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61.
Sakurai N Imai Y Masuda M Komatsubara S Tosa T 《Applied and environmental microbiology》1993,59(9):2857-2863
We have isolated mutants resistant to acidomycin, a biotin analog, from Serratia marcescens Sr41. Strain SB304, resistant to 0.5 mg of acidomycin (frequently called actithiazic acid) per ml, produced 5 mg of d-biotin per liter of a medium containing sucrose and urea. Strain SB412, which was isolated from SB304 on a minimal agar plate containing 2 mg of acidomycin per ml and 0.1 mg of 5-(2-thienyl)-valeric acid per ml, produced 20 mg of d-biotin per ml. The two enzymes related to biotin synthesis were found to be released from biotin-mediated feedback repression in these mutants. Transductional analysis revealed that SB412 had acquired at least two mutations, one in the biotin operon locus and the other in an unknown locus distant from the biotin operon locus. 相似文献
62.
We previously reported that an acidomycin-resistant mutant of Serratia marcescens Sr41, SB304, and a mutant that was derived from SB304 and was resistant to a higher concentration of acidomycin, SB412, produced 5 and 20 mg of D-biotin, respectively, per liter of a medium containing sucrose and urea (N. Sakurai, Y. Imai, M. Masuda, S. Komatsubara, and T. Tosa, Appl. Environ. Microbiol. 59:2857-2863, 1993). In order to increase the productivity of D-biotin, the biotin (bio) operons were cloned from strains SB412, SB304, and 8000 (wild-type strain), and pLGM412, pLGM304, and pLGW101, respectively, were obtained through subcloning. These plasmids harbored 7.2-kb DNA fragments coding for the bioABFCD genes on a low-copy-number vector and were introduced into SB304, SB412, and 8000. Among the resulting recombinant strains, SB412(pLGM304) exhibited the highest D-biotin production (200 mg/liter) in the production medium. The plasmid was stably maintained in cells. Unexpectedly, SB412(pLGM412) grew very slowly, and the D-biotin productivity of this recombinant strain was not evaluated because pLGM412 was unstable. 相似文献
63.
Noriyuki Suka Yoshinobu Shinohara Yasushi Saitoh Hisato Saitoh Kohei Ohtomo Masahiko Harata Edward Shpigelman Shigeki Mizuno 《Genetica》1993,88(2-3):93-105
About 65% of DNA in the chicken W chromosome has been shown to consist ofXhoI andEcoRI family repetitive sequences. These sequences showed remarkable delay in the electrophoretic mobility at low temperature
on a polyacrylamide gel. Three dimensional structures of the 0.7-kbXhoI and the 1.2-kbEcoRI family repeating units were estimated to be irregular solenoids using a computer program based on wedge angles of all the
16 dinucleotide steps. Fluorescencein situ hybridization demonstrated that these two family sequences were localized in a major heterochromatic body in an interphase
nucleus. Incorporation of bromodeoxyuridine into the W chromosome in the synchronous culture of MSB-1 cells occurred about
1 h later than the peak of S phase. The chromatin structure formed alongXhoI andEcoRI family sequences was suggested to be different from the total chromatin or chromatin containing the β-actin gene sequence
in that the linker DNA lengths of the former were significantly longer. Fractionation of theHaeIII-digested MSB-1 nuclei yielded a chromatin fraction in whichXhoI family sequences were partially enriched. Several DNA-binding proteins showing higher affinity for theXhoI family sequence were present in this fraction. 相似文献
64.
Koichi Ohshima Masahiro Kikuchi Shinichi Kobari Yuichi Masuda Fuyuki Eguchi Nobuhiro Kimura 《Virchows Archiv. B, Cell pathology including molecular pathology》1993,63(1):197-198
Using the polymerase chain reaction (PCR) to examine the occurrence ofbcl-2/JH joining produced by t(14;18) chromosomal translocation, amplified DNA was detected in 2 of 18 lymph nodes showing reactive
lymphadenopathy. The PCR was repeated in these two lymphs nodes using the same DNA samples, but no amplification was detected
at the second attempt. Thus the amplified DNA was considered to be derived from one copy of joinedbcl-2/JH in one cell, or from a few copies in a few clonal cells with the same joinedbcl-2/JH. These results suggest that false joining ofbcl-2/JH at the t(14;l8) junction may occur in reactive lymph nodes. 相似文献
65.
Kazuyoshi Masuda Shunji Nagata Koichiro Hirano Yasushi Takagishi Hidematsu Hirai 《Microbiology and immunology》1993,37(2):165-167
This paper describes an attempt to effectively induce antibody-dependent cell-mediated cytotoxicity (ADCC) in nude mice. A monoclonal antibody against α-fetoprotein, 80G, coadministered with spleen cells from other nude mice bearing HuH-7N (xenograft of human hepatoma cell line, HuH-7) significantly suppressed the growth of HuH-7N as compared to treatment with 80G alone. 80G with spleen cells from normal nude mice also had some suppressive effect. In contrast, no effect was observed with each spleen cells alone as well as 80G alone. These results suggest that further supply of effector cells could enhance ADCC activity in nude mice. 相似文献
66.
