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81.
It is commonly assumed that transformations of endosymbionts into organelles are exceptionally rare evolutionary events because of hypothetical difficulties in the origin of an import apparatus for nuclear-encoded, organelle-targeted proteins along with their targeting signals. A challenge to this view comes from recent studies of protein import into the cyanobacterial endosymbionts/organelles of Paulinella chromatophora. 相似文献
82.
Andrzej Wuczyński Bartosz Smyk Paweł Kołodziejczyk Wiesław Lenkiewicz Grzegorz Orłowski Andrzej Pola 《Central European Journal of Biology》2012,7(3):495-506
South-western Poland belongs to the key staging areas for geese in Europe, supporting some 100000 birds in recent years. We
compared goose counts conducted in the 1970s, 1990s and during 2009–2011 in this region, and linked the findings to the recent
assessments of trends in the flyway-populations. Numbers increased several dozen times between the first two counts and have
stabilized to the present. More than 14% of the flyway Tundra Bean Goose (Anser fabalis rossicus) stopped over in SW Poland on passage. Smaller numbers of White-fronted Goose (A. albifrons), Greylag Goose (A. anser), and four other rarer species, have all increased since the 1970s. The likely factors responsible for these changes are
mild weather conditions, increased availability of large water bodies and shifts in winter ranges of particular species. Temporal
mismatch between SW Poland and the total flyways in Bean and White-fronted Geese was recorded when we compared the long-term
and the short-term population trends. Increasing reports of other species in SW Poland match the general tendencies in Europe.
These data document that regional trends are not a simple reflection of those in flyways as a whole. To understand changes
in goose populations a re-established international count network is desired. 相似文献
83.
Ewa M. Skibniewska Michał Skibniewski Tadeusz Kosla 《Central European Journal of Biology》2012,7(5):817-824
The aim of the investigations was the determination of the Cu contents in the liver, kidneys and skeletal muscles of canine females. Material for research was collected post mortem from 45 animals aged 1 to 18 years coming from the Warsaw area. The effect of the health state, age and life conditions on the distribution of copper in the investigated organs was estimated. That element was determined using the method of inductively coupled plasma-atomic emission spectrometry (ICP-AES). In the liver, the average Cu contents amounted to 24.04 mg kg−1 wet weight, in kidneys to 2.90 mg kg−1 wet weight and in muscles to 0.94 mg kg−1 wet weight. The highest values of copper content in particular tissues and organs were noted in the group of animals with neoplastic changes. In respect to the animal age the highest mean values of the copper content were noted in the oldest animals. They amounted to 30.97 mg kg−1 in the liver, 3.34 mg kg−1 in kidneys and 1.18 mg kg−1 wet weight in muscles. Considering life conditions of the dogs it was observed that the higher mean values in all the investigated organs occurred in dogs coming from the urban areas. 相似文献
84.
Malgorzata Szczepańska Przemyslaw Wirstlein Jana Skrzypczak Pawe? P Jagodziński 《Reproductive biology and endocrinology : RB&E》2012,10(1):1
Background
A decrease in HOXA11 expression in eutopic mid-secretory endometrium has been found in women with endometriosis-associated infertility. 相似文献85.
Anna Mucha-Małecka Bogdan Gliński Marcin Hetnał Magdalena Jarosz Jacek Urbański Beata Frączek-Błachut Paweł Dymek Krzysztof Małecki Agnieszka Chrostowska 《Reports of Practical Oncology and Radiotherapy》2012,17(3):141-145
AimTo report the long-term follow-up of a cohort of adult patients with LGG post-operatively irradiated in one institution, and to identify prognostic factors for progression free survival.BackgroundThere is little consensus about the optimal treatment for low-grade glioma (LGG), and the clinical management of LGG is one of the most controversial areas in neurooncology. Radiation therapy is one option for treatment of patients with LGG, whereas other options include postoperative observation.Materials and methodsBetween 1975 and 2005, 180 patients with LGG (WHO II) received postoperative irradiation after non radical (subtotal or partial) excision. Patients had to be 18 years of age or older, and have histologic proof of supratentorial fibrillary (FA), protoplasmic (PA) or gemistocytic astrocytoma (GA). Radiotherapy was given within 3–10 weeks after surgery. Treatment fields were localized and included the preoperative tumor volume, with a 1–2 cm margin, treated to a total dose of 50–60 Gy in 25–30 fractions over 5–6 weeks.ResultsActuarial ten-year progression free survival (APFS) in the whole group was 19%. The worse prognosis was observed in patients with GA. Ten-year APFS rates for GA, PA and FA were 10%, 18% and 22%, respectively.ConclusionThe findings from our long-term cohort of 180 patients with LGG confirmed by uni- and multivariate analysis demonstrated that only astrocytoma histology significantly determined the prognosis. The best survival was observed in patients with the fibrillary variant, and the worst for the gemistocytic one. 相似文献
86.
