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排序方式: 共有142条查询结果,搜索用时 15 毫秒
1.
In the experiments performed on kidneys of 5 species of marine Teleostei, morphological peculiarities in secretion of 8 fluorescent organic acids (uranin, primulin, tripaphlavin, erythrosin etc.) and in 5 organic bases (rhodamin C, auramin etc.) have been studied. At a very low concentration in the incubation medium--about 0.005 mg/ml--the substances mentioned penetrate into the epithelial cell of the canaliculus; its weak fluorescence appears, and soon they begin to be excreted in great amount through the apical part of the plasmolemma and accumulated in the canalicular lumen. All the substances studied accumulate in the cell and only some of them (uranin, primulin, titanic yellow, etc.) are secreted into the canalicular lumen. Penicillinum and probenecide inhibit penetration of the organic acids into the cell through the basal membrane. Uranin secretion into the canalicular lumen is inhibited in the presence of furocemid; amilorid, magnium and sulfate ions do not influence secretion of the organic acids. Secretion of the organic bases does not change when paraaminohippuric acid and furocemid are added to the medium, but it decreases when concentration of magnium ions increases. 相似文献
2.
The catecholamine content was quantitated and acetylcholinesterase activity determined in rat brain locally exposed to laser radiation. It was shown that the adrenaline/noradrenaline ratio changed in the tissues under study and the cholinergic system was involved in the abscopal effect of laser radiation. 相似文献
3.
A highly conserved nuclear gene for low-level phylogenetics: elongation factor-1 alpha recovers morphology-based tree for heliothine moths 总被引:8,自引:2,他引:6
Cho S; Mitchell A; Regier JC; Mitter C; Poole RW; Friedlander TP; Zhao S 《Molecular biology and evolution》1995,12(4):650-656
Molecular systematists need increased access to nuclear genes. Highly
conserved, low copy number protein-encoding nuclear genes have attractive
features for phylogenetic inference but have heretofore been applied mostly
to very ancient divergences. By virtue of their synonymous substitutions,
such genes should contain a wealth of information about lower-level
taxonomic relationships as well, with the advantage that amino acid
conservatism makes both alignment and primer definition straightforward. We
tested this postulate for the elongation factor-1 alpha (EF-1 alpha) gene
in the noctuid moth subfamily Heliothinae, which has probably diversified
since the middle Tertiary. We sequenced 1,240 bp in 18 taxa representing
heliothine groupings strongly supported by previous morphological and
allozyme studies. The single most parsimonious gene tree and the
neighbor-joining tree for all nucleotides show almost complete concordance
with the morphological tree. Homoplasy and pairwise divergence levels are
low, transition/transversion ratios are high, and phylogenetic information
is spread evenly across gene regions. The EF-1 alpha gene and presumably
other highly conserved genes hold much promise for phylogenetics of
Tertiary age eukaryote groups.
相似文献
4.
5.
Kulikov A. A. Nasluzova E. V. Dorofeeva N. A. Glazova M. V. Lavrova E. A. Chernigovskaya E. V. 《Journal of Evolutionary Biochemistry and Physiology》2021,57(2):304-318
Journal of Evolutionary Biochemistry and Physiology - One of the main challenges of modern neurobiology is finding approaches to prevent structural abnormalities in the brain, specifically, in the... 相似文献
6.
AV Shevchenko IG Budzanivska TP Shevchenko VP Polischuk D Spaar 《Archives Of Phytopathology And Plant Protection》2013,46(2):139-146
The work was focused on the investigation of possible dependencies between the development of viral infection in plants and the presence of high heavy metal concentrations in soil. Field experiments have been conducted in order to study the development of systemic tobacco mosaic virus (TMV) infection in Lycopersicon esculentum L. cv. Miliana plants under effect of separate salts of heavy metals Cu, Zn and Pb deposited in soil. As it is shown, simultaneous effect of viral infection and heavy metals in tenfold maximum permissible concentration leads to decrease of total chlorophyll content in experiment plants mainly due to the degradation of chlorophyll a. The reduction of chlorophyll concentration under the combined influence of both stress factors was more serious comparing to the separate effect of every single factor. Plants' treatment with toxic concentrations of lead and zinc leaded to slight delay in the development of systemic TMV infection together with more than twofold increase of virus content in plants that may be an evidence of synergism between these heavy metal's and virus' effects. Contrary, copper although decreased total chlorophyll content but showed protective properties and significantly reduced amount of virus in plants. 相似文献
7.
