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991.
Nucleotide sequence of a transmembrane protein (TMP-C) cDNA in Arabidopsis thaliana. 总被引:2,自引:1,他引:1
T Kinoshita I Hara-Nishimura H Siraishi K Okada Y Shimura M Nishimura 《Plant physiology》1994,105(4):1441-1442
992.
Mamoru Mimuro Tsunenori Nozawa Naoto Tamai Yoshinobu Nishimura Iwao Yamazaki 《FEBS letters》1994,340(3):167-172
Antenna components in the energy transfer processes of a green photosynthetic bacterium Chloroflexus aurantiacus were spectrally investigated by time-resolved fluorescence spectroscopy at −196°C on intact cells. Besides major antenna components so far reported, three minor components were resolved; those were Bchl c located at 785 nm, the baseplate Bchl a at 819 nm and Bchl a in the B808-866 complex at 910 nm. The last component was assigned to a longer wavelength antenna closely associated with a reaction center. An additional Bchl c fluorescence component was kinetically suggested to be present, which can be an energy donor to a major Bchl c. Presence of these minor components was signified in terms of (1) increase in the spectral overlap integral and (2) adjustment of the direction of dipole moments in the energy transfer sequence of intact cells. 相似文献
993.
Hiroshi Takemoto Shinji Nishimura Yumi Kosada Satoshi Hata Shin Takagi Susumu Hosoi Kiyoshi Ezumi Misao Ide Shigenori Harada 《Microbiology and immunology》1994,38(1):63-71
Anti-human IgE monoclonal antibodies (mAbs) were produced and eight clones recognizing epitopes on native IgE were selected. Epitopes were mapped by a competitive inhibition enzyme-linked immunosorbent assay, Western blotting and a multi-pin peptide technology. Four sites (one each in the Cε1, Cε2, Cε2/Cε3 junction and Cε3) were recognized by the mAbs. The relationship between the four epitopes and the binding sites of high and low affinity IgE receptors (FcεRI and FcεRII, respectively) was studied using a monovalent Fab fragment of each mAb as a binding inhibitor. The IgE-FcεRII binding was clearly inhibited by the mAb recognizing the Cε2/Cε3 junction, suggesting that FcεRII binds to a rather limited area around the Cε2/Cε3 junction. The IgE-FcεRI binding, on the other hand, was scarcely inhibited by any single mAb. However, the binding was inhibited when the epitope in Cε2 was blocked simultaneously with that at the Cε2/Cε3 junction or with that in Cε3, indicating that these three distinct epitopes are related to the FcεRI binding sites. When these three epitopes were shown in the stereograph of human IgE, the FcεRI binding area was spread largely on the groove side between Cε2 and Cε3 domains. These results suggest that FcεRI acquires the high affinity through multiple bindings. 相似文献
994.
The development of so-called foliose pseudoparaphyllia in the species of theClimacium-type branch development was studied with a paraffin sectioning method and SEM. Scaly leaves (or scale-like leaves) and “foliose”
pseudoparaphyllia proved to originate as leaves by segmentation of an apical cell of a branch initial in the very first stage
of development into a branch bud.
Branch buds of two species among the six species examined develop linear-lanceolate appendages which serve to protect the
buds as well as scaly leaves. These appendages originate in the peripheral part of the epidermal layer of buds, and therefore
they can be homologous to trichomes previously reported for species with branch primordia.
Emendation of two terms are proposed; every organ originating from buds as leaves that are effective for bud protection should
be called scaly leaves, while those which homologous to trichomes should be called pseudoparaphyllia. Both terms are used
here in a narrower sense than before: There might befilamentous orfoliose scaly leaves, andfilamentous orfoliose (linear-to broad-lanceolate) pseudoparaphyllia.
A scheme is given to show the pattern of branch development and the manner in which branch buds (or primordia) are protected. 相似文献
995.
Yutaka Muto Kazuhiko Yamasaki Yutaka Ito Shunsuke Yajima Haruhiko Masaki Takeshi Uozumi Markus Wälchli Susumu Nishimura Tatsuo Miyazawa Shigeyuki Yokoyama 《Journal of biomolecular NMR》1993,3(2):165-184
Summary All the backbone 1H and 15N magnetic resonances (except for Pro residues) of the GDP-bound form of a truncated human c-Ha-ras proto-oncogene product (171 amino acid residues, the Ras protein) were assigned by 15N-edited two-dimensional NMR experiments on selectively 15N-labeled Ras proteins in combination with three-dimensional NMR experiments on the uniformly 15N-labeled protein. The sequence-specific assignments were made on the basis of the nuclear Overhauser effect (NOE) connectivities of amide protons with preceding amide and/or Cprotons. In addition to sequential NOEs, vicinal spin coupling constants for amide protons and C protons and deuterium exchange rates of amide protons were used to characterize the secondary structure of the GDP-bound Ras protein; six strands and five helices were identified and the topology of these elements was determined. The secondary structure of the Ras protein in solution was mainly consistent with that in crystal as determined by X-ray analyses. The deuterium exchange rates of amide protons were examined to elucidate the dynamic properties of the secondary structure elements of the Ras protein in solution. In solution, the -sheet structure in the Ras protein is rigid, while the second helix (A66-R73) is much more flexible, and the first and fifth helices (S17-124 and V152-L171) are more rigid than other helices. Secondary structure elements at or near the ends of the effector-region loop were found to be much more flexible in solution than in the crystalline state. 相似文献
996.
