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51.
A new endoscopic method of measuring the cross-sectional area of a subglottic stenosis is presented. The method was tested against existing techniques using a model. By standardizing the distance from the objective of the endoscope to the stenotic area we were able to measure the cross-sectional area using a graduated grid held against the video screen. This technique was then compared with the standard one of estimating the diameter of a stenosis from the external diameter of the bronchoscope which can be passed through the stenosis. The methods were found to be equally accurate in measuring the lumen diameter. However, when measuring the minimum cross-sectional area, three of five observers were significantly better (P less than 0.01) using the photometric method rather than the standard method (Wilcoxon's rank sum test for paired data). The photometric technique of measuring the cross-sectional area of the subglottis is easily performed, non-traumatic, and allows a visual record to be kept.  相似文献   
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Positron emission tomography (PET) using [(11)C]PK 11195, a ligand for peripheral benzodiazepine receptor binding sites, offers the opportunity to image activated microglia in vivo. This tool may therefore be used to display the occurrence of microglial activation in the course of neurodegeneration. A patient with the clinical diagnosis of corticobasal degeneration (CBD) and left-sided symptoms was studied using fluorodeoxyglucose (FDG) and [(11)C]PK 11195 PET. We found a marked right hemispheric hypometabolism and asymmetric microglial activation in corresponding areas of the basal ganglia and right temporal and parietal cortex. [(11)C]PK 11195 PET suggests involvement of microglial activation in the pathogenesis of CBD.  相似文献   
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There are few records detailing the techniques and tribulations of early American surgeons who dared venture into the treacherous recess of the human orbit. The authors present a recently discovered letter written by a young woman who in 1841 underwent an orbital operation performed by the prominent New York City surgeon, Willard Parker. The letter details the patient's experiences in an era without anesthesia or antibiotics, and her subsequent development of conjunctival adhesions.  相似文献   
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Antihypertensive drugs are commonly associated with adverse side effects in both clinical and laboratory studies. We investigated the sexual sequelae of several major classes of antihypertensive drugs (e.g., beta blockers, central alpha agonists, diuretics) in normal males and in hypertensive patients. We compared the effects of four widely used agents (methyldopa, propranolol, atenolol, hydrochlorothiazide-triamterene) and placebo, in a selected sample of 21 sexually dysfunctional male hypertensives, 13 of whom completed all five phases of the study. Each study drug was administered for a 1-month treatment period, followed by a 2-week, single-blind washout phase, according to a randomized, Latin square crossover design. Dependent variables for the study included a broad range of hormonal, NPT, and self-report measures of sexual response. Results indicated a lack of consistent drug effects on measures of sexual response, although more frequent sexual and nonsexual side effects were observed with methyldopa and propranolol. As in our previous studies, age was negatively correlated with both hormonal and NPT measures, whereas changes in blood pressure were not significantly related to sexual function scores. Results do not support the hypothesis that sexually dysfunctional males are at greater risk for adverse sexual sequelae when treated with centrally active agents or diuretics.  相似文献   
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Simulation studies were conducted to address specific statistical issues which arise in the design and analysis of gingivitis studies whose principal aim is the demonstration of superiority or equivalence of one product to another. The effects of measurement scale, using differences or ratios of group means, particular statistical test produces and specific rules demonstrating superiority or equivalence were investigated. An alternative concept to equivalence—denoted “least as good”—was also defined and evaluated. For a wide class of possible distributions of gingivitis scores, characterized by specific gamma distributions, the student-t test applied to means of subject GI gingivitis scores proved to be the most powerful of the test produces considered, having statistical properties quite similar to the randomization or permutation test procedure. Transformations of subject GI mean gingivitis scores did not produce an advantage in demonstrating either superiority or equivalence, and in some cases made it more difficult. Little difference was observed in test results when using the difference in group means as compared with using the ratio of group means for demonstrating either equivalence or superiority. The clinically significant rule produced the lowest false-positive rates for products slightly better than the active control, and similar false-positive and -negative rates as the statistically significant rule for products clearly superior to the active control. Demonstration of product equivalence will require more subjects per group than demonstrating product superiority, the size of this difference being a function of the definition of superiority that is accepted. Showing that the 90% confidence interval for 100*R is completely contained within the [90%, 110%] interval is the preferred method of demonstrating equivalence today, although much more research needs to be done to improve methods for demonstrating product equivalence. The “least as good” alternative to “equivalence” makes it easier to demonstrate “equivalence” for products slightly better than the active control product, but both experience great difficulty in demonstrating equivalence for lest products not quite as good as the active control.  相似文献   
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The authors present a patient with a complex vascular malformation composed of bilateral spontaneous carotid-cavernous fistulas (CCF's). The abnormality was supplied on the right side by the right external carotid artery (ECA) and the right internal carotid artery (ICA), and on the left side only by the left ICA. There was also an arteriovenous communication between the right ECA and the lateral sinus. Surgical embolization of both cavernous sinuses with oxidized cellulose was achieved on one side by direct puncture and on the other through one of its venous affluents, successfully occluding both CCF's and preserving the patency of both ICA's without any neurological deficit. The arteriovenous communication between the right ECA and the lateral sinus was occluded by embolization of the occipital artery and ligation of the right ECA.  相似文献   
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