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We report the effects of pine and oak litter on species composition and diversity of mycorrhizal fungi colonizing 2-year-old Pinus sylvestris L. seedlings grown in a bare-root nursery in Lithuania. A layer of pine or oak litter was placed on the surface of the nursery bed soil to mimic natural litter cover. Oak litter amendment appeared to be most favorable for seedling survival, with a 73% survival rate, in contrast to the untreated mineral bed soil (44%). The concentrations of total N, P, K, Ca, and Mg were higher in oak growth medium than in pine growth medium. Relative to the control (pH 6.1), the pH was lower in pine growth medium (5.8) and higher in oak growth medium (6.3). There were also twofold and threefold increases in the C content of growth medium with the addition of pine and oak litter, respectively. Among seven mycorrhizal morphotypes, eight different mycorrhizal taxa were identified: Suillus luteus, Suillus variegatus, Wilcoxina mikolae, a Tuber sp., a Tomentella sp., Cenococcum geophilum, Amphinema byssoides, and one unidentified ectomycorrhizal symbiont. Forest litter addition affected the relative abundance of mycorrhizal symbionts more than their overall representation. This was more pronounced for pine litter than for oak litter, with 40% and 25% increases in the abundance of suilloid mycorrhizae, respectively. Our findings provide preliminary evidence that changes in the supply of organic matter through litter manipulation may have far-reaching effects on the chemistry of soil, thus influencing the growth and survival of Scots pine seedlings and their mycorrhizal communities.  相似文献   
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We report the effects of pine and oak litter on species composition and diversity of mycorrhizal fungi colonizing 2-year-old Pinus sylvestris L. seedlings grown in a bare-root nursery in Lithuania. A layer of pine or oak litter was placed on the surface of the nursery bed soil to mimic natural litter cover. Oak litter amendment appeared to be most favorable for seedling survival, with a 73% survival rate, in contrast to the untreated mineral bed soil (44%). The concentrations of total N, P, K, Ca, and Mg were higher in oak growth medium than in pine growth medium. Relative to the control (pH 6.1), the pH was lower in pine growth medium (5.8) and higher in oak growth medium (6.3). There were also twofold and threefold increases in the C content of growth medium with the addition of pine and oak litter, respectively. Among seven mycorrhizal morphotypes, eight different mycorrhizal taxa were identified: Suillus luteus, Suillus variegatus, Wilcoxina mikolae, a Tuber sp., a Tomentella sp., Cenococcum geophilum, Amphinema byssoides, and one unidentified ectomycorrhizal symbiont. Forest litter addition affected the relative abundance of mycorrhizal symbionts more than their overall representation. This was more pronounced for pine litter than for oak litter, with 40% and 25% increases in the abundance of suilloid mycorrhizae, respectively. Our findings provide preliminary evidence that changes in the supply of organic matter through litter manipulation may have far-reaching effects on the chemistry of soil, thus influencing the growth and survival of Scots pine seedlings and their mycorrhizal communities.  相似文献   
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A study was made of the dependence of errors in recognizing visual and discriminating acoustic stimuli and of the reaction time (RT), on the duration of intersignal intervals (ISI) (10, 20, 50, 100, 200, 400, 600 and 1000 msec). With longer ISI a decrease in RT has been found, particularly pronounced in responses to the second stimuli of the pair. RT to the visual (acoustic) stimulus increases not only when an acoustic (photic) signal is present in the complex, but also in the case of its anticipation. The level of errors in recognizing visual and discriminating acoustic stimuli does not depend on ISI duration. The results so obtained are discussed as related to psychological refractory period and to interaction of sensorimotor channels of the human brain.  相似文献   
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As a result of immunological examination of 658 domestic ducks of 6 poultry farms and 269 doves caught in Vilnius, antiornithosis antibodies were revealed in 3.1 +/- 0.7% of ducks and in 36.4 +/- 2.9% of doves. They were also found in 20 of 34 wild waterfowl. The causative agent of ornithosis was isolated in virological examination of the organs of a coot. Ornithosis nature of an epizootic outbreak among ducks of a poultry farm was proved by virological examination. The population was examined immunologically (2285 persons) and by intradermal test with the ornithosis antigen (80 persons). Positive specific reactions were revealed in 32.6% of persons engaged in poultry tending, and in 7.6% of other rural population. A case of ornithosis in man engaged in fowling (of doves) for their examination is described.  相似文献   
