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Purpose: The aim of this study was to model the relationship between risk factors of postpartum depression and quality of life in Iranian women. Methods: In this study, 306 women were included as a sample. The study tools of the Edinburgh Postpartum Depression Inventory included items such as socioeconomic characteristics, recent pregnancy history and outcome, and Quality of Life Questionnaire (SF-12). SPSS software was used for data analysis and a significance value of 0.05 was considered. Results: Most participants were homemakers with no instances of abortion, no stillbirth, no history of depression, no preterm delivery, no difficulties during pregnancy, no difficulties during delivery, no unplanned pregnancy, no smoking during pregnancy, had family support during pregnancy and after delivery, type of delivery was cesarean, had a healthy baby and satisfaction with neonatal sex, and never or rarely experienced partner violence. Their mean age, years of education, living arrangements, and breastfeeding of participants respectively were 29.73±5.42, 14.64±1.96, 1.09±0.53, and 5.61±2.98. The prevalence of postpartum depression was 5.6%. According to the path analysis, living arrangements with β=0.73 had the most direct effect and occupation with β=0.69 had the most indirect effect on postpartum depression. Conclusions: According to the path analysis model, postpartum depression is affected by many factors such as age, years of education, occupation, living arrangements, and quality of life.  相似文献   
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Biomechanics and Modeling in Mechanobiology - Evolution of mechanical and structural properties in the Ascending Thoracic Aorta (ATA) is the results of complex mechanobiological processes. In this...  相似文献   
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Bradyrhizobia are common members of soil microbiomes and known as N2-fixing symbionts of economically important legumes. Many are also denitrifiers, which can act as sinks or sources for N2O. Inoculation with compatible rhizobia is often needed for optimal N2-fixation, but the choice of inoculant may have consequences for N2O emission. Here, we determined the phylogeny and denitrification capacity of Bradyrhizobium strains, most of them isolated from peanut-nodules. Analyses of genomes and denitrification end-points showed that all were denitrifiers, but only ~1/3 could reduce N2O. The N2O-reducing isolates had strong preference for N2O- over NO3-reduction. Such preference was also observed in a study of other bradyrhizobia and tentatively ascribed to competition between the electron pathways to Nap (periplasmic NO3 reductase) and Nos (N2O reductase). Another possible explanation is lower abundance of Nap than Nos. Here, proteomics revealed that Nap was instead more abundant than Nos, supporting the hypothesis that the electron pathway to Nos outcompetes that to Nap. In contrast, Paracoccus denitrificans, which has membrane-bond NO3 reductase (Nar), reduced N2O and NO3 simultaneously. We propose that the control at the metabolic level, favouring N2O reduction over NO3 reduction, applies also to other denitrifiers carrying Nos and Nap but lacking Nar.  相似文献   
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Amino acids (AA) as metal complexing agents have the ability to form relatively stable complexes with zinc (Zn) and thereby increase its availability for plants. In this study, the complexes of Zn(II), [Zn(L–L′)2] [where L–L′ = monoanion of arginine (Arg), glycine (Gly), glutamine (Gln), histidine (His), and methionine (Met)], were synthesized and characterized by different analytical techniques. The results of elemental analysis support the formation of Zn(II)–AA complexes (ZnAAC) with a 2:1 ligand-to-metal molar ratio. The computational results indicated that the AA ligands coordinated to the Zn(II) ion via their nitrogen and oxygen atoms and support the coordination mode obtained from IR spectroscopy. For the first time, the semiempirical calculations were also performed to investigate the passive uptake of ZnAAC by root cells. The proposed transport pathway indicated that ZnAAC can pass via plant root cell wall pores without any strict hindrances. The efficacy of ZnAAC as a Zn source was evaluated for two lettuce cultivars (Lactuca sativa L., cvs. ‘Lollo Bionda’ and ‘Lollo Rossa’) grown in nutrient solution. The results confirmed the higher efficacy of ZnAAC in supplying Zn for lettuce in comparison with ZnSO4. The synthesized ZnAAC also had a stimulating effect on root and shoot growth of both lettuce cultivars. According to the results, ZnAAC can be used as ecofriendly plant growth stimulators and sources of Zn to supply plants with readily available Zn.  相似文献   
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