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2.
A. V. Shakhbazau G. A. Yakovleva I. A. Rod’kina N. A. Kartel 《Cytology and Genetics》2008,42(2):75-80
The pleiotropic effects of transgenesis includes different consequences of the insertion of a transgene that are not related to the direct action of its product. It is necessary to evaluate the outlook for the application in selection of the transgenic potato strain containing the bacterial chitinase gene chiA we created for studying the possible nonspecific influence of the introduction of the transgene on the phenotypical properties of the transgenic lines. In the present investigation we will consider the effect of the introduction of the chitinase transgene on such agronomically important characteristics as yield and nonspecific resistance. 相似文献
3.
N I Kalabukhov V A Serdiuk N V She?kina 《Zhurnal evoliutsionno? biokhimii i fiziologii》1976,12(6):532-538
In several geographic populations of the Arctic ground squirrel C. parryi, studies have been made on changes in oxygen consumption during decrease of the ambient temperature from 25 to 3-4 degrees, thermal preference, hemoglobin content of the blood and composition of the adipose tissue (both brown and white, subcutaneous and visceral). Significant shifts of these indices were found. In animals from various parts of the species area, different sensitivity to cooling was found, as indicated by determinations of oxygen consumption at different temperatures and the prefered temperature: different hemoglobin content of the blood was also found together with differences in the level of two unsaturated fatty acids - the oleic and linoleic ones. Comparison of these data with similar results obtained on various populations of the Siberian ground squirrel C. undulatus revealed obvious differences between these close species with respect to the indices studied. 相似文献
4.
E. Janchen A. Ginzberger K. Redinger Elise Hofmann B. Schussnig Fr. Knoll 《Plant Systematics and Evolution》1937,86(3):227-238
Ohne Zusammenfassung 相似文献
5.
V S Lushchekin E A Lushchekina K V Shule?kina N G Gladkovich 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1987,37(4):688-695
Study of development of early forms of behaviour was carried out on intact kittens of the first month of life, who endured in 5 days age uni- and bilateral sections of the lingual nerve, and on shame-operated and undernourished animals. It was shown that bilateral deafferentation caused significant disturbance of alimentary behaviour at the stage of sucking, manifested in disturbance of natural sucking and appearance of shame sucking, i.e. rhythmic sucking movement without nipple grasping. At the one-month age, in conditions of artificial feeding, natural sucking in operated animals was restored and the shame one disappeared. Bilateral section of the lingual nerve led to acceleration of ripening of sensory and motor systems and accelerated development of homing, exploratory and playing behaviour. Possible role is discussed of sensory trigeminal nuclei neurones in organization of normal patterned sucking and at limited sensory inflow. It is suggested that elimination of sensory input developing in the norm earlier than others, changes natural terms of other channels development, what accelerates the change of early behaviour forms. 相似文献
6.
Kulikov AV Bogatyrenko VR Likhtenshteĭn GI Allakhverdiev SI Klimov VV Shuvalov VA Krasnovskiĭ AA 《Biofizika》1983,28(3):357-362
The influence of Mn on saturation curves of ESR spectra of Ph(-) and P(+)(680) at 1-200K in samples with different content of Mn has been studied. An analysis of these data and those on photoinduced changes of fluorescence yield of chlorophyll leads to the conclusion that the Mn-containing centre in Photosystem 2 is a cluster of 4 Mn atoms, two of which can be replaced by Mg(2+) or any other divalent metal. The distances between Mn Na Ph as well as between Mn and P(680) have been estimated. 相似文献
7.
蚕豆叶片发育与衰老过程中超氧物歧化酶活性与丙二醛含量变化 总被引:2,自引:0,他引:2
蚕豆植株叶片随茎节自上而下表现出明显的发育与衰老顺序,可作为衰老特征的是叶绿素和蛋白质含量明显下降。蚕豆叶中SOD活性主要定位于12 000× g离心后所得的上清液和叶绿体组分。衰老叶片的SOD总活性和叶绿体组分的相对活性都有所下降,SOD同工酶谱也发生了改变。O_2~ 产生速率随叶龄增大而稍上升;而MDA含量在叶片外观表现枯黄衰老征兆前就急剧上升。可能因为衰老叶片过氧化氢酶活性大幅度下降与SOD之间的不平衡,致使O_2~ 代谢中间产物累积而引起膜的损伤. 相似文献
8.
