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101.
Two amphipods, the hypogean Niphargus stygius and epigean Gammarus fossarum, were analyzed for fatty acid (FA) composition, electron transport system (ETS) activity and respiration (R) during a laboratory
fasting experiment. In agreement with ETS and R measurements (and the ETS/R ratio), the hypogean N. stygius utilized FA more slowly than the epigean G. fossarum. Inter-specific differences in the utilization of certain FA during fasting were also revealed. While N. stygius tended to preserve all of its FA during the experimental fasting period, G. fossarum showed a tendency to utilize MUFA (monounsaturated FA) and SAFA (saturated FA) and preferentially retain PUFA (polyunsaturated
FA). The significant correlations between ETS activity and composition of specific FA during fasting can be linked to R. During
the fasting, both ETS activity and respiration rate of G. fossarum decreased, however, ETS/R ratio increased. In contrast, N. stygius did not show significant changes in these parameters. This is the first report, which connects ETS activity with changes
in concentrations of specific FA during fasting. Such evolutionary adaptations of hypogean species enables them to better
survive chronically low and/or discontinuous food supplies compared to epigean species, which live in environments where food
shortages are much less frequent. 相似文献
102.
Raspor Martin Motyka Václav Ninković Slavica Malbeck Jiří Dobrev Petre I. Zdravković-Korać Snežana Simonović Ana Ćosić Tatjana Cingel Aleksandar Savić Jelena Zahajská Lenka Tadić Vojin Dragićević Ivana Č. 《Journal of Plant Growth Regulation》2021,40(1):37-47
Journal of Plant Growth Regulation - Over the last years, cytokinin deficiency has been studied in a variety of plant species, using transgenic expression of cytokinin oxidase/dehydrogenase genes... 相似文献
103.
104.
Darja Duh Mirko Slovák Ana Saksida Katja Strašek Miroslav Petrovec Tatjana Avšič-Županc 《Biologia》2006,61(2):231-233
Dermacentor reticulatus ticks are recognized as the most important vectors of Babesia canis, the aetiological agent of canine babesiosis occurring throughout Europe. Vector competence of D. reticulatus for B. canis is well described and experimentally determined; however, by using molecular analysis it was proven so by one recent study
in Russia. Herein, the additional molecular evidence of B. canis infection in D. reticulatus ticks collected in Slovakia is provided. Using PCR followed by sequencing of distinctive amplicons we determined the presence
of Babesia canis canis in one of 100 tested adult ticks. Two zoonotic pathogens, Francisella tularensis and Coxiella burnetii, were previously isolated from D. reticulatus ticks in Slovakia. In our samples, we detected only the presence of F. tularensis. 相似文献
105.
W E Müller P Reuter Y Kuchino J van Rooyen H C Schr?der 《European journal of biochemistry》1989,183(2):391-396
Previously it was established [Pahwa, S., Pahwa, R., Saxinger, C., Gallo, R. C. & Good, R. A. (1985) Proc. Natl. Acad. Sci. USA 82, 8198] that nonviable preparations of human immunodeficiency virus 1 (HIV-1) abolish the proliferative response of human lymphocytes to phytohemagglutinin A. Now we describe that this effect might be, at least partially, due to an impairment of the function of phospholipase C. It was found that addition of HIV-1 preparation to lymphocytes diminished the stimulation of phosphatidylinositol phosphorylation caused by phytohemagglutinin A. Moreover, this preparation completely abolished the phytohemagglutinin-A-stimulated release of inositol trisphosphate and prevented a translocation of protein kinase C from cytosol to membranes. From this data we conclude that nonviable HIV-1 preparations inhibit the intracellular signalling pathway, leading to a reduced mitogenic response to phytohemagglutinin A, at the level of protein kinase C. 相似文献
106.
David Wragg Elizabeth A. J. Cook Perle Latr de Lat Tatjana Sitt Johanneke D. Hemmink Maurine C. Chepkwony Regina Njeru E. Jane Poole Jessica Powell Edith A. Paxton Rebecca Callaby Andrea Talenti Antoinette A. Miyunga Gideon Ndambuki Stephen Mwaura Harriet Auty Oswald Matika Musa Hassan Karen Marshall Timothy Connelley Liam J. Morrison B. Mark deC. Bronsvoort W. Ivan Morrison Philip G. Toye James G. D. Prendergast 《PLoS genetics》2022,18(4)
East Coast fever, a tick-borne cattle disease caused by the Theileria parva parasite, is among the biggest natural killers of cattle in East Africa, leading to over 1 million deaths annually. Here we report on the genetic analysis of a cohort of Bos indicus (Boran) cattle demonstrating heritable tolerance to infection with T. parva (h2 = 0.65, s.e. 0.57). Through a linkage analysis we identify a 6 Mb genomic region on bovine chromosome 15 that is significantly associated with survival outcome following T. parva exposure. Testing this locus in an independent cohort of animals replicates this association with survival following T. parva infection. A stop gained variant in a paralogue of the FAF1 gene in this region was found to be highly associated with survival across both related and unrelated animals, with only one of the 20 homozygote carriers (T/T) of this change succumbing to the disease in contrast to 44 out of 97 animals homozygote for the reference allele (C/C). Consequently, we present a genetic locus linked to tolerance of one of Africa’s most important cattle diseases, raising the promise of marker-assisted selection for cattle that are less susceptible to infection by T. parva. 相似文献
107.
