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Age comparative content anaylses were carried out for eleven support-discussion groups. Comparisons of six groups of elderly persons and five groups of college youth revealed that the older more frequently discuss bodily changes, family relations, significant others and external sources of self respect. The young were more concerned with physical vulnerabilities. The elderly were more likely to discuss matters in terms of the past. The results are considered in the light of a life stage developmental conception of group behavior which could have implications for helping interventions. 相似文献
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Induction of proliferation of B prolymphocytic leukemia cells by phorbol ester and native or recombinant interferon-gamma 总被引:1,自引:0,他引:1
Phorbol ester phorbol myristate acetate (PMA) induces proliferation in nonmalignant human B cells and B cells from a patient with B prolymphocytic leukemia (B-PLL). Mitogen-free T cell-derived conditioned medium acts synergistically with PMA in inducing proliferation of B-PLL cells but does not enhance the PMA-stimulated outgrowth of nonmalignant B cells. Interleukin 2 (IL-2) has no effect on the outgrowth of B-PLL cells, and monoclonal antibodies against the IL-2 receptor do not influence the response to PMA and conditioned medium. Recombinant interferon-gamma (IFN-gamma), in contrast, is a potent enhancer of PMA-induced proliferation of B-PLL cells. With gel filtration techniques and with the use of anti-IFN-gamma antibodies, it is shown that IFN-gamma in the conditioned medium is responsible for the observed increase in B-PLL cell proliferation. Preincubation of B- PLL cells with IFN-gamma induces responsiveness to PMA, whereas IFN- gamma alone had no effect on these cells when pretreated with PMA. The combined data show that, in the presence of PMA, native and recombinant IFN-gamma are growth factors for B cells from a B-PLL patient and that IL-2 is not involved in this process. 相似文献
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BRCA1 and BRCA2 are major breast cancer susceptibility genes. Nineteen single nucleotide polymorphisms (SNPs) at 18 loci have been associated with breast cancer. We aimed to determine whether these predict breast cancer incidence in women with BRCA1/BRCA2 mutations. BRCA1/2 mutation carriers identified through the Manchester genetics centre between 1996 and 2011 were included. Using published odds ratios (OR) and risk allele frequencies, we calculated an overall breast cancer risk SNP score (OBRS) for each woman. The relationship between OBRS and age at breast cancer onset was investigated using the Cox proportional hazards model, and predictive ability assessed using Harrell's C concordance statistic. In BRCA1 mutation carriers we found no association between OBRS and age at breast cancer onset: OR for the lowest risk quintile compared to the highest was 1.20 (95% CI 0.82–1.75, Harrell's C = 0.54), but in BRCA2 mutation carriers the association was significant (OR for the lowest risk quintile relative to the highest was 0.47 (95% CI 0.33–0.69, Harrell's C = 0.59). The 18 validated breast cancer SNPs differentiate breast cancer risks between women with BRCA2 mutations, but not BRCA1. It may now be appropriate to use these SNPs to help women with BRCA2 mutations make maximally informed decisions about management options. 相似文献
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High resolution of heterogeneity among human neutrophil granules: physical, biochemical, and ultrastructural properties of isolated fractions 总被引:4,自引:1,他引:4
Previous studies on the fractionation of human neutrophil granules have identified two major populations: myeloperoxidase (MPO)-containing azurophil, or primary, granules and MPO-deficient specific, or secondary, granules. Peripheral blood neutrophils from individual donors were lysed in sucrose-free media by either hypotonic shock or nitrogen cavitation. Using a novel two-gradient Percoll density centrifugation system, the granule-rich postnuclear supernatant was rapidly (ten minutes) and reproducibly resolved into 13 granule fractions (L1 through L8 and H1 through H5). Granule flotation and recentrifugation experiments on both continuous, self-generated and multiple-step gradients using individual and mixed isolated fractions demonstrated that the banding patterns were isopycnic and nonartifactual. Isolated granules were intact based on the findings that biochemical latency of several granule enzymes was greater than 95%, and thin-sectioned electron micrographs demonstrated intact granule profiles. Biochemical analyses of the granule marker