Keisuke Kurita Hitoshi Yoshino Shin-Ichiro Nishimura Shigeru Ishii 《Carbohydrate polymers》1993,20(4):239-245
Cell walls of glasswort (Salicornia ramosissima Woods), a halophytic Chenopodiaceae, prepared as alcohol-insoluble solids, were found to be rich in arabinose, galacturonic acid, glucose and proteins, and contained 0·7% ferulic acid and 3·8% acetic acid. Pectic and hemicellulosic polysaccharides were extracted by cyclohexanediaminotetraacetic acid, hot dilute acid, cold dilute alkali and concentrated alkali (twice), with yields of 2·9, 19·1, 4·7, 7·4 and 1·9% of the alcohol-insoluble solids, respectively. Protein-rich material precipitated upon dialysis. The dialysed fractions were fractionated by ion-exchange chromatography, and the main fractions were analysed by gel-filtration and glycosyl linkage analysis. The hot acid extract contained 46·2% arabinose and 28·9% galacturonic acid, with high degrees of methylation and acetylation (65 and 45, respectively). It could be fractionated into a low-molecular-weight arabinan rich in ferulic acid, and a pectic fraction still relatively rich in neutral sugars. The concentrated alkali extracts were rich in xylose (33·4 and 23·6%, respectively). They were separated by ion-exchange chromatography into a fucogalactoxyloglucan and a glucuronoarabinoxylan. 相似文献
997.
Mitochondrial DNA(mtDNA) analysis with restriction enzymes, Hae III, Hind III and Msp I was performed in 17Exophiala moniliae strains. The results were as follows: (1)E. moniliae could be classified into 10 types based on restriction patterns, (2)E. moniliae is suggested to be a complex organism because of extensive mtDNA polymorphism among strains likeE. jeanselmei and (3) two types ofE. moniliae are identical with two types ofE. jeanselmei. These results suggest thatE. moniliae is not genetically defined fromE. jeanselmei and the taxonomical status ofE. moniliae requires reevaluation 相似文献
998.
chpA and chpB, Escherichia coli chromosomal homologs of the pem locus responsible for stable maintenance of plasmid R100. 总被引:7,自引:3,他引:4 下载免费PDF全文
The pem locus is responsible for stable maintenance of plasmid R100 and consists of two genes, pemI and pemK. The pemK gene product is a growth inhibitor, while the pemI gene product is a suppressor of this inhibitory function. We found that the PemI amino acid sequence is homologous to two open reading frames from Escherichia coli called mazE and orf-83, which are located at 60 and 100 min on the chromosome, respectively. We cloned and sequenced these loci and found additional open reading frames, one downstream of each pemI homolog, both of which encode proteins homologous to PemK. The pem locus homolog at 60 min was named chpA and consists of two genes, chpAI and chpAK; the other, at 100 min, was named chpB and consists of two genes, chpBI and chpBK. The distal portion of chpBK was found to be adjacent to the ppa gene that encodes pyrophosphatase, whose map position had not been previously determined. We then demonstrated that the chpAK and chpBK genes encode growth inhibitors, while the chpAI and chpBI genes encode suppressors for the inhibitory function of the ChpAK and ChpBK proteins, respectively. These E. coli pem locus homologs may be involved in regulation of cell growth. 相似文献
999.
Yasushi Shigemori Junko Inagaki Hitoshi Mori Mikio Nishimura Sumio Takahashi Yasusi Yamamoto 《Plant molecular biology》1994,24(1):209-215
A cDNA clone for the extrinsic 30 kDa protein (OEC30) of photosystem II in Euglena gracilis Z was isolated and characterized. The open reading frame of the cDNA encoded a polypeptide of 338 amino acids, which consisted of a long presequence of 93 amino acids and a mature polypeptide of 245 amino acids. Two hydrophobic domains were identified in the presequence, in contrast to the presence of a single hydrophobic domain in the presequence of the corresponding proteins from higher plants. At the N- and C-terminal regions, respectively, of the presequence, a signal-peptide-like sequence and a thylakoid-transfer domain were identified. The presence of a long and unique presequence in the precursor to OEC30 is probably related to the complexity of the intracellular processes required for the synthesis and/or transport of the protein in Euglena.Abbreviations ER
endoplasmic reticulum
- cDNA
complementary DNA
- SSU
small subunit; Rubisco, ribulose 1,5-bisphosphate carboxylase/oxygenase
- Rubico, ribulose 1,5
bisphosphate carboxylase/oxygenase
- LHC II
light-harvesting chlorophyll protein of photosystem II
- PS II
photosystem II
- OEC30
the extrinsic 30 kDa protein of photosystem II in Euglena
- PCR
polymerase chain reaction
- SDS
sodium dodecyl sulfate
- TE
a solution containing 10 mM Tris-HCl and 1 mM EDTA pH 8.0
- SSPE
a solution containing 0.15 M NaCl, 10 mM NaH2PO4 and 1 mM EDTA pH 7.4
- SDS-PAGE
sodium dodecyl sulfate-polyacrylamide gel electrophoresis
- PVDF
poly(vinylidene difluoride) 相似文献
1000.
Mark Ming-Long Hsu MD Jen-Chyi Chang Koji Yokoyama Kazuko Nishimura Makoto Miyaji 《Mycopathologia》1994,127(2):77-81
Twenty-one strains ofCryptococcus neoformans isolated from patients in Taiwan were characterized for serotypes and mating types. Slide agglutination test was performed with 8 factor-specific sera (Iatron Company, Japan) to determine the serotypes. Wheat bran agar (WBA) and malt extract agar (MEA, Wickerham) media were used for the mating tests. Twenty of the isolates were of serotype A, and one was serotype B. Except for 2 strains of serotype A, all of the serotype A strains mated withFilobasidiella neoformans var.neoformans, mating type a. The only serotype B strain mated withF. neoformans var.bacillispora mating type a in MEA medium. These data revealed the low prevalence (1/21; 4.8%) ofC. neoformans var.gattii in Taiwan, a subtropically located island. 相似文献