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61.
The adsorption of phenols and esters of acid antiseptics by the bacterial cell (Escherichia coli and Staphylococcus aureus) was investigated in relatoin to their toxic effect, and it has been observed that the definite quantity of antiseptics must be adsorbed on the solid phase of the bacterial cell in order to give the definite toxic effect, and the toxic effect is independent of the quantity dissolved in the inner cell fluid or in the lipid phase of the cell. The result shows that the toxic effect of these antiseptics on either bacteria and yeast, is exclusively limited by the adsorbed quantity.

The adsorbed quantity required for the definite toxic effect was nearly the same as that previously observed in the case of the yeast, and the mechanism of the toxic action of these antiseptics was assumed to be same with each other in any case of microbes.  相似文献   
62.
The bacterial growth is inhibited by nitrofurane compounds, although the yeast growth is hardly affected. In relation to the selective toxicity of nitrofuranes for bacteria, the interaction between microbes (Escherichia coli, Staphylococcus aureus and bakers– yeast) and nitrofurane compounds (5-nitro-2-furfural semicarbazone and 5-nitro-2-furylacryl amide) was examined.

Apparently, in the bacterial suspension containing energy substrate, nitrofuranes are continuously reduced to corresponding aminofuranes, respectively. The velocity of the bacterial reduction at the growth inhibiting condition was evaluated as great as above 30 per cent of the limit of supplying velocity of coenzymes in the cell, the reduction velocity of such value is enough to inhibit the bacterial growth, because the electron transfer in the cell metabolism is disordered.

On the other hand, in the yeast suspension, the reduction velocity was negligibly small. The difference of the reduction ability between bacteria and yeast was seemingly owing to the fact that the permeability of the nitrofuranes differs by the kind of microbe so that it was concluded that the antimicrobial effect of nitrofuranes is limited by the permeability for the microbe cell.  相似文献   
63.
A strain of Alcaligenes isolated from soil was a good producer of β-glucuronidase, and the enzyme was purified from the cell-free extract by sequential column chromatography on DEAE-Toyopearl, Toyopearl HW-55F, and Phenyl-Sepharose CL-4B. By these procedures, two β-glucuronidases designated as β-glucuronidases I and II were purified 240- and 508-fold, respectively. β-Glucuronidase I, with a molecular weight of 75,000, had an optimum pH at 7.5 and the enzyme II, with a molecular weight of 300,000, had maximum activity at pH 6.0. Both enzymes were strongly inhibited by saccharo-1,4-lactone, glucaro-δ-lactam, p-chloromercuribenzoate, Hg2+, and N-bromosuccinimide. β-Glucuronidase I was active toward estrogen-3-β-glucuronides and inert toward β-glucuronide conjugates of menthol, estrogen-17β-, estrogen-16α-, androsterone-3α-, testosterone-17β-, cortisol-17α-. β-Glucuronidase II hydrolyzed all of these substrates. β-Glucuronidase I was inhibited by phenolphthalein and its glucuronide.  相似文献   
64.
Intracellular lipase of the fungus Sclerotina Libertiana Fcl. could be formed powerfully by washed mycelium during shaking in a plain buffer solution, just as well as in the case of shaking culture. Experiments showed revealed it to be favourable to set the mycelium in the experiment harvested at the end of its stationary phase of growth, and that the addition of various respiratory carbon sources had inhibiting effects, while several surface active agents and some enzyme preparations accelerating effects on the lipase formation. Also, the quality and the quantity of consumed cell-materials in the shaking experiment were investigated in relation to lipase formation.  相似文献   
65.
By using the purified phospholipase A and B of Sclerotinia Libertiana Fcl., enzymic degradation of soy-lecithin was investigated. From the paperchromatography experiments, it was concluded that the phospholipase A specifically hydrolyzes the ester linkage of unsaturated fatty acid of soy-lecithin whereas the phospholipase B hydrolyzes the linkage of saturated acid of soy-lysolecithin. Phospholipase B also could hydrolyze the two fatty acids from the soy-lecithin, however, the hydrolysis rate was rather inhibited by combination with the phospholipase A. Moreover, the phospholipase B activity on soy-lecithin and soy-lysolecithin was found to be increased by the presence of soy-lecithin and soy-lysolecithin in the reaction mixture, and to be inhibited by the addition of Tween 20.  相似文献   
66.
“Isosclerotan”, a polysaccharide constituent extracted with a sodium hydroxide solution from sclerotia of Sclerotinia libertiana, could be purified by the successive precipitation with the followings; a mixture of copper sulfate and sodium hydroxide, ammonium sulfate, and ethyl alcohol. The preparation proved homogeneous by ultracentrifugal analysis. From sedimentation and viscosity measurements, the molecular weight of isosclerotan was calculated as 6.13 × 106, andas 1.60 × 105 after treatment with a dilute oxalic acid solution. Isosclerotan was scarecely soluble in cold water but soluble in hot water, yielding a highly viscous solution. It exhibited a low positive optical rotation, + 23.0° (in water), and infrared spectrum had a sharp absorption at 890~898 cm?1, which indicated the prevalence of the β-glycosidic linkage in isosclerotan. Through degradation by acids and enzymes of isosclerotan, there were obtained various oligosaccharides containing β-1.3, β-1.4, and β-1.6 linkages. From results obtained by periodate oxidation and methylation, it is assumed that the polysaccharide involves the 1.3, 1.4, and 1.6 linkages in 47.7%, 16.6% and 35.7%, respectively, and a branching structure about 12.5%.  相似文献   
67.
Like other CNS neurons, mature retinal ganglion cells (RGCs) are unable to regenerate their axons after nerve injury due to a diminished intrinsic regenerative capacity. One of the reasons why they lose the capacity for axon regeneration seems to be associated with a dramatic shift in RGCs’ program of gene expression by epigenetic modulation. We recently reported that (1R)-isoPropyloxygenipin (IPRG001), a genipin derivative, has both neuroprotective and neurite outgrowth activities in murine RGC-5 retinal precursor cells. These effects were both mediated by nitric oxide (NO)/S-nitrosylation signaling. Neuritogenic activity was mediated by S-nitrosylation of histone deacetylase-2 (HDAC2), which subsequently induced retinoic acid receptor β (RARβ) expression via chromatin remodeling in vitro. RARβ plays important roles of neural growth and differentiation in development. However, the role of RARβ expression during adult rat optic nerve regeneration is not clear. In the present study, we extended this hypothesis to examine optic nerve regeneration by IPRG001 in adult rat RGCs in vivo. We found a correlation between RARβ expression and neurite outgrowth with age in the developing rat retina. Moreover, we found that IPRG001 significantly induced RARβ expression in adult rat RGCs through the S-nitrosylation of HDAC2 processing mechanism. Concomitant with RARβ expression, adult rat RGCs displayed a regenerative capacity for optic axons in vivo by IPRG001 treatment. These neuritogenic effects of IPRG001 were specifically suppressed by siRNA for RARβ. Thus, the dual neuroprotective and neuritogenic actions of genipin via S-nitrosylation might offer a powerful therapeutic tool for the treatment of RGC degenerative disorders.  相似文献   
68.

