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排序方式: 共有235条查询结果,搜索用时 328 毫秒
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C. Teasdale L. E. Hughes R. H. Whitehead R. G. Newcombe 《Cancer immunology, immunotherapy : CII》1979,6(2):89-99
Summary The assessment of changes in immune competence due to cancer demands carefully controlled studies with simultaneous consideration of other factors such as age, sex, and general ill health. To determine the effect of each factor, immune competence was measured in 112 healthy individuals, 134 patients with benign disease, and 350 patients with cancer (breast, colorectal, and stomach) with a wide spectrum of parameters.In normal subjects, advancing age was associated with a significant reduction in percentage lymphocyte count (LC), absolute and percentage T cell counts, and responses to phytohaemagglutinin (PHA) and pokeweed mitogen (PWM). In patients with benign disease, advancing age was associated with depression of serum IgM levels, absolute and percentage LC, responses to PHA, and delayed cutaneous hypersensitivity (DCH) responses to tuberculin PPD (Mantoux), and dinitrochlorobenzene (DNCB), but elevation of serum IgA levels.No significant sex effects were demonstrated in either group of subjects.The effects of general ill health were determined by comparing individuals in good health (normal subjects and patients with minor benign breast disease) with those who had poor health (patients with significant benign gastrointestinal disease). The latter showed significant depression of DNCB sensitivity and lymphocyte reactivity to PHA, whereas total WBC and LC were significantly elevated.To determine the effects due to cancer, controls were matched for their general state of health and site of disease, in addition to completing all studies prior to any form of therapy. Age differences were corrected for by application of the findings of the above study. This age correction resulted in marked alterations in the significance of observed differences between cancer patients and controls. The previous significance of many differences either disappeared or was reduced, although in two instances significance was attained only after age correction. The only consistent immunodepression observed in the three types of cancer patient tested was impaired reactivity to DNCB. Responses were impaired even in early disease at all three sites.We have shown that the immunodepression exhibited by cancer patients is a summation of the effects due to age, general ill health, and malignancy. Some of the changes previously ascribed to cancer are due to these other factors. 相似文献
3.
T W Teasdale T I S?rensen A J Stunkard 《Human biology; an international record of research》1992,64(1):99-106
In this study we explore the relationships between intelligence test score, educational level, and degree of body fatness. We collected data on intelligence test score, educational level, height, and weight from a sample of 26,274 young Danish men and computed body mass index (weight/height2) as a measure of fatness. Both intelligence test score and educational level had maximum values below the median for body mass index and declined monotonically thereafter. The decline was equal for test score and educational level and above 32 kg/m2 corresponded to almost half a standard deviation. These results are not readily explained by stigmatization of frank obesity, and other mechanisms, possibly genetic, may be responsible. 相似文献
4.
Development and validation of a sensitive immunohistochemical oestrogen receptor assay for use on archival breast cancer tissue 总被引:1,自引:0,他引:1
In a preliminary paper (Teasdale et al. 1987) comparing the oestrogen receptor (ER) content of breast cancers by the biochemical dextran coated charcoal (DCC) method and by two histochemical methods, peroxidase immunocytochemistry (ERICA) and immunogold-silver staining (IGSS), it was indicated that ERICA is more sensitive than DCC and that IGSS is as specific as ERICA but less sensitive. This paper describes the comparison of the above three assay methods with two other biochemical methods, iso-electric focusing (IEF) and an enzyme immuno-assay (EIA) on a larger number of cancers. All methods gave statistically comparable results except that IGSS remained less sensitive than the rest. Various modifications to IGSS showed that an immunogold streptavidin enhancement method (IG-SAM) produced sensitivity and specificity equal to that of ERICA. Since IGSS and its modifications are the only methods which can be used on archival paraffin-embedded cancers and IG-SAM gives results highly comparable to ERICA, retrospective studies can be performed on patients whose outcome and response to various treatments are known. Most recent studies have shown that ER positive results can be obtained from 10-year-old paraffin blocks. 相似文献
5.
Summary A method of localising oestrogen receptor in nuclei of breast cancer cells by the protein A-gold technique is described. Mast cell granules were found to take up uncoated particles of the gold sol selectively. 相似文献
6.