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The influence of bovine serum albumin (BSA) on the formation of J-aggregates of meso-tetra(4-sulfonatophenyl)porphine (TPPS4) in aqueous acid solution (pH 1.3) has been investigated by means of absorption and fluorescence spectroscopy. TPPS4 concentration was kept constant at 2 microM while BSA concentration was varied to get TPPS4 : BSA molar ratios from 1 : 0.005 to 1 : 20. In the presence of protein at all used concentrations the intensity of J-aggregates absorption band was higher than that in the pure solution. Spectral changes indicated that the dynamic equilibrium of the aggregated TPPS4 species was highly dependent on the molar ratio between TPPS4 and BSA. Small relative concentrations of BSA (TPPS4 : BSA, 1 : 0.005-1 : 0.1) had a stimulating effect on formation of J-aggregates. Several fractions of J-aggregates located in protein and aqueous moieties were detected in mixed solutions at intermediate BSA concentrations (TPPS4 : BSA, 1 : 0.5-1 : 8), when the absorbance intensity of the J-aggregates was the highest. At the highest used BSA concentrations (TPPS4 : BSA, 1 : 10-1 : 20) the spectral properties of the remaining J-aggregates were similar to those typical for pure porphyrin solution. Additionally, the split of the Soret band into two with peaks at 440 nm and 423 nm was followed by the simultaneous appearance of Q bands and reflected the formation of TPPS4-BSA complexes including both protonated and deprotonated TPPS4 forms.  相似文献   
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The inflamed synovium of rheumatoid arthritis exhibits many features typical for neoplastic tissue implying that the photodynamic therapy might be an efficient modality for chronic poliarthritis. The accumulation of endogenously produced porphyrins after administration of exogenous 5-aminolevulinic acid (ALA) in a rabbit model of rheumatoid arthritis was evaluated by fluorescence spectroscopy. Independent of the way, intravenously or intra-articularly, in which ALA was administered to the experimental animals, the highest fluorescence intensity of endogenously produced porphyrins was detected in the tissues of the inflamed joints. Besides, the application of ALA had a systemic sensitising effect on the whole organism of rabbits. The highest amount of endogenously produced porphyrins in the inflamed joints measured from the surface of the skin above the synovium tissues was detected 1-3 h after the administration of ALA. Fluorescence measurements performed on the tissue specimens ex vivo showed the predominant accumulation of porphyrins in the synovium of the inflamed joints. The fluorescence of porphyrins was also observed in the cartilage tissues taken from knee joints. However, the fluorescence spectra features indicated that the composition of porphyrins detected in the cartilage tissues was different than that in the synovial tissues. The selective accumulation of porphyrins in the inflamed synovial tissues stands up for the application of photodynamic therapy in the treatment of rheumatoid arthritis and implies the possibility to use optical non-invasive methods based on fluorescence detection of endogenously produced porphyrins for diagnostics of inflamed tissues.  相似文献   
9.
The second-to-fourth digit ratio (2D:4D) is a sexually dimorphic somatic trait and has been proposed as a biomarker for the organizational, i.e., permanent, effects of prenatal testosterone on the human brain. Accordingly, recent research has related 2D:4D to a variety of sex-dependent, hormonally influenced traits and phenotypes. The geographical variation in typical 2D:4D is marked and presently poorly understood. This study presents the first investigation into the 2D:4D ratio in a Baltic country. A contemporary sample of 109 Lithuanian men and women was compared with data from a historical sample of 100 Lithuanian men and women, collected and published in the 1880s and rediscovered only now. The findings included the following lines of evidence: (i) seen in an international perspective, the average 2D:4D in Lithuania is low; (ii) there was a sex difference in 2D:4D in the expected direction in both samples; (iii) a previously adduced hypothesis of an association of lighter eye and hair color with higher, i.e., more feminized, 2D:4D received no support in both samples; and (iv) the average 2D:4D in the contemporary sample was higher than in the historical sample. In view of a hypothesized increase in 2D:4D in modern populations, owing to increased environmental levels of endocrine disruptors such as xenoestrogens, this latter finding appears to be of particular notice. However, because finger-length measurement methods differed across the samples, it cannot be safely ruled out that the apparent time trend in Lithuanian 2D:4D in truth is an artifact. The puzzling geographical pattern seen in the 2D:4D ratio and the question of possible time trends therein deserve further investigations.  相似文献   
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