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41.
42.
Markus Donix Bettina Beuthien-Baumann Rüdiger von Kummer Georg Gahn Fatima Thomas Vjera Holthoff 《Journal of clinical neuroscience》2007,14(6):601-603
Waldenstrom's macroglobulinemia (WM) is an uncommon low-grade lymphoma. Cognitive impairment due to central nervous system infiltration by lymphoplasmocytoid cells (Bing-Neel syndrome) has been rarely reported. We describe a 54-year-old man who was referred to a memory disorder clinic with a 9-month history of clinically obvious nonfluent aphasia and WM. He underwent extensive neuropsychological testing, clinical examination and structural and functional brain imaging. The diagnosis of the diffuse form of the Bing-Neel syndrome was supported by abnormal lymphoid cells found in the cerebrospinal fluid. Structural and functional brain imaging revealed impairment of brain areas due to white matter changes and subsequent functional deficits mimicking the neuropsychological syndrome encountered in progressive nonfluent aphasia. The diffuse form of Bing-Neel syndrome and neurological deficits are assumed to be the result of leptomeningeal infiltration by malignant cells and/or neoplastic vascular obstruction. 相似文献
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Birgit Herting MD Bettina Beuthien‐Baumann MD Katrin Pöttrich PhD Markus Donix MD Antje Triemer PhD Johannes B. Lampe MD Rüdiger von Kummer MD Karl Herholz MD Heinz Reichmann MD Vjera A. Holthoff MD 《Movement disorders》2007,22(4):490-497
Depressive symptoms are common in patients with neurodegenerative disorders. Imaging studies suggest that a disruption of frontal-subcortical pathways may underlie depression associated with basal ganglia disease. This pilot study tested the hypothesis that frontal dysfunction contributes to depression associated with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Depressed patients with MSA (n = 11), PSP (n = 9), and age-matched controls (n = 25) underwent measures of cerebral glucose metabolism applying positron emission tomography with (18)F-fluorodeoxyglucose. Regional metabolism in the patient groups was compared to the normal subjects using the voxel-based statistical parametric mapping. Depressive symptom severity (Hamilton Depression Rating) and degree of locomotor disability (Hoehn & Yahr) were assessed in the patient groups. The association between prefrontal metabolism and the occurrence of depressive symptoms and the degree of locomotor disability was investigated. When compared to controls, MSA patients revealed significant metabolic decreases in bilateral frontal, parietal, and cerebellar cortex and in the left putamen. In PSP patients, significant hypometabolism was demonstrated in bilateral frontal cortex, right thalamus, and midbrain. Depression severity but not the patients' functional condition was significantly associated with dorsolateral prefrontal glucose metabolism in both patient groups. The findings of this pilot study support the hypothesis that depressive symptoms in MSA and PSP are associated with prefrontal dysfunction. 相似文献
45.
Positive, negative, unknown: assumptions of HIV status among HIV-positive men who have sex with men.
Jeffrey T Parsons Joseph Severino Jose Nanin Joseph C Punzalan Kirk von Sternberg Whitney Missildine David Frost 《AIDS education and prevention》2006,18(2):139-149
Serosorting (i.e., engaging in unprotected sex with partners known to be of the same serostatus) can be a difficult process for men who have sex with men (MSM) who frequently make assumptions about their partners' serostatus. This process can be further complicated by a partner's dishonesty as well as other individual and contextual factors. The present study specifically examined how assumptions of serostatus made about unknown serostatus partners impact on the sexual behavior of 110 alcohol-abusing HIV-positive MSM. Although previous research has shown that HIV-positive MSM are more likely to serosort with other known HIV-positive men than with known HIV-negative men, our data suggest that unprotected sex behavior may not be specifically driven by whether or not they made assumptions of seroconcordance or serodiscordance. The types of assumptions these HIV-positive MSM made about their unknown status sexual partners and the basis for such assumptions were also examined. Owing to the ambiguities involved in assumptions of a partner's serostatus in sexual encounters, the 'unknown status' partner category is analytically distinct from 'known status' categories, and needs to be more fully explored because of its impact on perceived serosorting, rather than actual serosorting, among HIV-positive men. 相似文献
46.
K Radon S Huemmer H Dressel D Windstetter G Weinmayr S Weiland E Riu C Vogelberg W Leupold E von Mutius M Goldberg D Nowak 《The European respiratory journal》2006,27(4):774-778
Existing guidelines advise adolescents with asthma and allergies against high-risk occupations. The aim of the current authors' analyses was to investigate the resulting self-selection in a prospective cohort study. The participants of Phase II of the International Study of Asthma and Allergies in Childhood in Germany (aged 9-11 yrs at baseline) were re-contacted after 7 yrs (response rate was 77%) and were asked to complete a questionnaire, which included items on atopic diseases. The subjects were also asked about the type of job they would like to have in the future (preferred job choice). Exposure to agents with potential asthma risk was evaluated using a job exposure matrix. The analyses were restricted to those in school-based vocational training programmes without occupational exposures. A total of 33% of subjects chose jobs with high asthma risk, 23% selected low asthma risk jobs and the remaining adolescents indicated jobs without known asthma risk (reference category). There were no statistically significant associations between asthma, allergic rhinitis or atopic dermatitis and selecting jobs with asthma risk. Participants with allergic rhinitis tended to select high risk jobs less frequently. In conclusion, self-selection into low risk jobs seems to play a minor role in teenagers with asthma or allergies. 相似文献
47.
