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51.
52.
Jukka Bisi Tuija Liukkonen Sakari Mykrä Mari Pohja-Mykrä Sami Kurki 《European Journal of Wildlife Research》2010,56(5):771-779
This article focuses on the roots of the Finnish wolf conflict by using stakeholder evaluations of the wolf as a tool. The
recent growth of the wolf population has highlighted stakeholders’ contradictory objectives and revealed a conflict between
the two main stakeholders, conservationists and hunters, in wolf management. The question of hunting emerges as the core of
the conflict. The negative evaluation of the wolf by hunters reflects a competitive situation, which is typical of the historical
development of wolf management in Finland. In areas with the most abundant wolf populations, hunters view the wolf most negatively.
This study clearly demonstrates that the Finnish wolf conflict is rooted in the values of modern society and carries a long
historical, practical and ecological background in which humans and wolves compete over resources, mainly the moose. The conflict
between hunters and conservationists in wolf management is connected to the appreciation of moose as game and stems from competition
between humans and wolves over their prey and the historical presence or absence of the wolf. 相似文献
53.
Bojsen-Møller J Losnegard T Kemppainen J Viljanen T Kalliokoski KK Hallén J 《Journal of applied physiology (Bethesda, Md. : 1985)》2010,109(6):1895-1903
Due to the complexity of movement in cross-country skiing (XCS), the muscle activation patterns are not well elucidated. Previous studies have applied surface electromyography (SEMG); however, recent gains in three-dimensional (3D) imaging techniques such as positron emission tomography (PET) have rendered an alternative approach to investigate muscle activation. The purpose of the present study was to examine muscle use during double poling (DP) at two work intensities by use of PET. Eight male subjects performed two 20-min DP bouts on separate days. Work intensity was ~ 53 and 74% of peak oxygen uptake (Vo(2peak)), respectively. During exercise 188 ± 8 MBq of [(18)F]fluorodeoxyglucose ([(18)F]FDG) was injected, and subsequent to exercise a full-body PET scan was conducted. Regions of interest (ROI) were defined within 15 relevant muscles, and a glucose uptake index (GUI) was determined for all ROIs. The muscles that span the shoulder and elbow joints, the abdominal muscles, and hip flexors displayed the greatest GUI during DP. Glucose uptake did not increase significantly from low to high intensity in most upper body muscles; however, an increased GUI (P < 0.05) was seen for the knee flexor (27%) and extensor muscles (16%), and for abdominal muscles (21%). The present data confirm previous findings that muscles of the upper limb are the primary working muscles in DP. The present data further suggest that when exercise intensity increases, the muscles that span the lumbar spine, hip, and knee joints contribute increasingly. Finally, PET provides a promising alternative or supplement to existing methods to assess muscle activation in complex human movements. 相似文献
54.
Caroline PA de Haan Rauni I Kivistö Marjaana Hakkinen Jukka Corander Marja-Liisa Hänninen 《BMC microbiology》2010,10(1):200
Background
Campylobacter jejuni is the most common bacterial cause of human gastroenteritis worldwide. Due to the sporadic nature of infection, sources often remain unknown. Multilocus sequence typing (MLST) has been successfully applied to population genetics of Campylobacter jejuni and mathematical modelling can be applied to the sequence data. Here, we analysed the population structure of a total of 250 Finnish C. jejuni isolates from bovines, poultry meat and humans collected in 2003 using a combination of Bayesian clustering (BAPS software) and phylogenetic analysis. 相似文献55.
We introduce a Bayesian theoretical formulation of the statistical learning problem concerning the genetic structure of populations.
The two key concepts in our derivation are exchangeability in its various forms and random allocation models. Implications
of our results to empirical investigation of the population structure are discussed. 相似文献
56.
The Bayesian model-based approach to inferring hidden genetic population structures using multilocus molecular markers has become a popular tool within certain branches of biology. In particular, it has been shown that heterogeneous data arising from genetically dissimilar latent groups of individuals can be effectively modelled using an unsupervised classification formulation. However, most currently employed models ignore potential linkage within the employed molecular information, and can therefore lead to biased inferences under certain circumstances. Utilizing the general theory of graphical models, we develop a framework that accounts for dependences both within linked molecular marker loci and DNA sequence data. Due to a high level of sequence conservation among eukaryotic species, the latter aspect is particularly relevant for analyzing rapidly evolving microbial species. The advantages of incorporating the dependence due to linkage in the classification models are illustrated by analyses of both simulated data and real samples of Bacillus cereus. 相似文献
57.
