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271.
272.
Morihiro Matsuda Nakaba Sugimoto Kunihiro Ozutsumi Toshihiro Hirai 《Biochemical and biophysical research communications》1982,104(2):799-805
Intravenous injection of purified tetanus toxin(1000-0.06 μg) killed mice within minutes(20–450 min), causing flaccid paralysis indistinguishable from that in botulinum intoxication: a linear relation was found between the log of the toxin dose and that of death time(survival time). The dose and route dependences of the manifestations of the spastic paralysis typical of classical tetanus and of the acute botulinum-like flaccid paralysis were studied in relation to the death time. Treatment of the toxin with trypsin or gangliosides did not affect its acute botulinum-like toxicity. Theophylline delayed the time of acute death due to the botulinum-like intoxication in mice caused by tetanus toxin and provided some protection. 相似文献
273.
H Suzuki A Okubo S Yamazaki K Suzuki H Mitsuya S Toda 《Biochemical and biophysical research communications》1989,160(1):367-373
Inhibition of the infectivity and cytopathic effect of human immunodeficiency virus type 1 (HIV-1) by the immunoactive fractions obtained from LEM, which is an extract of the culture medium of Lentinus edodes mycelia, is reported. A purified fraction, EPS4, obtained from LEM by ethanol precipitation followed by hydrophobic chromatography and gel filtration chromatography completely inhibited the HIV-1 induced cytopathic effect in vitro at concentrations of greater than or equal to 10 micrograms/ml. Chemical and spectral analysis revealed that EPS4 is composed of water-soluble lignins containing minor amounts of protein (3.2%) and sugars (12.2%). Taken together with the previously reported observation that EPS4 promotes the activation of macrophages and the proliferation of bone marrow cells, the fraction appears to possess both an immunostimulating activity and an anti-HIV effect in vitro. 相似文献
274.
Morihiro Notohara 《Journal of mathematical biology》2010,61(5):695-714
The structured coalescent describes the ancestral relationship among sampled genes from a geographically structured population.
The aim of this article is to apply the central limit theorem to functionals of the migration process to study coalescence
times and population structure. An application of the law of large numbers to the migration process leads to the strong migration
limit for the distributions of coalescence times. The central limit theorem enables us to obtain approximate distributions
of coalescence times for strong migration. We show that approximate distributions depend on the population structure. If migration
is conservative and strong, we can define a kind of effective population size N
e
*, with which the entire population approximately behaves like a panmictic population. On the other hand, the approximate distributions
for nonconservative migration are qualitatively different from those for conservative migration. And the entire population
behaves unlike a panmictic population even though migration is strong. 相似文献
275.
Synthesis of phosphorothioate analogues of oligodeoxyribonucleotides and their antiviral activity against human immunodeficiency virus (HIV) 总被引:8,自引:0,他引:8
Nuclease-resistant phosphorothioate analogues of oligodeoxynucleotides (oligos) were synthesized by sulfurization of either internucleoside phosphite linkages, in a repetitive manner during chain extension, or internucleoside hydrogen phosphonate linkages, in a single step following chain assembly. These analogues were tested as antiviral agents against human immunodeficiency virus (HIV). In a cytopathic effect inhibition assay using HIV-uninfected susceptible T cells (tetanus toxoid-specific normal T cells) co-cultured with irradiated chronically HIV-infected cells, phosphorothioate oligomers inhibited the cytopathic effect and replication of several isolates of HIV-1 and HIV-2. Thus phosphorothioate analogues of oligos could inhibit cell-to-cell transmission of the virus as well as the infection by cell-free virus particles and also could inhibit a variety of isolates of human retroviruses. 相似文献
276.
Root-knot nematodes (RKNs, genus Meloidogyne) are a class of plant parasites that seek out and infect the roots of many plant species. The identification of RKN attractants can be used in agriculture in conjunction with nematode-trapping technology to redirect RKN movements and eventually reduce their prevalence in the field. Here, we discovered that some commercial silica gels can attract nematodes. Silica gels that attract nematodes contain calcium sulfate. Calcium sulfate and calcium carbonate showed strong nematode attraction properties. When plant seeds were surrounded by calcium sulfate or calcium carbonate, nematodes were not attracted to the plant seeds. We propose that calcium sulfate and calcium carbonate can be used in agriculture as a novel material to trap RKN. 相似文献