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71.
The receptor for transferrin on murine myeloma cells: one-step purification based on its physiology, and partial amino acid sequence 总被引:3,自引:0,他引:3
I R van Driel P A Stearne B Grego R J Simpson J W Goding 《Journal of immunology (Baltimore, Md. : 1950)》1984,133(6):3220-3224
The receptor for transferrin is one of the major surface proteins of proliferating lymphocytes and other cells. It binds ferrotransferrin from serum and endocytoses it into an acidic nonlysosomal intracellular compartment where iron is released, but in which apotransferrin remains tightly bound to its receptor. Recycling of the apotransferrin-receptor complex to the cell surface is associated with a return to neutral pH and concomitant loss of affinity of apotransferrin for its receptor. Apotransferrin is then free to leave the cell and initiate a new cycle. We have exploited this cycle in a novel method for the purification of the receptor for transferrin. Murine myeloma cells were lysed in nonionic detergent, and the lysate passed over a column of ferrotransferrin-agarose at pH 7.4. After washing with sodium acetate at pH 5.0, iron was removed with sodium citrate pH 5.0 and desferrioxamine. Upon returning the pH to neutrality, the receptor was eluted and found to be homogeneous by SDS-polyacrylamide gel electrophoresis under both reducing and nonreducing conditions. The degree of purification was estimated to be at least 3,000-fold, and the calculated yield was 10 to 20%. The purified receptor was capable of binding to transferrin. The receptor was digested with trypsin, and the resulting peptides were separated by reversed-phase high performance liquid chromatography in NH4HCO3. Selected peptides were rechromatographed in 0.1% trifluoroacetic acid, and their amino acid sequences were determined. 相似文献
72.
73.
Helen M. Bailey R. D. J. Barker K. R. Libbenga P. C. G. van der Linde A. M. Mennes M. C. Elliott 《Biologia Plantarum》1985,27(2-3):105-109
A specific, high affinity, IAA binding site was demonstrated in both a cytosolic fraction, and in isolated nuclei, fromNicotiana tabacum cv. Wisconsin No. 38 cells grown in suspension culture. The amount of the binding site detected in both these fractions changed
during the culture cycle according to a strict pattern. The molecular mass of the binding site was estimated by gel filtration
to be approximately 175 000 and it appears to be a protein. When partially purified by affinity chromatography and allowed
to pre-incubate with IAA, the site had a significant stimulatory effect on total RNA synthesis, as measured by a cell-free
assay system. Unpurified extracts had no such effects. The system behaves rather like the steroid hormone-receptor system
in animals. 相似文献
74.
75.
Although mitral regurgitation (MR) is the most common valvular heart disease, it should be regarded as a complex multifactorial disease that involves 相似文献
76.
77.
A comparison of the respiratory chain in particles from Paracoccus denitrificans and bovine heart mitochondria by EPR spectroscopy 总被引:6,自引:0,他引:6
S P Albracht H W van Verseveld W R Hagen M L Kalkman 《Biochimica et biophysica acta》1980,593(2):173-186
A study is presented on the EPR characteristics of the paramagnetic groups in the respiratory chain present in membrane particles of Paracoccus denitrificans, the respiratory system of which is very similar to that in submitochondrial particles from beef heart. All paramagnetic prosthetic groups of the mitochondrial system are also found in the bacterial plasma membrane. Their properties suggest that the respiratory groups are embedded in very similar protein environments in the two systems. 相似文献
78.
79.
M. de Kwaadsteniet C. A. van Reenen L. M. T. Dicks 《Probiotics and antimicrobial proteins》2010,2(2):61-65
The potential of nisin F as an antimicrobial agent in treating subcutaneous skin infections was tested in vivo by infecting C57BL/6 mice with a bioluminescent strain of Staphylococcus aureus (Xen 36). Strain Xen 36 has the luxABCDE operon located on a native plasmid. Mice were grouped into four groups: Infected with strain Xen 36 and treated with nisin F, infected with strain Xen 36 and treated with saline (placebo), not infected and treated with nisin (control) and not infected and not treated (control). The immune systems of the mice were suppressed with deksamethasone. Mice were treated with either nisin F or sterile physiological saline 24 and 48 h after infection with subcutaneously injected S. aureus Xen 36 (4 × 106 CFU). Histology and bioluminescent flux measurements revealed no significant difference between infected mice treated with nisin and saline, respectively. However, infected mice treated with nisin F had an increased number of polymorphonuclear cells when compared with infected mice treated with saline. Also, not infected mice treated with nisin F had an influx of polymorphonuclear cells. Nisin F is thus ineffective in combating deep dermal staphylococcal infections. The apparent immune modulation of nisin when subcutaneously injected has to be investigated. 相似文献
80.
Maria D Mjaavatten Désirée van der Heijde Till Uhlig Anne J Haugen Halvor Nygaard Göran Sidenvall Knut Helgetveit Tore K Kvien 《Arthritis research & therapy》2010,12(3):R76