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991.
992.
Blood gas analyzers serve a critical role in providing information that reflects patient homeostasis. This study was undertaken to evaluate the accuracy, reliability, consistency, and bias of the Radiometer ABL-70 point of care blood gas analyzer. Thirty samples were gathered for analysis of pH, pCO2, pO2, sodium, potassium, sodium bicarbonate, and base excess. Twenty-nine samples were gathered for hematocrit, 31 for ionized calcium, and 33 for venous pO2 and saturations. The data were compared with the Gem-Premier point of care analyzer and the hospital blood gas machine and electrolyte analyzer. There was statistical significance between the pH, pCO2, sodium, potassium, calcium, hematocrit, and venous pO2 and saturations when comparing the ABL-70 with the Gem-Premier. When comparing the ABL-70 with the Corning 278/270 blood gas machine/Co-Ox, the AVL-9180, and the Dimension XL, there was statistical significance seen between the pH, pCO2, pO2, sodium, calcium, hematocrit, and base excess. Although this statistical significance was observed between the ABL-70 and the other analyzers, the significance was not of clinical importance. The ABL-70 demonstrated acceptable accuracy, reliability, consistency, and bias. 相似文献
993.
High-dose ibuprofen for reduction of striatal infarcts during middle cerebral artery occlusion in rats 总被引:10,自引:0,他引:10
Antezana DF Clatterbuck RE Alkayed NJ Murphy SJ Anderson LG Frazier J Hurn PD Traystman RJ Tamargo RJ 《Journal of neurosurgery》2003,98(4):860-866
OBJECT: Ibuprofen is an antiinflammatory drug that disrupts leukocyte-endothelial cell interactions by limiting expression of endothelial adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1), also known as CD54. The authors hypothesized that ibuprofen could reduce the size of the infarct associated with transient focal ischemia by inhibition of ICAM-1 expression, and they evaluated its effects in rats treated with middle cerebral artery (MCA) occlusion. Ibuprofen treatment was compared with mild systemic hypothermia, which is known to be neuroprotective and is commonly used during neurosurgical procedures. METHODS: The maximum ibuprofen dose (240 mg/kg/day) that could be tolerated with no systemic toxicity was established in the initial experiments. In the efficacy experiment, rats were pretreated with vehicle, ibuprofen, or hypothermia (33 degrees C) prior to 2 hours of MCA occlusion; then their brains were harvested at 24 hours of reperfusion for histological studies. End-ischemic cerebral blood flow (CBF) was evaluated using [14C]iodoantipyrine autoradiography in additional cohorts. Expression of ICAM-1 within ischemic compared with nonischemic caudate nucleus and putamen (striatum) or cortex was evaluated using immunohistochemical studies. Compared with vehicle treatment, ibuprofen produced a 46.2% reduction (p = 0.01) in striatal infarcts, which was comparable to hypothermia (48.7% reduction, p = 0.02). Ibuprofen did not alter end-ischemic CBF in any region studied, and the ibuprofen treatment group had the lowest proportion of animals with marked ICAM-1 staining. CONCLUSIONS: Ibuprofen given in maximum tolerated doses reduces the striatal infarct size after focal cerebral ischemia. The neuroprotective mechanism does not work through preservation of intraischemic CBF and is consistent with inhibition of ICAM-1 expression; however, at the doses used in this study, other effects of ibuprofen on platelet and endothelial function are possible. 相似文献
994.
995.
