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91.
Fluorescence microscopy of caudal epididymal spermatozoa stained with 3, 3' dihexyloxacarbocyanine iodide (DiOC6(3)) showed intense fluorescence along the concave surface of the apical hook of spermatozoa of Rattus species and along the upper concave margin of the sperm head in Mus musculus. In the spermatozoa of Hydromys chrysogaster, Melomys cervinipes, and Pseudomys australis, the two ventral processes also fluoresced brightly. In P. australis, fluorescence in the apical hook of sperm heads was largely localized to its upper and lower surfaces. The sperm of N. alexis did not show consistent positive fluorescence. The localization of fluorescence in these spermatozoa after staining with DiOC6(3) was mainly restricted to regions where a large accumulation of perinuclear theca material lies beneath the plasmalemma. The reason for this remains to be determined, but DiOC6(3) may be useful for quickly demonstrating areas of abundant perinuclear thecal material in sperm heads of eutherian mammals by light microscopy.  相似文献   
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Rabbit aorta contracting substance-releasing factor (RCS-RF) is found in perfusates from guinea pig lungs during anaphylaxis. It has been identified as a small peptide which releases arachidonic acid from lung tissue, thus generating prostaglandin endoperoxides and tbromboxanes and causing bronchocconstriction. Anti-inflammatory steroids block the release of arachidonate by RCS-RF. In this activity their relative potency is very similar to their relative anti-inflammatory potency, suggesting that the two actions may be related.  相似文献   
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A patient with metastatic adenocarcinoma of the stomach developed microangiopathic haemolytic anaemia, thrombocytopenia, renal insufficiency, and fluctuating neurological abnormalities in association with appreciably raised plasma concentrations of immune complexes. This syndrome, similar to thrombotic thrombocytopenic purpura, occurred while the tumour was in sustained objective remission after successful treatment with fluorouracil, doxorubicin, and mitomycin. Reversal of the syndrome was achieved with plasmapheresis, azathioprine, corticosteroids, and antiplatelet treatment; this response was paralleled by a reduction in immune complex concentration, suggesting an immune aetiology for the syndrome. Antibodies eluted from the immune complexes reacted with 50% of cells from the gastric cancer but less than 10% of cells from normal gastric mucosa. There was no reactivity with either carcinoembryonic antigen or mitomycin. A 17S immune complex reacted with a glycoprotein from the patient's autologous platelets and produced platelet aggregation. It is postulated that reducing the tumour and the pre-existing state of antigen excess by chemotherapy allowed soluble antigen-antibody complexes to form and the syndrome to develop.  相似文献   
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Verbal suggestions combined with an elaborate placebo ritual and apparatus (polygraph, relay rack, and oscilloscope) eliminated headaches, nightmares, and nocturnal enuresis in a 10-yr-old girl. S had no prior history of abnormal or maladaptive behavior and had begun exhibiting the problem behaviors after a serious accident. Treatment consisted of 4 placebo sessions. Target behaviors decreased rapidly and in a sequence consistent with a psychophysiologic analysis of their components but somewhat inconsistent with apparent sources of reinforcement. Treatment effects are attributed to cognitive process variables such as expectancy and attribution. Treatment gains were maintained at a 24-mo follow-up. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The Buschke-Loewenstein tumor has a malignant clinical character but is histologically similar to the ordinary condyloma. The tumor grows deeply without invading the tissues, but compresses them and causes an intense inflammatory reaction. The diagnosis is clinical. Treatment with podophyllin and radiotherapy are not effective but bleomycin may be effective. Surgery is the accepted treatment and the extent of resection depends on the extent of the tumor.  相似文献   
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Serotonin (5-hydroxytryptamine, 5-HT) in blood is stored in platelets and has vascular and platelet stimulating effects when released into plasma. Accurate measurements of 5-HT in plasma are complicated by inadvertent platelet activation causing sampling artifacts and by analytical problems when determining trace levels. We developed an assay for plasma 5-HT based on solid-phase extraction (Sep-Pak C18), aqueous acetylation, pentafluoropropionylation, and negative ion chemical ionization gas chromatography-mass spectrometry. The method was able to recover 5-HT from plasma by > 90% and to quantitate with a precision of 7.5% at a level of 0.5 nmol/l. It was used to define blood sampling and sample handling procedures giving low and consistent values for 5-HT. A good blood sampling technique, adequate platelet stabilization in the test tube, and rapid high speed centrifugation of the blood resulted in low plasma levels of both 5-HT and beta-thromboglobulin (a platelet release product). Using these procedures plasma 5-HT levels in healthy volunteers were found to be 0.77 +/- 0.38 (mean +/- S.D.; range 0.27-1.49) nmol/l (n = 18), which is 4-100-fold lower than previously reported values.  相似文献   
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