Boron deficiency in cultured pine cells : quantitative studies of the interaction with ca and mg 总被引:4,自引:2,他引:2 下载免费PDF全文
A pronounced interaction between calcium, magnesium, and boron was found in growth studies with Pinus radiata cell cultures. Quantitative isoactivity data for the interaction was analyzed in terms of selected simple and plausible theoretical models. The data was found to be consistent with a model in which a critical acceptor molecule is activated only by binding both Ca and B at separate sites; Mg competitively displaces Ca to inactivate the acceptor. It was found that B is, surprisingly, not bound strongly (Kdiss = 450 ± 80 micromolar) and that the affinity for Ca is two orders of magnitude stronger than for Mg. Therefore only a small proportion of the acceptor will be boronated under natural conditions. Moderate levels of mannitol were found to aggravate B deficiency due to its effective removal by direct chemical complexation. At higher concentrations of mannitol (or other sugars), where osmotic contribution is significant, little B was needed to overcome growth inhibition—a result consistent with B having a primary role in cell wall biosynthesis. 相似文献
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Dr AR Holmes RD Cannon HF Jenkinson 《Journal of industrial microbiology & biotechnology》1995,15(3):208-213
The yeastCandida albicans coaggregates with a variety of streptococcal species, an interaction that may promote oral colonization by yeast cells.C. albicans andCandida tropicalis are the yeasts most frequently isolated from the human oral cavity and our data demonstrate that both these species bind toStreptococcus gordonii NCTC 7869 while two otherCandida species (Candida krusei andCandida kefyr) do not. Adherence ofC. albicans was greatest when the yeast had been grown at 30° C to mid-exponential growth phase. For 21 strains ofC. albicans there was a positive correlation between the ability to adhere toS. gordonii and adherence to experimental salivary pellicle. Whole saliva either stimulated or slightly inhibited adherence ofC. albicans toS. gordonii depending on the streptococcal growth conditions. The results suggest that the major salivary adhesins and coaggregation adhesins ofC. albicans are co-expressed. 相似文献
9.
R Fathi Q Huang G Coppola W Delaney R Teasdale A M Krieg A F Cook 《Nucleic acids research》1994,22(24):5416-5424
Oligonucleotide (2-aminoethyl)phosphonates in which the backbone consisted of isomerically pure, alternating (2-aminoethyl)-phosphonate and phosphodiester linkages have been prepared and characterized. One of these single isomer oligonucleotides (Rp) formed a more stable duplex with DNA or RNA than its corresponding natural counterpart. Hybrid stability was more pH-dependent, but less salt-dependent than a natural duplex. The specificity of hybridization was examined by hybridization of an oligonucleotide containing one (2-aminoethyl)phosphonate to oligonucleotides possessing mismatches in the region opposite to the aminoethyl group. In contrast to oligonucleotides containing (aminomethyl)-phosphonate linkages, oligonucleotide (2-aminoethyl)phosphonates were completely stable to hydrolysis in aqueous solution. These oligonucleotides were resistant to nuclease activity but did not induce RNase H mediated cleavage of a complementary RNA strand. Incubation in a serum-containing medium resulted in minimal degradation over 24 hours. Studies of cell uptake by flow cytometry and confocal microscopy demonstrated temperature dependent uptake and intracellular localization. (2-Aminoethyl)phosphonates represent a novel approach to the introduction of positive charges into the backbone of oligonucleotides. 相似文献
10.
The signal for Golgi retention of bovine beta 1,4-galactosyltransferase is in the transmembrane domain. 总被引:9,自引:0,他引:9
The expression and localization of bovine beta 1,4-galactosyltransferase (Gal T) has been studied in mammalian cells transfected with Gal T cDNA constructs, and the role of the amino-terminal domains of Gal T in Golgi localization examined. Here we demonstrate that the transmembrane (signal/anchor) domain of bovine Gal T contains a positive Golgi retention signal. Bovine Gal T was characterized in transfected cells with anti-bovine Gal T antibodies, affinity-purified from a rabbit antiserum using a bacterial recombinant fusion protein. These affinity-purified antibodies recognized native bovine Gal T and showed minimum cross-reactivity with Gal T from non-bovine sources. Bovine Gal T cDNA was expressed, as active enzyme, transiently in COS-1 cells and stably in murine L cells, and the product was shown to be localized to the Golgi complex by immunofluorescence using the polypeptide-specific antibodies. A low level of surface bovine Gal T was also detected in the transfected L cells by flow cytometry. The removal of 18 of the 24 amino acids from the cytoplasmic domain of bovine Gal T did not alter the Golgi localization of the product transiently expressed in COS-1 cells or stably expressed in L cells. Both the full-length bovine Gal T and the cytoplasmic domain deletion mutant were N-glycosylated in the transfected L cells, indicating both proteins have the correct N(in)/C(out) membrane orientation. Deletion of both the cytoplasmic and signal/anchor domains of bovine Gal T and incorporation of a cleavable signal sequence resulted in a truncated soluble bovine Gal T that was rapidly secreted (within 1 h) from transfected COS-1 cells. Replacement of the signal/anchor domain of bovine Gal T with the signal/anchor domain of the human transferrin receptor resulted in the transport of the hybrid molecule to the cell surface of transfected COS-1 cells. Furthermore, a hybrid construct containing the signal/anchor domain of Gal T with ovalbumin was efficiently retained in the Golgi complex, whereas ovalbumin anchored to the membrane by the transferrin receptor signal/anchor was expressed at the cell surface of transfected COS-1 cells. Overall, these studies show that the hydrophobic, signal/anchor domain of Gal T is both necessary and sufficient for Golgi localization. 相似文献