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991.
992.
Objective
Olfaction is impaired in chronic rhinosinusitis (CRS). The study has two aims: (1) to determine whether changes in cation concentration occur in the olfactory mucus of mice with CRS, which may affect chemo-electrical transduction, (2) and to examine whether these alterations are physiologically significant in humans.Study Design
Animal study in mice and translational study in humans.Methods
Inflammation was induced by sensitization and chronic exposure of 16 C57BL/6 mice to Aspergillus fumigatus. The control group included 16 untreated mice. Ion-selective microelectrodes were used to measure free cation concentrations in the olfactory mucus of 8 mice from each treatment group, while the remaining mice were sacrificed for histology. To validate the findings in the animal model, olfactory threshold was measured in 11 healthy human participants using Sniffin’ Sticks before and after nasal irrigation with solutions that were composed of either of the cation concentrations.Results
In 8 mice, olfactory mucus of chronically inflamed mice had lower [Na+] (84.8±4.45 mM versus 93.73±3.06 mM, p = 0.02), and higher [K+] (7.2±0.65 mM versus 5.7±0.20 mM, p = 0.04) than controls. No difference existed in [Ca2+] (0.50±0.12 mM versus 0.54±0.06 mM, p = 0.39). In humans, rinsing with solutions replicating ion concentrations of the mouse mucosa with chronic inflammation caused a significant elevation in the median olfactory threshold (9.0 to 4.8, p = 0.003) but not with the control solution (8.3 to 7.8, p = 0.75).Conclusion
Chronic inflammation elevates potassium and lowers sodium ion concentration in mice olfactory mucus. Nasal irrigation with a corresponding solution induced olfactory threshold shift in humans. 相似文献993.
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996.
Impacts of cell surface characteristics on population dynamics in a sequencing batch yeast reactor treating vegetable oil-containing wastewater 总被引:1,自引:0,他引:1
Ten yeast strains acquired from different sources and capable of utilizing vegetable oil or related compounds (fatty acid
or oleic acid) as sole carbon sources were inoculated into a sequencing batch reactor (SBR) for the treatment of high-strength
vegetable oil-containing wastewater. The SBR system stably removed >89% of chemical oxygen demand (COD) and >99% of oil when
fed with wastewater containing 15 g/L COD and 10 g/L oil in average. Denaturing gradient gel electrophoresis of polymerase
chain reaction-amplified 26S rRNA genes showed that among the ten yeast strains, only Candida lipolytica, Candida tropicalis, and Candida halophila were dominant in the system. To elucidate the major factors affecting the selection of yeast strains in the SBR system, the
three dominant strains were compared with two non-dominant strains in terms of COD removal performance, biomass yield, cell
settleability, cell flocculation ability, cell emulsification ability, and surface hydrophobicity. Results showed that hydrophobicity
and emulsification ability of yeast cells were the two most important factors determining the selection of yeast strains in
the treatment of high-strength oil-containing wastewater. 相似文献
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998.
Chia-Hsuan Chen Hsiu-Lin Huang Mu-Tzu Chang Li-Chia Chiang Shih-Lin Cheng Bing-Tsan Liu Chih-Hua Wang Ming-Che Wu Mu-Chiou Huang 《Biologia》2011,66(6):1196-1201
The complete mitochondrial genome sequence of the Formosan sambar (Rusa unicolor swinhoei) was obtained by DNA sequencing based on PCR fragments amplified by 26 primer pairs designed by ourselves. The results indicated
that the mtDNA is 16,505 bp in size. This is the first report on mitochondrial DNA (mtDNA) sequence analysis of the Formosan
sambar and the sequence was deposited in the GenBank database under the accession number DQ989636. The complete mitochondrial
sequence included the following gene sequences: 12S and 16S rRNAs, 22 tRNAs and 13 protein-coding genes. The base composition
of the sequence was as follows: A, 33.51%; T, 28.97%; C, 24.07%; and G, 13.46%. The mitochondrial D-loop region was also analyzed
for comparative purposes in the Formosan sambar and 13 other species within the Cervidae family using neighbour-joining method.
The phylogenetic tree demonstrated that there are two separate groups, a European type and an Asian type, within the Cervidae
family. The D-loop sequences of mtDNA of 24 Formosan sambar animals were compared, and the results showed that the Formosan
sambar can be divided into two clades. 相似文献
999.
A new Mn(II) complex, [Mn2(edta)(H2O)]n·nH2O (1) (H4edta = ethylenediaminetetraacetic acid) has been synthesized by the reaction of MnCl2·4H2O and H4edta under hydrothermal conditions, and was characterized by single-crystal X-ray diffraction study, variable temperature (1.8-300 K) magnetic measurement, and thermal gravity analysis. The result of X-ray crystallographic analysis reveals that complex 1 is the first two-dimensional (2D) Mn-edta coordination polymer with a grid-like (4,4)-topology, which is built from Mn-carboxylate chains and entirely deprotonated edta4− ligands with a maximum denticity. The variable temperature magnetic data indicate that complex 1 exhibits strong antiferromagnetic couplings. 相似文献
1000.