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1.
2.
The effect of focused high energy microwave treatment (MW) on brain concentrations and molecular forms of substance P, neurokinin A, neuropeptide Y, neurotensin, galanin and calcitonin gene-related peptide was investigated. Groups of rats were treated as follows: 1) MW, storage for 60 min at 22°C, 2) Decapitation, storage for 60 min at 22°C, 3) Decapitation, storage for 60 min at 22°C, MW treatment, 4) MW, decapitation, storage for 2 min at 22°C and 5) Decapitation, storage for 2 min at 22°C. Peptide concentrations were in all instances highest in the MW sacrificed groups. MW increased the concentration of intact peptides by rapid inhibition of peptidase activity and increase in peptide solubility/extractability. 相似文献
3.
Summary Isolated cod brain microtubules from the cold-adapted Atlantic cod (Gadus morhua) have previously been shown to be highly detyrosinated, a post-translational modification of tubulin usually found in stable
subsets of microtubules. In this study we found this was not restricted only to isolated brain microtubules. Microtubules
in primary cultures of brain and skin cells were composed of both tyrosinated (Tyr)- and detyrosinated (Glu)-tubulin seen
by immunocytochemistry. Immunoelectron microscopy of isolated microtubules showed that individual microtubules were composed
of a mixture of Tyr- and Glu-tubulin. Leukocytes with extending lamellopodia contained only microtubules stained with the
antibody against Tyr-tubulin, and isolated heart tubulin lacked both Tyr- and Glu-tubulin, suggesting that a relative high
level of detyrosination is a characteristic of most, but not all, cod microtubules. Brain cell microtubules were more resistant
to mitotic inhibitors than skin cell microtubules, but this was not correlated to a difference in detyrosination. Brain and
skin cell microtubules were only partially disassembled when incubated at 0°C. Upon reassembly of microtubules at 12°C, microtubules
were still made of mixtures of Tyr- and Glu-tubulin, indicating that detyrosination of assembled microtubules is rapid and/or
that in cod cells, in contrast to mammalian cells, Glu-tubulin can reassemble to microtubules. Our data show that most cod
microtubules are highly detyrosinated, but this is not the cause of their cold adaptation or drug stability. 相似文献
4.
Carina Ämmälä Krister Bokvist Sheila Galt Patrik Rorsman 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1991,1092(3):347-349
The effects of a photoactivatable (DMNPE-caged) ATP-analogue on ATP-regulated K+-channels (KATP-channel) in mouse pancreatic β-cells were investigated using the inside-out patch configuration of the patch-clamp technique. The caged precursor caused a concentration-dependent reduction of channel activity with a Ki of 17 μM; similar to the 11 μM obtained for standard Mg-ATP. The small difference in the blocking capacity between the precursor and ATP is probably the reason why no change in channel activity was observed upon photolysis of the caged molecule and liberation of ATP. It is suggested that the part of the ATP molecule involved in the blocking reaction of the KATP-channel is not sufficiently protected in DMNPE-caged ATP making this compound unsuitable for studying the rapid kinetics of ATP-induced KATP-channel inhibition. 相似文献
5.
6.
Carina Proença Marisa Freitas Daniela Ribeiro Eduardo F. T. Oliveira Joana L. C. Sousa Sara M. Tomé 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):1216-1228
α-Glucosidase inhibitors are described as the most effective in reducing post-prandial hyperglycaemia (PPHG) from all available anti-diabetic drugs used in the management of type 2 diabetes mellitus. As flavonoids are promising modulators of this enzyme’s activity, a panel of 44 flavonoids, organised in five groups, was screened for their inhibitory activity of α-glucosidase, based on in vitro structure–activity relationship studies. Inhibitory kinetic analysis and molecular docking calculations were also applied for selected compounds. A flavonoid with two catechol groups in A- and B-rings, together with a 3-OH group at C-ring, was the most active, presenting an IC50 much lower than the one found for the most widely prescribed α-glucosidase inhibitor, acarbose. The present work suggests that several of the studied flavonoids have the potential to be used as alternatives for the regulation of PPHG. 相似文献
7.
