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101.
The consequences of glucocorticoid receptor (GR) dysfunction for neuroimmunoendocrine responses to an inflammatory challenge were studied in transgenic mice expressing antisense RNA directed against the GR [GR-impaired (GR-i) mice]. Mice were implanted intraperitoneally with a biotelemetry transmitter to monitor body temperature and locomotion. GR-i mice showed decreased locomotion and body temperature during the dark phase of the diurnal cycle. Intraperitoneal administration of saline caused a rapid increase in body temperature in control mice, which was terminated within 90 min. In GR-i mice, however, body temperature remained elevated for about 6 h. Intraperitoneal injection of endotoxin (10 micrograms/mouse) produced a biphasic fever in control mice. However, in endotoxin-injected GR-i mice, body temperature was not significantly different from their saline-injected controls during the first 6 h. Body temperature then increased and remained elevated during the night period. Both strains showed hypolocomotion after endotoxin. In a second experiment, mice were injected intraperitoneally with saline or endotoxin and killed after 1, 3, 6 or 24 h. In GR-i mice, endotoxin caused an augmented rise in plasma ACTH, but not in corticosterone levels. The endotoxin-induced increase in serum levels of interleukin-1 beta and interleukin-6 was not different between the strains. However, whereas in control mice tumour necrosis factor-alpha levels were below detection at the time points studied, substantial levels of this cytokine were found in the serum of GR-i mice 1 h after endotoxin administration. It may be concluded that life-long impairment of GR evolves in aberrant physiological and humoral responses to an acute inflammatory challenge. These findings expand our understanding about the neuroendocrine and physiological disturbances associated with stress-related disorders.  相似文献   
102.
This paper presents topology-based methods to robustly extract, analyze, and track features defined as subsets of isosurfaces. First, we demonstrate how features identified by thresholding isosurfaces can be defined in terms of the Morse complex. Second, we present a specialized hierarchy that encodes the feature segmentation independent of the threshold while still providing a flexible multiresolution representation. Third, for a given parameter selection, we create detailed tracking graphs representing the complete evolution of all features in a combustion simulation over several hundred time steps. Finally, we discuss a user interface that correlates the tracking information with interactive rendering of the segmented isosurfaces enabling an in-depth analysis of the temporal behavior. We demonstrate our approach by analyzing three numerical simulations of lean hydrogen flames subject to different levels of turbulence. Due to their unstable nature, lean flames burn in cells separated by locally extinguished regions. The number, area, and evolution over time of these cells provide important insights into the impact of turbulence on the combustion process. Utilizing the hierarchy, we can perform an extensive parameter study without reprocessing the data for each set of parameters. The resulting statistics enable scientists to select appropriate parameters and provide insight into the sensitivity of the results with respect to the choice of parameters. Our method allows for the first time to quantitatively correlate the turbulence of the burning process with the distribution of burning regions, properly segmented and selected. In particular, our analysis shows that counterintuitively stronger turbulence leads to larger cell structures, which burn more intensely than expected. This behavior suggests that flames could be stabilized under much leaner conditions than previously anticipated.  相似文献   
103.
Although incivility has been identified as an important issue in workplaces, little research has focused on reducing incivility and improving employee outcomes. Health care workers (N = 1,173, Time 1; N = 907, Time 2) working in 41 units completed a survey of social relationships, burnout, turnover intention, attitudes, and management trust before and after a 6-month intervention, CREW (Civility, Respect, and Engagement at Work). Most measures significantly improved for the 8 intervention units, and these improvements were significantly greater than changes in the 33 contrast units. Specifically, significant interactions indicating greater improvements in the intervention groups than in the contrast groups were found for coworker civility, supervisor incivility, respect, cynicism, job satisfaction, management trust, and absences. Improvements in civility mediated improvements in attitudes. The results suggest that this employee-based civility intervention can improve collegiality and enhance health care provider outcomes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
104.
Archive cartography and archaeologist's sketches are invaluable resources when analysing a historic town or city. A virtual reconstruction of a city provides the user with the ability to navigate and explore an environment which no longer exists to obtain better insight into its design and purpose. However, the process of reconstructing the city from maps depicting features such as building footprints and roads can be labour intensive. In this paper we present techniques to aid in the semi-automatic extraction of building footprints from digital images of archive maps and sketches. Archive maps often exhibit problems in the form of inaccuracies and inconsistencies in scale which can lead to incorrect reconstructions. By aligning archive maps to accurate modern vector data one may reduce these problems. Furthermore, the efficiency of the footprint extraction methods may be improved by aligning either modern vector data or previously extracted footprints, since common elements can be identified between maps of differing time periods and only the difference between the two needs to be extracted. An evaluation of two alignment approaches is presented: using a linear affine transformation and a set of piecewise linear affine transformations.  相似文献   
105.
