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11.
Naoko Morioka Lan L. Sze Donald L. Morton Reiko F. Irie 《Cancer immunology, immunotherapy : CII》1993,37(5):316-322
Fraction 4 (F4), a protein fraction isolated from aged garlic extract, enhanced cytotoxicity of human peripheral blood lymphocytes (PBL) against both naturalkiller (NK)-sensitive K562 and NK-resistant M14 cell lines. Although F4 treatment alone increased cytotoxicity, the effect was more remarkable when F4 was administered together with suboptimal doses of interleukin-2 (IL-2); combination treatment of 5 g/ml F4 plus 10 U/ml IL-2 for 72 h generated lymphokine-activated killer activity equivalent to that produced by 100 U/ml IL-2 alone against M14. F4 enhanced IL-2-induced proliferation and IL-2 receptor (Tac) expression of PBL without significant increase of IL-2 production. The enhancement of cytotoxicity both by F4 alone and by F4 plus IL-2 was abolished by anti-IL-2 antibody. F4 also enhanced concanavalin-A(ConA)-induced proliferation of PBL. Radiolabeled-ConA binding assays revealed that F4 treatment greatly augmented the affinity and slightly increased the number of ConA binding sites in PBL. F4 also enhanced ConA-induced IL-2 receptor (Tac) expression and IL-2 production of PBL. Anti-IL-2 antibody inhibited the effect of F4 on ConA-induced proliferation. These data suggest that IL-2 is involved in augmentative effects of F4. Our results indicate that F4 is a very efficient immunopotentiator and may be used for immunotherapy. 相似文献
12.
13.
Acetyl esterase production was detected in a wood-rotting fungus,Coriolus versicolor, by the formation of a clear zone on a double layer agar plate containing glucose β-d-pentaacetate. Two polysaccharide acetates, carboxymethyl cellulose acetate and xylan acetate, also served as detectable substrates
in place of glucose acetate to form clear zone. In an esterase assay, this fungal esterase showed a higher specificity to
acetylxylan than did porcine liver esterase, indicating that it is an acetylxylan esterase. 相似文献
14.
Naoko Sakihama Izumi Nishimura Shigehiro Obata Masateru Shin 《Photosynthesis research》1995,46(1-2):323-328
When 35%-acetone extract of spinach chloroplasts was separated by SDS-PAGE, ferredoxin-NADP reductase (FNR) appeared as a single band at a molecular mass of 35 kDa. After the polypeptides on the SDS-PAGE plate were electroblotted onto PVDF membrane, the FNR band was cut out and analyzed for N-terminal structure in a gas-phase protein sequencer. Two different FNR peptides were identified: one with glutamine at its N-terminus (Gln-FNR) and the other with -pyroglutamic acid (tFNR) fraction was extracted from chloroplasts with their loosely bound FNR (lFNR) fraction removed in advance. The tFNR fraction contained Gln-FNR only. The Gln-FNR could be highly purified by affinity chromatography using a ferredoxin column. The purified Gln-FNR was digested with arginyl endopeptidase for peptide mapping and partial sequence analysis. Primary structure of Gln-FNR differed from that of lFNR
loosely bound FNR
-
tFNR
tightly bound FNR
- -pyroglutamic acid at N-terminus 相似文献
15.
T. Ito Naoko Udaka Yoshiaki Inayama Hitoshi Kitamura Masayoshi Kanisawa 《Histochemistry and cell biology》1997,109(1):67-73
We have examined the distribution of calcium-binding proteins (CaBPs) in adult and fetal lungs of Syrian golden hamsters
(Mesocricetus auratus) using immunostaining with confocal laser microscopy and electron microscopy. Single and grouped (neuroepithelial body; NEB)
endocrine cells were distributed from bronchi to alveolar ducts in the adult lung. Serial frozen sections immunostained for
CaBPs in combination with immunostaining for endocrine markers such as calcitonin gene-related peptide, serotonin, PGP9.5,
and synaptophysin revealed that positive immunostaining for calbindin-D28K (CB-D28K) was seen in single endocrine cells and NEBs. However, other so-called EF-hand family CaBPs, parvalbumin and calretinin,
were not detected. Electron microscopically, positive immunoreaction for CB-D28K was mainly in the organelle-free cytoplasmic
matrix of endocrine cells, and partly in nuclei and associated with secretory granules and endoplasmic reticulum. In fetal
developing lungs, endocrine cells appeared first on gestational day 13, and they were positive for all the endocrine markers
used. However, pulmonary endocrine cells were positively immunostained for CB-D28K from gestational days 15 and 16 onward.