proteins MPO, beta-glucuronidase, lysozyme, and lactoferrin indicated that a number of the fractions were related to the major azurophil and specific granule populations. Lactoferrin was found in ten of 13 fractions (L1 through L8, H1 to H2), whereas MPO was found in every fraction. Consistent with these biochemical data, all fractions exhibited varying degrees of heterogeneity based on ultrastructural morphology and cytochemistry, including diaminobenzidine (DAB) reactivity for peroxidase and periodate-thiocarbohydrazide-silver proteinate (PA-TCH-SP) staining for complex glycoconjugates. A variable but significant percentage (23% to 70%) of the granules in fractions L1 through L8 and H1 and H2 showed DAB reactivity, while about 90% of the granules in fractions H3 through H5 were peroxidase positive. These results demonstrated that DAB-reactive granules spanned the entire range of granule size and density. Ultrastructural PA-TCH-SP staining of isolated granule fractions revealed patterns similar to those of granules in intact neutrophils at different stages of development. Granules from human acute promyelocytic leukemia cells (HL-60) exhibited a surprisingly low density compared with typical azurophil granules from normal, mature neutrophils. The data suggest that both functional and maturational differences contribute to granule heterogeneity, and provide a new practical and conceptual framework for further defining the phenomenon of neutrophil granule heterogeneity. 相似文献
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Steinmann D Maertens B Janssen S Werner M Frühauf J Nakamura M Christiansen H Bremer M 《Journal of cancer research and clinical oncology》2012,138(9):1523-1529
Purpose
Standard treatment of single brain metastases so far is tumour resection in combination with postoperative whole-brain radiotherapy or stereotactic radiosurgery. Here, we report retrospectively our first experience with postoperative hypofractionated stereotactic radiotherapy (hfSRT) to the resection cavity in order to replace upfront WBRT with respect to treatment efficacy and safety.Methods
Between March 2006 and October 2011, 33 patients with a single newly diagnosed intracranial metastasis were treated with hfSRT following microsurgical resection. Fractionation concepts were 10?×?4?Gy (n?=?22), 7?×?5?Gy (n?=?7) and 5?×?6?Gy (n?=?4). Planning target volume enclosed the tumour resection cavity with a safety margin of 4?mm.Results
No patient demonstrated toxicity grade 2 or higher. Actuarial median overall survival summed up to 20.2?months, and 12-month survival was 64?%. Actuarial mean local brain control was 30.6?months, median distant brain control 12.4?months and intracranial control 8.8?months, respectively. Actuarial 1-year rates of local, distant brain and intracranial control were 71, 57 and 43?%. Salvage whole-brain radiotherapy due to recurrent brain metastases was performed in 13 patients (39?%).Conclusion
Postoperative hfSRT appears to be a feasible treatment option in patients with a single newly diagnosed brain metastasis. Replacing the standard postoperative whole-brain radiotherapy necessitates compliant patients and regular MRI follow-up analysis. 相似文献30.
Anders Åsberg Karsten Midtvedt Mike van Guilder Elisabet Størset Sara Bremer Stein Bergan Roger Jelliffe Anders Hartmann Michael N. Neely 《Transplant international》2013,26(12):1198-1207
Following organ engraftment, initial dosing of tacrolimus is based on recipient weight and adjusted by measured C0 concentrations. The bioavailability and elimination of tacrolimus are affected by the patients CYP3A5 genotype. Prospective data of the clinical advantage of knowing patient's CYP3A5 genotype prior to transplantation are lacking. A nonparametric population model was developed for tacrolimus in renal transplant recipients. Data from 99 patients were used for model development and validation. A three‐compartment model with first‐order absorption and lag time from the dosing compartment described the data well. Clearances and volumes of distribution were allometrically scaled to body size. The final model included fat‐free mass, body mass index, hematocrit, time after transplantation, and CYP3A5 genotype as covariates. The bias and imprecision were 0.35 and 1.38, respectively, in the external data set. Patients with functional CYP3A5 had 26% higher clearance and 37% lower bioavailability. Knowledge of CYP3A5 genotype provided an initial advantage, but only until 3‐4 tacrolimus concentrations were known. After this, a model without CYP3A5 genotype predicted just as well. The present models seem applicable for clinical individual dose predictions but need a prospective evaluation. 相似文献