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排序方式: 共有269条查询结果,搜索用时 15 毫秒
1.
In this paper the recent population changes of the Wild Boar in different European countries is analysed through the study of hunting statistics. A simultaneous increase in numbers is observed throughout the whole area during the period 1965–1975. From 1975 onwards the population stabilizes itself apart from in peripheral areas like Finland. Potentially favourable factors which play a part in this process are discussed and certain reproductive and dispersive characteristics which favour its invasive behaviour are discussed. 相似文献
2.
M A Grachev M I Dobrikov V D Knorre E K Pressman V V Roschke G V Shishkin 《FEBS letters》1983,162(2):266-269
Treatment of amino-group-containing antigens with adenosine-5'-trimetaphosphate results in their chemical modification by -pppA residues. An immunoanalytical system is proposed based upon competition of these ATP-labelled antigens with those of the sample for immobilized antibodies. Mild acidic treatment of complexes of ATP-labelled antigens with immobilized antibodies results in quantitative liberation of intact ATP. The latter may be determined by the ultrosenstive bioluminescent techniques based upon emission of light with firefly luciferase. The validity of the system has been studied with two clinically important antigens, thyroxine and myoglobin. 相似文献
3.
Authigenic mineralization and detrital clay binding by freshwater biofilms: The Brahmani river,India
Alexander Likhoshvay Tatiana Khanaeva Alexander Gorshkov Tamara Zemskaya Mikhail Grachev 《Geomicrobiology journal》2013,30(3):209-213
This study sought to understand the origin and fate of one of the bitumen mounds found on the bottom of Lake Baikal. These mounds are located at a depth of 900 m beneath oil spots detected on the surface of Lake Baikal (53° 18′24″, 108° 23′20″). The two mounds were sampled with a manipulator from a “MIR” deep-water manned submersible. Mature mound No. 8 was subjected to chemical and microbiological studies. Mound No. 3 was subjected only to chemical studies; we failed to perform microbiological analyses of this mound for logistic reasons. Oil spots collected from the water surface, samples of mound No. 3 and No. 8, were subjected to GC/MS analysis. The water contained aliphatic hydrocarbons with chains between C8 and C23, with the most abundant chain length being C18. Mound No. 3 with the most abundant chain length being C18 actively released oil droplets into the water. It contained 770 mg/g of C13-C32 n-alkanes, with a maximum at C23 (160 mg/g). Mound No. 8 was inactive and contained 148 mg/g of aliphatic C22-C34 n-alkanes, with a maximum at C25. Mound No. 8 also consisted of 3% inorganic matter, 48% unresolved complex mixture (UCM) and less than 1% other compounds (polyaromatic hydrocarbons, isoprenoids, carotenoids, and hopanes). The core of this sample used as inoculate, yielded Rhodococci when cultivated on oil as the only source of carbon. Cultivation of the sample on agar-containing Raymond inorganic medium with crude West Siberian oil as the only source of carbon revealed colonies of these bacteria, which all appeared identical. PCR was performed with DNA isolated from 5 colonies, using primers for 16S rRNA genes. Comparison of the sequences of the 5 PCR products over a length of 714 bp revealed that they were almost identical. Phylogenetic analysis of these homologous sequences showed that they were similar to the corresponding sequences of the genus Rhodococcus. Substrate demands, the morphology of the colonies, and SEM and TEM data confirmed that the isolates obtained could indeed be Rhodococci. All of the isolates could grow in bulk cultures with inorganic medium supplemented with crude oil. Moreover, all of the isolates degraded aliphatic hydrocarbons with lengths between C11 and C29. C23-C29 hydrocarbons were degraded completely. The isolates could grow at 4–37°C. The most unexpected finding was that of the many microorganisms capable of consuming oil, only Rhodococci exhibited this ability in the inactive bitumen mound. The possible mechanisms of how crude oil is transformed into bitumen mounds and mature bitumen are discussed. 相似文献
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5.