Kazuyoshi Masuda Shunji Nagata Koichiro Hirano Yasushi Takagishi Hidematsu Hirai 《生物化学与生物物理学报:疾病的分子基础》1993,1182(2):128-132
This study was carried out to clarify the reason for elevation of serum α-fetoprotein (AFP) level of nude mice bearing hepatoma cells after treatment with monoclonal antibodies (MoAbs) to AFP. MoAbs to AFP showed no effect on the cumulative amounts of AFP secreted from human hepatoma cell line, HuH-7, in vitro. However, the treatment of nude mice bearing HuH-7N cells (HuH-7 xenograft) with MoAbs to AFP led to elevation of the serum AFP level in spite of the fact that the growth curve of HuH-7N cells was similar to that for PBS treatment. This apparent elevation of the serum AFP level is thought to be due to the slow elimination of AFP-MoAb immune complexes with little lattice structure from circulation, but not the enhancement of AFP secretion of HuH-7N cells. Thus, when using a MoAb alone or MoAb-drug conjugate, the serum AFP level should only be cautiously used as a tumor marker for evaluating the targeting immunotherapy. 相似文献
67.
Akira Hikosaka Noriyuki Satoh Kazuhiro W. Makabe 《Development genes and evolution》1993,203(1-2):104-112
pHrMA4a-Z is a recombinant plasmid in which about 1.4 kb of the 5 flanking region of a gene for muscle actin HrMA4a from the ascidian Halocynthia roretzi is fused with the coding sequence of a bacterial gene for -galactosidase (lac-Z). In this study, we examined the expression of the fusion gene construct when it was introduced into eggs of another ascidian, namely Ciona savignyi. When a moderate amount of linearized pHrMA4a-Z was introduced into fertilized Ciona eggs, the expression of the reporter gene was evident in muscle cells of the larvae, suggesting that both species share a common machinery for the expression of muscle actin genes. The 5 upstream region of HrMA4a contains several consensus sequences, including a TATA box at -30, a CArG box at -116 and four E-boxes within a region of 200 bp. A deletion construct, in which only the 216-bp 5 flanking region of HrMA4a was fused with lac-Z, was expressed primarily in larval muscle cells. However, another deletion construct consisting of only the 61-bp upstream region of HrMA4a fused with lac-Z was not expressed at all. When pHrMA4a-Z or pHrMA4a-Z (–216) was injected into each of the muscle-precursor blastomeres of the 8-cell embryo, expression of the reporter gene was observed in larval muscle cells in a lineage-specific fashion. However, expression of the reporter gene was not observed when the plasmid was injected into non-muscle lineage. Therefore, the expression of the reporter gene may depend on some difference in cytoplasmic constituents between blastomeres of muscle and non-muscle lineage in the 8-cell embyo. 相似文献
68.
Sakaba Tomoka Soejima Akiko Fujii Shinji Ikeda Hajime Iwasaki Takaya Saito Hiroaki Suyama Yoshihisa Matsuo Ayumi Kozhevnikov Andrey E. Kozhevnikova Zoya V. Wang Hongfeng Wang Siqi Pak Jae-Hong Fujii Noriyuki 《Journal of plant research》2023,136(4):437-452
Journal of Plant Research - A group of temperate grassland plant species termed the “Mansen elements” occurs in Japan and is widely distributed in the grasslands of continental East... 相似文献
69.
Tan Kah-Siew; Hoson Takayuki; Masuda Yoshio; Kamisaka Seiichiro 《Plant & cell physiology》1992,33(2):103-108
Irradiation of white fluorescent light (5 W m2) inhibitedthe growth of Oryza coleoptiles. Light irradiation increasedstress-relaxation parameters of coleoptile cell walls, minimumstressrelaxationtime and relaxation rate, and decreased cellwall extensibility (strain/load). Under light conditions, thecontents of ferulic and diferulic acids ester-linked to thehemicellulosic arabinose residue in cell walls increased andcorrelated with the modification of the cell wall mechanicalproperties. These results suggest that light irradiation enhancesthe formation of diferulic acid bridges in hemicelluloses, makingcell walls mechanically rigid and thus inhibits cell elongationin rice coleoptiles. Also, irrespective of coleoptile age orthe presence of light, the ratio of diferulic acid to ferulicacid was almost constant, suggesting that the rate limitingstep in the formation of diferulic acid bridges in Oryza cellwalls is in the step of feruloylation. (Received September 24, 1991; Accepted December 3, 1991) 相似文献
70.
Noriko Takahashi Katsuyoshi Masuda Kenji Hiraki Kazuo Yoshihara Hung-Hsiang Huang Kay-Hooi Khoo Koichi Kato 《European journal of biochemistry》2003,270(12):2627-2632
To determine the glycoforms of squid rhodopsin, N-glycans were released by glycoamidase A digestion, reductively aminated with 2-aminopyridine, and then subjected to 2D HPLC analysis [Takahashi, N., Nakagawa, H., Fujikawa, K., Kawamura, Y. & Tomiya, N. (1995) Anal. Biochem.226, 139-146]. The major glycans of squid rhodopsin were shown to possess the alpha1-3 and alpha1-6 difucosylated innermost GlcNAc residue found in glycoproteins produced by insects and helminths. By combined use of 2D HPLC, electrospray ionization-mass spectrometry and permethylation and gas chromatography-electron ionization mass spectrometry analyses, it was revealed that most (85%) of the N-glycans exhibit the novel structure Manalpha1-6(Manalpha1-3)Manbeta1-4GlcNAcbeta1-4(Galbeta1-4Fucalpha1-6)(Fucalpha1-3)GlcNAc. 相似文献