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961.
BACKGROUND AND STUDY AIMS: Many lesions found during push enteroscopy to evaluate obscure gastrointestinal bleeding are within the reach of standard endoscopes. The aim of this study was to determine whether the rate of proximal lesions varies in relation to the type of obscure bleeding that is present. PATIENTS AND METHODS: A retrospective review of consecutive push enteroscopies carried out for obscure gastrointestinal bleeding between July 1996 and July 2000 was conducted. The patients were categorized into three groups: those with recurrent obscure/overt gastrointestinal bleeding; those with persistent obscure/overt gastrointestinal bleeding; and those with obscure/occult gastrointestinal bleeding. RESULTS: A total of 63 patients (24 men, 39 women; mean age 69.8) were included. Push enteroscopy examinations were conducted for recurrent obscure/overt bleeding in 32 patients; for persistent obscure/overt bleeding in 12 patients; and for obscure/occult bleeding in 19 patients. The overall diagnostic yield of push enteroscopy was 47 % (15 of 32) in the group with recurrent obscure/overt bleeding; 66 % (eight of 12) in the group with persistent obscure/overt bleeding; and 63 % (12 of 19) in the group with obscure/occult bleeding. However, when lesions within the reach of standard esophagogastroduodenoscopy (EGD) were excluded, the yield of push enteroscopy was slightly higher in the group with recurrent obscure/overt bleeding (41 %) than in the groups with persistent obscure/overt bleeding (33 %) and obscure/occult bleeding (26 %). There were fewer lesions within the reach of EGD in the group with recurrent obscure/overt bleeding than in the groups with persistent obscure/overt bleeding (6 % vs. 33 %; P < 0.05) or obscure/occult bleeding (6 % vs. 37 %; P < 0.05). CONCLUSIONS: Patients undergoing push enteroscopy for recurrent obscure/overt bleeding were significantly less likely to have lesions within the reach of EGD than patients with persistent obscure/overt bleeding or obscure/occult bleeding. Patients in the latter two groups would be able to undergo a repeat EGD examination before more intense evaluation with push enteroscopy or capsule endoscopy. 相似文献
962.
963.
Missonnier P Gold G Fazio-Costa L Michel JP Mulligan R Michon A Ibáñez V Giannakopoulos P 《The journals of gerontology. Series A, Biological sciences and medical sciences》2005,60(5):660-666
BACKGROUND: The conversion of mild cognitive impairment (MCI) to Alzheimer's disease is associated with substantial compromise of neocortical circuits subserving rapid cognitive functions such as working memory. Event-related potential (ERP) analysis is a powerful tool to identify early impairment of these circuits, yet research for an electrophysiological marker of cognitive deterioration in MCI is scarce. Using a "2-back" activation paradigm, we recently described an electrophysiological correlate of working memory activation (positive-negative working memory [PN(wm)] component) over parietal electrodes. METHODS: Ours was a longitudinal study of 24 MCI patients with ERP analysis at inclusion and neuropsychological follow-up after 1 year. We used ERP waveform subtraction analysis between the n-back and control tasks. Analysis of variance (ANOVA) was used to compare electroencephalograph latencies between progressive MCI (PMCI) and stable MCI (SMCI), and univariate regression was used to assess the relationship between neuropsychological measures at baseline and clinical outcome. RESULTS: Thirteen (54%) MCI patients showed PMCI, and 11 (46%) remained stable (SMCI). In SMCI, a PN(wm) component with significantly larger density compared to baseline was identified when subtracting the detection task for both the 1- and 2-back tasks. In contrast, in PMCI, the PN(wm) component was absent in both 1-back and 2-back conditions. Neuropsychological variables and n-back test performance at inclusion did not predict cognitive deterioration 1 year later. CONCLUSIONS: In conjunction with recent functional imaging data, the present results support the notion of an early dysfunction of neural generators within the parietal cortex in MCI. They also reveal that the absence of the PN(wm) component may provide an easily applicable qualitative predictive marker of rapid cognitive deterioration in MCI. 相似文献
964.
Diet and retarded growth 总被引:1,自引:0,他引:1
The diets of 36 children below the third centile for height but with no organic disease were compared with the diets of a control group. In most cases retarded growth was associated with a long-continued deficiency in calorie intake. When the diets were reassessed about a year later the shortfall in calorie intake was significantly reduced. This improvement, which tended to be followed by an increase in the rate of growth in height, might have been due to alteration in the child's circumstances or improvement in the family attitudes and feeding habits or both. Advice given at the clinic is thought to have played a part in bringing these changes about. 相似文献
965.
966.
