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951.
Kumar DA Settu K Raju KV Kumanan K Manohar BM Puvanakrishnan R 《Molecular and cellular biochemistry》2006,282(1-2):125-139
In this study, the effect of (Boc-Lys (Boc)-Arg-Asp-Ser (tBu)-OtBu), a tetrapeptide derivative (PEP1261) was examined for
antiproliferative potency and apoptotic induction. Synovial fibroblasts were isolated from collagen-induced arthritic (CIA)
rats and exposed to peptides viz., PEP1261, and parental peptides (KRDS and RGDS). Viability of the cells decreased in the
presence of PEP1261 at a lower concentration (0.1 mM) when compared to RGDS and KRDS (1 mM). The treatment of cells with peptides
showed induction of apoptosis, resulting in the cleavage of caspase-3 as well as its substrate poly-(ADP-ribose) polymerase
(PARP). Pretreatment of cells with caspase-3 inhibitor prevented inhibition of [3H] thymidine incorporation, DNA fragmentation, and cleavage of caspase-3 and PARP as confirmed by western blotting as well
as annexin-V/PI-staining using flow cytometry. However, caspase-1 and caspase-2 inhibitors did not prevent the peptides from
inducing apoptosis indicating that caspase-3 might have a role in the process of apoptosis induced by peptides. Treatment
of synovial fibroblasts with nitric oxide donor, S-nitroso-N-acetyl-dl-penicillamine (SNAP) (500 μM) showed significant elevation of nitric oxide levels and resulted in absence of apoptosis by
preventing the inhibition of [3H] thymidine incorporation. This was further evidenced by annexin V/propidium iodide (PI) staining and absence of DNA fragmentation,
intra cellular caspase-3 activity and PARP cleavage. In contrast, SNAP followed by PEP1261 and parental peptides-induced apoptosis
by lowering the levels of nitric oxide. These results suggested that PEP1261 suppressed the proliferation and induced apoptosis
in cultured synovial fibroblasts from CIA rats. This study also confirmed that PEP1261 inhibited nitric oxide level in cultured
synovial fibroblasts. 相似文献
952.
Jasmonic acid induced changes in protein pattern, antioxidative enzyme activities and peroxidase isozymes in peanut seedlings 总被引:1,自引:0,他引:1
G. J. Kumari A. M. Reddy S. T. Naik S. G. Kumar J. Prasanthi G. Sriranganayakulu P. C. Reddy Chinta Sudhakar 《Biologia Plantarum》2006,50(2):219-226
Protein pattern, ammonia content, glutamine synthetase activity, lipid peroxidation, superoxide dismutase, catalase, peroxidase
and peroxidase isoforms were studied in the leaves and roots of 7-d-old peanut (Arachis hypogaea L. cv. JL-24) seedlings treated by 25, 100 and 250 μM jasmonic acid (JA). SDS-PAGE protein profile of leaves and roots after
JA application showed a significant increase in 18, 21, 30, 45, 47 and 97.4 kDa proteins and significant decrease in 22 and
36 kDa proteins. Pathogenesis related PR-18 was specific in leaves at 250 μM JA and PR-21 have cross reacted differently with
21 and 30 kDa proteins in leaves and roots treated by all JA concentrations. Further, the immunoblot analysis with glutamine
synthetase, GS-45 antibodies revealed a specific cross reaction with 45 and 47 kDa proteins of both control and JA treated
leaves, however, higher at 100 and 250 μM JA treated leaves than control ones. Further, the malondialdehyde (MDA) content
significantly increased in leaves and roots treated with JA, indicated membrane damage with JA treatments that led to the
generation of peroxidation products. The peroxidase isozymic pattern showed two specific isoforms. Besides, the activities
of SOD and catalase were significantly elevated in JA treated leaves. 相似文献
953.
Koduru S Vegiraju SR Nadimpalli SK von Figura K Pohlmann R Dennes A 《Development genes and evolution》2006,216(3):133-143
Mannose-6-phosphate receptors (MPRs) have been identified in a wide range of species from humans to invertebrates such as
molluscs. A characteristic of all MPRs is their common property to recognize mannose-6-phosphate residues that are labelling
lysosomal enzymes and to mediate their targeting to lysosomes in mammalian cells by the corresponding receptor proteins. We
present here the analysis of full-length sequences for MPR 46 from zebrafish (Danio rerio) and its functional analysis. This is the first non-mammalian MPR 46 to be characterised. The amino acid sequences of the
zebrafish MPR 46 displays 70% similarity to the human MPR 46 protein. In particular, all essential cysteine residues, the
transmembrane domain as well as the cytoplasmic tail residues harbouring the signals for endocytosis and Golgi-localizing,
γ-ear-containing, ARF-binding protein (GGA)-mediated sorting at the trans-Golgi network, are highly conserved. The zebrafish
MPR 46 has the arginine residue known to be essential for mannose-6-phosphate binding and other additional characteristic
residues of the mannose-6-phosphate ligand-binding pocket. Like the mammalian MPR 46, zebrafish MPR 46 binds to the multimeric
mannose-6-phosphate ligand phosphomannan and can rescue the missorting of lysosomal enzymes in mammalian MPR-deficient cells.
