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W artykule przedstawiono dwie metodyki badań faunistycznych dotyczących ptaków oraz mięczaków. Do badań bogactwa i różnorodności gatunkowej posłużono się przede wszystkim analizą statystyczną. W pracy omówiono metodykę badań terenowych pozwalającą na ocenę różnorodności gatunkowej. Zrealizowane badania dotyczyły dwóch grup: awifauny i malakofauny. Pierwsze zrealizowano w biotopie Uroczysko „Wielki Las” przylegającym do Jeziora Zgierzynieckiego (na którego obszarze utworzono „Rezerwat im. Bolesława Papiego”), zaś drugie na Poligonie wojskowym Biedrusko. Do ustalenia rozmieszczenia i liczebności ptaków na terenie rezerwatu posłużyła kombinowana metoda kartograficzna z modyfikacjami L. Tomiałojcia. W przypadku badań malakofauny przeprowadzono badania jakościowe oraz ilościowe. W ramach tych badań wykorzystano wiele wskaźników analitycznych oraz syntetycznych pomocnych przy ocenie bogactwa i różnorodności, które mogą być także wygodne przy waloryzacji przyrodniczej. Zdobyte doświadczenie jest przekazywane studentom w ramach przedmiotu „Ekologia”.
This study investigated the extend to which the snail Columella edentula is more strongly associated with the small balsam Impatiens parviflora than with other plants in the herb layer of an oak-hornbeam forest, and to interpret the character of the interaction Impatiens parviflora - Columella edentula. Numbers of C. edentula and rates of colonization were compared on various plant species under natural and laboratory conditions. Seasonal variation in snail abundance on I. parviflora was observed on permanent plots. The leaf injuries caused by C. edentula were localized in respect of the morphological and anatomical structure of leaves. The results show that I. parviflora is one of the plant species of the herb layer that are most abundantly colonized by this snail in oak-hornbeam forest. Snail finds a plant particularly suitable as a place for resting. The most favoured attachment site is on the underside of the leaf, along the midrib, which provides the highest and relatively stable humidity, as well as protection from direct sunlight and predators. I. parviflora is also a food for the snails, but they do not eat these fragments of leaves where calcium carbonate is accumulated.
Androgenetic alopecia is caused by the influence of sex hormones on hair follicles and by hereditary factors. Characteristic for that type of alopecia is shortening of the hair growth phase and elongation of the rest phase caused by disturbance of the process of transformation of testosterone into dihydrotestosterone. Treatment of that type of alopecia involves 5α-reductase inhibitors, antagonists of the androgenic receptor or stimulating proliferation of cells to induce the hair growth. A number of plant raw materials work that way, thus they can be used in treatment of this type of alopecia.
The pattern of dendritic branching along with the receptor and channel composition and density of synapses regulate the electrical properties of neurons. Abnormalities in dendritic tree development lead to serious dysfunction of neuronal circuits and, consequently, the whole nervous system. Not surprisingly, the complicated and multi-step process of dendritic arbor development is highly regulated and controlled at every stage by both extrinsic signals and intrinsic molecular mechanisms. In this review, we analyze the molecular mechanisms that contribute to cellular processes that are crucial for the proper formation and stability of dendritic arbors, in such distant organisms as insects (e.g. Drosophila melanogaster), amphibians (Xenopus laevis), and mammals.
Introduction: Mammalian target of rapamycin (mTOR) is a protein kinase that regulates cellular metabolism. Adequate mTOR activity is needed for development as well as proper physiology of mature neurons. Changes in mTOR activity are often observed in neuropathology. Several groups reported that seizures increase mTOR activity, and mTOR contributes to spontaneous seizures. However, the current knowledge about 1) the spatiotemporal and 2) the subcellular pattern of mTOR activation as well as 3) mTOR downstream effectorsin epilepsy is limited. Effects of mTOR insufficiency in seizures also remain under investigated. Aim: The aim of my team is to understand regulation and contribution of mTOR to epilepsy and pinpointing cellular mechanisms downstream mTOR. Methods: To study a role of mTOR in epilepsy we used models of pharmacological treatment with kainic acid (KA). We performed analysis of status epilepticus (SE) severity and progression. We analyzed with quantitative Western-blot and microarrays changes in signaling pathways and gene expression. Subcellular distribution of mTOR and its activity was analyzed by live microscopy. Results: We showed that SE induces mTOR first in neurons and next in astrocytes. At early times post seizures mTOR translocates to the nucleus, where its activity increases gradually. We showed that mTOR is involved in KA-dependent gene expression and genes regulated by mTOR regulate cytoskeleton. One of them, Elmo-1 regulates axonal growth and dendritic spine changes. Our research shows also that insufficient mTOR activity lead to increased sensitivity to KA. Conclusions: mTOR is an important player in epilepsy. One of the processes likely controlled by mTOR in epilepsy is transcription of genes responsible for cytoskeleton rearrangement. On the other hand, insufficient mTOR activity decreases threshold for epileptic-like neuronal activity. FINANCIAL SUPPORT: The research was supported by Polish National Science Centre (grants no. 2012/05/B/ NZ3/00429; 2012/07/E/NZ3/00503), 7FP grant (no. 602391, “EPISTOP”) and the Polish Ministerial funds for science (years 2014–2018) for the implementation of international co‑financed project. JJ is a recipient of the Foundation for Polish Science “Mistrz” Professorial Subsidy.
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