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101.
Mitogen-activated protein kinases (MAPKs) are crucial Ser/Thr protein kinases that play important roles in innate immunity by converting extracellular stimuli into a wide range of cellular responses, including the production of cytokines. In this study, two MAPK genes, jnk1 and erk1, were cloned and characterized in rohu (Labeo rohita), a commercially important freshwater fish species in the Indian subcontinent. In healthy rohu, both jnk1 and erk1 gene expressions were highest in the spleen as compared to gill, liver, blood and kidney tissues. In vitro stimulation of the L. rohita gill (LRG) cell line with γ-D-glutamyl-meso-diaminopimelic acid, muramyl dipeptide and polyinosinic: polycytidylic acid (poly I:C) resulted in significantly enhanced expressions of jnk1 and erk1 genes. In the in vivo experiments, jnk1 and erk1 gene expressions were also enhanced in lipopolysaccharides and poly I:C-treatment. Infection of rohu fingerlings with Aeromonas hydrophila and Bacillus subtilis revealed significantly enhanced expressions of the jnk1 and erk1 genes in all of the tested organs/tissues. Together these results imply the important role of jnk1 and erk1 genes in fish during pathogenic invasion and diseases.  相似文献   
102.
Clinical trials using human Mesenchymal Stem Cells (MSCs) have shown promising results in the treatment of various diseases. Different tissue sources, such as bone marrow, adipose tissue, dental pulp and umbilical cord, are being routinely used in regenerative medicine. MSCs are known to reduce increased oxidative stress levels in pathophysiological conditions. Differences in the ability of MSCs from different donors and tissues to ameliorate oxidative damage have not been reported yet. In this study, for the first time, we investigated the differences in the reactive oxygen species (ROS) reduction abilities of tissue-specific MSCs to mitigate cellular damage in oxidative stress. Hepatic Stellate cells (LX-2) and cardiomyocytes were treated with Antimycin A (AMA) to induce oxidative stress and tissue specific MSCs were co-cultured to study the reduction in ROS levels. We found that both donor’s age and source of tissue affected the ability of MSCs to reduce increased ROS levels in damaged cells. In addition, the abilities of same MSCs differed in LX-2 and cardiomyocytes in terms of magnitude of reduction of ROS, suggesting that the type of recipient cells should be kept in consideration when using MSCs in regenerative medicine for treatment purposes.  相似文献   
103.
The present study focused on identification and genotypic characterization of Lactic acid bacteria (LAB) in the intestine of freshwater fish. 76 strains of LAB were isolated and identified by 16S rRNA gene sequences and hsp60 gene sequences as different strains of Lactobacillus plantarum, Lactobacillus pentosus, Lactobacillus fermentum, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus brevis, Lactobacillus reuteri, Lactobacillus salivarius, Pediococcus pentosaceus, Pediococcus acidilactici, Weissella paramesenteroides, Weissella cibaria, Enterococcus faecium, and Enterococcus durans. The hsp60 gene showed a higher level of sequence variation among the isolates examined, with lower interspecies sequence similarity providing more resolutions at the species level than the 16S rRNA gene. Phylogenetic tree derived from hsp60 gene sequences with higher bootstrap values at the nodal branches was more consistent as compared to phylogenetic tree constructed from 16S rRNA gene sequences. Closely related species L. plantarum and L. pentosus as well as species L. delbrueckii subsp. bulgaricus and L. fermentum were segregated in different cluster in hsp60 phylogenetic tree whereas such a distribution was not apparent in 16S rRNA phylogenetic tree. In silico restriction analysis revealed a high level of polymorphism within hsp60 gene sequences. Restriction pattern with enzymes AgsI and MseI in hsp60 gene sequences allowed differentiation of all the species including closely related species L. plantarum and L. pentosus, E. faecium and E. durans. In general, hsp60 gene with higher evolutionary divergence proved to be a better phylogenetic marker for the group LAB.  相似文献   
104.

Background and aims

Elemental uptake in serpentine floras in eastern North America is largely unknown. The objective of this study was to determine major and trace element concentrations in soil and leaves of three native pseudo-metallophyte C4 grasses in situ at five sites with three very different soil types, including three serpentine sites, in eastern USA.

Methods

Pseudo-total and extractible concentrations of 15 elements were measured and correlated from the soils and leaves of three species at the five sites.

Results

Element concentrations in soils of pseudo-metallophytes varied up to five orders of magnitude. Soils from metalliferous sites exhibited higher concentrations of their characteristic elements than non-metalliferous. In metallicolous populations, elemental concentrations depended on the element. Concentrations of major elements (Ca, Mg, K) in leaves were lower than typical toxicity thresholds, whereas concentrations of Zn were higher.

