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101.
Coenzyme Q (CoQ) is an endogenous enzyme cofactor that may provide protective benefits as an antioxidant. In this study, in order to determine whether the concentrations of CoQ(9) are associated with the oxidative status in vivo, the effects of dietary supplements of CoQ(9) on mice were evaluated by using a new biomarker, total hydroxyoctadecadienoic acid (tHODE). Biological samples were first reduced and then saponified to convert the various oxidation products of linoleates to tHODE. Subsequently, by using GC-MS analyses, we simultaneously determined the absolute concentration of tHODE; its stereoisomer ratio, 9- and 13-(Z,E)-HODE/9- and 13-(E,E)-HODE, which is a measure of the hydrogen donor capacity of antioxidants; and the concentration of 8-iso-prostaglandin F(2alpha) (8-iso-PGF(2alpha)). Remarkable decreases in tHODE and 8-iso-PGF(2alpha) levels were observed in the plasma, erythrocytes, liver, and brain of mice that were maintained for 1 month on an alpha-tocopherol (alphaT)-free (E-free) diet supplemented with ubiquinone-9 (Q(9); 0.04 wt.%) as compared to those of mice that were fed an E-free diet. The (Z,E/E,E) HODE ratio was increased in the plasma and erythrocytes of mice that were fed a Q(9)-fortified diet as compared to those that were fed an E-free diet. In particular, the (Z,E/E,E) HODE ratios in the plasma and brain were significantly correlated with the concentrations of ubiquinol-9 (Q(9)H(2)). Further, the liver and brain levels of tHODE and 8-iso-PGF(2alpha) were significantly correlated with the plasma and erythrocyte levels of tHODE and 8-iso-PGF(2alpha), respectively, and in some cases, also exhibited significant correlations with antioxidants. These results indicate that the plasma and erythrocyte levels of tHODE and its stereoisomeric ratio can be prominent biomarkers for the evaluation of the oxidative status and antioxidant capacity in vivo, including in the liver and brain, and that CoQ plays a major role in the in vivo antioxidant network.  相似文献   
102.
Growth and differentiation factor 5 (GDF-5) is a homodimeric protein stabilized by a single disulfide bridge between cysteine 465 in the respective monomers, as well as by three intramolecular cysteine bridges within each subunit. A mature recombinant human GDF-5 variant with cysteine 465 replaced by alanine (rhGDF-5 C465A) was expressed in E. coli, purified to homogeneity, and chemically renatured. Biochemical analysis showed that this procedure eliminated the sole interchain disulfide bond. Surprisingly, the monomeric variant of rhGDF-5 is as potent in vitro as the dimeric form. This could be confirmed by alkaline phosphatase assays and Smad reporter gene activation. Furthermore, dimeric and monomeric rhGDF-5 show comparable binding to their specific type I receptor, BRIb. Studies on living cells showed that both the dimeric and monomeric rhGDF-5 induce homomeric BRIb and heteromeric BRIb/BRII oligomers. Our results suggest that rhGDF-5 C465A has the same biological activity as rhGDF-5 with respect to binding to, oligomerization of and signaling through the BMP receptor type Ib.  相似文献   
103.
Several geometrical isomers of 3,13- and 2,13-octadecadien-1-ols and their acetates were synthesized starting from 1,8-octanediol or 1,9-nonanediol utilizing acetylene coupling reactions. In addition to commercially available compounds, all geometrical isomers of each dienyl compound were analyzed by NMR and GC-MS to accumulate chemical data for studies of sex pheromones secreted from clearwing moths classified into the family Sesiidae of Lepidoptera. Although acetoxy derivatives of the 3,13- and 2,13-dienes showed almost the same mass spectra, the alcohols were distinguished by comparing the relative intensities of [M-18](+) at m/z 248, indicating direct differentiation of the two positional isomers without derivatization. Furthermore, each geometrical isomer eluted from a high-polar GC column with a different retention time. Base on these data, a pheromone gland extract of a sesiid moth, Nokona pernix, was analyzed by GC-EAD and GC-MS, and two EAG-active components were identified, viz., the (3E,13Z)- and (3Z,13Z)-isomers of 3,13-octadecadien-1-ol in a ratio of 9:1. In the field, the synthetic compounds mixed in 9:1 ratio attracted N. pernix males well, while a single component scarcely attracted the males. The number of attracted males peaked in the middle of June, and a small second peak was observed in August.  相似文献   
104.
Increasing syphilis incidence among men who have sex with men (MSM) has been reported. The index case was a human immunodeficiency virus type 1 (HIV-1)-positive MSM who presented coincidentally with the secondary syphilis and a rebound of plasma viral load after complete suppression of HIV-1 (below 50 copies/ml) for 13 months with potent antiretroviral therapy (PART), suggesting a possibility of HIV-1 superinfection. We analyzed HIV-1 sequences before and after syphilis in four HIV-1-positive patients including the index case to explore drug resistance mutations (DRMs) and a possibility of HIV-1 superinfection. There were patients who obtained DRMs around syphilis infection but no evidence of HIV-1 superinfection was obtained. Our results underline the importance of strict adherence to PART.  相似文献   
105.
To screen for glycoproteins showing aberrant sialylation patterns in sera of cancer patients and apply such information for biomarker identification, we performed SELDI‐TOF MS analysis coupled with lectin‐coupled ProteinChip arrays (Jacalin or SNA) using sera obtained from lung cancer patients and control individuals. Our approach consisted of three processes (i) removal of 14 abundant proteins in serum, (ii) enrichment of glycoproteins with lectin‐coupled ProteinChip arrays, and (iii) SELDI‐TOF MS analysis with acidic glycoprotein‐compatible matrix. We identified 41 protein peaks showing significant differences (p<0.05) in the peak levels between the cancer and control groups using the Jacalin‐ and SNA‐ProteinChips. Among them, we identified loss of Neu5Ac (α2,6) Gal/GalNAc structure in apolipoprotein C‐III (apoC‐III) in cancer patients through subsequent MALDI‐QIT‐TOF MS/MS. Furthermore, subsequent validation experiments using an additional set of 60 lung adenocarcinoma patients and 30 normal controls demonstrated that there is a higher frequency of serum apoC‐III with loss of α2,6‐linkage Neu5Ac residues in lung cancer patients compared to controls. Our results have demonstrated that lectin‐coupled ProteinChip technology allows the high‐throughput and specific recognition of cancer‐associated aberrant glycosylations, and implied a possibility of its applicability to studies on other diseases.  相似文献   
106.
Key Message

