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101.
102.
Ecotoxicological characteristics and ecological risk assessment of trace elements in the bottom sediments of the Rożnów reservoir (Poland) 总被引:1,自引:0,他引:1
Szara Magdalena Baran Agnieszka Klimkowicz-Pawlas Agnieszka Tarnawski Marek 《Ecotoxicology (London, England)》2020,29(1):45-57
Ecotoxicology - The bottom sediments in catchment areas behind dams play a significant role in water ecosystems. On the other hand, the structure of sediments makes them a natural geosorbent, in... 相似文献
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Marek Strzala Arkadiusz Stanula Grzegorz G?ab Jacek Glodzik Andrzej Ostrowski Marcin Kaca Leszek Nosiadek 《Journal of Sports Science and Medicine》2015,14(1):110-117
The aim of this study was to investigate somatic properties and physiological capacity, and analyze kinematic parameters in the 200 m breaststroke swimming race. Twenty-seven male swimmers participated in the study. They were 15.7±1.98 years old. Their average height was 1.80 ± 0.02 m and lean body mass (LBM) was 62.45 ± 8.29 kg. Physiological exercise capacity was measured in two separate 90 sec. all-out tests, one for the arms and second for legs. During the tests total work of arm cranking (TWAR) and cycling (TWLG) as well as peak of VO2 for arm (VO2peakAR) and leg (VO2peakLG) were measured. The underwater swimmers body movements were recorded during the all-out swimming 200m breaststroke speed test using an underwater camera installed on a portable trolley. The swimming kinematic parameters and propulsive or non-propulsive movement phases of the arms and legs as well as average speed (V200), surface speed (V200surface) and swimming speed in turn zones (V200turns) were extracted. V200surface was significantly related to the percentage of leg propulsion and was shown to have large effect on VO2peakLG in the Cohen analysis. V200turns depended significantly on the indicators of physiological performance and body structure: TWAR, VO2peak LG and LBM, LBM, which in turn strongly determined the measured results of TWAR, TWLG, VO2peakAR and VO2peakLG. The V200turns and V200surface were strongly associated with V200, 0.92, p < 0.001 and 0.91, p < 0.001 respectively. In each lap of the 200m swimming there was an increased percentage of propulsion of limb movement observed simultaneously with a reduction in the gliding phase in the breaststroke cycles.
Key points
- This study investigated the influence of the selected indicators of somatic properties and physiological capacity as well kinematic and coordination parameters on breaststroke swimming.
- In this observations the body’s functional capacity have an important impact on achieving good breaststroke swimming results, the V200 was moderately associated on VO2peakLG, moreover, separate V200turns depended with VO2peakLG and on LBM and TWAR.
- The speed of surface breaststroke swimming - V200surface similarly as V200turns had a very strong influence on the end result of V200 , 0.91, p<0.001 and 0.92, p<0.001 respectively.
- The ability to swim fast on the surface (V200surface) was positively and significantly associated with the percentage time of propulsion generation -LP in the breaststroke cycle.
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Marek Pawlikowski Maria Jaranowska Hanna Pisarek Robert Kubiak Julita Fuss-Chmielewska Katarzyna Winczyk 《Archives of Medical Science》2015,11(6):1314-1317
Introduction
In normal conditions follicle-stimulating hormone receptors (FSHR) are expressed in the ovary and the testis. They can also be expressed in gonadal tumors. However, recently we have found FSHR immunostaining in pituitary adenomas, adrenal tumors and neuroendocrine tumors (carcinoids). The aim of this study was to determine whether the same occurs in thyroid tumors.Material and methods
Thirty-six samples of surgically excised thyroids were examined. Follicle-stimulating hormone receptors immunostaining was performed on paraffin sections using the rabbit anti-human FSHR polyclonal antibody raised against a 1-190 amino acid sequence from the human FSHR (sc-13935, Santa Cruz).Results
Normal thyroid follicles do not show immunopositivity for FSHR. The same concerns the majority of benign lesions, diagnosed as hyperplasia nodularis or thyroid adenomas. However, positive FSHR immunostaining in some follicles was observed. In all but one thyroid cancer (15 papillary, 10 follicular cancers and one case of anaplastic thyroid cancer) 10–100% of tumor cells exhibit positive FSHR immunostaining. In about 40% of samples FSHR immunoreactivity can be observed also in the endothelia of intrathyroidal blood vessels. This immunopositivity was more frequent in the samples of thyroid cancers (13/27) than in benign lesions (2/9).Conclusions
Ectopic positive FSHR immunostaining is also present in thyroid cancers, and, to a lesser degree, in benign lesions but not in the normal thyroid epithelium. 相似文献108.
