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141.
Mumps virus (MuV) strains isolated in Saitama Prefecture, Japan, from 1997 to 2001, were examined by analyzing the SH and the F gene nucleotide sequences. The results of the SH gene analysis showed that only genotype G was found in 2001 as well as in 2000, and that genotype J, which we proposed as a new genotype in a previous study, was from a different lineage than the genotype J described by Tecle et al. (J. Gen. Virol. 82, 2675-2680). We therefore, propose to rename the genotype as K to avoid confusion. Then, the F gene of genotypes G, H, and K strains were analyzed together with previously reported strains in this study. The results of phylogenetic analysis of the F gene nucleotide sequences showed that these strains formed a cluster as described by the SH gene analysis. Alignment of the F amino acid sequences showed that the F protein was well conserved among strains of different genotypes with a few amino acid differences. These results provide better information for the characterization of contemporary MuV strains in Japan.  相似文献   
142.
A cell line with the characteristics of hepatocytes was established from rat early embryonic stem cells (REES). This cell line was established using a new novel method of Ishiwata et al. from two cell embryos taken from the spontaneous dwarf rat (SDR). The hepatocyte cell line (REES-hep) was instituted from dark red colored tissue in embryos during embryogenesis using REES cell line cultured in the presence of embryotrophic factors. These cell lines were cultured with DMEM/F12 medium supplemented 10% FBS and 1 ng/ml of LIF. They were found to maintain their diploid state, were characterized with 42 normal chromosomes and proliferated to confluence; contact inhibition was also present. These cells produced albumin when cultured using a collagen sponge gel system and reconstructed in a funicular form resembling the cell cords of liver. The cells also produced albumin and bilirubin when transplanted into the spleen of SDR Reconstruction of a REES-hep cell line from early embryonic stem cells should help in treating hepatic insufficient patients. It will be valuable for further research, as an introduction to cell transplantation and application for use in a bio-hybrid typed liver apparatus.  相似文献   
143.
The identification and quantification of N(epsilon)-(hexanoyl)lysine (N(epsilon)-HEL), which was found from the reactions between lipid hydroperoxide and lysine, from human urine was examined using liquid chromatography/tandem mass spectrometry (LC/MS/MS). The N(epsilon)-HEL in the partially purified urine fraction was identified using LC/MS/MS by several approaches including precursor/product ion scans. The peak found by the multiple-reaction monitoring (MRM) of the collision-induced fragmentation of N(epsilon)-HEL was clearly observed in urine, and the elution position coincided with the synthetic standard N(epsilon)-HEL. The product, estimated N(epsilon)-HEL, was absorbed by a specific antibody to N(epsilon)-HEL. Moreover, N(alpha)-HEL, one of the plausible hexanoyl adducts from the reaction between the N(alpha) moiety of L-lysine and the peroxidized lipid, was hardly detected in urine samples, suggesting that the origin of the N(epsilon)-HEL is the peroxidized lipid-modified proteins but not artificial hexanoylated L-lysine. Using the MRM technique, the amount of urinary N(epsilon)-HEL from the control subjects (observed healthy) was estimated to be 1.58 +/- 0.23 mumol/mol of creatinine. A comparative study of the urinary N(epsilon)-HEL with an oxidative stress marker, 8-oxo-7,8-dihydro-2'-deoxyguanosine, showed a high correlation (r = 0.844) between the two biomarkers. Furthermore, the quantification of N(epsilon)-HEL in the control and diabetic urines revealed that the urinary N(epsilon)-HEL from diabetic subjects (3.21 +/- 0.65 mumol/mol of creatinine) was significantly higher than that from the control subjects.  相似文献   
144.
Several 2-alkoxycarbonyltrifluoromethanesulfonanilides were prepared to examine their miticidal activity. 4-Halo-2-alkoxycarbonyltrifluoromethanesulfonanilides in particular showed good miticidal activity against Tyrophagus putrescentiae (Tp), Dermatophagoides farinae (Dp) and Chelacaropsis moorei (Cm). Amidoflumet (methyl 5-chloro-2-[(trifluoromethyl)sulfonyl]aminobenzoate) was selected and has been developed as a new miticide for house dust mites.  相似文献   
145.
We cloned and characterized the gene and cDNA of Aspergillus oryzae cytochrome P450nor (Anor). The Anor gene (nicA; CYP55A5) has a different gene structure from other P450nor genes in that it has an extra intron. There were not only two kinds of mRNA but also two sets of TATA-box and CCAAT-box, and it appears that this gene has two expression patterns, like CYP55A1 of Fusarium oxysporum. A reporter analysis using the uidA gene indicated that gene expression of CYP55A5 was induced under anaerobic conditions, like CYP55A1. When the CYP55A5 gene was overexpressed in A. oryzae, a large amount of active Anor were accumulated as intracellular protein. Anor employed both NADH and NADPH as electron donors for reducing nitric oxide to nitrous oxide. Anor measured the amount of NO generated from 3-(2-Hydroxy-1-(1-methylethyl)-2-nitrosohydrazino)-1-propanamine (NOC5) with a spectrophotometer. The sensitivity was 10 nmol/ml.  相似文献   
146.
