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1.
M Shadidy X Caubit R Olsen O M Seternes U Moens S Krauss 《Biochimica et biophysica acta》1999,1446(3):295-307
We have identified mouse and human FKBP60, a new member of the FKBP gene family. FKBP60 shares strongest homology with FKBP65 and SMAP. FKBP60 contains a hydrophobic signal peptide at the N-terminus, 4 peptidyl-prolyl cis/trans isomerase (PPIase) domains and an endoplasmic reticulum retention motif (HDEL) at the C-terminus. Immunodetection of HA-tagged FKBP60 in NIH-3T3 cells suggests that FKBP60 is segregated to the endoplasmic reticulum. Northern blot analysis shows that FKBP60 is predominantly expressed in heart, skeletal muscle, lung, liver and kidney. With N-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide as a substrate, recombinant GST-FKBP60 is shown to accelerate effectively the isomerization of the peptidyl-prolyl bond. This isomerization activity is inhibited by FK506. mFKBP60 binds Ca2+ in vitro, presumably by its C-terminal EF-hand Ca2+ binding motif, and is phosphorylated in vivo. hFKBP60 has been mapped to 7p12 and/or 7p14 by fluorescence in situ hybridization (FISH). 相似文献
2.
B Spyropoulos P B Moens J Davidson J A Lowden 《American journal of human genetics》1981,33(3):375-380
Chi-square analyses of new data as well as data previously reported by Myrianthopoulos have shown that grandparents of Tay-Sachs carriers die from proportionally the same causes as grandparents of noncarriers. It is unlikely that there is any advantage to being a Tay-Sachs carrier insofar as resistance to tuberculosis is concerned. Our results are further evidence to support Fraikor's claim that the high carrier frequency of the allele in Ashkenazi Jews is probably caused by a combination of founder effect, genetic drift, and differential immigration patterns. 相似文献
3.
The fine structure of meiotic chromosome pairing in natural and artificial Lilium polyploids 总被引:1,自引:0,他引:1
P B Moens 《Journal of cell science》1970,7(1):55-63
4.
Synaptonemal complex (SC) analysis of six laboratory yeast strains showed the SC karyotypes to be repeatable within strains. Chromosomal differences were found between strains. In five of the strains, two SCs insert into the nucleolus. This represents a single bivalent with a nucleolar organizer in a medial position as is suggested by genetic data or two bivalents each with a terminal nucleolar organizer. In the first interpretation, n=16; in the second, n=17. Strain Tris has a single nucleolar SC and n=17. In strains DCx374, DCx416 and x 8366a the genetically determined rearrangements of linkage group III could not be identified. Presumably the short SC (0.33 m) associated with linkage group III cannot accommodate an inversion loop or a translocation configuration. The strains however were found to harbour a reciprocal translocation involving the nucleolar chromosome. Trisomy for one of the longer chromosomes was observed in Tris and spo10. It is concluded that rearrangements of the medium and long but not short yeast chromosomes can be detected cytologically. — Measurements of nuclear volumes show SC length to vary with artifactually induced swelling of the nucleus. Linear regression of SC length over nuclear radius indicates that actual SC length is only about one-half the observed length. As a result the DNA packing per SC unit length is higher then previously estimated. 相似文献
5.
immunocytochemical localization of urokinase-type plasminogen activator in lewis lung carcinoma 总被引:1,自引:0,他引:1 下载免费PDF全文
L Skriver LI Larsson V Kielberg LS Nielsen PB Andresen P Kristensen K Dano 《The Journal of cell biology》1984,99(2):753-758
The invasively growing and metasizing Lewis lung carcinoma consistently contained urokinase-type plasminogen activator (u-PA) enzyme activity. When investigated immunocytochemically with antibodies against u-PA, different parts of individual tumors showed a pronounced heterogeneity in staining intensity. Strong staining was found in areas with invasive growth and degradation of surrounding normal tissue, while other areas were completely devoid of staining. Immunoreactivity occurred both with a perinuclear cytoplasmic localization in tumor cells and associated with apparently extracellular material. SDS PAGE of tumor extracts, under both reducing and nonreducing conditions, followed by immunoblotting, showed only one immunocytochemically stainable band with an electrophoretic mobility corresponding to that of purified proenzyme to u-PA, while no two-chain u-PA was detected. This indicates that the major part of the activator in Lewis lung carcinoma is present as one-chain pro-u-PA. 相似文献
6.
L. Moens J. Vanfleteren I. De Baere A.M. Jellie W. Tate C.N.A. Trotman 《FEBS letters》1993,320(3):284-287
7.
