Search results

Sort By:

Limit search:

Horyzontalna transmisja komórek nowotworowych

100%

Baranowska M., Fol M.

Kosmos

2017

vol. 66

issue 2

297-311

Istnieją trzy udokumentowane przypadki zakaźnych nowotworów występujących w środowisku naturalnym: rak pyska diabła tasmańskiego, zakaźny psi guz weneryczny oraz białaczko-podobny nowotwór u małgwi piaskołazu. Komórki zakaźnego nowotworu charakteryzują się podobnym lub takim samym materiałem genetycznym, który jest odmienny od genomu gospodarza. Każdy z opisanych rodzajów nowotworów pochodzi od pierwotnego, wspólnego przodka i szerzy się horyzontalnie miedzy osobnikami. Nowotwór rozprzestrzenia się przez bezpośredni kontakt fizyczny (u psów i diabłów tasmańskich) lub poprzez czynniki środowiskowe, jak np. woda (małże). Mechanizmy, które doprowadziły do wyewoluowania zakaźnej postaci nowotworu i pozwalają nowotworowi unikać odpowiedzi odpornościowej gospodarza, nie są do końca poznane. W tym kontekście, pewne znaczenie może odgrywać poziom zróżnicowania genetycznego populacji zwierząt oraz brak/zaburzenia rozpoznawania swój-obcy. Bardziej dogłębne poznanie biologii tego typu nowotworów, ich dróg rozprzestrzeniania się, tworzenia przerzutów, sposobów unikania mechanizmów odpornościowych gospodarza, może udzielić wielu odpowiedzi na temat biologii innych nowotworów.

There are three documented cases of contagious cancers occurring in natural environment - devil facial tumor disease, canine transmissible venereal tumor and leukemia-like clam cancer. The tumor cells collected from different locations have identical chromosomal rearrangements and they are genetically distinct from their hosts. All the types of transmissible cancers come from an original, common ancestor and they spread through horizontal transmission between individuals. The neoplastic cells are transported through physical contact (dogs and Tasmanian devils) or by environmental factors, e.g. water (soft-shell clams). The mechanisms that led to appearance of the transmissible cancers and that allow the cancer to avoid the host immune response are not yet fully known. In this context, the genetic diversity of animal populations and the lack or disorder of the self/nonself-immune recognition may play a role. In-depth knowledge of biology of this type of cancer: how they can spread, cause metastasis, and avoid immune response, may help to elucidate biology of other cancers.

The State of Development of Equestrian Tourism in the Lublin Region in the Context of Environmental Conditions

100%

Brzezińska-Wójcik T., Baranowska M.

Polish Journal of Sport and Tourism

2012

vol. 19

issue 4

256-262

Introduction. In recent years spending free time in the Lublin Region has been more frequently related to equestrian tourism based on the infrastructure of the existing centres. Papers published so far focus mainly on a detailed description of features of horses used for equestrian tourism. Few papers have analysed offers and issues related to the promotion of this form of tourism. There is no paper discussing the spatial distribution of equestrian tourism centres, or analysing their offer at the regional scale. In response to this, a study was undertaken with special consideration of the features of the natural environment. Material and methods. In the period from October 2010 to April 2011, secondary information (statistics, registers, scientific papers) was analysed and primary material (field inventory, diagnostic interviews and an opinion poll) on the state of equestrian tourism in the Lublin Region was collected. Results. The analysis of the spatial distribution of 61 equestrian tourism centres subject to the inventory reveals that the highest number of centres function in the Zamooeæ and Biała Podlaska poviats. The comparison of offers in the scope of equestrian tourism in the Lublin Region shows that the basic offer of the region includes four kinds of services: horse riding, sleigh riding, chaise riding and horse riding courses. The highest number of horse treks is offered by centres in the Biała Podlaska poviat. Conclusions. In view of the data obtained, an asset in the scope of the development of equestrian tourism is the structure of offers directed at tourists and the infrastructure that already exists. Moreover, the development of this form of tourism is favoured by the features of the natural environment; the majority of trails and centres are located in environmentally valuable areas. Particularly the landscape, the filtrating-detoxicating properties of plant assemblages, their bioclimate and aesthetic value should contribute to the development of a complex offer (appropriate promotional package) of equestrian tourism in the Lublin Region

Refine search results

1 Kosmos

1 Polish Journal of Sport and Tourism

1 2017

1 2012

2 Baranowska M.

1 Brzezińska-Wójcik T.

1 Fol M.

Search results

Horyzontalna transmisja komórek nowotworowych

The State of Development of Equestrian Tourism in the Lublin Region in the Context of Environmental Conditions