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81.
82.
At two scientific conferences in 1985, one in Copenhagen sponsored by the Nordic Council of Ministers and the World Health Organization (WHO), the other in Raleigh, NC, it was concluded that chronic toxic encephalopathy may develop following long-term occupational exposure to organic solvents (1,2). The terms organic affective syndrome, mild and severe chronic toxic encephalopathy were suggested for this condition describing increasing severity. In May 1990, a conference on organic solvents and the nervous system was held in Copenhagen sponsored by the Commission of the European Communities and the Danish Ministry of the Environment (3). Scientists and representatives from the governments, industries, and labour organisations from the EEC and US participated. 相似文献
83.
E Masliah M Ellisman B Carragher M Mallory S Young L Hansen R DeTeresa R D Terry 《Journal of neuropathology and experimental neurology》1992,51(4):404-414
Recent studies have shown that the Alzheimer disease (AD) neocortex is characterized by a loss of large neurons, the presence of dilated terminal axons, widespread loss of synapses, and a disruption of the dendritic cytoskeleton which is manifested as Tau immunoreactive threads. In the present study we have investigated the relationship between synaptic and dendritic abnormalities in the neocortex of Alzheimer patients and examined the extent to which these structural alterations correlate with the severity of cognitive impairment in AD. Quantitative neuroanatomical data were obtained from immunofluorescence-labeled specimens using a laser-scanning confocal microscope, computer-assisted image processing and serial section reconstruction techniques. We found that the AD cases showed a 34% loss in the number of presynaptic terminals per 100 square (sq) microns, many of which showed structural abnormalities. The AD neuropil had an average of 10 +/- 7 dendritic threads per 1,000 sq microns, with the average thread measuring 2 sq microns. Severe AD cases had thicker threads compared with mild to moderate AD cases. Three-dimensional analysis showed clustering of synapses around threads, as well as presynaptic boutons apposed to dendritic neuropil threads. Statistical analysis showed that the strongest correlation was between synapse density and Blessed score of cognitive impairment. Thread counts did not correlate with either but were correlated with tangle counts. Stepwise multiple regression analysis showed that tangle counts, but not threads, strengthened the correlation between Blessed score and synapses. We conclude that synaptic damage may precede dendritic thread and tangle formation, and that threads do not necessarily induce synaptic pathology. Instead, dendrite sprouting in the denervated regions could be associated with increased accumulation of cytoskeletal proteins observed in the dendritic threads. 相似文献
84.
Abstract: This article integrates theory and research related to boundary ambiguity in parents of children with a chronic health condition. We propose that boundary ambiguity is a risk factor for psychological distress in these parents. Clinical applications and a case example highlight how boundary ambiguity can be assessed and managed in clinical settings by professionals working with parents with chronically ill children. Questions are provided for assessing boundary ambiguity in clinical and research settings, and implications for research are discussed. 相似文献
85.
The paper presents a survey of internet users und suppliers of psychotherapy and counselling. The survey based on a search for relevant homepages was carried out as an online questionnaire. Psychotherapy as such is not on offer in the internet in Austria in compliance with the law, but information on psychotherapy practice, first contacts and short-term counsellling is provided mainly via e-mail. There are some significant differences between patients and psychotherapists who use the internet and those who do not. The demographic data of patients using the internet are similar to those of internet users generally. Psychotherapists providing services on the internet tend to be older and more experienced than the average psychotherapist in private practice. 相似文献
86.
Brendan C Stack J Paul Hansen James M Ruda Jeff Jaglowski Joseph Shvidler Christopher S Hollenbeak 《Otolaryngology--head and neck surgery》2004,131(1):54-60
OBJECTIVE: A new class of carboxylic acids has tumoricidal activity for head and neck squamous cell cancer (HNSCC). Fusaric acid (FA) can chelate divalent cations, especially zinc, and inactivate zinc finger proteins involved in DNA repair and protein synthesis. METHODS: 2 squamous carcinoma lines were utilized for in vitro and in vivo portions of this study. Cell counting and flow cytometry were used to analyze cells in culture in treatment and control groups over 96 hours. HNSCC subcutaneous implants were created in treatment and control groups of BALB-c nude mice (N = 30). RESULTS: In vitro studies demonstrated significant changes in cell numbers and cell cycle. In vivo studies of daily intralesional therapy for 1 month also showed reduced onset of growth and overall growth compared to controls. CONCLUSION: FA appears to have a tumoristatic/tumoricidal effect on HNSCC. Further nude mice studies are needed to optimize dosing and administration regimens for FA in anticipation of clinical trials. 相似文献
87.