Androgen and estrogen receptors in the human corpus cavernosum penis: immunohistochemical and cell culture results 总被引:4,自引:1,他引:3
Schultheiss D Badalyan R Pilatz A Gabouev AI Schlote N Wefer J von Wasielewski R Mertsching H Sohn M Stief CG Jonas U 《World journal of urology》2003,21(5):320-324
Despite the central and peripheral effects of androgens on the nervous system, the local effects of androgens in the corpus cavernosum penis and their importance for erectile function is still unclear. In this study corpus cavernosum biopsies of eight adult potent patients, aged 19–63 years, undergoing penile deviation surgery (group A) and 12 patients undergoing male-to-female transsexual surgery (group B) were immunostained for nuclear androgen and estrogen-alpha receptors. Additionally, primary corpus cavernosum endothelial cell cultures were obtained from six transsexual patients and exposed to testosterone, dihydrotestosterone, estradiol and progesterone likewise for 7 days. Total cell count was performed and cell metabolic activity was measured by a tetrazolium salt-based assay. Androgen and estrogen-alpha receptors were detected in stromal as well as in endothelial cells. Of all cell nuclei, 74.9% (SD 16.4) in group A and 63.5% (SD 17.1) in group B were positively stained for androgen receptors. The respective percentage of estrogen receptors was 11% (SD 9.5) and 21.2% (SD 12.6). An age-dependent difference in receptor distribution was not observed in either group. In the cell culture system only cultures exposed to testosterone and dihydrotestosterone showed a dose-dependent increase of cell metabolic activity compared to the cultures supplemented with estradiol and progesterone. The significant and age-independent high androgen and low estrogen-alpha receptor distribution found in both groups suggests a possible peripheral effect of androgens at the level of the corpus cavernosum penis in adult humans. This is supported by the observed effect of testosterone and dihydrotestosterone on cell count and endothelial cell metabolism in our cell culture system. The role of estrogens remains unclear. 相似文献
996.
Rafael Matesanz 《Transplant international》2003,16(10):736-741
Spain is the only existing example of a large country (40 million inhabitants) with a continuous increase in cadaveric organ donation for a period of over 10 years, and, in parallel, with an increase in the overall number of solid organ transplantations. A proactive donor detection program performed by well-trained transplant coordinators, the introduction of systematic death audits in the hospitals combined with a positive social atmosphere, adequate management of mass media relations, and adequate economic reimbursement for the hospitals accounted for this success. Some regions of Italy, for example Tuscany, have successfully adapted this approach with excellent results. We can conclude that the "Spanish Model" can be partially or totally adapted to other countries or regions if basic conditions are guaranteed. An adequate and careful study of the local characteristics that influence organ donation directly or incirectly should be carried out before planning any specific action to improve organ donor rates. 相似文献
997.
Mateo R Beyer WN Spann JW Hoffman DJ Ramis A 《Journal of toxicology and environmental health. Part A》2003,66(14):1371-1389
Some of the adverse effects of lead (Pb) may be associated with oxidative damage of lipids, proteins, or DNA. In a previous study a linkage was observed between the susceptibilities of waterfowl species to Pb poisoning with oxidative stress. To investigate this relationship among the individuals of a single species, for 3 wk 4 groups of 12 mallards were fed diets containing high or low levels of vitamin E (20 or 220 UI/kg) and high or low levels of Pb (0 or 2 g/kg). During the first week of Pb exposure, mallards developed hemolytic anemia, and during the second week, signs of neurological impairment. Histological findings in the Pb-exposed mallards were hemosiderosis, demyelinization of sciatic and brachial nerves, and tumefaction of renal tubular epithelium with the presence of intranuclear inclusion bodies. Lipid peroxidation increased with Pb exposure in blood, liver, bile, and brain, but decreased in nerves. Glutathione (GSH) increased with Pb exposure in liver and bile, and its oxidized/reduced ratio only increased in bile. Pb exposure inhibited GSH peroxidase activity (GPX) in plasma, liver, and brain, and decreased protein thiols (PSH) in blood and liver. Vitamin E resulted in significantly lower lipid peroxidation in nerves of control birds relative to unsupplemented controls, but did not alleviate any sign of lead posioning. Pb-induced pathological changes associated with hepatic and nervous functions were significantly correlated with lower GPX activity and PSH concentrations in these tissues rather than lipid peroxidation. Data suggest that inhibition of antioxidant enzymes and interaction with sulfhydryl groups of proteins may play a more important role in Pb poisoning of waterfowl than lipid peroxidation. 相似文献
998.
