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1.
Rare earth metals play a conspicuous role in magnetic resonance imaging (MRI) for detecting cancerous cells. The alkali metal potassium is a neurotransmitter in the sodium–potassium pump in biomedical sciences. This unique property of rare earth metals and potassium drew our attention to carry forward this study. Therefore, in this work, previously synthesized potassium (K) complexes formed by the reflux of 4-N,N-dimethylaminobenzoic acid (DBA) and potassium hydroxide in methanol, and named [(μ2–4-N,N-dimethylaminobenzoate-κO)(μ2–4-N,N-dimethylaminobenzoic acid-κO)(4-N,N-dimethylaminobenzoic acid-κO) potassium(I) coordination polymer)] were treated hydrothermally with La2O3 nanomaterials to obtain a nanohybrid La2O3/K-complex. After that, the K-complex was analyzed using single-crystal X-ray diffraction and 1H and 13C NMR spectroscopy. In addition, the structural and morphological properties of the as-prepared nanostructured La2O3/K-complex were also characterized, which involved an investigation using X-ray diffraction (XRD)spectroscopy, Fourier transform infrared (FTIR) spectroscopy, atomic force spectroscopy (AFM), transmission electron microscopy (TEM), and energy dispersive X-ray (EDX) analysis. After this, the electrochemical redox behaviour of the synthesized nanohybrid material was studied using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Therefore, the results from these studies revealed that the as-prepared material was a La2O3/K-complex that has a promising future role in sensing various analytes, as it showed effective electrocatalytic behaviour.  相似文献   
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Journal of Plant Biochemistry and Biotechnology - Pigeonpea, an important legume crop is a good host plant for lac cultivation in North East India. In the present study, sixty-three polymorphic EST...  相似文献   
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Antonie van Leeuwenhoek - We report three yellow-pigmented, Gram-negative, aerobic, rod-shaped, motile bacterial isolates designated as PPL1T, PPL2, and PPL3 from healthy basmati rice seeds....  相似文献   
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The redox unbalance in erythrocytes has been found to contribute significantly in the development of anemia in visceral leishmaniasis (VL). The present study revealed enhanced production of reactive oxygen species (ROS) and gradual depletion of α-tocopherol and ascorbate in the erythrocytes of infected animals. The response of erythrocytes to chronic treatment with antioxidants was studied in hamsters during leishmanial infection. Treatment with a combination of α-tocopherol and ascorbate proved to be the most effective preventive for the proteolytic degradation of erythrocyte membrane. Erythrocytes from infected animals were thermally more sensitive compared to the control ones. Combination of both antioxidants was most successful in resisting heat induced structural defects in the cells. Cross-linking of membrane proteins subsequent to oxidative damage in the red cells was accompanied by the formation of high molecular weight protein band at the top of the resolving gel in the presence of the cross-linking agent dimethyladepimidate (DMA). Marked inhibition of cross-linking was observed with combination of both antioxidants. Treatment with α-tocopherol and ascorbate together could withstand osmotic lysis of erythrocytes in the infected animals very efficiently. Decreased hemoglobin (Hb) level was successfully replenished and was coupled with significant increase in the life span of red cells after treating the animals with both antioxidants. Results indicate better efficacy of the combination therapy with α-tocopherol and ascorbate in protecting the erythrocytes from structural and functional damages during leishmanial infection.  相似文献   
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The low engraftment and retention rate of mesenchymal stem cells (MSCs) at the target site indicates that the potential benefits of MSC-based therapies can be attributed to their paracrine signaling. In this study, the extracellular matrices (ECMs) deposited by bone marrow-derived human MSCs in the presence and absence of ascorbic acid was characterized. MSCs were seeded on top of decellularized ECM (dECM) and the concentrations of proangiogenic and antiangiogenic molecules released in culture (conditioned) media was compared. Effects of ECM derived from MSCs with different passage numbers on MSC secretome was also investigated. Our study revealed that the expression of proangiogenesis-related factors were upregulated when MSCs were harvested on dECMs, irrespective of media supplementation, as compared with those cultured on tissue culture plates. In addition, dECM generated in the presence of ascorbic acid promoted the expression of proangiogenic molecules as compared with dECM-derived in absence of media supplementation. Further, it was observed that the effectiveness of dECM to stimulate proangiogenic signaling of MSCs was reduced as cell passage number was increased from P3 to P5. The proliferation as well as capillary morphogenesis of human umbilical vein endothelial cells (HUVECs) in the presence of conditioned media were enhanced compared with the normal HUVECs culture media. These data indicate that the secretory signatures of MSCs and consequently, the therapeutic efficacy of MSCs can be regulated by presentation of dECM composition and variation of its composition.  相似文献   
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INTRODUCTION:

The relationship between chromosomal non-disjunction leading to aneuploidy and folate metabolism has drawn attention in the recent years. In this study, we examined the polymorphism in the gene encoding the folate metabolizing enzyme methylenetetrahydrofolate reductase (MTHFR), namely, 677 C-T in women having Down syndrome (DS) children.

MATERIALS AND METHODS:

The prevalence of these variant genotypes (MTHFR 677 C-T polymorphism) in women having DS children (case mothers) (n = 110) was compared with controls (n = 111) from Punjab. Genotyping was done using the polymerase chain reaction method followed by restriction fragment length polymorphism.

RESULTS:

In the present study, 1.8% of case mothers had TT genotype while none of the control mothers showed this genotype. T allele frequency among cases was 0.13 and 0.11 in controls. The Chi-square value showed a non-significant difference between cases and controls.

CONCLUSION:

No association has been observed between 677 C-T polymorphism and risk of non-disjunction in case mothers. Detection of polymorphisms in more genes of folate pathway is required to find out the exact cause of non-disjunction.  相似文献   
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Biological Trace Element Research - This research article aims to establish the intake ratio of probiotic Lactobacillus plantarum 299v with iron supplement pearl millet by central composite design...  相似文献   
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BACKGROUND AND AIMS: High lignin content of lignocellulose jute fibre does not favour its utilization in making finer fabrics and other value-added products. To aid the development of low-lignin jute fibre, this study aimed to identify a phloem fibre mutant with reduced lignin. METHODS: An x-ray-induced mutant line (CMU) of jute (Corchorus capsularis) was morphologically evaluated and the accession (CMU 013) with the most undulated phenotype was compared with its normal parent (JRC 212) for its growth, secondary fibre development and lignification of the fibre cell wall. KEY RESULTS: The normal and mutant plants showed similar leaf photosynthetic rates. The mutant grew more slowly, had shorter internodes and yielded much less fibre after retting. The fibre of the mutant contained 50 % less lignin but comparatively more cellulose than that of the normal type. Differentiation of primary and secondary vascular tissues throughout the CMU 013 stem was regular but it did not have secondary phloem fibre bundles as in JRC 212. Instead, a few thin-walled, less lignified fibre cells formed uni- or biseriate radial rows within the phloem wedges of the middle stem. The lower and earliest developed part of the mutant stem had no lignified fibre cells. This developmental deficiency in lignification of fibre cells was correlated to a similar deficiency in phenylalanine ammonia lyase activity, but not peroxidase activity, in the bark tissue along the stem axis. In spite of severe reduction in lignin synthesis in the phloem cells this mutant functioned normally and bred true. CONCLUSIONS: In view of the observations made, the mutant is designated as deficient lignified phloem fibre (dlpf). This mutant may be utilized to engineer low-lignin jute fibre strains and may also serve as a model to study the positional information that coordinates secondary wall thickening of fibre cells.  相似文献   
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