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51.
Nakada  T; Kwee  IL; Griffey  BV; Griffey  RH 《Radiology》1988,168(3):823-825
Noninvasive metabolic magnetic resonance (MR) imaging reflecting glucose metabolism in the aldose-reductase-sorbitol (ARS) pathway was performed in the rabbit head; after administration of the fluorinated glucose analogue 3-fluoro-3-deoxy-D-glucose (3FD-glucose), fluorine-19 images were generated. Images of 3FD-glucose showed significant 3FD-glucose uptake by adipose tissue, indicating its buffering effects in case of excess loads of glucose. Images of 3-fluoro-3-deoxy-D-sorbitol (3FD-sorbitol) demonstrated the spatial distribution of aldose reductase activities and significant sorbitol accumulation in the lens. Images of 3-fluoro-3-deoxy-D-fructose (3FD-fructose) showed preferential uptake of fructose by muscle tissue. The extremely low toxicity of 3FD-glucose indicates promise for its clinical application in metabolic imaging.  相似文献   
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Purpose: To review literature specific to the use of AAC with adults who have severe aphasia. Method: The authors reviewed studies involving AAC interventions for adults with severe aphasia. Results: Published data support the use of aided and unaided AAC with adults with severe aphasia in controlled treatment contexts. Reported gains in communication typically have not generalized to everyday settings. Conclusions: The application of AAC with persons with severe aphasia must address factors potentially limiting treatment success outside of training environments.  相似文献   
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Methylation of TIMP3 in esophageal squamous cell carcinoma   总被引:1,自引:0,他引:1  
AIM: To measure the frequency of DNA methylation of the tissue inhibitor of metalloproteinase 3 (TIMP3) promoter and relate this to any change of gene expression in esophageal squamous cell carcinoma in patients from a region of high incidence in China. METHODS: Cancer cell lines were treated with or without the demethylating reagent 5-aza-2′-deoxycytidine. Methylation of the TIMP3 promoter was assessed in three regions by melt curve analysis and its expression was assessed by real-time RT-PCR. Tumors and proximal resection margins were obtained from 64 patients with esophageal squamous cell carcinoma from a region of high incidence in China. Methylation was assessed by melt curve analysis and expression by immunohistochemistry.
RESULTS: Methylation in one of the three promoter regions assessed correlated with gene silencing in esophageal cell lines. A degree of methylation of TIMP3 was found in only four esophageal squamous cell carcinomas, and partial loss of TIMP3 protein expression in just one.
CONCLUSION: Methylation and loss of expression of TIMP3 occurs infrequently in esophageal squamous cell carcinoma in a region of high incidence in China.  相似文献   
57.
In four healthy volunteers, we analyzed in detail the immediate in vivo effects on circulating neutrophils of subcutaneous administration of 300 micrograms of granulocyte colony-stimulating factor (G-CSF). Neutrophil activation was assessed by measurement of degranulation. Mobilization of secretory vesicles was shown by a decrease in leukocyte alkaline phosphatase content of the circulating neutrophils. Furthermore, shortly postinjection, Fc gamma RIII was found to be upregulated from an intracellular pool that we identified by immunoelectron microscopy as secretory vesicles. Intravascular release of specific granules was shown by increased plasma levels of lactoferrin and by upregulation of the expression of CD66b and CD11b on circulating neutrophils. Moreover, measurement of fourfold elevated plasma levels of elastase, bound to its physiologic inhibitor alpha 1- antitrypsin, indicated mobilization of azurophil granules. However, no expression of CD63, a marker of azurophil granules, was observed on circulating neutrophils. G-CSF--induced mobilization of secretory vesicles and specific granules could be mimicked in whole blood cultures in vitro, in contrast to release of azurophil granules. Therefore, we postulate that the most activated neutrophils leave the circulation, as observed shortly postinjection, and undergo subsequent stimulation in the endothelial microenvironment, resulting in mobilization of azurophil granules. Our data demonstrate that G-CSF should be regarded as a potent immediate activator of neutrophils in vivo.  相似文献   
58.
