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951.
Hideo Fujimoto Alauddin Ahmed Yasuhiro Iida Mineo Hanai 《Flexible Services and Manufacturing Journal》2003,15(4):283-307
This paper comprehensively studies assembly process design (APD) to handle variety and presents a new approach to strategically manage manufacturing complexities because of product varieties. It links the chronological steps of APD to a general approach with a view to reduce both short and long term wastes. It synthesizes two strategic approaches, product and process-based, while exploiting the APD of an entire product family. A new evaluation method for measuring the complexities of an assembly system at different stages of design has been introduced by applying information entropy. The developed evaluation methodology explains the available techniques related to design, interprets them from a design for variety point of view, and leads to techniques to manage complexities in manufacturing. The suggested methodology has been applied to examples from automobile part manufacturers and has been found to be effective in understanding the complexities in manufacturing and leading to some strategies to manage variety. 相似文献
952.
Takashi Maruoka Yurika Nagasoe Shinobu Inoue Yasunori Mori June Goto Mitsunobu Ikeda Hidetoshi Iida 《The Journal of biological chemistry》2002,277(14):11645-11652
The yeast Saccharomyces cerevisiae MID1 gene encodes a stretch-activated Ca(2+)-permeable nonselective cation channel composed of 548 amino acid residues. A physiological role of the Mid1 channel is known to maintain the viability of yeast cells exposed to mating pheromone, but its structural basis remains to be clarified. To solve this problem, we identified the mutation sites of mid1 mutant alleles generated by in vivo ethyl methanesulfonate mutagenesis and found that two mid1 alleles have nonsense mutations at the codon for Trp(441), generating a truncated Mid1 protein lacking two-thirds of the intracellular carboxyl-terminal region from Asn(389) to Thr(548). In vitro random mutagenesis with hydroxylamine also showed that the carboxyl-terminal region is essential. To identify the functional portion of the carboxyl-terminal region in detail, we performed a progressive carboxyl-terminal truncation followed by functional analyses and found that the truncated protein produced from the mid1 allele bearing the amber mutation at the codon for Phe(522) (F522Am) complemented the mating pheromone-induced death phenotype of the mid1 mutant and increased its Ca(2+) uptake activity to a wild-type level, whereas N521Am did not. This result indicates that the carboxyl-terminal domain spanning from Asn(389) to Asn(521) is required for Mid1 function. Interestingly, this domain is cysteine-rich, and alanine-scanning mutagenesis revealed that seven out of 10 cysteine residues are unexchangeable. These results clearly indicate that the carboxyl-terminal domain including the cysteine residues is important for Mid1 function. 相似文献
953.
954.
H Kamiya N Murata-Kamiya E Iida H Harashima 《Biochemical and biophysical research communications》2001,288(3):499-502
To examine the possibility that the Orf135 protein of Escherichia coli functions as a hydrolyzing enzyme for a damaged DNA precursor (deoxyribonucleoside 5'-triphosphate), we purified the recombinant Orf135 protein and incubated it with oxidized deoxynucleotides. Of the nucleotides tested, 2-hydroxydeoxyadenosine 5'-triphosphate, and somewhat less efficiently, 8-hydroxydeoxyguanosine 5'-triphosphate, were hydrolyzed by this protein. These damaged deoxynucleotides elicit transversion mutations in E. coli (Inoue, M., Kamiya, H., Fujikawa, K., Ootsuyama, Y., Murata-Kamiya, N., Osaki, T., Yasumoto, K., Kasai, H. (1998) J. Biol. Chem. 273, 11069-11074). These results suggest that this protein may be involved in the prevention of mutations induced by these oxidized deoxynucleotides. 相似文献
955.
