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In this study, cDNAs of two Erwinia carotovora-induced potato genes, designated Solanum tuberosumErwinia-induced-1 and 2 (Stei1 and Stei2) were isolated by differential display technique. Stei1 and Stei2 were detected in low copy number in the potato genome and found to encode putative proteins with no significant homology to any genes with known function. Treatment of the leaves with salicylic acid, methyl jasmonate and ethylene elevated neither Stei1 nor Stei2 mRNA levels. However, Stei1 and Stei2 expression were induced not only by E. carotovora but also by infiltration of water in leaves, albeit to a lesser extent. In addition, Stei2 was up-regulated by NaCl, wounding, dehydration and abscisic acid. Thus Stei1 and Stei2 define novel genes belonging to the family of those pathogenesis-related genes whose expression can be induced both by biotic and abiotic stresses.  相似文献   
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Outputs from the HadCM3 Global Climate Circulation Model according to scenarios A2 and B1 were used for climate change predictions in Lithuania. According to scenario A2, the annual temperature will increase by approximately 4.0 °C from 2061 to 2090, while scenario B1 predicts an increase of 2.0 °C. In contrast to scenario B1, scenario A2 predicts an annual increase in precipitation of 15–20 % at the end of the century. Based on the predicted climatic data for the two scenarios and climate maps by European Food Safety Authority for the EU, we created climate analogues for Lithuania for 2031–2060 and 2061–2090. These areas were overlain by the digital map of native tree species distributions in Europe, which was created from the European Forest Genetic Resources Programme database. If climate changes occur according to scenario B1, in 2031–2060, Lithuania’s climate will become suitable for approximately five to six alien species, such as Acer campestre, Acer pseudoplatanus, Fagus sylvatica, Populus nigra, and Prunus avium. In 2061–2090, these species will be joined by Sorbus domestica and Tilia platyphyllos. If climate changes occur according to scenario A2, at the end of the twenty-first century, Castanea sativa, Quercus pubescens, and Sorbus torminalis could expand this list. With respect to species dispersal rates, there is a high probability that the species A. campestre, A. pseudoplatanus, P. nigra, and P. avium will become immigrants to Lithuanian forests at the end of the twenty-first century. Approximately 20 new species native to Europe will be suitable for cultivation (scenario A2). Climate change will affect the distributions of native species too. An increase in the proportion of deciduous tree species (except Alnus incana) and some reduction in the proportion of conifers, Norway spruce (Picea abies) and Scots pine (Pinus sylvestris), are expected in Lithuanian forests.  相似文献   
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The aim of the present work was to determine peculiarities of accumulation of ionic state 137Cs in model experiments with seedlings of spring wheat (Triticum aestivum L., ??Nandu??) using laboratory experiments and to evaluate the complex effect of 137Cs ionizing radiation and geochemical factors on the growth of this plant. 137Cs accumulation in seedlings is influenced by the presence of mineral substances in the nutritional medium and by the conditions of illumination. Mineral substances (K+, Ca2+, Mg2+, Cu2+, NH 4 + , P5+, Fe3+) reduced the 137Cs accumulation coefficient of seedlings approximately three times. Addition of heavy metals as well as anionic group NO 3 ? to the growth medium caused insignificant changes in the level of radionuclide accumulation. In the model systems of RNA synthesis with wheat seedling cells nuclei isolated after complex treatment (in vivo) by 137Cs and HM showed clear inhibition of the RNA-polymerase II. This inhibition manifested itself as a complex effect of 137Cs ionizing radiation and heavy metals.  相似文献   
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In order to devise a method for rapid detection of ‘Candidatus (Ca.) Phytoplasma pini’ and for distinguishing it rapidly from other phytoplasmas, we carried out preliminary sequencing of Lithuanian ‘Ca. Phytoplasma pini’ strain PineBL2 using Illumina (NGS) technology and targeted sequencing employing universal phytoplasma primers. We focused on two resulting chromosomal segments that contained a 16S rRNA gene and a translation elongation factor EF‐TU gene (tuf), respectively. Based on alignments of the ‘Ca. Phytoplasma pini’ gene sequences with the corresponding sequences of other phytoplasmas, we designed new primer pairs for PCR‐based detection of ‘Ca. Phytoplasma pini’. Because ‘Ca. Phytoplasma pini’ strains are expected to reside in the pine phloem in a very low titre, one might expect that they could be detected only by nested PCR. By contrast, the primers and PCR protocols designed in the current work enabled rapid direct PCR detection and identification of ‘Ca. Phytoplasma pini ’ by amplifying a 484 bp 16S rDNA segment and a 513 bp tuf gene fragment that contain regions unique to this phytoplasma .  相似文献   
