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11.
We examined the efficacy of various irrigation solutions delivered through a power irrigator to remove bacteria from three different surfaces. Titanium, stainless-steel, and cortical bone surfaces were coated with three different bacterial species: Staphylococcus aureus, Pseudomonas aeruginosa, and Staphylococcus epidermidis. They were then irrigated with 1 L of fluid delivered by jet lavage. The fluids tested were normal saline and solutions of bacitracin, neomycin, and soap. One set of specimens was not irrigated, as a control. After irrigation, the specimens were sonicated to remove residual bacteria, and the sonicate was quantitatively cultured to allow evaluation of the amount of residual bacteria on the surface. The results showed that removal of bacteria reflects an interaction between bacterial species, surface characteristics, and irrigation solution. Fewer bacteria were present in all the irrigation groups than in the control. Soap solution was as good as or better than any other solution at removing all three types of bacteria from all three surfaces, although not all of the pairwise comparisons were statistically significant. There was a significant advantage to soap solution over antibiotic irrigant or saline alone in removing Staphylococcus epidermidis from metallic surfaces. The use of a soap solution for irrigation seems to improve the removal of some bacteria from some surfaces in this experimental model and may represent a better type of irrigation additive.  相似文献   
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The resolution of three 2-substituted derivatives of idazoxan is described. The enantiomers show large separations in activity in a variety of in vitro and in vivo tests, and the active isomers are all potent and selective antagonists at the alpha 2-adrenoreceptor. The significance of these results in relation to those published on the enantiomers of idazoxan and to those on optically active alpha 2-adrenoreceptor agonists is discussed.  相似文献   
16.
BACKGROUND: Pearly penile papules are angiofibromas found on the corona and sulcus of the glans penis. While these represent a benign condition, psychological and cosmetic concerns often prompt patients to seek therapeutic removal of these lesions. Multiple therapeutic modalities have been reported; however, use of CO2 laser has proven to be the most effective to date. OBJECTIVE: To demonstrate the efficacy of CO2 laser in treating pearly penile papules. METHODS: Case report. RESULTS: We report the successful treatment of pearly penile papules in an African American man with CO2 laser. CONCLUSION: The use of CO2 laser is an effective treatment for pearly penile papules. J. E. Lane, MD, C. M. Peterson, MD, and J. L. Ratz, MD have indicated no significant interest with commercial supporters.  相似文献   
17.
Although lesions of the pterygopalatine space are uncommon, there are instances in which this relatively inaccessible region must be entered for biopsy or excision of masses. Traditional open approaches to the pterygopalatine space, involving external or intraoral incisions, provide limited visualization and carry associated morbidities. The evolution and advancement of endoscopic sinus surgical technique in recent years has led to its application to anatomic areas outside the strict limits of the sinonasal cavities. Such minimally invasive approaches are safe, effective, and spare unnecessary discomfort to the patient. This article describes the authors' method for performing an endoscopic approach to the pterygopalatine space.  相似文献   
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Catecholamine (CA) release was measured in vivo in the monkey and cat visual cortices electrochemically. Stereate-modified, graphite-paste electrodes were used to monitor changes in norepinephrine and dopamine release. Micromolar changes in CA concentration were obtained by stimulation of the eye with nonspecific (strobe) or specific (oriented bars, radial gratings) stimuli. CA release depended on which eye was illuminated. Electrodes passed tangentially through the striate area recorded release following visual stimulation of one eye or the other in succession, and the shift in eye dominance occurred at about 500 microns intervals. The magnitude of CA release was highly correlated with the ocular dominance of neuronal activity measured with tungsten microelectrodes. Light-stimulated release was not recorded in monkey area V2, V4, or somatosensory area 1, but was recorded in cat V2, suggesting that the presence of LGN afferents is associated with CA release. Results are discussed in terms of the role of geniculate activity and the specific role of CAs in cortical information processing.  相似文献   
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In October 1982, a clinic was planned at The Royal Newcastle Hospital to review the usage of domiciliary oxygen that was funded by the Provision of Aids for Disabled Persons scheme in the Hunter Region of New South Wales. Patient review included an assessment of the indications for domiciliary oxygen, education in the use of oxygen, the efficiency of delivery arrangements and the transfer from cylinders to concentrators as indicated. Between January and June 1983, 111 patients who were receiving oxygen at home were reviewed: 84 (76%) of these patients had chronic obstructive pulmonary disease; their two-year survival was 80% (95% confidence interval, 69%-87%) and five-year survival was 36% (95% confidence interval, 25%-46%). In 66 (59%) patients, review led to a reduction in the usage of domiciliary oxygen which was estimated to save $40,000 each year in the Hunter Region. In the year from 1985-1986 the decrease in the usage of oxygen at home represented an actual cost saving of $60,000 for the region ($470 per person) which translated into a saving of $95,000 ($740 per person) when inflation was taken into account. If our experience is projected nation-wide, the potential exists for a considerable cost saving by means of programmes to rationalize the use of domiciliary oxygen.  相似文献   
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Reports of plasma concentrations of antidepressants and their metabolites in patients with reduced renal function have been reviewed. The consequences of alteration of various pharmacokinetic factors on drug and metabolite concentrations have been compared with the observed data. Concentrations of drugs that are more than 95 percent metabolized are not altered by decreased renal function. Concentrations of drugs that are mostly excreted unchanged in urine are greatly increased in patients with reduced renal function. Concentrations of metabolites that account for 10 percent or more of the dose of a parent drug in urine are usually increased. In general, the observations can be explained without hypothesizing an effect of reduced renal function on clearance by metabolism.  相似文献   
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