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71.
In order to study the effect of mycorrhizal fungi (inoculated and non-inoculated) and heavy metals stress [0, Pb (150 and 300 mg/kg) and Cd (40 and 80 mg/kg)] on pot marigold (Calendula officinalis L.), a factorial experiment was conducted based on a randomized complete block design with 4 replications in Research Greenhouse of Department of Horticultural Sciences, University of Tehran, Iran, during 2012–2013. Plant height, herbal and flower fresh and dry weight, root fresh and dry weight and root volume, colonization percentage, total petal extract, total petal flavonoids, root and shoot P and K uptakes, and Pb and Cd accumulations in root and shoot were measured. Results indicated that with increasing soil Pb and Cd concentration, growth and yield of pot marigold was reduced significantly; Cd had greater negative impacts than Pb. However, mycorrhizal fungi alleviated these impacts by improving plant growth and yield. Pot marigold concentrated high amounts of Pb and especially Cd in its roots and shoots; mycorrhizal plants had a greater accumulation of these metals, so that those under 80 mg/kg Cd soil?1 accumulated 833.3 and 1585.8 mg Cd in their shoots and roots, respectively. In conclusion, mycorrhizal fungi can improve not only growth and yield of pot marigold in heavy metal stressed condition, but also phytoremediation performance by increasing heavy metals accumulation in the plant organs.  相似文献   
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Fleas are important vectors of diseases such as murine typhus, tularaemia, hymenolepiasis and plague. The presence of active foci and history of human‐ and flea‐transmitted plague in northwest Iran prompted the present group to collect and identify fleas from human and livestock dwellings across West Azerbaijan Province. Adult fleas were collected and identified using routine taxonomic keys. Species designation was confirmed by sequencing the cytochrome oxidase subunit I (COI). Of the collected specimens (n = 989), 104 were collected off‐host (30 from human dwellings and 74 in light traps) and the rest were found on hosts (107 on animals and 778 by human bait). Of these fleas, 394 (40%) were male and 595 (60%) were female. The collected specimens belonged to the species Ctenocephalides canis, Ctenocephalides felis, Ctenocephalides orientis and Pulex irritans (all: Siphonaptera: Pulicidae). The amplified COI fragment, in addition to confirming the morphological identification of species, showed good efficacy in separating the different species in the phylogenetic analysis. In addition to the identification of fleas from human and livestock dwellings using morphological and molecular characteristics, the current paper represents the first report of the presence of C. orientis in northwest Iran. This finding suggests that changing climate conditions may have expanded the distribution of this species.  相似文献   
74.
Plasmonics - In this paper, some biological sensors based on surface plasmon resonance are proposed at visible and near-infrared wavelengths and their performance is improved. The structure of...  相似文献   
75.
Burrell K  Hill RP  Zadeh G 《PloS one》2012,7(6):e38366
Radiation therapy (RT) is a widely accepted treatment strategy for many central nervous system (CNS) pathologies. However, despite recognized therapeutic success, significant negative consequences are associated with cranial irradiation (CR), which manifests months to years post-RT. The pathophysiology and molecular alterations that culminate in the long-term detrimental effects of CR are poorly understood, though it is thought that endothelial injury plays a pivotal role in triggering cranial injury. We therefore explored the contribution of bone marrow derived cells (BMDCs) in their capacity to repair and contribute to neo-vascularization following CR. Using high-resolution in vivo optical imaging we have studied, at single-cell resolution, the spatio-temporal response of BMDCs in normal brain following CR. We demonstrate that BMDCs are recruited specifically to the site of CR, in a radiation dose and temporal-spatial manner. We establish that BMDCs do not form endothelial cells but rather they differentiate predominantly into inflammatory cells and microglia. Most notably we provide evidence that more than 50% of the microglia in the irradiated region of the brain are not resident microglia but recruited from the bone marrow following CR. These results have invaluable therapeutic implications as BMDCs may be a primary therapeutic target to block acute and long-term inflammatory response following CR. Identifying the critical steps involved in the sustained recruitment and differentiation of BMDCs into microglia at the site of CR can provide new insights into the mechanisms of injury following CR offering potential therapeutic strategies to counteract the long-term adverse effects of CR.  相似文献   
76.
The effects of cosmic radiation in single cells, organic tissues and electronics are a major concern for space exploration and manned missions. Standard heavy ions radiation tests employ ion cocktails with energy of the order of 10 MeV per nucleon and with a linear energy transfer ranging from a few MeV cm(2) mg(-1) to hundreds of MeV cm(2) mg(-1). In space, cosmic rays show significant fluxes at energies up to the order of GeV per nucleon. The present work aims at investigating single event damage due to low-, high- and very-high-energy ions. The European Space Agency reference single event upset monitor data are used to support the discussion. Finally, the effect of ionization induced directly by primary particles and ionization induced by recoils produced in an electronic device is investigated for different types of devices.  相似文献   
77.
