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61.
Intracerebral injections of 6-hydroxydopamine directly in the nucleus locus coeruleus were performed in 4-day-old rats. The effects of such treatment on the subsequent development of this nucleus were analyzed and compared to those obtained in vehicle-injected age-paired controls. The 3 histological techniques used (Nissl, Glenner reaction, and histochemical fluorescence) indicated in the experimental group a progressive disappearance of the coerulean perikarya within 7 days postinjection. This lesion was permanent and did not induce any noradrenergic sprouting.  相似文献   
62.
Which are the main features associated with taste loss in patients exposed to a wide range of drugs and diseases? In 100 consecutive patients admitted to a ward of internal medicine, we assessed taste complaints, performance status, alcohol and tobacco consumptions, diseases, drugs and laboratory data, measuring the electrical taste threshold as primary outcome. After adjusting for age, taste thresholds were not associated with sex, body mass index, tobacco, thrush, drugs, aliageusia and phantogeusia. Features associated with threshold increase included alcohol intake>or=10 gd-1, impaired performance status, complaint of taste loss, atrophic glossitis, cerebral disease, and an erythrocyte mean corpuscular volume. A multivariate analysis identified age, alcohol intake, complaint of loss or altered taste, mean corpuscular volume, and performance status as independent factors associated with taste loss. Inpatients may be screened for taste loss by a few features, to identify those for whom a nutritional intervention should be focused.  相似文献   
63.
Thieno analogues of kenpaullone have been synthesized using an established method. We investigated the effect of five structural analogues of kenpaullone on vincristine sensitive and resistant MCF7 (human mammary adenocarcinoma) cells. One analogue, 8-Bromo-6,11-dihydro-thieno-[3',2':2,3]azepino[4,5-b]indol-5(4H)-one (3a), showed an antiproliferative activity in the drug sensitive cell line that led to cell accumulation in G2/M phase. In addition, repression of cdk1, a G2/M transition key regulator, as well as induction of p21 were observed at the mRNA level. Programmed cell death (apoptosis) was induced in early time treatments and was accompanied by p53 mRNA induction. The antiproliferative and proapoptotic properties of 3a make this CDK inhibitor an interesting candidate for further investigations.  相似文献   
64.
Sleep is the main behavioral state of the premature infant. In adult intensive care units, sleep deprivation has been reported as one of the major stressors. Developmental care (DC) aims to decrease stressful events in neonatal intensive care unit and support well-being. AIM: To assess whether DC is accompanied by changes in sleep in preterm neonates. METHODS: A prospective cross-over study included 33 preterm neonates [mean (S.D.): gestational age: 29.3 (1.8) weeks; birth weight: 1245 (336) g]. Polysomnography was performed in two randomly ordered 3-h periods with and without DC. A blinded electrophysiologist analyzed sleep. The total sleep time (TST) was the primary outcome, duration of active (AS), quiet (QS) and indeterminate sleep, and latency before sleep were the secondary outcomes. Non-parametric Wilcoxon tests and ANOVA were used. RESULTS: In DC condition vs. control: TST increased [in minutes, mean (S.E.M.): 156.2 (2.9) vs. 139.2 (4.6), p=0.002], with increase in AS [86.6 (3.7) vs. 77.0 (4.2), p=0.024] and in QS [47.1 (4.1) vs. 36.9 (4.2), p=0.015], and sleeping latency decreased (2.1 (0.7) vs. 10.5 (2.0), p=0.0005]. CONCLUSION: DC promoted sleep in our study. The impact of DC on the neuro-behavioral outcome needs futures studies.  相似文献   
65.
BACKGROUND: Left ventricular ejection time (LVET) measured in central arteries is modified during hypovolemia. We compared modifications of the pulse wave in a central artery (carotid) and in a peripheral artery (digital) during central hypovolemia induced by lower body negative pressure (LBNP) in conscious volunteers. METHODS: Hypovolemia was simulated with progressive LBNP (baseline, -10, -20, and -30 mm Hg) in nine young healthy volunteers. The carotid arterial pressure waveform was recorded using a Millar tonometric method. The digital pulse wave was measured with a volume-clamp method (Finapres) and the stroke volume with a thoracic impedance method (Biomed). RESULTS: Mean arterial pressure did not change during LBNP. Compared with baseline values, heart rate increased significantly at the -30 mm Hg level (68 +/- 13 beats/min vs. 59 +/- 11 beats/min), and stroke volume decreased as soon as -10 mm Hg was achieved (113 +/- 41 mL vs. 127 +/- 35 mL). Both carotid and digital LVET decreased significantly at the -10 mm Hg level (337 +/- 26 and 339 +/- 24 ms vs. 360 +/- 35 and 361 +/- 24 ms, respectively). CONCLUSION: Peripheral LVET could reflect variation of central LVET during LBNP and be a reliable noninvasive parameter for monitoring hypovolemia.  相似文献   
66.
