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1.
Ernest I. Onyishi Piotr Sorokowski Agnieszka Sorokowska R. Nathan Pipitone 《Evolution and human behavior》2012,33(6):771-774
Previous research has demonstrated that having more children decreases marital satisfaction among parents. However, the universality of these findings is limited since the vast majority of the studies have been conducted in Western countries. In the present study, 374 people from the Igbo ethnic group (Nigeria) were assessed for levels of marital satisfaction and the number of children. In contrast to almost all previous findings, we found a positive relationship between the number of children and marital satisfaction among parents. Number of children was the strongest predictor of marital satisfaction even when compared to other variables like wealth and education. Our results suggest that the negative relationship between the number of children and marital satisfaction is not culturally universal and probably only characterizes developed, individualistic Western countries. We discuss our findings from a sociocultural and evolutionary perspective. 相似文献
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Tadeusz Janas Agnieszka Janiak-Osajca Teresa Janas 《Journal of biological physics》1995,21(4):295-306
The application of the theory of homeomorphic transformations of topological manifolds and the operation of the connected sum of manifolds for a formation of a topological model of membrane transformations during the division process of cellular and subcellular compartments, has been shown. The biological cell and the subcellular structures in the form of vesicles are modelled by an arrangement of two concentric spheres corresponding to the inner and outer layer of the membrane bounding the vesicle. The analysis shows eight succeeding topological stages of membrane transformations during the division process and these stages are characterised. It is concluded that there is a vectorial translocation of lipid molecules from the inner layer of the membrane bounding the vesicle before the division process to the outer layer of the membranes after the division process and there is no lipid translocation from the outer layer to the inner layers during the division process. 相似文献
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Zinc and cadmium analysis in human prostate neoplasms 总被引:4,自引:0,他引:4
Magdalena Brys Agnieszka D. Nawrocka Eügeniüsz MlekoŚ Cezary Zydek Marek Foksinski Andrzej Barecki Wanda M. Krajewska 《Biological trace element research》1997,59(1-3):145-152
The objective of this study was to test the hypothesis that prostatic cancer is associated with the changes of zinc (Zn) and
cadmium (Cd) concentration. Normal prostate, benign prostatic hyperplasia (BPH), and prostatic carcinoma (PCA) were analyzed
for Zn and Cd by atomic absorption spectrometry. Cd level was measured using a graphite furnace and Zn level was measured
by flame mode. Metal content was assessed in whole tissues and in nuclear, plasma membrane, and cytosolic fractions. An increase
of Zn content in BPH, but a decrease in PCA as compared to normal tissue, was observed. Cd concentration appeared to be higher
in BPH and PCA than in normal tissue. No correlation between Zn and Cd level was found in BPH specimens obtained from the
same patients. Probability values ofp ≤0.05 were considered to indicate significant differences. Obtained results seem to support the hypothesis of Cd carcinogenicity
and preventing function of Zn in prostatic cancer. Plasma membrane fraction corresponding to lysosomal, mitochondrial, and
microsomal subcellular compartments are probably critical in Zn and Cd participation in human prostate neoplasms. 相似文献
7.
Alexander Knight Nicholas R Leslie Agnieszka Zagozdzon Roderick Bronson Yefim Manevich Craig Beeson Carola A Neumann 《The EMBO journal》2009,28(10):1505-1517
It is widely accepted that reactive oxygen species (ROS) promote tumorigenesis. However, the exact mechanisms are still unclear. As mice lacking the peroxidase peroxiredoxin1 (Prdx1) produce more cellular ROS and die prematurely of cancer, they offer an ideal model system to study ROS‐induced tumorigenesis. Prdx1 ablation increased the susceptibility to Ras‐induced breast cancer. We, therefore, investigated the role of Prdx1 in regulating oncogenic Ras effector pathways. We found Akt hyperactive in fibroblasts and mammary epithelial cells lacking Prdx1. Investigating the nature of such elevated Akt activation established a novel role for Prdx1 as a safeguard for the lipid phosphatase activity of PTEN, which is essential for its tumour suppressive function. We found binding of the peroxidase Prdx1 to PTEN essential for protecting PTEN from oxidation‐induced inactivation. Along those lines, Prdx1 tumour suppression of Ras‐ or ErbB‐2‐induced transformation was mediated mainly via PTEN. 相似文献
8.