The oxygenation process of a human erythrocyte is monitored using a Raman microimaging technique. Raman images of the 1638 cm(-1) band are recorded in the oxygenated and deoxygenated state using only 120 s of laser exposure and approximately 1 mW of defocused laser power. The images show hemoglobin oxygenating and deoxygenating within the cell. Prolonged laser imaging exposure (<180 s) at low temperatures results in photoinduced and/or thermal degradation. The effect of thermal degradation is investigated by recording spectra of erythrocytes as a function of temperature between 4 and 52 degrees C. Five bands at 1396, 1365, 1248, 972, and 662 cm(-1) are identified as markers for heme aggregation. Raman images recorded of cells after prolonged laser exposure appear to show heme aggregation commencing in the middle and moving toward the periphery of the cell. UV-visible spectra of erythrocytes show the Soret band to be broader and red shifted (approximately 3 nm) at temperatures between 45 and 55 degrees indicative of excitonic interactions. It is postulated that the enhancement of the aggregation marker bands observed at 632.8-nm excitation results primarily from excitonic interactions between the aggregated hemes in response to protein denaturation. The results have important medical implications in detecting and monitoring heme aggregation associated with hemopathies such as sickle cell disease. 相似文献
967.
Glahn DC Bearden CE Caetano S Fonseca M Najt P Hunter K Pliszka SR Olvera RL Soares JC 《Bipolar disorders》2005,7(6):546-554
OBJECTIVES: Impaired verbal declarative memory has been proposed as a trait marker for adult bipolar disorder. However, similar impairments in juvenile-onset bipolar disorder have not been yet documented. Here, we assessed declarative memory in a large sample of clinically well-characterized children with bipolar disorder. METHODS: Forty-one children and adolescents with bipolar disorder [21 bipolar I disorder (BP-I), 10 bipolar II disorder (BP-II), and 10 bipolar disorder, not otherwise specified (BP-NOS)] and 17 demographically matched healthy participants completed a standardized learning and memory test. RESULTS: BP-I children recalled and recognized significantly fewer words than healthy subjects, whereas children with BP-II and BP-NOS did not differ from controls. However, individuals with BP-NOS made more perseverative errors and intrusions than the other groups. Severity of mood symptomatology was not associated with memory performance in any bipolar subtype. CONCLUSIONS: Findings suggest that declarative memory impairments in juvenile BP-I are similar to those seen in the adult form of the illness. These impairments do not appear to be secondary to clinical state; rather, they may reflect trait-related impairments. Distinct performance patterns in BP-I, BP-II, and BP-NOS suggest that the broadly defined phenotype is significantly heterogeneous, and may not be informative for pathogenetic investigations of bipolar disorder. 相似文献
968.
Papassotiropoulos A Lambert JC Wavrant-De Vrièze F Wollmer MA von der Kammer H Streffer JR Maddalena A Huynh KD Wolleb S Lutjohann D Schneider B Thal DR Grimaldi LM Tsolaki M Kapaki E Ravid R Konietzko U Hegi T Pasch T Jung H Braak H Amouyel P Rogaev EI Hardy J Hock C Nitsch RM 《Neuro-degenerative diseases》2005,2(5):233-241
Alzheimer's disease (AD) is the most common cause of dementia. It is characterized by beta-amyloid (A beta) plaques, neurofibrillary tangles and the degeneration of specifically vulnerable brain neurons. We observed high expression of the cholesterol 25-hydroxylase (CH25H) gene in specifically vulnerable brain regions of AD patients. CH25H maps to a region within 10q23 that has been previously linked to sporadic AD. Sequencing of the 5' region of CH25H revealed three common haplotypes, CH25Hchi2, CH25Hchi3 and CH25Hchi4; CSF levels of the cholesterol precursor lathosterol were higher in carriers of the CH25Hchi4 haplotype. In 1,282 patients with AD and 1,312 healthy control subjects from five independent populations, a common variation in the vicinity of CH25H was significantly associated with the risk for sporadic AD (p = 0.006). Quantitative neuropathology of brains from elderly non-demented subjects showed brain A beta deposits in carriers of CH25Hchi4 and CH25Hchi3 haplotypes, whereas no A beta deposits were present in CH25Hchi2 carriers. Together, these results are compatible with a role of CH25Hchi4 as a putative susceptibility factor for sporadic AD; they may explain part of the linkage of chromosome 10 markers with sporadic AD, and they suggest the possibility that CH25H polymorphisms are associated with different rates of brain A beta deposition. 相似文献
969.
970.
Boszczowski I Nicoletti C Puccini DM Pinheiro M Soares RE Van der Heijden IM Costa SF Barone AA Levin AS 《The Pediatric infectious disease journal》2005,24(7):648-650
Four cases of infection by extended spectrum beta-lactamase-producing Klebsiella pneumoniae occurred in the neonatal intensive care unit. Isolation, empiric therapy change and education produced no effect. Newborn weekly colonization rates were 0-18.7%. One health care worker with onychomycosis was positive for extended spectrum beta-lactamase-producing K. pneumoniae. Isolates were identical by molecular typing. Outbreak was controlled when the health care worker was excluded from the neonatal intensive care unit. 相似文献