Francoise Mouchet Valérie Hansen Inge Van Herreweghe Olivier Vandenberg Régine Van Hesse Michèle Gérard Michèle Toppet Maryse Wanlin Véronique Toppet Georges Casimir Dominique Haumont Jack Levy 《Infection control and hospital epidemiology》2004,25(12):1062-1066
OBJECTIVE: To assess the extent of nosocomial transmission of tuberculosis among infants, family members, and healthcare workers (HCWs) who were exposed to a 29-week-old premature infant with congenital tuberculosis, diagnosed at 102 days of age. DESIGN: A prospective exposure investigation using tuberculin skin test (IST conversion was conducted. Contacts underwent two skin tests 10 to 12 weeks apart. Clinical examination and chest radiographs were performed to rule out disease. Isoniazid prophylaxis was administered to exposed infants at higher risk. SETTING: A neonatal intensive care unit in an urban hospital in Brussels, Belgium. PARTICIPANTS: Ninety-seven infants, 139 HCWs, and 180 visitors. RESULTS: Newly positive TST results occurred in HCWs who had been in close contact with the infant. Six (19%) of 32 primary care nurses and physicians had TST conversions and received treatment. Among the 97 exposed infants, 85 were screened and 34 were identified as at higher risk of infection. Of these, 27 received preventive isoniazid. None of the infants and none of the 93 other infants' family members evaluated were infected. CONCLUSIONS: Congenital tuberculosis in an infant poses a risk for nosocomial transmission to HCWs. Delayed diagnosis of this rare disease and close proximity are the most important factors related to transmission. 相似文献
88.
89.
The present study assessed neuropsychological functions related to attention, executive function and everyday memory in a group of men with a diagnosis of combat-related posttraumatic stress disorder (PTSD). Twenty Bosnian male combat veterans with a diagnosis of PTSD were tested using the Sustained Attention to Response Task, the Hayling Sentence Completion Test, the Trail Making Test, Rivermead Behavioral Memory Test and Wechsler Adult Intelligence Scale (verbal scales). Their performance was compared with age- and IQ-matched male war veterans with no PTSD. The study disclosed pervasive cognitive impairments with large effect sizes pertaining to attention, working memory, executive function, and memory. The effects did not appear to be attributable to alcohol abuse, loss of consciousness, or educational level. We speculate that, in the present group of combat veterans, PTSD was associated with dysfunction of a higher-level attentional resource which in turn affected the activity in other systems concerned with memory and thought. 相似文献
90.
Level of consciousness as a conditioning factor of F wave generation in stroke patients. 总被引:1,自引:0,他引:1
Elisabeth Chroni George Katsoulas Andreas A Argyriou George C Sakellaropoulos Panagiotis Polychronopoulos George Nikiforidis 《Clinical neurophysiology》2006,117(2):315-319
OBJECTIVE: The current study aimed to investigate whether the level of consciousness influenced the F wave generation, as an independent factor. METHODS: Forty three patients with acute stroke were divided according to their level of consciousness in two groups; to those with Glasgow scale (GCS) score 3-7 indicating coma (group I) and those with GCS score 8-15 (group II). A series of 40 electrical stimuli were delivered to the ulnar nerve bilaterally in order to obtain F waves. The following variables were estimated and then compared between groups: F persistence, F wave latency, amplitude and duration. All studies were performed within 3 days from the onset of the stroke symptoms. RESULTS: The main finding to emerge was the significantly reduced F wave persistence in the group of patients with low GCS score as opposed to patients allocated in the group with GCS score 8-15. This result is referred to F waves obtained from both the affected and unaffected limb. F wave minimum latency was also prolonged in the group with low GCS score, whilst the comparison of all other F wave variables revealed no significant differences between groups I and II. F wave persistence measurements did not differ between the affected and unaffected sides. Stroke location and type (ischemic or hemorrhagic) were not associated with alterations of F wave measurements. CONCLUSIONS: Our results on stroke patients suggest that generation of F waves, expressed by the F wave persistence is associated with the level of consciousness. SIGNIFICANCE: F wave study may be useful as an objective measure in documenting the severity of consciousness impairment. 相似文献