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Max Kasparek 《Journal of Ornithology》1996,137(3):357-358
Ceryle rudis syriaca Roselaar, 1995 was separated from nominaterudis only by its longer wings. As variations in the wing length ofCeryle rudis follow Bergmann's rule, it is suggested thatsyriaca is not recognised as a separate named taxon.
Zusammenfassung Die Trennung vonCeryle rudis syriaca Roselaar, 1996 als eigene Subspezies basiert ausschließlich auf der etwas größeren Flügellänge. Da gezeigt werden konnte, daß die Flügellänge des Graufischers derBergmannschen Regel folgt, wird vorgeschlagen,syriaca wieder zu eliminieren.相似文献
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Max R. Taylor Lucy A. Lawson Virginia G. Lockard William R. Lockwood 《Mycopathologia》1984,88(2-3):173-180
Electron microscopic examination of yeasts of Blastomyces dermatitidis, exposed in vitro to concentrations of lidocaine that occur when the drug is used for topical anesthesia, showed that lidocaine rapidly damaged intracellular structures. The extent of damage was dependent on the concentration of drug and length of exposure. The observed ultrastructural changes were very similar to those reported for other drugs that directly damage membranes. This relationship suggests that the antifungal effect of lidocaine is the result of direct membrane damage. 相似文献
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In this article, we demonstrate that an increase in intracellular Ca2+ concentration may represent a specific common step(s) in the mechanism(s) of action of glutamate (Glu) and depolarizing agents on formation of inositol phosphates (IPs) in 8-day-old rat forebrain synaptoneurosomes. In fact, A23187, a Ca2+ ionophore, induces a dose-dependent accumulation of IPs, which is not additive with that evoked by Glu and K+ but is slightly synergistic with that induced by carbachol. In addition, Glu and K+ augment the intracellular Ca2+ concentration in synaptoneurosome preparations as measured by the fura-2 assay. The absence of external Ca2+ decreases basal and Glu-, and K(+)-stimulated formation of IPs. Cd2+ (100 microM) fully inhibits both Glu- and K(+)-evoked formation of IPs without affecting the carbachol-elicited response of IPs. Zn2+ inhibits Glu- and K(+)-stimulated accumulation of IPs (IC50 approximately 0.4 mM) but with a lower affinity than Cd2+ (IC50 approximately 0.035 mM). The organic Ca2+ channel blockers verapamil (10 microM), nifedipine (10 microM), omega-conotoxin (2 microM), and amiloride (10 microM) as well as the inorganic blockers Co2+ (100 microM) and La3+ (100 microM) block neither Glu- nor K(+)-evoked formation of IPs, a result suggesting that the opening of the L-, T-, N-, or P-type Ca2+ channels does not participate in these responses. All these data suggest that an increase in intracellular Ca2+ concentration resulting from an influx of Ca2+, sensitive to Cd2+ but not to other classical Ca2+ antagonists, may play a key role in the transduction mechanism activated by Glu or depolarizing agents. 相似文献
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Karen A. Keith Mary C. Duncan Max Murray Ken Bairden Andrew Tait 《International journal for parasitology》1990,20(8):1037-1045
In this study we have shown that NHS-biotin and I125-streptavidin can detect cuticular polypeptides of Ostertagia spp. The labelled polypeptide profile of intact nematodes is simple compared to the profile obtained by labelling homogenates. None of the major internal polypeptides are labelled and the subset of proteins labelled in intact nematodes appears to be mainly surface associated. The results presented here demonstrate that NHS-biotin may be used as a reagent for the analysis of surface polypeptides. The surface polypeptide profiles of the five major developmental stages (L1, L2, L3, L4 and adult) of Ostertagia circumcincta show a series of stage-specific molecules with no polypeptides common to all stages, indicating that the cuticle is a dynamic structure which changes throughout the life cycle. Similarity comparison of Ostertagia ostertagi L3 and L4 stage surface profiles showed that each stage is clearly distinct; comparison of these stages between the two species shows an overall similarity. 相似文献
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The effects of pentobarbitone on the transport of 45Ca2+ by rat brain mitochondria were studied, using the Ruthenium Red-EGTA quench technique. In the presence of succinate and inorganic phosphate, mitochondria rapidly accumulate 45Ca2+. Pentobarbitone (0.1-1.0 mM) stimulates the initial rate of Ca2+ transport. In contrast, pentobarbitone (1 mM) did not affect the NaCl (50 mM)-induced efflux of 45Ca2+ from mitochondria. Dibucaine (60 micro M), a clinically used local anaesthetic, inhibits both 45Ca2+ uptake an efflux. The results suggest that barbiturate stimulation of mitochondrial Ca2+ uptake may, in combination with effects on other Ca2+ sequestering processes, contribute to the inhibitor of transmitter release observed at a number of synapses. 相似文献
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The effects of regeneration on ecdysteroid levels and duration of the 10th larval instar of female house crickets were studied. Three experimental groups were used. The first consisted of larvae regenerating two legs cut off on the first day of this stage. The second group was made up of insects that underwent either an epidermal incision (sham-operated group I) or bleeding (sham-operated group II) at the same time as amputation in the first group. The last group was composed of normal insects.Larval stage length: in the first two groups, the duration of the 10th larval stage was significantly modified. It increased for regenerating animals as well as for sham-operated group I, but decreased for sham-operated group II.Ecdysteroid production: controls showed two periods of intense ecdysteroid activity. The first, which took place between days 4 and 6, was assumed to induce apolysis of the tegument and to render regeneration impossible (it coincided with the so-called critical period for regeneration). The second, which occurred between days 7 and 8 initiated cuticle synthesis. For sham-operated insects neither epidermal injury nor a loss of blood appear to change this hormonal profile significantly. Regenerating crickets however exhibited drastically reduced ecdysteroid peaks: the total apparent production of ecdysteriods was 50% below normal. Moreover, relative concentration of ecdysone to 20-hydroxy-ecdysone was greatly increased. Thus, regeneration obviously has a great and specific influence on ecdysteroid release in insect larvae. This effect may be related to changes observed in the prothoracic gland cycle which suggest that it plays a complex role in the regulation of the regenerative process. 相似文献
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