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11.
A new species,Acanthocephaloides cyrusi, is described from the fishesSolea bleekeri andPomadasys commersoni from Lake St. Lucia, Natal, South Africa. It is distinguished from the other species in the genus by the more marked sexual dimorphism in length, the arrangement of hooks, the proboscis with the longest hooks at the anterior-most extremity and the greater size of the proboscis hooks and body spines. An acanthella, which may represent this species, was found in the tanaidApseudes digitalis. 相似文献
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13.
Gemma L. Moir-Meyer John F. Pearson Felicity Lose Rodney J. Scott Mark McEvoy John Attia Elizabeth G. Holliday Paul D. Pharoah Alison M. Dunning Deborah J. Thompson Douglas F. Easton Amanda B. Spurdle Logan C. Walker The Australian National Endometrial Cancer Study Group The Hunter Community Study Studies of Epidemiology Risk Factors in Cancer Heredity 《Human genetics》2015,134(3):269-278
14.
Nirmal Mazumder Rodney K. Lyn Ragunath Singaravelu Andrew Ridsdale Douglas J. Moffatt Chih-Wei Hu Han-Ruei Tsai John McLauchlan Albert Stolow Fu-Jen Kao John Paul Pezacki 《PloS one》2013,8(6)
Hepatitis C virus (HCV) co-opts hepatic lipid pathways to facilitate its pathogenesis. The virus alters cellular lipid biosynthesis and trafficking, and causes an accumulation of lipid droplets (LDs) that gives rise to hepatic steatosis. Little is known about how these changes are controlled at the molecular level, and how they are related to the underlying metabolic states of the infected cell. The HCV core protein has previously been shown to independently induce alterations in hepatic lipid homeostasis. Herein, we demonstrate, using coherent anti-Stokes Raman scattering (CARS) microscopy, that expression of domain 2 of the HCV core protein (D2) fused to GFP is sufficient to induce an accumulation of larger lipid droplets (LDs) in the perinuclear region. Additionally, we performed fluorescence lifetime imaging of endogenous reduced nicotinamide adenine dinucleotides [NAD(P)H], a key coenzyme in cellular metabolic processes, to monitor changes in the cofactor’s abundance and conformational state in D2-GFP transfected cells. When expressed in Huh-7 human hepatoma cells, we observed that the D2-GFP induced accumulation of LDs correlated with an increase in total NAD(P)H fluorescence and an increase in the ratio of free to bound NAD(P)H. This is consistent with an approximate 10 fold increase in cellular NAD(P)H levels. Furthermore, the lifetimes of bound and free NAD(P)H were both significantly reduced – indicating viral protein-induced alterations in the cofactors’ binding and microenvironment. Interestingly, the D2-expressing cells showed a more diffuse localization of NAD(P)H fluorescence signal, consistent with an accumulation of the co-factor outside the mitochondria. These observations suggest that HCV causes a shift of metabolic control away from the use of the coenzyme in mitochondrial electron transport and towards glycolysis, lipid biosynthesis, and building of new biomass. Overall, our findings demonstrate that HCV induced alterations in hepatic metabolism is tightly linked to alterations in NAD(P)H functional states. 相似文献
15.
The nature of the human blood group P1 determinant 总被引:4,自引:0,他引:4
16.
A. E. Watkins 《Journal of genetics》1924,14(2):129-171
17.
We have used the HLA-C-specific DNA probe pC250 to investigate restriction fragment length polymorphism (RFLP) at the HLA-C locus. Genomic Southern blot hybridization included DNA prepared from a panel of homozygous typing cells representing serological specificities Cw1 to Cw8 and also from samples representing Cw blanks. Although many restriction nucleases failed to reveal any polymorphism, RFLPs were evident with Taq I, Pvu II, Bst XI, Nde 1, and Nci I in addition to the previously reported Eco RI. In the case of Bst XI, a unique RFLP defined a subset of serologically defined Cw blanks. Comparison of RFLP sizes with restriction fragment lengths obtained from the known HLA-Cw3 gene sequence permitted the localization of intragenic C locus RFLLs and the identification of a variable Taq I site in the second intron, a variable Nci I site near the end of the fourth exon, and a variable Pvu lI site in the fifth intron. 相似文献
18.