A MicroRNA-Based Test Improves Endoscopic Ultrasound–Guided Cytologic Diagnosis of Pancreatic Cancer
Randall E. Brand Alex T. Adai Barbara A. Centeno Linda S. Lee George Rateb Shivakumar Vignesh Charles Menard Anna Wiechowska–Kozłowska Hubert Bołdys Marek Hartleb Michael K. Sanders Johanna B. Munding Andrea Tannapfel Stephan A. Hahn Ludomir Stefańczyk Gregory J. Tsongalis David C. Whitcomb Darwin L. Conwell Jean A. Morisset Timothy B. Gardner Stuart R. Gordon Arief A. Suriawinata Maura B. Lloyd Dennis Wylie Emmanuel Labourier Bernard F. Andruss Anna E. Szafranska–Schwarzbach 《Clinical gastroenterology and hepatology》2014,12(10):1717-1723
109.
Ewelina Kosicka Marek Borowiec Marcin Kowalczuk Aneta Krzyzak Robert Szczepaniak 《Materials》2020,13(23)
In this research, an analysis of polymer composite with the matrix of L285-cured hardener H286 and six reinforcement layers of carbon fabric GG 280 T was provided. It involved a comparison of the dynamical behavior responses for three cases of composite structures in the context of the presence of the mass share modifier. The samples with the addition of a physical modifier with varying mass percentages were investigated by being subjected to dynamic tests with specific parameters, i.e., constant excitation amplitude and vibration frequency in the vicinity of the base resonance zone. The analysis allowed for indicating the relationship between the composition of the prepared composites and their dynamic response via stiffness characteristics. In addition, the investigation resulted in determining the range of harmful dynamical operating conditions, which may contribute to damage to the composite structures. 相似文献
110.
Agnieszka Zagrska Anna Partyka Adam Bucki Marcin Koaczkowski Magdalena Jastrzbska‐Wisek Anna Czopek Agata Siwek Monika Guch‐Lutwin Marek Bednarski Marek Bajda Jakub Joczyk Kamil Piska Paulina Koczurkiewicz Anna Wesoowska Maciej Pawowski 《Chemical biology & drug design》2019,93(4):511-521
A series of 2‐pyrimidinyl‐piperazinyl‐alkyl derivatives of 1H‐imidazo[2,1‐f]purine‐2,4(3H,8H)‐dione has been synthesized in an attempt to discover a new class of psychotropic agents. Compounds were evaluated for their in vitro affinity for serotonin 5‐HT1A, 5‐HT7, and phosphodiesterases PDE4 and PDE10. The most potent compound 2‐pyrimidinyl‐1‐piperazinyl‐butyl‐imidazo[2,1‐f]purine‐2,4‐dione ( 4b ) behaved as strong and selective antagonist of 5‐HT1A. Molecular modeling studies revealed differences in binding mode between compound 4b and buspirone, which might reflect variation of the ligands’ affinity and potency in the 5‐HT1A receptor. Compound 4b in silico models demonstrated drug‐likeness properties and, contrary to buspirone, showed a metabolic stability in mouse liver microsomes system. Experimentally obtained value of apparent permeability coefficient Papp for 4b in parallel artificial permeability assay indicates the possibility of binding weakly to plasma proteins and high intestinal absorption fraction. Evaluation of the antidepressant‐ and anxiolytic‐like activities of 4b revealed both activities at the same dose of 1.25 mg/kg and seemed to be specific. The antidepressant and/or anxiolytic properties of 4b may be related to its first‐pass effect. 相似文献