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111.
This paper describes the use of a quantitative competitive polymerase chain reaction (QC-PCR) assay; using PCR primers to the rRNA locus of rumen fungi and a standard-control DNA including design and validation. In order to test the efficiency of this method for quantifying anaerobic rumen fungi, it has been attempted to evaluate this method in in vitro conditions by comparing with an assay based on measuring cell wall chitin. The changes in fungal growth have been studied when they are grown in in vitro on either untreated (US) or sodium hydroxide treated wheat straw (TS). Results showed that rumen fungi growth was significantly higher in treated samples compared with untreated during the 12 d incubation (P < 0.05) and plotting the chitin assay's results against the competitive PCR's showed high positive correlation (R2 ≥ 0.87). The low mean values of the coefficients of variance in repeatability in the QC-PCR method against the chitin assay demonstrated more reliability of this new approach. And finally, the efficiency of this method was investigated in in vivo conditions. Samples of rumen fluid were collected from four fistulated Holstein steers which were fed four different diets (basal diet, high starch, high sucrose and starch plus sucrose) in rotation. The results of QC-PCR showed that addition of these non-structural carbohydrates to the basal diets caused a significant decrease in rumen anaerobic fungi biomass. The QC-PCR method appears to be a reliable and can be used for rumen samples.  相似文献   
112.
Defect in cell cycle control is a hallmark character of cancer. We have investigated the association of Ki67 labeling index, cyclin E and CDC25A expressions with clinical follow-up data in breast carcinomas. Flow cytometry was used to detect gene amplification of cyclins in 44 tumor tissue with invasive breast carcinomas. Multivariate Cox proportional hazard ratio test was used to show the correlations. Cyclin E or CDC25A were upregulated in 34% of the tumors. Among the whole total material, expression of cyclin E and of CDC25A were found upregulated in 31.9% and 39.4% of cells, respectively. Both CDC25A and cyclin E protein expression levels were correlated with Ki67 expression level (p < 0.001). In addition, the expression of CDC25A was associated significantly with poor survival (P = 0.028), whereas no correlation was found with cyclin E. These findings suggest a possible prognostic value for CDC25A as a cell cycle marker and may imply in characteristic of high risk breast cancer patients.  相似文献   
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114.
Seven ab initio web-based gene prediction programs (i.e., AUGUSTUS, BGF, Fgenesh, Fgenesh+, GeneID, Genemark.hmm, and HMMgene) were assessed to compare their prediction accuracy using protein-coding sequences of bread wheat. At both nucleotide and exon levels, Fgenesh+ was deduced as the superior program and BGF followed by Fgenesh were resided in the next positions, respectively. Conversely, at gene level, Fgenesh with the value of predicting more than 75% of all the genes precisely, concluded as the best ones. It was also found out that programs such as Fgenesh+, BGF, and Fgenesh, because of harboring the highest percentage of correct predictive exons appear to be much more applicable in achieving more trustworthy results, while using both GeneID and HMMgene the percentage of false negatives would be expected to enhance. Regarding initial exon, overall, the frequency of accurate recognition of 3′ boundary was significantly higher than that of 5′ and the reverse was true if terminal exon is taken into account. Lastly, HMMgene and Genemark.hmm, overall, presented independent tendency against GC content, while the others appear to be slightly more sensitive if GC-poor sequences are employed. Our results, overall, exhibited that to make adequate opportunity in acquiring remarkable results, gene finders still need additional improvements.  相似文献   
115.
International Journal of Peptide Research and Therapeutics - Some chemokines and chemokine receptors play important roles in various types of autoimmune diseases, infectious diseases and cancer...  相似文献   
116.
Endometriosis is a frequent and chronic illness in young women which could be defined by the existence of endometrial stroma and glands outside of the normal site of the lining of the uterus. It has painful symptoms. The advanced stage of endometriosis may lead to gynecological malignancies, such as ovarian cancer, and other complications, including infertility. However, its exact physiopathology is not well known. Recent studies have shown the possible roles of inflammation along with oxidative stress. Additionally, angiogenesis and apoptosis dysregulation contribute to endometriosis pathophysiology. Therapeutic strategies and continuing attempts, to conquer endometriosis should be done regarding molecular signaling pathways. Thus, the present review summarizes current studies and focuses on molecular mechanisms.  相似文献   
117.
