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991.
Elham Sadeqzadeh Charles E. de Bock Maureen R. O’Donnell Anna Timofeeva Gordon F. Burns Rick F. Thorne 《FEBS letters》2014
The interaction between the Drosophila cadherins fat and dachsous is regulated by phosphorylation of their respective ectodomains, a process catalysed by the atypical kinase four-jointed. Given that many signalling functions are conserved between Drosophila and vertebrate Fat cadherins, we sought to determine whether ectodomain phosphorylation is conserved in FAT1 cadherin, and also whether FJX1, the vertebrate orthologue of four-jointed, was involved in such phosphorylation events. Potential Fj consensus phosphorylation motifs were identified in FAT1 and biochemical experiments revealed the presence of phosphoserine and phosphothreonine residues in its extracellular domain. However, silencing FJX1 did not influence the levels of FAT1 ectodomain phosphorylation, indicating that other mechanisms are likely responsible. 相似文献
992.
993.
Jianchang Zhou Paul C. Dimayuga Xiaoning Zhao Juliana YanoWai Man Lio Portia TrinidadTomoyuki Honjo Bojan CercekPrediman K. Shah Kuang-Yuh Chyu 《Biochemical and biophysical research communications》2014
Background
It is increasingly evident that CD8+ T cells are involved in atherosclerosis but the specific subtypes have yet to be defined. CD8+CD25+ T cells exert suppressive effects on immune signaling and modulate experimental autoimmune disorders but their role in atherosclerosis remains to be determined. The phenotype and functional role of CD8+CD25+ T cells in experimental atherosclerosis were investigated in this study.Methods and results
CD8+CD25+ T cells were observed in atherosclerotic plaques of apoE(−/−) mice fed hypercholesterolemic diet. Characterization by flow cytometric analysis and functional evaluation using a CFSE-based proliferation assays revealed a suppressive phenotype and function of splenic CD8+CD25+ T cells from apoE(−/−) mice. Depletion of CD8+CD25+ from total CD8+ T cells rendered higher cytolytic activity of the remaining CD8+CD25− T cells. Adoptive transfer of CD8+CD25+ T cells into apoE(−/−) mice suppressed the proliferation of splenic CD4+ T cells and significantly reduced atherosclerosis in recipient mice.Conclusions
Our study has identified an athero-protective role for CD8+CD25+ T cells in experimental atherosclerosis. 相似文献994.
995.
Lusheng Gu Yi Sheng Yan Chen Hao Chang Yongdeng Zhang Pingping Lv Wei Ji Tao Xu 《Biophysical journal》2014,106(11):2443-2449
Single molecule fitting-based superresolution microscopy achieves sub-diffraction-limit image resolution but suffers from a need for long acquisition times to gather enough molecules. Several methods have recently been developed that analyze high molecule density images but most are only applicable to two dimensions. In this study, we implemented a high-density superresolution localization algorithm based on compressed sensing and a biplane approach that provides three-dimensional information about molecules, achieving super-resolution imaging at higher molecule densities than those achieved using the conventional single molecule fitting method. 相似文献
996.
997.
998.
Magdalena A. Gutowska F. Melzner M. Langenbuch C. Bock G. Claireaux H. O. Pörtner 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(3):323-335
Acidification of ocean surface waters by anthropogenic carbon dioxide (CO2) emissions is a currently developing scenario that warrants a broadening of research foci in the study of acid–base physiology.
Recent studies working with environmentally relevant CO2 levels, indicate that some echinoderms and molluscs reduce metabolic rates, soft tissue growth and calcification during hypercapnic
exposure. In contrast to all prior invertebrate species studied so far, growth trials with the cuttlefish Sepia officinalis found no indication of reduced growth or calcification performance during long-term exposure to 0.6 kPa CO2. It is hypothesized that the differing sensitivities to elevated seawater pCO2 could be explained by taxa specific differences in acid–base regulatory capacity. In this study, we examined the acid–base
regulatory ability of S. officinalis in vivo, using a specially modified cannulation technique as well as 31P NMR spectroscopy. During acute exposure to 0.6 kPa CO2, S. officinalis rapidly increased its blood [HCO3
−] to 10.4 mM through active ion-transport processes, and partially compensated the hypercapnia induced respiratory acidosis.