Softening of the flesh and the rise in ethylene evolution and respiration associated with ripening in pear (Pyrus communis L.) fruit was delayed when mannose was vacuum infiltrated into intact fruit. The extent of delay could be modified by altering the concentration or the volume of mannose applied to the fruit. Inhibition of ripening was associated with phosphorylation of mannose to mannose 6-phosphate (M6P), and accumulation of M6P was associated with lowered levels of inorganic phosphate (Pi), glucose 6-phosphate (G6P), and ATP in the fruit tissue. Subsequently, however, as the M6P was metabolized, the levels of Pi, G6P, and ATP increased and ripening processes were concomitantly released from inhibition. Hence, the degree of inhibition by mannose or the release from inhibition was related to the level of M6P in the fruit and its rate of metabolism. The data provide correlative evidence to support a view that one inhibitory effect of mannose is depletion of Pi in the cell as a result of phosphorylation of mannose to M6P. Inhibition of ripening by mannose was not alleviated by co-application of glucose as a competitive substrate for the hexokinase(s), or by Pi, presumably the depleted metabolite. Also, incubation of tissue disks with M6P resulted in inhibition of ethylene production and respiration. The structural analogs of mannose, glucosamine, and 2-deoxyglucose, which have been shown to mimic mannose action in several plant tissues, did not cause inhibition of ripening of pear fruit comparable with that associated with mannose. Both analogs stimulated respiration, and glucosamine caused only a small inhibition of softening and ethylene evolution. Another mannose analog, α-methylmannoside, did inhibit fruit ripening though to a lesser extent than mannose. Its influence was also associated with accumulation of M6P and a decrease of Pi levels. We conclude that the mannose effect may, in part, be due to M6P toxicity, as well as by depletion of Pi. 相似文献
19.
Rodney A. Bray 《Systematic parasitology》1987,9(2):83-123
Summary A detailed revision of the zoogonid subfamily Lepidophyllinae is presented, using morphological characters discussed in an earlier paper. Twelve genera and 50 species are treated in detail with keys and cladograms to genera and species. The genera and species covered are: Lepidophyllum steenstrupi, L. appyi, L. armatum, L. brachycladium, L. cameroni, L. pleuronectini, L. pyriforme, L. schantaricum, Urinatrema hispidum, U. hirudinacea, Panopula cavernossa, P. bridgeri, P. spinosa, Limnoderetrema minutum (Manter, 1954) [formerly Deretrema] n.g. (in freshwater fishes; genital pore at oral sucker or pharynx level), n. comb., Brachyenteron peristedioni, B. acropomatis, B. campbelli, B. doederleiniae, B. magnibursatum, B. parexocoeti, B. pycnorganum, Steganodermatoides kergeleni, S. agassizi, S. allocytti, S. maceri, Neosteganoderma glandulosum, N. infundibulum, Proctophantastes abyssorum, P. gillissi, Deretrema (Deretrema) fusillus, D. (D.) cholaeum, D. (D.) pacificum, D. (Spinoderetrema) plotosi, D. (S.) acutum, D. (S.) fellis, D. (S.) ovale, D.(S.) sebastodis, D. (Luxitrema) philippinensis, D. plagiorchis, Pseudochetosoma salmonicola, Overstreetia sodwanaensis, Steganoderma (Steganoderma) formosum, S. (S.) atherinae, S. (Lecithostaphylus) retroflexum, S. (L.) depauperati (Yamaguti, 1970) n. comb., S. (L.) hemirhamphi, S. (L.) nitens, S. (L.) parexocoeti, S. macrophallos, S. oviformis. Most zoogonids were found to exhibit some level of predilection for a particular piscine host group, but little general information on the zoogeography of the group was discovered. Ultrastructural evidence is presented suggesting that the membranous egg-capsule of the zoogonines shows vestiges of the three layers of a normal tanned egg-shell. 相似文献
20.
The activities of -2-l-fucosyltransferase and -3-l-fucosyltransferase were measured in human platelets and leucocytes from normal donors, -2-l-Fucosyltransferase was found in platelets but not in leucocytes. In contrast -3-l-fucosyltransferase was not detected in platelets but was present in leucocytes where it was demonstrated in the neutrophil, monocyte and lymphocyte fractions. 相似文献