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51.
Mats Thulin 《Nordic Journal of Botany》1993,13(1):49-50
It is argued that the original material of Maerua macrocarpa consists of elements from three different species: M. denhardtiorum, Thilachium thomasii and Capparis tornentosa . A lectotypification is proposed that makes M. macrocarpa a synonym of M. denhardtiorum . 相似文献
52.
53.
Gunilla Lindmark Stig Melander Bo A. Nilsson Göran Zador 《Prostaglandins & other lipid mediators》1973,3(4):481-489
As a consequence of great individual variations among pregnant women in their response to prostaglandin medication, overstimulation of the uterus might occasionally occur. The need of a drug which could safely prevent excessive and undesirable prostaglandin-induced uterine contractions is therefore apparent.Two β-mimetic adrenergic compounds, orciprenaline and ritodrine, were tested with respect to their ability to reduce prostaglandin-induced uterine activity. Both compounds have successfully depressed the intensity, as well as the frequency of uterine contractions, which were previously induced by intrauterine administration of prostaglandin F2α. With both drugs the reduction in uterine activity was closely dose-related and accompanied by a considerable increase in the maternal heart rate. While orciprenaline did not alter the maternal blood pressure, ritodrine produced a rise in systolic, and a fall in diastolic pressure. No other side effect was recorded. When the infusion ceased, uterine activity increased in various degrees.On the basis of the present findings the possible role of prostaglandins in the physiological regulation of the uterine contractions during pregnancy is discussed. 相似文献
54.
Methanol production resulting from the demethoxylation of lignin-related substances by Phanerochaete chrysosporium K-3 was studied in the presence or absence of glutamic acid in order to determine if methanol formation involved the ligninolytic system of the fungus. The general pattern was that methanol formation, calculated as percentage of theoretical yield, decreased in the order guaiacyl > syringyl > veratryl (3,4-dimethoxy) compounds. Methoxyhydroquinone and vanillic acid were most easily demethoxylated, while methanol production decreased with increasing molecular weight for the same type of structure (i.e. guaiacyl). Glutamic acid inhibited the demethoxylation of many of the compounds tested. The demethoxylation of the 4-methoxy group of veratric acid was particularly inhibited by glutamic acid suggesting a participation of the ligninolytic system, while the 3-methoxy group was influenced to a lesser extent.
The demethoxylating enzyme acting on lignin-related phenols is probably a peroxidase, while the identity of the enzyme demethoxylating dimethoxy compounds is not known with certainty, although a peroxidase type of enzyme reaction is anticipated also here. 相似文献
The demethoxylating enzyme acting on lignin-related phenols is probably a peroxidase, while the identity of the enzyme demethoxylating dimethoxy compounds is not known with certainty, although a peroxidase type of enzyme reaction is anticipated also here. 相似文献
55.
The rapidly growing body of sequenced DNA demands efficientcomputer programs for its analysis and storage. The programdescribed in this paper, SEQ-ED, has been designed to handlea large number of DNA sequences up to 200 kilobases [kb] longstored in a sequence library. In order to minimize the requiredstorage space, the sequences are stored in a compressed formatusing three binary digits per base. In the development of thisprogram, special care has been given to make it easy to usefor molecular biologists without any previous computer experience.
Received on September 10, 1984; accepted on October 30, 1984 相似文献
56.
Lars Lundin Torbjörn Nilsson Sabine Jordan Elve Lode Monika Strömgren 《Wetlands Ecology and Management》2017,25(4):405-419
Restoration of wetlands is a high priority world-wide. Peat extraction areas can be restored by rewetting, however affecting the environment. It could be expected to turn the drained peat-cutover area from a source to a sink of most elements. This study examined effects of such rewetting on peat, hydrology and water chemistry over 15 years at two sites in Sweden; the nutrient-poor Porla peatland and the nutrient-rich Västkärr peatland. Rewetting caused minor changes to peat chemistry, but at the Västkärr site ammonium concentrations increased in superficial peat layers while nitrate decreased. In terms of hydrology, rewetting of the Porla site decreased annual runoff and both high and low discharges. Water pH at the Porla site stayed fairly stable, but at the Västkärr site pH, after an initial 4 years dip, gradually increased to higher values than before rewetting. Water colour and organic matter content were fairly stable, but slightly lower values were found after 15 years than in initial 4–5 years. The concentrations of base cations and of inorganic N were lower after rewetting, while total P was higher. However, these impacts could change from an initial phase as the wetlands in the long-term perspective develop into mires. 相似文献
57.
