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11.
In three cases of cancer (arising in the pancreas, the breast and the lung) that had metastasized to the thyroid an unusual primary thyroid lesion was the presenting problem. While reputedly rare, metastases in the thyroid gland are not infrequently encountered at necropsy. These cases illustrate the varied causes of goitre, the value of needle aspiration and cytologic study in thyroid disease and the need for histologic vigilance. Worthwhile palliation by simple means can be obtained in such cases. 相似文献
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Lipid-protein globules of avian egg yolk. Isolation and properties of globules stable in concentrated sodium chloride solution. 总被引:1,自引:0,他引:1 下载免费PDF全文
A new type of globular particle, the 'insoluble yolk globule', was isolated from the egg yolk of three avian species (hen, duck, and emu) by centrifugation or gel-filtration chromatography. These globules are stable in NaCl and urea solutions at concentrations that dissolve or disrupt other constituents of yolk, The isolated globules are about 1% of the dry yolk of hen's and duck's eggs but about 8% emu's-egg yolk. Most of these globules are less than 2 micrometer in diameter. Electron micrographs of sections show a preponderance of globules in the range 0.125-0.25 micrometer, each with a thick shell surrounding a feature-less anterior. Globules with the same appearance were seen in sections of unfractionated yolk. Two kinds of larger particles were also observed: (i) particles with a distinct outer membrane and a vesiculated interior; (ii) featureless spheres, possibly of lipid. The insoluble yolk globules comprise protein (8-11% by dry wt.), phospholipid (31-35% total lipid), triacylglycerols (49-53%), cholesterol (8%) and cholesteryl esters (2-3%); the variations being among species. The phospholipid is accessible to phospholipase C. The isolated protein is heterogeneous and resembles the apoprotein from the yolk low-density lipoprotein. 相似文献
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The peripheral nerve allograft in the primate immunosuppressed with Cyclosporin A: II. Functional evaluation of reinnervated muscle. 总被引:1,自引:0,他引:1
Isometric contractile function was evaluated in primates receiving peripheral nerve allografts and autografts. Twelve adult male cynomolgus monkeys received both sural nerve allografts and autografts to the ulnar nerve in opposite forearms. Half the animals received Cyclosporin A (CsA) immunosuppression (25 mg/kg per day); the remaining animals received placebo. One year following nerve engraftment, isometric contractile muscle function was evaluated in reinnervated abductor digiti quinti and intact abductor pollicis brevis muscles. Maximal twitch tension (Pt), tetanic tension (P(o)), time to peak tension (tpt), rate of rise of twitch tension (DP/dt), and muscle fatigue were evaluated at optimal muscle length (L(o)). All reinnervated muscles distal to nerve autografts and allografts in both Cyclosporin A-immunosuppressed and placebo-treated animals generated equivalent maximal twitch tension, tetanic tension, and time to peak tension, with no significant difference between groups (p > 0.05 by ANOVA). There was a tendency toward increased muscle fatiguability in Cyclosporin A-treated animals (p > 0.05). However, the rate of rise of twitch tension was significantly faster in the reinnervated and intact muscles of Cyclosporin A-treated primates (p < 0.05). Evidence of excellent functional reinnervation across nerve allografts and autografts similar to that seen in histologic and electrophysiologic studies was noted. Cyclosporin A immunosuppression did not significantly enhance recovery of muscle function distal to nerve allografts in this model. 相似文献
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High-resolution linkage mapping for susceptibility genes in human polygenic disease: Insulin-dependent diabetes mellitus and chromosome 11q 总被引:12,自引:7,他引:5 下载免费PDF全文
R. N. Hyer C. Julier J. D. Buckley M. Trucco J. Rotter R. Spielman A. Barnett S. Bain C. Boitard I. Deschamps J. A. Todd J. I. Bell G. M. Lathrop 《American journal of human genetics》1991,48(2):243-257
Insulin-dependent diabetes mellitus (IDDM) has a complex pattern of genetic inheritance. In addition to genes mapping to the major histocompatibility complex (MHC), several lines of evidence point to the existence of other genetic susceptibility factors. Recent studies of the nonobese diabetic mouse (NOD) model of IDDM have suggested the presence, on mouse chromosome 9, of a susceptibility gene linked to the locus encoding the T-cell antigen, Thy-1. A region on human chromosome 11q is syntenic to this region on mouse chromosome 9. We have used a set of polymorphic DNA markers from chromosome 11q to investigate this region for linkage to a susceptibility gene in 81 multiplex diabetic pedigrees. The data were investigated by maximization of lod scores over genetic models and by multiple-locus affected-sib-pair analysis. We were able to exclude the presence of a susceptibility gene (location scores less than -2) throughout greater than 90% of the chromosome 11q homology region, under the assumption that the susceptibility factor would cause greater than 50% of affected sib pairs to share two alleles identical by descent. Theoretical estimates of the power to map susceptibility genes with a high-resolution map of linked markers in a candidate region were made, using HLA as a model locus. This result illustrates the feasibility that IDDM linkage studies using mapped sets of polymorphic DNA markers have, both for other areas of the genome in IDDM and for other polygenic diseases. The analytic approaches introduced here will be useful for affected-sib-pair studies of other complex phenotypes. 相似文献
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Blood counts were performed on 100 male and 100 female staff to establish normal ranges for our hospital. Neutrophil counts were found to be on average 0.66 times 10-9/1 (660/mm-3) higher in women than in men. Statistically this difference was highly significant and was not due to the fact that many of the women were taking oral contraceptives. The neutrophil counts of the men and women were also on average 0.50 times 10-9/1 (500/mm-3) greater in the afternoon than in the morning. A correlation was observed between the neutrpphil and the monocyte counts. 相似文献
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John Butterworth Grant R. Sutherland David M. Broadhead A.Douglas Bain 《Life sciences》1973,13(6):713-722
A number of factors which may correlate with the levels of α-glucosidase and β-glucosidase in cultured amniotic fluid cells have been investigated. Fluctuations in enzyme activity occurred as passage numbers increased. Whereas α-glucosidase showed a consistently lower activity in the earlier passages compared to the later ones, the results for β-glucosidase were equivocal. Both enzymes showed an increase in activity correlated with the time taken by the cells to reach confluency in the third passage. When replicate cultures were assayed daily after subculture, neither enzyme showed any change correlated with time. When cultures were grown in parallel in Ham's F10 and Eagle's M.E.M. tissue culture media, the activity of both enzymes was unaffected. Cell strains cultured from serial samples of amniotic fluid from the same woman had differing enzyme levels unrelated to gestational age. 相似文献