The conserved C-terminal acidic dileucine motif (DxxLL) in the cytoplasmic domain of zebrafish MPR 46 essential for the interaction
of the GGAs with the receptor domains interacts with the human GGA1-VHS domain. Interestingly, the serine residue suggested
to regulate the interaction between the tail and the GGAs in a phosphorylation-dependent manner is substituted by a proline
residue in fish.
Electronic Supplementary Material Supplementary material is available for this article at .
The zebrafish MPR 46 sequence data have been submitted to the GenBank database under accession no. DQ089037. 相似文献
954.
Immunoaffinity purified Sm/RNP antigens from buffalo and goat liver were studied to determine the role of RNA and proteins
towards the antigenicity of Sm and RNP antigens. A more direct approach using enzyme-linked immunosorbent assay on nylon beads
has been utilized to look into the problem. The effect of enzyme treatment and the role of RNA and protein fractions in influencing
antigenicity have been described. RNA seems to be involved in the maintenance of RNP specific polypeptides in suitable conformation
so as to keep them in solution. Removal of RNA leads to insolubilization of RNP specific polypeptides. Antibodies to Sm and
RNP antigens have been shown to cross react with poly A containing heterogeneous nuclear ribonucleoprotein with no cross reactivity
with thymus RNA or DNA. 相似文献
955.
Sze Hang Fu Prabhat Jha Prakash C. Gupta Rajesh Kumar Rajesh Dikshit Dhirendra Sinha 《PloS one》2014,9(7)
Background
Tobacco smoking and binge alcohol drinking are two of the leading risk factors for premature mortality worldwide. In India, studies have examined the geographic distributions of tobacco smoking and alcohol drinking only at the state-level; sub-state variations and the spatial association between the two consumptions are poorly understood.Methodology
We used data from the Special Fertility and Mortality Survey conducted in 1998 to examine the geographic distributions of tobacco smoking and alcohol drinking at the district and postal code levels. We used kriging interpolation to generate smoking and drinking distributions at the postal code level. We also examined spatial autocorrelations and identified spatial clusters of high and low prevalence of smoking and drinking. Finally, we used bivariate analyses to examine the spatial correlations between smoking and drinking, and between cigarette and bidi smoking.Results
There was a high prevalence of any smoking in the central and northeastern states, and a high prevalence of any drinking in Himachal Pradesh, Arunachal Pradesh, and eastern Madhya Pradesh. Spatial clusters of early smoking (started smoking before age 20) were identified in the central states. Cigarette and bidi smoking showed distinctly different geographic patterns, with high levels of cigarette smoking in the northeastern states and high levels of bidi smoking in the central states. The geographic pattern of bidi smoking was similar to early smoking. Cigarette smoking was spatially associated with any drinking. Smoking prevalences in 1998 were correlated with prevalences in 2004 at the district level and 2010 at the state level.Conclusion
These results along with earlier evidence on the complementarities between tobacco smoking and alcohol drinking suggest that local public health action on smoking might also help to reduce alcohol consumption, and vice versa. Surveys that properly represent tobacco and alcohol consumptions at the district level are recommended. 相似文献956.
Rossi EJ Sim L Kuntz DA Hahn D Johnston BD Ghavami A Szczepina MG Kumar NS Sterchi EE Nichols BL Pinto BM Rose DR 《The FEBS journal》2006,273(12):2673-2683
Inhibitors targeting pancreatic alpha-amylase and intestinal alpha-glucosidases delay glucose production following digestion and are currently used in the treatment of Type II diabetes. Maltase-glucoamylase (MGA), a family 31 glycoside hydrolase, is an alpha-glucosidase anchored in the membrane of small intestinal epithelial cells responsible for the final step of mammalian starch digestion leading to the release of glucose. This paper reports the production and purification of active human recombinant MGA amino terminal catalytic domain (MGAnt) from two different eukaryotic cell culture systems. MGAnt overexpressed in Drosophila cells was of quality and quantity suitable for kinetic and inhibition studies as well as future structural studies. Inhibition of MGAnt was tested with a group of prospective alpha-glucosidase inhibitors modeled after salacinol, a naturally occurring alpha-glucosidase inhibitor, and acarbose, a currently prescribed antidiabetic agent. Four synthetic inhibitors that bind and inhibit MGAnt activity better than acarbose, and at comparable levels to salacinol, were found. The inhibitors are derivatives of salacinol that contain either a selenium atom in place of sulfur in the five-membered ring, or a longer polyhydroxylated, sulfated chain than salacinol. Six-membered ring derivatives of salacinol and compounds modeled after miglitol were much less effective as MGAnt inhibitors. These results provide information on the inhibitory profile of MGAnt that will guide the development of new compounds having antidiabetic activity. 相似文献
957.
