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排序方式: 共有751条查询结果,搜索用时 15 毫秒
91.
92.
Edward E. Nishizawa William L. Miller Robert R. Gorman Gordon L. Bundy Jan Svensson Mats Hamberg 《Prostaglandins & other lipid mediators》1975,9(1)
Prostaglandin D2 was found to be a potent inhibitor of platelet aggregation. Aggregation of human platelets by ADP, collagen and prostaglandin G2 was inhibited more strongly by PGD2 than by PGE1. Although ADP-induced aggregation of rabbit platelets was inhibited more strongly by PGE1 than by PGD2 the latter prostaglandin gave a more long-lasting inhibitory effect on platelet aggregation following intravenous or oral administration. These results coupled with the finding that PGD2 has less hypotensive effects on the cardiovascular system than PGE1 suggest the possible use of PGD2 as an antithrombotic agent. 相似文献
93.
Ian D. Hay Thomas M. Annesley Nai S. Jiang Colum A. Gorman 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1981,226(2):383-390
A method for the determination of d- and l-thyroxine in human serum is described. The method involves extraction of thyroxine from serum and the separation of thyroxine enantiomers on a reversed-phase, high-performance liquid chromatographic column by use of a chiral eluent containing l-proline and cupric sulfate. Satisfactory resolution of the enantiomers of thyroxine, triiodothyronine, and reverse triiodothyronine can be achieved in 12 min and, employing amperometric detection to monitor the separation, the detection limit for serum thyroxine is in the range of 1–3 ng per injected sample. 相似文献
94.
Kinship and friendship are key human relationships. Increasingly, data suggest that people are not less altruistic toward friends than close kin. Some accounts suggest that psychologically we do not distinguish between them; countering this is evidence that kinship provides a unique explanatory factor. Using the Implicit Association Test, we examined how people implicitly think about close friends versus close kin in three contexts. In Experiment 1, we examined generic attitudinal dispositions toward friends and family. In Experiment 2, attitude similarity as a marker of family and friends was examined, and in Experiments 3 and 4, strength of in-group membership for family and friends was examined. Findings show that differences exist in implicit cognitive associations toward family and friends. There is some evidence that people hold more positive general dispositions toward friends, associate attitude similarity more with friends, consider family as more representative of the in-group than friends, but see friends as more in-group than distant kin. 相似文献
95.
96.
Oral Antibiotic Treatment of Mice Exacerbates the Disease Severity of Multiple Flavivirus Infections
97.
Karen L. Thorpe Patricia Gorman Claire Thomas Denise Sheer John Trowsdale Stephan Beck 《Gene》1997,200(1-2):177-183
We have mapped the human ORFX gene to chromosome 9q34 and determined its complete gene structure. Comparison with RING3, the human MHC-linked homologue on 6p21.3, shows the two gene structures to be highly conserved but with an approximate threefold expansion in the ORFX introns. RING3 and ORFX are found to be ubiquitously expressed in human adult and foetal tissues. Evidence suggests that the two genes may have arisen from an ancient duplication in a common ancestral chromosome. 相似文献
98.
Seasonal variation in the resting metabolic rate of male wood mice Apodemus sylvaticus from two contrasting habitats 15 km apart 总被引:2,自引:0,他引:2
N. Corp M. L. Gorman J. R. Speakman 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1997,167(3):229-239
Diurnal and nocturnal resting metabolic rates of winter- and summer-acclimatized adult male wood mice Apodemus sylvaticus from two adjacent populations, 15 km apart, were measured. One population lived in deciduous woodland, and experienced a
narrower daily range of temperatures than the second population, which inhabited maritime sand-dunes. Ambient temperature
and body mass had significant effects on the resting metabolism of mice, excluding winter-acclimatized sand-dune animals where
only temperature explained significant amounts of the observed variation. Only in this latter group could a thermoneutral
zone be determined, with a lower critical temperature of ca. 25 °C and resting metabolism of 0.155 W. Nocturnal resting metabolic
rates were significantly greater than diurnal levels. Winter acclimatization was associated with reductions in thermal conductance
and resting metabolism, thus minimizing energy expenditure at rest. Site differences in thermoregulatory strategies were only
found in winter, thermal conductances remained similar but mice from the sand-dunes had significantly lower metabolic rates
than those from the woodland. Winter acclimatization in wood mice was influenced by factors in addition to photoperiod. Intra-specific
and individual variations in resting metabolism, as shown in this study, potentially have a pronounced effect on the daily
energy expenditure of a free-living animal.
Accepted: 6 September 1996 相似文献
99.
The immunophenotype of HT29 human colon cancer cells implanted into severe combined immunodeficient mice was assessed in primary
tumours and their metastases in the lungs using an indirect immunohistochemical method. After primary tumours were surgically
removed, the metastases were given time to develop, thus paralleling the clinical situation. While vimentin was negative in
both primary and secondary tumours, E-cadherin was present as membrane-bound labelling in the primary tumours only. Whereas
the markers p53, MIB1, PCNA and CEA were consistently positive in both primary and metastatic tumours, CD44 variant 6 and
CA125 were negative in metastases but positive in the primary tumours. There was a significant increase in the percentage
of cells labelled for p53 in the primary tumours compared with the metastases. For the proliferation markers, there was no
significant difference in labelling between primary tumours and metastases for MIB1. Of the cytokeratins examined, CK 20 gave
the strongest and most consistent reaction in both primary and secondary tumours. The results indicate that, for certain immunohistochemical
markers, results are the same in both primary tumours and metastases. Hence, in these cases, antigens that are expressed on
the primary tumour as well as on the metastases can serve as target molecules for immunologically based forms of treatment
of metastases.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
100.
Ian Walker Stephen A Gorman Russell D Cox David I Vernon John Griffiths Stanley B Brown 《Photochemical & photobiological sciences》2004,3(7):653-659
Photodynamic therapy (PDT) is a treatment combining a photosensitiser, molecular oxygen and visible light of characteristic wavelength to produce cytotoxic reactive oxygen species (ROS). Within our centre, a series of phenothiazinium salts were synthesised and initial characterisation studies performed to determine any potential use for PDT. All photosensitisers within the series were shown to have useful spectral properties for PDT, with absorbance lambdamax above 667 nm. The Log P values of the compounds were shown to range from -0.9 to > +2.0. Furthermore, Log P values were shown to be important in determining the site of subcellular localisation and as such the site of photooxidative damage. Derivatives with a Log P value of greater than +1.0 were shown to initially localise to the lysosomes then relocalise throughout the cytoplasm following illumination, whereas compounds with intermediate Log P values (-0.7 to +1.0) all remained lysosomal. Only methylene blue (Log P-0.9) was shown to redistribute to the nucleus upon illumination. Following treatment of RIF-1 cells with each phenothiazinium salt for 1 h and subsequent exposure to 665 nm laser light at a fluence rate of 10 mW cm(-2)(18 J cm(-2)), it was determined that the most potent photosensitiser was 260-fold more potent than methylene blue. Furthermore, the PDT efficacy of the photosensitisers was shown to be related to the level of mitochondrial damage induced directly following illumination. 相似文献