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61.
Genetic analysis of a mutant of Bacillus subtilis producingltraviolet-sensitive spores 总被引:6,自引:0,他引:6
Nobuo Munakata 《Molecular & general genetics : MGG》1969,104(3):258-263
Summary A mutant ofBacillus subtilis, uvssp-42-1, producing UV-sensitive spores was studied genetically. By treatment of the cells with DNA prepared from auvr strain two types,uvs-42 (Hcr−) andssp-1 (Hcr+), of transformants producing UV-resistant spores were obtained. Only strains having both types of mutations together produced
UV-sensitive spores. 相似文献
62.
Structure of the Staphylococcus aureus cell wall determined by the freeze-substitution method. 总被引:9,自引:4,他引:5 下载免费PDF全文
The fine structure of the Staphylococcus aureus cell wall was determined by electron microscopy with the new technique of rapid freezing and substitution fixation. The surface of the cell wall was covered with a fuzzy coat which consisted of fine fibers or an electron-dense mass. Morphological examination of the cell wall, which was treated sequentially with sodium dodecyl sulfate, trypsin, and trichloroacetic acid, revealed that this coat was partially removed by trypsin digestion and was completely removed by trichloroacetic acid extraction but was not affected by sodium dodecyl sulfate treatment, suggesting that the fuzzy coat consists mostly of a complex of teichoic acids and proteins. This was confirmed by the application of the concanavalin A-ferritin technique for teichoic acid and antiferritin immunoglobulin G technique for protein A. 相似文献
63.
Keiji Harashima Nobuo Tsuchida Teruo Tanaka Junsaku Nagatsu 《Bioscience, biotechnology, and biochemistry》2013,77(4):481-489
A water-insoluble red antibiotic pigment was isolated from mycelia of a strain of Streptomyces. It was found that the pigment is a new C25-prodigiosin-analogue and the authors propose to designate it prodigiosin-25 C. The chemical structure (XI) has been deduced from visible absorption spectra, NMR spectra, mass spectra and analysis of degradation products of the pigment. 相似文献
64.
A Ueki Y Fukushima F Hyodoh T Kimoto 《Virchows Archiv. B, Cell pathology including molecular pathology》1978,27(2):155-157
The C3b and C3d receptor sites on one cell line of human diploid fibroblasts (WI-38) were reported in previous papers [3, 4]. In this paper we describe that C3b and C3d receptor sites can also be detected in fibroblast cell lines derived from other human tissues. We consider that C3b and C3d receptors are normally found on the cell surfaces of all human fibroblasts. 相似文献
65.
H. Ueda Takeshi Baba Nobuo Terada Yasuko Kato Shigeo Tsukahara Shinichi Ohno 《Histochemistry and cell biology》1997,108(3):243-248
It is known that the retina contains the protein dystrophin in the ribbon synapse, but the ultrastructural analysis is not
yet fully elucidated. Our previous study reported that dystrophin is localized under the rod cell membranes in rat retinas.
In the present study, we have investigated the relationship between dystrophin-rich regions of rod cell membranes and other
neuronal processes in mouse retinas with a monoclonal antibody raised against the human dystrophin C-terminus. Immunoblotting,
immunofluorescence stainings, and immunoelectron microscopy were employed. Immunoblotting analysis indicated that mouse retinas
possessed some of the dystrophin isoforms of approximately 260 kDa, 140 kDa, and 70 kDa molecular weight. Confocal images
showed a punctate appearance in the outer plexiform layer, as previously described. Immunoelectron microscopy showed that
dystrophin immunoreactive products were always observed at submembranous dense regions of the rod spherule abutting bipolar
processes. These results suggest that retinal dystrophin may be closely involved in signal transmission from rods to bipolar
cells.
Accepted: 7 May 1997 相似文献
66.
67.
