Stať má dvě části: po typologickém úvodu autor v prvé části zkoumá úlohu životnosti při formovaní aktivní větné perspektivy v PrelE. V druhé části se zabýva frekvencí pádových forem. Autor si je vědom rozdílu mezi první systémově-strukturní a druhou kvantitativní částí stati. Konstatuje, že v dosavadním jazykovědném bádání bývají oba přístupy nedostatečně propojeny, což má mimo jiné příčinu v dosud značně oddělovaném myšlení o langue a o parole. Následkem toho pak systémové analýzy nejsou vždy doplňovány zcela paralelními výzkumy kvantitativními. Stať podle autora ukazuje, že kvantitativní analýzy mají zásadní význam pro porovnávání jazyků. Frekvence je jeden ze základních faktorů, které prostupují i typologii gramatických kategorií. Zanedbávání soustavného kvantitativního výzkumu neprospívá ani vývojovým, ani komparatistickým výzkumným programům.
A double ínductíon mechanism of Dl protein degradatíon in isolated photosystem 2 (PS2) core complexes and reaction centres is described, showing the existence of two potentíal sites for primáty cleavage. Donor side inhibition conditi- o n s (presence of electron acceptors but no electron donors and pH 8.0) trigger the hydrolysis of the Dl protein between the putatíve helices 1 and II on the lumenal side of the thylakoid membrane. This results in the generation of a C-terminal 24 kDa fragment. However, when the donor-side is actíve (presence of electron donors but no electron acceptors and pH 6.0, acceptor side inhibition conditions) both preparations are able to produce a N-terminal 23 kDa fragment, indicating cleavage between helices IV and V, on the stromal side of the membrane.
Two distinct hemocyte populations are determined in the hemolymph of the triatomine bug Triatoma infestans Klug, oenocytoids and plasmatocytes, and their independent origin from separate stem cells is shown. Both hemocyte populations differ considerably in their morphology, ultrastructure and lectin-binding properties. While oenocytoids are quite uniform with easily definable cells which do not to bind any assayed lectin, the plasmatocytes are a very polymorphic population possessing several morphological types and displaying a positive reactivity with lectins.
High (HI, 200 W m'^) and low (LI, 30 W m"^) irradiance treatments on the cells of cyanobactenum Synechococcus elongatus Nfig., var. thermalis Geitl. strain KOVROV 1972/8 were perfonned in the presence of chloramphenicol (CAP), and with addition of DCMU and hydroxylamine (HA), respectively, at growth (56 °C) and low (20 °C) temperatures, to distínguish allegedly different mechanisms of PS 2 photoinactivation (PS 2 PI). At both temperatures HI caused a decline of Fy and Hill reaction activity (HRA) followed by degradation of Dl and to a lesser extent also D2 protein. Fq increased slowly during irradiance at 56 while at 20 ®C it quickly rose to constant level. Degradation of proteins was slowed at a lower temperature. The presence of DCMU during photoinhibition significantly blocked the Fq rise and also prevented PS 2 protein degradation at both temperatures. The course of PS 2 PI under LI resembled tlmt, observed at HI, but changes were much slower. During irradiation of the cells, in which oxygen evolving complex (OEC) was impaired by HA, we observed: (/) at least a ten-fold faster decline of PS 2 electron transport activity than in the cells vňth fimctional OEC under the same conditions; (2) an extensive degradation not only of Dl and D2, but also of the apoprotein of chlorophyll-protein CP43 {ACP43y, (3) almost complete inhibition of PS 2 protein degradation in the presence of DCMU. Thus under all conditions tested in vivo which do not affect the fimction of OEC, the fimction of OEC, PS 2 PI proceeds via the acceptor side and a fimctional impairment of OEC is necessary for induction of the donor side mechanism. When OEC is impaired (e.g. by HA) this mechanism can come in action.
Examination of freshwater fishes from the Parana River in southern Brazil during March 1992, revealed the presence of two new, previously undescribed species of the genus Goezia: G. brasiliensis sp. n. is described from the stomach of Brycon hilarii (family Characidae) (type host) and the intestine of Pseudoplatystoma coruscans (Pimelodidae) and it is characterized mainly by the length (0.802 mm) of spicules, number and arrangement of male caudal papillae (10 pairs of preanals and 4 pairs of postanals) and body measurements (male 11 mm, female 10-16 mm); the main characteristics of G. brevicaeca sp. n„ described from the stomach of Brycon hilarii, are a short anterior intestinal caecum reaching anteriorly only to the posterior end of oesophagus, comparatively short spicules (0.367 mm), number of male caudal papillae (20 pairs of preanals and 4 pairs of postanals) and an elongate, rather long body (male 17 mm, female 23 mm).