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51.
Plant Growth Regulation - Seed inoculation with microbial cells is one of the potential invigouration techniques for enhancing the emergence and growth of plants. Herein, we approached a new...  相似文献   
52.
This review will examine how dopamine, a monoamine neurotransmitter, and adenosine, a neuromodulator, regulate behavioral activation, primarily as reflected by locomotor activity, in rodents. Complex interactions among 2 major types of adenosine receptors (A1AR and A2AAR) and 2 dopamine receptors (D1R and D2R) occur due to physical interactions that alter their ligand-binding properties and subsequent effects on common postreceptor signaling molecules. The output from these interactions in striatum modulates neurotransmission and subsequently influences spontaneous locomotor activity. Caffeine is a nonselective adenosine receptor antagonist that blocks 2 major types of adenosine receptors, A1AR and A2AAR, in the brain. Pharmacologic manipulation of these receptors with drugs such as caffeine offers potential therapeutic benefit for treatment of Parkinson disease.  相似文献   
53.
Cancer prevention and treatment using phytochemicals have attracted increased interest. Recent studies have shown that Semecarpus anacardium Linn nut milk extract (SA), a promising antioxidant and anticancer drug, exerts its anticancer effect through reducing or quenching reactive oxygen species under different conditions. The present study examined whether Phyllanthus emblica Linn fruit, rich in vitamin C content synergistically in combination can enhance both the antioxidant and anticancer activity of S. anacardium nut milk extract in 7, 12-dimethyl benz[a]anthracene (DMBA)-induced experimental mammary carcinoma in rat model. Female Sprague Dawley rats of 180 ± 10g were categorized into six groups. Three groups were administered DMBA (25mg/rat, orally) dissolved in olive oil to induce mammary carcinoma. One of these groups received Kalpaamruthaa (KA) (300mg/kg b.wt, orally) and other group received SA (200mg/kg b.wt, orally) for 14 days after 90 days of DMBA induction. A vehicle treated control and drug control groups were also included. The mitochondrial fraction of untreated DMBA-induced mammary gland showed 2.61-fold increase in lipid peroxidation level and abnormal changes in the activities/levels of mitochondrial enzymic (superoxide dismutase, glutathione peroxidase and glutathione reductase) and non-enzymic (glutathione, vitamin C and vitamin E) antioxidants were observed. DMBA treated rats also showed decline in the activities of mitochondrial enzymes such as succinate dehydrogenase, malate dehydrogenase, α-ketoglutarate dehydrogenase and isocitrate dehydrogenase. In contrast, rats treated with Kalpaamruthaa showed normal lipid peroxide level and antioxidant defenses. The results of the present study highlight the improved antioxidant property of KA than sole treatment of S. anacardium nut milk extract.  相似文献   
54.
OBJECTIVES: Spontaneous preterm birth (PTB) has a significant ethnic disparity with people of African descent having an almost 2-fold higher incidence than those of European descent in the United States. This disparity may be caused by differences in the distribution of genetic risk factors. The objective of this study is to examine genetic differences between African-Americans and European Americans for single nucleotide polymorphisms (SNPs) in candidate genes for PTB. METHODS: We examined patterns of variation in 19 SNPs in 3 candidate genes for preterm birth: TNF-alpha, TNF-receptor 1 and TNF-receptor 2. Allele, genotype and haplotype frequencies were compared between African-Americans (AA) and European-Americans (EA) in cases and controls separately. Both maternal and fetal genotypes were studied, as it is unclear whether one or both of these are important in the etiology of PTB. RESULTS: The vast majority of the SNPs differed significantly between ethnic groups, although there are only a few suggestive results comparing cases and controls within an ethnic group. For TNF-alpha, four of six SNPs; for TNF-R1, 5/6; and for TNF-R2, 6/7 showed significant differences between ethnic groups in either allele and/or genotype frequency. CONCLUSIONS: Our data demonstrate highly significant genetic differences between ethnic groups in genes that may play a role in the risk of PTB.  相似文献   
55.
Two series of bicyclic oxime ethers viz, 2,4-diaryl-3-azabicyclo[3.3.1]nonan-9-one O-benzyloximes 1324 and 2,4,6,8-tetraaryl-3,7-diazabicyclo[3.3.1]nonan-9-one O-benzyloximes 3136 were synthesized and stereochemistry was established by their spectral (1D and 2D NMR) and crystal studies. Synthesized oxime ethers were screened for their in vitro antimicrobial activity against a set of pathogenic bacteria (Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhi, Escherichia coli and Klebsiella pneumoniae) and fungi (Candida albicans, Candida-51, Rhizopus sp., Aspergillus niger and Aspergillus flavus) by twofold serial dilution method, respectively, using Ciprofloxacin and Amphotericin B as standards. Most of the molecules expressed promising antimicrobial profile against the tested pathogens and even a few compounds 16, 21, 22, 33 and 34 were better than standard drugs.  相似文献   
56.
57.
