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81.
Inoculated and non-inoculated seedlings of maize were grown in fertile clayloam soils of Egypt and Belgium under subtropical conditions provided in a greenhouse. Acetylene-reducing activity and microbial counts were determined during a period ranging from 6 to 12 weeks after sowing. Irrespective of soil origin, N(2)-fixing spirilla and Azotobacter were common under maize cultivation. Inoculation resulted in a transitional increase in their numbers at early stages of growth. Nitrogenase activity was not detected in the rhizosphere of young plants. The maximum activities measured (81 to 1,436 nmol of C(2)H(4) g h) occurred close to the 50 to 70% silking stage. Inoculation with N(2)-fixing spirilla, particularly in Nile Delta soil, doubled the amount of N(2) fixed in a late period of growth (12 weeks), whereas inoculation with Azotobacter had no noticeable effect.  相似文献   
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6-Hydroxydopamine (6-OHDA), a metabolite of dopamine is known to induce dopaminergic cell toxicity which makes that a suitable agent inducing an experimental model of Parkinson’s disease (PD). Agmatine has been shown to protect against some cellular and animal PD models. This study was aimed to assess whether agmatine prevents 6-OHDA-induced SH-SY5Y cell death and if yes, then how it affects Akt/glycogen synthesis kinase-3β (GSK-3β) and extracellular signal-regulated kinases (ERK) signals. The cells were treated with different drugs, and their viability was examined via MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay and morphological observation. Western blot studies were done to assess cleaved caspase-3, Akt/GSK-3β, and ERK proteins. 6-OHDA-induced cell death and caspase-3 cleavage, while agmatine prevented those changes. 6-OHDA also decreased the amount of phosphorylated Akt (pAkt)/Akt while increased GSK-3β activity which was prevented by agmatine. Additionally, this toxin increased pERK/ERK ratio which was averted again by agmatine. The PI3/Akt inhibitor, LY294002, impeded the changes induced by agmatine, while ERK inhibitor (PD98059) did not disturb the effects of agmatine, and by itself, it preserved the cells against 6-OHDA toxicity. This study revealed that agmatine is protective in 6-OHDA model of PD and affects Akt/GSK-3β and ERK pathways.  相似文献   
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Molecular Biology Reports - Important regulatory roles of long non-coding RNAs (lncRNAs) have been recently found, and reported as useful biomarkers in cancer. To identify a potential expression of...  相似文献   
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Objective: There is an increased prevalence of macrovascular disease in type 2 diabetes. The pathogenesis has been related to metabolic risk factors, insulin resistance, and obesity. One of the strongest predictors is the presence of subclinical atherosclerosis. This study was designed to examine the relationship between obesity and regional patterns of adiposity, insulin resistance, and five independent measures of subclinical atherosclerosis. Research Methods and Procedures: Fifty‐two overweight and obese men and women with type 2 diabetes of relatively short known duration were examined. Measures of subclinical vascular disease were assessment of arterial stiffness by pulse wave velocity, ultrasound measurement of the carotid artery intimal‐medial thickness and plaque index, and measurement of the extent of coronary and aortic calcification using electron beam computed tomography. Insulin resistance was measured using the hyperinsulinemic euglycemic clamp. Body composition was measured using DXA and computed tomography. Results: Adiposity was a strong determinant of pulse wave velocity. Carotid intimal‐medial thickness was correlated with age, low‐density lipoprotein‐cholesterol, and hyperglycemia, but not with adiposity. Hyperglycemia and plasma activator inhibitor‐1 were significant correlates of the carotid artery plaque index. Coronary calcium scores were significantly correlated with age and interleukin‐6 and significantly and negatively correlated to insulin sensitivity index. Discussion: These findings suggest that obesity may play an important role in the early phase of subclinical macrovascular disease related to vessel stiffness, whereas hyperglycemia and insulin resistance in conjunction with other risk factors have important roles in progression from vessel stiffness to atheroma formation in type 2 diabetes.  相似文献   
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Background:The effect of total suspended particulate matter (TSP) was investigated on the expression of inflammatory and apoptotic factors in diabetic rats, and the effect of crocin and insulin was examined on these factors.Methods:Fifty-four adult male wistar rats were divided into nine experimental groups: control group, crocin group (received crocin, 50 mg/kg), diabetic group (received a single dose of alloxan at 120 mg/kg, IP), TSP group (5 mg/kg TSP instilled intratracheally), diabetic-crocin group (received crocin at 50 mg/kg after the induction of diabetes by alloxan (120 mg/kg)), diabetic-insulin group (received regular insulin (5 U/kg), crocin-TSP group (received crocin at 50 mg/kg, IP, and then 5 mg/kg TSP was instilled intratracheally), diabetic-TSP-insulin group (after receiving alloxan (120 mg/kg) and instilling TSP (5 mg/kg, intratracheally), a single dose (5 U/kg) of regular insulin), and diabetic-TSP-crocin group (after receiving alloxan (120 mg/kg) and instilling TSP (5 mg/kg, intratracheally), a single dose of crocin (50 mg/kg, IP)). Quantitative real-time PCR was performed to measure the expression of the mRNAs of apoptotic (Bax and Bcl2) and inflammatory mediators (TNFα, COX2, iNOS/eNOS) in Wistar rats.Results:In diabetic and TSP groups the inflammatory factors and BAX/Bcl2 ratio significantly increased compared to the control group. In diabetic-TSP-insulin and diabetic-TSP-crocin, a significant decrease was observed in the rate of inflammatory factors and BAX/Bcl2 ratio.Conclusion:The results suggested that diabetes and exposure to TSP increase the rate of apoptosis and inflammation, and also demonstrated the anti-apoptotic and anti-inflammation role of insulin and crocin.Key Words: Apoptosis, Crocin, Diabetes, Inflammation, Insulin, TSP  相似文献   
87.
Tissue culture methods are useful in assessing the tolerance of various stresses due to the ease of controlling stress under in vitro conditions. This study aimed to investigate the response of sugarcane genotyps to drought stress using calli as a model system. For inducing sugarcane callus, the medium of Murashige and Skoog (MS) was used with different mannitol concentrations (100, 200, and 300 mM) to measure their effects on callus frequency, the day of callus initiation, embryogenic potential, relative growth rate (RGR), water and proline contents, K+ and Na+ contents, as well as the formation of shoot and roots for three sugarcane genotypes (e.g., GT 54-9, G 84-47, and pH 8013). The RAPD-PCR analysis was carried out using five oligonucleotide primers to identify the genetic variation among sugarcane genotypes. The results indicated that the degree of callus proliferation varied from 70 − 86%. The highest value of callus proliferation, PGR, shoot formation was recorded for the genotype GT 54-9 compared to the other two genotypes (G 84-47 and pH 8013). Calli treated with 100 mM mannitol showed the highest RGR, proline and waer contents for the genotype GT 54-9, while, those treated with 300 mM recorded the lowest values of these parameters for the genotype pH 8013. The genotype G 84-47 collected highest Na+ content, while the genotype pH 8013 collected highest K+ content. The results of this study recommend preference for GT 54-9 genotype, which is considered the most promising genotype, showing more tolerance to drought stress based on all studied traits.  相似文献   
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Biological Trace Element Research - To observe and compare the effects of healthy instruction and Zhiqi granules on lead, calcium, iron, and zinc levels in serum of children with moderately...  相似文献   
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