Differential expression of mi-RNAs targeting developmental processes and progressive downregulation of repeat-associated siRNAs following genome merger and genome duplication in the context of allopolyploid speciation in Spartina.

Abstract

The role of small RNAs on gene expression regulation and genome stability is arousing increased interest and is being explored in various plant systems. In spite of prominence of reticulate evolution and polyploidy that affects the evolutionary history of all plant lineages, very few studies analysed RNAi mechanisms with this respect. Here, we explored small RNAs diversity and expression in the context of recent allopolyploid speciation, using the Spartina system, which offers a unique opportunity to explore the immediate changes following hybridization and genome duplication. Small RNA-Seq analyses were conducted on hexaploid parental species (S. alterniflora and S. maritima), their F1 hybrid S. x townsendii, and the neoallododecaploid S. anglica. We identified 594 miRNAs, 2197 miRNA-target genes, and 3730 repeat-associated siRNAs (mostly targeting Class I/Copia-Ivana- Copia-SIRE and LINEs elements). For both mi- and ra-siRNAs, we detected differential expression patterns following genome merger and genome duplication. These misregulations include non-additive expression of miRNAs in the F1 hybrid and additional changes in the allopolyploid targeting developmental processes. Expression of repeat-associated siRNAs indicates a strengthen of transposable element repression during the allopolyploidization process. Altogether, these results confirm the central role small RNAs play in shaping regulatory changes in naturally formed recent allopolyploids.

