全文获取类型
收费全文 | 156篇 |
免费 | 1篇 |
国内免费 | 1篇 |
出版年
2018年 | 2篇 |
2017年 | 3篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2014年 | 3篇 |
2013年 | 3篇 |
2012年 | 9篇 |
2011年 | 4篇 |
2010年 | 8篇 |
2009年 | 1篇 |
2008年 | 5篇 |
2007年 | 3篇 |
2006年 | 10篇 |
2005年 | 8篇 |
2004年 | 6篇 |
2003年 | 8篇 |
2002年 | 6篇 |
2001年 | 7篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1992年 | 5篇 |
1990年 | 1篇 |
1988年 | 2篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1970年 | 1篇 |
1966年 | 2篇 |
1954年 | 2篇 |
1952年 | 10篇 |
1951年 | 11篇 |
1950年 | 8篇 |
排序方式: 共有158条查询结果,搜索用时 125 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.
E E Dubinina L A Sal'nikova L F Efimova P A Evarestov 《Ukrainski? biokhimicheski? zhurnal》1986,58(3):31-36
The superoxide-dismutase (EC 1.15.1.1) activity was revealed in blood plasma after its successive treatment with alcohol, chloroform and one- or two-substituted phosphate. Its value is the highest when treating plasma with KH2PO4. The boiling of the supernatant liquid obtained after addition of K2HPO4 leads to a complete loss of the activity. The treatment of plasma with KH2PO4 provides higher stability of the enzyme to thermal actions. The analysis of EPR-spectra has shown the presence of different complex compounds of copper ions in the supernatant liquid. Certain experiments with the use of aqueous solutions of CuCl2 and histidine have shown that Cu2+ inhibits the superoxide-dismutase activity in samples treated with KH2PO4 and increases it in samples treated with K2HPO4. 相似文献
3.
4.
5.
P. D. Kim S. S. Zamay T. N. Zamay V. S. Prokopenko O. S. Kolovskaya G. S. Zamay V. Ya. Princ V. A. Seleznev A. I. Komonov E. A. Spivak R. Yu. Rudenko A. V. Dubinina A. V. Komarov V. V. Denisenko M. A. Komarova A. E. Sokolov A. A. Narodov V. P. Zjivaev A. S. Zamay 《Doklady. Biochemistry and biophysics》2016,466(1):66-69
Here we describe a method of forming large arrays (up to 109 pieces) of free magnetic Ni-nanodisks 50 nm thick coated on both sides with layers of 5 nm thick Au. The antitumor effect of the magnetic nickel gold-coated nanodisks and DNA aptamer conjugates was evaluated in vivo and in vitro. Under the influence of rotating magnetic field, the studied nanodisks can cause the death of Ehrlich ascites carcinoma cells. 相似文献
6.
Dubinina EE Gavrovskaya SV Kuzmich EV Leonova NV Morozova MG Kovrugina SV Smirnova TA 《Biochemistry. Biokhimii?a》2002,67(3):343-350
Specific features of metal-catalyzed oxidation (MCO) of purified proteins (human serum albumin and human erythrocyte superoxide dismutase) were analyzed by the oxidation level of tryptophan and tyrosine. The production of dityrosine cross-links and the oxidation of tryptophan residues were recorded by fluorescence. The degree of oxidative modification of the amino acid residues of the proteins depended on the concentration of the Fenton's medium components and on the incubation time. These changes were different in different proteins. By electrophoresis and gel-permeation chromatography, changes in the superoxide dismutase structure are shown to be caused by oxidative modification of the enzyme and to be accompanied by a decrease in its activity. Findings with OH. scavengers (mannitol and ethanol) suggest that oxidative modification of the proteins in Fenton's medium should be associated not only with hydroxyl radical but also with ferryl and perferryl ions and with the radical PH3. 相似文献
7.
It was established by hybridological analysis that winter bread wheat lines 1/74-91, 3/36-91, 5/55-91 possess single dominant gene of resistance to bunt (Tilletia caries (DC) Tul.), but lines 8/2-91, 5/43-91, 4/11-91 and 8/16-91 have two independent dominant genes for this character. These genes originated from Aegilops cylindrica are not identical to Bt1-Bt17 genes and are unknown to date. The lines were obtained from crosses between winter bread wheat variety Odeskaya polukarlikovaya and Aegilops cylindrica. 相似文献
8.
