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81.
Lee JB Yamagishi C Hayashi K Hayashi T 《Bioscience, biotechnology, and biochemistry》2011,75(3):459-465
Three antiviral and immunostimulating substances (LC1, LC2 and LC3) were isolated from a hot water extract of seeds of Pimpinella anisum by combination of anion-exchange, gel filtration and hydrophobic interaction column chromatographies. Chemical and spectroscopic analyses revealed them to be lignin-carbohydrate-protein complexes. These lignin-carbohydrate complexes (LCs) showed antiviral activities against herpes simplex virus types 1 and 2 (HSV-1 and -2), human cytomegalovirus (HCMV) and measles virus. LCs were also found to interfere with virus adsorption to the host cell surface and directly inactivate viruses. Furthermore, they enhanced nitric oxide (NO) production by inducing iNOS mRNA and protein expression in RAW 264.7 murine macrophage cells. The induced mRNA expression of cytokines including IL-1β and IL-10 was also apparent. These results suggest that the lignin-carbohydrate-protein complexes from P. anisum possessed potency as functional food ingredients against infectious diseases. 相似文献
82.
Kaku T Matsunaga N Ojida A Tanaka T Hara T Yamaoka M Kusaka M Tasaka A 《Bioorganic & medicinal chemistry》2011,19(5):1751-1770
A novel series of naphthylmethylimidazole derivatives and related compounds have been investigated as selective 17,20-lyase inhibitors. Optimization of the substituent at the 6-position on the naphthalene ring was performed to yield a methylcarbamoyl derivative, which exhibited potent inhibitory activity against human 17,20-lyase and promising selectivity (>200-fold) for 17,20-lyase over CYP3A4. Further modifications of the methylcarbamoyl derivative led to the discovery of the corresponding tricyclic compound, which showed highly potent activity against human 17,20-lyase (IC(50) 19 nM) and good selectivity (>1000-fold) for inhibition of 17,20-lyase over CYP3A4. Additional biological evaluation revealed that the tricyclic compound had potent in vivo efficacy in monkeys and favorable pharmacokinetic profiles when administered in rats. Asymmetric synthesis of the selective tricyclic inhibitor was also achieved using a chiral α-hydroxy ketone. 相似文献
83.
A novel thermoresponsive aqueous antithrombogenic coating material comprising a heparin bioconjugate with a six-branched, star-shaped poly(2-(dimethylaminoethyl)methacrylate) (6B-PDMAEMA), which has both thermoresponsive and cationic characters, was developed to reduce the thrombogenic potential of blood-contacting materials such as synthetic polymers or tissue-engineered tissues in cardiovascular devices. 6B-PDMAEMA with M(n) of ca. 24 kDa was designed as a prototype compound by initiator-transfer agent-terminator (iniferter)-based living radical photopolymerization from hexakis(N,N-diethyldithiocarbamylmethyl)benzene. Bioconjugation of heparin with 6B-PDMAEMA occurred as soon as both aqueous solutions were simply mixed to form particles. The particle size at 25 °C was less than several hundred nanometers in diameter under a heparin/6B-PDMAEMA mixing weight ratio of over 2.5. The particles were very stable because of the prevention of hydrolysis of 6B-PDMAEMA in its bioconjugated form. Because the lower critical solution temperature of the bioconjugate ranges from approximately 20 to 36 °C for the formation of microparticles, the coating could be done in an aqueous solution at low temperatures. The excellent adsorptivity and high durability of the coating above 37 °C was demonstrated on silicone and polyethylene films by surface chemical compositional analysis. Blood coagulation was significantly reduced on the bioconjugate-coated surfaces. Therefore, the thermoresponsive bioconjugate developed here appears to satisfy the initial requirements for a biocompatible aqueous coating material. 相似文献
84.
