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483.
Urszula M. Marcinkowska Magdalena Mijas Karolina Koziara Nicholas M. Grebe Grazyna Jasienska 《Evolution and human behavior》2021,42(1):35-42
The psychological construct of sociosexuality—one's sexual openness or propensity to engage in uncommitted sexual relationships—has been broadly examined within numerous cultures and mating contexts. Although there is some evidence suggesting that components of sociosexuality, namely behavior, desire and attitude, change within-person, relatively little research has investigated potential sources of such variation. The aim of our study was to explore if the individual components of sociosexuality change across the menstrual cycle, either as a function of cycle phase or ovarian hormones. One hundred and two naturally cycling women, both single and in a committed relationships, completed questions from the the SOI-R (Sociosexuality Revised) questionnaire three times during a menstrual cycle, scheduled to coincide with their early follicular, peri-ovulatory, and luteal phases. Women provided saliva samples and performed luteinizing hormone tests to distinguish between ovulatory and anovulatory cycles. Women reported slightly more openness to uncommitted sexual relationships during the peri-ovulatory session, but significant differences were restricted only to women who exhibited the luteinizing hormone surge. Ovarian hormone concentrations within cycles significantly predicted SOI Attitude and Desire scores, with estradiol positively related, and progesterone negatively related to openness to uncommitted sexuality. These effects were generally modest in size. The results of this study suggest that sociosexuality can vary within short periods of time, such as a single menstrual cycle. 相似文献
484.
Iwona Malicka Katarzyna Siewierska Bartosz Pula Christopher Kobierzycki Dominik Haus Urszula Paslawska Marek Cegielski Piotr Dziegiel Marzena Podhorska-Okolow Marek Wozniewski 《Experimental biology and medicine (Maywood, N.J.)》2015,240(11):1408-1415
The impact of physical activity on carcinogenesis has been demonstrated in many studies. Taking into account the discrepant results of physical exercise on the cell proliferation and apoptosis of breast cancer, we aimed to examine the impact of physical training on N-methyl-N-nitrosourea-(MNU)-induced mammary carcinogenesis. Fifty female rats were divided into four groups according to the intensity of physical activity they undertook. The number of developed tumors, tumor volume, and histopathological diagnoses were noted. Apoptosis and cell proliferation were studied by the number of TUNEL-positive and Ki-67-expressing cells. We demonstrated a statistically significant decrease in the tumor number between all trained groups and the control group. The results were most pronounced in the group with a moderate intensity of training. Moreover, we showed a decrease in tumor volume as training intensity increased, though the differences were not statistically significant. The mean number of TUNEL-positive cancer cells was significantly higher in the training groups than in the control group. These data suggest that physical training, especially of moderate intensity, may alleviate MNU-induced mammary carcinogenesis. The results could suggest that physical exercise-induced apoptosis may be a protective mechanism. 相似文献
485.
Lukasz Wator Urszula Razny Adriana Balwierz Anna Polus Hans G. Joost Grzegorz Dyduch Romana Tomaszewska Aldona Dembinska-Kiec 《Genes & nutrition》2008,3(3-4):177-180
Leptin is prompt to drive angiogenesis, effecting proper vascularisation. Tissue remodeling (including adipose organ) is associated with the angiogenic response. The aim of this study was to investigate the effect of hyperleptinemia on angiogenesis in subcutaneous (s.c.) in vivo matrigel model in mice on a high fat (HF) diet. HF promoted adipose tissue accumulation and biochemical changes resembling metabolic syndrome. However, the impact of this dietary treatment on angiogenesis, measured in s.c. matrigel model was not significant. Changes in leptin concentration were not accompanied by significant angiogenic response. This lack of leptin activity and impaired signal transduction at the molecular level suggests malfunction of the leptin receptor in NZO mice. 相似文献
486.
Tomasz Gortat Michał Kozakiewicz Miłosława Barkowska Urszula Charytonik 《Acta theriologica》2004,49(4):465-477
A field experiment was carried out in two types of forest environment — a relatively homogenous mixed coniferous forest with
low plant species diversity and a reach and spatially differentiated alder wood. Spatial variation in activity of voles was
sampled by placing ink pads and paper inside PVC waterpipes laid in a line on the forest floor. In the first stage of the
experiment, use of space by bank volesClethrionomys glareolus (Schreber, 1780) was analysed without any bait in track collection tubes. In the second stage, we used an attractant in the
form of scent collected from alien bank vole individuals of different sex (males, females), age (juveniles, adults) and physiological
state (sexually active and not active). In the coniferous forest the distribution of number of visits in tracking tubes was
of aggregated character both before and after providing odour of alien individuals. In the alder wood the aggregation level
that had been initially lower than in the coniferous forest increased after providing scent. As a consequence, placing scent
of alien individuals resulted in decreasing differences in animal distribution in both habitats. The results allow also to
the supposition that the reaction to scent depends on sex, age, and the physiological state of the donor. 相似文献
487.
Urszula Kalinowska Magdalena Ma?ecka Bernhard Lippert 《Inorganica chimica acta》2005,358(8):2464-2472
The synthesis of diethyl (pyridin-2-, -3-, -4-ylmethyl)phosphate (2-pmOpe, 3-pmOpe, 4-pmOpe) ligands and their palladium (II) complexes of general formula trans-[PdCl2L2] (L = 2-pmOpe, 3-pmOpe,4-pmOpe) has been described. Pyridine phosphate derivatives were synthesized via the condensation of phosphorochloridic acid diethyl ester with an appropriate pyridinylmethanol in the presence of triethylamine. The compounds have been identified and characterized by IR, far-IR, 1H NMR, 31P NMR, 31P CP-MAS NMR and elemental analyses. The crystal and molecular structures of palladium (II) complexes, i.e., [PdCl2(2-pmOpe)2] and [PdCl2(4-pmOpe)2] determined by the X-ray diffraction method, are presented. In both structures, Pd(II) ions are four-coordinated by two chlorine atoms and two pyridine nitrogen atoms. The geometry of complexes is square-planar and adopt a trans configuration, which is consistent with preparation method. 相似文献
488.
Costs of reproduction are reflected in women's faces: Post‐menopausal women with fewer children are perceived as more attractive,healthier and younger than women with more children 下载免费PDF全文
489.
Males (n=34) and females (n=23) of long-tailed duck (Clangula hyemalis) collected on the southern coast of the Baltic Sea in winter were studied to determine brain tissue concentration of iron
(Fe), zinc (Zn), copper (Cu), manganese (Mn), and cadmium (Cd). There were no significant differences in the concentration
of metals between males and females, except for Cd, the concentration of which in male brains was twice that of the females.
In the brains of 20 birds (41% male and 26% female), the lead (Pb) concentration exceeded 1 μg/g wet wt. In all the duck brains
examined, Spearman correlation coefficients were significant and positive for Zn−Mn, Cu−Mn, Cu−Fe, and Pb−Fe; a negative correlation
was found for Pb−Zn. Additionally, female brains showed a positive correlation between Pb and Fe. The results obtained were
compared with literature data for diving and nondiving anseriforms and birds of other taxa. It seems that concentration of
heavy metals in the brain tissue of birds reflect natural adaptations (e.g., for diving) as well as effects of environmental
pollution. 相似文献