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991.
Paweł Zieliński Wojciech Dyszkiewicz Cezary T. Piwkowski Grzegorz Dworacki Lukasz Gasiorowski 《Cancer epidemiology》2009,33(5):387-390
Background: The aim of this study was to analyze the properties of the immune cell microenvironment of regional lymph nodes (LNs) positive for lung cancer. Methods: Twenty-four patients operated on for stages T1 and T2 of the NSCLC, were enrolled in the study. Peripheral blood and LN tissue were obtained from different lymph node sites and levels. As a control, LN tissue was taken from patients diagnosed with emphysema or pneumothorax. The cells from randomly chosen LN were tested by multi-color flow cytometry. Separate portions of LN were snap-frozen and examined for the presence of cytokeratin positive cells (CK). Propensity for apoptosis, level of TCR zeta chain expression of T cells and the number and maturation status of dendritic cells were confronted with the presence of CK-positive cells. Results: The presence of metastases correlated with the downregulation of TCR zeta, especially CD8(+) T cells. The most striking feature was the reduction in the number of myeloid CD11c(+) dendritic cells in the LN of patients with LN metastases. This could be a reflection of the immunodeficient state observed in lung cancer patients. Even in the absence of metastases in the regional LN, the same type of changes in the LN microenvironment were observed in those LN located nearer the primary tumor. Conclusions: The preliminary results of this study suggest that this approach may be helpful as an independent tumor staging factor. It is also worth noting that part of the staging process could also be based on features describing the immune cells in the peripheral blood. 相似文献
992.
In this study, two ursane-type triterpenes, i. e., ursolic acid (UA) and 3-O-β-acetoxyursolic acid (AUA), were isolated and quantified in Sorbus intermedia (EHRH.) PERS. fruits. UA and AUA levels differed slightly throughout fruit maturation, and both triterpenes showed similar dynamics of accumulation with the highest levels found in ripe fruits (up to 6.33±0.56 and 1.17±0.18 mg/g dw. of UA and AUA, respectively). The extracts derived from unripe fruits displayed significant cytotoxic effects against WM793, DU-145, PC3, 8505C, Caco2 and A549 cells, but no correlation between UA and AUA levels and cytotoxicity was found. On the other hand, extracts from mature fruits were not active towards almost all of the tested cell lines. The chemometric approach showed that the extracts derived from fruits harvested earlier clustered to form a clearly distanced group from extracts prepared from more-mature fruits. The extracts at higher concentrations formed separate groups, which indicated the concentration-dependent effect of these extracts on the cells. 相似文献
993.
Maria Żaak Paweł Migula Dominika Stygar Bogdan Doleżych Katarzyna Michalczyk 《Comptes rendus biologies》2012,335(10-11):645-656
Cameraria ohridella is an invasive leaf miner, a severe pest of horse chestnut trees. Chemical control needs recognition of intrinsic metabolic capability to cope with external stressing factors. Our tasks were to check annual effects of generation, and host tree age on detoxifying abilities of the last larval stage. Activities of CAT, SOD, GSTPX, GST CarE and AChE were assayed in the midgut of larvae from two localities during 3 years and three generations, annually. Activities of GSTPX and GST were high, but CAT and SOD were low in relation to other lepidopteran larvae. In general, the second generation larvae had the highest activity, indicating an effective defence against allelochemicals produced by the host. Effects of host tree age were significant for SOD, GSTPX and CarE activities. Significant annual differences on enzyme profiles of CAT, SOD, CarE and AChE reflected differences of temperature and precipitation between consecutive years. 相似文献
994.
995.
Krystyna A Mathiak Małgorzata Łuba Klaus Mathiak Katarzyna Karzel Tomasz Wolańczyk Elżbieta Szczepanik Paweł Ostaszewski 《BMC neurology》2010,10(1):69
Background
Measuring quality of life (QOL) helps to delineate mechanisms underlying the interaction of disease and psychosocial factors. In adults, epileptic foci in the left temporal lobe led to lower QOL and higher depression and anxiety as compared to the right-sided foci. No study addressed the development of QOL disturbances depending on the lateralization of epileptogenic focus. The objective of our study was to examine QOL in children with lateralized epileptiform discharges. 相似文献996.
