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111.
Focal and segmental, but not generalized, myoclonus have been described with human immunodeficiency virus (HIV) infection. We describe three patients with generalized myoclonus and acquired immunodeficiency syndrome (AIDS) dementia complex. In each, myoclonus persisted until death, invariably after a course of a few months. In two patients, myoclonus was elicited by sudden auditory stimuli and resembled a startle response. This form of myoclonus may be subcortical in origin. We suggest that the AIDS dementia complex be included among the causes of myoclonic dementia. 相似文献
112.
Elena N Lopez Vani Nath Simmons Gwendolyn P Quinn Cathy D Meade Thomas N Chirikos Thomas H Brandon 《Nicotine & tobacco research》2008,10(1):87-96
The development of smoking cessation and relapse prevention interventions for pregnant and postpartum women is a public health priority. However, researchers have consistently reported substantial difficulty in recruiting this population into clinical trials. The problem is particularly acute for relapse prevention studies, which must recruit women who have already quit smoking because of their pregnancy. Although these individuals are an important target for tobacco control efforts, they represent an extremely small subgroup of the general population. This paper describes multiple recruitment strategies used for a clinical trial of a self-help relapse prevention program for pregnant women. The effectiveness of the strategies and the direct expense per participant recruited are provided. A proactive recruitment strategy (telephoning women whose phone numbers were purchased from a marketing firm) was ultimately much more successful than a variety of reactive strategies (advertisements, press releases, direct mail, Web placement, health care provider outreach). We found few differences between proactively and reactively recruited participants on baseline variables. The primary difference was that the former had smoked fewer cigarettes per day and reported lower nicotine dependence prior to quitting. Strengths and limitations of the recruitment strategies are discussed. 相似文献
113.
Designed 2 studies to investigate the forbidden fruit effect in 83 3rd and 4th graders. Results indicate (a) no support for a forbidden fruit effect, (b) that procedural aspects other than the prohibition in the forbidden toy paradigm influenced the child's valuation of the entire toy set, and (c) that there is a necessity for an appropriate comparison condition when using the forbidden toy paradigm. These results are extended to the previous research on the sour grapes effect. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The tensile yield stress is compared with the uniaxial compression yield stress for specimens of polycarbonate tested at constant
strain rate from −120 to + 120°C. The strain rate dependence of the tensile yield stress is also studied from − 140 to + 20°C.
The yield behaviour is described by a modification of the Eyring theory of non-Newtonian viscosity where the deformation is
supposed to involve two different flow processes.
The validity of a yield criterion previously established by one of us, is checked throughout the range of temperatures explored;
the proposed equation gives a good fit to the data provided it is applied separately to each flow process.
Then the present investigation, combining the yield condition with the modified Eyring theory, provides a formalism which
agrees with the data and accurately renders the temperature, strain rate and pressure dependence of the yield stress of polycarbonate. 相似文献
116.
The flow, heat and mass transfer on the unsteady laminar incompressible boundary layer in micropolar fluid at the stagnation point of a 2-dimensional and an axisymmetric body have been studied when the free stream velocity and the wall temperature vary arbitrarily with time. The partial defferential equations governing the flow have been solved numerically using a quasilinear finite-difference scheme. The skin friction, microrotation gradient and heat transfer parameters are found to be strongly dependent on the coupling parameter, mass transfer and time, whereas the effect of the microrotation parameter on the skin friction and heat transfer is rather weak, but microrotation gradient is strongly affected by it. The Prandtl number and the variation of the wall temperature with time affect the heat-transfer very significantly but the skin friction and micrortation gradient are unaffected by them. 相似文献
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Step voltage transient current studies have been made in cellulose acetate films as a function of filed and thickness. A logarithmic plot (Scherr-Montroll plot) of the transient current vs. time gives a knee at a time tT, which is interpreted as the transit time of the charge carrier. The value of the carrier mobility has been estimated to be 3.9 × 10?9 cm2.V?1.S?1 in cellulose acetate film. The carrier mobility in iodine-doped (2% w/w) cellulose acetate film has also been determined from Scher-Montroll plot and is found to be 3.3 × 10?7 cm2.V?1.S?1. 相似文献