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41.
During reproductive quiescence, apart from a rapid decrease in total protein content, there was a 2–3 fold decrease in the activity of certain enzymes (glutamic-oxaloacetic transaminase (GOT), alkaline phosphatase, acrosin inhibitors) in the seminal plasma of red deer stags. The activity of the enzymes of the spermatozoa, hyaluronidase and acrosin, increased in the seminal plasma, probably due either to ageing of the spermatozoa, accumulated in the epididymis, or to changes in the permeability of cell membranes.These phenomena were accompanied by an increased concentration of albumins originating in blood, and by a noticeable disappearance of globulin fractions. This would point to a change in the permeability of the tissue barriers in the deer stag reproductive system, and to a decreased rate of protein synthesis in particular sections of this system, especially in the epididymis, during reproductive quiescence. 相似文献
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Mikołaj Świerczyński Agata Szymaszkiewicz Jakub Fichna Marta Zielińska 《生物化学与生物物理学报:癌评论》2021,1875(1):188460
Colorectal cancer (CRC) is one of the most common cause of death among neoplasms around the world. The environmental factors, like diet and obesity, are crucial in CRC pathogenesis by creating cancer-favorable microenvironment and hormonal changes. Adiponectin, the adipose tissue-specific hormone, is generally considered to negatively correlate with CRC development. The interleukin 6 (IL-6) is one of the most important pro-inflammatory cytokine connected with CRC, which is strongly inflammation-associated. The opioids are variable group substantially correlated with cancers - the endogenous opioids affect immune system and cell cycle including proliferation and cell death whereas exogenous opioids are leading clinically used analgesics in terminal cancer patients. In this review we discuss the involvement of adiponectin, IL-6 and opioids in CRC pathogenesis, their link with obesity, possible cross-talk and potential novel therapeutic approach in CRC treatment. 相似文献
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A. Śliwińska O. Olszowska M. Furmanowa A. Nosov 《In vitro cellular & developmental biology. Plant》2008,44(2):69-77
Efficient plant regeneration through somatic embryogenesis was achieved in Polyscias filicifolia. Embryogenic calluses were induced on Murashige and Skoog (MS) basal medium supplemented with 0.5 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.0 mg l−1 benzylaminopurine (BAP; type I callus) and on MS medium with 2.0 mg l−1 2,4-D and 0.01 mg l−1 kinetin (type II callus) from leaf explants of a 2-yr-old plant. Primary somatic embryos (PSEs) developed after four passages
of suspension culture established from embryogenic callus when cultured in liquid half-strength MS medium (1/2 MS) without
growth regulators. PSEs in the cotyledonary stage were multiplied by adventitious embryogenesis. Single secondary somatic
embryos (SSEs) or their clusters developed at the base of PSE hypocotyls and regenerated into plantlets in a one-step process
on plant growth regulator-free 1/2 MS medium. Low sucrose concentration of 15 g l−1 promoted development of normal SSEs. All SSEs regenerated into single, well-rooted plantlets on a Nitsch and Nitsch medium
supplemented with 0.5 mg l−1 kinetin, 0.1 mg l−1 indole-3-butyric acid, and 10 mg l−1 adenine sulfate. Subsequent two subculture cycles on the same medium were necessary to obtain plantlets sufficiency developed
to allow successful transfer to the soil. Rooted plantlets were established in a peat mixture with 90% survival, with the
plants showing normal morphological characteristics. 相似文献
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Monika Marcinkowska Magdalena Kotańska Agnieszka Zagórska Joanna Śniecikowska Monika Kubacka Agata Siwek 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):536-545
Despite the substantial clinical success of aspirin and clopidogrel in secondary prevention of ischemic stroke, up to 40% of patients remain resistant to the available antiplatelet treatment. Therefore, there is an urgent clinical need to develop novel antiplatelet agents with a novel mechanism of action. Recent studies revealed that potent alpha 2B-adrenergic receptor (alpha 2B-ARs) antagonists could constitute alternative antiplatelet therapy. We have synthesized a series of N-arylpiperazine derivatives of 4,4-dimethylisoquinoline-1,3(2H,4H)-dione as potential alpha 2B receptor antagonists. The most potent compound 3, effectively inhibited the platelet-aggregation induced both by collagen and ADP/adrenaline with IC50 of 26.9?μM and 20.5?μM respectively. Our study confirmed that the alpha 2B-AR antagonists remain an interesting target for the development of novel antiplatelet agents with an alternative mechanism of action. 相似文献
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Flowers of Calendula officinalis were incubated with mevalonic acid doubly labelled with 14C in position 2 and 3H in positions 2R, 2S, 4R or 5R,S and the [3H/14C] ratios determined in squalene and pentacylic mono- and dihydroxy-triterpene alcohols and also in some derivatives prepared from the triterpene alcohols. 3H atoms were located in positions 3, 12, 16, 21, 29, 30 of the ursane skeleton, positions 3, 12, 29, 30 of the lupane skeleton and positions 3, 11, 12, 18 of the oleanane skeleton. Stabilization of α- and β-Amyrins, ω-taraxasterol and lupeol occurs with the elimination of a proton from positions 12, 21 and 29 (or 30) respectively. In addition, during hydroxylation of triterpene monols to the corresponding diols a proton is substituted by the hydroxyl group. 相似文献
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Description of the immature stages of two Mononychus species (Coleoptera: Curculionidae: Ceutorhynchinae) and a study of the host preferences of M. punctumalbum for Iris species in central Europe
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Jiří Skuhrovec Levent Gültekin Magdalena Śmigala Krystyna Winiarczyk Agnieszka Dąbrowska Rafał Gosik 《Acta zoologica》2018,99(3):296-318
Last larval instars and pupae of Mononychus punctumalbum (Herbst, 1784) and Mononychus schoenherri Kolenati, 1859 (Curculionidae, Ceutorhynchinae) are described in detail for the first time. No immatures of other species of this genus had previously been described. The immatures of Mononychus were compared with available data on immatures of all genera in the subfamily Ceutorhynchinae. Both the larvae and pupae of the two Mononychus species are very distinctive, having distinct characters from other genera in the subfamily Ceutorhynchinae. New bionomic data for M. punctumalbum concerning its host preferences for Iris species in central Europe can be used to verify literature data indicating the important role of the iris weevil in the dramatic decline in the plant's abundance in natural habitats as well as in gardens and other anthropogenic associations. 相似文献
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