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61.
Alcoholics admitted to the hospital solely for detoxication have been studied by flow cytometry to evaluate changes in the surface markers of peripheral blood leukocytes. As we have shown previously, such patients have an elevated percentage of CD8hl lymphocytes that are HLA DR+; we now demonstrate that they also have striking alterations in the quantitative relationships of the fine T-cell subsets. Both CD4+ and CD8hl lymphocytes have a sharply reduced percentage of the l -selectin+ CD45RA+ subset, increased percentages of the CD45RA-subsets, and several other fine subset alterations. The fine subset profile suggests, according to current correlations of phenotype and function, that both CD4+ suppressor inducer and CD4-dependent CD8+ suppressor effector cells are reduced, whereas other subsets, including CD8+ CTL or their precursors, are increased in relative percentages. Some of the phenotypic changes are reversible over the several days following withdrawal. In other results, the percentage of CD8hl lymphocytes expressing CD11b (β-integrin) is shown to be reciprocal with the percentage expressing l -selectin both in normals and alcoholics. However, the regression function of CD11b vs. l -selectin on CD8hl cells is different for the alcoholics than for the normals, indicating an abnormality in the regulation of the expression of these two adhesion markers. Taken together, this abnormality of adhesion molecules and the fine subset alterations previously described indicate widespread changes in the peripheral lymphocytes of currently drinking alcoholics. These changes suggest functional deficiencies that may include alterations of lymphocyte traffic and other adhesion-dependent functions, and a shift in the balance of regulatory interactions.  相似文献   
62.
63.
Job ending among youth and adults with severe mental illness   总被引:1,自引:0,他引:1  
This study examined job leaving over a 36-month period among 326 persons (74 youth and 252 adults) with severe mental illness who were participating in an urban vocational rehabilitation program. Data from 627 job endings indicated that younger clients displayed job-ending patterns that were different in some aspects from such patterns for nondisabled youth (such as displaying a lower average job tenure) yet similar to job-ending patterns for nonhandicapped youth in other ways (such as displaying a high frequency of job changing). Youth and their adult counterparts with mental illness displayed similar tenure on agency-sponsored placements but significantly different tenure on independent jobs. While adults held their independent jobs for an average of seven months, youth averaged only three months at competitive employment. Youth also were significantly more likely than adults to be fired from both placements and independent jobs. These findings and others are discussed in terms of their implications for development of public policy and service delivery models for providing on-going job support to youth and adults with severe psychiatric disabilities.  相似文献   
64.
Energy expenditure in leisure-time physical activity (LTPA) was measured using the Minnesota LTPA Questionnaire in 35- to 74-year-old black and white residents of Minneapolis-St. Paul, Minnesota. Estimates of the geometric mean LTPA energy expenditure were 129 and 204 kcal per day for black and white men (p<.05) and 91 and 123 kcal per day for black and white women (p<.05). The percentage of individuals expending 2000 kcal or more per week in LTPA was significantly lower in black men than white men (25 vs. 35%; p=.01) but was not different in black versus white women (18 vs. 17%). Although black men and women reported greater occupational physical activity than their white counterparts, LTPA and job activity were unrelated in all race and sex groups. In both races, LTPA energy expenditure declined with age. LTPA increased with level of formal education, and the largest LTPA difference between blacks and whites was observed in those who had a high-school diploma or less. Blacks had lower participation rates than whites in most of the individually assessed physical activities. Additional research is needed on the determinants and promoters of LTPA in population subgroups.The research was funded by National Heart, Lung, and Blood Institute Research Grant R01 HL 23727 and National Research Award T32 HL 07328-10.  相似文献   
65.
Fifty-eight patients with severe thoracolumbar burst fractures were treated with bilateral transpedicular decompression, Harrington rod instrumentation, and spine fusion. Spinal realignment and stabilization was achieved by contoured dual Harrington distraction rods supplemented by segmental sublaminal wiring. Posterior element fractures were noted in 25 patients, 9 of whom had associated dural tears. Computed tomography was performed to assess the cross-sectional area of the spinal canal before surgery and after decompression. Patients at initial evaluation averaged greater than 67% spinal canal compromise. After surgery, successful decompression was accomplished in 57 patients. One patient required staged, anterior thoracoabdominal decompression and fibula strut grafting. At follow-up (average, 43 months; range, 25-70 months), neurologic improvement was found in 77% of the patients who initially presented with neurologic deficits. Thirty-four of 40 patients with incomplete paraplegia improved one or more subgroups on the Frankel scale. A solid fusion was attained in all 58 patients. No patient had a significant residual kyphotic deformity. Single-stage bilateral transpedicular decompression and dual Harrington rod instrumentation reliably provides decompression of the spinal canal and restores spinal alignment. The procedure allows early mobilization and provides an environment for solid fusion and maximum neurologic return.  相似文献   
66.