Management of acute ulcerative and necrotising herpes simplex and zoster keratitis with amniotic membrane transplantation 总被引:4,自引:0,他引:4 下载免费PDF全文
Heiligenhaus A Li H Hernandez Galindo EE Koch JM Steuhl KP Meller D 《The British journal of ophthalmology》2003,87(10):1215-1219
AIM: To report promoted healing of acute ulcerative and necrotising herpetic keratitis after amniotic membrane transplantation (AMT). METHODS: Retrospective, non-comparative case series of seven patients with acute ulcerative and necrotising herpetic stromal keratitis. Single or multilayer AMT with epithelial side facing up was performed. The main outcome measures were wound healing of the corneal ulcers and decrease of stromal inflammation. RESULTS: The mean follow up was 10.7 (SEM 1.4) months (range 5-15 months). AMT was performed once in five cases, and twice in further two. Improvement of stromal inflammation was noted within 16.4 (2.5) days (range 7-28 days). Epithelial defects healed within a mean of 17 (2.7) days (range 7-28 days). Vision improved in all but two patients. No serious side effects occurred during the follow up. CONCLUSIONS: Although performed in an uncontrolled and non-randomised series of patients, these findings indicate that the AMT shows promise in selected cases for the restoration of ocular surface integrity, reduction of stromal inflammation, and improvement of vision in acute ulcerative and necrotising herpetic keratitis. 相似文献
999.
1000.
Loewenstein A Malach R Goldstein M Leibovitch I Barak A Baruch E Alster Y Rafaeli O Avni I Yassur Y 《Ophthalmology》2003,110(5):966-970
PURPOSE: To investigate a method that uses hyperacuity, the Macular Computerized Psychophysical Test (MCPT), to evaluate the central macular visual field in patients with age-related macular degeneration (AMD). DESIGN: Prospective case-control study of a diagnostic test. PARTICIPANTS AND CONTROLS: One hundred eight eyes of 108 Patients with AMD and 51 eyes of 51 age-matched patients with no retinal disease. Patients with AMD included 32 (30%) patients with choroidal neovascularization (CNV), 23 (21%) with geographic atrophy (GA), 35 (32%) with AMD with high-risk characteristics (HRC), and 18 (17%) with early AMD with non-HRC. TESTING: Each subject underwent the MCPT, in which a virtual line composed of dots (white dots on a black background, maximal contrast) is flashed across different macular loci to a perifoveal radius of 7 degrees. Patients' responses were recorded and automatically analyzed using a specific algorithm developed before the onset of the study. All patients also underwent a supervised Amsler grid examination on the encounter before or after the MCPT in random order. MAIN OUTCOME MEASURES: Distortion, scotoma, or blurring perceived by the patient after a swift change of fixation was considered positive on the MCPT. Any perception of distortion, scotoma, or blurring was considered positive on the Amsler grid. RESULTS: Of the 32 patients with CNV, 30 (94%) were found positive on the MCPT and 11 (34%) were found positive on the Amsler grid. Of the 23 GA patients, 21 (91%) were found positive on the MCPT and 7 (30%) were found positive on the Amsler grid. Of the 35 HRC patients, 28 (80%) were found positive on the MCPT and 3 (9%) were found positive on the Amsler grid, and of the 18 early AMD with non-HRC patients, 8 (44%) were found positive on the MCPT and 3 (17%) were found positive on the Amsler grid. Of the 51 controls, 3 (6%) were positive on the MCPT and 1 (2%) was positive on the Amsler grid. CONCLUSIONS: The MCPT was superior to the Amsler grid in detecting AMD-related lesions in this cohort. Studies are underway to determine whether the MCPT is feasible for home monitoring to provide early detection of progression to CNV. 相似文献