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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.
A D Ado T A Lukmanova T A Alekseeva T A Avdeeva 《Biulleten' eksperimental'no? biologii i meditsiny》1977,84(11):590-593
Experimental pollinosis was modelled on guinea pigs. The animals were placed in a cell in which an allergen-water-dialyzed extract of ambrosia pollen was dispersed by means of coaxial pulveriser. Homocytotropic antibodies serving as indices of animal sensitization to the specific allergen formed in guinea pigs as a result of aerosol sensitization. Sensitization of the animals to the ambrosia allergen was accompanied by an increase of sensitivity of the broncho-pulmonary apparatus and was characterized by the bronchospastic reaction in resolving inhalation or inrtavenous injection of a specific allergen. 相似文献
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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
5.
Human Angiogenin Lacks Specific Antimicrobial Activity 总被引:1,自引:0,他引:1
Avdeeva SV Chernukha MU Shaginyan IA Tarantul VZ Naroditsky BS 《Current microbiology》2006,53(6):477-478
The antimicrobial activities of commercially available human angiogenin were studied against two pathogens, namely, Candida albicans and Streptococcus pneumoniae. In contrast to the data published earlier, antimicrobial action of angiogenin was rather limited and comparable to that of
bovine serum albumin. 相似文献
6.
Hrenovskoy pine forest is a unique island stand at the boundary of the species range of Scots pine Pinus sylvestris L. This object is of exceptional economic value, because it serves as a forest-seed base for the Voronezh oblast and some other regions of Russia; therefore, the stand and seed qualities have to be monitored constantly. The results of the first cytogenetic study of the seed progeny of P. sylvestris from the Morozov Grove, a high-quality stand in a reserved site within the Hrenovskoy pine forest, are reported. The studies have been performed in order to obtain a more correct assessment of seed quality based not only on their germination and energy of germination (traditionally used by forest breeders), but also on their genomic stability. The latter may be estimated by the stability of chromosome number in the somatic cells of seedlings and the regularity of mitotic divisions, because they also characterize the state of the generative system of parental forms and may serve as an integrated estimate of the stand development homeostasis. Therefore, the chromosome number, mitotic and nucleolar activities, and the number and spectrum of pathological mitoses (PMs) have been determined. Seedlings have been obtained from 240 seeds (collected from 12 trees) that resulted from free pollination. The cytological analysis of the rootlets of these seedlings has not detected any deviations from the chromosome number typical of the species P. sylvestris L. (2n = 24). However, considerable variation has been found in each family with respect to the mitotic index (MI) (from 4.2 +/- 0.36 to 8.1 +/- 0.39%) and the number of PMs (from 0.5 to 2.1%); micronuclei have also been found in each family (from 0.01 to 0.05%). In general, the phenotypic characteristics and the variation pattern of cytological parameters of the progeny of the trees studied in the Hrenovskoy pine forest, together with the high germination rate of seeds (90-98%), indicate that the current state of pines in the Hrenovskoy pine forest can be considered to be satisfactory. However, the presence of micronuclei in all variants and the decrease in MI in some individual plants (which was, on average, 6.1 +/- 0.03% in the sample studied, i.e., significantly lower than that of P. sylvestris from the Usmanskii pine forest (7.3 +/- 1.2%), where the conditions are optimal for this species) may serve as the bioindicators of the deterioration of both the state of trees themselves and the ecological conditions in the Hrenovskoy pine forest. Therefore, the population structure of this valuable autochtonic stand should be reproduced urgently. 相似文献
7.
TANATIN BI 《Mikrobiologiia》1951,20(6):506-511
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Y E Polotsky E M Dragunskaya V G Seliverstova T A Avdeeva M G Chakhutinskaya I Kétyi A Vertényl B Ralovich L Em?dy I Málovics N V Safonova E S Snigirevskaya E I Karyagina 《Acta microbiologica Academiae Scientiarum Hungaricae》1977,24(3):221-236
Macroscopic, light and electron microscopic alterations in ligated rabbit intestinal loops challenged with five standard enterotoxigenic Escherichia coli (ETEC) and twenty-three enteropathogenic E. coli (EEC-I) strains, freshly isolated from infantile enteritis cases, were investigated. Only two O26 : K60 : H11 strains produced enterotoxin. Their living cultures, sterile filtrates of the fluid medium and ultrasonic lysates of the bacteria resulted in pronounced hypersecretion of the intestinal epithelium followed by fluid accumulation and loop dilatation. These two E. coli strains, similarly as the other loop-negative EEC-I strains, were able to penetrate into the intestinal epithelium. In contrast to the standard ETEC strains, the EEC-I bacteria, adhering to the brush border, intruded into the microvilli, multiplied on the outer epithelial cell membrane making close contact with it and, causing, shedding of microvilli, penetrated into enterocytes becoming enclosed in membrane-bound phagosome-like vacuoles, appeared in the lamina propria and elicited mild focal polymorphonuclear infiltration. 相似文献
10.
For the aims of studying molecular mechanisms of functioning of adenylyl cyclase signaling systems (ACS), we investigated the influence of synthetic polycationic peptides of the star-like structure (dendrons), containing 48-60 sequence of HIV-1 TAT-protein, on the functional activity of ACS components in smooth muscles of the mollusc Anodonta cygnea and in rat skeletal muscles. It has been shown that the following peptides (Gly-Arg-Lys-Lys-Arg-Arg-Gln-Arg-Arg-Arg-Pro-Pro-Gln)2-Lys-epsilonAhx(= epsilon-aminohexanoic acid)-Cys(Acm), referred to as peptide I, (Gly-Arg-Gly-Asp-Ser-Gly-Arg-Lys-Lys-Arg-Arg-Gln-Arg-Arg-Arg-Pro-Pro-Gln)2-Lys-epsilonAhx-Cys(Acm) (peptide II), [(Gly-Arg-Lys-Lys-Arg-Arg-Gln-Arg-Arg-Arg-Pro-Pro-Gln)2-Lys-epsilonAhx-Cys]2 (peptide III), and [(Gly-Arg-Gly-Asp-Ser-Gly-Arg-Lys-Lys-Arg-Arg-Gln-Arg-Arg-Arg-Pro-Pro-Gln)2-Lys-epsilonAhx-Cys]2 (peptide IV) inhibit in a dose-dependent manner the adenylyl cyclase (AC) activity stimulated by both nonhormanal agents (GppNHp and forskolin) and hormones, such as serotonin (mollusc) and isoproterenol (rat). Peptides III and IV (tetrameric dendrons) were most effective in comparison with peptides I and II (dimeric dendrons). The AC activity stimulated by hormones and forskolin was most sensitive to the action of dendrons. All dendrons stimulated GTP-binding activity of G-proteins: dimeric dendrons were most effective at 10(-5) M concentration, whereas tetrameric dendrons at 10(-6) M. In the presence of dendrons, the affinity of beta-antagonist [3H]-dihydroalprenolol to P-adrenergic receptor in rat muscle mem- branes was unchanged. At the same time, the affinity of beta-agonist isoproterenol to the receptor decreased, and no shift to the right was observed on the curve of isoproterenol-induced [3H]-dihydroalprenolol displacement in the presence of GTP. The obtained data show the disturbance of the coupling between the receptor and G-protein, which is the main reason of dendron inhibitory action on AC stimulation by hormones. Besides, these data demonstrated that hormones could disturb the functional activity of AC, i.e. a catalytic component of ACS. 相似文献