Spontaneously migrating Walker carcinosarcoma cells usually form lamellipodia at the front. Combined treatment with 10(-5)M colchicine and 10(-7)M latrunculin A produces large defects in the cortical F-actin layer at the leading front and suppresses lamellipodia. However, the cortical actin layer at the rear is intact and shows myosin IIA accumulation. These cells, showing no or little detectable cortical F-actin at the front and no morphologically recognisable protrusions, migrate faster than control cells with lamellipodia and an intact cortical actin layer. This documents that the cortical actin layer or actin-powered force generation at the front is redundant for locomotion. Colchicine and latrunculin A have synergistic effects in compromising the cortical layer at the front and in increasing the speed of locomotion, but antagonistic effects on the relative amount of F-actin per cell. Colchicine but not latrunculin A, can increase the proportion of polarised and locomoting cells under appropriate conditions. Locomotion and polarity of cells treated with latrunculin A and colchicine is inhibited at latrunculin A concentrations >10(-7)M, by the myosin inhibitor BDM or the ROCK inhibitor Y-27632. Colchicine and Y-27632 have antagonistic effects on polarity and the speed of locomoting cells. The data show that locomotion of metazoan cells, which normally form lamellipodia, can be driven by actomyosin contraction behind the front (cell body, uropod). They are best compatible with a cortical contraction/frontal expansion model, but they are not compatible with models implying that actin polymerisation or actomyosin contraction at the front drive locomotion of the cells studied.  相似文献   
78.
This study was conducted to evaluate the effects of selenium supplementation on gene expression related to insulin and lipid in infertile women with polycystic ovary syndrome (PCOS) candidate for in vitro fertilization (IVF). This randomized double-blind, placebo-controlled trial was conducted among 40 infertile women with PCOS candidate for IVF. Subjects were randomly allocated into two groups to intake either 200-μg selenium (n = 20) or placebo (n = 20) per day for 8 weeks. Gene expression levels related to insulin and lipid were quantified in lymphocytes of women with PCOS candidate for IVF with RT-PCR method. Results of RT-PCR demonstrated that after the 8-week intervention, compared with the placebo, selenium supplementation upregulated gene expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) (1.06 ± 0.15-fold increase vs. 0.94 ± 0.18-fold reduction, P = 0.02) and glucose transporter 1 (GLUT-1) (1.07 ± 0.20-fold increase vs. 0.87 ± 0.18-fold reduction, P = 0.003) in lymphocytes of women with PCOS candidate for IVF. In addition, compared with the placebo, selenium supplementation downregulated gene expression of low-density lipoprotein receptor (LDLR) (0.88 ± 0.17-fold reduction vs. 1.05 ± 0.22-fold increase, P = 0.01) in lymphocytes of women with PCOS candidate for IVF. We did not observe any significant effect of selenium supplementation on gene expression levels of lipoprotein(a) [LP(a)] in lymphocytes of women with PCOS candidate for IVF. Overall, selenium supplementation for 8 weeks in lymphocytes of women with infertile PCOS candidate for IVF significantly increased gene expression levels of PPAR-γ and GLUT-1 and significantly decreased gene expression levels of LDLR, but did not affect LP(a).Clinical trial registration number: http://www.irct.ir: IRCT201704245623N113.  相似文献   
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This study was carried out to investigate the effects of chromium intake on glycemic control, markers of cardio-metabolic risk, and oxidative stress in infertile polycystic ovary syndrome (PCOS) women candidate for in vitro fertilization (IVF). This randomized double-blind, placebo-controlled trial was done among 40 subjects with infertile PCOS candidate for IVF, aged 18–40 years old. Individuals were randomly allocated into two groups to take either 200 μg/day of chromium (n?=?20) or placebo (n?=?20) for 8 weeks. Biochemical parameters were assessed at baseline and at end-of-trial. Compared with the placebo, taking chromium supplements led to significant reductions in fasting plasma glucose (??2.3?±?5.7 vs. +?0.9?±?3.1 mg/dL, P?=?0.03), insulin levels (??1.4?±?2.1 vs. +?0.4?±?1.7 μIU/mL, P?=?0.004), homeostatic model of assessment for insulin resistance (??0.3?±?0.5 vs. +?0.1?±?0.4, P?=?0.005), and a significant increase in quantitative insulin sensitivity check index (+?0.004?±?0.008 vs. ??0.001?±?0.008, P?=?0.03). In addition, chromium supplementation significantly decreased serum triglycerides (??19.2?±?33.8 vs. +?8.3?±?21.7 mg/dL, P?=?0.004), VLDL- (??3.8?±?6.8 vs. +?1.7?±?4.3 mg/dL, P?=?0.004) and total cholesterol concentrations (??15.3?±?26.2 vs. ??0.6?±?15.9 mg/dL, P?=?0.03) compared with the placebo. Additionally, taking chromium supplements was associated with a significant increase in plasma total antioxidant capacity (+?153.9?±?46.1 vs. ??7.8?±?43.9 mmol/L, P?<?0.001) and a significant reduction in malondialdehyde values (?0.3?±?0.3 vs. +?0.1?±?0.2 μmol/L, P?=?0.001) compared with the placebo. Overall, our study supported that chromium administration for 8 weeks to infertile PCOS women candidate for IVF had beneficial impacts on glycemic control, few variables of cardio-metabolic risk, and oxidative stress.  相似文献   
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