Recent discovery of 5-hydroxymethylcytosine (5hmC) in genomic DNA raises the question how this sixth base is recognized by cellular proteins. In contrast to the methyl-CpG binding domain (MBD) of MeCP2, we found that the SRA domain of Uhrf1, an essential factor in DNA maintenance methylation, binds 5hmC and 5-methylcytosine containing substrates with similar affinity. Based on the co-crystal structure, we performed molecular dynamics simulations of the SRA:DNA complex with the flipped cytosine base carrying either of these epigenetic modifications. Our data indicate that the SRA binding pocket can accommodate 5hmC and stabilizes the flipped base by hydrogen bond formation with the hydroxyl group. 相似文献
8.
Aline Vieira Santos Anna Carina Antunes e Defaveri Humberto Ribeiro Bizzo Rosane Aguiar da Silva San Gil Alice Sato 《In vitro cellular & developmental biology. Plant》2013,49(4):405-413
Varronia curassavica is cultivated for the production of an essential oil useful in the pharmaceutical industry for its strong anti-inflammatory effect. Despite a growing demand, only a few studies have evaluated alternative sources of obtaining plantlets or ways to increase the yield of essential oil from this species. Therefore, this study aimed to optimize the in vitro multiplication rate and analyze the histochemistry and sesquiterpene production potential of conventionally propagated V. curassavica plants, in vitro shoots, and acclimatized plants derived from in vitro shoots. For axillary bud proliferation, Murashige and Skoog medium was supplemented with 6-benzyladenine and thidiazuron alone or in combination with naphthalene acetic acid. Axillary bud proliferation was obtained from culture of nodal or apical segments on medium containing half-strength Murashige and Skoog salts without growth regulators. After 35 d of culture, an average of five buds developed per explant. Elongation and rooting of shoots also occurred in this medium. After the transfer of rooted plants to ex vitro conditions, 100% of the plantlets survived. Histochemical analysis of leaf tissue showed the presence of lipids, acidic lipids, essential oil, phenols, and flavonoids. The essential oils from conventionally propagated and acclimatized plants were extracted by hydrodistillation and analyzed using gas chromatography. The essential oil from acclimatized plants had a similar profile to that from ex vitro plants, but with a higher concentration of the anti-inflammatory compound alpha-humulene. 相似文献
9.
Camilla Schmidt Morgen Benjamin Rokholm Carina Sj?berg Brixval Camilla Schou Andersen Lise Geisler Andersen Mette Rasmussen Anne-Marie Nybo Andersen Pernille Due Thorkild I. A. S?rensen 《PloS one》2013,8(7)
Background
After the worldwide steep increase in child and adolescent overweight and obesity during the last decades, there is now evidence of a levelling off in the prevalence in many countries in the Western world.Aim
To examine whether there still is a plateau in the prevalence of overweight and obesity in Danish children and adolescents, or whether the prevalence is decreasing or rising again.Methods
The trends in the prevalence rates were based on three data sets providing comparable repeated estimates: 1) the Danish Health Visitors Child Health Database (DHVCHD) with measurements on infant and childhood height and weight from 2002 to 2011 (n up to 39,984), 2) the Danish National Birth Cohort (DNBC) with maternal reports of measured infant and childhood height and weight from 1998 to 2010 (n up to 56,826) and 3) the Danish part of the Health Behaviour in School-aged Children survey (HBSC) with self-reported information on adolescent height and weight from the years 2002 to 2010 (n = 16,557). Overweight and obesity were categorized according to WHO growth standards. Trends were assessed by repeated point estimates and linear regression analyses providing regression coefficients for changes in per cent per year with 95% confidence intervals (CI).Results
The prevalence rates of overweight and obesity for infants, children and adolescents showed a mixed pattern of decline, stability and increase (ranging from -1.10 through 0.29 per cent per year with CI’s from -3.10 through 2.37). Overall, there were no consistent statistically significant trends upwards or downwards, although some significant downward trends in childhood and adolescence were observed.Conclusion
This study, based on data from 1998 through 2011, showed that the prevalence rates of overweight and obesity among Danish infants, children and adolescents were largely still on a plateau with tendencies for a decline among children and adolescents. 相似文献10.
Sam Nordfeldt Teresia ?ngarne-Lindberg Maria Nordwall Joakim Ekberg Carina Berter? 《PloS one》2013,8(6)