BACKGROUND: Right lower quadrant abdominal pain may pose a diagnostic problem in patients with cystic fibrosis. Abdominal ultrasound examination, used commonly in the diagnostic work-up, may reveal abnormalities of the appendix. However, interpretation of such findings is problematic, because the appearance of the gastrointestinal system during routine examination has not been documented in patients with cystic fibrosis. The purpose of this study was to investigate the findings during routine abdominal ultrasound scans in our cohort of patients with cystic fibrosis and in control subjects. METHODS: Abdominal ultrasound scans were performed prospectively during routine clinic visits in a cohort of patients with cystic fibrosis. RESULTS: Fifty patients aged 10+/-6 years, (range, 0.5-28 years) were examined; 45 had pancreatic insufficiency. Four patients (3 with pancreatic insufficiency) reported right lower quadrant pain at the time of the scan. According to standard ultrasound criteria, the appearance of the appendix was abnormal in 8 patients (16%), 6 had a mucoid appendix, and 2 had a pathologically thickened appendiceal wall. Only 1 of these 8 patients mentioned abdominal pain at the time of the study. Other incidental findings included gallstones (3 patients), intussusception (2 patients), and pancreatic cyst (1 patient). CONCLUSIONS: Abnormalities can be observed during routine abdominal ultrasonographic studies in cystic fibrosis. These findings may not be associated with abdominal pain; their clinical relevance needs further investigation.  相似文献   
106.
The use of near-infrared spectroscopy to measure noninvasively changes in the redox state of cerebral cytochrome oxidase in vivo is controversial. We therefore tested these measurements using a multiwavelength detector in the neonatal pig brain. Exchange transfusion with perfluorocarbons revealed that the spectrum of cytochrome oxidase in the near-infrared was identical in the neonatal pig, the adult rat, and in the purified enzyme. Under normoxic conditions, the neonatal pig brain contained 15 micromol/L deoxyhemoglobin, 29 micromol/L oxyhemoglobin, and 1.2 micromol/L oxidized cytochrome oxidase. The mitochondrial inhibitor cyanide was used to determine whether redox changes in cytochrome oxidase could be detected in the presence of the larger cerebral hemoglobin concentration. Addition of cyanide induced full reduction of cytochrome oxidase in both blooded and bloodless animals. In the blooded animals, subsequent anoxia caused large changes in hemoglobin oxygenation and concentration but did not affect the cytochrome oxidase near-infrared signal. Simultaneous blood oxygenation level-dependent magnetic resonance imaging measurements showed a good correlation with near-infrared measurements of deoxyhemoglobin concentration. Possible interference in the near-infrared measurements from light scattering changes was discounted by simultaneous measurements of the optical pathlength using the cerebral water absorbance as a standard chromophore. We conclude that, under these conditions, near-infrared spectroscopy can accurately measure changes in the cerebral cytochrome oxidase redox state.  相似文献   
107.
PATIENTS AND METHODS: The role of cerebral magnetic resonance imaging (MRI) in the diagnosis of growth hormone (GH) deficiency in children has been studied in 100 children. The diagnosis of GH deficiency was assessed at a mean age of 6.7 +/- 4.1 years: morphological abnormalities of the hypothalamic-pituitary (HP) region have been studied in three different groups: in the first group (70 cases), the neurohypophysis was present and normally located; in the second group (ten cases) it was missing; in the third group (20 cases) the neurohypophysis was ectopic (truncated stalk syndrome with ectopic neurohypophysis, small antehypophysis, thin or non-visualized stalk). RESULTS: In the majority of cases, children presenting with only one morphological abnormality of the HP region (ectopic neurohypophysis or small antehypophysis or non-visualized or thin stalk) had an isolated GH deficiency. When multiple morphological abnormalities were present, anterior pituitary deficiency was multiple in more than half the cases. Cerebral midline anomalies (above all Chiari I malformation and basipharyngeal canal) had been observed in 20% of the children presenting with GH deficiency. In the majority of cases (95%), these anomalies were associated with one or more abnormalities of the HP region. A familial case is reported: morphological anomalies of the HP region were different for both siblings. Genetic factors are evoked. CONCLUSION: The severity of the hormone deficiency is correlated to the ectopic location of the neurohypophysis, the thin appearance or non visibility of the pituitary stalk and the associated midline anomalies.  相似文献   
108.
109.
The process by which metamemory and academic causal attributions relate to recall was examined with hierarchical multiple regression analyses. Several alternative conceptualizations of metamemory were used: general metamemory unrelated to the specific task; task-specific metamemory; memory monitoring; and both general and task-specific attributions. In order to examine the additive benefits of strategy and monitoring instructions, 81 4th graders were assigned to 1 of 4 instructional conditions: Strategy Only, Process Monitoring Only, Strategy Plus Process Monitoring, or Practice-Control group. Regression analyses indicated that the relationships between metamemory and recall depended on how metamemory was assessed and on the timing of the child's engagement with the recall task. Whereas general metamemory was significantly related to recall on the posttest and near-transfer tasks, task-specific metamemory became more relevant for transfer. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
Among 267 patients with central nervous system infections, 43 patients (16.1%) suffered from purulent bacterial meningitis. An etiological agent was established in 15 cases (34.9%): Str. pneumoniae--9 cases, N. meningitidis--4 cases and Staph. aureus--2 cases. Most patients had severe course of the disease; lethality was 18.6%, the recovery with subsequent sequelae was noted in 11.6% cases, and 69.8% cases fully recovered. In two patients brain abscess and intracranial empyema, and persistent cerebral ischaemia were found, one of these patients died. Frequent use of antibiotics before hospitalization reduces the possibility of establishing the etiological agent. Bacterial infections of the central nervous system are still danger diseases producing high lethality and subsequent neurological sequelae.  相似文献   
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