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61.
A group of 4-allyloxyaniline amides 5ao were designed, synthesized and evaluated as potential inhibitors of soybean 15-lipoxygenase (SLO) on the basis of eugenol and esteragol structures. Compound 5e showed the best IC50 in SLO inhibition (IC50 = 0.67 ± 0.06 μM). All compounds were docked in SLO active site retrieved from RCSB Protein Data Bank (PDB entry: 1IK3) and showed that allyloxy group of compounds is oriented towards the Fe3+-OH moiety in the active site of enzyme and fixed by hydrogen bonding with two conserved His513 and Gln716. It is resulted that molecular volume of the amide moiety would be a major factor in inhibitory potency variation of the synthetic amides, where the hydrogen bonding of the amide group could also involve in the activity of the inhibitors.  相似文献   
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The pathway to reach a certain target in many processes such as bioleaching, due to the complex and poorly understood hydrodynamics, reaction kinetics, and chemistry knowledge involved is not apparent. An investigation of the interactions between the parameters in bioleaching process can be applied to optimize the rate of metal extraction from sulphide minerals. Such investigations can be carried out with the aid of numerical simulations. In this study, a computational fluid dynamics (CFD) model was developed to better understand the mass transfer phenomenon and complex flow field around a single particle. The commercial software FLUENT 6.2 has been employed to solve the governing equations. Volume of fluid (VOF) method was used to predict the fluid volume fraction in a 3D geometry. The computational model has successfully captured the results observed in the experiments. Simulation results indicate that concentrations of species in a thin layer of liquid on the particle surface are much higher than their concentrations in the liquid bulk and significant gradients in the ion concentrations between the surface of the particle and the liquid bulk were observed.  相似文献   
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Expression of anti human IL-4 and IL-6 scFvs in transgenic tobacco plants   总被引:3,自引:0,他引:3  
The two murine single-chain Fv (scFv) genes against human interleukin IL-4 and IL-6 cytokines were cloned in a plant expression vector (pGEJAE1) and mobilized to Agrobacterium tumefaciens. Tobacco leaf discs were co-cultured with Agrobacterium and transferred to selective media for regeneration. The tobacco in vitro plants produced scFvs against human IL-4 and IL-6. Only 8% of transformed plants expressing anti-IL-4 scFv were obtained versus 76% of transformed plants expressing anti-IL-6 scFv. In addition, some plants producing anti-IL-4 and anti-IL-6 scFvs aged more rapidly in in vitro conditions and in greenhouse pots than did control plants. Western blot analysis showed that the transformed Nicotiana tabacum plants contained proteins with an apparent molecular mass on electrophoresis of ca. 32 kDa, corresponding to the predicted size of the scFvs. As entire plant root seemed to accumulate more scFv than did leaves, we decided to continue working with isolated roots. Anti-IL-6 scFvs were detected in cultivated roots and their culture media. Functional anti-IL-6 scFv accounted for 0.16–0.18% of total soluble proteins. The affinity of the anti-IL-6 scFv produced in plants and measured by Biacore was similar to that of scFv produced in Escherichia coli. The high levels of antibody accumulation in isolated roots and secretion into the medium demonstrate the potential for producing recombinant protein in bioreactor systems.these authors contributed equally to this workthese authors contributed equally to this work  相似文献   
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This study evaluated several secondary metabolites, essential oils (EOs) compositions, and antioxidant activity in four medicinal plants that originated in Isfahan rangelands. The species were Astragalus verus, Astragalus adscendens, Daphne mucronata, and Phlomis olivieri. Thirty-two genotypes of these species were evaluated for different biochemical traits. Based on the evaluation of EOs compounds, GC/MS analysis revealed the total number of identified compounds. These compounds were 25, 22, 12, and 22 for A. adscendens, A. verus, D. mucronata, and P. olivieri, respectively. The dominant compounds were phthalate (59.88 %) in A. adscendens, phytol (38.02 %) in A. verus, hexanoic acid (32.05 %) in D. mucronata and β-cubebene (30.94 %) in P. olivieri. Phytochemical analysis showed that D. mucronata, A. adscendens, and P. olivieri had the highest total phenolics content (TPC) (18.24 mg gallic acid equivalent/g dry weight), total flavonoids content (5.57 mg QE/g DW), and total anthocyanins content (0.23 mg/g DW), respectively. The highest total chlorophyll (0.27 mg/g DW), total carotenoids (0.03 mg/g DW), and antioxidant activity (71.36 %) were observed in A. adscendens, A. adscendens and A. verus, respectively. Among all genotypes, the highest TPC (20.1 mg GAE/g DW) was observed in genotype 5 of D. mucronata. This study provided new information on the chemical compounds within the distribution range of these ecologically dominant rangeland species in Isfahan province, Iran. The data revealed that superior genotypes from these species are rich in natural antioxidants and bioactive compounds. Thus, they can be used in ethno pharmacological fields, food, and industrial applications.  相似文献   
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Aim. Pulmonary complications are known to occur in over half the patients exposed to sulphur mustard. Many studies have focused on the clinical complications, often ignoring the pathogenesis of sulphur mustard. Also, the reasons for the variable severity of lung injuries caused by sulphur mustard are unclear. Hence, the current study was performed to evaluate the correlation between superoxide dismutase (SOD) and catalase (CAT) activity and pulmonary function in patients exposed to sulphur mustard. Methods. Our study was a comparative cross-sectional survey. Two hundred and fifty incident survivors were selected from the Sardasht population who were exposed to sulphur mustard in 1987. A control group from non-exposed civilians was also selected. We used a pulmonary function test, and SOD and CAT activity was measured in these groups. Results. The mean SOD activity in the healthy control group (70.5±10.8 U ml?1) was higher than in the moderate-to-severe group (67.0±6.1 U ml?1) (p <0.001, one-tail ANOVA, least significant difference (LSD) post hoc). The mean activity in the mild group (72.5±6.9 U ml?1) was no higher than in the healthy control group (70.5±10.8 U ml?1) (p=0.095 one-tail ANOVA, LSD post hoc). The mean CAT activity in the healthy control group (4.9±1.5 U ml?1) was lower than in the moderate-to-severe group (8.0±1.8 U ml?1) (p <0.001, one-tail ANOVA, LSD post hoc) and in the mild group (7.5±1.5 U ml?1) (p=0.012 one-tail ANOVA, LSD post hoc). Conclusion. According to our findings, it is reasonable to hypothesize that re-establishment of the activation–inactivation or oxidant–antioxidant balance in favour of the activation and antioxidant balances would be useful as a therapeutic strategy to suppress pathological mechanisms underlying lung injuries.  相似文献   
68.

