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J W Larrick C E Buckley C E Machamer G D Schlagel J A Yost J Blessing-Moore D Levy 《The Journal of allergy and clinical immunology》1983,71(2):184-188
The Waorani Indians of eastern Ecuador have the highest blood concentration of IgE reported in a human population. Evidence obtained by medical history, physical examination, and immediate hypersensitivity skin tests suggests that pollen allergy and other atopic diseases are rare among the Waorani. A similar association between parasite-induced hyperimmunoglobulinemia-E and a low prevalence of conventional atopic disease has been reported in numerous other tropical populations. Saturation of mast cell IgE receptors with antibodies directed to the parasite and/or other antigens and competitive inhibition of passive binding of pollen allergen-specific IgE is one hypothetical cause of this association. We have tested this interesting conjecture by passively sensitizing the skin of Waorani Indians with serum containing pollen allergen-specific IgE antibodies. Waorani Indians with hyperimmunoglobulinemia-E can be adoptively sensitized with human ragweed or rye grass hyperimmune IgE antisera. This suggests that the cutaneous mast cells of healthy Waorani have active IgE receptors. The high circulating plasma concentrations of IgE in the Waorani do not prevent adoptive cutaneous sensitization with pollen-specific IgE antibodies. 相似文献
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W G Hall 《Appetite》1985,6(4):333-356
Because suckling behavior differs in many ways from later ingestive behavior, the development of feeding and drinking in rats is best studied apart from the normal suckling situation. Newborn rat pups, separated from their mothers, will actively ingest diet infused into their mouths or spread on the floor beneath them. Such "independent" ingestion resembles the ingestive behavior of adult animals, but it also undergoes developmental changes in organization and control during the pre- and post-weaning periods: When young, deprived pups are fed, they show generalized, non-directed behavioral excitement; but with increasing age, this generalized responding matures into directed and focused ingestive activity. Early independent ingestion depends on a warm test environment; but with development, other familiar environmental and social cues come to influence responding. The internal controls of ingestion also change. Only gastric distension and hydrational status seem to be involved in controlling intake volume during early ingestion, with other ingestive controls emerging later in development. Thus ingestion, independent of suckling from the mother, is a system undergoing revealing developmental changes. These changes offer opportunities for studying ingestion, its controls, and its neural basis at its simplest organizational stage in the newborn, and at higher levels of complexity as maturation adds new components to the feeding system. 相似文献
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Kristen E. Rhodin Vignesh Raman Oliver K. Jawitz Soraya L. Voigt Norma E. Farrow David H. Harpole Betty C. Tong Thomas A. D’Amico 《The Annals of thoracic surgery》2021,111(2):440-447
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Raymond E. Ideker Galen S. Wagner Wayne K. Ruth Daniel R. Alonso Sanford P. Bishop Colin M. Bloor John T. Fallon Geoffrey J. Gottlieb Donald B. Hackel Harry R. Phillips Keith A. Reimer Steven F. Roark William J. Rogers Robert M. Savage Richard D. White Ronald H. Selvester 《The American journal of cardiology》1982,49(7):1604-1614
The ability of an independently developed QRS point score to estimate the size of infarcts predominantly within the anterior third of the left ventricle was evaluated by quantitative pathologic-electrocardiographic correlation. The study was limited to 21 patients with a single infarct documented by postmortem examination, for whom an appropriately timed standard 12 lead electrocardiogram was available that did not exhibit signs of left or right ventricular hypertrophy, left or right bundle branch block or anterior or posterior fascicular block. At necropsy the heart was cut into five to seven slices. The location and size of the infarct was quantitated by computer-assisted planimetry of the slices.The electrocardiogram of 19 (90 percent) of the patients exhibited either a Q wave or an R wave of no more than 20 ms in lead V2. The infarct in the two patients without this electrocardiographic finding was small, occupying 2 and 3 percent of the left ventricle, respectively. The percent infarction of the left ventricle correlated with the QRS point score (r = 0.80). Thus in patients without complicating factors in the electrocardiogram and with a single infarct, the electrocardiogram provides a marker for infarction in the anterior third of the left ventricle and permits estimation of infarct size. 相似文献
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R M Schneider K B Roberts K G Morris J A Stanfield F R Cobb 《The American journal of cardiology》1984,53(2):294-301
Multigated equilibrium radionuclide angiography was used to quantitate global and regional ejection fraction (EF) in 26 awake dogs 10 minutes after distal and then proximal occlusion of the left anterior descending (LAD) or left circumflex (LC) coronary artery. Changes in global and regional EF were correlated with simultaneous measurements of the extent of acute left ventricular (LV) ischemia measured by radioisotope-labeled microspheres. The extent of ischemia, defined as the percentage of LV mass with greater than 25% reduction in blood flow from normal regional flow, was linearly related to the percent change in global EF after LAD (r = 0.84) and LC (r = 0.77) occlusions. The extent of ischemia also correlated with regional EF (r = 0.47 to 0.88 for LAD and r = 0.41 to 0.69 for LC occlusions). In 24 of 25 LAD occlusions and in all 20 LC occlusions that produced a measurable ischemic zone, the maximal percent change in regional EF exceeded the percent change in global EF. Two LAD occlusions and 2 LC occlusions reduced regional EF but not global EF. Thus, global and regional EF decreased in direct proportion to the extent of acute myocardial ischemia; regional ischemia produced greater changes in regional than in global EF. 相似文献