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71.
72.
Halberg F Cornélissen G Stoynev A Ikonomov O Katinas G Sampson M Wang Z Wan C Singh RB Otsuka K Sothern RB Sothern SB Sothern MI Syutkina EV Masalov A Perfetto F Tarquini R Maggioni C Kumagai Y Siegelova J Fiser B Homolka P Dusek J Uezono K Watanabe Y Wu J Prikryl P Blank M Blank O Sonkowsky R Schwartzkopff O Hellbrügge T Spector NH Baciu I Hriscu M Bakken E 《Neuro endocrinology letters》2003,24(6):479-498
73.
Ostadal P Alan D Hajek P Horak D Vejvoda J Trefanec J Mates M Vojacek J 《Molecular and cellular biochemistry》2003,246(1-2):45-50
The aim of our study was to evaluate whether a single dose of cerivastatin at the time of admission of patients with unstable angina pectoris (UAP) or non-Q-wave myocardial infarction (NQMI) can influence the serum level of C-reactive protein (CRP), interleukin-6 (IL-6) and interleukin-8 (IL-8) 24 h later. Forty-four patients with rest chest pain and subendocardial ischemia on ECG were randomized to receive cerivastatin 0.3 mg at the time of admission (group C+) to standard therapy or to remain just on standard therapy (group C–). Blood samples for determination of troponin I (TI), CRP, IL-6 and IL-8 were collected at admission (entry level) and 24 h later (final level). Patients with non-physiological baseline levels of TI, as well as patients with progression to Q wave MI were excluded. All baseline, clinical and demographic data and final values of TI were comparable in the two groups. In patients treated with cerivastatin (group C+, n = 13) we observed decrease in the CRP level (–6.73 ± 3.93 mg/L); on the other hand, in group C– (n = 17) the CRP level increased (+7.92 ± 2.77 mg/L, p = 0.004). Similar differences were observed also in IL-6: in group C+ the level was significantly reduced as compared with the increase in group C– (–0.76 ± 0.52 vs. 4.58 ± 1.49 ng/L, p = 0.005). The level of IL-8 was not affected. Our results suggest that early treatment with cerivastatin can decrease the serum level of CRP and IL-6 in patients with UAP/NQMI; this might positively influence their prognosis. Nevertheless, further studies are needed to support this hypothesis. 相似文献
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75.
Phenology in central Europe – differences and trends of spring phenophases in urban and rural areas 总被引:5,自引:0,他引:5
Roetzer T Wittenzeller M Haeckel H Nekovar J 《International journal of biometeorology》2000,44(2):60-66
In order to examine the impacts of both large-scale and small-scale climate changes (urban climate effect) on the development
of plants, long-term observations of four spring phenophases from ten central European regions (Hamburg, Berlin, Cologne,
Frankfurt, Munich, Prague, Vienna, Zurich, Basle and Chur) were analysed. The objective of this study was to identify and
compare the differences in the starting dates of the pre-spring phenophases, the beginning of flowering of the snowdrop (Galanthus nivalis) and forsythia (Forsythia sp.), and of the full-spring phenophases, the beginning of flowering of the sweet cherry (Prunus avium) and apple (Malus domestica), in urban and rural areas. The results indicate that, despite regional differences, in nearly all cases the species studied
flower earlier in urbanised areas than in the corresponding rural areas. The forcing in urban areas was about 4 days for the
pre-spring phenophases and about 2 days for the full-spring phenophases. The analysis of trends for the period from 1951 to
1995 showed tendencies towards an earlier flowering in all regions, but only 22% were significant at the 5% level. The trends
for the period from 1980 to 1995 were much stronger for all regions and phases: the pre-spring phenophases on average became
earlier by 13.9 days/decade in the urban areas and 15.3 days/decade in the rural areas, while the full-spring phenophases
were 6.7 days earlier/decade in the urban areas and 9.1 days/decade earlier in the rural areas. Thus rural areas showed a
higher trend towards an earlier flowering than did urban areas for the period from 1980 to 1995. However, these trends, especially
for the pre-spring phenophases, turned out to be extremely variable.
Received: 21 October 1999 / Revised: 5 April 2000 / Accepted: 25 April 2000 相似文献
76.
Nicotine treatment increases intracellular free Ca(2+) concentration [Ca(2+)](i), stimulates catecholamine release, and elevates gene expression for the catecholamine biosynthetic enzymes tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH). However, the type of nicotinic acetylcholine receptors (nAChRs) mediating these events is unclear. The nAChR receptor antagonists alpha-bungarotoxin (alphaBTX) and methyllycaconitine greatly reduced the nicotine-triggered initial transient rise in [Ca(2+)](i) and prevented the second prolonged elevation of [Ca(2+)](i), suggesting the involvement of alpha7 nAChRs. Two specific alpha7 nicotinic agonists, 3-(2,4-dimethoxybenzilidene)anabaseine (DMXB) and E, E-3-(cinnamylidene)anabaseine (3-CA), were found to elicit a small, delayed increase in [Ca(2+)](i) with kinetics and magnitude similar to the second elevation observed with nicotine. This increase was inhibited by the inositol trisphosphate receptor antagonist xestospongin C. Exposure to 3-CA or DMXB for 6 or 24 h elevated TH and DBH mRNA levels two- to fourfold over control levels. These agonists were more effective than nicotine alone in increasing TH and DBH gene expression and significantly elevated [Ca(2+)](i) for up to 6 h. The increase in [Ca(2+)](i) or the elevation in TH mRNA by 3-CA was completely inhibited by alphaBTX. This study, for the first time, implicates stimulation of alpha7 nAChRs in the activation of TH and DBH gene expression. 相似文献
77.