E. Yu. Chernousova V. N. Akimov E. V. Gridneva G. A. Dubinina M. Yu. Grabovich 《Microbiology》2010,79(5):672-678
Bacterial mats in sulfide aquatic systems of North Caucasus are basically composed by the species of genera Thiothrix and Sphaerotilus. Additionally, several non-filamentous sulfur-oxidizing bacteria were isolated from the mats and several minor 16S rRNA phylotypes were found in clone libraries from these mats. The minor components were affiliated with Proteobacteria, Chlorobia, Cyanobacteria and Firmicutes. Even in an individual mat population heterogeneity of Thiothrix spp. was revealed by analysis of 16S rRNA gene and RAPD-PCR. Five Thiothrix isolates were described as new species Thiothrix caldifontis sp. nov. and Thiothrix lacustris sp. nov. In the Thiothrix-Sphaerotilus type of bacterial mat the proportion of dominant organisms might be influenced by sulfide concentration in the spring water. The higher sulfide concentration (more than 10 mg/1) in the spring water is more favorable for the development of bacterial mats with dominant Thiothrix organisms than for Thiothrix-Sphaerotilus type of sulfur mat. 相似文献
9.
S. V. Klimov E. A. Burakhanova I. M. Dubinina G. P. Alieva E. B. Sal’nikova T. A. Suvorova O. G. Semenov 《Biology Bulletin》2007,34(4):340-345
We studied the influence of alien cytoplasm of spring goatgrass Aegilops ovata L. on some physiological parameters in winter wheat (Triticum aestivum L.), Mironovskaya 808, under normal conditions and in the case of modified source-sink relations. Measurements of relative rates of plant dry matter growth and its distribution among organs, CO2 exchange (photosynthesis upon light saturation and dark respiration), content of sugars (sucrose + glucose + fructose) and their ratio in leaves, frost hardiness, and indices of membrane stability and damage of leaves by frost have shown that, on average, alloplasmic hybrid differed from the initial cultivar by almost all parameters. Reduced frost hardiness, increased index of leaf damage by frost, lowered leaf content of sugars, and reduced sucrose/(glucose + fructose) ratio in the alloplasmic hybrid were combined with higher roots/leaves ratio, relative rate of dry matter growth, and photosynthesis and respiration rates. The alloplasmic hybrid was more tolerant to decreased source strength in source-sink relations as compared to the initial cultivar. 相似文献
10.
Abundance and structure of the communities of neutrophilic lithotrophic iron-oxidizing bacteria (FeOB) inhabiting four low-mineralized
ferruginous springs of the Marcial Waters Resort (South Karelia, Russia) and the brackish chalybeate spring of the Staraya
Russa Resort (Novgorod region, Russia), were investigated, as well as the physicochemical conditions of these environments.
In fresh iron-containing precipitates collected near the spring outlets and within the spring-discharge areas, as well as
along the spring watercourses, the numbers of unicellular FeOB enumerated on nutrient media ranged from 105 to 107 cells per 1 mL of sediments irrespective of the initial Fe(II) concentration (11–126 mg L−1). In the spring waters and along the spring watercourses inhabited by iron-oxidizing bacteria, the concentration of dissolved
oxygen did not exceed 0.05–0.1 mg L−1. Unicellular FeOB were predominant in three springs, while in the springs with relatively low Fe(II) concentrations (11–22
mg L−1), various morphological forms of Gallionella and uncultured forms of the iron-oxidizing bacterium Toxothrix trichogenes prevailed. In the model experiments with the water samples collected in the ferruginous springs and bogs under controlled
conditions, the fractionation of stable iron isotopes and the rate of iron oxidation were found to depend on the oxygen regime
and, to a lesser extent, on the initial Fe(II) concentration. The maximum enrichment of the iron oxides formed during the
simulation experiments with the light 54Fe isotope was observed during bacterial oxidation under microaerobic conditions at O2 concentrations of 0.1–0.3 mg L−1 and in the cultures of iron-oxidizing bacteria. During the abiogenic oxidation of Fe(II), the extent of stable isotope fractionation
was 1.5–2 times lower. Enrichment of Fe(III) oxides with the light 54Fe isotope (3- to 5-fold) was considerably lower at high rates of both the biogenic and abiogenic processes of iron oxidation
under aerobic conditions; however, it was more intense during the bacterial processes. Comparison of the rates of enrichment
of Fe(III) oxides with the light isotope during the model experiments with pure and enrichment cultures of iron-oxidizing
bacteria from the sediments of ferruginous springs and bogs revealed that the biogenic factor plays a key role in the oxidation
processes of the iron cycle, as well as in the differentiation of the composition of stable iron isotopes in the studied ecosystems. 相似文献