997.
It is recommended that browse should be an important part of diets for browsing and intermediate feeding type ruminants. However, provision of browse in winter time is problematic for many zoos located in the temperate climate. Drying or freezing of branches are commonly practiced solutions to this problem, but ensiling of tree leaves could also be an attractive option. The aim of this study was to determine the effect of drying and ensiling of different tree leaves on preference of their intake by nyala antelope (Tragelaphus angasii), an intermediate feeding type ruminant. A study was conducted on five nyala fed a standard diet (meadow hay, dehydrated chopped lucerne and limited concentrates) before and during the study. Preference of intake of five feeds was tested: dried maple (A. platanoides), oak (Q. robur), willow (S. alba), and ensiled maple and lime (T. cordata) leaves. Each day two tested feeds were offered to each animal. After 4 h of presentation, feed refusals were weighed and preference ratio for each tested feed and animal was calculated. Then, preferences were ranked using a pairwise comparison chart. Dried maple and oak leaves were preferred more than other leaves whereas ensiled lime leaves were the least preferred. On the other hand, ensiled and dried maple leaves were equally preferred. Results of this study showed that palatability of ensiled tree leaves should not be a concern when feeding nyala, and likely also other browsing or intermediate feeding type ruminants, but palatability of silage may depend on the species of tree. 相似文献
998.
Lysine accepting transfer RNA of lupin seeds and lupin embryo axes can be fractionated into at least 5 species by reversed-phase chromatography (RPC-5). One main and two minor isoacceptors were observed in wheat and barley embryos. Changes in isoaccepting species of tRNA1ys were followed in cotyledons of germinating lupin seedlings. Ribosome binding studies revealed that one of the main lupin tRNA1ys species recognizes the AAG codon, the second AAA and the third one AAA and AAG. 相似文献
999.
Sławomir Wilczyński Barbara Pilawa Robert Koprowski Zygmunt Wróbel Marta Ptaszkiewicz Jan Swakoń Paweł Olko 《Radiation and environmental biophysics》2014,53(1):203-210
The aim of this work was to determine the concentrations and properties of free radicals in piperacillin, ampicillin, and crystalline penicillin after gamma irradiation. The radicals were studied by electron paramagnetic resonance (EPR) spectroscopy using an X-band spectrometer (9.3 GHz). Gamma irradiation was performed at a dose of 25 kGy. One- and two-exponential functions were fitted to the experimental data, in order to assess the influence of the antibiotics’ storage time on the measured EPR lines. After gamma irradiation, complex EPR lines were recorded confirming the presence of a large number of free radicals formed during the irradiation. For all tested antibiotics, concentrations of free radicals and parameters of EPR spectra changed with storage time. The results obtained demonstrate that concentration of free radicals and other spectroscopic parameters can be used to select the optimal parameters of radiation sterilization of β-lactam antibiotics. The most important parameters are the constants τ (τ 1(A),(I) and τ 2(A),(I)) and K (K 0(A),(I), K 1(A),(I), K 2(A),(I)) of the exponential functions that describe free radicals decay during samples storage. 相似文献
1000.
The impact of Stratiotes aloides L. (water soldier) on the accumulation and concentration of nitrogen and phosphorus, seston concentrations and provision a habitat for planktonic crustaceans was studied in a Polish oxbow lake during 2002–2004. The Stratiotes stand and the open water differed in the concentrations of mineral nitrogen and chlorophyll a. Stratiotes accumulated significantly more nitrogen in spring. The lower TN:TP ratio, concentrations of mineral nitrogen and chlorophyll a in stands of the water soldier may suggest nitrogen limitation in the littoral of the oxbow lake. The decrease of phytoplankton biomass in the Stratiotes stands may also result from shading and/or allelopathy. The plants did not reduce seston concentrations in the littoral but did affect the abundance and diversity of planktonic and bentho-planktonic crustaceans and probably provided a daytime refuge for Ceriodaphnia and older stages of Cyclopoida but not for Daphnia. 相似文献