Background

Earlier studies implicated norepinephrine transporter (NET) gene (SLC6A2) polymorphisms in the etiology of major depressive disorder (MDD). Recently, two single nucleotide SLC6A2 polymorphisms, G1287A in exon 9 and T-182C in the promoter region, were found to be associated with MDD in different populations. We investigated the relationship between the brain volume and these two polymorphisms of the SLC6A2 in MDD patients.

Methods

We obtained 3D high-resolution T1-weighted images of 30 first-episode MDD patients and 48 age- and sex-matched healthy subjects (HS). All were divided into 4 groups based on polymorphism of either the G1287A or the T-182C genotype. VBM analysis examined the effects of diagnosis, genotype, and genotype-diagnosis interactions.

Results

Diagnosis effects on the brain morphology were found in the left superior temporal cortex. No significant genotype effects were found in the T-182C and the G1287A. A significant genotype (G1287A)–diagnosis interaction was found in the left dorsolateral prefrontal cortex. No significant genotype (T-182C)–diagnosis interaction effects were observed in any brain region.

Conclusions

In MDD patients there seems to be a relationship between the volume of the dorsolateral prefrontal cortex and polymorphism of the SLC6A2 G1287A gene.  相似文献   
69.
70.
During the collection phase of the dried blood spot method, practitioners need to ensure that there is no smearing of the blood sample on the filter paper or else readings from it will be invalid. This can be difficult to accomplish in the field if there is relative motion between the site of blood discharge on the finger and the filter paper. In this article, a gyroscope stabilization method is introduced and demonstrated to provide consistent and improved dried blood spot collection within a circular guide region notwithstanding the presence of rocking.  相似文献   
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