received postoperative anti fungal therapy with Ampho B and at one year's follow up, the patient who had the hepatosplenic candidiasis seems to have recovered.  相似文献   
9.
The aim of the present study was to describe linear growth of infants with celiac disease, using the "ICP-growth model". Supine length during the first three years of life was studied longitudinally in 63 infants with diagnosed celiac disease. "Undisturbed" linear growth was seen during the first six postnatal months followed by reduced growth during the second half of the first year. After 1.5 years of age a pattern of catch-up growth was observed, leading to an average attained length at 3 years of age similar to that of the controls. According to the "ICP-growth model", normal linear growth can mathematically be represented during the first 3 years of life by an Infancy component with the addition of a Childhood component, the latter acting from the second half of the first postnatal year. The onset of the Childhood component (assumed to represent the age at which growth hormone begins to influence linear growth significantly) was delayed by about an average of 3 months, which is in agreement with the observed reduction in gain during the second half of the first year of life. Children suffering from celiac disease and with "late" onset of the Childhood component were shorter at 1, 2 and 3 years of age than those with "normal" onset. The results of this investigation show that ICP-based growth charts are helpful in detecting and monitoring growth for children with celiac disease, and indicate a possible mechanism whereby malabsorption (and perhaps secondary malnutrition) leads to reduced growth velocity.  相似文献   
10.
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