Yamada Y Yamada K Nomura N Yamano A Kimura R Naiki M Fukushi D Wakamatsu N Taniguchi A Yamaoka N Kaneko K Fujimori S 《Nucleosides, nucleotides & nucleic acids》2011,30(12):1272-1275
Mutations of two enzyme genes, HPRT1 encoding hypoxanthine guanine phosphoribosyltransferase (HPRT) and PRPS1 encoding a catalytic subunit (PRS-I) of phosphoribosylpyrophosphate synthetase, cause X-linked inborn errors of purine metabolism. Analyzing these two genes, we have identified three HPRT1 mutations in Lesch-Nyhan families following our last report. One of them, a new mutation involving the deletion of 4224 bp from intron 4 to intron 5 and the insertion of an unknown 28 bp, has been identified. This mutation resulted in an enzyme polypeptide with six amino acids deleted due to abnormal mRNA skipping exon 5. The other HPRT1 mutations, a single base deletion (548delT, 183fs189X), and a point mutation causing a splicing error (532+1G>A, 163fs165X) were detected first in Japanese patients but have been reported in European families. On the other hand, in the analysis of PRPS1, no mutation was identified in any patient. 相似文献
85.
Yamaoka N Inazawa K Inagawa S Yasuda M Mawatari K Nakagomi K Fujimori S Yamada Y Kaneko K 《Nucleosides, nucleotides & nucleic acids》2011,30(12):1256-1259
Genetic mutations in the purine salvage enzyme, hypoxanthine-guanine phosphoribosyltransferase (HPRT), are known to cause Lesch-Nyhan syndrome and Kelley-Seegmiller syndrome. In patients, purine metabolism is different from that of normal persons. We have previously developed a method for simultaneously determining the concentration of purine and pyrimidine nucleosides and nucleotides. This system was applied to determine the concentrations of nucleosides and nucleotides in HPRT-deficient cell lines. The amount of inosine 5'-monophosphate (IMP) was different in Lesch-Nyhan syndrome, Kelley-Seegmiller syndrome, and control cell lines. The difference in the amount of IMP confirmed the mutation of the enzyme. 相似文献
86.
Ishizuka T Hess RA Reuter B Federico MS Yamada Y 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(7):1905-1910
Health and fitness professionals working with athletes could establish effective and safe practice and training programs if recovery time on dynamic balance from exertion was available. Research investigating the time needed to recover dynamic limits of stability (LOS) from exertion has not been reported. The purpose of this study was to determine the recovery timeline on LOS from functional fatigue in collegiate athletes. Eighteen athletes (11 men, 7 women) from Division II collegiate soccer team who passed prescreening tests to identify their fitness levels were randomly tested on 2 different days by condition (fatigue or nonfatigue). Functional fatigue was determined by using the Borg 15-point rating of perceived exertion (RPE) scale. Subjects were tested on LOS on the Biodex Balance System pre, post, 10, 15, and 20 minutes for each condition. The main effect for condition was not significant (F() = 0.004, p = 0.948), whereas the main effect for time was significant (F(4,64) = 6.167, p < 0.001). The RPE scoring revealed the significant main effect in FATIGUE (F(2.69, 45.73) = 234.8, p < 0.001). In conclusion, 20 minutes of functional activity will likely have a negative influence on dynamic balance, with balance recovery occurring within 10 minutes after the cessation of exercise in Division II collegiate soccer athletes. Moreover, the level of exertion measured by RPE would correspond to athletes' ability to control their center of mass. 相似文献
87.
Odaka K Aoki I Moriya J Tateno K Tadokoro H Kershaw J Minamino T Irie T Fukumura T Komuro I Saga T 《PloS one》2011,6(10):e25487
Background
Transplantation of mononuclear cells (MNCs) has previously been tested as a method to induce therapeutic angiogenesis to treat limb ischemia in clinical trials. Non-invasive high resolution imaging is required to track the cells and evaluate clinical relevance after cell transplantation. The hypothesis that MRI can provide in vivo detection and long-term observation of MNCs labeled with manganese contrast-agent was investigated in ischemic rat legs.Methods and Findings
The Mn-labeled MNCs were evaluated using 7-tesla high-field magnetic resonance imaging (MRI). Intramuscular transplanted Mn-labeled MNCs were visualized with MRI for at least 7 and up to 21 days after transplantation in the ischemic leg. The distribution of Mn-labeled MNCs was similar to that of 111In-labeled MNCs measured with single-photon emission computed tomography (SPECT) and DiI-dyed MNCs with fluorescence microscopy. In addition, at 1–2 days after transplantation the volume of the site injected with intact Mn-labeled MNCs was significantly larger than that injected with dead MNCs, although the dead Mn-labeled MNCs were also found for approximately 2 weeks in the ischemic legs. The area covered by CD31-positive cells (as a marker of capillary endothelial cells) in the intact Mn-MNCs implanted site at 43 days was significantly larger than that at a site implanted with dead Mn-MNCs.Conclusions
The present Mn-enhanced MRI method enabled visualization of the transplanted area with a 150–175 µm in-plane spatial resolution and allowed the migration of labeled-MNCs to be observed for long periods in the same subject. After further optimization, MRI-based Mn-enhanced cell-tracking could be a useful technique for evaluation of cell therapy both in research and clinical applications. 相似文献88.