Andr ia Kist Fernandes Felipe Mallmann Ana Maria Pasquali Steinhorst Fernando Lopes Nogueira Eduardo Mü ller vila Dumitriu Zunino Saucedo Francisco Juchem Machado Marcelo Greg rio Raymundi S rgio Saldanha Menna Barreto Paulo de Tarso Roth Dalcin 《The Journal of asthma》2003,40(6):683-690
Asthma patients that depend on emergency department (ED) services are generally considered to have extremely poor disease control and prognosis. It is important to identify characteristics related to poor disease control and frequent visits to the ED to apply appropriate clinical management. This study comprised a cross-sectional survey of consecutive patients with asthma exacerbation (age ≥12 years) presenting at the adult ED of a large, tertiary care, university-affiliated hospital over a 2-month period. The frequent visitors (FV) were defined by ≥3 visits to the ED in the preceding year, and the occasional visitors (OV) by ≤2 visits. Eighty-six patients (61 females and 25 males) were included in the study (mean age 38 ± 18 years). Of these patients, 51.2% were FV and 48.8% were OV. Sixty-nine percent had annual income lower than A$3000 and 66.3% had ≤8 years of the formal education. Only 18.6% had used inhaled corticosteroids, 79.1% identified the asthma attack severity, 70.9% increased or initiated inhaled β-agonist, 20.9% increased or initiated steroid therapy, and 55.8% had an asthma action plan for attack. The number of hospital admissions in past year (OR 4.3, P = .02), use of home nebulizer (OR 3.6, P = .05) and the lack of a written asthma action plan (OR 3.3, P = .03) were independently associated with frequent visits to the ED. We conclude that a substantial proportion of the patients that visit the ED are FV. These patients are more likely to have hospital admission in the past year, to use a home nebulizer, and to lack a written asthma action plan. They should be considered the most important target for asthma education. 相似文献
48.
49.
Macrophage response to microtextured silicone 总被引:1,自引:0,他引:1
Seven different silicone surface textures were tested for effect on macrophage spreading and metabolic activity in vitro. Variables of the textured arrays that could modify spreading were determined to be the size, spacing between, depth, density, and orientation of the individual surface events and the roughness of the surfaces. Cells were influenced by the size of the events and the roughness of the surfaces more than any other variables. Cell morphology data, surface area and perimeter, could be divided into discrete regions that correlated well with the size of the events. Cell dimensions on 5μm textures were smallest while those on smooth silicone and glass surfaces were the largest. Surface texture events may be modifying contact guidance of the cells or interacting with specific transmembrane proteins to alter cell shape and function. The mitochondrial activity of cells attached to the textured silicones was determined by measuring the amount of reduced MTT directly through live cells. Cells on polystyrene (PS), 5VP and 8VP textures were metabolically more active than cells on the other textures. PMA was used to stimulate cells on the various textures. PMA-stimulated cells, on the smaller textures, 2VP, 5VP and 5CP, were less active than test cells that were not stimulated. The inability of PMA to stimulate these cells may be due to a structural alteration of protein kinase C. An hypothesis is introduced that includes a possible mechanism of how a micrometre-sized surface texture could modify cell function. 相似文献
50.
Seth M Brown Babak Sadoughi Hernando Cuellar Ron von Jako Marvin P Fried 《Otolaryngology--head and neck surgery》2007,136(2):268-273
OBJECTIVE: One of the main limitations of image-guided surgery is that navigation relies on the use of a CT scan obtained before surgery and is unable to be updated during the procedure. A software addition has been developed to allow reconstruction of CT-like images from a series of fluoroscopic scans and integrate these into an image-guided system (GE Healthcare Surgical Navigation, Lawrence, MA). We report our initial experience with a series of patients undergoing intraoperative fluoroscopic navigation in sinus surgery. STUDY DESIGN AND SETTINGS: After institutional review board clearance, we prospectively studied 14 consecutive patients undergoing image-guided sinus surgery with the use of intraoperative fluoroscopy. RESULTS: All patients had preoperative and postoperative fluoroscopic images reconstructed into CT-like images. By the conclusion of the study, images were adequate in quality and accurate navigation was achieved. CONCLUSION: Real-time image-guided sinus surgery using fluoroscopy is feasible. Future studies will need to focus on defining the procedures that could benefit, such as tumor resection, to enhance patient safety during these operations. 相似文献