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991.
目的 探讨实习护生角色宽度自我效能现状及其影响因素,为实施针对性干预,提升实习护生群体角色宽度自我效能水平提供参考。
方法 采用一般资料调查表、角色宽度自我效能量表和心理资本量表对湖南省5所医院535名实习护生进行问卷调查。
结果 实习护生角色宽度自我效能总分为(24.27±6.64)分,心理资本总分(101.44±18.03)分;分层回归显示,获奖经历、兴趣与专业的匹配程度、医院氛围及敏感人格对实习护生角色宽度自我效能产生影响(均P<0.05),心理资本可独立解释角色宽度自我效能31.5%的变异。
结论 实习护生角色宽度自我效能水平较高,受多种因素影响,心理资本可正向影响实习护生角色宽度自我效能,教师和护理管理者可采取有效措施提高护生心理资本,进而提高角色宽度自我效能,稳定和发展护理队伍。 相似文献
992.
993.
Objective: To evaluate the effects of Xiaojin Pill(小金丸) in the treatment of Peyronie's disease(PD) in a rat model. Methods: Twenty-four male Sprague-Dawley rats were randomly divided into four groups with 6 in each: sham operation, PD model, vehicle control and Xiaojin Pill groups. The rats in the sham operation group received penile tunica albsginea(TA) injection with 50 μL vehicle, while the rats in the other 3 groups received 50 μL penile TA injection of 50 μg transforming growth factor(TGF)-β1. Forty-two days after the injection, rats in the vehicle control and Xiaojin Pill groups received 0.5 mL water and Xiaojin Pill solution(107 mg/kg of body weight), respectively by gavage for 28 days, while those in the sham operation and PD model groups did not receive any intervention. After intervention, the expressions of matrix metalloproteinase 2/9(MMP2/9), nitric oxidesynthase(NOS), superoxide dismutase(SOD) and malondialdehyde(MDA) were measured. Results: Rats in the PD model and vehicle control groups presented obvious fibrosis in corpus cavernosum(CC) and demonstrated a significantly increased expressions of MMP2 and MMP9 in the CC compared with the sham operation group(all P0.01). In contrast, the expressions of MMP2 and MMP9 in the Xiaojin Pill group were significantly down-regulated(both P0.01). In addition, the levels of NOS and MDA in CC were significantly increased while the activity of SOD was decreased in the PD model and vehicle control groups compared with the sham operation group(al P0.01). After Xiaojin Pil treatment, the levels of MDA, NOS and SOD appeared to be corrected(al P0.01). Conclusions: Xiaojin Pill could reduce fibrosis in the CC by decreasing the expressions of MMPs, NOS and MDA, and by increasing the activity of SOD. Therefore, Xiaojin Pill might be a therapeutic option for PD. 相似文献
994.
995.
A novel mutation in FBN1 gene in autosomal dominant Marfan syndrome and macular degeneration in a Chinese consanguineous family
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AIM: To report a novel mutation in FBN1 gene in a Chinese consanguineous family with common Marfan syndrome (MFS) phenotype and an unusual bilateral macular degeneration.
METHODS: Ophthalmic, cardiovascular and systemic examinations were performed, and genomic DNA extracted from all living family members. The 24-32 exon mutations of FBN1 gene were screened by Sanger Sequencing in all family members and 100 unrelated healthy Chinese individuals.
RESULTS: In the four-generation family, classic MFS phenotypes were observed in all 5 patients, 2 of them had peculiar phenotype of bilateral macular degeneration. Mutation screening in FBN1 identified a heterozygous missense mutation (c.3932A>G, p.Y1311C) with co-segregation. This mutation was found with the MFS phenotypes in all 5 patients but not in unaffected members or unrelated controls.
CONCLUSION: A Chinese consanguineous MFS family with uncommon bilateral macular degeneration and an unreported c.3932A>G mutation in FBN1 was identified. Our finding expands the FBN1 mutation spectrum and its possible role in the pathogenesis of Marfan syndrome. 相似文献
996.
