Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 165

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
The mutual modulatory influence of the connective tissue stroma and tumour parenchyma, with ECM (extracellular matrix) and conecsine gaps has been described. The presence of cellular infiltration in stroma of cancers was also presented. The cellular infiltrations are symptoms of the tissular defence mechanism and/or secondary response on regressive changes such as necrosis and degeneration. They may also be a reaction to the presence of carcinogens. Taking under consideration stroma behaviour, tumours were divided into two groups: tumours producing stroma, i.e. sarcoma and tumours using local tissue, i.e. cancers. Anaplastic (low differentiated) tumours are accompanied by fibroplasia rejuvenation of connective tissue, while in highly differentiated tumours stroma is more like mature connective tissue. This determines the tumour cells’ penetration into stroma, as the more compact the stroma is, the higher propensity to microfocal and dispersed infiltration one may observe. The structure slackening fosters solid multifocal infiltration.
At the basis of neoplastic processes there lie molecular lesions i.e. non-lethal, multi-stage damage to genetic material. The paper describes damage to nuclear chromatin and the role of RNA in neoplasia as well as the involvement of adhesion molecules, extracellular matrix (ECM), signal transduction (including humoral signals) and the role of cell cycle in the process. The significance of molecular techniques in the diagnosis of tumours was also shown.
The paper presents a chronological outline of epochs covering about 5,000 years of human history, focusing on selected important developments in pathological anatomy and the figures with whom they were associated. It is not a complete list of authors and facts, in either human or veterinary medicine, owing to the limited size of the paper and the author’s subjective judgments.. The paper also presents a vision of pathological anatomy in the future, in the form of the so-called virtual section, based on digital photography and computer tomography.
There is a specific antagonism between an aging organism and neoplasia, in which the tumor is considered to influence the local tissue. It returns to some atavistic features, including the thermodynamic approach (2nd law of thermodynamics, Fig. 1), causing the rejuvenation of the surrounding tissue. The existence of various theories of oncogenesis entitles their supplementation with the theory of inflammaging: an entropic inflammation that can potentially have an indirect influence on the oncogenesis. This theory covers the effects of various causes of aging, including genetically programmed changes, telomere dependent processes and damage of genome, epigenome and proteome particles. The paper describes the patomechanism of inflammaging, including the role of mitochondria (point mutations and deletions especially in mtDNA), oxidative stress with overproduction and accumulation of free radicals and NFkB factor (nuclear factor kappa-light chain-enhancer of activated B cells) and the possibility of the influence of inflammaging on oncogenesis (Fig. 2). The inflamma-ging is programmed by hypothalamus using the immune-neuro-endocrine system, including gonadotropin releasing hormone (GnRH) that inhibits the NFkB factor with the inactivation of kinase IKK-beta. Regardless of that, the chronic inflammation, exceeding its defensive competence, lasts for years and can also be the beginning of neoplastic cells proliferation.
On the basis of the 2nd law of thermodynamics, the study presents a probable process in which a neoplastic cell passes into the dissipative state on its thermodynamic branch and self-transforms into a neoplastic cell. The self-transformation is promoted by a long-term unstable, highly unbalanced state in which cells that are sensitive to cancerogenesis obtain their own thermodynamic branch, and their self-organization is probably based on a disturbed relationship between entropy and temperature. Self-organization is related to the progressive imbalance. It promotes mistakes during genetic copies formation , spontaneous mutations and, as a result, cancerogenesis. A deterministic chaos is a creative process because it is the only one capable of generating completely new structures, such as neoplasms. Neoplastic cells succeed only when their environment (extracellular matrix – ECM) is damaged due to e.g. senile inflammation or inflammation caused by the neoplasm itself. This is known as the oncogenesis adaptation theory and it explains the evolution of neoplastic cells. The mutation leading to the neoplastic transformation of a cell is sometimes unfavorable or even harmful to the cell by preventing its proper adaptation to surrounding tissues. This can be useful in adaptive therapy of some neoplasms.
The histopathological examination can be supplemented by immunohisto(cyto)chemical examination, cytometry or molecular techniques, making it possible to determine the statistical probability of metastasis. This assists in the selection of appropriate individual treatment that can be the most effective and have the fewest side effects in a given patient. The study describes the basics of neoplastic treatment, including multidrug resistance (MDR). It characterizes the role of transporters (molecular pumps, e.g. ABC – ATP-binding cassettes, RND, SMR, MFS and P450 – CYP), complications of neoplastic therapy (e.g. myelosuppression, acute tumor lysis syndrome), and minimal residual disease (MRD).
The paper presents a historical outline of studies on tumours from prehistoric times (paleo-oncology) to the present, as well as explains how neoplastic processes developed and why they developed only in multicellular organisms (Metazoa). One of such explanations refers to the development of the body’s defence system in the form of a cellular (inflammatory) infiltrate directed both against exopathogens, e.g. viruses, and against neoplastic cells. The paper also discusses the role of the infiltrate in the primary and secondary neoplastic progression and in regression, as well as the influence of exogenous and endogenous factors, including dissipative factors, on tumour development.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.