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321.
Effects of climate change and management on net climate impacts of production and utilization of energy biomass in Norway spruce with stable age‐class distribution
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Piritta Torssonen Antti Kilpeläinen Harri Strandman Seppo Kellomäki Kirsti Jylhä Antti Asikainen Heli Peltola 《Global Change Biology Bioenergy》2016,8(2):419-427
We studied the effects of climate change and forest management scenarios on net climate impacts (radiative forcing) of production and utilization of energy biomass, in a Norway spruce forest area over an 80‐year simulation period in Finnish boreal conditions. A stable age‐class distribution was used in model‐based analyses to identify purely the management effects under the current and changing climate (SRES B1 and A2 scenarios). The radiative forcing was calculated based on an integrated use of forest ecosystem model simulations and a life cycle assessment (LCA) tool. In this work, forest‐based energy was used to substitute coal, and current forest management (baseline management) was used as a reference management. In alternative management scenarios, the stocking was maintained 20% higher in thinning compared to the baseline management, and nitrogen fertilization was applied. Intensity of energy biomass harvest (e.g. logging residues, coarse roots and stumps) was varied in the final felling of the stands at the age of 80 years. Also, the economic profitability (NPV, 3% interest rate) of integrated production of timber and energy biomass was calculated for each management scenario. Our results showed that compared to the baseline management, climate benefits could be increased by maintaining higher stocking in thinning over rotation, using nitrogen fertilization and harvesting logging residues, stumps and coarse roots in the final felling. Under the gradually changing climate (in both SRES B1 and A2), the climate benefits were lower compared to the current climate. Trade‐offs between NPV and net climate impacts also existed. 相似文献
322.
Kimmo I. Virtaneva Pavla Angelisová Thomas Baumruker Václav Hořejší Heli Nevanlinna Jim Schröder 《Immunogenetics》1993,37(6):461-465
CD37, CD53, and R2 leukocyte surface antigens are members of a novel family of structurally related proteins. They all have four transmembrane-spanning domains with a single major extracellular loop. The CD37 is expressed on B cells and on a sub-population of T cells. The CD53 is known as a panleukocyte marker. The R2 protein is an activation antigen of T cells. The CD37, CD53, and R2 genes were assigned with the help of human/rodent somatic cell hybrids and human-specific probes to human chromosomes 19, 1, and 11, respectively. For the regional assignment, various deletion hybrids were used to map CD37 to 19p13-q13.4, CD53 to 1p12-p31, and R2 to 11p12. 相似文献
323.
Metapopulation theory predicts that species richness and total population density of habitat specialists increase with increasing
area and regional connectivity of the habitat. To test these predictions, we examined the relative contributions of habitat
patch area, connectivity of the regional habitat network and local habitat quality to species richness and total density of
butterflies and day-active moths inhabiting semi-natural grasslands. We studied butterflies and moths in 48 replicate landscapes
situated in southwest Finland, including a focal patch and the surrounding network of other semi-natural grasslands within
a radius of 1.5 km from the focal patch. By applying the method of hierarchical partitioning, which can distinguish between
independent and joint contributions of individual explanatory variables, we observed that variables of the local habitat quality
(e.g. mean vegetation height and nectar plant abundance) generally showed the highest independent effect on species richness
and total density of butterflies and moths. Habitat area did not show a significant independent contribution to species richness
and total density of butterflies and moths. The effect of habitat connectivity was observed only for total density of the
declining butterflies and moths. These observations indicate that the local habitat quality is of foremost importance in explaining
variation in species richness and total density of butterflies and moths. In addition, declining butterflies and moths have
larger populations in well-connected networks of semi-natural grasslands. Our results suggest that, while it is crucial to
maintain high-quality habitats by management, with limited resources it would be appropriate to concentrate grassland management
and restoration to areas with well-connected grassland networks in which the declining species currently have their strongest
populations.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
324.
Chromosome malsegregation in binucleated lymphocytes is a useful endpoint to evaluate age effect on genetic stability. However, the investigations on chromosome malsegregation in binucleated lymphocytes from Chinese are scarce. In this study, peripheral blood lym- phocytes were collected from 14 old (60-70 years) and 10 young (22-26 years) healthy Chinese men. To detect malsegregation of the sex chromosomes, multi-color fluorescence in situ hybridization (FISH) was performed on binucleated lymphocytes, cytokinesis-blocked by cytochalasin B at the first mitosis after phytohaemagglutinin stimulation. Compared with that in young men, a significant increase in frequencies of loss of chromosome X (9.2± 3.2‰ vs. 1.1 ± 0.9‰, P 〈 0.001) and Y (2.5 ± 1.9‰ vs. 0.2± 0.3‰, P 〈 0.001) was found in old men. Similarly, nondisjunction of chromosome X (16.5± 3.4‰ vs. 3.5 ± 1.1‰, P 〈 0.001) and Y (7.2 ± 2.6‰ vs. 2.4 ± 1.3‰, P 〈 0.001) occurred more frequently in old men than in young men. Regardless of donor's age, nondisjunction is more prevalent than loss for both chromosome X and Y. The frequencies of observed simultaneous malsegregation were relatively higher than the expected, suggest- ing an association between malsegregation. These results indicated that in Chinese men, malsegregation of the sex chromosomes increases with age in an associated fashion, and nondisjunction accounts for the majority of spontaneous chromosome malsegregation. 相似文献
325.
