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101.
An absolute lymphocyte count is included in the routine results provided by most automated blood cell counters, providing a prompt indication of peripheral blood lymphocytosis. Transient lymphocytosis is seen in many acutely ill patients, including those with multiple injuries. We have observed a significantly higher death rate among trauma patients with lymphocytosis at presentation; patients with lymphocytosis, on subsequent assessment of injury, proved to have higher Injury Severity Scores than those without lymphocytosis. Investigation of lymphocyte subsets in nine patients with lymphocytosis showed an increase in T cells, reversal of the CD4:CD8 ratio, and, in seven patients, an increase in "natural killer" cells. The presence of lymphocytosis and its early detection as part of a routine blood count may supply a readily available means of identifying a high-risk trauma patient.  相似文献   
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It has been speculated that exposure to the chronic stress of racism contributes to the high rates of hypertension among African Americans. Social support may buffer the effects of stress on cardiovascular (CV) health by attenuating stress-induced CV responses that have been linked to hypertension. In this study we investigated the effects of racism and social support on CV reactivity in African American women. Participants showed greater increases in CV and emotional responses while responding and listening to racist provocation. Augmented blood pressure (BP) persisted through recovery following racial stress. Participants receiving no support showed the greatest increases in anger during racist provocation. No significant effects were seen for support on CV reactivity. These results provide some of the first evidence that interactive confrontation with racism elicits significant increases in CV reactivity and emotional distress. Furthermore, individuals receiving less support may be at greater risk for the potentially health-damaging effects of racial stress. These findings may have significant implications for the health of African Americans.  相似文献   
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The dopamine hypothesis of schizophrenia proposed that dopaminergic pathways are involved in the etiology of the disease. In particular, interest among psychiatrists has focused on the D2 receptor because of its affinity to antipsychotic drugs. Recently a new dopamine receptor gene has been cloned, and named the dopamine D3 receptor. The D3 receptor is a potential site for antipsychotic drug action and may be involved in the pathophysiology of schizophrenia. We have carried out a linkage study between the susceptibility gene for schizophrenia and polymorphism of the dopamine D3 receptor gene in two Japanese pedigrees. The LOD scores were negative for, all genetic models and for all affective status at a recombination fraction θ = 0. Linkage of DRD3 has been excluded for the model 1 (dominant model) and the model13 (recessive model). The LOD score was - 3.43 at θ = 0 for model 1 (dominant model) and broad definition of affected status. These results were consistent with previous studies. © 1994 Wiley-Liss, Inc.  相似文献   
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Measurable amounts of viable and functional polymorphonuclear neutrophils (PMNs) are recovered from pooled washings of the gingival crevice of healthy individuals. In the present study, we have assessed the ability of the PMNs removed from single healthy or diseased pocket sites to mount an oxidative burst when challenged with phorbol myristate acetate (PMA) and compared these activities with each other and with those obtained with autologous peripheral-blood PMNs. The oxidative burst after PMA stimulation was evaluated by using methods developed for the flow cytometer. The results showed that the PMNs collected from untreated disease sites were minimally responsive to PMA when compared with peripheral-blood PMNs collected at the same time from the same individual. Thus, whereas the peripheral-blood PMNs exhibited significantly lower resting oxidative product formation and a 500% increase when stimulated with PMA, all gingival-crevicular PMNs exhibited significantly higher resting formation of oxidized products but only a 150% increase after PMA stimulation. PMNs obtained from a consistently healthy site had significantly higher resting production of oxidized products and were able to mount the greatest absolute increase in oxidized products after PMA stimulation when compared with PMNs collected from diseases sites. Mechanical debridement of these diseased sites, which both reduced the bacterial numbers and restored clinical health, resulted in the recovery of gingival-crevicular PMNs that exhibited an oxidative burst more typical of that observed in PMNs obtained from healthy gingival sites and from the peripheral blood. This suggested that the PMNs collected from the diseased sites either had been exhausted by the large numbers of bacteria present in these sites or had been specifically inhibited by these bacteria.  相似文献   
109.
AIMS/BACKGROUND: A major medical role for postmortem examinations is the detection of clinically unexpected disease processes contributing to death. The aim of the present study was to determine whether simple clinical parameters can predict the presence of important unanticipated findings at necropsy. METHODS: Prospective audit of adult necropsies carried out in a single year to assess the extent of unexpected findings at necropsy, to compare these cases with non-necropsied deaths to confirm they are a similar population and to seek features that predict which cases have unexpected necropsy findings. RESULTS: No correlation was found between age, sex, duration of in-hospital treatment, surgical intervention, clinical specialty, or necropsy request rates and incidence of unexpected findings in 187 adult necropsies. CONCLUSIONS: No parameters have been identified for patient selection to permit an increase in the yield of clinically unexpected findings. Until there is clear evidence that the current practice of patient selection is anything more than random, an increase in postmortem examination rates, as proposed by the Joint Working Party of the Royal College of Pathologists, the Royal College of Physicians of London and the Royal College of Surgeons of England in their report The Autospy and Audit, will increase the workload without necessarily producing a commensurate gain in knowledge.  相似文献   
110.
Thinning and dilatation (expansion) of the infarct region and complete rupture of the ventricular wall are significant complications of acute transmural myocardial infarction associated with increased morbidity and mortality. The pathogenesis of these related events is unknown. Recent studies of myocardial connective tissue have delineated an extensive array of intercellular and pericellular structures which serve as a skeletal framework and which may modulate contractile activity. We have employed a modified silver impregnation method to visualize the connective tissue components by light microscopy. To explore whether the skeletal framework is altered in acute myocardial infarction with and without ventricular rupture, we studied 9 human hearts at autopsy, and 4 canine infarcts of known duration. The human infarctions included 4 nonruptured cases with infarcts 1-5 days old, and 5 ruptured cases with infarcts 3-10 days old. Sections from normal, lateral, and central infarct or ventricular rupture sites were stained with silver. The normal tissue from each heart served as a control. Silver staining was moderately decreased in the lateral infarct zones, and markedly decreased in the central non-ruptured infarct zones. In the 5 ventricular rupture cases, the rupture site had no silver staining. A similar pattern was observed in the 4 canine infarcts. Thus, we conclude that the skeletal framework is markedly altered in the central zone of acute myocardial infarction. The acute changes of silver stained connective tissue may contribute significantly to the development of infarct expansion or ventricular wall rupture.  相似文献   
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