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排序方式: 共有1974条查询结果,搜索用时 15 毫秒
1.
Five cases of coincident salmonellosis and ulcerative colitis are described. In three the diagnostic combination was recognized late. If corticosteroid therapy is given for the colitis once the combination is recognized, then simultaneous systemic antibiotic cover is advisable. One of the five patients died during corticosteroid therapy alone with salmonella septicaemia due to a usually non-invasive organism. 相似文献
2.
R Fletcher 《The British journal of physiological optics》1979,33(3):11-18
Closed circuit TV has proved to be a valuable aid for many patients with partial sight and a new device for magnification of printed material has been developed. This is in the form of a small camera, guided over the page by the subject's hand and incorporating a roller drive for a scanning mechanism. The scanning head fits into the hand easily; it is linked to an electronic TV receiver in the form of a mosaic. Tracking the scanner manually operates a flow of the display to the left, with new material emerging from the right of the screen. The present paper outlines an evaluation of the device under different conditions with patients. 相似文献
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4.
Asterios Triantafyllou David Fletcher John Scott 《Journal of molecular histology》2003,34(11-12):529-533
Catalytic activities of lingual lipase were investigated by enzyme histochemistry in post-mortem tongues from male rats. Sections of fresh-frozen or formalin-calcium fixed tissue were incubated with naphthol-AS-nonanoate and α-naphthyl acetate substrate mixtures. The effects of pH level, sodium taurocholate activator and E600 inhibitor were also examined. The use of cryostat sections of tissues fixed in formalin-calcium and of nonanoate substrate within the range of pH 4.4–6.4, were optimal for localizing maximum reaction product, captured by Fast Blue BB, in acini and demilunes of the posterior deep and superficial lingual glands respectively. The reaction product corresponded with the distribution of secretory granules and failed to develop when taurocholate was omitted from the incubation medium. Similarly localized E600-resistant reaction product occurred with the acetate substrate and hexazotized New Fuchsin at pH 7.4, in the absence of taurocholate. Lipase and conventional esterase activities appear to be superimposed in posterior lingual glands of rat. The ability of their acini and demilunes to hydrolyse nonanoate substrate at an acidic pH optimum, when activated by sodium taurocholate, seems attributable to lipase destined for secretion into saliva – hence convenient for routine histochemical identification of the enzyme. 相似文献
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6.
J. R. Daly M. R. Fletcher D. Glass D. J. Chambers Lucille Bitensky J. Chayen 《BMJ (Clinical research ed.)》1974,2(5918):521-524
The development of the highly sensitive cytochemical bioassay for ACTH has permitted the measurement of plasma ACTH levels during the insulin hypoglycaemia test (I.H.T.) in patients treated with corticosteroids and corticotrophin. The ACTH, corticosteroid, and growth hormone (GH) responses in the I.H.T. were measured in three groups of 12 rheumatoid arthritis patients. One group was receiving long-term corticotrophin treatment, the second was undergoing long-term corticosteroid treatment, and the third had never received systemic hormone therapy. The increments in plasma ACTH, corticosteroids, and GH were diminished in the corticosteroid-treated group, as were increments in plasma GH and ACTH in the corticotrophin-treated group; but in this group the corticosteroid increment was normal. Examination of the area under the curve of the ACTH response showed that the total amount of ACTH secreted was normal though the rate of secretion was reduced. In the corticosteroid-treated group both rate and total secretion were diminished. 相似文献
7.
S. Fletcher 《BMJ (Clinical research ed.)》1997,314(7083):764-765
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9.
M. D. Furones † D. J. Alderman D. Bucke T. C. Fletcher ‡§ D. Knox ‡ A. White ‡§ 《Journal of fish biology》1992,41(6):1037-1041
Rainbow trout fed diets containing 7, 86 or 806 mg vitamin E kg−1 for 22 weeks were exposed to virulent Yersinia ruckeri by bath or injection. Mortalities were always least among those fed the highest concentration of vitamin E but serum antibody production was not affected by vitamin E levels. 相似文献
10.
Resistance to the cytolytic action of lymphotoxin and tumor necrosis factor coincides with the presence of gap junctions uniting target cells 总被引:3,自引:0,他引:3
W H Fletcher W W Shiu T A Ishida D L Haviland C F Ware 《Journal of immunology (Baltimore, Md. : 1950)》1987,139(3):956-962
The resistance of target cells to the cytolytic action of lymphotoxin (LT) and recombinant tumor necrosis factor (rTNF) has been investigated by using clonally derived cell lines with defined gap junction-mediated, intercellular communication properties. Gap junction-competent Chinese hamster ovary cells are normally insensitive to the action of LT/TNF. However, treatment with 12-o-tetradecanoylphorbol-13-acetate, which promotes the loss of gap junctions, or culturing at low cell density to reduce intercellular contacts, significantly increased their sensitivity to LT/TNF. The LT/TNF-sensitive murine CL-1D and L929 cell lines, which in normal culture conditions are unable to form gap junctions, were not changed in their susceptibility to LT/TNF after treatment with phorbol ester or low culture density. However, the formation of gap junctions by CL-1D can be promoted by treatment with 8-bromo-cyclic adenosine monophosphate (1 mM), and this treatment completely suppressed the ability of LT and rTNF to kill CL-1D. Additionally, the LA25-normal rat kidney cell line, which is infected with a temperature-sensitive mutant of Rous sarcoma virus (LA25), is gap junction-competent and resistant to the effects of LT at the restrictive temperature (39 degrees C). However, when shifted to the permissive temperature (33 degrees C), LA25-normal rat kidney cells express the pp60v-src viral gene product, lose their ability to form gap junctions, and become sensitive to the lytic activity of LT. The results demonstrate that the expression of the retroviral pp60v-src, a tyrosine protein kinase, is sufficient to render cells susceptible to the lytic effects of LT and rTNF. Collectively, these experiments demonstrate a strong correlation between the resistance of target cells to the action of LT/TNF and their ability to cooperate metabolically through gap junctions. The results do not completely exclude the possibility that other mechanisms, such as LT receptor modulation, are also occurring under these experimental conditions. These data also suggest that a possible physiologic function of the stable cytotoxic lymphokines is to induce cytolysis/cytostasis of cells that have lost gap junctional contact, such as those in the process of mitosis or metastasis that have separated from the main tissue mass. 相似文献