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921.
922.
Wei-Qiang Chen Anita Salmazo Matti Myllykoski Björn Sjöblom Martin Bidlingmaier Arnold Pollak Peter Baumgärtel Kristina Djinovic-Carugo Petri Kursula Gert Lubec 《Amino acids》2010,39(3):859-869
Most protein preparations require purification steps prior to biophysical analysis assessing protein stability, secondary
structure and degree of folding. It was, therefore, the aim of this study to develop a system to separate and purify a protein
from a commercially available medicinal product, recombinant human growth hormone (rhGH) and show preservation of conformation
and function following the gel-based procedure. The rhGH was run on clear native (CN) gels and recovered from the gels by
electroelution using D-Tube Dialyzer Midi under rigorous cooling. Melting point studies indicated preservation of the structural
integrity. This finding was confirmed by synchrotron radiation circular dichroism spectroscopy (SRCD) revealing an identical
folding pattern for the sample before and after electrophoretic separation and purification. Synchrotron small-angle X-ray
scattering (SAXS) indicated that the sample was folded and monomeric, both before and after separation and purification, and
that its shape corresponded well to the known crystal structure of GH. Binding properties of rhGH to a receptor-model system
before and after clear native electrophoresis were comparable. This analytical and preparative approach to purify and concentrate
a protein preserving conformation and function may be helpful for many applications in analytical, protein and stereochemistry. 相似文献
923.
924.
Anita C. Risch Sven Wirthner Matt D. Busse Deborah S. Page-Dumroese Martin Schütz 《Oecologia》2010,164(3):773-784
Interest in soil C storage and release has increased in recent years. In addition to factors such as climate/land-use change,
vertebrate animals can have a considerable impact on soil CO2 emissions. To date, most research has considered herbivores, while the impact of omnivorous animals has rarely been investigated.
Our goal was to determine how European wild boars (Sus scrofa L.), large omnivores that consume soil-inhabiting animals and belowground plant parts by grubbing in the soil, affect soil
C dynamics. We measured soil respiration (CO2), temperature, and moisture on paired grubbed and non-grubbed plots in six hardwood forest stands for a 3-year period and
sampled fine root and microbial biomass at the beginning and after 2 years of the study. We also measured the percentage of
freshly disturbed forest soil within the larger surroundings of each stand and used this information together with hunting
statistics and forest cover data to model the total amount of CO2 released from Swiss forest soils due to grubbing during 1 year. Soil CO2 emissions were significantly higher on grubbed compared to non-grubbed plots during the study. On average 23.1% more CO2 was released from these plots, which we associated with potential alterations in CO2 diffusion rates, incorporation of litter into the mineral soil and higher fine root/microbial biomass. Thus, wild boars considerably
increased the small-scale heterogeneity of soil properties. Roughly 1% of Switzerland’s surface area is similar to our sites
(boar density/forest cover). Given the range of forest soil disturbance of 27–54% at our sites, the geographic information
system model predicted that boar grubbing would lead to the release of an additional 49,731.10–98,454.74 t CO2 year−1. These values are relatively small compared to total soil emissions estimated for Swiss hardwood forests and suggest that
boars will have little effect on large-scale emissions unless their numbers increase and their range expands dramatically. 相似文献
925.
926.
Georgiana F. da Cruz Célio F. F. Angolini Luciana G. de Oliveira Patrícia F. Lopes Suzan P. de Vasconcellos Elaine Crespim Valéria M. de Oliveira Eugênio V. dos Santos Neto Anita J. Marsaioli 《Applied microbiology and biotechnology》2010,87(1):319-329
Microbial oxidation potentials of extremophiles recovered from Pampo Sul oil field, Campos Basin, Brazil, in pure culture
or in consortia, were investigated using high-throughput screening (HTS) and multibioreactions. Camphor (1), cis-jasmone (2), 2-methyl-cyclohexanone (3), 1,2-epoxyoctane (4), phenylethyl acetate (5), phenylethyl propionate (6), and phenylethyl octanoate (7) were used to perform multibioreaction assays. Eighty-two bacterial isolates were recovered from oil and formation water
samples and those presenting outstanding activities in HTS assays were identified by sequencing their 16S rRNA genes. These
results revealed that most microorganisms belonged to the genus Bacillus and presented alcohol dehydrogenase, monooxygenase, epoxide hydrolase, esterase, and lipase activities. 相似文献
927.
928.
929.
Fieke S Koopman Anita Beelen Karin H Gerrits Gijs Bleijenberg Tineke A Abma Marianne de Visser Frans Nollet 《BMC neurology》2010,10(1):8
Background
Postpoliomyelitis Syndrome (PPS) is a complex of late onset neuromuscular symptoms with new or increased muscle weakness and muscle fatigability as key symptoms. Main clinical complaints are severe fatigue, deterioration in functional abilities and health related quality of life. Rehabilitation management is the mainstay of treatment. Two different therapeutic interventions may be prescribed (1) exercise therapy or (2) cognitive behavioural therapy (CBT). However, the evidence on the effectiveness of both interventions is limited. The primary aim of the FACTS-2-PPS trial is to study the efficacy of exercise therapy and CBT for reducing fatigue and improving activities and quality of life in patients with PPS. Additionally, the working mechanisms, patients' and therapists' expectations of and experiences with both interventions and cost-effectiveness will be evaluated. 相似文献930.