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991.
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993.
Herder S Votýpka J Jirků M Rádrová J Janzen CJ Lukes J 《Experimental parasitology》2007,117(1):111-114
Using green fluorescent protein as a reporter, we have shown that the strain 29-13 of Trypanosoma brucei, widely used for inducible down-regulation of mRNA, is inducible in, but not permissive for the tsetse flies Glossina palpalis gambiensis and Glossina morsitans morsitans. Within two weeks post-infection, 42% males and females of teneral and non-teneral tsetse flies harboured intestinal infections, yet not a single infection progressed into the salivary glands. 相似文献
994.
Pallová P Hercík K Sasková L Nováková L Branny P 《Biochemical and biophysical research communications》2007,355(2):526-530
Streptococcus pneumoniae carries a single Ser/Thr protein kinase gene stkP in its genome. Biochemical studies performed with recombinant StkP have revealed that this protein is a functional membrane-linked eukaryotic-type Ser/Thr protein kinase. Here, we demonstrate that the deletion of its extracellular domain negatively affects the stability of a core kinase domain. In contrast, the membrane anchored kinase domain and the full-length form of StkP were stable and capable of autophosphorylation. Furthermore, evidence is presented that StkP forms dimers through its transmembrane and extracellular domains. 相似文献
995.
Spikes arriving at the synaptic connection produce short-term plastic changes of the synaptic efficacy. Model experiments
have shown that paired-pulse facilitation attaining its maximum after a specific interval between a pair of arriving spikes
might turn a “weak” plastic synapse attached to an integrate-and-fire neuron to a frequency-tuned device. Resulting computational
capabilities create biologically plausible mechanisms of information processing relating to: (i) real-time identification
of temporal patterns in a stream of random spiking activity (a recognition problem); and (ii) codetermination of the specific
activity routing among neurons (an addressing problem) resulting in definite spatio-temporal patterns of the output activity
(an input-output pattern problem). 相似文献
996.
Potácová A Adamcová M Cajnáková H Hrbatová L Sterba M Popelová O Simůnek T Ponka P Gersl V 《Physiological research / Academia Scientiarum Bohemoslovaca》2007,56(2):251-254
The aim of this study was to analyze the ECG time intervals in the course of the development of chronic anthracycline cardiomyopathy in rabbits. Furthermore, this approach was employed to study the effects of a model cardioprotective drug (dexrazoxane) and two novel iron chelating compounds--salicylaldehyde isonicotinoyl hydrazone (SIH) and pyridoxal 2-chlorobenzoyl hydrazone (o-108). Repeated daunorubicin administration induced a significant and progressive prolongation of the QRS complex commencing with the eighth week of administration. At the end of the study, we identified a significant correlation between QRS duration and the contractility index dP/dt(max) (r = -0.81; P<0.001) as well as with the plasma concentrations of cardiac troponin T (r = 0.78; P<0.001). In contrast, no alterations in ECG time intervals were revealed in the groups co-treated with either dexrazoxane or both novel cardioprotective drugs (SIH, o-108). Hence, in this study, the QRS duration is for the first time shown as a parameter suitable for the non-invasive evaluation of the anthracycline cardiotoxicity and cardioprotective effects of both well established and investigated drugs. Moreover, our results strongly suggest that novel iron chelators (SIH and o-108) merit further study as promising cardioprotective drugs against anthracycline cardiotoxicity. 相似文献
997.
Bronský J Nedvídková J Zamrazilová H Pechová M Chada M Kotaska K Nevoral J Průsa R 《Physiological research / Academia Scientiarum Bohemoslovaca》2007,56(1):89-96
In this study, we describe changes of plasma levels of the hypothalamic neuropeptide orexin A in obese children during the reduction of body weight and its relationship to other biochemical and anthropometrical parameters. We measured orexin A fasting plasma levels by the RIA method in 58 obese children--33 girls and 25 boys; mean age 13.1+/-0.38 years (range 7-18.5) before and after 5 weeks of weight-reduction therapy. Leptin, IGF-1, and IGFBP-3 levels were measured in all the subjects and were compared to orexin A levels and anthropometrical data. Average weight in subjects before weight-reduction was 74.2+/-2.79 kg and after weight-loss 67.4+/-2.60 kg (p<0.0001). Orexin A levels before the therapy were 33.3+/-1.97 pg/ml and after the therapy 51.7+/-3.07 pg/ml (p<0.0001). Levels of orexin A were not significantly different between girls and boys (p=0.7842). We found negative correlation between orexin A and age (r = -0.5395; p<0.0001), body height (r = -0.4751; p=0.0002), body weight (r = -0.4030; p=0.0017) and BMI (r = -0.2607; p=0.0481). No correlation was found between orexin A and IGF-1, IGFBP-3 or leptin. Orexin A plasma levels increased during body weight loss, whereas the reverse was true for leptin levels. These findings support the hypothesis that orexin A may be involved in regulation of nutritional status in children. 相似文献
998.
Lauková Andrea Chrastinová Ľubica Micenková Lenka Bino Eva Kubašová Ivana Kandričáková Anna Gancarčíková Soňa Plachá Iveta Holodová Monika Grešáková Ľubomíra Formelová Zuzana Simonová Monika Pogány 《Probiotics and antimicrobial proteins》2022,14(5):845-853
Probiotics and Antimicrobial Proteins - Young rabbits are susceptible to gastrointestinal diseases caused by bacteria. Enterococcus hirae can be associated with diseases. But enterocins produced by... 相似文献
999.
Vladimír Kren Anna Fiserová Lenka Weignerová Ivan Stibor Petr Halada Vera Prikrylová Petr Sedmera Miloslav Pospísil 《Bioorganic & medicinal chemistry》2002,10(2):415-424
Dimers of agroclavine (1) and terguride (2), as well as a series of terguride oligomers, for example trimers (5, 6), tetramer (7), hexamer (8) and functionalized tergurides for further complex clustering were synthesized. Terguride oligomers were screened for their direct cellular toxicity on lymphoma cell lines in vitro and for their immunomodulating activities, represented by the natural killer (NK) cell-mediated cytotoxicity, as the most sensitive screening marker during immune responses. Dimers linked via aromatic spacer showed a high toxicity (1 microM) to lymphoma cells, which was not detected in other derivatives. In vitro and ex vivo experiments performed on mouse spleen lymphocytes in the presence of terguride oligomers demonstrated an immunosuppressive effect of dimers with aromatic spacer (4c-d) and NK cell stimulatory effect of terguride hexamer (8) and trimer with aliphatic spacer (5c). There is a considerable evidence that indolic part of molecule contributes to immunosuppressive action of terguride, which is potentiated in dimers carrying aromatic linker. This effect can be reversed by higher oligomerization of the respective alkaloids. 相似文献