Heikki Simola Jarmo J. Meriläinen Olavi Sandman Virpi Marttila Heli Karjalainen Minna Kukkonen Riitta Julkunen-Tiitto Johanna Hakulinen 《Hydrobiologia》1996,322(1-3):283-292
A routinely applicable palaeolimnological sampling and analysis programme for large lake monitoring was developed as part of the Lake Saimaa Biomonitoring Project (1990–1993). The scope of palaeolimnological analyses is to gain background information of the recent past (ca. 0–200 yr) of the lake ecosystem that is being monitored. We analyzed short sediment cores from three contrasting basins of the complex lake Saimaa in eastern Finland (nutrient-poor clearwater Lake Puruvesi; oligotrophic mesohumic Lake Paasivesi, and eutrophied and polluted mesohumic Lake Haukivesi). Each basin shows a unique developmental history under the various forms of human influence on the ecosystem. The following research approaches are evaluated in the study: echosounding, dating (210Pb varves, soot stratigraphy), element stratigraphies, biological remains (diatoms, cladocera, chironomids, sedimentary pigments). 相似文献
326.
Lees, J., Märss, T., Wilson, M. V. H., Saat, T. and ?pilev, H. 2011. The sculpture and morphology of postcranial dermal armor plates and associated bones in gasterosteiforms and syngnathiforms inhabiting Estonian coastal waters. ―Acta Zoologica (Stockholm) 93 : 422–435. Five fish species inhabiting Estonian coastal waters (Gasterosteus aculeatus L., Pungitius pungitius (L.), and Spinachia spinachia (L.) of the order Gasterosteiformes and Syngnathus typhle L. and Nerophis ophidion (L.) of the order Syngnathiformes) are described on the basis of the sculpture and morphology of their postcranial dermal armor plates, as revealed and illustrated by SEM images. This study shows that the shapes of these superficial skeletal elements vary by species as well as by their position on the body, whereas the sculpture on the bones is taxon specific. The detailed features allow the identification of isolated fossil and subfossil remains and show promise for future systematics studies. 相似文献
327.
Germination in Baltic coastal wetland meadows: similarities and differences between vegetation and seed bank 总被引:4,自引:0,他引:4
The abundance and variety of seedlings in Baltic coastal grasslands was studied in cattle grazed and ungrazed areas in seashore
and delta on the western coast of Finland. The vegetation, seed bank and environmental conditions of the same sites were also
studied. Altogether 4609 seedlings were observed in 79 field plots (20 cm× 20 cm) making an average of 1458.54 seedlings/m2. The majority of the seedlings were dicots (67.5%) and perennials (96.8%). Altogether 44 species and an average of 4.14 species
per plot were identified as seedlings. The most abundant taxon, Carex formed 23.2% of all the seedlings observed in the field. In the delta the seedling density was two times that found at the
seashore. Also, the numbers of species of seedlings per plot were significantly higher in the delta than in the seashore,
but in total, more species germinated from the seashore than from the delta even though the number of plots was higher in
the delta (n = 51) than in the seashore (n = 28). The numbers of species and seedlings per plot were smaller in grazed sites
than in ungrazed ones similar to the pattern earlier reported concerning the mature vegetation and seed bank. The mean numbers
of seedlings were the highest at lower geolittoral plots (about 20 cm elevation), where the seed bank was also densest. About
60.0% of the mature species in the plots were also detected as seedlings and 91.4% of the seedling species were found in the
mature vegetation of the plots. The number of seedlings was positively correlated with the cover of mature vegetation giving
support to the nurse effect theory. Seedling numbers were negatively correlated with the abundance of litter indicating that
litter restricts germination because it is a mechanical barrier but also decreases the amount of light. The number of seedlings
and species, both in total and per unit area, were greater in the seed bank than in the field seedling population. The seedling
population was more similar to the mature vegetation than to the seed bank.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
328.
One suggested anti‐predator function of alarm calls is to deliver a message to a predator that it has been detected. Moreover, giving the alarm call could provide a signal to the predator that capturing the individual giving the alarm is more difficult than capturing its silent group members, as the caller is probably the most aware of the predator's location. In an aviary experiment using stuffed dummy Willow Tits Poecile montanus, we assessed whether an authentic alarm call given by Willow Tit affected Pygmy Owl Glaucidium passerinum prey preference. In the experiment, the Owls attacked only the ‘silent’ dummy individuals, suggesting that alarm calling could offer direct fitness benefits to the caller by decreasing the attack risk of the caller relative to its group members. 相似文献
329.
Antti Kilpeläinen Heli Peltola Ismo Rouvinen Seppo Kellomäki 《Trees - Structure and Function》2006,20(1):16-27
The aim of this study was to analyse and model the effects of elevated temperature and carbon dioxide concentration on daily
height growth of 20-year-old Scots pines (Pinus sylvestris L.). The trees were grown with a low nitrogen supply in closed chambers with a factorial combination of two temperature regimes
(ambient and elevated) and two carbon dioxide concentrations (ambient and twice ambient). The temperature elevation corresponded
to the predicted increase at the site after a doubling in atmospheric CO2. The height growth of Scots pines was first empirically studied in terms of its onset, cessation and duration, and the allocation
of daily height growth within the growing period in 2000 and 2001, and then a model predicting daily height growth as a function
of daily temperature and temperature sum was developed. The empirical results showed elevated temperature to be the dominant
variable explaining variation in daily height growth. Elevated temperature also hastened both the onset and cessation of height
growth, and the temperature sums for both of them were higher in the elevated than in the ambient temperature treatments.
The daily variation in height growth could also be explained by the daily mean temperature in the model. Elevated CO2 concentration had no effect on the onset, cessation or duration of height growth. The amount of height growth was not affected
by any of the treatments. 相似文献
330.
Molecular and Cellular Biochemistry - Naringenin is a natural bioactive flavonoid with a wide spectrum of biological activities, including anti-carcinogenic ability. Our study aimed to investigate... 相似文献