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11.
Albertine Dubois Julien Dauguet Anne-Sophie Herard Laurent Besret Edouard Duchesnay Vincent Frouin Philippe Hantraye Gilles Bonvento Thierry Delzescaux 《Journal of cerebral blood flow and metabolism》2007,27(10):1742-1755
Besides the newly developed positron emission tomography scanners (microPET) dedicated to the in vivo functional study of small animals, autoradiography remains the reference technique widely used for functional brain imaging and the gold standard for the validation of in vivo results. The analysis of autoradiographic data is classically achieved in two dimensions (2D) using a section-by-section approach, is often limited to few sections and the delineation of the regions of interest to be analysed is directly performed on autoradiographic sections. In addition, such approach of analysis does not accommodate the possible anatomical shifts linked to dissymmetry associated with the sectioning process. This classic analysis is time-consuming, operator-dependent and can therefore lead to non-objective and non-reproducible results. In this paper, we have developed an automated and generic toolbox for processing of autoradiographic and corresponding histological rat brain sections based on a three-step approach, which involves: (1) an optimized digitization dealing with hundreds of autoradiographic and histological sections; (2) a robust reconstruction of the volumes based on a reliable registration method; and (3) an original 3D-geometry-based approach to analysis of anatomical and functional post-mortem data. The integration of the toolbox under a unified environment (in-house software BrainVISA, http://brainvisa.info) with a graphic interface enabled a robust and operator-independent exploitation of the overall anatomical and functional information. We illustrated the substantial qualitative and quantitative benefits obtained by applying our methodology to an activation study (rats, n=5, under unilateral visual stimulation). 相似文献
12.
Recommendations for the diagnosis and management of Alzheimer's disease and other disorders associated with dementia: EFNS guideline 总被引:4,自引:0,他引:4
G. Waldemar B. Dubois M. Emre J. Georges I. G. McKeith M. Rossor P. Scheltens P. Tariska B. Winblad 《European journal of neurology》2007,14(1):e1-e26
The aim of this international guideline on dementia was to present a peer-reviewed evidence-based statement for the guidance of practice for clinical neurologists, geriatricians, psychiatrists, and other specialist physicians responsible for the care of patients with dementia. It covers major aspects of diagnostic evaluation and treatment, with particular emphasis on the type of patient often referred to the specialist physician. The main focus is Alzheimer's disease, but many of the recommendations apply to dementia disorders in general. The task force working group considered and classified evidence from original research reports, meta-analysis, and systematic reviews, published before January 2006. The evidence was classified and consensus recommendations graded according to the EFNS guidance. Where there was a lack of evidence, but clear consensus, good practice points were provided. The recommendations for clinical diagnosis, blood tests, neuroimaging, electroencephalography (EEG), cerebrospinal fluid (CSF) analysis, genetic testing, tissue biopsy, disclosure of diagnosis, treatment of Alzheimer's disease, and counselling and support for caregivers were all revised when compared with the previous EFNS guideline. New recommendations were added for the treatment of vascular dementia, Parkinson's disease dementia, and dementia with Lewy bodies, for monitoring treatment, for treatment of behavioural and psychological symptoms in dementia, and for legal issues. The specialist physician plays an important role together with primary care physicians in the multidisciplinary dementia teams, which have been established throughout Europe. This guideline may contribute to the definition of the role of the specialist physician in providing dementia health care. 相似文献
13.
Philippe Dege Philippe Dubois Robert Jrme 《Macromolecular chemistry and physics.》1997,198(6):1985-1995
The thermal stability of poly(L -lactide) and L /D -lactide stereocopolymers polymerized in bulk with aluminium isopropoxide as initiator was investigated by thermogravimetric analysis, and time and temperature dependence of molecular weight and polydispersity. Compared to poly(L -lactide) prepared with stannous octoate as catalyst the thermal stability of polylactides is remarkably enhanced when the ring-opening polymerization is initiated by aluminium alkoxide. Ultimate mechanical properties and viscoelasticity of these melt-stable thermoplastics have also been studied in relation to the polyester enantiomeric composition. 相似文献
14.
Laurent Garel Josée Dubois Fran?oise Rypens Alain Ouimet Salam Yazbeck 《Journal l'Association canadienne des radiologistes》2004,55(1):39-44
OBJECTIVE: To report on the high incidence of anatomical variants of the origin and course of the internal spermatic vein (ISV) discovered at the time of percutaneous embolization of left varicoceles in a pediatric population. METHODS: We reviewed retrospectively the 65 cases of left varicocele treated by percutaneous embolization (grade II and III) in our institution between 1990 and 2000. The course of the left renal vein (LRV), the origin of the ISV, and the number of ISVs and their pathway were recorded in all cases, according to the B?hren classification. RESULTS: In 37/65 (57%), the ISV was single and arose from a normal LRV (type I). The following variants were encountered: type V--circumaortic LRV 9/65 (14%); type IVb--intrarenal origin of ISV 8/65 (12%); type II--multiple ISV 5/65 (8%); and pelvic collaterals 6/65 (9%). CONCLUSION: Venous anatomical variants are frequently encountered (43%) at the time of left varicocele embolization in children. Such variants often impose some adjustments to the technique of embolization and, at times, hamper the procedure. 相似文献
15.
