A review of approximately 30 published reports on fossil diatoms older than Cretaceous is presented. Together with the Proterozoic diatom remnants found in Poland thirty years ago, the latest unquestionable finds of Cambrian diatoms (Vologdin 1962, Allison and Hilgest 1986, Gapeev 1992, 1995) and the recent report of the partial diatom provenance of siliceous grains in Late Devonian shales (Schieber et al. 2000) make these discoveries reliable.
In the Phycological Departament of the W. Szafer Institute of Botany, Polish Academy of Sciences in Cracow, material essential for the proper assignment of the algal flora found in Poland have been gathered. Among them is the collection of original publications and separata (or their copies) concerning the contemporary and fossil algae as well as the bibliography on the Polish algal flora. On this basis, the indices of taxa found in Poland belonging to all prokaryotic and eukaryotic systematic groups of algae, initially in the form of files, now stored on computers, are elaborated. After publication of the bibliographies (Sieminska 1990, Sieminska and Pajak 1995), successive indices will be issued. The one concerning the blue-green algae mentioned in literature up to 1980 has already been published (Sieminska 1995), a continuation (up to 1990) is already for print and so is the fascicle concerning diatoms (total, up to 1990). Each index contains the list of Latin names of the genera and species given in alphabetical order. Latin names of the lower systematic units are placed below, also alphabetically, irrespective of their rank. The names of author (authors) usually written next to the Latin of a taxon are omitted because of the fact that they are very often inconsistently cited and sometimes concern different taxa. The taxon name is followed by the numbers of the references in which it has been mentioned in the bibliographies. Next to each number, the symbol of the kind of information is given (in parentheses); drawings and photos, i.e. illustrations (i), complementary remarks concerning size or morphology (u), and description (n) of the new taxon. The data which have been elaborated diligently for more than 40 years thus far and the published indices create a base facilitating floristic and physiographic studies as well as the preparation of monographs, till now non-existing, on the representatives of particular systematic groups of contemporary and fossil algae in Poland. For the phycologists from other countries, the indices provide information on the components of Polish flora, in particular the rarely occurring taxa. The subsequent fascicles will be published - similarly as the first one - simultaneously in English and Polish. The indices, as well as the bibliographies, may be purchased at the publisher office, which is the W. Szafer of Botany P.A.Sc., Cracow, Lubicz 46.
Inhibition of nitric oxide synthase (NOS) by Nitro-L-arginine-methyl-ester in 16 male Wistar rats anaesthetized with urethane, paralysed and artificially ventilated, increased siginficantly local peripheral vascular resistance in the parietal cortex (CVR) along with augmentatoin of the mean arterial blood presure (MP) and no change of the local cerebrocortical blood flow (CBF) recorded with a Laser-Doppler-Flowmeter.In 11 rats L-NAME reversed a pressor effect of brief hypercapnia induced by 10% Co2/air mixture into depressor esponse,reduced CBF esponse proportionally to the reduction of MAP and did notinfluence CVR response to CO2. In 5 rats L-NAME did not abolish the central pressor effect of CO2-stimulus and significantly augmented CO2-induced vasodilatory response in the cortex by a larger reduction of CVR.It is concluded that NO does not mediate the vasodilatory effect of brief hypercapnia in the cortex.NO apears critical for the central pressor effect of CO2.In those rats in which the central pressor effect of a CO2-stimulus was not abolished by an NOS blocker, an increased CBF and augmented decrease in CVR was observed during brief hypercapnia.Possible mechanisms of this dual responsiveness of cortical blood flow and arterial blood pressure to CO2, induceds bu inhibition of NOS, are discussed.
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