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991.
Visual hallucinations are a core feature of dementia with Lewy bodies. Their pathophysiology is not well understood, because neither clinical nor histological data have shown their basic mechanisms. Here, we report the presence of pale inclusions in the outer plexiform layer of the retina in a patient with dementia with Lewy bodies. These inclusions are related to cytoskeletal disorganization of the cones at ultrastructural level and modifications of the immunohistochemical pattern of distribution of synucleins in the retina. These modifications may participate in the visual impairment in dementia with Lewy bodies. 相似文献
992.
Boileau I Assaad JM Pihl RO Benkelfat C Leyton M Diksic M Tremblay RE Dagher A 《Synapse (New York, N.Y.)》2003,49(4):226-231
Microdialysis experiments in rodents indicate that ethanol promotes dopamine release predominantly in the nucleus accumbens, a phenomenon that is implicated in the reinforcing effects of drugs of abuse. The aim of the present study was to test the hypothesis in humans that an oral dose of ethanol would lead to dopamine release in the ventral striatum, including the nucleus accumbens. Six healthy subjects underwent two [(11)C]raclopride PET scans following either alcohol (1 ml/kg) in orange juice or orange juice alone. Subjective mood changes, heart rate, and blood-alcohol levels were monitored throughout the procedure. Personality traits were evaluated using the tridimensional personality questionnaire. PET images were co-registered with MRI and transformed into stereotaxic space. Statistical parametric maps of [(11)C]raclopride binding potential change were generated. There was a significant reduction in [(11)C]raclopride binding potential bilaterally in the ventral striatum/nucleus accumbens in the alcohol condition compared to the orange juice condition, indicative of increased extracellular dopamine. Moreover, the magnitude of the change in [(11)C]raclopride binding correlated with the alcohol-induced increase in heart rate, which is thought to be a marker of the psychostimulant effects of the drug, and with the personality dimension of impulsiveness. The present study is the first report that, in humans, alcohol promotes dopamine release in the brain, with a preferential effect in the ventral striatum. These findings support the hypothesis that mesolimbic dopamine activation is a common property of abused substances, possibly mediating their reinforcing effects. 相似文献
993.
994.
OBJECTIVE: Controversy exists regarding the relation between diabetes and nonischemic idiopathic cardiomyopathy (ICM), and only limited data on the incidence of ICM in adults with diabetes are available. Therefore, we used the 1995 Nationwide Inpatient Sample (NIS) to determine discharge rates and test the hypothesis that diabetes is independently associated with ICM. RESEARCH DESIGN AND METHODS: The 1995 NIS includes demographic and diagnostic data on all discharges from >900 representative hospitals in 19 states. ICD-9 codes were used to identify ICM, defined as discharges with a diagnosis of primary cardiomyopathy but without established risk factors for cardiomyopathy. Control subjects were selected by stratified random sampling by age to yield 10 per ICM case. The analyzed covariates included age, race, median income, diabetes, and hypertension. Multivariate logistic regression was used to conduct case-control analyses. RESULTS: Using sampling weights, we estimated that in 1995, the rate of hospital discharge for ICM among individuals diagnosed with diabetes was 7.6 per 1000. The prevalence of diabetes was substantially higher in the 44837 ICM vs. 450254 control subjects (26.6 vs. 17.2%), corresponding to a relative odds (RO) of 1.75 (95% CI 1.71-1.79). After adjusting for age, sex, race, hypertension, and median income using multiple logistic regression, diabetes remained significantly associated with ICM (RO 1.58, 95% CI 1.55-1.62). CONCLUSIONS: We concluded that diabetes is independently associated with ICM in the general U.S. population. 相似文献
995.
