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991.
Progressive multifocal leukoencephalopathy (PML) occurs in patients with profound immunosuppression. Although lesions are usually devoid of lymphoplasmocytic infiltrates, inflammatory forms of PML have been described, in both human immunodeficiency virus (HIV)-seropositive (HIV+) and-seronegative (HIV?) patients. In addition, PML has been shown to develop in HIV+ patients shortly after introduction of highly active antiretroviral therapy (HAART), despite a recovery of the immune system. Therefore, one could postulate that PML might arise in the context of an immune reconstitution syndrome. To examine the clinical and neuroradiological characteristics of inflammatory forms of PML, the authors performed a retrospective analysis of the patients seen at their institution since 1996 as well as a review of the literature. Of 39 HIV+ and HIV?PML patients, 5 (13%) presented with an inflammatory form of this disease. Two HIV+ patients developed PML soon after the onset of HAART, concomitant to immune recovery, as demonstrated by a decrease of HIV viral load (VL) and an increase of CD4+ T-cell count. Three patients (2 HIV+ and 1 HIV?) had signs of inflammation in the central nervous system (CNS) characterized by contrast-enhancing lesions on neuroimaging studies, and/or inflammatory infiltrates on brain biopsy. The presence of JC virus-specific cytotoxic T lymphocytes was demonstrated in 4/4 patients tested and the outcome was favorable in 3 of them. In agreement with previously published case reports, the data indicate that inflammatory reactions in PML are not infrequent, and that they are generally associated with a favorable prognosis. Therefore clinicians should not disregard the diagnosis of PML in presence of contrast-enhancing brain lesions, and should use caution before treating these immunosuppressed individuals with steroids.  相似文献   
992.
993.
The purpose of this study was to determine the effects of superior displacement of the hip center and changes in three prosthetic parameters (neck length, neck-stem angle, and anteversion angle) on the capacity of muscles to generate force and moment about the hip. A three-dimensional model that calculates the maximum isometric forces and moments generated by 25 muscles crossing the hip over a wide range of body positions was used to evaluate the effects of a 2 cm elevation of the hip center and changes in the prosthetic parameters. After superior displacement of the hip center, the neck length was increased from 0 to 3 cm, the neck-stem angle was varied between 110 and 150°, and the anteversion angle was varied between 0 and 40°. Our analysis showed that a 2 cm superior displacement of the hip center would decrease the moment-generating capacity of the four muscle groups studied (abductors, adductors, flexors, and extensors) if neck length were not increased to compensate for decreased muscle length. In the computer model of an adult man that we used, a 2 cm increase in neck length restored the moment-generating capacity of the muscles by increasing muscle length and force-generating capacity. However, a 3 cm increase in neck length increased passive muscle forces substantially, which potentially could limit joint motion. An increased neck-stem angle (i.e., a valgus neck) decreased the abduction moment arm but increased the moment-generating capacity of the other muscle groups. A change in the anteversion angle from 0 to 40° had a relatively small effect on the isometric moment-generating capacity of the muscles studied.  相似文献   
994.
One goal of supportive housing is to enlarge and improve the functioning of the social support networks of residents. The networks of a convenience sample of 42 residents were assessed using scales developed by Barrera. The size of the networks (11.5) was no larger than that reported for similar clients living in other types of community settings but the composition differed. Staff and co-residents appear to partially replace rather than add to family and friends. This is of concern because friends are uniquely important determinants of satisfaction. An association between perceived need for support and network size was also found. These findings suggest some positive influences but also raise questions about unintended negative consequences of living in artificially constructed social environments.When this project was undertaken, Dr. Goering, Janet Durbin, Bill Lancee and Taras Babiak were all members of the Social and Community Psychiatry Section, Clarke Institute. Robert Foster was Executive Director of Regeneration House, Inc., where Susan Boyles is Assistant Executive Director.  相似文献   
995.