This study was carried out to test whether women who think they know when they ovulate, really know. Fifty-three women of age 18.7 to 46.1 (mean age 28.4 years) participated in initial interviews about ovulation. Criteria for recruitment included perceived ovulation, regular menstrual cycles, and not using hormonal contraception. Women collected and refrigerated urine samples from day 5 until they thought they ovulated. Samples collected within 48 h of the perceived signal were then tested for a pre-ovulatory LH surge. Of the 53 original participants, 36 women provided urine samples for 1-6 cycles, so that 87 cycles were tested. Subjective signals of ovulation varied between women and between cycles but included abdominal pain and changes in cervical discharge, libido, and mood. Of the 87 cycles tested, during which women identified one or multiple signals of ovulation, 37 of the 87 urine specimens tested positive for an LH surge for a concordance rate of 42.5%. Using the first tested cycle from the 36 women who provided urine specimens, 13 of those specimens demonstrated an LH surge, for a concordance rate of 36.1%. That rate dropped to 28% (7/25) when women who used basal body temperature as an ovulatory signal were excluded. Finally, the mean level of accuracy among the 15 women who contributed 3-6 urine specimens for testing was 48.9%. The results of this study demonstrate a low degree of concordance between LH surge and perceived ovulation among women who think they know when they ovulate. The most motivated study participants were right about half of the time. Although there is variation among women in their ability to know when they ovulate, this study suggests that, for most women, ovulation is concealed. 相似文献
16.
Like enteroviruses, hepatitis A virus (HAV) hemagglutinated various species of erythrocytes under similar conditions. HAV-specific antibodies in both acute- and convalescent-phase sera were found to inhibit hemagglutination. The HAV hemagglutination inhibition test can be used for diagnosis, epidemiological surveillance, and vaccine assessment. 相似文献
17.
Encephalomyocarditis (EMC) virus replicates to high titre in permissive mouse kidney (MKS) cells but poorly in monkey kidney (CV1) cells. The permissiveness of monkey-mouse hybrid cells varies according to their chromosomal content. In monkey cells, the synthesis of both single-stranded and double-stranded virus RNA is restricted; in semi-permissive hybrid clones, the double-stranded RNA is synthesized normally, whereas the synthesis of the single-stranded RNA is inhibited. Thus, it seems that more than one restrictive event is responsible for the low permissiveness of monkey cells to EMC virus. 相似文献
18.
19.
Nathalie Sints-Zydowicz Quang Tho Pham Jacque Dubois Philippe Michaud 《Macromolecular chemistry and physics.》1997,198(7):2017-2026
In depth study of low molecular weight poly(imide-amide)s (PIA) obtained by copolycondensation of 4,4′-methylenedi(phenyl isocyanate), trimellitic anhydride and benzoic acid by 1H and 13C NMR spectroscopy and size-exclusion chromatography allows the determination of their absolute number-average molecular weights M?n, abs. Viscosimetric measurements reveal that, dissolved in N-methyl-2-pyrrolidone, these low molecular weight PIAs should be semi-rigid because of the presence of very short crystalline chains. By using the semi-empirical Fox-Flory relation, the extrapolated glass transition temperature equals 300°C for high molecular weight. 相似文献
20.
L Léger Y Charnay J A Chayvialle A Bérod F Dray J F Pujol M Jouvet P M Dubois 《Neuroscience》1983,8(3):525-546
The distribution of tyrosine hydroxylase-, substance P- and enkephalin-immunoreactive neurons in the cat dorsolateral pons was studied using the indirect immunofluorescence method of Coons. To allow for the visualization of substance P- and enkephalin-immunoreactive cell bodies, colchicine was injected either in the ventricular space or in the cerebral tissue. The distribution of the tyrosine hydroxylase-immunoreactive cell bodies corresponded with the well-known distribution of catecholamine cells in this area of the brain. The observation of adjacent sections treated separately with tyrosine hydroxylase- and enkephalin-antiserum revealed that most catecholaminergic cells contain enkephalin-immunoreactivity. In addition to this catecholamine-enkephalin cell population, a moderate number of substance P-immunoreactive cell bodies was found in dorsolateral pons. The peribrachial nuclei were found to be densely supplied with substance P- and enkephalin-immunoreactive fibers, whereas the medial subdivisions, which contain the majority of the catecholamine cells in the dorsolateral pons, display a moderate number of immunoreactive fibers. These results are suggestive of interactions between peptide-containing and catecholaminergic neurons and also between-peptide-containing and non-catecholamine-containing neurons in the cat dorsolateral pons. 相似文献