Background

Cigarette smoking is the major risk factor for COPD, leading to chronic airway inflammation. We hypothesized that cigarette smoke induces structural and functional changes of airway epithelial mitochondria, with important implications for lung inflammation and COPD pathogenesis.

Methods

We studied changes in mitochondrial morphology and in expression of markers for mitochondrial capacity, damage/biogenesis and fission/fusion in the human bronchial epithelial cell line BEAS-2B upon 6-months from ex-smoking COPD GOLD stage IV patients to age-matched smoking and never-smoking controls.

Results

We observed that long-term CSE exposure induces robust changes in mitochondrial structure, including fragmentation, branching and quantity of cristae. The majority of these changes were persistent upon CSE depletion. Furthermore, long-term CSE exposure significantly increased the expression of specific fission/fusion markers (Fis1, Mfn1, Mfn2, Drp1 and Opa1), oxidative phosphorylation (OXPHOS) proteins (Complex II, III and V), and oxidative stress (Mn-SOD) markers. These changes were accompanied by increased levels of the pro-inflammatory mediators IL-6, IL-8, and IL-1β. Importantly, COPD primary bronchial epithelial cells (PBECs) displayed similar changes in mitochondrial morphology as observed in long-term CSE-exposure BEAS-2B cells. Moreover, expression of specific OXPHOS proteins was higher in PBECs from COPD patients than control smokers, as was the expression of mitochondrial stress marker PINK1.

Conclusion

The observed mitochondrial changes in COPD epithelium are potentially the consequence of long-term exposure to cigarette smoke, leading to impaired mitochondrial function and may play a role in the pathogenesis of COPD.  相似文献   
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Biotechnology Letters - Tumor suppressor miRNAs, miR-15a and miR-16–1, with high-specificity and oncogenic targeting of Bcl-2, can target tumor tissues. Disadvantages of the clinical...  相似文献   
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