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1.
The inorganic stannous-based perovskite oxide SrSnO3 has been utilized in various optoelectronic applications. Facilitating the synthesis process and engineering its properties, however, are still considered challenging due to several aspects. This paper reports on a thorough investigation of the influence of rare-earth (praseodymium) doping on the microstructural and optoelectronic properties of pure and Pr-doped SrSnO3 perovskite oxide thin films synthesized by a two-step simple chemical solution deposition route. Structural analysis indicated the high quality of the obtained phase and the alteration generated from the insertion of impurities. Surface scanning illustrated the formation of homogenous and crack-free SrSnO3 thin films with a nanorod morphology, with an augmentation in size as the dopant ratios increased. Optical properties analysis showed an enhancement in the samples optical absorption with wide-range bandgap tuning. First-principles calculations revealed the exchange interactions between the 3d–4f states and their impact on the electronic properties of the pristine material. Hall-effect measurements revealed an immense decrement in the resistivity of the films upon increment of doping ratios, passing from 7.3 × 10−2 Ω cm for the undoped sample to 4.8 × 10−2 Ω cm for 7% Pr content, while a reverse trend was observed on the carrier mobility, rising from 2.5 to 7.6 cm2 V−1 s−1 for 7% Pr content. The results emphasized the efficiency of the simple synthesis route to produce high-quality samples. The current findings will contribute to paving the way towards expanding the utilization of simple and cost-effective chemical solution deposition methods for the fast and large area growth of stannous-based perovskite oxides for optoelectronic applications.

Unraveling the optical, electronic and electrical properties of high-quality nanorod morphology spray-coated Pr-doped SrSnO3 perovskite oxide thin films.  相似文献   
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Delafossite materials are considered to be a promising range of transparent conductive oxides for optoelectronic applications. The complications that have held back their implementation in practical devices lie in the complex growth methods that are required and in the formation of undesirable secondary phases. Herein, a fast, simple, and low-cost deposition method allowing the deposition of high-quality 2H-CuFeO2 nanostructured thin films is employed. The effect of Sr doping on the properties of spray-coated CuFeO2 thin film annealed at 850 °C is reported. X-ray diffraction (XRD) analysis revealed the delafossite structures of all the samples corresponding to the 2H-CuFeO2 phase. The lattice spacing decreased with increasing substitution of Sr at the Cu site. Raman analysis further authenticated the structural results collected via XRD analysis. Surface scanning using field-emission scanning electron microscopy revealed the formation of nanostructured CuFeO2 thin film possessing high crystalline quality, with the nanocrystal size increasing as the dopant content was increased. Energy-dispersive X-ray analysis allowed the quantification of the elements content via determining the ratios of the main elements as well as the dopant content in each sample. The optical properties of the samples showed strong light absorption in the visible region with a decrease in the band gap values with Sr insertion. First-principles calculations using density functional theory (DFT) were conducted to strengthen the experimental findings regarding the nature of the bonds in the hexagonal lattice of the CuFeO2 compound and the effect of Sr doping on its characteristics. The electrical properties measured at room temperature revealed p-type conductivity with tunable resistivity, while the samples displayed increased electron mobility as a function of the dopant content. Consequently, our work introduced an efficient and cost-effective synthesis route for the preparation of high-quality nanostructured 2H-CuFeO2 thin films, paving the way to facilitate further device applications.

