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1.
Nicole LeBrasseur 《The Journal of cell biology》2003,162(6):958-959
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Variability in Brain Gangliosides of Fishes 总被引:1,自引:1,他引:0
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A simple, sensitive and reliable assay for serotonin and 5-HIAA in brain tissue using liquid chromatography with electrochemical detection 总被引:11,自引:0,他引:11
An extremely sensitive and simple method for simultaneously measuring both serotonin and 5-hydroxyindoleacetic acid (5-HIAA) has been developed using liquid chromatography (LC) and electrochemical detection. Assay conditions are described which resolve and measure as little as 22 picograms of serotonin and its deaminated metabolite in deproteinated brain samples. 相似文献
6.
Ribonuclease III: new sense from nuisance. 总被引:6,自引:0,他引:6
Christian Conrad Reinhard Rauhut 《The international journal of biochemistry & cell biology》2002,34(2):116-129
RNases play an important role in the processing of precursor RNAs, creating the mature, functional RNAs. The ribonuclease III family currently is one of the most interesting families of endoribonucleases. Surprisingly, RNase III is involved in the maturation of almost every class of prokaryotic and eukaryotic RNA. We present an overview of the various substrates and their processing. RNase III contains one of the most prominent protein domains used in RNA-protein recognition, the double-stranded RNA binding domain (dsRBD). Progress in the understanding of this domain is summarized. Furthermore, RNase III only recently emerged as a key player in the new exciting biological field of RNA silencing, or RNA interference. The eukaryotic RNase III homologues which are likely involved in this process are compared with the other members of the RNase III family. 相似文献
7.
Brigitte Aupetit Alexandre Ghazi Nicole Blanchouin Ren e Toury Emmanuel Shechter Jean-Claude Legrand 《BBA》1988,936(3):325-331
In this study we have measured, under experimental conditions which maintained efficient coupling, respiratory intensity, respiratory control, oxidative phosphorylation capacity and protonmotive force. Succinate cytochrome-c reductase and cytochrome-c oxidase activities were also studied. These investigations were carried out using kidney mitochondria from cyclosporine-treated rats (in vivo studies) and from untreated rats in the presence of cyclosporine (in vitro studies). Inhibition of respiratory intensity by cyclosporine did not exceed 21.1% in vitro and 15.9% in vivo. Since there was no in vitro inhibition of succinate cytochrome-c reductase and cytochrome-c oxidase activities, the slowing of electron flow observed can be interpreted as a consequence of an effect produced by cyclosporine between cytochromes b and c1. Cyclosporine had no effect on respiratory control either in vitro or in vivo. Statistically significant inhibition of the oxidative phosphorylation was observed both in vitro (6.6%) and in vivo (12.1%). Moreover, cyclosporine did not induce any change of membrane potential either in vivo or in vitro. Our findings show that cyclosporine is neither a protonophore, nor a potassium ionophore. In cyclosporine-treated rats we noticed a decrease of protein in subcellular fraction, including the mitochondrial fraction. The role of the inhibition respiratory characteristics by cyclosporine in nephrotoxicity in vivo must take account of these two parameters: inhibition of the respiratory characteristics measured in vitro and diminution of mitochondrial protein in cyclosporine-treated rats. 相似文献
8.
A retrospective study of disease and mortality in zebra finches 总被引:1,自引:0,他引:1
Few published reports exist describing morbidity and mortality in domestic zebra finch colonies maintained in a laboratory animal setting. A retrospective study of clinical disease and mortality in quarantined adult zebra finches was performed. Animals were observed during the 2 week quarantine period and for at least 1 month afterwards (42 days). Signs of disease, including feather and beak abnormalities, oculonasal discharge, increased respiratory rate or stridor, abdominal enlargement, pasty vent, diarrhea, lameness and pectoral muscle loss, were evaluated in our colony during this time. History, physical examination, laboratory testing and postmortem evaluation were used to determine causes of clinical disease. Common clinical findings in sick finches included sudden death, ruffled feathers, increased respiratory rate or gape mouthed breathing, pasty vent or frank diarrhea, and beak discoloration. Organisms frequently isolated were Staphylococcus spp., E. coli, Enterobacter spp., and Coccidia spp. Of the finches that died while in the colony (29.5%), 23.0% died in the first week after arrival. Pathogens frequently isolated from tissues cultured at necropsy included: E. coli, Staphylococcus aureus, Enterobacter spp., and Candida albicans. When observed, pathological lesions consisted of air sacculitis, fibrinopurulent polyserositis and ventriculitis. 相似文献
9.
Cardiac glycoside transport was investigated on the organ and whole plant level. Uptake experiments were carried out with shoot and root cultures of Digitalis lanata. In both systems primary cardenolides, i.e., those with a terminal glucose in their oligosaccharide side chain, were taken up against their concentration gradient, whereas the glucose-free secondary cardenolides were not. Active uptake of primary cardenolides was further evidenced by KCN inhibition of uptake. Using plantlets grown in vitro the long-distance transport of primary cardenolides from the leaves to the roots was demonstrated. Cardenolides were also detected in etiolated leaves, induced on plants with green leaves, which are supposed to be unable to synthezise cardenolides de novo, providing further evidence for long-distance transport. Several primary cardenolides were detected in the honeydew excreted by aphids fed on Digitalis lanata leaves, indicating that the phloem is a transporting tissue for cardenolides. On the other hand, the xylem sap obtained by applying the pressure-chamber technique was cardenolide-free. It was concluded that in Digitalis primary cardenolides serve as both the transport and the storage form of cardenolides. After their synthesis they are either stored in the vacuoles of the source tissue or loaded into the sieve tubes, from which they are unloaded at other sites where they are trapped in the vacuoles of the respective sink tissue. 相似文献
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