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61.
62.
Brandenberger G Viola AU Ehrhart J Charloux A Geny B Piquard F Simon C 《Journal of sleep research》2003,12(3):173-180
Aging is commonly associated with decreased sleep quality and increased periodic breathing (PB) that can influence heart rate variability (HRV). Cardiac autonomic control, as inferred from HRV analysis, was determined, taking into account the sleep quality and breathing patterns. Two groups of 12 young (21.1 +/- 0.8 years) and 12 older (64.9 +/- 1.9 years) volunteers underwent electroencephalographic, cardiac, and respiratory recordings during one experimental night. Time and frequency domain indices of HRV were calculated in 5-min segments, together with electroencephalographic and respiratory power spectra. In the elderly, large R-R oscillations in the very-low frequency (VLF) range emerged, that reflected the frequency of PB observed in 18% of the sleep time. PB occurred more frequently during rapid eye movement sleep (REM) sleep and caused a significant (P < 0.02) increase in the standard deviation of normal R-R intervals (SDNN) and absolute low-frequency (LF) power. With normal respiratory patterns, SDNN, absolute VLF, LF, and high frequency (HF) power fell during each sleep stage (P < 0.01) compared with young subjects, with no significant sleep-stage dependent variations. An overall decrease (P < 0.01) in normalized HF/(LF + HF) was observed in the elderly, suggesting a predominant loss of parasympathetic activity which may be related to decreased slow-wave sleep duration. These results indicate that two distinct breathing features, implying different levels of autonomic drive to the heart, influence HRV in the elderly during sleep. The breathing pattern must be considered to correctly interpret HRV in the elderly. 相似文献
63.
Julie L Creelan Viola M Calvert David A Graham Samuel J McCullough 《Avian pathology》2006,35(2):173-179
A real-time polymerase chain reaction (PCR) assay was developed to specifically amplify infectious laryngotracheitis virus (ILTV) DNA from field samples. The 222-base-pair PCR fragment was amplified using primers located in a conserved region of the infected cell protein 4 gene that was demonstrated in this work to encompass a single nucleotide polymorphism. Subsequent restriction fragment length polymorphism (RFLP) analysis of real-time PCR amplified fragments from a range of ILTV isolates using the restriction endonuclease MspI enabled differentiation between older ILTV isolates that were prevalent in the 1960s prior to the availability of vaccine strains and more recent isolates that predominantly are identical to vaccine strains. The assay, using real-time PCR, RFLP and sequence analysis, was used to characterize two recent field cases of infectious laryngotracheitis from Northern Ireland. One of the field cases was demonstrated to be similar to older "wild-type" isolates, while the other field case was identified to have a concurrent ILTV infection of both "wild-type" and vaccinal type origin. The assay described here using real-time PCR and RFLP provides a rapid, specific method that enables detection and characterization of ILTV directly from field cases. 相似文献
64.
Background
Despite frequent and serious mental health problems after interpersonal traumatization, only a fraction of those affected by interpersonal violence seek formal help after the event. Reasons for this mismatch can be found in the individual help-seeking process but also in the individual's social environment. These social factors are explored based on a model describing the survivor's help-seeking process. 相似文献65.
66.
Ferraz AC Xavier LL Hernandes S Sulzbach M Viola GG Anselmo-Franci JA Achaval M Da Cunha C 《Brain research》2003,986(1-2):200-205
The immunostaining for tyrosine hydroxylase (TH) in the substantia nigra pars compacta (SNpc) and in the ventral tegmental area (VTA) after intranigral infusion of 6-hydroxydopamine (6-OHDA, 6 microg/side) was analyzed in ovariectomized adult female Wistar rats. Estrogen replacement for 52 days (400-microg 17-beta-estradiol capsules) did not prevent the loss of TH-immunoreactive cells induced by 6-OHDA in the SNpc. This result indicates that the neuroprotective effect of dopaminergic mesencephalic cells is not observed with long-term estrogen replacement. 相似文献
67.
Palmieri S Sebastio L Mele G Annunziata M Annunziata S Copia C Viola A De Simone M Pocali B Schiavone EM Ferrara F 《Leukemia research》2002,26(6):539-543
Seventeen patients affected by acute myeloid leukemia (AML) with t(8;21) were prospectively programmed to receive three courses of high-dose cytarabine (HDARA-C) as post-remission therapy. The median age was 39 years and in all cases t(8;21) was the only karyotypic abnormality. Complete remission (CR) was achieved in 14 out of 17 cases (82%) and, after first consolidation with NOVIA regimen (intermediate dose ARA-C plus mitoxantrone), all patients received the three planned courses of HDARA-C (3g/m(2) q12h on days 1, 3, 5). There were two documented infections, while all patients experienced fever of unknown origin (FUO). Nonhematological toxicity was mild. Thirteen out of 14 patients are in continuous CR after a median follow-up of 44 months. One patient relapsed at 16 months and, following CR2 achievement, underwent allogeneic transplantation; he died 3 months later while in CR from acute graft versus host disease (GVHD). Survival at 5 years is projected at 79%. Our data confirm the efficacy of repeated courses of HDARAC for patients with t(8;21) AML. 相似文献
68.
Dahmen N Jungblut PR Fischer V Schrank M Reuss S Rujescu D Hiemke C 《Progress in neuro-psychopharmacology & biological psychiatry》2002,26(4):693-698
The molecular mechanisms by which antipsychotic effects are achieved remain largely elusive. Possible mechanisms include the modulation of nerve cell gene expression. The antipsychotic drug haloperidol was administered orally (1.6 mg/kg) to adult rats for 3 weeks. Protein patterns in striata and forebrains were studied by two-dimensional gel electrophoresis (2-DE). One differentially regulated protein spot was identified by matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) after trypsin digest. Turned on after devision-64 kD (TOAD-64), the identified protein, was present in all gels and, in addition, was up-regulated in the striata but not in the forebrains of the haloperidol-treated animals by 43%. It is concluded that TOAD-64, typically regarded as a marker for commitment to neuronal differentiation during fetal development, also plays a role in adult rat forebrain and striatum and that its concentration is possibly modulated by haloperidol treatment. 相似文献
69.
70.
A Poloni P Leoni L Buscemi F Balducci R Pasquini M C Masia N Viola E Costantino G Discepoli P Corradini A Tagliabracci A Olivieri 《Leukemia》2006,20(2):329-335
The engraftment ability of mesenchymal cells was investigated in 26 patients receiving allogeneic transplantation from HLA-identical siblings with reduced-intensity conditioning (RIC). The stem cell source was bone marrow (BM) in eight patients and G-CSF-mobilized peripheral blood hematopoietic cells in 18 cases. A total of 32 patients engrafted very quickly and the chimerism evaluation (both on myeloid and on lymphoid subsets) showed that they were full donor by day 60. At the time of the study they were in complete hematological remission and displayed a full donor hematopoiesis. Two patients showed early disease progression while one did not engraft. Forty-eight out-marrow samples harvested from the 26 patients generated a marrow stromal layer adequate for the chimerism evaluation. Monocyte-macrophage contamination of marrow stromal layers was always reduced below 2% by repeated trypsinizations and treatment with the leucyl-leucine (leu-leu) methyl ester. The chimerism evaluation was performed by PCR analysis of STRs microsatellites and the amelogenin locus, by using capillary electrophoresis (CE) and by FISH analysis in case of the sex mismatch. In eight patients, a partial donor origin of stromal cells was shown (7-86% cells of donor). The source of hematopoietic cells was BM in three patients and mobilized peripheral blood in the other five. 相似文献