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741.
Humoral and cellular immune reactions against tumor cells in patients with urinary bladder carcinoma 总被引:1,自引:0,他引:1
Hansson Yngve Paulie Staffan Larsson Åke Lundblad Marie-Louise Perlmann Peter Näslund Ingemar 《Cancer immunology, immunotherapy : CII》1983,16(1):23-29
Serum IgG fractions from a large and homogeneous group of patients with transitional cell carcinoma of the urinary bladder (TCC) were tested for their capacity to induce antibody-dependent cellular cytotoxicity (ADCC) with lymphocytes from healthy donors against a TCC-derived target cell and one derived from adenocarcinoma of the colon. Both targets have previously been shown to be of comparable susceptibility to cell-mediated lysis in vitro. Some of the IgG preparations showed strong and dose-dependent ADCC against either one or both targets, while others gave weak reactions or none at all. Similar results were obtained with IgG from a matched group of patients with prostatic carcinoma who were used as clinical controls (CC). In parallel experiments, lymphocytes taken from the two donor groups at the same time as the serum samples were tested for their direct cytotoxicity (CMC) against the two targets. CMC gave similar results to ADCC. The differences in cytotoxicity displayed by either IgG or lymphocytes from individual donors were analysed statistically, using nonparametric statistics. To avoid introducing bias due to arbitrary data selection, the entire set of results, comprising both high and low reactors, was included in the statistical assessment. ADCC of the TCC donors' IgG against the TCC target was significantly stronger than against the colon carcinoma and also significantly stronger than that of the control donors. Similarly, the TCC patients' lymphocytes displayed a significantly higher CMC against the TCC target than against the control targets. This was not seen when the lymphocytes from the patients with prostatic carcinoma were tested. When CMC and ADCC of individual donors were compared, a statistically significant correlation between these activities was seen in three of the four donor/target combinations. These results support earlier findings and suggest that a significant fraction of both the disease-related and the 'non-selective' CMC (NK) displayed by cancer patients lymphocytes against allogeneic tumor cells in vitro reflects antibody-dependent reactions. 相似文献
742.
Rehbinder C. Edqvist L.-E. Riesten-Århed U. Nordkvist M. 《Acta veterinaria Scandinavica》1981,22(3-4):355-359
Peripheral blood plasma levels of progesterone were studied in pregnant and non-pregnant reindeer. Marked differences in progesterone levels were found between pregnant and non-pregnant animals indicating that the determination of progesterone could be used as a pregnancy diagnosis test in reindeer. 相似文献
743.
Åsa Berggren 《Insect Science》2010,17(5):400-405
Abstract Despite the growing interest in how an individual's immune response is correlated to morphological and ecological factors, little empirical data has been available from wild insect populations. Many insects have different color morphs and exhibit differences in immune responses. Links are expected to exist between body colors and immune function in insects, because the same biochemical precursors involved in the immune response are responsible for melanin-based color markings. In this study, I assay the immune response of two different color morphs of 377 wild-caught bush-crickets, Metrioptera roeseli, from 20 populations by measuring individual encapsulation responses to a surgically implanted nylon monofilament. There was no difference between green and brown bush-cricket morphs (low melanin vs high melanin investment in cuticula color respectively) and their ability to mount an immune response to the implant. Further study is needed on the relationship between color morphology and immune response in wild insects, and whether trade-offs occur between factors during an insect's development phase and long-term health. 相似文献
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746.
In two previous studies influence of gonadal hormones on male—female interaction has been investigated. Interaction between pair-living cagemates and non-cagemates was compared. In the first study the animals met in direct paired encounters, and in the second study the tested animals had the choice of wiremesh-restricted contact with the cagemate or a non-cagemate. The present choice test involves direct contact with the animal chosen in a series of consecutive trials. The two incentive animals were again non-cagemate and the cagemate of the experimental animal. The males tested were intact or castrated. The females were tested in induced oestrus. The females tested with intact males showes a higher choice of the cagemate. This was also the case in castrated males. Intact males and females tested with castrated males showed no significant difference in their choice. Differences in the results and testing conditions of the present and the previous choice test allowing restricted contact are discussed. 相似文献
747.
Hans-Erik Åkerlund 《Journal of biochemical and biophysical methods》1984,9(2):133-141
An apparatus is described that reduces the time required for counter-current distribution in aqueous polymer two-phase systems by a factor of more than five. Phase settling, which has been the time consuming step, is here facilitated by centrifugation. The crucial point in the construction, that allows automatization, is that the transfer step in the counter-current distribution cycle is performed during centrifugation. 相似文献
748.
Eirunn Thun Bjørn Bjorvatn Torbjørn Åkerstedt Bente Elisabeth Moen Siri Waage Helge Molde 《Chronobiology international》2016,33(5):480-489
Numerous cross-sectional studies report high prevalence rates of sleepiness and insomnia in shift workers, but few longitudinal studies exist. We investigated trajectories of sleepiness and insomnia symptoms in a sample of Norwegian nurses across four measurements, spanning a total of four years (sleepiness) and five years (insomnia). The participants completed the Epworth Sleepiness Scale and the Bergen Insomnia Scale at each measurement instance. Latent growth curve models were used to analyse the data. Separate models examined night work (night work, entering and leaving night work) and rotational work (rotational work, entering and leaving rotational work) as predictors for trajectories of sleepiness and insomnia symptoms, respectively. Baseline values of sleepiness and insomnia were higher among rotational shift workers than among workers with fixed shifts (day or night). The results showed that night work throughout the period and entering night work during the period were not associated with different trajectories of sleepiness or insomnia symptoms, compared to not having night work. The same results were found for rotational work and entering rotational work, compared to not having rotational work. Leaving night work and leaving rotational work were associated with a decrease in sleepiness and insomnia symptoms, compared to staying in such work. 相似文献
749.
Jens Brøbech Legarth Stellan Åkesson Alena Ashkin Anne -Marie Imrell 《The International Journal of Life Cycle Assessment》2000,5(1):47-58
The screening level LCA places itself amongst the many approaches to LCA, including full LCA and streamlined LCA. The screening
level LCA combines the quantitative nature of the full LCA with the low effort of the streamlined LCA. This paper presents,
as an example, a screening level LCA of the EU 2000 air handling unit from ABB Ventilation Products AB, Sweden, using the
Danish EDIP impact assessment method, the EDIP software and database. This study proved that major improvement potentials
can indeed be identified with screening level LCA, and argues that the screening level LCA is a suitable approach in the early
stages of a company’s life cycle engineering efforts
Contact for the screening level LCA method Corresponding author at ABB Corporate Research 相似文献
750.
Hair zinc and copper: Relationship to hair type and serum concentrations in children and adolescents
The zinc and copper serum and hair concentrations of 691 3-18-y-old girls and boys previously determined as a part of the
Multicentre Study of Atherosclerosis Precursors in Finnish Children and Adolescents were further analyzed in order to find
a possible association between these two zinc and copper indices. The influence of hair color and the diameter of individual
hair strands on hair concentrations were studied by the analysis of covariance. Hair color and serum zinc concentrations were
found to be associated with hair zinc concentrations in boys. Such an association was not found for zinc and copper concentrations
in girls. Hair vs serum concentrations in different age and hair color groups did not show however, a significant relationship
either in copper or in zinc concentrations. The subjects with very low or high serum zinc or copper concentrations did not
usually have extreme hair concentrations and vice versa. However, there were some subjects with low or high serum concentrations
associated with low or high hair concentrations. 相似文献