Saleta Sierra J. Nikolai Dybowski Alejandro Pironti Dominik Heider Lisa Güney Alex Thielen Stefan Reuter Stefan Esser Gerd F?tkenheuer Thomas Lengauer Daniel Hoffmann Herbert Pfister Bj?rn Jensen Rolf Kaiser 《PloS one》2015,10(5)
ObjectivesWe analysed the impact of different parameters on genotypic tropism testing related to clinical outcome prediction in 108 patients on maraviroc (MVC) treatment.Methods87 RNA and 60 DNA samples were used. The viral tropism was predicted using the geno2pheno[coreceptor] and T-CUP tools with FPR cut-offs ranging from 1%-20%. Additionally, 27 RNA and 28 DNA samples were analysed in triplicate, 43 samples with the ESTA assay and 45 with next-generation sequencing. The influence of the genotypic susceptibility score (GSS) and 16 MVC-resistance mutations on clinical outcome was also studied.ResultsConcordance between single-amplification testing compared to ESTA and to NGS was in the order of 80%. Concordance with NGS was higher at lower FPR cut-offs. Detection of baseline R5 viruses in RNA and DNA samples by all methods significantly correlated with treatment success, even with FPR cut-offs of 3.75%-7.5%. Triple amplification did not improve the prediction value but reduced the number of patients eligible for MVC. No influence of the GSS or MVC-resistance mutations but adherence to treatment, on the clinical outcome was detected.ConclusionsProviral DNA is valid to select candidates for MVC treatment. FPR cut-offs of 5%-7.5% and single amplification from RNA or DNA would assure a safe administration of MVC without excluding many patients who could benefit from this drug. In addition, the new prediction system T-CUP produced reliable results. 相似文献
108.
109.
Gernot Grangl Evelyn Z?hrer Martin K?stenberger Alexandra Jud Günter Fauler Hubert Scharnagl Tatjana Stojakovic Robert Marterer Andreas Gamillscheg J?rg Jahnel 《PloS one》2015,10(12)
Background and Aims
Patients with repaired tetralogy of Fallot may develop chronic right ventricular dysfunction and hepatic congestion over time. We hypothesized that bile acid metabolism is altered in repaired tetralogy of Fallot patients and therefore sought to correlate right ventricular indices with serum bile acid levels.Methods
Indexed right ventricular end diastolic volume, as assessed by cardiac magnetic-resonance imaging, was classified as <100ml/m2 (Group 1, n = 5), 100–150ml/m2 (Group 2, n = 18), and >150ml/m2 (Group 3, n = 6) in 29 patients with repaired tetralogy of Fallot. Pulmonary regurgitation fraction and right ventricular ejection fraction were calculated. The serum bile acid profile, including 15 species, in these patients was determined by liquid chromatography coupled with mass spectrometry.Results
Serum bile acid levels increased from Group 1 to Group 3 (2.5 ± 0.7; 4.1 ± 2.5; 6.0 ± 2.8 μmol/l, respectively) with significantly increased bile acid values in Group 3 compared to Group 1 (p≤0.05). In Group 3, but not in Group 1 and 2, a significant increase in glycine-conjugated bile acids was observed. Pulmonary regurgitation fraction increased (12 ± 1; 28 ± 16; 43 ± 3%, Groups 1–3, respectively) and right ventricular ejection fraction decreased (48.4 ± 6.4; 48.5 ± 6.5; 42.1 ± 5.3%, Groups 1–3, respectively) with rising indexed right ventricular end diastolic volume.Conclusions
These preliminary results suggest that serum bile acid levels are positively correlated with indexed right ventricular end-diastolic volume in patients with repaired tetralogy of Fallot; however, this needs to be confirmed in a larger patient cohort. 相似文献110.
Respiratory electron transport system (ETS) activity and oxygen consumption in the interstitial water, and in the fine (i.e.
silt) and coarse (sand) sediment fractions from the hyporheic zone of the prealpine river Bača (W Slovenia) have been measured
in order to estimate the intensity of potential and actual carbon mineralization through microbial communities. Hyporheic
samples from the river bed (RB) and gravel bars (GB) were compared. ETS activity and oxygen consumption of all fractions from
the RB did not differ significantly from those from the GB. ETS activity and oxygen consumption of biofilm attached to 1 g
of the silt were higher than of that attached to the same mass of the sand. A significant correlation between ETS activity
and oxygen consumption indicated that the former should be a good indicator of intensity of bioactivity in hyporheic sediments.
The ratio of ETS activity to oxygen consumption (ETS/R ratio) revealed that the oxygen consumption of microorganisms is responsible
for approximately 60% of the metabolic potential in the hyporheic sediments. The contributions of different fractions of sediment
to the total ETS activity differed between RB and GB. The contribution of microorganisms in the interstitial water and silt
was higher in GB than in the RB, but the sand fraction contributed less to potential carbon loss in GB than in the RB. Average
total respiratory carbon loss per volume through the hyporheic zone was higher in the RB than in GB. The main reasons suggested
are the different intensity of exchange of surface water with the hyporheic zone, and the rate of consolidation of sediments,
which is primarily a function of river hydrology and geomorphology.
Handling editor: J. Padisak 相似文献