  相似文献   
107.
Undaria pinnatifida, the brown macroalga, is a major commercial edible seaweed, and there is increasing interest in breeding new, improved cultivars for market expansion. In this study, we attempted to establish mutagenesis in U. pinnatifida using Ar and C ion beams as mutagens to meet future demands. To screen irradiated generations for mutants, U. pinnatifida zoospores irradiated with Ar and C ion beams were cultivated in plastic Petri dishes. Some gametophytes derived from the irradiated zoospores showed growth arrest or cell death at the initial developmental stage. Although the growth inhibition and lethal effects were observed at high doses of each ion irradiation, the Ar ion irradiation had high biological effects on cell division and growth. The gametophytes that showed a reduction in cell elongation were designated as an inhibited cell elongation mutant. A comparison of the mutant induction frequencies revealed that the C ion beam showed a higher frequency than the Ar ion beam. The highest frequency was 0.83% at 12.5 Gy of the C ion beam. We determined the total number of sporophytes and embryos per female gametophyte after sporophyte induction. High‐dose irradiation with the Ar ion beam decreased the embryo and sporophyte formation, suggesting that the Ar ion beam also has exhibited high biological effects on the fertilization or embryogenesis processes or both. The developed heavy ion mutagenesis and mutant screening methods would be useful for mutation breeding and constructing specific mutant libraries in brown algae, and not only in U. pinnatifida.  相似文献   
108.

Background

Diffuse astrocytomas are the most common type of primary brain cancer in adults. They present a wide variation in differentiation and aggressiveness, being classified into three grades: low-grade diffuse astrocytoma (grade II), anaplastic astrocytoma (grade III) and glioblastoma multiforme (grade IV), the most frequent and the major lethal type. Recent studies have highlighted the molecular heterogeneity of astrocytomas and demonstrated that large-scale analysis of gene expression could help in their classification and treatment. In this context, we previously demonstrated that HJURP, a novel protein involved in the repair of DNA double-strand breaks, is highly overexpressed in glioblastoma.

Methodology/Principal Findings

Here we show that HJURP is remarkably overexpressed in a cohort composed of 40 patients with different grade astrocytomas. We also observed that tumors presenting the higher expression levels of HJURP are associated with poor survival prognosis, indicating HJURP overexpression as an independent prognostic factor of death risk for astrocytoma patients. More importantly, we found that HJURP knockdown strongly affects the maintenance of glioblastoma cells in a selective manner. Glioblastoma cells showed remarkable cell cycle arrest and premature senescence that culminated in elevated levels of cell death, differently from non-tumoral cells that were minimally affected.

Conclusions

These data suggest that HJURP has an important role in the maintenance of extremely proliferative cells of high-grade gliomas and point to HJURP as a potential therapeutic target for the development of novel treatments for glioma patients.  相似文献   
109.
Rhizopus (Rh.) delemar were cultivated under the various conditions and the productivity of three lipases (A, B, and C) were examined. There seemed to be no remarkable change of A-lipase production so far as examined, however, the productions of B- and C-lipases were changed with correlation depending on the composition of the medium. B-lipase was increasingly produced as much as C-lipase production decreased by the presence of phospholipid in a culture medium. The property of C-lipase was so changed by the incubation with phospholipid as to agree with that of B-lipase. Besides the above, the property of B-lipase was changed by its purification to that of C-lipase.

From these results, it seems that B-lipase protein is the same as that of C-lipase and a phospholipid is related to the intercoversion from C-lipase to B-lipase.  相似文献   
110.
A series of sugar-modified porous silica monoliths with different sugar ligands (β-lactoside, β-N-acetyllactosaminide, β-d-galactoside, β-d-N-acetylgalactosaminide and β-d-glucoside) and linkers were prepared and evaluated using plant toxins and lectins including ricin and a Ricinus communis agglutinin (RCA120). Among these sugar monoliths, a lactose monolith carrying a triethylene glycol spacer adsorbed ricin and RCA120 with the highest efficiency. The monolith showed no binding with albumin, globulin, and lectins from Jack beans, Osage orange, Amur maackia and wheat germ. All these data support the utility of the lactose-modified monolith as a tool for adsorption and decontamination of plant toxins.  相似文献   
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