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Photosynthetic light harvesting in excess light is regulated by a process known as feedback deexcitation. Femtosecond transient absorption measurements on thylakoid membranes show selective formation of a carotenoid radical cation upon excitation of chlorophyll under conditions of maximum, steady-state feedback deexcitation. Studies on transgenic Arabidopsis thaliana plants confirmed that this carotenoid radical cation formation is correlated with feedback deexcitation and requires the presence of zeaxanthin, the specific carotenoid synthesized during high light exposure. These results indicate that energy transfer from chlorophyll molecules to a chlorophyllzeaxanthin heterodimer, which then undergoes charge separation, is the mechanism for excess energy dissipation during feedback deexcitation.  相似文献   
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OBJECTIVE: To develop an easy and safe method for catheterization and determine the pharmacokinetics of a single dose of enrofloxacin after intracoelomic administration in koi. DESIGN: Prospective study. ANIMALS: 20 healthy koi. PROCEDURE: 6 koi were anesthetized with tricaine methanesulfonate, and a 23-gauge, three-fourths-inch butterfly catheter was inserted into the coelomic cavity and secured. Catheters were flushed daily for 6 days with 0.4 mL of sterile saline (0.9% NaCl) solution containing heparin (100 units of heparin in 250 mL of saline solution) without removing koi from the aquarium. At the end of the sixth day (144 hours), each of the 6 catheterized koi and 6 uncatheterized (control) koi was anesthetized individually. Enrofloxacin (10 mg/kg [4.5 mg/lb]) was administered to catheterized koi via the injection port and to control koi via a 23-gauge needle in the same site as the catheter placement. A pharmacokinetics study was performed on multiple plasma samples to validate the efficiency of the catheter. Reliability of the catheterization method was determined in 8 koi. RESULTS: All 6 catheters remained patent and effective for the 6 days prior to the start of the pharmacokinetics study. Results for the 2 routes of administration were comparable, and all koi survived the study without any detectable clinical problems. CONCLUSIONS AND CLINICAL RELEVANCE: An intracoelomic catheter was effective and safe when maintained in koi for at least 6 days. This would be highly beneficial for veterinarians, clients, and fish, especially when intracoelomic administration of a drug would require daily or more frequent dosing.  相似文献   
8.
The primary structure of the major protein from the Corpuscles of Stannius (CS) of the Australian eel was elucidated from the cDNA sequence and was found to bear close similarity to the N-terminal amino acid sequence of the presumably homologous salmon hormone, teleocalcin (TC). The cDNA sequence predicted a preproprotein of 263 amino acids. Following removal of a 17 amino acid signal peptide, specific monobasic cleavage at an Arg-Phe bond generates the 231 amino acid mature form of the protein. The isolation and sequence determination of the prosequence confirms that the precursor contains a prosegment of 15 residues. Various fragments of the protein have been synthesized chemically and their biological activity assessed. The N-terminal 1–20 fragment of the mature protein inhibits calcium uptake in fingerling trout, the effect being similar, but not equipotent to salmon teleocalcin. Further, infusion of either the N-terminal 1–20 or the 81–94 fragment at 50 μg/h into the renal artery of conscious sheep, caused significant decreases in systemic plasma potassium concentration and in potassium excretion. The 1–20 fragment also gave rise to a small but significant increase in sodium excretion. Infusion of TC at the same rate results in a significant decrease in plasma potassium and phosphate concentration as well as a significant decrease in potassium excretion. Bovine PTH (1–34) at 100 μg/h causes a small decrease in plasma potassium and phosphate and an increase in plasma calcium concentration, and was the only peptide to cause a significant decrease in calcium excretion.  相似文献   
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