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Argues that the selection of response categories for summated rating (Likert) scales is often made arbitrarily; however, the equal interval properties of the response continuum is assumed even though this assumption may in fact, be false. To avoid the problems that unequal intervals might cause, it is suggested that equal interval categories be used. To this end, 3 lists of commonly used categories (agreement, evaluation, and frequency) were scaled, using data from 107 undergraduates. The scale values are presented to aid the researcher in choosing response categories; however, it is suggested that separate scale values be derived for each population sampled. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
955.
We recently encountered a patient with severe flatulence who previously had been subjected to innumerable diagnostic tests and ineffective therapies based on the belief that his rectal gas was produced in the colon. Analysis of three flatus samples demonstrated that nitrogen (N2) was the predominant flatus gas whereas the three gases produced in the gut (CO2, H2 [hydrogen], and CH4 [methane]) comprised <16% of rectal gas. This result plus a series of other diagnostic tests clearly indicated that the patient's flatus was derived almost entirely from swallowed air. Based on this case, the present report summarizes available data on excessive flatulence and suggests a rational approach to the patient complaining of this problem. Particular emphasis is placed upon a sequential strategy consisting of: 1) a count of flatus passages to determine if the subject truly is abnormal (normal: <20 passages/day); 2) an analysis of flatus to determine if the flatus originates from swallowed air (predominantly nitrogen) or intraluminal production (predominantly CO2, H2, and CH4); and 3) treatment based upon the origin of the rectal gas. 相似文献
956.
Scopulariopsis acremonium is a species of saprophytic fungus not previously reported to cause invasive disease in humans, although invasive infections from other species of Scopulariopsis have been reported and are reviewed. Deep infection with this fungus is associated with a high mortality rate. Invasive fungal sinusitis, in general, is a potentially fatal disease that typically affects immunocompromised patients, such as those receiving intensive chemotherapy or undergoing bone marrow transplantation. We report a case of invasive fungal sinusitis caused by Scopulariopsis acremonium in a patient with leukemia, who was successfully treated with amphotericin B, itraconazole, endoscopic sinus surgery, and granulocyte colony-stimulating factor. 相似文献
957.
S Parry J Holder MW Halterman MD Weitzman AR Davis H Federoff JF Strauss 《Canadian Metallurgical Quarterly》1998,152(6):1521-1529
We investigated the transfer of the lacZ reporter gene into human trophoblastic cells using herpes simplex virus and adeno-associated virus vectors. We used an established choriocarcinoma cell line (BeWo cells) that can be induced to terminally differentiate after treatment with cyclic-AMP. Our results demonstrate that transduction of trophoblastic cells by the herpes simplex virus vector, HSV.CMVlac, and the adeno-associated virus vector, AAV.CMVlac, is affected by cellular differentiation. Treatment of BeWo cells with cyclic-AMP reduced transduction by HSV.CMVlac but increased transduction by the AAV vector. In contrast, when BeWo cells were transfected with herpes simplex virus and adeno-associated virus plasmids, lacZ expression was not affected by treatment with cyclic-AMP. Southern blot analysis demonstrated 2.75 times less herpes simplex virus DNA in cyclic-AMP treated BeWo cells, but 2.0 to 7.4 times more adeno-associated virus DNA in treated cells. We conclude that inefficient transduction of differentiated trophoblastic cells with HSV.CMVlac is because of diminished viral entry, whereas cellular differentiation is associated with increased entry of AAV.CMVlac. These observations suggest that adeno-associated virus vectors may be used to modify trophoblast function and study placental physiology. Additionally, trophoblast differentiation leads to alterations in the mechanisms of virus uptake that may affect maternal-to-fetus transmission. 相似文献
958.
CP Cannon CH McCabe S Borzak TD Henry MD Tischler HS Mueller R Feldman ST Palmeri K Ault SA Hamilton JM Rothman WF Novotny E Braunwald 《Canadian Metallurgical Quarterly》1998,97(4):340-349
In fMRI studies, Gaussian filtering is usually applied to improve the detection of activated areas. Such lowpass filtering enhances the signal to noise ratio. However, undesirable secondary effects are a bias on the signal shape and a blurring in the spatial domain. Neighboring activated areas may be merged and the high resolution of the fMRI data compromised. In the temporal domain, activation and deactivation slopes are also blurred. We propose an alternative to Gaussian filtering by restoring the signal using a spatiotemporal Markov Random Field which preserves the shape of the transitions. We define some interaction between neighboring voxels which allows us to reduce the noise while preserving the signal characteristics. An energy function is defined as the sum of the interaction potentials and is minimized using a simulated annealing algorithm. The shape of the hemodynamic response is preserved leading to a better characterization of its properties. We demonstrate the use of this approach by applying it to simulated data and to data obtained from a typical fMRI study. 相似文献
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It is shown that theory of the Penning discharge essentially involves taking into account the collective interaction of the electrons in the near-anode region. Following investigations of the Penning discharge in a strong magnetic field (density up to 12 kOe) empirical formulae are proposed for calculating the pumping speed and the minimum operating pressures of getter-ion pumps. Methods of calculation for built-in getter-ion pump parameters and design peculiarities are considered. 相似文献