Lescanne E Moriniere S Gohler C Manceau A Beutter P Robier A 《The Journal of laryngology and otology》2003,117(4):256-260
Most clinical studies on carbon dioxide (CO2) (lambda = 10.6 mm) laser stapedotomy have been carried out with the laser guided by a conventional lens-based micromanipulator, with the attendant risks of correct aiming (HeNe) and surgical (CO2) beam misalignment. Hence, engineering advances have attempted to improve laser targeting as well as the spot size focus. The development of the mirror-based micromanipulator was a response to this need but no data concerning its use in stapes surgery is available. We performed a retrospective case-series review of patients treated for otosclerosis between 1992 and 2000. Primary laser stapedotomy was performed in 218 consecutive patients. In the first 78 procedures, the aiming beam (HeNe, lambda = 632 nm) and surgical beam (CO2) were guided with a conventional lens-based micromanipulator whereas in the subsequent 140 procedures, they were guided by using a mirror-based micromanipulator. Hearing was tested at six and 12 months. The mean (SD) airbone gap was 5 dB (4.5) and 4.5 dB (3.9). The mean closure was 15 dB (9.9) and 14.4 dB (9.4). The mean change in the high-tone bone-conduction level was 5.5 dB (7.3) and 7.8 dB (7.5). Overheating of the facial canal produced transient facial paralysis in one case and was due to misalignment of the beams with the lens-based micromanipulator. Use of the mirror-based micromanipulator obviated the need to verify alignment. The light-weight and superior optical yield of this system made it possible to reduce the number of impacts on the footplate by the integral restitution of the energy source. This study demonstrated that the CO2 laser is an effective method for performing stapedotomy. In addition, microtrauma to the labyrinth is reduced by its ability to perform calibrated footplate fenestration without mechanical or vibrational injury to the inner ear. The optical reflection micromanipulator simplified beam alignment and enhanced surgical comfort. 相似文献
996.
997.
The current European standards for microbiological quality of bathing water (i.e., all running or still fresh waters or parts thereof and/or sea water [with the exception of water intended for therapeutic purposes and water used in swimming pools]) were issued in 1976 and are currently undergoing revision. In this article, the authors propose parameters for select microorganism indicators to assist in the establishment of public-health-based objectives for fresh and marine water quality. A type-II meta-analysis of the results of 18 published epidemiological studies was implemented in an attempt to characterize the relationship(s) between concentrations of bacterial indicators and rates of acute gastrointestinal diseases among bathers who had used fresh or marine water for recreational purposes. The authors fit multiple linear-regression models, which allowed for random effects across studies, to derive dose-response curves. Several confounders and effect modifiers were controlled for in the analyses. Risks were then estimated for a hypothetical individual who would bathe 20 times/yr in water that contained a given concentration of microorganisms. For fresh-water-associated highly credible gastrointestinal illnesses, a level of 10 fecal coliforms/100 ml water yielded an attributable risk of 0.2 cases/1,000 person-years; a risk of 2 cases/1,000 person-years was found for fecal streptococci. The corresponding yearly attributable risks were 1 and 13 cases/1,000 person-years, respectively, for 100 bacteria/100 ml fresh water. Risks associated with fecal coliforms were found to be lower in marine water than in fresh water. Irrespective of the type of water examined, total coliforms were related only weakly with acute digestive morbidity. Developers of future bathing-water standards should state the level of risk deemed acceptable for public health. The authors of this study maintain that levels of fecal coliforms and fecal streptococci should be used as criteria for infectious risk management associated with bodies of marine and fresh water used for recreational purposes. 相似文献
998.
A national survey of sexologists was carried out in France in 1998–1999, among the individuals listed in the professional directories and the telephone book as sexologists. It described the sociodemographic characteristics of sexologists, their initial profession and training in sexology, sex therapy and psychotherapeutic techniques, and how they practice sexology. A total of 959 individuals were identified and surveyed. The response rate was 63%. Two thirds of the sexologists were physicians and 60% were men. French sexologists appeared to be segmented into three subgroups: (1) one-third were general practitioners, trained in sexology and psychotherapeutic approaches, recognized themselves as sexologists, and devoted 40% of their professional activity to sexology. Men were about two thirds of this group; (2) one-third were nonphysicians (including psychologists and other health professionals, such as social workers and nurses), recognized themselves as sex therapists and devoted one third of their time to sexology. Men and women were equally represented in this group; (3) one-third were specialists, with less training in sexology and psychotherapeutic techniques, and did not generally recognize themselves as sexologists. They devoted a lesser part of their time to sexology and had academic and hospital practice. Men comprised more than 75% of this group. This study raised the issue of the diversity of primary professions involved in the field of sexology and showed that sexology is a secondary professional choice for the majority of sexologists. 相似文献
999.