Cloning, sequencing, and phenotypic analysis of laf1, encoding the flagellin of the lateral flagella of Azospirillum brasilense Sp7. 总被引:3,自引:3,他引:0 下载免费PDF全文
S Moens K Michiels V Keijers F Van Leuven J Vanderleyden 《Journal of bacteriology》1995,177(19):5419-5426
Azospirillum brasilense can display a single polar flagellum and several lateral flagella. The A. brasilense Sp7 gene laf1, encoding the flagellin of the lateral flagella, was isolated and sequenced. The derived protein sequence is extensively similar to those of the flagellins of Rhizobium meliloti, Agrobacterium tumefaciens, Bartonella bacilliformis, and Caulobacter crescentus. An amino acid alignment shows that the flagellins of these bacteria are clustered and are clearly different from other known flagellins. A laf1 mutant, FAJ0201, was constructed by replacing an internal part of the laf1 gene by a kanamycin resistance-encoding gene cassette. The mutant is devoid of lateral flagella but still forms the polar flagellum. This phenotype is further characterized by the abolishment of the capacities to swarm on a semisolid surface and to spread from a stab inoculation in a semisolid medium. FAJ0201 shows a normal wheat root colonization pattern in the initial stage of plant root interaction. 相似文献
8.
The normal association between the X and Y chromosomes at metaphase I of meiosis, as seen in air-dried light microscope preparations of mouse spermatocytes, is frequently lacking in the spermatocytes of the sterile interspecific hybrid between the laboratory mouse strains C57BL/6 and Mus spretus. The purpose of this work is to determine whether the separate X and Y chromosomes in the hybrid are asynaptic, caused by failure to pair, or desynaptic, caused by precocious dissociation. Unpaired X-Y chromosomes were observed in air-dried preparations at diakinesis, just prior to metaphase I. Furthermore, immunocytology and electron microscopy studies of surface-spread pachytene spermatocytes indicate that the X and Y chromosomes frequently fail to initiate synapsis as judged by the failure to form a synaptonemal complex between the pairing regions of the X and Y Chromosomes. Several additional chromosomal abnormalities were observed in the hybrid. These include fold-backs of the unpaired X or Y cores, associations between the autosome and sex chromosome cores, and autosomal univalents. The occurrence of abnormal autosomal and XY-autosomal associations was also correlated with cell degeneration during meiotic prophase. The primary breakdown in hybrid spermatogenesis occurs at metaphase I (MI), with the appearance of degenerated cells at late MI. In those cells, the X and Y are decondensed rather than condensed as they are in normal mouse MI spermatocytes. These results, in combination with the previous genetic analysis of spermatogenesis in hybrids and backcrosses with fertile female hybrids, suggest that the spermatogenic breakdown in the interspecific hybrid is primarily correlated with the failure of XY pairing at meiotic prophase, asynapsis, followed by the degeneration of spermatocytes at metaphase I. Secondarily, the failure of XY pairing can be accompanied by failure of autosomal pairing, which appears to involve an abnormal sex vesicle and degeneration at pachytene or diplotene.by C. Heyting 相似文献
9.
Hanne Steel Freija Verdoodt Andrea Čerevková Marjolein Couvreur Pamela Fonderie Tom Moens Wim Bert 《Invertebrate Biology》2013,132(2):108-119
Nematodes are omnipresent in composts and are active in virtually all stages of the composting process. Major shifts in species composition, life strategies, and feeding behavior occur during the composting process. Due to the heat peak, nematodes can be virtually absent, but several taxa appear immediately when the temperatures drop. These comprise both taxa present before the heat peak and new taxa. However, it is not known how nematodes populate the compost. In this study, we aimed to assess the survival and colonization capacity of nematodes in compost. Our results showed that composting processes inaccessible to insects or not in contact with soil did not significantly influence nematode succession during composting. However, differences between treatments were found for some specific taxa (i.e., for Acrostichus sp., Neodiplogasteridae sp., Nygolaimoides sp., and Rhabditidae sp. 1), illustrating the importance of insects for the dispersal of nematodes to compost. Experiments in the lab with the blue bottle fly as a possible carrier demonstrated actual transport of nematodes isolated from compost by the fly (i.e., Halicephalobus cfr. gingivalis, Diploscapter coronatus, Diplogasteritus sp., Acrostichus sp., and Mesorhabditis sp.). Juveniles and dauer stages of Aphelenchoides sp., Panagrolaimus sp., and rhabditids survived an experimentally induced temperature peak, while members of Tylenchidae did not. In conclusion, our results indicate that the rapidly changing nematode community in compost is the result of both differential survival and colonization capacities. 相似文献
10.