To better understand the impact of incident Parkinson's disease (PD) on the Veteran's Health Administration (VHA) and to develop methods applicable to future epidemiological research, we performed a medical record review study at a tertiary referral VHA medical center. Searching the local data base, we identified 782 veterans with diagnostic codes for PD or secondary parkinsonism (SP) between 1998 and 2000. Based on structured medical record review, a movement disorders specialist confirmed diagnoses for incident parkinsonism cases. Among the 782, 191 incident parkinsonism cases were identified (100 PD, 75 SP, and 16 Parkinson's Plus). Incident PD cases were older at diagnosis (74.5 vs. 70.4 yr; P < 0.05) and more likely to be white (81% vs. 62; P < 0.07) than incident SP cases. Diagnostic codes were insufficient to distinguish between incident PD and SP (positive predictive value, 57% and 39%, respectively), and VHA sources failed to identify 21% of confirmed deaths among the incident PD cohort by November 2004. Although the large number of incident cases identified suggests PD is an important cause of disability among elderly VHA users, observed limitations of VHA sources for identifying incident PD cases and determining their vital status should be considered when designing future studies.  相似文献   
67.
The prevalence of selected illnesses and symptoms during 1977-85 was compared between 175 employees potentially exposed to the organophosphate insecticide chlorpyrifos and 335 matched controls with no history of exposure to organophosphates. Subjects were subdivided into three exposure intensity groups on the basis of job title and air monitoring data for dose response testing. This classification scheme was shown roughly to correlate with plasma cholinesterase inhibition in the workers. No statistically significant differences in illness or prevalence of symptoms were observed between the exposed and unexposed groups or among the three exposure subgroups. Potentially exposed employees did report symptoms of dizziness and of malaise and fatigue relatively more often than subjects from the comparison group; however, further analyses by exposure level, process area, or time did not support a relation with exposure. No cases of peripheral neuropathy were seen among the exposed workers. Although the sample size was small and the statistical power limited, the cumulative exposures likely to have been experienced by this workforce exceed those to be expected for individuals using the product as recommended. The absence of exposure related adverse effects, including neurological impairment, is reassuring.  相似文献   
68.
Specific binding of acidic isoferritins to erythroleukemia K562 cells   总被引:2,自引:0,他引:2  
An investigation of ferritin binding by human erythroleukemia K562 cells was prompted by recent studies suggesting that acidic isoferritins may act as regulators of granulopoiesis and hemopoiesis. Purified human heart and liver ferritins were labeled with iodine 125 and incubated with K562 cells at 37 degrees C. Specific uptake was calculated from the reduction in labeled ferritin binding in the presence of a 1000-fold excess of unlabeled ferritin. Specific uptake of 125I-labeled heart ferritin increased progressively, reaching a maximum after 2 to 3 hours' incubation, although nonspecific binding was too high to derive an affinity constant. There was no specific binding with 125I-labeled liver ferritin, and K562 cells bound neither 125I-labeled human serum albumin nor free 125I. Uptake of heart ferritin was negligible at 4 degrees C and was sharply reduced in the presence of 10% human plasma or fetal calf serum. There was no apparent relationship between the number of days of subculture and the level of uptake of acidic isoferritins by whole cells. These studies demonstrate a selective binding mechanism for acidic isoferritins on erythroleukemia cells and imply that these isoferritins have additional functions besides the storage of iron.  相似文献   
69.
Executive nurse managers, as well as other nurse managers, spend much time responding verbally to people. Whether or not their responses are effective in these situations remains an unexplored area in nursing administration. The author describes a research-based framework to analyse managerial actions. Five types of actions, three non-exploratory and two exploratory, were identified through previous research using Orlando's theory as the framework. Subsequent research suggests nurses prefer that their managers use exploratory action. The article contains discussion on how specific types of actions facilitate or thwart problem identification.  相似文献   
70.
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