Julkunen P Kiviranta P Wilson W Jurvelin JS Korhonen RK 《Journal of biomechanics》2007,40(8):1862-1870
Load-bearing characteristics of articular cartilage are impaired during tissue degeneration. Quantitative microscopy enables in vitro investigation of cartilage structure but determination of tissue functional properties necessitates experimental mechanical testing. The fibril-reinforced poroviscoelastic (FRPVE) model has been used successfully for estimation of cartilage mechanical properties. The model includes realistic collagen network architecture, as shown by microscopic imaging techniques. The aim of the present study was to investigate the relationships between the cartilage proteoglycan (PG) and collagen content as assessed by quantitative microscopic findings, and model-based mechanical parameters of the tissue. Site-specific variation of the collagen network moduli, PG matrix modulus and permeability was analyzed. Cylindrical cartilage samples (n=22) were harvested from various sites of the bovine knee and shoulder joints. Collagen orientation, as quantitated by polarized light microscopy, was incorporated into the finite-element model. Stepwise stress-relaxation experiments in unconfined compression were conducted for the samples, and sample-specific models were fitted to the experimental data in order to determine values of the model parameters. For comparison, Fourier transform infrared imaging and digital densitometry were used for the determination of collagen and PG content in the same samples, respectively. The initial and strain-dependent fibril network moduli as well as the initial permeability correlated significantly with the tissue collagen content. The equilibrium Young's modulus of the nonfibrillar matrix and the strain dependency of permeability were significantly associated with the tissue PG content. The present study demonstrates that modern quantitative microscopic methods in combination with the FRPVE model are feasible methods to characterize the structure-function relationships of articular cartilage. 相似文献
58.
Jakobsson E Jokilammi A Aalto J Ollikka P Lehtonen JV Hirvonen H Finne J 《The Biochemical journal》2007,405(3):465-472
Endosialidase (endo-N-acetylneuraminidase) is a tailspike enzyme of bacteriophages specific for human pathogenic Escherichia coli K1, which specifically recognizes and degrades polySia (polysialic acid). polySia is also a polysaccharide of the capsules of other meningitis- and sepsis-causing bacteria, and a post-translational modification of the NCAM (neural cell-adhesion molecule). We have cloned and sequenced three spontaneously mutated endosialidases of the PK1A bacteriophage and one of the PK1E bacteriophage which display lost or residual enzyme activity but retain the binding activity to polySia. Single to triple amino acid substitutions were identified, and back-mutation constructs indicated that single substitutions accounted for only partial reduction of enzymic activity. A homology-based structural model of endosialidase revealed that all substituted amino acid residues localize to the active site of the enzyme. The results reveal the importance of non-catalytic amino acid residues for the enzymatic activity. The results reveal the molecular background for the dissociation of the polySia binding and cleaving activities of endosialidase and for the evolvement of 'host range' mutants of E. coli K1 bacteriophages. 相似文献
59.
Varelius J 《Bioethics》2007,21(3):140-149
In a recent issue of this journal, David Silver and Gerald Dworkin discuss the physicians' role in execution by lethal injection. Dworkin concludes that discussion by stating that, at that point, he is unable to think of an acceptable set of moral principles to support the view that it is illegitimate for physicians to participate in execution by lethal injection that would not rule out certain other plausible moral judgements, namely that euthanasia is under certain conditions legitimate and that organ-donation surgery is sometimes permissible. This article draws attention to some problems in the views of Silver and Dworkin and suggests moral principles which support the three moral views just mentioned. 相似文献
60.
The effects of different land use types on nutrient and chemical run-off have been widely researched, but the total effect
of change in land use on the aquatic species community is not well-known. For this study we researched the effect of land
use change on the vascular plant communities in lakes. The study was conducted with aerial photographs and GIS-techniques
in the countryside of central Finland. We compared the change in vascular plant species community structure with the change
in land use around 25 lakes, between the years 1933–1934 and 1996. The change in land use was analyzed in two different riparian
zones. We found several indications of links between changes in land use and aquatic vascular plant species. According to
our data a decrease in agricultural land use, in particular fields and meadows, appears to influence species turnover and
increases the number of new vascular plant species. When the changes in fields and meadows were added together and compared
to the change in species turnover, the correlation was even more evident. Changes in land use types in a zone 0–100 m from
the lake shoreline correlated with a change in vascular plant species more often than changes in a larger, adjacent zone,
100–400 m from the shore. This indicates that changes in the few hundred meters nearest the lake have the most elemental consequences
for aquatic vascular plant species, giving an indication of the breadth of the protection zones needed between freshwaters
and agricultural lands. 相似文献