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991.
Yumiko Kikuchi Toshio Teramura Jun Sekino Tetsuya Nishimura Hiroya Miura Takashi Watanabe Saburo Higuchi 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,720(1-2):81-87
A highly sensitive and specific method for the determination of josamycin in human plasma by LC–MS was developed and validated. Josamycin was extracted from human plasma by a single-step liquid–liquid extraction and analyzed by LC–MS via an electrospray ionization interface. Selected ion monitoring was used to detect josamycin and its internal standard. The intra-day precision and accuracy, expressed as C.V. and R.E., ranged from 2.8% to 13.5% and −10.3% to 7.6%, respectively. The lower limit of detection was 0.1 ng/ml and the lower limit of quantitation was set at 1 ng/ml when 0.5 ml of plasma was used. No endogenous interference was observed in human plasma obtained from drug-free volunteers. 相似文献
992.
Luigi De Bellis Makoto Hayashi Pier Paolo Biagi Ikuko Hara-Nishimura Amedeo Alpi Mikio Nishimura 《Physiologia plantarum》1994,90(4):757-762
Aconitase (EC 4.2.1.3) was purified by column chromatography and SDS-PAGE. Specific antibodies for aconitase were prepared after affinity purification of the antiserum with purified aconitase. The antibodies reacted with purified pumpkin aconitase, and with the 98 kDa protein band after electrophoretic fractionation of extracts of pumpkin cotyledons. Immunoblot analysis revealed a protein with similar molecular mass in extracts of several plants. The intensity of the 98 kDa band increased as pumpkin cotyledons developed in darkness, and decreased thereafter upon illumination. Aconitase activity showed a similar pattern. Anion exchange chromatography of a homogenate of pumpkin cotyledons, followed by western blotting, displayed the presence of immunoreactive protein bands only in fractions showing aconitase activity. The results indicate that the antibodies were specific for aconitase. When we investigated the presence of immunoreactive bands after sucrose gradient fractionation, aconitase was detected in the supernatant fractions and in mitochondria, while a very low amount was found in glyoxysomes. These data provide additional proof that aconitase is not localized in glyoxysomes. 相似文献
993.
Kusumi Kensuke; Inada Hitoshi; Kawabata Shun-ichiro; Iba Koh; Nishimura Mitsuo 《Plant & cell physiology》1994,35(3):445-449
Temperature-sensitive mutants of rice, designated virescent(v1, v2 and v3), develop chlorophyll-deficient leaves at a restrictivetemperature (20°C) but develop nearly normal green leavesat a permissive temperature (30°C). Analysis of the chlorophyllbiosynthetic pathway in the virescent mutants indicated thatthe chlorophyll deficiency at the restrictive temperature wasdue to specific blockage of the C5-pathway. Northern analysissuggested that the chlorophyll deficiency in the virescent mutantswas caused by specific inhibition of the expression of chloroplasttRNAGlu. (Received October 22, 1993; Accepted January 25, 1994) 相似文献
994.
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
995.
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
996.
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
997.
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
998.
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
999.
Ubiquinone systems of Coccidioides immitis, the causative agent of coccidioidomycosis 总被引:1,自引:0,他引:1
Kazutaka Fukushima Kayoko Takizawa Kaoru Okada Yukio Maebayashi Kazuko Nishimura Makoto Miyaji Paul E. Brummer Karl V. Clemons David A. Stevens 《FEMS microbiology letters》1993,108(2):243-245
Abstract The ubiquinone (coenzyme Q) systems of eleven strains of Coccidioides immitis were determined by high performance liquid chromatography (HPLC). The ubiquinone profile of the fungi was shown to be homogeneous: in all of the strains, ubiquinone-10 (Q-10) was demonstrated to be the major component, with Q-9 as a minor component. The results imply that the ubiquinone system may serve as an additional phenotypic criterion for identifying the fungus. 相似文献
1000.
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