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51.
Self-efficacy and AIDS Prevention for Pregnant Teens   总被引:1,自引:0,他引:1  
AIDS education, the only immediate solution to containment of AIDS, encourages active risk reduction among high-risk populations. Self-efficacy is a construct that can measure the likelihood preventive behaviors will be performed, and thus could be applied to identify specific areas where AIDS education should be augmented. In this study, pregnant, mostly black, teens (N = 58) attending an alternative school in a large, midwestern city completed a self-efficacy scale to identify self-perceived areas of vulnerability to participating in preventive behaviors and avoiding high-risk behaviors concerning AIDS. The AIDS Self-efficacy Scale identified four areas of greatest vulnerability: using condoms, discussing previous homosexual activity, discussing previous bisexual activity, and telling a partner about an experience with a bisexual. The last three situations result from an inability to discuss a partner's past sexual history, indicating a need to be very specific in these areas. School health interventions should recognize and deal with issues sexually active teens have identified as most difficult, particularly specific aspects of sexual histories, and provide these adolescents with prevention skills necessary to reduce high-risk behaviors.  相似文献   
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The bioenergetics of paralyzed muscles of spastic paraplegic patients under functional electrical stimulation (FES) was studied in vivo using 31P NMR. The protocol included rest, 3 min of induced tetanic isometric contraction through surface electrodes and 40 min of recovery. The continuous stimulation, the force recording and the 31P NMR measurements were sampled simultaneously inside the whole body imager. Normal values were found for the phosphorous metabolite ratios at rest. During contraction, prominent changes were detected including: a) accumulation of inorganic phosphate (P) accompanied by an unusually strong signal in the phosphomonoester (PME) region, b) phosphocreatine (PCr) decline, and c) a decrease in the intracellular pH. In the following recovery period the physiological state of the muscle was monitored and quantitated by 31P NMR. No metabolic and mechanical irreversible damage was detected in the paraplegics' muscles activated by FES under our experimental conditions.  相似文献   
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In light of evidence that certain aluminum-based antacids adhere to the gastric mucosa, we modified our previously described "artificial stomach" (AS) model by including a piece of hog stomach and compared the antacid activity of six aluminum-containing antacid products in the model with and without gastric mucosa. The activity of three of these, Maalox, Riopan and Supralox, was not significantly different in the two systems. In contrast, the activity of the other three, Aludrox, Phosphalugel and Simeco, was significantly greater with mucosa. Antacid activity of one product from each set (Supralox, Phosphalugel) was evaluated in two in vivo methods in human volunteers. For both antacids, results in vivo were similar to those obtained with the AS-containing mucosa. Without mucosa, in vivo and in vitro results were dissimilar for Phosphalugel, thus validating the modified AS. The difference between the two sets of antacids can be explained by 1) the fact that the Al:Mg ratio in the set affected by mucosa is greater than that of unaffected antacids, and 2) a weaker antacid load than in unaffected Supralox. We suggest that in an acid milieu, aluminum ions in antacids like Aludrox, Phosphalugel and Simeco are bound to sialic acid residues in mucus glycoproteins, thus retarding the transit of these antacids through both the AS and the real stomach and prolonging their activity in both situations. When the Al:Mg ratio is low or when the amount of antacid salts is large, aluminum ions tend to be buried in complexes, giving them less chance to interact with gastric mucus, so they transit the stomach more quickly.  相似文献   
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A knowledge-based Hypertext of Pathology integrating videodisc-based images and computer-generated graphics with the textual cognitive information of an undergraduate pathology curriculum has been developed. The system described in this paper was implemented under HyperCard00 during 1988 and 1989. Three earlier versions of the system that were developed on different platforms are contrasted with the present system. Strengths, weaknesses, and future extensions of the system are enumerated. The conceptual basis and organizational principles of the knowledge base are also briefly discussed.  相似文献   
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Evidence for autosomal recessive inheritance in cerebral gigantism   总被引:1,自引:3,他引:1       下载免费PDF全文
Three cases of cerebral gigantism, two sibs and their double first cousin, are described in a large inbred family from Israel. Two of the three were observed and diagnosed at birth and two were followed for two years. They all presented the signs and symptoms considered typical of this syndrome, as well as some of the less frequent findings. Generalized oedema and flexion contractures of the feet were observed in two of the three at birth. This has not hitherto been reported in cases of cerebral gigantism, of whom only a few have been observed and diagnosed at birth. Autosomal recessive inheritance is clearly implied in this family.  相似文献   
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The ability of the reticuloendothelial system (RES) to bind and catabolize soluble stable heat aggregates of 125I-IgG (A-IgG) was studied in mice given oral cadmium. Cadmium caused a delay in the circulation clearance of A-IgG in intact animals. The defect was due to impaired liver uptake of A-IgG and correlated with increased liver cadmium. Subsequent catabolism of bound A-IgG by liver slices was not affected. The defect was specific in that clearance of aggregated human serum albumin and colloidal carbon was normal in cadmium mice; this suggests that cadmium may affect either Fc or complement receptors of Kupffer cells in liver.  相似文献   
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