Salmonella/microsome mutagenicity of monochloro derivatives of some di-, tri- and tetracyclic aromatic hydrocarbons 总被引:1,自引:0,他引:1
A series of 8 monochloroarenes have been tested for mutagenicity in the Salmonella/microsome assay. None of the compounds was detectably active in the absence of mammalian activation whereas, depending on structure, some of the compounds were mutagenic in its presence having responses higher than those reported for the parent compounds. 相似文献
58.
O L Segal V N Mats I V Bobrova 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1989,(5):59-64
The protein content has been determined by means of cytointerferometry in neurons of fields CA-1 and CA-3 of the dorsal hippocampus in rats, which were trained in a conditioned reflex of two-way avoidance (CRTA) with the action of subcutaneously injected enkephalin cyclic analogue (ECA) in a dose 10 mkg. It has been found that after ECA injection the protein content in the neuronal nuclei of the hippocampal CA-3 field reduces. The acceleration of the CRTA elaboration occurring during the action of ECA is accompanied by a drastic increase of the protein content in the neuronal nuclei of the CA-3 field. The ECA administration to the rats of the active control groups to which were presented the same number of unpaired conditioned and unconditioned stimuli as during the CRTA elaboration also enhances the protein content in the neurons of the CA-3 field. The rats of all investigated groups in the neurons of the CA-1 field display no such significant shifts. The conclusion has been drawn that ECA produces a regulating influence on protein metabolism in hippocampal neurons depending on their functional state. 相似文献
59.
Per Fahlberg Nathalie Buhot Oskar N. Johansson Mats X. Andersson 《Molecular Plant Pathology》2019,20(1):69-77
Non-specific lipid transfer proteins (LTPs) are involved in the transport of lipophilic compounds to the cuticular surface in epidermal cells and in the defence against pathogens. The role of glycophosphatidylinositol (GPI)-anchored LTPs (LTPGs) in resistance against non-host mildews in Arabidopsis thaliana was investigated using reverse genetics. Loss of either LTPG1, LTPG2, LTPG5 or LTPG6 increased the susceptibility to penetration of the epidermal cell wall by Blumeria graminis f. sp. hordei (Bgh). However, no impact on pre-penetration defence against another non-host mildew, Erysiphe pisi (Ep), was observed. LTPG1 was localized to papillae at the sites of Bgh penetration. This study shows that, in addition to the previously known functions, LTPGs contribute to pre-invasive defence against certain non-host powdery mildew pathogens. 相似文献
60.
Anna Trnroos Laurene Pecuchet Jens Olsson Anna Grdmark Mats Blomqvist Martin Lindegren Erik Bonsdorff 《Global Change Biology》2019,25(4):1235-1246
The rate at which biological diversity is altered on both land and in the sea, makes temporal community development a critical and fundamental part of understanding global change. With advancements in trait‐based approaches, the focus on the impact of temporal change has shifted towards its potential effects on the functioning of the ecosystems. Our mechanistic understanding of and ability to predict community change is still impeded by the lack of knowledge in long‐term functional dynamics that span several trophic levels. To address this, we assessed species richness and multiple dimensions of functional diversity and dynamics of two interacting key organism groups in the marine food web: fish and zoobenthos. We utilized unique time series‐data spanning four decades, from three environmentally distinct coastal areas in the Baltic Sea, and assembled trait information on six traits per organism group covering aspects of feeding, living habit, reproduction and life history. We identified gradual long‐term trends, rather than abrupt changes in functional diversity (trait richness, evenness, dispersion) trait turnover, and overall multi‐trait community composition. The linkage between fish and zoobenthic functional community change, in terms of correlation in long‐term trends, was weak, with timing of changes being area and trophic group specific. Developments of fish and zoobenthos traits, particularly size (increase in small size for both groups) and feeding habits (e.g. increase in generalist feeding for fish and scavenging or predation for zoobenthos), suggest changes in trophic pathways. We summarize our findings by highlighting three key aspects for understanding functional change across trophic groups: (a) decoupling of species from trait richness, (b) decoupling of richness from density and (c) determining of turnover and multi‐trait dynamics. We therefore argue for quantifying change in multiple functional measures to help assessments of biodiversity change move beyond taxonomy and single trophic groups. 相似文献