Facile synthesis of the challenging 2H-CuFeO2 delafossite nanostructured thin films is reported, and the effect of Sr doping is revealed experimentally and theoretically.  相似文献   
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The effects of vitamin E (Vit E) on brain derived neurotrophic factor (BDNF) and brain tissues oxidative damage as well as on learning and memory impairments in juvenile hypothyroid rats were examined. The rats were grouped as: (1) Control; (2) Propylthiouracil (PTU); (3) PTU-Vit E and (4) Vit E. PTU was added to their drinking water (0.05%) during 6 weeks. Vit E (20 mg/kg) was daily injected (IP). Morris water maze (MWM) and passive avoidance (PA) were carried out. The animals were deeply anesthetized and the brain tissues were removed for biochemical measurements. PTU increased the escape latency and traveled path in MWM (P?<?0.001). It also shortened the latency to enter the dark compartment of PA as well as the time spent in the target quadrant in probe trial of MWM (P?<?0.01-P?<?0.001). All the effects of PTU were reversed by Vit E (P?<?0.01-P?<?0.001). PTU administration attenuated thiol and BDNF content as well as the activities of superoxide dismutase (SOD) and catalase (CAT) in the brain tissues while increased molondialdehyde (MDA). Moreover, Vit E improved BDNF, thiol, SOD and CAT while diminished MDA. The results of the present study showed that Vit E improved BDNF and prevented from brain tissues oxidative damage as well as learning and memory impairments in juvenile hypothyroid rats.  相似文献   
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During particular periods of central nervous system (CNS) development, exposure to ethanol can decrease regional brain growth and can result in selective loss of neurons. Unfortunately, there are few effective means of attenuating damage in the immature brain. In this study, the possible antioxidant and neuroprotective properties of 17β-estradiol against ethanol-induced neurotoxicity was investigated. 17β-estradiol (600 μg/kg) was injected subcutaneously in postnatal day (PD) 4 and 5, 30 min prior to intraperitoneal injection of ethanol (6 g/kg) in rat pups. Ninety minutes after injection of ethanol, the activities of several antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (Gpx) in vermis of cerebellum were assayed. Thiobarbituric acid reactive substance (TBARS) levels were also measured as a marker of lipid peroxidation. Behavioral studies, including rotarod and locomotor activity tests were performed in PD 21-23 and histological study was performed after completion of behavioral measurements in postnatal day 23. The results of the present work demonstrated that ethanol could induce lipid peroxidation, increase TBARS levels and decrease glutathione peroxidase levels in pup cerebellum. We also observed that ethanol impaired performance on the rotarod and locomotor activities of rat pups. However, treatment with 17β-estradiol significantly attenuated motoric impairment, the lipid peroxidation process and restored the levels of antioxidants. Histological analysis also indicated that ethanol could decrease vermis Purkinje cell count and 17β-estradiol prevented this toxic effect. These results suggest that ethanol may induce lipid peroxidation in the rat pups cerebellum while treatment with 17β-estradiol improves motor deficits by protecting the cerebellum against ethanol toxicity.  相似文献   
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Antinociceptive, anti-inflammatory and acute toxicity of the aqueous infusion and ethanolic maceration extracts of the aerial parts of Zataria multiflora Boiss were studied in mice and rats. Antinociceptive activity was done using hot-plate and writhing tests. The effect of the extracts against acute inflammation was studied by vascular permeability increased by acetic acid and xylene induced ear edema in mice. The activity of the extracts against chronic inflammation was assessed by the cotton pellet test in rats. LD50 of the infusion and maceration extract was 3.85 and 3.47 g/kg, respectively. Intraperitoneal injection of both extracts in mice showed significant and dose-dependent antinociceptive activity. Naloxone, an opioid antagonist, pretreatment inhibited the antinociceptive activity of the extracts. The extracts exhibited antinociceptive activity against acetic acid induced writhing which was partially blocked by naloxone. Both extracts did not show remarkable activity against acute inflammation induced by acetic acid in mice. In the xylene ear edema, Z. multiflora Boiss extracts showed significant activity in mice. In the chronic inflammation the efficacy of the extracts was more than in acute inflammation. It is concluded that aqueous infusion and maceration of the aerial parts of Z. multiflora Boiss have antinociceptive effect and this may be mediated by opioid receptors. The extracts showed also anti-inflammatory effect against acute and chronic inflammation.  相似文献   
10.
Objective: Despite numerous experimental studies in the literature, there are few clinical trials regarding the effect of date palm pollen (DPP) supplementation on sexual function improvement. In the present study, we sought to evaluate the impact of DPP on female sexual function in Iranian non-menopausal women. Methods: Between October 2019 and December 2019, health centers in the city of Khalkhal, volunteers meeting the inclusion criteria were recruited in randomized clinical trials. Sixty-eight women were randomly stratified and assigned to one of the two study groups: placebo group (n = 35) and palm pollen group (n = 35), and received a starch or palm pollen capsule (300 mg per day), respectively, for 35 d. The Female Sexual Function Index (FSFI) instrument was used to assess female sexual function. Results: After DPP supplementation, the increase in desire, lubrication, and the overall score, was statistically significant compared to the placebo group (P = 0.002, P = 0.000, and P = 0.042; respectively); Whilst there was no significant differences in the remaining domains (arousal: P = 0.763; orgasm: P = 0.370; satisfaction: P =0.474; pain: P = 0.259). There was a statistically significant positive correlation between the coitus and preintervention levels of desire (r = 0.298, P = 0.038), arousal (r = 0.328, P = 0.021), lubrication (r = 0.361, P = 0.011), orgasm (r = 0.320, P = 0.025), satisfaction (r = 0.327, P = 0.022), and overall scores (r = 0.338, P = 0.018). Conclusion: This study suggests that DPP (300 mg supplementation for 35 d), given to non-menopausal women, could improve the lubrication and desire domains of FSFI.  相似文献   
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