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31.
Antonín Vězda 《Folia Geobotanica》1987,22(1):71-83
Nine species ofByssoloma Trevisan (Pilocarpaceae) are reported from a collection of foliicolous lichens from Zaire, and includeB. murinum sp. n. In addition,B. usambarense sp. n. is described from adjacent Tanzania. A determination key is provided to all the known African species, and each species is briefly characterized. 相似文献
32.
Anton F. Post 《Archives of microbiology》1986,145(4):353-357
Transitions in growth irradiance level from 92 to 7 Em-2 s-1 and vice versa caused changes in the pigment contents and photosynthesis of Oscillatoria agardhii. The changes in chlorophyll a and C-phycocyanin contents during the transition from high to low irradiance (HL) were reflected in photosynthetic parameters. In the LH transition light utilization efficiencies of the cells changed faster than pigment contents. This appeared to be related to the lowering of light utilization efficiencies of photosynthesis. As a possible explanation it was hypothesized that excess photosynthate production led to feed back inhibition of photosynthesis. Time-scales of changes in the maximal rate of O2 evolution were discussed as changes in the number of reaction centers of photosystem II in relation to photosynthetic electron transport. Parameters that were subject to change during irradiance transitions obeyed first order kinetics, but hysteresis occurred when comparing HL with LH transients. Interpretation of first order kinetic analysis was discussed in terms of adaptive response vs changes in growth rate.Non-standard abbreviations Chla
chlorophyll a
- CPC
C-phycocyanin
- PS II
photosystem II
- PS I
photosystem I
- RC II
reaction center of photosystem II
- P
photosynthetic O2-evolution
- I
irradiance, Em-2 s-1
-
light utilization efficiency of cells, mmol O2·mg dry wt-1·h-1/Em-2 s-1
-
light utilization efficiency of photosynthetic apparatus, mol O2·mol Chla
-1·h-1/Em-2 s-1
- Pmax
maximal rate of O2 evolution by cells, mol O2·mg dry wt-1·h-1
- Pmax
maximal rate of O2 evolution by photosynthetic apparatus, mol O2·mol·Chla
-1·h-1
- LL
low light, E m-2 s-1
- HL
high light, E m-2 s-1
- LH
low to high light transition
- HL
high to low light transition
-
k
specific rate of adaptation, h-1
-
specific growth rate, h-1
-
Q
pool size of cell constituent, mol·mg dry wt-1
-
q
net synthesis rate of cell constituent, mol·mg dry wt-1·h-1 相似文献
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36.
Antonín Vězda 《Folia Geobotanica》1970,5(3-4):307-337
Es werden 28 Arten von lichenisierten Fungi (Flechten) mit kritischen taxonomischen Hinweisen oder Ergänzungen zu den in der Literatur vorhandenen Beschreibungen, oft mit chorologischen Bemerkungen und Angaben über die ökologischen Verhältnisse ihrer Standorte angeführt, von denen die nachgenannten Arten und Namenskombinationen neu sind:Verrucaria scabra Vězda sp. n.,Geisleria xylophila Vězda sp. n.,Toninia steineri Poelt etVězda sp. n.,Pachyascus byssaceus (Vězda) Vězda comb. n. undMicarea gomphillacea (Nyl.) Vězda comb. n. 相似文献
37.
Summary Carbonyl cyanide m-chlorophenylhydrazone (CCCP) and pentachlorophenol (PCP), two powerful uncouplers of phosphorylation, specifically inhibit the assimilation of nitrite in the course of nitrate reduction. These results support our former conclusion that high-energy phosphate is involved in the metabolism of nitrite. 相似文献
38.
Antonín Vězda 《Folia Geobotanica》1966,1(1):311-340
Im Artikel wird die ursprüngliche Gattungsdiagnose derGyalidea Lett. um die Merkmale der Pilzkomponente ergänzt. Die angenommenen verwandtschaftlichen Beziehungen derGyalidea zu der FamilieAsterothyriaceae werden diskutiert. Alle bisher festgestellten Arten mit Übersichten der revidierten Proben werden kurz beschrieben. Neue Taxa und Kombinationen:Gyalidea dodgei spec. n.,G. epiphylla spec. n.,G. mayaguezensis spec. n.,G. portoricensis spec. n.,G. fritzei (Stein) comb. n.,G. fritzei var.rivularis (Eitn.) comb. n.,G. hyalinescens (Nyl.) comb. n.,G. lecideopsis var.convarians (Nyl.) comb. n.,G. lecideopsis var.stigmatoides (Nyl.) comb. n.,G. mexicana (B. de Lesd.) comb. n. undG. subscutellaris (Vězda) comb. n. 相似文献
39.
Antonín Vězda 《Folia Geobotanica》1967,2(4):383-396
Eine taxonomische Studie über die GattungSagiolechia Massal. als wieter Teil einer Revision der FamilieGyalectaceae sensuZahlbruckner wird vorgelegt. 相似文献
40.
Bernard J. Van Vliet Arie H. Mulder Anton N. M. Schoffelmeer 《Journal of neurochemistry》1990,55(4):1274-1280
The receptors mediating the inhibition of D1 dopamine receptor-stimulated adenylate cyclase by opioids were examined in primary cultures of rat neostriatal neurons. Adenylate cyclase activity was dose-dependently increased by the selective D1 dopamine receptor agonist SKF 38393 (EC50 = 0.05 microM). This stimulation was fully antagonized by the selective D1 dopamine receptor antagonist SCH 23390 (1 microM). SKF 38393 (1 microM)-stimulated adenylate cyclase activity was strongly reduced (by almost 60%) by the highly selective mu-agonist [D-Ala2, MePhe4, Gly-ol5]-enkephalin (DAGO; EC50 = 0.006 microM) and high concentrations of the selective delta-agonist [D-Ser2(O-tert-butyl), Leu5]-enkephalyl-Thr6 (DSTBU-LET; EC50 = 0.13 microM) but not by the selective delta-agonist [D-penicillamine2, D-penicillamine5]enkephalin (DPDPE). D1 dopamine receptor-stimulated adenylate cyclase activity was also slightly reduced (by approximately 20%) by high concentrations of the kappa-agonist U50,488 (EC50 = 0.63 microM). The inhibitory effects of submaximally effective concentrations of DAGO, DSTBULET, and U50,488 were equally well antagonized by the mu-opioid receptor-selective antagonist naloxone (EC50 of approximately 0.1 microM). Neither the irreversible delta-ligand fentanyl isothiocyanate (1 microM) nor the reversible delta-antagonist ICI 174864 (1 microM) reversed the inhibitory effects of DSTBULET. The inhibitory effects of DAGO and U50,488 were equally well reversed by high concentrations (greater than 0.1 microM) of the kappa-opioid receptor-selective antagonist norbinaltorphimine. The effect of DAGO (1 microM) was already detectable after 1 day in culture, whereas DPDPE (1 microM) had no effect even after 28 days in culture. These data indicate that an homogeneous population of mu-opioid receptors coupled as inhibitors to D1 dopamine receptor-stimulated adenylate cyclase is expressed in rat neostriatal neurons in primary culture. 相似文献