Wyniki wyszukiwania - Biblioteka Nauki

1

Nowe stanowiska widlaczka torfowego Lycopodiella inundata [L.] Holub na Garbie Gielniowskim [Wyzyna Malopolska]

100%

Podgorska M.

|

nr 3

97-105

2

Zagadnienia geobotaniczne Garbu Gielniowskiego. Część IV. Klasyfikacja roślin oparta na ekologicznych liczbach wskaźnikowych

100%

Podgorska M.

|

nr 1

3

Zagadnienia geobotaniczne Garbu Gielniowskiego. Część III. Grupy siedliskowe i syntaksonomiczne

100%

Podgorska M.

|

nr 2

4

The long-term changes of forest communities as an effect of former iron-ore mining activities and current forest management: importance for local biodiversity

100%

Podgorska M.

|

nr 1

EN

The human induced changes affect the transformation of different plant communities. In some cases this process can contribute to increase in local biodiversity, but it depends on type and manner of human activity involved. The main aim of this study is to answer the question how two anthropogenic factors (former and current) can modify the species composition in forest phytocoenoses. The study area is situated in the southern Poland (Małopolska Upland). The studies were carried out on two former (19th century) mining fields where planting Common Beech Fagus sylvatica (field A) and Scots Pine Pinus sylvestris (field B) have been done since the first half of the 20th century. On gob piles (sites transformed by former iron-ore mining), single-species beech (field A) or pine (field B) tree stands are undergoing secondary succession, and transform into multi-species, fertile deciduous forests. This secondary communities corresponding to the types of new, fertile soils (formed by clayey-loamy material of gob piles), generated as a result of mining activities. Whereas, on non-transformed areas forest communities with floristic structures and composition linked to poor and acidophilous phytocoenoses developed. These communities are also compatible with their respective, primary habitats (acid, poor, and sandy soils). Nonetheless, the secondary succession of forest communities on gob piles can be disturbed. In the herb layer of fertile habitats of post-mining sites where Pinus sylverstis was planted (field B) acidophilous species among mesophilous forest species were noted. This process of acidification of humus layer is induced by the fall of needles of pines and it has not been observed in communities with planted Fagus sylvatica (field A). It was found that previous mining activities now affect the secondary succession in the forest communities of northern part of the Małopolska Upland because they have created new habitats where process of forming mesophilous phytocoenoses was observed. Accordingly, former human activity leads to the increase in local biodiversity. On the other side current forest management can reduce this effect as a result of planting tree species which acidify these fertile habitats and suppressed the occurrence of mesophilous forest species, what, by contrast, decrease the species richness.

5

Nowe stanowiska Diphasiastrum tristachyum i D. zeilleri [Lycopodiaceae] na Wyzynie Malopolskiej

100%

Podgorska M.

|

nr 1

185-190

6

Wartość pokarmowa mieszanek jęczmienia, owsa i pszenżyta w zależności od ilości wysiewu

63%

Sobkowicz P. , Podgorska M.

|

2006

|

tom 142

7

Ekspansja Chamaenerion palustre (Onagraceae) na Wyżynie Małopolskiej

63%

Broz E. , Podgorska M.

|

tom 15

|

nr 1

21-42

8

Symphyotrichum ciliatum [Brachyactis ciliata] [Asteraceae] w Polsce

63%

Broz E. , Podgorska M.

|

nr 2

291-299

9

The extinction of stations of Pulsatilla patens (L.) Mill. subsp. patens (American pasqueflower) on the Malopolska upland

63%

Podgorska M. , Broz E.

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nr Suppl.1

10

The extinction of relict locations of Pleurospermum austriacum [L.] Hoffm. on the Malopolska Upland

51%

Broz E. , Podgorska M. , Przemyski A.

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tom 62

43-52

11

Recent advances in studies on biochemical and structural properties of equilibrative and concentrative nucleoside transporters

51%

Podgorska M. , Kocbuch K. , Pawelczyk T.

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nr 4

EN

Nucleoside transporters (NT) facilitate the movement of nucleosides and nucleobases across cell membranes. NT-mediated transport is vital for the synthesis of nucleic acids in cells that lack de novo purine synthesis. Some nucleosides display biological activity and act as signalling molecules. For example, adenosine exerts a potent action on many physiological processes including vasodilatation, hormone and neurotransmitter release, platelet aggregation, and lipolysis. Therefore, carrier-mediated transport of this nucleoside plays an important role in modulating cell function, because the efficiency of the transport processes determines adenosine availability to its receptors or to metabolizing enzymes. Nucleoside transporters are also key elements in anticancer and antiviral therapy with the use of nucleoside analogues. Mammalian cells possess two major nucleoside transporter families: equilibrative (ENT) and concentrative (CNT) Na+-dependent ones. This review characterizes gene loci, substrate specificity, tissue distribution, membrane topology and structure of ENT and CNT proteins. Regulation of nucleoside transporters by various factors is also presented.