Conclusions

In grasses, species can maintain relatively low metal concentrations in their leaves even when soil concentrations are richer. However, in highly Zn-contaminated soil, we found evidence of a threshold concentration above which Zn uptake increases drastically. Finally, absence of main characteristics of serpentine soil at one site indicated the importance of soil survey and restoration to maintain serpentinophytes communities and avoid soil encroachment.
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105.
OBJECTIVE: This study was undertaken to determine the prevalence and molecular basis of alpha-thalassemia in the Indian population and its implications in genetic counseling and prenatal diagnosis. METHODS: 1253 random samples were screened for hemoglobinopathies. Red cell indices were measured on the Sysmex K 1000 cell counter; HbA2 and HbF levels were quantitated using high performance liquid chromotography (HPLC). Cellulose acetate electrophoresis and isoelectric focusing (IEF) was done to detect the presence of Hb Bart's in cord blood samples. alpha-Globin gene mapping was done using Southern blot hybridization of BamHI and BglII digests. RESULTS: Of the 1253 subjects, 132 had a single alpha-gene deletion (10.5%) while 29 had two alpha-gene deletions (2.31%). Fifteen cases showed the presence of alpha-gene triplication (1.1%). A single case showed the presence of one alpha-gene deletion as well as alpha-gene triplication (-alpha/alphaalphaalpha). Overall, the prevalence of alpha-thalassemia was 12.9%. Region-wise and caste-wise analysis showed the highest prevalence of alpha-thalassemia among the Punjabi population originating from the northern region of India. CONCLUSION: alpha-Thalassemia is by far the commonest hemoglobinopathy in India, but it is not a cause of serious genetic risk is the milder form (-alpha/alphaalpha) of alpha-thalassemia, which is predominant. Knowing the alpha-genotype is useful for genetic counseling for prenatal diagnosis in couples where one of the parents may have reduced indices coupled with a raised RBC count and normal HbA2 levels.  相似文献   
106.
Ground state absorption and steady-state and time-resolved fluorescence measurements have been carried out to understand the host-guest interactions of p-diethylaminobenzonitrile (DEABN) and p-dimethylaminobenzonitrile (DMABN) dyes with alpha-cyclodextrin (alpha-CD) and beta-cyclodextrin (beta-CD) hosts. DEABN and DMABN dyes show both locally excited (LE) state and intramolecular charge transfer (ICT) state emissions in solution. The LE and ICT emissions of the dyes are seen to get modulated in the presence of alpha-CD and beta-CD hosts. The results indicate that the dyes form 1 : 1 inclusion complexes with both the hosts. Comparing the binding constants and the fluorescence characteristics of different dye x CD systems it is inferred that DEABN adopts a completely different orientation on complexation with alpha-CD than in the other cases of dye.CD systems. It is indicated that while in all other cases of dye x CD systems the N,N-dialkyl group of the dyes enters the host cavity leaving the C[triple bond, length as m-dash]N group projected out into the water phase, the DEABN dye enters the alpha-CD cavity (smallest CD) with its C[triple bond, length as m-dash]N group entering the host cavity. The differences in the orientation of the dye in the host cavities is understood to be determined by the requirement of maximum van der Waals contact of the encapsulated dye with the host cavity for maximum stability of the complex and the relative sizes of the substituents of the dye compared to the host cavities. From the observation that the binding constants for the present dye x CD systems are not that significantly high, it is inferred that the hydrophobic interaction mainly govern the inclusion complex formation in the present systems.  相似文献   
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109.
Metastasis is the leading cause of death in cancer patients. To understand the mechanism of metastasis, an experimental metastasis assay was established using immunodeficient mice. This article delineates the procedures involved in this assay, including sample preparation, intravenous injection, and culturing cells from lung metastases. Briefly, a pre-determined number of human cancer cells were prepared in vitro and directly injected into the circulation of immunodeficient mice through their tail veins. A small number of cells survive the turbulence in the circulation and grow as metastases in internal organs, such as lung. The injected mice are dissected after a certain period. The tissue distribution of metastases is determined under a dissecting microscope. The number of metastases in a specific tissue is counted and it directly correlates with the metastatic ability of the injected cancer cells. The arisen metastases are isolated and cultured in vitro as cell lines, which often show enhanced metastatic abilities than the parental line when injected again into immunodeficient mice. These highly metastatic derivatives become useful tools for identifying genes or molecular pathways that regulate metastatic progression.Download video file.(50M, mov)  相似文献   
110.
The Asian rice gall midge, Orseolia oryzae Wood-Mason (Cecidomyiidae: Diptera) is a serious pest of wet season rice in South and Southeast Asia. Due to internal feeding habit and presence of biotypes of the pest, the most feasible way to control is breeding varieties resistant against multiple biotypes through marker-assisted breeding (MAB). But very few versatile co-dominant markers linked to the gall midge resistance genes are available. We used a set of F9 recombinant inbred lines (RILs) of the cross TN1/PTB10 and identified microsatellite markers for the gall midge resistance gene in cv. PTB10 on short arm of rice chromosome 8. Markers RM22550 and RM547 flank the gene at a distance of 0.9 and 1.9 cM, respectively. Amplification of the markers in gall midge resistant and susceptible cultivars showed that these markers can be successfully used in MAB for development of gall midge resistant varieties.  相似文献   
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