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101.
A study of 10 infants in severe metabolic acidemia (pH below 7) led to the conclusion that the clinical signs—hyperventilation, coma or lethargy, peripheral vascular collapse, a significantly palpable liver, and abdominal distension—may all be directly related to the metabolic acidemia. In five of 10 infants, an initial erroneous diagnosis of congestive heart failure or pneumonia was made. Dramatic clinical improvement followed correction of the acidemia with rapid intravenous administration of sodium bicarbonate. This rapid administration of sodium bicarbonate was safe, provided hypocalcemia was recognized and treated in its early stages. In severe metabolic acidemia the measurement of blood bicarbonate alone does not reflect adequately the magnitude of the acid-base derangement and repeated measurements of hydrogen ion concentration, Pco2 and bicarbonates are needed to evaluate and treat such infants correctly. 相似文献
102.
William B. Critchfield 《American journal of botany》1960,47(8):699-711
Critchfield , William B. (Pacific SW Forest & Range Expt. Sta., Berkeley, Calif.) Leaf dimorphism in Populus trichocarpa. Amer. Jour. Bot. 47 (8) : 699–711. Illus. 1960.—In Populus trichocarpa and other species of Populus, each tree bears 2 kinds of leaves, referred to here as “early” and “late” leaves. Both leaf types are present on all long shoots. They differ in many features of external morphology, including petiole length, size and occurrence of marginal glands, venation, and stomatal distribution. This type of foliar dimorphism has its origins in a pronounced difference in leaf ontogeny. The early leaves originate in the developing bud and overwinter as embryonic leaves. The first late leaves are also present in the winter bud, but as arrested primordia, and succeeding late leaves are initiated at the tip of the growing shoot and develop uninterruptedly to maturity during the growing season. A similar correlation between leaf form and the circumstances of leaf ontogeny appears to be a common feature of many other instances of heterophylly. The expansion of the pre-formed early leaves is almost completed by late spring, when the first late leaves begin to grow rapidly. The formation of late leaves may then continue until late in the season. The rapid elongation of the stem does not begin until the first late leaves expand. Elongation is restricted to shoots producing late leaves. Consequently, the early leaves are confined to short shoots and the base of long shoots; adventitious shoots and the upper part of long shoots bear only late leaves. Certain other woody plants with long and short shoots also exhibit a restriction of elongation to those shoots on which a second set of leaves is produced. 相似文献
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105.
New localities in southern Illinois have yielded a flora consisting of 9 taxa. The plant remains occur in sandstones of the Chester Series and consist of casts, molds, and flattened impressions. The most important elements in the flora are: Archaeocalamites radiatus, Lepidodendron volkmannianum, Stigmaria ficoides, Rhynchogonium fayettevillense, and an unnamed Trigonocarpus. Stems probably referable to Lepidodendron veltheimii and Dictyoxylon also occur, as do numerous casts of the Knorria and Bergeria types. The range of features found in specimens of Lepidodendron volkmannianum allows some revision to be made of several species previously described by White in the Wedington Sandstone flora of northwest Arkansas, with which the present flora is closely comparable. The difficulties in making precise correlations with Upper Mississippian floras in other parts of the world are discussed. The necessity for critical re-examination of existing described collections and of undertaking more extensive field-work in the Mississippian of N. America is emphasized. 相似文献
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The records of 2,377 patients with Laennec''s cirrhosis were reviewed for the period 1947-1957. The chief presenting symptom was ascites in 46 per cent, bleeding in 23 per cent, coma in 18 per cent, jaundice in 9 per cent, and both jaundice and ascites in 4 per cent. Nearly half of the patients died during the period under study—one-third from hepatic failure, one-third from gastrointestinal bleeding, and one-third from other causes, most of which were related to alcoholism.Massive gastrointestinal bleeding occurred in 21 per cent of the patients at some time in their clinical course, and in the 10 per cent of these in whom ulcer was demonstrated, one-fifth died as a result of the hemorrhage. Of those presumed to be bleeding from esophageal varices, 64 per cent died at the first hemorrhage and 10 per cent at subsequent hemorrhages; 85 per cent of all those who bled from varices were dead at the end of one year, and 91 per cent were dead at the end of three years.The survival curve of a group of patients who bled once and were good operative risks but had received no operative treatment was compared to the survival curve for entire group who survived the first hemorrhage. The three-year survival in the good risk group was 47 per cent; for the group as a whole it was 30 per cent. The difference in mortality rate was primarily due to an increased number of deaths from hepatic failure in the combined group, whereas 60 per cent of the good risk group died of recurrent gastrointestinal hemorrhage.As 86 per cent of those who were to die of gastrointestinal bleeding did so at the first hemorrhage, it was concluded that any decided improvement in the salvage rate achievable by operation must come from some means of diagnostic forecast of the likelihood of bleeding, with resort to prophylactic operation in such cases. 相似文献
108.
William M. O'Leary 《Journal of bacteriology》1959,78(5):709-713
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