The reversing-pulse electric birefringence (RPEB) technique was applied to the study of the temperature effect on the electrooptical and hydrodynamic properties of a fractionated [Glu(OBzl)]n sample, which is molecularly dissolved in cyclohexanone. The aim was to develop a standard analytical method for thermal denaturation and temperature-induced conformational transitions. The field-on reverse and steady-state signal, and the field-off decay signal, were measured at 535 nm and at a constant low field strength (ca. 3 kV/cm) over a wide temperature range (5–90°C). The steady-state birefringence and the relaxation time in the decay process were also measured at two constant temperatures (5 and 70°C) over a wide field strength range (E ≤ 20 kV/cm). By the combination of these two different sets of RPEB measurements, the unwanted effect of the high pulse field on polymer conformation at elevated temperatures could be minimized. Together with the density and viscosity of cyclohexanone measured between 5 and 95°C, the following quantities could be evaluated: the weight-average permanent dipole moment and polarizability anisotropy, the reduced optical anisotropy factor (Δg/n), the weight-average length, and the degree of polydispersity. All these quantities, except for Δg/n, were found to be almost independent of temperature (5–90°C) and concentration (1.54–4.27 mM). 相似文献
89.
Esterification of Escherichia coli tRNAs with D-histidine and D-lysine by aminoacyl-tRNA synthetases
Takayama T Ogawa T Hidaka M Shimizu Y Ueda T Masaki H 《Bioscience, biotechnology, and biochemistry》2005,69(5):1040-1041
It is generally believed that only L-amino acids are acceptable in protein synthesis, though some D-amino acids, including D-tyrosine, D-aspartate, and D-tryptophan are known to be bound enzymatically to tRNAs. In this report, we newly show that D-histidine and D-lysine are also able to be the substrates of respective Escherichia coli aminoacyl-tRNA synthetases. 相似文献
90.
Evaluation of dynamic features of Escherichia coli 16S ribosomal RNA in homogeneous physiological solution
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Sakamoto T Mahara A Yamagata K Iwase R Yamaoka T Murakami A 《Biophysical journal》2005,89(6):4122-4128
There is no methodology for the estimation of the dynamic features of large-molecular-weight RNAs in homogeneous physiological media. In this report, a luminescence anisotropy-based method using a long-lifetime luminescent oligonucleotide probe for the estimation of the dynamic features of large-molecular-weight RNA is described. As a luminescent probe, Ru(II) complex-labeled oligonucleotides, which have a complementary sequence to the single-stranded regions of Escherichia coli 16S rRNA, were synthesized. After the hybridization of the probe to single-stranded regions of 16S rRNA, the segmental motions of the regions were evaluated by time-resolved luminescence anisotropy analysis. In 16S rRNA, the L2 site (323-332 nt) was found to be the most flexible among the seven sites chosen. From a comparison between the hybridization kinetics of oligonucleotides to these single-stranded regions and the rotational correlation times, it was suggested that the flexibility of the single-stranded region was closely correlated with the hybridization kinetics. Furthermore, results of the luminescence lifetime measurement and luminescence quenching experiments suggested that the highly flexible region was located on the surface of the 16S rRNA and that the less flexible region was located in the depths of 16S rRNA. 相似文献