High levels of genetic diversity are generated in Haemophilus influenzae populations through DNA repeat-mediated phase variation and recombination with DNA fragments acquired by uptake from the external milieu. Conversely, multiple pathways for maintenance of the genome sequence are encoded in H. influenzae genomes. In Escherichia coli, mutations in single-stranded-DNA exonucleases destabilise tandem DNA repeats whilst inactivation of recG can stabilise repeat tracts. These enzymes also have varying effects on recombination. Deletion mutations were constructed in H. influenzae genes encoding homologs of ExoI, RecJ and RecG whilst ExoVII was refractory to mutation. Inactivation of RecJ and RecG, but not ExoI, increased sensitivity to irradiation with ultraviolet light. An increase in spontaneous mutation rate was not observed in single mutants but only when both RecJ and ExoI were mutated. None of the single- or double-mutations increased or decreased the rates of slippage in tetranucleotide repeat tracts. Furthermore, the exonuclease mutants did not exhibit significant defects in horizontal gene transfer. We conclude that RecJ, ExoI and RecG are required for maintenance of the H. influenzae genome but none of these enzymes influence the generation of genetic diversity through mutations in the tetranucleotide repeat tracts of this species. 相似文献
958.
Gara SK Grumati P Urciuolo A Bonaldo P Kobbe B Koch M Paulsson M Wagener R 《The Journal of biological chemistry》2008,283(16):10658-10670
Here we describe three novel collagen VI chains, alpha4, alpha5, and alpha6. The corresponding genes are arranged in tandem on mouse chromosome 9. The new chains structurally resemble the collagen VI alpha3 chain. Each chain consists of seven von Willebrand factor A domains followed by a collagenous domain, two C-terminal von Willebrand factor A domains, and a unique domain. In addition, the collagen VI alpha4 chain carries a Kunitz domain at the C terminus, whereas the collagen VI alpha5 chain contains an additional von Willebrand factor A domain and a unique domain. The size of the collagenous domains and the position of the structurally important cysteine residues within these domains are identical between the collagen VI alpha3, alpha4, alpha5, and alpha6 chains. In mouse, the new chains are found in or close to basement membranes. Collagen VI alpha1 chain-deficient mice lack expression of the new collagen VI chains implicating that the new chains may substitute for the alpha3 chain, probably forming alpha1alpha2alpha4, alpha1alpha2alpha5, or alpha1alpha2alpha6 heterotrimers. Due to a large scale pericentric inversion, the human COL6A4 gene on chromosome 3 was broken into two pieces and became a non-processed pseudogene. Recently COL6A5 was linked to atopic dermatitis and designated COL29A1. The identification of novel collagen VI chains carries implications for the etiology of atopic dermatitis as well as Bethlem myopathy and Ullrich congenital muscular dystrophy. 相似文献
959.
Purification, immobilization and characterization of tannase from Penicillium variable 总被引:1,自引:0,他引:1
Tannase from Penicillium variable IARI 2031 was purified by a two-step purification strategy comprising of ultra-filtration using 100 kDa molecular weight cutoff and gel-filtration using Sephadex G-200. A purification fold of 135 with 91% yield of tannase was obtained. The enzyme has temperature and pH optima of 50 degrees C and 5 degrees C, respectively. However, the functional temperature range is from 25 to 80 degrees C and functional pH range is from 3.0 to 8.0. This tannase could successfully be immobilized on Amberlite IR where it retains about 85% of the initial catalytic activity even after ninth cycle of its use. Based on the Michaelis-Menten constant (Km) of tannase, tannic acid is the best substrate with Km of 32 mM and Vmax of 1.11 micromol ml(-1)min(-1). Tannase is inhibited by phenyl methyl sulphonyl fluoride (PMSF) and N-ethylmaleimide retaining only 28.1% and 19% residual activity indicating that this enzyme belongs to the class of serine hydrolases. Tannase in both crude and crude lyophilized forms is stable for one year retaining more than 60% residual activity. 相似文献
960.
OBJECTIVE: To compare 2 methods of fixation in bloody Pap smears with Carnoy's solution and 96% ethyl alcohol. STUDY DESIGN: After observation of contact bleeding, 2 samples were prepared from cervical cells with conventional Pap smear. One sample was fixed in 96% ethyl alcohol and another sample was fixed in Carnoy's solution. RESULTS: Of 450 slides, 410 were selected for study. In study of cell adequacy, diagnosis of squamous cells and glandular cells was better in Carnoy's-fixed slides. Blood contamination of slides was reduced in Carnoy's-fixed slides (13.85% vs. 49.51%), and clearance of slides was increased in Carnoy's-fixed slides. Diagnosis of inflammatory cells and pathogenic microorganisms in was increased in Carnoy's-fixed slides, but no difference was seen in diagnosis of epithelial cell and glandular cell abnormalities. CONCLUSION: Carnoy's solution can be used as an effective fixative in bloody smears in conventional Pap tests. 相似文献