Astragalus polysaccharide improves insulin sensitivity in KKAy mice: Regulation of PKB/GLUT4 signaling in skeletal muscle 总被引:1,自引:0,他引:1
Ethnopharmacological relevance
Astragalus polysaccharide (APS) is an important bioactive component of Astragalus membranaceus Bunge (Leguminosae) that has been used in traditional Chinese medicine for treating diabetes.Aim of the study
To study the mechanisms by which APS ameliorates diabetes, we examined whether treatment with APS improves insulin sensitivity in insulin-resistant mice and whether this is associated with an improvement of dysregulated protein kinase B and glucose transporter 4 expressions in skeletal muscle.Methods
APS (700 mg kg−1 day−1) or vehicle was administered to 12-week-old diabetic KKAy and nondiabetic C57BL/6J mice for 8 weeks. Changes in body weight, blood glucose level, insulin resistance index, and oral glucose tolerance were routinely evaluated. The expressions of protein kinase B and glucose transporter 4 in skeletal muscle tissues were determined with Western blot.Results
KKAy mice developed persistent hyperglycemia, impaired glucose tolerance and insulin resistance. Insulin-stimulated protein kinase B phosphorylation and glucose transporter 4 translocation were significantly decreased in KKAy compared to age-matched C57BL/6J mice. APS treatment ameliorated hyperglycemia and insulin resistance. Although the content of protein kinase B and glucose transporter 4 in KKAy skeletal muscle were not affected by APS, insulin-induced protein kinase B Ser-473 phosphorylation and glucose transporter 4 translocation in skeletal muscle were partially restored by APS treatment. In contrast, APS did not have any effect on C57BL/6J mice.Conclusions
These results indicate that APS can regulate part of the insulin signaling in insulin-resistant skeletal muscle, and that APS could be a potential insulin sensitizer for the treatment of type 2 diabetes. 相似文献997.
998.
Different concentrations of hyaluronic acid eye drops for dry eye syndrome: a systematic review and Meta-analysis
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Xiao-Wei Ouyang Sheng Fang Yun-Min Yi Shi-Peng Zou Qi-Yu Hu Zi-Xuan Huang Qing-Xia Li Jin-Yan Luo 《国际眼科》2024,17(6):1110-1119
AIM: To compare high or low concentration of hyaluronic acid eye drops (HY) for dry eye syndromes (DES).
METHODS: Randomized controlled trials (RCTs) comparing various concentrations of HY were searched in PubMed, Embase, Web of Science, Cochrane, SinoMed, CNKI, Wanfang Database, CQVIP, and Chinese journals databases between inception and July 2023. Pooled standardized mean differences (SMD) or weighted mean difference (WMD) with 95% confidence intervals (CI) from RCTs evaluating Schirmer’s I test (SIT), corneal fluorescein staining score (CFS), tear breakup time (TBUT), DES score (DESS), and Ocular Surface Disease Index (OSDI) were calculated. Sensitivity analysis, Egger’s test and Meta-regression analysis were performed for all indicators.
RESULTS: We conducted a Meta-analysis of 10 RCTs that met the inclusion criteria, involving 1796 cases. High-concentrations group significantly improved the outcome of CFS according to random effects modelling (SMD, -3.37; 95%CI, -5.25 to -1.48; P=0.0005). The rest of the results were not statistically significant, including indicators such as SIT, TBUT, DESS and OSDI.
CONCLUSION: For dry eyes with positive corneal staining, a high concentration of HY is recommended, whereas in other cases, a high concentration of HY does not offer a more pronounced advantage over a low concentration of HY in the treatment of dry eyes. 相似文献
999.
1000.