ANDRÉIA SILVA FLORES RÉA M. CORRÊA ELIANA R. FORNI-MARTINS ANA M. G. AZEVEDO TOZZI 《Botanical journal of the Linnean Society. Linnean Society of London》2006,151(2):271-277
Chromosome numbers were counted for 23 species of Crotalaria native to Brazil. Among these data there were new counts for 15 taxa, and some confirmed previous reports or represented numbers that were different from those cited previously. The chromosome numbers most frequently found were 2 n = 16 and 2 n = 32. Only C. incana L. had 2 n = 14 and C. tweediana Benth. had 2 n = 54. The counts 2 n = 32 and 54 were found in species of section Calycinae and 2 n = 16 and 14 in species of section Chrysocalycinae . The data revealed the importance of chromosomal parameters in the characterization of sections Calycinae and Chrysocalycinae in Brazil. We discuss the systematic significance and evolutionary aspects for the genus, comparing the results with the two sections that are native in Brazil. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 271–277. 相似文献
6.
V. A. Efimov A. V. Aralov S. A. Grachev O. G. Chakhmakhcheva 《Russian Journal of Bioorganic Chemistry》2010,36(5):628-633
An effective modification of the phosphotriester method has been developed for the automatic synthesis of DNA and RNA fragments
using O-nucleophilic intramolecular catalysis and the 2-(azidomethyl)benzoyl group for the protection of the amino groups of nucleotide
heterocyclic bases. 相似文献
7.
8.
S V Eliseeva V V Ivanitskaia S V Grachev E I Ivanov 《Biulleten' eksperimental'no? biologii i meditsiny》1990,110(9):318-321
The oxidative and phosphorylating functions of mitochondria (M) and their ultrastructure were studied in the myocardium of normal and 6.5-hour immobilized rats that belonged to different zoosocial groups. M from dominant rats under normal conditions were shown to exhibit higher energy and to possess better respiratory energy regulation than those of "outcast" rats. However, the ultrastructure of M had no group specificity in normal. The immobilization caused more profound changes in M from the dominant rats and led to a more pronounced swelling of M in the myocardium of the above rats than in the "outcast". M from the subdominant rats were most resistant to an immobilization stress. 相似文献
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10.
Vadim V. Annenkov Tatjana N. Basharina Elena N. Danilovtseva Mikhail A. Grachev 《Protoplasma》2013,250(5):1147-1155
We studied the growth of the araphid pennate diatom Synedra acus subsp. radians (Kützing) Skabichevskii using a fluorescent dye N 1,N 3-dimethyl-N 1-(7-nitro-2,1,3-benzoxadiazol-4-yl)propane-1,3-diamine (NBD-N2), which stains growing siliceous frustules but does not stain other subcellular organelles. We used a clonal culture of S. acus that was synchronized by silicon starvation. Epifluorescence microscopy was performed in two different ways with cells stained by the addition of silicic acid and the dye. Individual cells immobilized on glass were observed during the first 15–20 min following the replenishment of silicic acid after silicon starvation. Alternatively, we examined cells of a batch culture at time intervals during 36 h after the replenishment of silicic acid using fluorescence and confocal microscopy. The addition of silicic acid and NBD-N2 resulted in the rapid (1–2 min) formation of several dozen green fluorescent submicrometer particles (GFSPs) in the cytoplasm, which was accompanied by the accumulation of fluorescent silica inside silica deposition vesicles (SDVs) along their full length. In 5–15 min, GFSPs disappeared from the cytoplasm. Mature siliceous valves were formed within the SDVs during the subsequent 14–16 h. In the next 8–10 h, GFSPs appeared again in the cytoplasm of daughter cells. The data obtained confirm observations about the two-stage mechanism of silicon assimilation, which includes rapid silicon uptake (surge uptake) followed by slow silica deposition. It is likely that the observed GFSPs are silicon transport vesicles, which were first proposed by Schmid and Schulz in (Protoplasma 100:267–288, 1979). 相似文献