Bronchial airway deposition and retention of particles in inhaled boluses: effect of anatomic dead space 总被引:1,自引:0,他引:1
Bennett William D.; Scheuch Gerhard; Zeman Kirby L.; Brown James S.; Kim Chong; Heyder Joachim; Stahlhofen Willi 《Journal of applied physiology》1998,85(2):685-694
The fractionaldeposition of particles in boluses delivered to shallow lung depths andtheir subsequent retention in the airways may depend on the relativevolume and size of an individual's airways. To evaluate the effect ofvariable anatomic dead space (ADS) on aerosol bolus delivery we hadhealthy subjects inhale radiolabeled, monodisperse aerosol(99mTc-iron oxide, 3.5 µm meanmondispersed aerosol diameter) boluses (40 ml) to a volumetric frontdepth of 70 ml into the lung at a lung volume of 70% total lungcapacity end inhalation. By using filter techniques, aerosolphotometry, and gamma camera analysis, we estimated the fraction of theinhaled boluses deposited in intrathoracic airways (IDF). ADS bysingle-breath N2 washout was alsomeasured from 70% total lung capacity. Results showed that among allsubjects IDF was variable (range = 0.04-0.43, coefficient ofvariation = 0.54) and increased with decreasing ADS(r = 0.76, P = 0.001, n = 16). We found significantlygreater deposition in the left (L) vs. right (R) lungs; mean L/R (ratioof deposition in L lung to R lung, normalized to ratio of L-to-R lungvolume) was 1.58 ± 0.42 (SD; P < 0.001 for comparison with 1.0). Retention of deposited particles at 2 hwas independent of ADS or IDF. There was significant retention ofparticles at 24 h postdeposition (0.27 ± 0.05) andslow clearance of these particles continued through 48 hpostdeposition. Finally, analysis of central-to-peripheral ratios ofinitial deposition and 24-h-retention gamma-camera images suggestsignificant retention of insoluble particles in large bronchial airwaysat 24 h postdeposition (i.e., 24 h central-to-peripheral ratio = 1.40 ± 0.44 and 1.82 ± 0.54 in the R and L lung, respectively; P < 0.02 for comparison with 1.0).These data may prove useful for 1)designing aerosol delivery techniques to target bronchial airways and2) understanding airway retention ofinhaled particles. 相似文献
78.
79.
Santosh B. Mhaske Bashar Ksebati Mark N. Prichard John C. Drach Jiri Zemlicka 《Bioorganic & medicinal chemistry》2009,17(11):3892-3899
Z- and E-Phosphonate analogues 12 and 13 derived from cyclopropavir and the corresponding cyclic phosphonates 14 and 15 were synthesized and their antiviral activity was investigated. The 2,2-bis(hydroxymethylmethylenecyclopropane acetate (17) was transformed to tetrahydropyranyl acetate 18. Deacetylation gave intermediate 19 which was converted to bromide 20. Alkylation with diisopropyl methylphosphonate afforded after protecting group exchange (21 to 22) acetylated phosphonate intermediate 22. Addition of bromine gave the dibromo derivative 16 which was used in the alkylation–elimination procedure with 2-amino-6-chloropurine to give Z- and E-isomers 23 and 24. Hydrolytic dechlorination coupled with removal of all protecting groups gave the guanine phosphonates 12 and 13. Cyclization afforded the cyclic phosphonates 14 and 15. Z-Phosphonate 12 was a potent and non-cytotoxic inhibitor of human and murine cytomegalovirus (HCMV and MCMV) with EC50 2.2–2.7 and 0.13 μM, respectively. It was also an effective agent against Epstein-Barr virus (EBV, EC50 3.1 μM). The cyclic phosphonate 14 inhibited HCMV (EC50 2.4–11.5 μM) and MCMV (EC50 0.4 μM) but it was ineffective against EBV. Both phosphonates 12 and 14 were as active against two HCMV Towne strains with mutations in UL97 as they were against wild-type HCMV thereby circumventing resistance due to such mutations. Z-Phosphonate 12 was a moderate inhibitor of replication of herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) but it was a potent agent against varicella zoster virus (VZV, EC50 2.9 μM). The cyclic phosphonate 14 lacked significant potency against these viruses. E-isomers 13 and 15 were devoid of antiviral activity. 相似文献
80.
Regulation of gene expression on the level of translation and mRNA turnover is widely conserved evolutionarily. We have found that the main mRNA decay enzyme, exoribonuclease Xrn1, accumulates at the plasma membrane-associated eisosomes after glucose exhaustion in a culture of the yeast S. cerevisiae. Eisosomal localization of Xrn1 is not achieved in cells lacking the main component of eisosomes, Pil1, or Sur7, the protein accumulating at the membrane compartment of Can1 (MCC) - the eisosome-organized plasma membrane microdomain. In contrast to the conditions of diauxic shift, when Xrn1 accumulates in processing bodies (P-bodies), or acute heat stress, in which these cytosolic accumulations of Xrn1 associate with eIF3a/Rpg1-containing stress granules, Xrn1 is not accompanied by other mRNA-decay machinery components when it accumulates at eisosomes in post-diauxic cells. It is important that Xrn1 is released from eisosomes after addition of fermentable substrate. We suggest that this spatial segregation of Xrn1 from the rest of the mRNA-decay machinery reflects a general regulatory mechanism, in which the key enzyme is kept separate from the rest of mRNA decay factors in resting cells but ready for immediate use when fermentable nutrients emerge and appropriate metabolism reprogramming is required. In particular, the localization of Xrn1 to the eisosome, together with previously published data, accents the relevance of this plasma membrane-associated compartment as a multipotent regulatory site. 相似文献