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21.
Examined the theory that chronic migraine headaches can lead to permanent changes in brain function in 71 female college students. Ss were 20 classic migraineurs, 27 common migraineurs, and 24 controls. No significant group differences were found on the Halstead Reitan Neuropsychological Test Battery and additional memory tests. Classic migraineurs had significantly higher scores than common migraineurs on the Hysteria and Paranoia scales of the Minnesota Multiphasic Personality Inventory (MMPI) and significantly higher scores than the controls on Hypochondriasis and Hysteria scales. Explanations for the lack of cognitive deficits in this group are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
22.
Aspiration biopsy of tumors and transplanted organs is a popular atraumatic method for diagnosis and also for the management of patients. Apart from the cytological analyses, it is clear that large aggregates of cells are obtained and these may be examined by electron microscopy. A study was carried out with dogs to assess the yield of intact glomeruli and tubules, resulting from a standard fine-needle aspiration procedure. Employing a 20-gauge needle, yields of approximately ten intact glomeruli were obtained with a tissue processing protocol that utilized filtration through a nylon mesh and backwashing, to resuspend the trapped aggregates. Processing for electron microscopy was carried out in microcentrifuge tubes. The ultrastructural preservation was excellent and the extension of these studies to investigations of not only renal transplantation, but also for diagnosis in human renal diseases of a broad spectrum, is suggested.  相似文献   
23.
Multimedia data from two probability-based exposure studies were investigated in terms of how missing data and measurement-error imprecision affected estimation of population parameters and associations. Missing data resulted mainly from individuals'refusing to participate in certain measurement activities, rather than from field or laboratory problems; it suggests that future studies should focus on methods for maximizing participation rates. Measurement error variances computed from duplicate-sample data were small relative to the inherent variation in the populations; consequently, adjustments in nonparametric percentile estimates to account for measurement imprecision were small. Methods of adjustment based on lognormality assumptions, however, appeared to perform poorly.  相似文献   
24.
Unicode is rapidly becoming the preferred means for representing symbols used in creating multimedia content, especially for information that's presented in multiple languages. This article discusses a unicode vulnerability that makes such content susceptible to being used for creation of covert channel communications. We also developed a solution architecture, the unified secure message augmentation (USMA) service. The USMA service incorporates rules (in an XML vocabulary) that we can apply to unicode transmissions that will detect an attempt to transmit a potential exploit, alert network managers to the presence of the unicode anomaly, and take action to mitigate the exploit.  相似文献   
25.
Surveyed the prevalence of weight reducing and weight gaining in 1,373 high school students. 63% of the girls and 16.2% of the boys reported being on weight-reducing regimens; 9.1% of the girls and 28.4% of the boys were trying to gain weight. Most female reducers and male gainers were already normal weight. Whites and Hispanics were more likely to be reducing, whereas Blacks were more likely to be gaining. Exercise and moderate caloric reduction were most popular for weight reducing, and a small but significant number were regularly using fasting, vomiting, laxatives, and appetite suppressants. The rate of weight reducing in female high school adolescents has increased significantly since similar surveys of American youths 20 yrs ago. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
26.
Finite element simulations of the high-temperature behavior of single-phase γ, dual-phase α2+γ, and fully lamellar (FL) α2+γTiAl intermetallic alloy microstructures have been performed. Nonlinear viscous primary creep deformation is modeled in each phase based on published creep data. Models were also developed that incorporate grain boundary and lath boundary sliding in addition to the dislocation creep flow within each phase. Overall strain rates are compared to gain an understanding of the relative influence each of these localized deformation mechanisms has on the creep strength of the microstructures considered. Facet stress enhancement factors were also determined for the transverse grain facets in each model to examine the relative susceptibility to creep damage. The results indicate that a mechanism for unrestricted sliding of γ lath boundaries theorized by Hazzledine and co-workers leads to unrealistically high strain rates. However, the results also suggest that the greater creep strength observed experimentally for the lamellar microstructure is primarily due to inhibited former grain boundary sliding (GBS) in this microstructure compared to relatively unimpeded GBS in the equiaxed microstructures. The serrated nature of the former grain boundaries generally observed for lamellar TiAl alloys is consistent with this finding.  相似文献   
27.
Factor V Leiden mutation was initially detected in thrombophilic patients and relatives by PCR RFLP (Restriction Fragment Length Polymorphism) according to Bertina (1). This technique presents some drawbacks and the current trend is to simplify the diagnosis. We describe a technique of Allele Specific Amplification (ASA) which is optimized in terms of reliability: an additional mismatch in antepenultimate position enables to obtain the same specificity as PCR RFLP. Furthermore, coamplification of internal control warrants an optimal sensitivity. All the PCR have been simplified: the DNA extraction improvement allows to analyse the genotype with only a few microliters of whole blood whatever the anticoagulant and the procedure of preservation (freezing, dried blood spots, storage at +4 degrees C for several days). This technique saves time. Moreover, full automation of the ASA technique may be shortened thanks to the lack of extraction and the positive/negative reading of the PCR signal.  相似文献   
28.
The road to employee empowerment runs between true commitment on the one side and enforced compliance and chaos on the other. By following this column's guidelines, IS managers can steer their organizations to success and help free employees to be more creative in terms of both quality and productivity.  相似文献   
29.
Helical distributions of stokeslets can valuably model microbial locomotion through a fluid, and also the flow field generated, wherever a flagellum actively executes helical undulations (as in many single-celled algae and protozoa) or where (as in many bacteria) the action of rotary motors causes a passive structure of helical shape (which may be a flagellum or else the cell body itself) to rotate. Here, previous biomechanical studies of such modes of locomotion are extended to include analyses of three-dimensional flow fields. In some cases, a rotlet field (curl of a stokeslet) needs to be incorporated in the models. For example, spirochete swimming is modelled by combined helical distributions of stokeslets and rotlets; the computed flow field being confined to within distances of less than twice the radius of the cell body's helical shape from its axis, while including a powerful jet-like interior flow through the coils of the swimming spirochete.  相似文献   
30.
Lorentz [1] pioneered the representation of flows at very low Reynolds number by a surface distribution of stokeslets — whose strengths, nowadays, are computed by surface-velocity collocations. That method is here compared with a representation widely used in flagellar hydrodynamics, by a curvilinear distribution of stokeslets and dipoles along the flagellar centreline; with the velocity of each cross-section expressed as a centreline value of the combined fields of singularities beyond a certain cutoff distance. The latter is also a good representation, and offers moreover some computational advantages. This paper establishes the equivalence of the two representations, and identifies those properties of Stokes flows which make both the dipoles and the cutoff essential to that equivalence.  相似文献   
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