Aspects of peri-operative management, amputation level and rehabilitation of the lower limb amputee are reported in the context of a review of a rehabilitation service for amputees which includes an integrated prosthetic service. Two hundred admissions were reviewed and some complex cases described. It is concluded that: a very close liaison between the surgeon and the rehabilitation team (ideally with pre-operative consultation) is in the patient's best interests; any person previously walking (or a potential walker) should be considered for a trial of prosthetic walking; an integrated prosthetic service enhances the efficiency of the rehabilitation service; and that modification of the current Artificial Limb Scheme to allow manufacture of first definitive limbs in prosthetic rehabilitation units would further enhance service to patients.  相似文献   
996.
Body composition of 24 rural Beninese women was assessed in a pre- and a postharvest season by using skinfold-thickness measurements, bioelectrical-impedance analysis (BIA), and deuterium oxide (D2O) dilution. Fat mass assessed by D2O dilution was 12.3 +/- 3.3 kg; by skinfold-thickness measurements, 13.8 +/- 3.3 kg; and by BIA, 14.1 +/- 2.9 kg. Fat mass assessed by D2O was significantly lower (P less than 0.05) than fat mass assessed by the other two methods. Body weight in the postharvest season was 0.8 +/- 1.6 kg higher (P less than 0.05) than during the preharvest season. All three methods demonstrated that there were no significant changes in fat mass but that fat-free mass increased significantly (P less than 0.05) from pre- to postharvest season.  相似文献   
997.
This study examined the variability in movement end points in a task in which human subjects reached to targets in different locations on a horizontal surface. The primary purpose was to determine whether patterns in the variable errors would reveal the nature and origin of the coordinate system in which the movements were planned. Six subjects moved a hand-held cursor on a digitizing tablet. Target and cursor positions were displayed on a computer screen, and vision of the hand and arm was blocked. The screen cursor was blanked during movement to prevent visual corrections. The paths of the movements were straight and thus directions were largely specified at the onset of movement. The velocity profiles were bell-shaped, and peak velocities and accelerations were scaled to target distance, implying that movement extent was also programmed in advance of the movement. The spatial distributions of movement end points were elliptical in shape. The major axes of these ellipses were systematically oriented in the direction of hand movement with respect to its initial position. This was true for both fast and slow movements, as well as for pointing movements involving rotations of the wrist joint. Using principal components analysis to compute the axes of these ellipses, we found that the eccentricity of the elliptical dispersions was uniformly greater for small than for large movements: variability along the axis of movement, representing extent variability, increased markedly but nonlinearly with distance. Variability perpendicular to the direction of movement, which results from directional errors, was generally smaller than extent variability, but it increased in proportion to the extent of the movement. Therefore, directional variability, in angular terms, was constant and independent of distance. Because the patterns of variability were similar for both slow and fast movements, as well as for movements involving different joints, we conclude that they result largely from errors in the planning process. We also argue that they cannot be simply explained as consequences of the inertial properties of the limb. Rather they provide evidence for an organizing mechanism that moves the limb along a straight path. We further conclude that reaching movements are planned in a hand-centered coordinate system, with direction and extent of hand movement as the planned parameters. Since the factors which influence directional variability are independent of those that influence extent errors, we propose that these two variables can be separately specified by the brain.  相似文献   
998.
999.
People undergoing medical procedures sometimes experience feelings that may influence the results. In this study, we explore the relationship between changes in mood state self-ratings and cerebral glucose metabolism during positron emission tomography (PET) in persons with age-associated memory impairment (mean age 59.4±9.8 years). Brain regions of interest involved in both mood and memory were examined. Mood ratings of increased boredom correlated significantly with mesial temporal and parietal asymmetry and decreased parietal metabolism. Mood ratings of increased fatigue correlated with basal ganglia asymmetry and the right basal ganglia and left mesial temporal metabolism. These findings suggest that subjective mood state changes during PET may influence metabolism in brain regions implicated in emotion and memory function in people with age-related memory complaints.  相似文献   
1000.
A 50-year old male presented with swollen right eyelids, bleeding per nostrils and a vague left post-auricular swelling for 4 months. Posterior rhinoscopy revealed one pinkish polypoidal mass in the posterior nare and roof of nasopharynx. FNAC from the post-auricular swelling suggested metastatic undifferentiated carcinoma. Incisional biopsy was done form the nasopharynx and histopathological examination proved it to be a malignant paraganglioma. The case is reported for its rarity.  相似文献   
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