A minor decrease in intracellular pH (pHi) and stable intracellular phosphagen levels indicated efficient pHi regulation. We conclude that S. officinalis is not only an efficient acid–base regulator, but is also able to do so without disturbing metabolic equilibria in characteristic
tissues or compromising aerobic capacities. The cuttlefish did not exhibit acute intolerance to hypercapnia that has been
hypothesized for more active cephalopod species (squid). Even though blood pH (pHe) remained 0.18 pH units below control values,
arterial O2 saturation was not compromised in S. officinalis because of the comparatively lower pH sensitivity of oxygen binding to its blood pigment. This raises questions concerning
the potentially broad range of sensitivity to changes in acid–base status amongst invertebrates, as well as to the underlying
mechanistic origins. Further studies are needed to better characterize the connection between acid–base status and animal
fitness in various marine species. 相似文献
999.
Meng Li Yiguo Hong Martin Gunter Klotz Ji-Dong Gu 《Applied microbiology and biotechnology》2010,86(2):781-790
Published polymerase chain reaction primer sets for detecting the genes encoding 16S rRNA gene and hydrazine oxidoreductase
(hzo) in anammox bacteria were compared by using the same coastal marine sediment samples. While four previously reported primer
sets developed to detect the 16S rRNA gene showed varying specificities between 12% and 77%, an optimized primer combination
resulted in up to 98% specificity, and the recovered anammox 16S rRNA gene sequences were >95% sequence identical to published
sequences from anammox bacteria in the Candidatus “Scalindua” group. Furthermore, four primer sets used in detecting the hzo gene of anammox bacteria were highly specific (up to 92%) and efficient, and the newly designed primer set in this study
amplified longer hzo gene segments suitable for phylogenetic analysis. The optimized primer set for the 16S rRNA gene and the newly designed primer
set for the hzo gene were successfully applied to identify anammox bacteria from marine sediments of aquaculture zone, coastal wetland, and
deep ocean where the three ecosystems form a gradient of anthropogenic impact. Results indicated a broad distribution of anammox
bacteria with high niche-specific community structure within each marine ecosystem. 相似文献
1000.
Man Deok Kim Minkyung Song Minho Jo Seung Gu Shin Jee Hyeong Khim Seokhwan Hwang 《Applied microbiology and biotechnology》2010,85(5):1611-1618
This paper reports the effects of changing pH (5–7) and temperature (T, 40–60 °C) on the efficiencies of bacterial hydrolysis of suspended organic matter (SOM) in wastewater from food waste recycling
(FWR) and the changes in the bacterial community responsible for this hydrolysis. Maximum hydrolysis efficiency (i.e., 50.5%
reduction of volatile suspended solids) was predicted to occur at pH 5.7 and T = 44.5 °C. Changes in short-chain volatile organic acid profiles and in acidogenic bacterial communities were investigated
under these conditions. Propionic and butyric acids concentrations increased rapidly during the first 2 days of incubation.
Several band sequences consistent with Clostridium spp. were detected using denaturing gel gradient electrophoresis. Clostridium thermopalmarium and Clostridium novyi seemed to contribute to butyric acid production during the first 1.5 days of acidification of FWR wastewater, and C. thermopalmarium was a major butyric acid producer afterward. C. novyi was an important propionic acid producer. These two species appear to be important contributors to hydrolysis of SOM in the
wastewater. Other acidogenic anaerobes, Aeromonas sharmana, Bacillus coagulans, and Pseudomonas plecoglossicida, were also indentified. 相似文献