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BACKGROUND AND PURPOSE: Dotlike hemosiderin spots ongradient-echo T2(*)-weighted magnetic resonance imaging of the brain have been histologically diagnosed as old microbleeds associated with small vessel disease (SVD). The authors hypothesize that the presence of many dotHSs may be correlated with the fragility of small vessels and the recurrence of SVD, including lacunar infarction and deep intracerebral hemorrhage (ICH). METHODS: To investigate how dotHSs are related to past history of SVD, the number of subcortical or deep dotHSs was investigated in 146 patients with lacunar infarctions (95 men, 51 women, age 38 to 90 [66.6+/-9.4] years). They were divided into 2 subgroups according to history of deep ICHs or lacunar infarctions. The odds ratio (OR) for past history was estimated from logistic regression analyses with the number of subcortical or deep dotHSs as well as other factors. RESULTS: Of 146 patients with lacunar infarctions, 11 had past symptomatic ICHs and 19 had past symptomatic lacunar infarctions. An elevated rate of history of ICH was found for lacunar infarction patients with many deep dotHSs (>or=3; OR, 9.1; 95% confidence interval, 1.6-51, P=.015). However, history of lacunar infarction was not significantly associated with the number of subcortical or deep dotHSs. CONCLUSIONS: Our findings suggest that many deep dotHSs on T2(*)-weighted magnetic resonance imaging may be correlated with deep ICH-lacunar infarction type of SVD recurrence but not lacunar infarction-lacunar infarction type.  相似文献   
995.
Patients frequently present to the emergency room (ER) with mental status changes without obvious cause. The EEG is underused in this population. The authors investigated whether an abbreviated EEG (AbEEG) can be incorporated in the early evaluation of these patients to provide useful information. A 5-minute AbEEG was performed using a preformed electrode placement system on 25 patients who presented to the ER with mental status changes of unknown cause. AbEEG findings were categorized as normal, showing diffuse abnormalities, focal abnormalities, electrographic seizures, or uninterpretable. Using retrospective chart review, the authors determined if the cause of mental status change was a diffuse encephalopathy or a nonneurologic event (DENNE), a focal brain abnormality, nonconvulsive status epilepticus (NCSE), psychogenic, or unknown, and if particular AbEEG findings were associated with specific causes of altered sensorium. The AbEEG identified NCSE in two patients who presented with new-onset seizures. The presence of diffuse slowing on the AbEEG was highly suggestive of mental status changes due to DENNE. AbEEGs can be successfully incorporated in the early evaluation of patients who present to the ER with mental status changes of unknown cause and provide useful information in this setting.  相似文献   
996.
This breakout session at the Academic Emergency Medicine 2006 Consensus Conference examined how baseline overcrowding impedes the ability of emergency departments to respond to sudden, unexpected surges in demand for patient care. Differences between daily and catastrophic surge were discussed, and the need to invoke a hospital-wide response to surge was explored.  相似文献   
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This study investigates functional disability among some of the nation's most vulnerable older adults: rural Medicaid recipients. Data were provided by 221 older adults (mean age = 75.9 years; 82% women) who were receiving community-based long-term care services through Medicaid. Participants self-reported functional ability involving the completion of six basic activities of daily living (BADLs), three cognitive instrumental activities of daily living (IADLS), and four physical IADLs. Self-reports of depressed affect and the number of physical health conditions were also obtained. Path analysis was used to examine all of the associations among age, gender, number of chronic health conditions, depressed affect and functional disability. The tested model was significant [chi2 (DF = 3, n = 221) = 5.052, p = 0.168; TLI = 0.945; CFI = 0.992; RMSEA = 0.056] and explained 45.1% of the variance in BADL disability. Depressed affect significantly predicted disability in cognitive IADLs and physical IADLs, which predicted disability in BADLs. Age and gender had indirect effects on BADL, through their association with cognitive IADLs and physical IADLs. The number of chronic health conditions exerted both indirect and direct effects on BADL disability. Results are discussed within the context of the growing literature that suggests the importance of psychological variables as predictors of functional disability. Moreover, we discuss whether community-based long-term care is appropriate for older adults with high levels of functional disability.  相似文献   
999.
BACKGROUND AND PURPOSE: Following preoperative radiotherapy prior to ablative surgery of squamous epithelial cell carcinomas of the head and neck region, wound-healing disorders occur. Previous experimental studies showed altered expression of transforming growth factor-(TGF-)beta isoforms following surgery in irradiated graft beds. Altered levels of TGF-beta(1) are reported to promote fibrosis and to suppress vascularization during wound healing, whereas expression of TGF-beta receptor-III (TGF-betaR-III) is associated with vascularization. The aim of the study was to analyze the influence of anti-TGF-beta(1) treatment on TGF-betaR-III-associated vascularization in the transition area between irradiated graft bed and graft. MATERIAL AND METHODS: Wistar rats (male, weight 300-500 g) underwent preoperative irradiation of the head and neck region with 40 Gy (four fractions of 10 Gy each; n = 16 animals). A free myocutaneous gracilis flap taken from the groin was then transplanted to the neck in all rats. The time interval between operation and transplantation was 4 weeks. Eight animals received 1 micro g anti-TGF-beta(1) into the graft bed by intradermal injection on days 1-7 after surgery. On days 3, 7, 14, 28, 56, and 120, skin samples were taken from the transition area between transplant and graft bed and from the graft bed itself. Immunohistochemistry was performed using the ABC-POX method to analyze the TGF-betaR-III and E-selectin expression. Histomorphometry was performed to analyze the percentage and the area of positively stained vessels. RESULTS: A significantly higher expression of TGF-betaR-III was seen in the irradiated and anti-TGF-beta(1)-treated graft bed in comparison to the group receiving preoperative irradiation followed by transplantation alone. The percentage of TGF-betaR-III positively staining capillaries from the total amount of capillaries in the anti-TGF-beta(1)-treated graft bed was higher than in the group irradiated only. The total area of capillaries was also higher in the TGF-beta(1)-treated group. CONCLUSION: Neutralizing of TGF-beta(1) activity in irradiated tissue undergoing surgery leads to a higher expression of TGF-betaR-III and increased vascularization. TGF-betaR-III seems to be associated with newly formed blood vessels during neovascularization in wound healing.  相似文献   
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