To examine the role of the glycosphingolipid (GSL), globotriaosylceramide(Gb3, CD77, pk blood group antigen) in HIV-1 infection, we havepharmacologically modulated Gb3 metabolism in an X4 HIV-1 infectablemonocytic cell line (THP-1) that naturally expresses Gb3 andin a Gb3-expressing glioblastoma cell line (U87) transfectedto express both CD4 and CCR5 to permit R5 HIV-1 infection. THP-1and U87 cells were treated with either a competitive inhibitorof -galactosidase A, 1-deoxygalactonojirimycin (DGJ) to induceGb3 accumulation, or a glucosylceramide synthase inhibitor,phenyl-2-palmitylamino-3-pyrrolidino-1-propanol (P4) to depletecells of Gb3. HIV susceptibility was determined via measurementof p24gag antigen production by ELISA. In addition, total cellularGb3 content was determined using thin layer chromatography followedby Verotoxin1 overlay binding. The cell surface expression ofGb3 was verified by FACS analysis. We found that DGJ significantlydecreased THP-1 and U87 cell susceptibility to HIV-1IIIB andHIV-1BaL infection, respectively, at a concentration of approximately100 µM. In contrast, P4 (2 µM) substantiallyincreased cellular susceptibility to HIV-1 infection. Totalcellular GSL analysis verified increased Gb3 expression in cellstreated with DGJ and considerable reduction of Gb3 in P4-treatedcells as compared to controls. These results show a reciprocalrelationship between Gb3 expression and infection with eitherX4 HIV-1IIIB or R5 HIV-1Ba-L. These results support previousstudies that Gb3 provides resistance to HIV infection. VariableGb3 expression may provide a natural HIV resistance factor inthe general population, and pharmacological manipulation ofGb3 levels may provide an approach to induction of HIV resistance.  相似文献   
58.
In our previous investigations [1], urine of female mice contained specific compounds, namely isocroctylhydrazine, 4-methyl-2-heptanone, and azulene during proestrus, whereas during estrus it contained 1-H-cyclopop.e.azulene, caryophyllene, and copanene. Furthermore, 1-iodo-2 methyl undecane (1I2MU), present during both proestrus and estrus, was regarded as a putative estrus-specific chemo-signal [1]. The primary objective of the present study was to determine the estrogen-dependency of the above-mentioned compounds, including 1I2MU. Furthermore, the effect of these compounds on pre-mating behavior, e.g., sniffing, licking, and grooming, were recorded to determine their role as sex pheromones. Based on gas chromatography linked mass spectrometry (GC-MS) of urine samples, profiles in oophorectomized female mice had 14 major peaks. Furthermore, neither 1I2MU (nor other estrus-specific compounds) were detected in the urine of these mice, although they were detected in urine of proestrus and estrus mice. In addition, 1I2MU was not detected in urine of prepubertal mice. It was noteworthy that both 1I2MU and 4-methyl-2-heptanone reappeared in estrogen-treated females. Based on pre-mating behavioral analysis, 1I2MU was the compound most preferred by males. In conclusion, production of 1I2MU was estrogen-dependent in females, and it enhanced reproductive activities in males.  相似文献   
59.
Phenomics: the next challenge   总被引:4,自引:0,他引:4  
A key goal of biology is to understand phenotypic characteristics, such as health, disease and evolutionary fitness. Phenotypic variation is produced through a complex web of interactions between genotype and environment, and such a 'genotype-phenotype' map is inaccessible without the detailed phenotypic data that allow these interactions to be studied. Despite this need, our ability to characterize phenomes - the full set of phenotypes of an individual - lags behind our ability to characterize genomes. Phenomics should be recognized and pursued as an independent discipline to enable the development and adoption of high-throughput and high-dimensional phenotyping.  相似文献   
60.

Background

The use of biological annotation such as genes and pathways in the analysis of gene expression data has aided the identification of genes for follow-up studies and suggested functional information to uncharacterized genes. Several studies have applied similar methods to genome wide association studies and identified a number of disease related pathways. However, many questions remain on how to best approach this problem, such as whether there is a need to obtain a score to summarize association evidence at the gene level, and whether a pathway, dominated by just a few highly significant genes, is of interest.

Methods

We evaluated the performance of two pathway-based methods (Random Set, and Binomial approximation to the hypergeometric test) based on their applications to three data sets of Crohn's disease. We consider both the disease status as a phenotype as well as the residuals after conditioning on IL23R, a known Crohn's related gene, as a phenotype.

Results

Our results show that Random Set method has the most power to identify disease related pathways. We confirm previously reported disease related pathways and provide evidence for IL-2 Receptor Beta Chain in T cell Activation and IL-9 signaling as Crohn's disease associated pathways.

Conclusions

Our results highlight the need to apply powerful gene score methods prior to pathway enrichment tests, and that controlling for genes that attain genome wide significance enable further biological insight.  相似文献   
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