Vorob'eva OV Romanenkov AS Metelev VG Kariagina AS Lavrova NV Oretskaia TS Kubareva EA 《Molekuliarnaia biologiia》2003,37(5):906-915
DNA duplexes containing a single phosphoryldisulfide link in place of the natural internucleotide phosphodiester bond were employed in affinity modification of Cys142 in cytosine-C5 DNA methyltransferase SsoII (M.SsoII). The possibility of duplex-M.SsoII conjugation as a result of disulfide exchange was demonstrated. The crosslinking efficiency proved to depend on the DNA primary structure, modification position, and the presence of S-adenosyl-L-homocysteine, a nonreactive analog of the methylation cofactor. The SH group of M.SsoII Cys142 was assumed to be close to the DNA sugar-phosphate backbone in the DNA-enzyme complex. 相似文献
8.
M. I. Sysoeva V. V. Lavrova E. M. Matveeva E. G. Sherudilo L. V. Topchieva 《Russian Journal of Plant Physiology》2011,58(6):999-1004
Effect of short-term (2 h a day) and long-term (6 days) exposure to low temperature (5°C) on cold tolerance was investigated
in two cultivars of potato (Solanum tuberosum L.): resistant (Sudarynya) and susceptible (Nevskii) to potato cyst nematode (Globodera rostochiensis Woll.). The extent of their infestation and changes in the expression of the genes of resistance to nematode (H1 and Gro1-4) were also analyzed. In both cultivars, exposure to low temperature enhanced cold resistance of potato plants. Enhancing
cold resistance of cv. Sudarynya induced by a short-term exposure to chilling did not affect the extent of nematode infestation,
whereas in susceptible cv. Nevskii, the extent of infestation decreased by almost three times. The level of expression of
H1 gene in the leaves of the susceptible cultivar rose almost twofold both after short-term and long exposure to chilling, while
in the resistant cultivar, gene expression increased only after a short-term effect of cold. The level of Gro1-4 gene expression increased after both temperature treatments only in the resistant cv. Sudarynya. Thus, the expression of
genes for potato resistance to nematode infestation became more active in the susceptible cultivar as regards the gene H1 and in the resistant cultivar, regarding the gene Gro1-4. In the nematode-susceptible cv. Nevskii, the level of infestation decreased and cold resistance increased, apparently indicating
cross adaptation to two factors of different nature. 相似文献
9.
Donina ZhA Lavrova IN Tikhonov MA Kotov AN Kolesnikov VI Baranov VM 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2005,91(9):1091-1096
In ground-based model of the hemodynamics effects of weightlessness, the intersystem relation of breathing and circulation was investigated during inspiration and expiration separately in anesthetized catz. It's shown that the dynamics of central venous pressure, esophageal pressure and filling pressure of the heart during inspiration in supine and head-down tilt position has obvious similarity to those which hypothetically can be present in microgravity. The results suggest that intrathoracic hemodynamics during inspiration in supine and head-down position may be an adequate ground model for investigation of weightlessness influences on intrathoracic circulation. 相似文献
10.
This work deals with a comparative analysis of Stachybotrys chartarum strains isolated from various artificial cellulose-containing materials and natural substrates in geographically distant regions of Russia. The analysis included determination of the spore size; the strain toxicity to Paramecium caudatum; the strain resistance to the fungicides Benomil, Olilen, and Tilt; and the PCR study of the genome structure with the aid of a primer that was complementary to the core sequence of the SINE retrotransposon. It was found that some of the strains that were isolated from different areas and from different substrates differ in their toxicity, fungicide resistance, and genome structure. PCR analysis showed the absence of any correlation between the genome structure, the strain properties, the geographic area, and the substrates from which the strains were isolated. The pheno- and genotypic diversity of the strains and their different vegetative compatibility suggest the existence of an intraspecies diversity of the S. chartarum strains that were isolated in different geographic areas. The absence of any correlation between the pheno- and genotypic properties of the strains and the substrates from which they were isolated implies that the colonization of artificial substrates by S. chartarum occurred occasionally from natural habitats. The S. chartarum populations that live on artificial substrates are unlikely to have their own evolutionary history. 相似文献