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121.
Nina Šraj-Kržič Mateja Germ Olga Urbanc-Berčič Urška Kuhar Georg A. Janauer Alenka Gaberščik 《Plant Ecology》2007,192(1):107-118
The quality of the aquatic environment and macrophytes were surveyed in the case of the remarkable karstic river Ljubljanica
s. lat. (Slovenia). It consists of seven intermittent and permanent surface watercourses, connected by groundwater flows. We assessed
11 parameters describing the land use beyond the riparian zone, the structure of the riparian zone and stream channel morphology,
as well as the distribution and abundance of macrophytes. The intermittent watercourses exhibited a relatively high level
of naturalness, because the variable water regime prevents intensive human activity. Greater influence of the human activity
on the permanent watercourses resulted in a modified riverine environment. The share of different ecological groups of macrophytes,
i.e. submerged, emerged and amphibious species, reflected the water regimes of the different watercourses. A total of 62 taxa
of macrophytes were identified in about 100 km of length examined. Of these, amphibious macrophytes dominated as a consequence
of intermittent water regime. The relationship between environmental parameters and macrophytes, and the effects of the intermittent
hydrology were investigated. All environmental parameters explained 28% of the variance in the distribution of macrophytes
in watercourses, as determined by canonical correspondence analysis. Completeness of the riparian zone, bank undercutting
and sediment accumulation were found to be the most influential. 相似文献
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123.
Jurassic neptunian dikes are common within Upper Triassic to Lower Jurassic platform limestone of the Julian Alps. At Mt Mangart,
the following geometries were observed: irregular dissolution cavities, thin penetrative fractures, larger fractures with
sharp sidewalls, and laterally confined breccia bodies. Inside a complex neptunian dike system two main generations of infillings
were differentiated. The first generation is heterogeneous and consists of bioclastic limestones, representing uniquely preserved
sediments subdivided into five different microfacies. The second generation is more common and typically consists of coarse-grained
breccias with host-rock clasts and marly limestone matrix containing echinoderms. Fracture formation and void filling of the
first generation of neptunian dikes is dated as Pliensbachian and is interpreted to be caused by the Julian carbonate platform
dissection due to widely recognized Lower Jurassic Tethyan rifting. The timing of formation for the second generation is only
broadly constrained, ranging from the Pliensbachian to the Late Cretaceous. 相似文献
124.
Predrag Sikiric Sven Seiwerth Gorana Aralica Darko Perovic Mario Staresinic Tomislav Anic Miroslav Gjurasin Ingrid Prkacin Jadranka Separovic Dinko Stancic-Rokotov Martina Lovric-Bencic Darko Mikus Branko Turkovic Ivo Rotkvic Stjepan Mise Rudolf Rucman Marijan Petek Tihomil Ziger Bozidar Sebecic Zoran Ivasovic Vjekoslav Jagic Ljiljana Komericki Ivan Balen Alenka Boban-Blagaic Ivo Sjekavica 《Journal of Physiology》2001,95(1-6):283-288
After demonstration that cysteamine induced duodenal lesions in gastrectomized rats, while a number of antiulcer drugs mitigated these lesions, it was shown that one single intrarectal (i.r.) cysteamine application produced severe colon lesions in acute studies in rats. Thus, the further focus was on the protracted effect of cysteamine challenge (400 mg/kg b.w. i.r.) and therapy influence in chronic experiments in female rats. Regularly, cysteamine colon lesions were markedly mitigated by ranitidine (10), omeprazole (10), atropine (10), methylprednisolone (1), sulphasalazine (50; mg/kg), pentadecapeptide BPC 157 (PL-10, PLD-116; 10 microg or 10 ng/kg). Specifically, after 1 or 3 months following initial challenge (cysteamine 400 mg/kg i.r.) in female rat, the therapy [BPC 157 (PL-10, PLD-116 (10.0 microg or 10.0 ng/kg; i.g., i.p., i.r.), ranitidine, omeprazole, atropine, methylprednisolone, sulphasalazine (i.p.)] reversed the protracted cysteamine colon injury: the 1 week-regimen (once daily application) started after 1 month post-cysteamine, as well as the 2 weeks-regimen (once daily application), which started after 3 months. The effect on recidive lesion was also tested. These cysteamine lesions may reappear after stopping therapy (after stopping therapy for 3 weeks at the end of 2-weeks regimen started in 3 months-cysteamine female rats) in sulphasalazine group, while this reappearance is markedly antagonized in pentadecapeptide BPC 157 (PL-10, PLD-116)-rats (cysteamine-colon lesion still substantially low). 相似文献