Ramin Tadayoni Michel Paques Pascale Massin Soraya Mouki-Benani Jacqueline Mikol Alain Gaudric 《Ophthalmology》2001,108(12):2279-2283
Purpose
To report the appearance of the fundus, that is seen frequently after removal of an idiopathic epiretinal membrane and which we refer to as the dissociated optic nerve fiber layer appearance.Design
Interventional, noncomparative retrospective case series.Participants
One hundred consecutive patients with an epiretinal membrane who underwent pars plana vitrectomy and epiretinal membrane peeling in one eye.Methods
Only patients with an idiopathic epiretinal membrane or a membrane associated with a peripheral retinal tear, but without retinal detachment, were considered for this study. Sixty-one patients met these criteria for one eye. Preoperative and postoperative best-corrected visual acuity and preoperative and postoperative blue filter fundus photographs were reviewed. Histopathologic specimens of epiretinal membranes were available for 14 eyes.Main outcome measures
The postoperative incidence of the dissociated optic nerve fiber layer appearance on blue filter photographs, visual acuity changes, and the presence of internal limiting membrane in epiretinal membrane specimens.Results
The postoperative incidence of this feature on blue filter fundus photographs was 43%. No difference was found between eyes with or without this feature concerning the average preoperative and postoperative best-corrected visual acuity or the average change in visual acuity. Internal limiting membrane was present in all 14 epiretinal membrane specimens available. Five of these 14 patients concerned exhibited a dissociated optic nerve fiber layer appearance and 9 did not.Conclusions
The dissociated optic nerve fiber layer appearance occurred frequently after removal of an epiretinal membrane. As far as we know, this feature has not been previously reported. It consisted of numerous arcuate striae within the posterior pole in the direction of the optic nerve fibers and slightly darker than the surrounding retina. This feature had no functional effect noticeable by the patient and did not preclude good visual recovery. The small number of histologic samples and the impossibility of quantifying the area of internal limiting membrane peeled off did not allow us to supply proof that this feature is due to the extensive peeling of the internal limiting membrane, although this is the most likely hypothesis. 相似文献1000.
Larno V Laroche J Launey S Flammarion P Devaux A 《Ecotoxicology (London, England)》2001,10(3):145-158
Indicators of effects at the population level (genetic variation using allozymes) and early indicators of pollution (EROD activity and DNA strand break formation) were analysed in chub (Leuciscus cephalus) living in weakly and heavily contaminated stations of the Rhône River watershed. The genetic erosion was mainly detected in a fish population living in a contaminated small river system, through modifications in allelic and genotypic frequencies for PGM-2 locus and could be linked to a genetic bottleneck and to the reduced gene flow from upstream unable to maintain or restore the genetic diversity. In a contaminated large river system, the genetic diversity for PGM-2 and other loci was maintained and was probably the consequence of a high gene flow from upstream, linked to a sustained drift of larvae and juveniles in the system. A convergent increase of the frequency of the 90 allele at PGM-2 was observed in two contaminated stations compared with the reference station, this trend being confirmed on a more extensive geographic scale over the Rhône River basin. A high level of EROD activity was detected in both contaminated sites but only the fish in the large river system showed a significant DNA damage level compared to the reference population. The low DNA damage level and high hepato-somatic ratio characterized the impacted population of the small river system and could be associated to a chronic high-level exposure of fish to pollutants which selected individuals exhibiting a high level of DNA damage repair. In the two contaminated systems, some genotypes at the PGM-2 and EST-2 loci showed a low level of DNA damage and/or a high EROD activity and may be considered as being tolerant to pollutants. A higher tolerance of the most heterozygous fish was also detected in the contaminated large system and confirmed that a high level of heterozygosity may be necessary for survival in such a system. 相似文献