67.
Clinical reports on autism describe abnormal responses to auditory stimuli such as intolerance to sounds. The present study assessed subjective perception of loudness in subjects with autism compared to healthy controls, using two psychoacoustic tests. First, the auditory dynamic range was evaluated at six different tone frequencies. Secondly, loudness growth as a function of the intensity level of a 1 kHz tone was estimated. Verbal responses from a group of 11 children and adolescents with autism were compared to responses of 11 age- and gender- matched healthy controls. Smaller auditory dynamic ranges were found in the autistic group than in the control group, as well as increased perception of loudness, indicating hyperacusis in subjects with autism.  相似文献   
68.
Immune repertoires of T or B cells are very often studied by Complementary Determining Region 3 (CDR3) spectratyping. However, data obtained with this method is usually subject to a biased eye analysis. We developed recently the ISEApeaks software package to retrieve and handle peak data from automated sequencers, from which CDR3 spectratype data is obtained. We describe a general strategy for CDR3 spectratype analysis based on two new specific modules and multivariate statistics. The first module addresses the crucial problem of peak smoothing. The second is a toolbox for the analysis of CDR3 spectratypes, which includes perturbation computation, recurrent peak finding, expansion assessment and datamining. To illustrate our approach, we assessed the complex TCRB repertoire modifications induced by Plasmodium berghei ANKA (PbA) infection. This global and exhaustive repertoire analysis approach is of general interest for T- and B-lymphocyte repertoire studies and is currently used in human cohorts in various pathologies and during clinical trials.  相似文献   
69.
GENERAL CHARACTERISTICS: Gaucher's disease is a genetic disease of autosomal recessive transmission due to a deficit in a lysosomal enzyme: beta-glucocerebrosidase. The disease is characterised by deposits of glucosylceramide in the cells of the liver, spleen and bone marrow. Acute or chronic neurological forms (type 2 and 3) account for only 5% of patients suffering from Gaucher's disease and are less frequent than the non-neurological forms (type 1). CLINICAL AND BIOCHEMICAL MANIFESTATIONS: Gaucher's disease is associated with spleno- or hepato-megalia, asthenia, bone complications (Erlenmeyer flask deformity, osteopenia and osteonecrosis), as well as with haematological (thrombopenia, anaemia) or biochemical abnormalities (increase in angiotensin-converting enzyme, ferritin, tartrate-resistant acid phosphatase and chitotriosidase). Central nervous system involvement is only found in the type 2 and 3. Diagnosis relies on measurement of beta-glucocerebrosidase activity in the circulating leukocytes. REGARDING TREATMENT: Treatment with enzyme replacement (imiglucerase: recombinant enzyme preparation) improves the haematological abnormalities, hepatosplenomegalia and quality of life in a matter of a few months. Regression of the bone disorders is usually observed only after 3-4 years of treatment. Recently, gene therapy trials have successfully been started.  相似文献   
70.
The persistence of mycotoxins and their metabolites in agricultural products is a major safety concern because of their high resistance to all kinds of decontamination techniques. In this study, we evaluated the effectiveness of the pulsed light technology for the degradation of mycotoxins. We report that eight flashes of pulsed light destroyed of 84.5 ± 1.9, 72.5 ± 1.1, 92.7 ± 0.8 and 98.1 ± 0.2% of zearalenone, deoxynivalenol, aflatoxin B1 and ochratoxin in solution. The degradation of the molecules was monitored by HPLC and LC‐MS/MS analysis. We estimated the potential toxicity of zearalenone and deoxynivelenol after exposure to a pulsed light treatment using the Caenorhabditis elegans survival tests. The genotoxicity of aflatoxin B1 was also investigated using a complete Ames test. The results show that the treatment of zearalenone and deoxynivelenol by single or multiple flashes of pulsed light is associated with a stagnation or marginal decrease of the toxicity of the mycotoxins and that treatment of aflatoxin B1 by pulsed light can completely eliminate the mutagenic potential of this mycotoxin. This work provides the first demonstration of a nonthermal technology allowing mycotoxin destruction and inactivation of their mutagenic activity. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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