Antigenic analyses of Lactobacillus bulgaricus, Lactobacillus lactis, Lactobacillus brevis and Lactobacillus buchneri were carried out by double immunodiffusion in agar. Antigens were extracted from whole cells and cell wall preparations with cold trichloroacetic acid. Most strains of the four species possessed antigen 9 in their cell walls. Another antigen, antigen 10, was found in the cell walls of all the strains of L. brevis and L. buchneri, and in some strains of L. lactis, but not in L. bulgaricus. Fractionation of the antigens was attempted using the cell wall extracts of L. lactis L-10 with only antigen 9 and of L. brevis X-1 with both antigens 9 and 10. The partially purified fractions of antigen 9 and of the complex of antigens 9 and 10 were obtained by zone electrophoresis. However, antigen 10 from the complex could not be separated by the same method or gel filtration on Sephadex G-100 since the two antigens 9 and 10 of the complex always behaved together. The fraction of antigen 9 consisted almost entirely of glycerol and glucose as sugar components, the molar ratio being 2:1. The complex of antigens 9 and 10 also consisted of the same sugars, and the molar ratio of glycerol: glucose was 4:1. Inhibition tests indicated that the immunodominant component of antigen 9 was α-methylglucoside (glucose), and most probably the determinant is a glucosylated glycerol teichoic acid. It was considered that the determinant of antigen 10 is a glycerol teichoic acid although glucosamine and galactosamine inhibited effectively the reaction between antigen 10 and its antibody. 相似文献
68.
Hiroki Koda Alban Lemasson Chisako Oyakawa Rizaldi Joko Pamungkas Nobuo Masataka 《PloS one》2013,8(8)
Mother-infant vocal interactions play a crucial role in the development of human language. However, comparatively little is known about the maternal role during vocal development in nonhuman primates. Here, we report the first evidence of mother-daughter vocal interactions contributing to vocal development in gibbons, a singing and monogamous ape species. Gibbons are well known for their species-specific duets sung between mates, yet little is known about the role of intergenerational duets in gibbon song development. We observed singing interactions between free-ranging mothers and their sub-adult daughters prior to emigration. Daughters sang simultaneously with their mothers at different rates. First, we observed significant acoustic variation between daughters. Co-singing rates between mother and daughter were negatively correlated with the temporal precision of the song’s synchronization. In addition, songs of daughters who co-sang less with their mothers were acoustically more similar to the maternal song than any other adult female’s song. All variables have been reported to be influenced by social relationships of pairs. Therefore those correlations would be mediated by mother-daughter social relationship, which would be modifiable in daughter’s development. Here we hypothesized that daughters who co-sing less often, well-synchronize, and converge acoustically with the maternal acoustic pattern would be at a more advanced stage of social independence in sub-adult females prior to emigration. Second, we observed acoustic matching between mothers and daughters when co-singing, suggesting short-term vocal flexibility. Third, we found that mothers adjusted songs to a more stereotyped pattern when co-singing than when singing alone. This vocal adjustment was stronger for mothers with daughters who co-sang less. These results indicate the presence of socially mediated vocal flexibility in gibbon sub-adults and adults, and that mother-daughter co-singing interactions may enhance vocal development. More comparative work, notably longitudinal and experimental, is now needed to clarify maternal roles during song development. 相似文献
69.
The Miyadera strain of Newcastle disease virus (NDV) consisted predominantly of virus particles forming small plaques on monolayers of chick embryo fibroblasts (CEF), and contained small amounts of virus particles forming large plaques. These large- and small-plaque-forming clones of this virus (NDV-L and NDV-S) were isolated. The small size of the NDV-S plaques did not appear to be due to an agar inhibitor. NDV-L produced a much higher yield of infective virus particles in CEF and they were released more completely from the infected cells than were those produced by NDV-S. The yield of infective virus of NDV-L per cell from cultures of CEF was comparable to the yield from the allantoic cells. The infectivity/hemagglutinin ratio for NDV-L from CEF was as high as the ratio for virus from the allantoic cells, but the ratio for NDV-S from CEF was lower. NDV-S demonstrated an autointerference phenomenon in CEF when infected at high multiplicities, but NDV-L did not. Contrary to virus multiplication, NDV-S exhibited a more rapid and marked cytopathic effect on monolayers of CEF than NDV-L. In the allantoic cavity of eggs NDV-S produced slightly higher virus yields than NDV-L. No correlation existed between plaque size of the two viruses and the capacity to induce interferon synthesis or the susceptibility to the action of interferon. The properties of both distinctive plaque isolates were stable on egg passage. 相似文献
70.