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791.
T Sugiyama A Kittaka H Takayama M Tomioka Y Ida R Kuroda 《Nucleic acids symposium series》2000,(44):41-42
We report the first example of chemical cross-linking of 5-formyl-2'-deoxyuridine containing oligonucleotides with oligopeptides through a Schiff base formation. Twenty amino acid residue peptides investigated here were derived from the DNA binding site of RecA protein. We have demonstrated that the lysine residue placed at the 6th or 8th position from the N-terminus of the peptide directly contacts with DNA. 相似文献
792.
BackgroundEvolutionarily homologous proteins bovine α-lactoalbumin (αLA) and hen egg-white lysozyme (HEL) are very similar in primary, secondary and tertiary structures involving the location of disulfide-bridges (S–S), and are resistant to the action of hydrolytic enzymes and reagents. It is of interest to examine and compare the difference in backbone cleavage characteristics, by using reductive and hydrolytic reagents.MethodsIn-source decay (ISD) combined with matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS), reductive treatment of αLA and HEL with dithiothreitol (DTT) and acid hydrolysis with trifluoroacetic acid (TFA) were employed to examine the difference in the backbone cleavage characteristics of αLA and HEL.ResultsThe treatment of αLA and HEL with DTT/AcOHNH3 resulted in similar cleavage behaviors of the backbone N-Cα and S–S bonds, i.e., the enhancements of the intensity and m/z range of sequence-reflected fragment ions were very similar. However, the treatment of αLA with DTT/TFA resulted in unexpected residue-specific degradation at the peptide bond of the Asp-Xxx, Xxx-Ser/Thr, Gln-Xxx, Xxx-Gly and Gly-Xxx residues, while HEL did not occur such degradation.ConclusionsThe results obtained above indicate that acidic αLA is very sensitive to acidic additive such as TFA, while basic HEL is resistance to acidic additives.General significanceThe study demonstrates the sensitive and resistant of evolutionary homologous proteins αLA and HEL to the acid hydrolysis and these characters come from acidic and basic nature of the proteins. 相似文献
793.
T Ishikawa S Takayama T Kitagawa 《Virchows Archiv. B, Cell pathology including molecular pathology》1978,28(3):235-242
Unscheduled DNA synthesis in highly differentiated ganglion cells of adult medaka (Oryzias latipes) was demonstrated by autoradiography. For this, part of bony skull of the fish was surgically removed and the brain of the living fish was directly exposed to a solution of 2 carcinogen and 3H-TdR. This technique is suitable for precise measurement of DNA repair synthesis in non-dividing cells of the central nervous system in vivo. Using this system, the effect of aging on the levels of DNA repair was investigated. There was no age-associated change in the ability of repair in ganglion cells of the medaka of various ages. 相似文献
794.
Naoya Takayama Alex Murison Shin-ichiro Takayanagi Christopher Arlidge Stanley Zhou Laura Garcia-Prat Michelle Chan-Seng-Yue Sasan Zandi Olga I. Gan Héléna Boutzen Kerstin B. Kaufmann Aaron Trotman-Grant Erwin Schoof Ken Kron Noelia Díaz John J.Y. Lee Tiago Medina Daniel D. De Carvalho Mathieu Lupien 《Cell Stem Cell》2021,28(3):488-501.e10
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795.
The conditions for rapid growth of Begonia plantlets from budsregenerated on leaf segments were studied, the ultimate aimbeing to develop a mass propagation procedure. Plantlet growthwas stimulated in submerged culture by Murashige-Skoog's mediumwith 10 or 30 g/liter sucrose, but was inhibited by a lower( x1/4) concentration of basal medium. Root development wassuperior in the lower strength medium. The greater amount ofsucrose, 30 g/liter, stimulated root growth more than the 10g/liter did. Buds required kinetin at a concentration of 0.3to 1 mg/liter, but did not require auxin. Plantlets reachedmaximum growth after 3 weeks of cultivation in 300-ml Erlenmeyerflasks containing 30 to 150 ml of medium that were shaken at180 rpm. Cultivation in jar and bubble column fermentors appearsto be advantageous for the large scale propagation of Begoniaplantlets. (Received December 8, 1980; Accepted February 4, 1981) 相似文献
796.
797.