A novel protein overexpression system of Aspergillus oryzae was constructed. Five promoters which originate from A. oryzae expressed sequence tag (EST) clones in submerged culture were obtained by genome walking. These were subjected to beta-glucuronidase (GUS) reporter assays. The promoter of manganese superoxide dismutase-encoding gene (sodM) showed the most GUS production. The sodM gene was abundantly expressed in submerged culture but little expressed in solid-state culture. The sodM promoter was approximately 3-fold induced by the addition of 0.01% H2O2. Glucoamylase production in A. oryzae using the sodM promoter led to secretion of approximately 1 g/l-broth in Czapek-Dox medium for 3 d. Fucose lectin production in A. oryzae using the sodM promoter led to overexpression as a specific and abundant intracellular protein.  相似文献   
147.
Serratia marcescens mutants defective in production of the red pigment prodigiosin and the biosurfactant serrawettin W1 in parallel were isolated by transposon mutagenesis of strain 274. Cloning of the DNA fragment required for production of these secondary metabolites with different chemical structures pointed out a novel open reading frame (ORF) named pswP. The putative product PswP (230 aa) has the distinct signature sequence consensus among members of phosphopantetheinyl transferase (PPTase) which phosphopantetheinylates peptidyl carrier protein (PCP) mostly integrated in the nonribosomal peptide synthetases (NRPSs) system. Since serrawettin W1 belongs to the cyclodepsipeptides, which are biosynthesized through the NRPSs system, and one pyrrole ring in prodigiosin has been reported as a derivative of L -proline tethered to phosphopantetheinylated PCP, the mutation in the single gene pswP seems responsible for parallel failure in production of prodigiosin and serrawettin W1.  相似文献   
148.
Intra-aortic measurement of nitric oxide (NO) would provide valuable insights into NO bioavailability in systemic circulation and vascular endothelial function. In the present study, we thus developed a catheter-type NO sensor to measure intra-aortic NO concentration in vivo. An NO sensor was encased and fixed in a 4-Fr catheter. The sensor was then located in the thoracic aorta via the femoral artery through a 7-Fr catheter to measure intra-aortic plasma NO concentration in vivo in anesthetized dogs. Infusion of acetylcholine (10 microg/kg) increased base-to-peak plasma NO level in the aorta by 2.4+/-0.4 nM (n=7). After 20-min infusion of N(G)-methyl-L-arginine (NO synthase inhibitor), changes in plasma NO concentration in response to acetylcholine were attenuated significantly (1.8+/-0.4 nM, P<0.003, n=7). In conclusion, the newly developed catheter-type NO sensor successfully measured acetylcholine-induced changes in intra-aortic plasma concentration of endothelium-derived NO in vivo and demonstrated applicability to direct evaluation of intravascular NO bioavailability.  相似文献   
149.
Although cardioviruses related to Theiler's murine encephalomyelitis virus (TMEV) appear to be common in mice and rats, few TMEV isolates have been obtained from rat colonies. In 1991, a cardiovirus isolate designated NGS910 was obtained from sentinel rats exposed to cage bedding previously used by adult rats that were TMEV seropositive, but had never manifested clinical signs of disease. To determine to which group and subgroup of cardiovirus this virus belongs, the sequence of the viral genome was determined. The NGS910 genome consisted of 8,021 nucleotides and the 5'-nontranslated region had a predicted secondary structure that is similar to members of the TMEV group of cardioviruses. The Leader-P3D open reading frame (L ORF) of NGS910 had strong homology with L ORFs of other TMEVs (72% identity), but lower homology with EMCV cardioviruses (55 to 56%). Phylogenetic analyses on the basis of aligned nucleotide sequences of the L ORF (6,924 b) and the internal L* ORF (471 b) supported this classification of NGS910 as a TMEV strain. However, within the TMEV group, NGS910 wassufficiently divergent from other isolates that it could not be regarded as simply a mutant strain of a known TMEV. As genetic distances between NGS910 and other TMEVs were greater than those between Mengo virus of EMCV and other EMCVs, we propose to designate the NGS910 isolate as a rat Theiler-like virus.  相似文献   
150.
Transgenic mouse technology has been very valuable for the study of lens fiber cells since they can not be propagated in cell culture. The targeting of transgenes to the lens has traditionally been done with the A-crystallin promoter. However, while lens-specific, transgenic lines made with the A-crystallin promoter express the transgene at levels 100–300-fold lower than endogenous A-crystallin. Here we propose an alternative, the chicken B1-crystallin promoter (–432/+30). Transgenic mice made with this promoter have successfully expressed CAT, d/n m-calpain, Wee1, and B2-crystallin mRNA at levels comparable to the endogenous B1-crystallin gene and no eye abnormalities such as cataracts, have resulted. All of the transgenic lines made with the chicken B1-crystallin promoter have expressed the transgene in the lens fiber cells, and the best lines express at levels close to endogenous B1-crystallin. While RNA expression is very high, only moderate protein expression has been achieved, implying that the high protein expression of the crystallins is partially controlled at the level of translation. Thus, the chicken B1-crystallin promoter directs high level RNA expression to lens fiber cells, which may be especially useful for the expression of ribozyme and anti-sense RNAs in addition to ectopic proteins.  相似文献   
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