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991.
Toto bodies are eosinophilic structures that resemble the cells of the superficial cell layer of the oral epithelium. Toto bodies commonly are associated with inflammatory gingival and other mucosal lesions including pyogenic granuloma, irritational fibroma, epulis fissuratum, peripheral giant cell granuloma and inflammatory hyperplastic gingivitis. We evaluated staining characteristics of Toto bodies to establish their origin and to identify their significance in lesions. We investigated pyogenic granuloma, fibroma and leukoplakia with epithelium that exhibited Toto bodies after hematoxylin and eosin (staining. Sections were stained with Alcian blue, periodic acid-Schiff and Ayoub-Shklar stains to evaluate staining intensity and distribution. More Toto bodies were found in pyogenic granuloma than in fibroma and leukoplakia. PAS and Alcian blue staining exhibited mild intensity and did not establish the origin of Toto bodies. High staining intensity and diffuse distribution of stain was observed using Ayoub-Shklar staining, which indicated that Toto bodies originate from keratin.  相似文献   
992.

Old collections from the Ordovician of the Barrandian area (Czech Republic) have yielded a probable vertical burrow that contains several dozen specimens of the pliomerid trilobite Placo‐paria (Placoparia) cambriensis Hicks, some of them enrolled. The fill of the burrow (classified as ?Skolithos isp.) also contains minute ovoid pellets corresponding to the ichnotaxon Tomaculum cf. problematicum Groom. The enrollment of a portion of the trilobite exoskeletons might reflect a defensive response. The pellets may be interpreted as fecal material or, less probably, as eggs. The exoskeletons and the pellets might have been mechanically trapped into the open burrow, or their concentration may have resulted from biological relationships between the tracemaker and the trilobites.  相似文献   
993.
Adjuvant arthritis (AA) is a condition that involves systemic oxidative stress. Unexpectedly, it was found that sarcoplasmic reticulum Ca2 +-ATPase (SERCA) activity was elevated in muscles of rats with AA compared to controls, suggesting possible conformational changes in the enzyme. There was no alteration in the nucleotide binding site but rather in the transmembrane domain according to the tryptophan polar/non-polar fluorescence ratio. Higher relative expression of SERCA, higher content of nitrotyrosine but no increase in phospholipid oxidation in AA SR was found. In vitro treatments of SR with HOCl showed that in AA animals SERCA activity was more susceptible to oxidative stress, but SR phospholipids were more resistant and SERCA could also be activated by phosphatidic acid. It was concluded that increased SERCA activity in AA was due to increased levels of SERCA protein and structural changes to the protein, probably induced by direct and specific oxidation involving reactive nitrogen species.  相似文献   
994.
Dopamine oxidation products such as H2O2 and reactive quinones have been held responsible for various toxic actions of dopamine, which have implications in the aetiopathogenesis of Parkinson's disease. This study has shown that N-acetylcysteine (0.25–1 mm) is a potent scavenger of both H2O2 and toxic quinones derived from dopamine and it further prevents dopamine mediated inhibition of Na+,K+-ATPase activity and mitochondrial respiratory chain function. The quinone scavenging ability of N-acetylcysteine is presumably related to its protective effect against dopamine mediated inhibition of mitochondrial respiratory chain activity. However, both H2O2 scavenging and quinone scavenging properties of N-acetylcysteine probably account for its protective effect against Na+,K+-ATPase inhibition induced by dopamine. The results have important implications in the neuroprotective therapy of sporadic Parkinson's disease since inactivation of mitochondrial respiratory activity and Na+,K+-ATPase may trigger intracellular damage pathways leading to the death of nigral dopaminergic neurons.  相似文献   
995.
Fifteen new thieno[2,3-b]- and thieno[3,4-b]pyrrolizines were synthesized and tested against two protein kinases, CDK1/cyclin B and GSK-3. Among these compounds, 3-(3-hydroxy-4-methoxyphenyl)-8H-thieno[2,3-b]pyrrolizin-8-one 4g was identified as a moderate inhibitor of these kinases. Its molecular modeling study brought to the fore the pivotal role of the 2-methoxyphenol grouping and the interest in replacing it by bioisosteric moieties in future pharmacomodulations.  相似文献   
996.

Over the period 2002–2019, air temperature and precipitation significantly increased regionally for Bratislava, which could lead to phenological changes in some plant species. This study aimed to analyse the changes in the intensity, timing, and duration of pollen seasons of three allergological important plant taxa (Alnus, Poaceae, Artemisia) in the study area over 18 years. The pollen sampling was performed using a Hirst-type sampler. Mann–Kendall tau test was used to determine trends in pollen season characteristics, while Spearman’s correlation analysis was used to identify the relationships between the characteristics of pollen seasons and both air temperature and precipitation trends. The notable changes in the pollen-season-related features were observed for all analysed taxa. The Alnus pollen season now reaches the peak earlier and its intensity is rising in line with the summer-autumn temperature increasing trend, while unexpectedly intensity and duration of the Artemisia pollen season are declining in line with the increased precipitation and/or temperature trends. On the other hand, the intensity of the Poaceae pollen season is also declining, however, without statistically significant correlations with recorded increases in meteorological parameters considered. This phenomenon is probably related to both the reduction of the area of grasslands due to urbanization and the implementation of effective maintenance of urban green areas (e.g., timely mowing preventing the repeatedly flowering of grasses).

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997.

Clusterin (CLU; also known as apolipoprotein J, ApoJ) is a protein of inconstant structure known to be involved in diverse processes inside and outside of brain cells. CLU can act as a protein chaperon or protein solubilizer, lipid transporter as well as redox sensor and be anti- or proapoptotic, depending on context. Primary structure of CLU is encoded by CLU gene which contains single nucleotide polymorphisms (SNP’s) associated with the risk of late-onset Alzheimer’s disease (LOAD). Studying a sample of Czech population and using the case-control association approach we identified C allele of the SNP rs11136000 as conferring a reduced risk of LOAD, more so in females than in males. Additionally, data from two smaller subsets of the population sample suggested a possible association of rs11136000 with diabetes mellitus. In a parallel study, we found no association between rs11136000 and mild cognitive impairment (MCI). Our findings on rs11136000 and LOAD contradict those of some previous studies done elsewhere. We discuss the multiple roles of CLU in a broad range of molecular mechanisms that may contribute to the variability of genetic studies of CLU in various ethnic groups. The above discordance notwithstanding, our conclusions support the association of rs1113600 with the risk of LOAD.

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998.
999.
Phytochemistry Reviews - The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China and its spread worldwide has become one of the biggest health problem due to the lack...  相似文献   
1000.
Plant Ecology - Plant mating systems may reflect an adaptation to a habitat type, with self-pollination being potentially common in unstable and disturbed conditions. We investigated the...  相似文献   
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