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21.
The rate of occurrence of antiphospholipid antibodies was compared in 47 patients with avascular necrosis of the femoral head and in 47 controls matched on age and sex. Antiphospholipid antibodies were looked for using three techniques in each patient, namely the VDRL test, an ELISA for anticardiolipin, and a circulating anticoagulant detection procedure involving three different tests. The VDRL and the tests for circulating anticoagulants were negative in all the patients and controls. No significant between-group difference was found for the ELISA, which was positive in three patients and two controls.  相似文献   
22.
This review provides an evaluation of the correlates and/or risk factors associated with disordered eating and the pursuit of muscularity among adolescent boys. One of the main conclusions is that similar factors and processes are associated with both behavioral problems. Several factors found to be consistently associated with disordered eating among boys are also similar to those found with girls. These include body mass index, negative affect, self-esteem, perfectionism, drug use, perceived pressure to lose weight from parents and peers, and participation in sports that focus on leanness. However, as many of the findings have only been verified using cross-sectional designs, prospective studies are now needed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
23.
This study examined factors that influence body image and strategies to either lose weight or increase muscle among children. Participants were 237 boys and 270 girls. Body mass index (BMI), body dissatisfaction, cognitions and behaviors to both lose weight and increase muscles, as well as self-esteem and positive and negative affect, were evaluated. Self-esteem was associated with body satisfaction, positive affect predicted strategies to lose weight and increase muscles, and negative affect predicted body dissatisfaction and cognitions to lose weight and increase muscles. Boys were more likely to focus on changing muscles. Respondents with higher BMIs were more focused on losing weight but not muscle. The discussion focuses on health risk behaviors related to eating and exercise among children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
24.
An encoded 13,020-member combinatorial library was synthesized containing a statine core. Evaluation of this library with plasmepsin II, an aspartyl protease required for hemoglobin metabolism in the malaria parasite, led to the identification of potent and selective inhibitors as well as novel structure-activity relationships.  相似文献   
25.
It is widely acknowledged that users of Spoken Language Systems (SLS) want the ability to truncate system prompts by using a barge-in capability (e.g., Basson et al., 1995; Yankelovich et al., 1995). However, little has been published on how barge-in is used or if it adversely affects Automatic Speech Recognition (ASR) and the interface usability. Typically, user requests for barge-in are assumed to be based on the desire to make system interactions faster and therefore more similar to interactions with touch-tone systems. We believe that requests for a barge-in capability are rooted in the notion of discourse as a turn-taking event. Viewed in this way, we believe SLS can be enhanced to develop speech interfaces that are deemed more natural by users, as well as to increase system performance. This study addressed several issues. We found that users new to the system did not need to be informed about the barge-in capability before they attempted barge-in, that they used barge-in during almost half of their interactions with the system, and that they had identifiable patterns of barge-in use consistent with the turn-taking model. Results are presented and consequences for speech interface design as well as algorithm enhancement are discussed.  相似文献   
26.
This paper deals with the problem of nonlinear reconstruction of a measurand or the so-called nonlinear inverse problem. Some criteria leading to the choice of the parametric models to be used in inverse problems are presented. It is demonstrated that some parametric functions are “better” than others when the final goal is an accurate estimate of some unknown quantity. Examples dealing with analytical functions or with a more realistic heat conduction problem are given  相似文献   
27.
Triacylglycerols (TAGs) from butter fat isolated by solvent extraction were analyzed by use of a capillary column supercritical fluid chromatograph (SFC) combined with a flame ionization detector or a double focusing mass spectrometer. The chromatographic separation was achieved by using a dimethyldiphenylpolysiloxane phase (DB-5) to bundle up the TAGs with the same carbon number. The ratio of TAGs with varying degree of unsaturation in each SFC peak was determined by using the selected ion monitoring of the molecular ions with electron impact mode. The discrimination between the fatty acids at the position sn-2 and positions sn-1/3 in a triacylglycerol molecule was demonstrated by monitoring the ions [M - RCO2CH2]+ from reference compounds.  相似文献   
28.
Describes a treatment program for males suffering from hypoactive sexual desire disorder. Treatment focused on developing the emotional aspects of the client, on increasing his sexual repertoire, and on improving his attitude and response to these sexual experiences in the context of each client's relationship. These aims were addressed by the use of communication exercises, sensate focus exercises, and guided fantasies. 15 men and their partners were so treated. While there was a decrease in the level of performance anxiety and sexual anxiety, Ss still experienced difficulty in level of sexual interest and in initiating sexual activity. At the 3- and 6-mo follow-up, the level of communication, sexual satisfaction, sexual arousal, and satisfaction with the relationship was still high. A case study is included. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
29.
A spreading code protocol (GBCR protocol)suitable for DS CDMA wireless data networks is proposedin this paper. The network is co-ordinated by a centralstation (CS) which maintains a database tracking each user's status. Users are divided intogroups, each of which is assigned a group-basedcommon (GBC) code used by a transmitter in thegroup to acquire the current state of its target. Data communication is allowed only after apositive ACK packet from the CS is received by thetransmitter, so that all successful terminals aresheltered by the CS from possible third-partyinterference which may use the same receiver-based code.Analytical results reveal that the GBCR protocol caneffectively improve network stability andthroughput-delay performance.  相似文献   
30.
Plant fibers are of increasing interest for use in composite materials. They are renewable resources and waste management is easier than with glass fibers. In the present study, longitudinal stiffness and strength as well as morphology of unidirectional sisal–epoxy composites manufactured by resin transfer molding (RTM) were studied. Horseshoe‐shaped sisal fiber bundles (technical fibers) were nonuniformly distributed in the matrix. In contrast to many wood composites, lumen was not filled by polymer matrix. Technical sisal fibers showed higher effective modulus when included in the composite material than in the technical fiber test (40 GPa as compared with 24 GPa). In contrast, the effective technical fiber strength in the composites was estimated to be around 400 MPa in comparison with a measured technical fiber tensile strength of 550 MPa. Reasons for these phenomena are discussed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2358–2365, 2002  相似文献   
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