In summary, our observations suggest that CB-D28K is a useful marker for endocrine cells of the lung, and CB-D28K could function
as a mediator of endocrine stimulation or calcium homeostasis in pulmonary endocrine cells.
Accepted: 17 June 1997 相似文献
16.
Koichiro Suzuki Kenji Kanazawa Kyoko Higuchi Naoko K. Nishizawa Satoshi Mori 《Biometals》1997,10(2):77-84
In a previous paper we reported that an acidic 36 kDa peptide is the most strongly induced peptide among several peptides induced by Fe deficiency in barley roots. In this paper, polyclonal antibodies were raised against the 36 kDa peptide. This peptide appeared in the roots of all the graminaceous species tested (barley, rye, wheat, oat, maize, sorghum and rice) in response to Fe deficiency. More of the peptide was found in the roots of graminaceous species which secrete higher amounts of mugineic acids (MAs) under Fe deficient nutrition status. Induction of the 36 kDa peptide was first observed on the third day of Fe deficiency, rising to a maximum value on the seventh day. The trend has a positive correlation with secretion of MAs during Fe deficiency. Further, resupply of Fe resulted in a decrease in peptide production on the second day, reaching a control level on the seventh day. The rate of decrease in peptide production was observed to be slower than that of MA secretion. Other nutrient stresses such as B excess, B deficiency, Cu excess, Cu deficiency, Mn excess, Mn deficiency, Zn excess and Zn deficiency induced far less of the peptide. The specific expression of the 36 kDa peptide in roots of graminaceous species under Fe deficiency suggested the positive association of the peptide with a specific Fe deficiency tolerance mechanism in graminaceous plants. 相似文献
17.
Minoru Yonezawa Masahiro Takahata Naoko Banzawa Nobuyuki Matsubara Yasuo Watanabe Hirokazu Narita 《Microbiology and immunology》1995,39(4):243-247
Artificial mutations of Gyrase A protein (GyrA) in Escherichia coli by site-directed mutagenesis were generated to analyze quinolone-resistant mechanisms. By genetic analysis of gyrA genes in a gyrA temperature sensitive (Ts) background, exchange of Ser at the NH2-terminal 83rd position of GyrA to Trp, Leu, Phe, Tyr, Ala, Val, and Ile caused bacterial resistance to the quinolones, while exchange to Gly, Asn, Lys, Arg and Asp did not confer resistance. These results indicate that it is the most important for the 83rd amino acid residue to be hydrophobic in expressing the phenotype of resistance to the quinolones. These findings also suggest that the hydroxyl group of Ser would not play a major role in the quinolone-gyrase interaction and Ser83 would not interact directly with other amino acid residues. 相似文献
18.
Yasushi Isashiki Norio Ohba Toyoko Yanagita Naoko Hokita Norihito Doi Masanori Nakagawa Masayuki Ozawa Noriko Kuroda 《Human genetics》1995,95(1):105-108
We have identified a new mutation of Norrie disease (ND) gene in two Japanese males from unrelated families; they showed typical ocular features of ND but no mental retardation or hearing impairment. A mutation was found in both patients at the initation codon of exon 2 of the ND gene (ATG to GTG), with otherwise normal nucleotide sequences. Their mothers had the normal and mutant types of the gene, which was expected for heterozygotes of the disease. The mutation of the initiation codon would cause the failure of ND gene expression or a defect in translation thereby truncating the amino terminus of ND protein. In view of the rarity and marked heterogeneity of mutations in the ND gene, the present apparently unrelated Japanese families who have lived in the same area for over two centuries presumably share the origin of the mutation. 相似文献
19.
20.
Purification and properties of a lytic enzyme from the cell wall of Chlorella ellipsoidea C-87 总被引:1,自引:0,他引:1
Cell wall lytic activity was detected in the culture medium and cell wall of 1AM Chlorella ellipsoidea C-87. The enzymes of both fractions had their highest activity at pH 5. The lytic activity bound to the cell wall consisted of a polysaccharide releasing enzyme, an exo-type enzyme releasing disaccharide, and glucosidase; but only the polysaccharide releasing enzyme was solubilized by lithium chloride. A polysaccharide releasing enzyme with a molecular weight around 40 kDa was isolated from the culture medium. Hemicellulose is degraded by the polysaccharide releasing enzyme, and the rigid wall by the exo-type enzyme. 相似文献