Ewelina Grywalska Jacek Roliński Marcin Pasiarski Izabela Korona-Glowniak Maciej Maj Agata Surdacka Agnieszka Grafka Agnieszka Stelmach-Go?dy? Micha? Zgurski Stanis?aw Gó?d? Anna Malm Piotr Grabarczyk El?bieta Staros?awska 《PloS one》2015,10(10)
Epstein-Barr virus (EBV) is a ubiquitous γ-herpesvirus that infects more than 90% of the world population. The potential involvement of EBV in the clinical course of chronic lymphocytic leukemia (CLL) remains unexplained. The aim of this study was to determine whether EBV-DNA load in the peripheral blood mononuclear cells (PBMCs) of CLL patients may influence heterogeneity in the course of the disease. The study included peripheral blood samples from 115 previously untreated patients with CLL (54 women and 61 men) and 40 healthy controls (16 women and 24 men). We analyzed the association between the EBV-DNA load in PBMCs and the stage of the disease, adverse prognostic factors, and clinical outcome. Detectable numbers of EBV-DNA copies in PBMCs were found in 62 out of 115 CLL patients (53.91%). The EBV-DNA copy number/μg DNA was significantly higher in patients who required early implementation of treatment, presented with lymphocyte count doubling time <12 months, displayed CD38-positive or ZAP-70-positive phenotype, and with the del(11q22.3) cytogenetic abnormality. Furthermore, the EBV-DNA copy number/μg DNA showed significant positive correlation with the concentrations of lactate dehydrogenase (LDH) and beta-2-microglobulin. We have shown that in CLL patients, higher EBV-DNA copy number predicted shorter survival and shorter time to disease progression, and it was associated with other established unfavorable prognostic factors. This suggests that EBV may negatively affect the outcome of CLL. 相似文献
9.
In Arabidopsis the in vitro culture of immature zygotic embryos (IZEs) at a late stage of development, on the solid medium containing synthetic
auxin, leads to formation of somatic embryos via direct somatic embryogenesis (DSE). The presented results provide evidence
that in IZE cells competent for DSE are located in the protodermis and subprotodermis of the adaxial side of cotyledons and
somatic embryos displayed a single- or multicellular origin. Transgenic Arabidopsis lines expressing the GUS reporter gene, driven by the DR5 and LEC2 promoters, were used to analyse the distribution of auxin to mark embryogenic cells in cultured explants and develop somatic
embryos. The analysis showed that at the start of the culture auxin was accumulated in all explant tissues, but from the fourth
day onwards its location shifted to the protodermis and subprotodermis of the explant cotyledons. In globular somatic embryos
auxin was detected in all cells, with a higher concentration in the protodermis, and in the heart stage its activity was mainly
displayed in the shoot, root pole and cotyledon primordia. The embryogenic nature of dividing protodermal and subprotodermal
cells accumulating auxin was confirmed by high expression of promoter activity of LEC2 in these cells. Analysis of symplasmic tracer (CFDA) distribution indicated symplasmic isolation between tissues engaged
in DSE and other parts of an explant. Symplasmic isolation of somatic embryos from the explant was also detected. 相似文献
10.
Buszewska ME Strzelecka-Kiliszek A Tylki-Szymańska A Bandorowicz-Pikuła J 《Postepy biochemii》2007,53(2):169-173
Niemann-Pick disease is a genetic disorder, affecting approximately 1 to 150,000 living births per year; in Poland 1-5 cases. Usually diagnosed in the childhood, Niemann-Pick disease results in death in the teenage years. Niemann-Pick disease is defined as a lysosomal storage disorder and is related to impaired transport and/or accumulation of specific lipids inside the cell. In this report, we provide evidence about potential role of annexins, calcium- and membrane-binding proteins, in the formation and stabilization of cholesterol-rich microdomains and their possible function in organizing the membranes of early and late endosomes, organelles affected in the type C Niemann-Pick disease characterized by abnormal accumulation of cholesterol and glycosphingolipids in lysosomal like organelles. 相似文献