PP19, a new placental tissue protein, has alpha 1-beta 1 electrophoretic mobility, a molecular weight of 36,500 and 3.9% carbohydrate. To study immunocytochemical PP19 localization in extravillous trophoblast, we obtained formalin-fixed specimens from extravillous tubal pregnancy at gestational weeks (GW) 7-9 (12 blocks); four early intrauterine pregnancies at GW 7-13 (12 blocks); four late pregnancies at GW 28-38 complicated with intramural uterine myoma, placenta increta and abruptio placenta (8 blocks); four invasive complete moles (9 blocks); and seven primary and metastatic gestational choriocarcinomas (12 blocks). Immunohistochemical staining was done for PP19, pregnancy-specific beta 1-glycoprotein (SP1) and human chorionic gonadotrophin (hCG) using the indirect-labeled antibody method [purified PP19 (Lot no. 225/242) and antibody against PP19 (Lot no. 632ZA) prepared by H. Bohn, antibodies against hCG (Behringwerke, Marburg, FRG) and SP1 (Dakopatts, Copenhagen, Denmark)]. In both early and late intrauterine pregnancies, the extravillous syncytiotrophoblastic cell (XST) showed positive staining for hCG and SP1 in the cytoplasm, as well as for PP19, which stained more intensively in the nucleus than in the cytoplasm. The three proteins were not seen in the evtravillous cytotrophoblastic cell (XCT) in the trophoblastic cell column and shell. The interstitial cytotrophoblast-like cell (ICT), which infiltrated into the decidua and myometrium, and their blood vessels, was immunoreactively positive for PP19 but negative for hCG and SP1 with the exception of SP1-positive ICT in the myometrium in late pregnancy. XST and ICT in the endosalpinx of tubal pregnancy stained for all three proteins.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
798.
S Horie T Watanabe Y Sone K Takayama H Ikeda N Takizawa 《Comparative biochemistry and physiology. B, Comparative biochemistry》1989,93(2):493-498
1. Strain variations among mice in terms of cytosolic DT-diaphorase activity were studied in liver, kidney, stomach and heart tissues with or without the administration of 3-tert-butyl-4-hydroxyanisole (BHA). 2. BHA induced DT-diaphorase activity in all strains examined, and the magnitude of induction varied depending on the strain and tissue. Among the 10 inbred strains tested, BALB/c and C57BL mice showed relatively large magnitudes of induction for liver DT-diaphorase, whereas C3H and CBA mice showed relatively small magnitudes. 3. Results of examinations of BALB/c-C3H-F1, -F2 and C57BL-CBA-F1 mice revealed that smaller magnitudes of induction of liver DT-diaphorase were inherited essentially as a dominant trait. The hereditary trait could be adequately explained by postulating two gene loci that regulate the magnitude of induction. 4. The possible significance of DT-diaphorase activity in chemical carcinogenesis was discussed. 相似文献
799.
B D Kabakoff N C Kendrick D Faber H F Deluca S Yamada H Takayama 《Archives of biochemistry and biophysics》1982,215(2):582-588
Oxygen-dependent calcium uptake by chick duodenal discs has been characterized and used to assay the relative activities of 1,25-dihydroxyvitamin D3 and its 24,24-difluoro analog. The calcium uptake was found to be stimulated by low sodium (30 mm) and phosphate (0.01–0.3 mm). The rate of oxygen-dependent calcium uptake was found half-maximal at a calcium concentration of 5 mm. At a concentration of 5 mm calcium, the uptake was linear for at least 15 min with approximately a threefold stimulation by prior administration of 1,25-dihydroxyvitamin D3 (125 ng). This determination, as well as increase in serum calcium and percentage bone ash, was used to assess the biological activities of 1,25-dihydroxyvitamin D3 and its 24,24-difluoro analog. The difluoro analog is about four to five times more active than 1,25-dihydroxyvitamin D3 as measured in each of these systems. 相似文献
800.
Japanese quail embryo (QE) cells were compared to chicken embryo (CE) cells with regard to the production of some group A arboviruses. The virus yield in QE cells was about the same as that in CE cells. The sensitivity of plaque assay of the viruses in QE cells was nearly equal to that in CE cells, although a certain range of fluctuation among individual culture bottles of QE cells was observed. QE cultures were found to possess some advantages for production and titration of group A arboviruses when compared CE cell system. 相似文献