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Acute appendicitis still is a cause of considerable morbidity and now and then of death. The diagnostic accuracy in 316 patients operated on for acute appendicitis at Holy Cross Hospital was 76 per cent. In 24 of 239 cases of proved acute appendicitis, perforation had occurred, and the morbidity in those cases was three times that in the cases without perforation. Review of the cases did not reveal any clear-cut diagnostic criteria that might be used to predict perforation.A study of 30 patients with mesenteric lymphadenitis who were inadvertently operated on in the belief they had appendicitis, revealed that this condition is most likely to occur in young females with only a slight increase in the number of leukocytes. Although positive diagnosis of acute appendicitis is a difficult problem, the morbidity associated with needless operation is so much less than that which occurs in acute perforated appendicitis, that prompt exploration in any questionable case seems warranted.  相似文献   
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A reagent composed of 0.2% p-phenylenediamine in 2 N NH4OH was used for the cytochemical demonstration of arbutin in plant tissue. Sections of fresh tissue were cut at 25-50 μ, mounted in a drop of the reagent, and allowed to stand uncovered 15-20 min before applying a coverslip. Arbutin stained dark blue to dark purple and was easily distinguished from other constituents of the cell, such as chlorogenic acid, isochlorogenic acid, caffeic acid, and quinic acid, which stained yellow, yellow-green, red or brown in color. The limit of sensitivity of the p-phenylenediamine-arbutin reaction was 1:100,000, as determined by spot-plate tests.  相似文献   
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This research determined the relationships between blood lead level and zinc protoporphyrin (ZnPROTO), protoporphyrin IX (PROTO), and free erythrocyte protoporphyrin (FEP) levels in a group of 18 ring teal ducks. Blood samples were drawn from two groups of ring teal ducks as part of the routine health maintenance program of the New York Zoological Park. One group of six teals had been exposed to what is believed to be lead-contaminated dust, while the second group of twelve teals was unexposed. Blood samples were analyzed for lead by flameless atomic absorption and for protoporphyrins by fluorescence. Blood lead level and log blood lead level had positive correlations with each of the protoporphyrins: the logarithmic correlations were better than the nonlogarithmic correlations, and PROTO correlated better than ZnPROTO. With one exception, PROTO levels were higher than ZnPROTO levels. The results suggest that PROTO, FEP, or ZnPROTO could serve as a biological indicator of lead poisoning in ring teal ducks.  相似文献   
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Mild hypoferremia represents an aspect of the ability of the body to withhold iron from pathogenic bacteria, fungi, and protozoa, and from neoplastic cells. However, our iron-withholding defense system can be thwarted by practices that enhance iron overload such as indiscriminate iron fortification of foods, medically prescribed iron supplements, alcohol ingestion, and cigarette smoking. Elevated standards for normal levels of iron can be misleading and even dangerous for individuals faced with medical insults such as chronic infection, neoplasia, cardiomyopathy, and arthritis. We are becoming increasingly aware that the wide-spread hypoferremia in human populations is a physiological response to insult rather than a pathological cause of insult, and that attempts to correct the condition by simply raising iron levels may not only be misguided but may actually impair host defense.  相似文献   
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Summary It has been proposed that basic fibroblast growth factor (basic FGF) mediates the neovascular response in a variety of conditions, including diabetic retinopathy and branch retinal vein occlusion. To test the hypothesis that basic FGF was released from retinal stores as a result of retinal ischaemia, transient retinal ischaemia was induced, followed by 48 h of reperfusion, in the rat by combined central retinal vasculature and optic nerve ligation. The immunolocalization of basic FGF was studied in the retina. We found that basic FGF in the normal retina is present around the deeper retinal vessels and in the neuronal tissue of the outer plexiform layer. In the eyes that had ischaemia followed by reperfusion, there was moderate cellular oedema with retinal swelling, and mitoses in the inner nuclear and plexiform layers. There were no changes evident at the immunohistochemical level either in the intensity or distribution of stores of basic FGF. We conclude from these data that stores of basic FGF are not altered dramatically under the conditions of transient experimental ischaemia and reperfusion in the rat, despite the presence of cellular proliferation.  相似文献   
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