Drehobl MA  De Salvo MC  Lewis DE  Breen JD 《Chest》2005,128(4):2230-2237
BACKGROUND: Community-acquired pneumonia (CAP) is a major cause of morbidity and mortality worldwide. The inability or failure of many subjects to adhere to standard antibiotic regimens, which may last up to 10 days, results in suboptimal antibiotic treatment. Treatment with a single-dose antibiotic regimen may improve compliance with prescribed therapy. A novel microsphere formulation of azithromycin provides a single-dose regimen while maintaining tolerability. STUDY OBJECTIVE: To compare the efficacy and safety of a single 2.0-g dose of azithromycin microspheres to that of an extended-release formulation of clarithromycin (1.0 g/d for 7 days) for the treatment of adults with mild-to-moderate CAP. DESIGN: A phase III, multinational, multicenter, randomized, double-blind, double-dummy study, comparing single-dose azithromycin microspheres to extended-release clarithromycin, both administered orally. METHODS: Subjects with mild-to-moderate CAP (Fine class I and II) were included. The primary end point was clinical response at the test-of-cure (TOC) visit (days 14 to 21) in the clinical per protocol (CPP) population. The bacteriologic response at the TOC visit was assessed in subjects with a baseline pathogen. RESULTS: A total of 501 subjects were randomized, and 499 were treated. Clinical cure rates at the TOC visit in the CPP population were 92.6% (187 of 202 subjects) for azithromycin microspheres and 94.7% (198 of 209 subjects) for extended-release clarithromycin. Overall pathogen eradication rates were 91.8% (123 of 134 subjects) for azithromycin microspheres and 90.5% (153 of 169 subjects) for extended-release clarithromycin. Both agents were well tolerated. The incidence of treatment-related adverse events was 26.3% with azithromycin microspheres and 24.6% with extended-release clarithromycin. Most adverse events were mild to moderate in severity. CONCLUSION: A single 2.0-g dose of azithromycin microspheres was as effective and well tolerated as a 7-day course of extended-release clarithromycin in the treatment of adults with mild-to-moderate CAP.  相似文献   
59.
Inflammation is a basic pathological mechanism that underlies many diseases. An important component of the inflammatory response is the passage of plasma components and leukocytes from the blood vessel into the tissues. The endothelial monolayer lining blood vessels reacts to stimuli such as thrombin or vascular endothelial growth factor by changes in cell-cell junctions, an increase in permeability, and the leakage of plasma components into tissues. Other stimuli, such as tumor necrosis factor-alpha (TNF-alpha), are responsible for stimulating the transmigration of leukocytes. Here we show that angiopoietin-1, a cytokine essential in fetal angiogenesis, not only supports the localization of proteins such as platelet endothelial cell adhesion molecule-1 (PECAM-1) into junctions between endothelial cells and decreases the phosphorylation of PECAM-1 and vascular endothelial cadherin, but it also strengthens these junctions, as evidenced by a decrease in basal permeability and inhibition of permeability responses to thrombin and vascular endothelial growth factor. Furthermore, angiopoietin-1 inhibits TNF-alpha-stimulated leukocyte transmigration. Angiopoietin-1 may thus have a major role in maintaining the integrity of endothelial monolayers.  相似文献   
60.
STUDY OBJECTIVE: Elderly emergency department patients have complex medical needs and limited social support. A transitional model of care adapted from hospitals was tested for its effectiveness in the ED in reducing subsequent service use. METHODS: A randomized clinical trial was conducted at 2 urban, academically affiliated hospitals. Participants were 650 community-residing individuals 65 years or older who were discharged home after an ED visit. Main outcomes were service use rates, defined as repeat ED visits, hospitalizations, or nursing home admissions, and health care costs at 30 and 120 days. Intervention consisted of comprehensive geriatric assessment in the ED by an advanced practice nurse and subsequent referral to a community or social agency, primary care provider, and/or geriatric clinic for unmet health, social, and medical needs. Control group participants received usual and customary ED care. RESULTS: The intervention had no effect on overall service use rates at 30 or 120 days. However, the intervention was effective in lowering nursing home admissions at 30 days (0.7% versus 3%; odds ratio 0.21; 95% confidence interval [CI] 0.05 to 0.99) and in increasing patient satisfaction with ED discharge care (3.41 versus 3.03; mean difference 0.37; 95% CI 0.13 to 0.62). The intervention was more effective for high-risk than low-risk elders. CONCLUSION: An ED-based transitional model of care reduced subsequent nursing home admissions but did not decrease overall service use for older ED patients. Further studies are needed to determine the best models of care for this setting and for at-risk patients.  相似文献   
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