Osamu Miyaishi Ken-ichi Kozaki Ken-ichi Iida Ken-ichi Isobe Yoshio Hashizume Shinsuke Saga 《Journal of cellular biochemistry》1998,68(4):436-445
We investigated the expression of protein disulfide isomerase family proteins (PDI, ERp61, and ERp72) in mouse F9 teratocarcinoma cells during differentiation induced by treatment with retinoic acid and dibutyryl cAMP. Each member of this family was expressed at a constitutive level in undifferentiated F9 cells. During differentiation of F9 cells to parietal or visceral endodermal cells the protein level of all these enzymes increased, although the extent of this increase in both protein and mRNA levels varied among the enzymes. Certain proteins were found to be co-immunoprecipitated with PDI, ERp61, and ERp72 in the presence of a chemical crosslinker. Type IV collagen was significantly coprecipitated with PDI whereas laminin was equally coprecipitated with the three proteins. Furthermore, 210 kDa protein characteristically coprecipitated with ERp72. Thus, the induction of PDI family proteins during the differentiation of F9 cells and their association with different proteins may implicate specific functions of each member of this family despite the common redox activity capable of catalyzing the disulfide bond formation. J. Cell. Biochem. 68:436–445, 1998. © 1998 Wiley-Liss, Inc. 相似文献
956.
M O Takahashi Y Takahashi K Iida Y Okimura H Kaji H Abe K Chihara 《Biochemical and biophysical research communications》1999,263(1):100-106
Bone is one of the essential target tissues of growth hormone (GH). In bone remodeling, cell-matrix attachment is important where focal adhesion kinase (FAK) is involved. FAK plays a central role in determining the shape and motility of cells in response to the extracellular matrix stimuli. In the present study, we have demonstrated that GH stimulated tyrosine phosphorylation of FAK in human osteoblast-like cells, Saos2. Moreover, GH rapidly enhanced the formation of actin stress fibers. In Saos2, Jak2 was tyrosine phosphorylated by GH stimulation, and AG490, a Jak2 specific inhibitor, inhibited GH-induced tyrosine phosphorylation of FAK and actin stress fiber reorganization. These results suggest that GH activates FAK via Jak2, and stimulates the formation of actin stress fibers in Saos2. Activation of FAK and actin stress fiber formation induced by GH seem to be important for the physiological role of osteoblast. 相似文献
957.
In this study we have used saponin to permeabilize platelet membranes in order to test directly the involvement of IP3 in regulating internal Ca2+ release, and to measure IP3 binding to its receptor. Our results indicate that platelet vesicles release Ca2+ as early as 3 seconds after IP3 addition. Using [3H]IP3, we have found that platelets contain a single class of high affinity IP3 binding sites with a Kd of ~0.20 (± 0.01) nM. Immuno-blotting shows that platelets contain a 260 kDa polypeptide which shares immunological cross reactivity with brain IP3 receptor. Immunofluorescence staining data indicate that the IP3 receptor is preferentially located at the periphery of the platelet plasma membrane. Most importantly, both IP3 binding and IP3-induced Ca2+ release activities are significantly inhibited by cytochalasin D (a microfilament inhibitor) and colchicine (a microtubule inhibitor). These findings suggest that the cytoskeleton is involved in the regulation of IP3 binding and IP3 receptor-mediated Ca2+ release during platelet activation. 相似文献
958.
959.
The permanganate oxidation of thymine 总被引:8,自引:0,他引:8
960.
Splice-site signals of mRNA precursors as revealed by computer search. Site-specific mutagenesis and thalassemia 总被引:2,自引:0,他引:2
Y Iida 《Journal of biochemistry》1985,97(4):1173-1179
Many eukaryotic genes are interrupted by introns, which are removed from mRNA precursors by the RNA splicing mechanism. Although nucleotide sequences around splice sites have considerable homology among various genes, exact splice-site signals are unknown. Previously, applying the computer searching method to primary nucleotide sequences of various genes, we studied what kinds of patterns are the necessary and sufficient sequences for recognition of the 5'-slice site (donor site). We proposed that four common patterns, AG/GTA, /GTAAGT, RG/GTGAG, and AG/GTXXGT, where R = A or G and X = A, T, G, or C, are often used as such signals. In the present paper, we examined a number of experimental results on site-specific mutagenesis around donor sites and on alpha- and beta-thalassemia in globin genes, and found that the above four common patterns could explain almost all of those results. 相似文献