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31.
Factors relating to the transfer of latex microspheres of 0·87 μm mean diameter from the gastrointestinal tract (GIT) to the circulation have been investigated. The rapidity of appearance and the number of particles increased when the volume of water used as a suspending vehicle was increased. This was probably due to barrier cell integrity being compromised so that the movement of particles across the enterocytes would be enhanced. Particles were swept into these channels by the waterflow. The tonicity of the fluid was important as isotonic and hypertonic saline were not as affective as water in transferring particles. Particles were transferred from GIT segments adjacent to the stomach which may in part explain the rapid appearance of particles in the circulation. Particle uptake was blocked by cytochalasin B which suggests an active component may also be involved.  相似文献   
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Studied children with mild to moderate juvenile rheumatoid arthritiswho were massaged by their parents 15 minutes a day for 30 days(and a control group engaged in relaxation therapy). The children'sanxiety and stress hormone (cortisol) levels were immediatelydecreased by the massage, and over the 30-day period their paindecreased on self-reports, parent reports, and their physician'sassessment of pain (both the incidence and severity) and pain-limitingactivities  相似文献   
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BACKGROUND: Inhalation of sulphur dioxide (SO2) provokes bronchoconstriction in asthmatic subjects. Cholinergic mechanisms contribute, but other mechanisms remain undefined. The effect of morphine, an opioid agonist, on the cholinergic component of SO2-induced bronchoconstriction was investigated, and the effect of indomethacin, a cyclooxygenase inhibitor, on SO2-induced bronchoconstriction and tachyphylaxis was studied. METHODS: In the first study 16 asthmatic subjects inhaled either ipratropium bromide or placebo 60 minutes before an SO2 challenge on days 1 and 2. On day 3 an SO2 challenge was performed immediately after intravenous morphine. In the second study 15 asthmatic subjects took either placebo or indomethacin for three days before each study day when two SO2 challenges were performed 30 minutes apart. The response was measured as the cumulative dose causing a 35% fall in specific airways conductance (sGaw; PDsGaw35). RESULTS: Ipratropium bromide significantly inhibited SO2 responsiveness, reducing PDsGaw35 by 0.89 (95% CI 0.46 to 1.31) doubling doses. This effect persisted after correction for bronchodilatation induced by ipratropium bromide. The effect of ipratropium bromide and morphine on SO2 responsiveness also correlated (r2 = 0.71). In the second study SO2 tachyphylaxis developed with PDsGaw35 on repeated testing, being reduced by 0.62 (95% CI 0.17 to 1.07) doubling doses. Indomethacin attenuated baseline SO2 responsiveness, increasing PDsGaw35 by 0.5 (95% CI 0.06 to 0.93) doubling doses. CONCLUSIONS: These results suggest that opioids modulate the cholinergic component of SO2 responsiveness and that cyclooxygenase products contribute to the immediate response to SO2.  相似文献   
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A main objective of this study was to compare the emotional well-being of mothers who had already experienced a reunion with children relinquished two to four decades ago, with that of mothers who were still awaiting the possibility of such re-contact. A nationwide postal survey was carried out in New Zealand of the relinquishment experiences and subsequent adjustment of 238 women who had been able to re-contact their children and of 206 women who had not as yet made contact. The two subgroups did not differ on two standardised measures of psychological well-being (GHQ-28 and global self esteem). However, the post-reunion women reported significantly greater improvements in their feelings connected with "adoption events", and also reported higher levels of perceived social support than did the pre-reunion women. Women who still lacked any information about their relinquished child showed significantly more negative affect and poorer psychological well-being than those who had at least obtained some non-identifying information.  相似文献   
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Explants of neonatal rat cerebellum have been cultured on rat-tail collagen coated cover-slips for 2–4 weeks under conditions which yielded well myelinated nerve fibres suitable for testing myelotoxicity of serum. Eighty-four per cent of twenty-five acute multiple sclerosis serum samples were myelotoxic, as opposed to 62% of twenty-six sera from cases of motor neurone disease. Twenty-four per cent of thirty-four normal sera also showed distinct myelotoxicity. The difficulties in setting up and interpreting tests for in vitro demyelinating activity of serum are discussed. Six spinal fluids from acute cases of multiple sclerosis were without activity. It is concluded that although myelotoxicity exists in most samples of serum from acute multiple sclerosis, it is not limited to such subjects and that its high incidence in motor neurone disease sera indicates that it may well be a consequence of myelin destruction rather than a primary factor in its causation.  相似文献   
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Thirty-nine bereaved individuals completed the Continuing Bonds Scale (CBS), assessing various aspects of the ongoing attachment to the deceased, at 60 months postloss in a longitudinal conjugal bereavement study. They also completed symptom measures at 6, 14, 25, and 60 months postloss. Higher CBS scores were associated with a more elevated grief-specific symptom pattern over the 5-year postloss period. Moreover, those who expressed greater helplessness and less blame toward the deceased during a monologue role-play involving their deceased spouse at 6 months postloss had higher CBS scores. Finally, greater satisfaction in the past relationship with the spouse was predictive of higher CBS scores. The results were discussed in relation to existing literature on the adaptiveness of continuing bonds.  相似文献   
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Experimental autoimmune gastritis (EAG) is an excellent model of human autoimmune gastritis, the underlying cause of pernicious anaemia. Murine autoimmune gastritis replicates human gastritis in being characterized by a chronic inflammatory mononuclear cell infiltrate in the gastric mucosa, destruction of parietal and zymogenic cells, and autoantibodies to the alpha-and beta-subunits of the gastric H+/K+ ATPase. Disease is induced strain specifically in gastritis-susceptible BALB/c mice by methods with a greater variety than those for most other experimental autoimmune diseases. The disease is induced in the regional gastric lymph node in which pathogenic CD4+ T cells are recruited. The model provides an excellent illustration of regulation by CD4+CD25+T cells, and, indeed, the removal of such regulatory cells, e.g., by neonatal thymectomy, is thought to be a major mechanism by which disease can develop. The culprit T helper type 1 (Th1) CD4+ T cells recognize either the alpha- or beta-subunits of the gastric H+/K+ ATPase, but the beta-subunit appears to be the initiating autoantigen, while the alpha-subunit may have a role in perpetuating disease. Since no specific environmental modifiers are identifiable, the origins of the disease are intrinsic; this is illustrated by the capacity of a cytokine (GM-CSF)-dependent inflammatory stimulus in the stomach to initiate EAG, according to a transgenic model in which thymectomy is dispensible. Thus, EAG is an exquisite model for a reductionist analysis of the multiple elements that in combination induce autoimmunity in humans.  相似文献   
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