Alzheimer's disease (AD) is a major health problem worldwide, with no effective treatment approach. Curcumin is the main ingredient of turmeric traditionally used in Asian medicine. Several experimental studies have indicated the protective effect of curcumin and its novel formulations in AD. Curcumin has antioxidant, anti-inflammatory and neurotrophic activities, proposing a strong potential to prevent neurodegenerative diseases. However, there are no sufficient clinical trials to confirm curcumin use in AD patients. Low bioavailability following oral administration of curcumin limits its usage in human. The present study was designed to gather the effects of curcumin and its modified formulations in human and experimental models of AD.  相似文献   
118.
Since the beginning of the 21st century, studies have focused on developing drugs from naturally occurring compounds. Berberine (Brb) as a plant-derived compound is of interest. It is an isoquinone alkaloid which is derived from Berberis aristata, Berberis aquifolium and Berberis vulgaris. This plant-derived compound has a variety of pharmacological effects such as antioxidant, anti-inflammatory, antidiabetic, antidiarrheal, antitumor, antimicrobial, and anti-inflammatory. Various studies have demonstrated the therapeutic and biological activities of Brb, but there is a lack of a precise review to manifest the signaling pathway of action of Brb. The nuclear factor erythroid 2-related factor 2 (Nrf2) is a highly conserved pathway which mainly involves in preservation of redox balance. At the present review, we describe the therapeutic and biological activities of Brb as well as the relevant mechanisms specially focused on the Nrf2 signaling pathway.  相似文献   
119.
Defoliation by the vegetable leafminer, Liriomyza sativae Blanchard (Diptera: Agromyzidae), was simulated by removing known amounts of leaf area with a hole punch in a glasshouse experiment that evaluated 21 combinations of defoliation intensity, timing and duration on cucumber yields. Defoliation was quantified in cm2-days (leaf area removed x no. days), and linear regression was used to correlate yield losses to simulated damage. The probability of erroneous decisions associated with different intensities of sequential sampling was explored. Spatial heterogeneity in leafminer infestation and the cumulative impact of defoliation over time were both considered, and the economic costs associated with wrong decisions were also assessed. Significant yield loss was observed beyond 10,000 cm2-days of defoliation, whereas lower defoliation levels were tolerated by plants. The economic injury level (EIL) rose at an increasing rate as the onset of defoliation moved later in the season. An algorithm was used to estimate monthly EILs that farmers can use to guide leafminer management decisions in cucumber and minimize their economic risk.  相似文献   
120.
Cell transplantation shows potential for the treatment of cardiac diseases. Embryonic stem cells, cord blood and mesenchymal stem cells have been suggested as sources for transplantation therapy. Because of some technical limitations with the use of stem cells, transdifferentiation of fully differentiated cells is a potentially useful alternative. We investigated whether human peripheral blood cells could transdifferentiate into cardiomyocyte. Transdifferentiation was induced in a human B lymphocyte cell line (Raji). Cardiomyocyte extract was prepared from adult mouse cardiomyocytes. The cells were treated with 5-aza-2-deoxycytidine and trichostatin A, permeabilized with streptolysin O, and exposed to the mouse cardiomyocyte extract. They were cultured for 10 days, 3 weeks and 4 weeks. Cardiomyocyte markers were detected with immunohistochemistry and flow cytometry. Immunocytochemistry revealed that some cells expressed myosin heavy chain, α-actinin and cardiac troponin T after 3 and 4 weeks. Flow cytometry confirmed these data. In cells exposed to trichostatin A and 5-aza-2-deoxycytidine and permeabilized in the presence of the cardiomyocyte extract, troponin T expression was seen in 3.53% of the cells and 3.11% of them expressed α-actinin. After exposure to the cardiomyocyte extract, some permeabilized cells adhered to the plate loosely; however, the morphology did not change significantly, and they continued to show a rounded shape after 4 weeks. Our treated lymphocytes expressed cardiomyocyte markers. Our results suggest that lymphocytes may be useful in future research as a source of cells for reprogramming procedures.  相似文献   
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