Junhui Wang Qi Fu Jiaxing Yu Huangsheng Yang Zhengping Hao Fang Zhu Gangfeng Ouyang 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(3)
The Fenton-like process catalyzed by metal-free materials presents one of the most promising strategies to deal with the ever-growing environmental pollution. However, to develop improved catalysts with adequate activity, complicated preparation/modification processes and harsh conditions are always needed. Herein, we proposed an ultrafast and facile strategy to convert various inefficient commercial nanocarbons into highly active catalysts by noncovalent functionalization with polyethylenimine (PEI). The modified catalysts could be in situ fabricated by direct addition of PEI aqueous solution into the nanocarbon suspensions within 30 s and without any tedious treatment. The unexpectedly high catalytic activity is even superior to that of the single-atom catalyst and could reach as high as 400 times higher than the pristine carbon material. Theoretical and experimental results reveal that PEI creates net negative charge via intermolecular charge transfer, rendering the catalyst higher persulfate activation efficiency.Due to the rapid pace of urbanization and heavy industrialization, organic pollutants in the aquatic environment have become a serious and ubiquitous problem on a global scale. The Fenton or Fenton-like process, an effective approach to generate active species by activating oxidizing agents for the elimination of a wide range of organic pollutants, has been regarded as a promising strategy to deal with the ever-growing environmental pollution (1, 2). Among the various oxidants, persulfate (S2O82−; PS), as an inexpensive, environmentally friendly, and easily handled strong oxidant (E0 = 2.1 V), has been widely utilized in various fields, including water oxidation (3, 4), chemical analysis (5, 6), microbial/microfluidic fuel cell (7, 8), organic (molecular/polymer) synthesis (9, 10), and environmental remediation (11, 12), ranging from bench-scale experiments to industrial processes. Since originally introduced for in situ soil and groundwater remediation in the late 1990s to overcome the technical limitations of hydrogen peroxide (H2O2) (13), the PS-based Fenton-like system has drawn significant attention as an alternative to the H2O2-based Fenton process in water/wastewater treatment, owing to the advantages including high oxidation capacity under circumstance conditions (at neutral pH or with background constituents), high-yield radical production, low cost of storage/transportation, and various activation strategies (11, 12). Over the past few years, various transition-metal-based materials have been widely investigated as Fenton-like catalysts for PS activation (14–16). In terms of sustainable development, metal-based catalysts suffer from prohibitive cost, scarcity in nature, and secondary pollution. In this regard, metal-free carbon materials such as carbon nanotubes (CNTs) and graphene are promising candidates, owing to their unique structures and properties (17–19).In general, the efficiencies of pristine nanocarbons in activation of PS are very low (19, 20). Researchers have successively explored different strategies to boost the PS activation by regulating the local electronic environment of carbocatalysts, such as covalent doping of suitable heteroatoms (e.g., N or S) (17, 21, 22), introduction of intrinsic defects on the edge (23, 24), and construction of specific structure (25). However, the existing strategies usually involve complicated preparation processes (the usage of templates), special equipment (plasma devices), and/or harsh reaction conditions (high-temperature annealing under special atmosphere), which are time-consuming and more laborious, greatly increasing the financial costs for large-scale production and industrialization (22, 25, 26).In principle, PS activation relies mainly on the cleavage of peroxyl bonds induced by electron transfer from catalysts, and the electron-transfer efficiency could be modulated by tuning the electron states (i.e., charge/spin density or density of state) of the catalysts (14, 18, 27). Recently, various polyelectrolytes, including polyethylenimine (PEI), have been utilized to tune the surface electronic structures of electrodes in electronic/electrochemical applications (28–31). Inspired by these observations, herein, we explored an ultrafast and facile approach to transform inefficient commercial nanocarbons into highly active, metal-free catalysts for PS activation by noncovalent functionalization with PEI (SI Appendix, Scheme S1). Density functional theory (DFT) calculations, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and Kelvin probe force microscopy (KPFM) revealed that PEI could tune the local electronic environment of carbon atoms through the intermolecular electron donation from PEI to nanocarbons. As a result, the activities of the modified catalysts could be greatly enhanced and reach as high as 400 times higher than the pristine carbon material. Moreover, PEI-nanocarbon membranes were further in situ fabricated and applied to treat wastewater in a continuous-flow mode, revealing the feasibility of its practical application. 相似文献