Aleksandra Kładna Paweł Berczyński Irena Kruk Teresa Michalska Hassan Y. Aboul‐Enein 《Luminescence》2012,27(6):473-477
The direct effects of the four catecholamines (CATs), adrenaline (A), noradrenaline (NA), dopamine (D) and isoproterenol (I), on free radicals were investigated using the free radical 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH?) and hydroxyl radial (HO?). The CATs examined were found to inhibit the ESR signal intensity of DPPH? in a dose‐dependent manner over the range 0.1–2.5 mmol/L in the following order: NA > A > I > D, with IC50 = 0.30 ± 0.03 for noradrenaline and IC50 = 0.86 ± 0.02 for dopamine. Hydroxyl radicals were produced using a Fenton reaction in the presence of the spin trap 5,5‐dimethyl‐1‐pyrroline N‐oxide (DMPO), and ESR technique was applied to detect the CATs reactivity toward the radicals. The reaction rates constant (kr) of CATs with HO? were found to be in the order of 109 L/mol/s, and the kr value for noradrenaline was the highest (kr = 8.4 × 109 L/mol/s). The CATs examined exhibited also a strong decrease in the light emission (62–73% at 1 mmol/L concentration and 79–89% at 2 mmol/L concentration) from a Fenton‐like reaction. These reactions may be relevant to the biological action of these important polyphenolic compounds. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
87.
88.
Karakulska J Fijałkowski K Nawrotek P Pobucewicz A Poszumski F Czernomysy-Furowicz D 《Journal of microbiology (Seoul, Korea)》2012,50(3):444-451
The aim of this study was an analysis of the staphylococcal flora of the nasal cavity of 42 healthy horses from 4 farms, along with species identification of CoNS isolates and determination of resistance to 18 antimicrobial agents, particularly phenotypic and genotypic methicillin resistance. From the 81 swabs, 87 staphylococci were isolated. All isolates possessed the gap gene but the coa gene was not detected in any of these isolates. Using PCR-RFLP of the gap gene, 82.8% of CoNS were identified: S. equorum (14.9%), S. warneri (14.9%), S. sciuri (12.6%), S. vitulinus (12.6%), S. xylosus (11.5%), S. felis (5.7%), S. haemolyticus (3.4%), S. simulans (3.4%), S. capitis (1.1%), S. chromogenes (1.1%), and S. cohnii subsp. urealyticus (1.1%). To our knowledge, this was the first isolation of S. felis from a horse. The species identity of the remaining Staphylococcus spp. isolates (17.2%) could not be determined from the gap gene PCR-RFLP analysis and 16S rRNA gene sequencing data. Based on 16S-23S intergenic transcribed spacer PCR, 11 different ITS-PCR profiles were identified for the 87 analyzed isolates. Results of API Staph were consistent with molecular identification of 17 (19.5%) isolates. Resistance was detected to only 1 or 2 of the 18 antimicrobial agents tested in the 17.2% CoNS isolates, including 6.9% MRCoNS. The mecA gene was detected in each of the 5 (5.7%) phenotypically cefoxitin-resistant isolates and in 12 (13.8%) isolates susceptible to cefoxitin. In total, from 12 horses (28.6%), 17 (19.5%) MRCoNS were isolated. The highest percentage of MRCoNS was noted among S. sciuri isolates (100%). 相似文献
89.
90.
Jolanta Bratosiewicz-W?sik Joanna Smoleń-Dzirba Annemieke J. Rozemuller Casper Jansen Wim Spliet Gerard H. Jansen Tomasz J. W?sik Pawe? P. Liberski 《朊病毒》2012,6(4):413-416
Creutzfeldt-Jakob disease (CJD) is a rare transmissible neurodegenerative disorder. The etiology of sporadic form of CJD remains unsolved. In addition to the codon 129 polymorphism, polymorphisms in the non-coding region of PRNP are considered as important factors in sCJD development. To assess a possible association between PRNP 1368 SNP and sCJD, we compared the genotype, allele and haplotype frequencies of the 1368 SNP among 46 sCJD patients of Dutch origin with the respective frequencies in healthy controls. We detected a significant association between sCJD and 1368T/T genotype. A significant difference was also observed in 1368 alleles’ distribution. In the haplotype analysis, haplotype 1368C-129G was associated with decreased risk of sCJD in Dutch population. Our findings support the hypothesis that genetic variations in the regulatory region of the PRNP gene may influence the pathogenesis of sCJD. 相似文献