We hypothesized that manganese deficient animals fed high vs moderate levels of polyunsaturated fat would either manifest
evidence of increased oxidative stress or would experience compensatory changes in antioxidant enzymes and/or shifts in manganese
utilization that result in decreased endogenous gut manganese losses. Rats (females in Study 1, males in Study 2,n = 8/treatment) were fed diets that contained 5 or 20% corn oil by weight and either 0.01 or 1.5 μmol manganese/g diet. In
study 2,54Mn complexed to albumin was injected into the portal vein to assess gut endogenous losses of manganese. The manganese deficient
rats:
Gut endogenous losses of manganese tended to account for a smaller proportion of absorbed manganese in rats fed high-fat diets;
otherwise fat intake had few effects on tissue manganese concentrations. 相似文献
1. | Had 30–50% lower liver, tibia, kidney, spleen, and pancreas manganese concentrations than manganese adequate rats; |
2. | Conserved manganese through ≈70-fold reductions in endogenous fecal losses of manganese; |
3. | Had lower heart manganese superoxide dismutase (MnSOD) activity; and |
4. | Experienced only two minor compensatory changes in the activity of copper-zinc superoxide dismutase (CuZnSOD) and catalase. |
9.
Pedro F. P. Brandão-Dias Daniel M. C. Hallack Elise D. Snyder Jennifer L. Tank Diogo Bolster Sabrina Volponi Arial J. Shogren Gary A. Lamberti Kyle Bibby Scott P. Egan 《Molecular ecology resources》2023,23(4):756-770
Environmental DNA (eDNA) analysis is a powerful tool for remote detection of target organisms. However, obtaining quantitative and longitudinal information from eDNA data is challenging, requiring a deep understanding of eDNA ecology. Notably, if the various size components of eDNA decay at different rates, and we can separate them within a sample, their changing proportions could be used to obtain longitudinal dynamics information on targets. To test this possibility, we conducted an aquatic mesocosm experiment in which we separated fish-derived eDNA components using sequential filtration to evaluate the decay rate and changing proportion of various eDNA particle sizes over time. We then fit four alternative mathematical decay models to the data, building towards a predictive framework to interpret eDNA data from various particle sizes. We found that medium-sized particles (1–10 μm) decayed more slowly than other size classes (i.e., <1 and > 10 μm), and thus made up an increasing proportion of eDNA particles over time. We also observed distinct eDNA particle size distribution (PSD) between our Common carp and Rainbow trout samples, suggesting that target-specific assays are required to determine starting eDNA PSDs. Additionally, we found evidence that different sizes of eDNA particles do not decay independently, with particle size conversion replenishing smaller particles over time. Nonetheless, a parsimonious mathematical model where particle sizes decay independently best explained the data. Given these results, we suggest a framework to discern target distance and abundance with eDNA data by applying sequential filtration, which theoretically has both metabarcoding and single-target applications. 相似文献
10.
Elise Flipse Marja G. M. Schippers Elly M. Janssen Evert Jacobsen Richard G. F. Visser 《Molecular breeding : new strategies in plant improvement》1996,2(3):211-218
Theamylose-free (amf) potato mutant can easily be complemented through introduction of the wild-type gene coding for granule-bound starch synthase (GBSS). After iodine staining the starch of theamf mutant is red whereas that of the wild type and the complementedamf mutant is blue. The level of complementation of selected transformants and their sexual off-spring after backcrossing withamf was investigated using sporophytic tuber cells and gametophytic microspore cells. Two diploid and two tetraploid transformants with full complementation demonstrated the expected segregation patterns of 1:1 (one active insert) or 3:1 (two independently segregating active inserts) in the microspores and in the F1 offspring based on staining of tubers. All expected genotypes in the F1 generation were found, based on microspore segregation patterns of the individual F1 plants. Two transformants with partial complementation (mixed phenotypes) were investigated. One of them, B1, was tetraploid and duplex for the GBSS insert, which had originated through mitotic doubling of the transformed diploid cells. In the F1 generation three phenotypic classes were found:amf, fully complemented and partially complemented. The latter two classes exist independently of a simplex or duplex gene status. The second transformant with partial complementation, B10, appeared to have a complex molecular composition. One cluster of five transgenes caused the partial complementation. Fully and partially complemented phenotypic classes were found after crossing B10 with theamf mutant. Indications were found that the ploidy level of the tissue in which the genes were introduced and expressed played an important role. Firstly, partial complementation was found after transformation of the diploid and not of the tetraploidamf genotypes. Secondly, the level of complementation was higher in tissue with lower ploidy levels, as illustrated by the colour of the starch inin vitro tubers (2x–4x cells) versus field-grown tubers (16x–64x). 相似文献