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991.
The macromorphic properties of carbon nanotubes perform poorly because of their size limitations: nanosize in diameters and microsize in length. In this work, to realize these dual purposes, we first used an electrochemical method to tear the surface of multiwalled carbon nanotubes (MWCNTs) to anchor photonic Eu3+-complexes there. Through the polar reactive groups endowed by the tearing, the Eu3+-complexes coordinate at the defected structures, obtaining the Eu3+-complex-anchored, unzipped, multiwalled carbon nanotubes (E-uMWCNTs). The controllable surface-breaking retains the MWCNTs’ original, excellent mechanical properties. Then, to obtain the macromorphic structure with infinitely long fibers, a wet-spinning process was applied via the binding of a small quantity of polyvinyl alcohol (PVA). Thus, the wet-spun fibers with high contents of E-uMWCNTs (E-uMWCNT-Fs) were produced, in which the E-uMWCNTs took 33.3 wt%, a high ratio in E-uMWCNT-Fs. On the other hand, due to the reinforcing effect of E-uMWCNTs, the highest tensile strength can reach 228.2 MPa for E-uMWCNT-Fs. Meanwhile, the E-uMWCNT-Fs show high-efficiency photoluminescence and excellent media resistance performance due to the embedding effect of PVA on the E-uMWCNTs. Therefore, E-uMWCNT-Fs can exhibit excellent luminescence properties in aqueous solutions at pH 4~12 and in some high-concentration metal-ion solutions. Those distinguished performances promise outstanding innovations of this work.  相似文献   
992.
The excessive consumption of sugar-sweetened beverages (SSBs) has been proven to be critical for obesity among preschoolers. This study aimed to describe the SSB consumption rates among preschoolers in the Dongcheng District of Beijing, China, and to explore the association between obesogenic environmental determinants and consumption. We applied a stratified cluster sampling method and recruited 3057 primary caregivers of preschoolers in June 2019 to participate in the survey. The caregivers reported their children’s consumption rates of six categories of SSBs and their exposure rates to SSB-related obesogenic environments. The associations between them were tested using multivariate logistic regression models. The mean (SD) age of the children was 5.6 (0.6) years and nearly half (48.3%) were girls. About 84.5% of the children had consumed SSBs over the past three months, and sugar-sweetened milk beverages had the highest consumption rate. Higher exposure to advertisements for the corresponding SSB categories in children, higher frequency rates of consuming SSBs and of taking children to fast-food restaurants in caregivers, and lower frequency rates of reading the Nutrition Facts Panels by caregivers were associated with higher SSB consumption rates among children (p < 0.05 in all of the SSB categories investigated, except for the Nutrition Facts Panel reading behaviors for the sports and energy beverages). SSB consumption among preschoolers is of concern, and comprehensive policy actions and education are urgently needed.  相似文献   
993.
Background: Emergency cesarean section (EMCS) and breastfeeding difficulties increase the risk of postpartum depressive (PPD) symptoms. Early initiation of breastfeeding (EIBF) may not only alleviate PPD symptoms but also facilitate subsequent breastfeeding success. EMCS is a risk factor for not practicing EIBF. Therefore, it is important to understand the relationship between EMCS, EIBF, and PPD symptoms. Methods: We conducted a prospective cohort study in three areas of China. At baseline, a total of 965 mothers completed electronic questionnaires within 72 h postpartum. Women were screened for PPD symptoms using the Edinburgh Postpartum Depression Scale (EPDS). Multivariate logistic regression was used to identify the determinants of PPD symptoms. Mediation analysis was used to determine if EIBF mediated the relationship between delivery mode or breastfeeding education source and PPD symptoms. Results: The prevalence of EIBF was 40.6%; 14% of 965 mothers experienced EMCS, and 20.4% had PPD symptoms. The risk factors for developing PPD symptoms were excessive gestational weight gain (adjusted odds ratio [aOR] = 1.55, confidence interval [95% CI]: 1.03–2.33, p = 0.037) and EMCS (aOR = 2.05, 95% CI: 1.30–3.25, p = 0.002). The protective factors for developing PPD symptoms were monthly household income over CNY 10000 (aOR = 0.68, 95% CI: 0.47–0.97, p = 0.034), EIBF (aOR = 0.49, 95% CI: 0.34–0.72, p < 0.001), and prenatal breastfeeding education from nurses (aOR = 0.46, 95% CI: 0.29–0.73, p = 0.001). EIBF indirectly affected PPD symptoms in patients who had undergone EMCS (percentage mediated [PM] = 16.69, 95% CI: 7.85–25.25, p < 0.001). The source of breastfeeding education through EIBF also affected PPD symptoms (PM = 17.29, 95% CI: 3.80–30.78, p = 0.012). Conclusion: The association between EMCS on PPD symptoms was mediated by EIBF. By providing breastfeeding education, nurses could also help alleviate PPD symptoms.  相似文献   
994.
背景:腰椎间盘突出症的中西医结合治疗效果较好。 目的:全面综述腰椎间盘突出症中医辨证分型与蛋白质组学相关的研究。 方法:检索万方、清华同方等中文数据库及Pubmed数据库2001-01/2010-12的相关文章,中文检索词为“中医证型、蛋白质组学、腰椎间盘突出症”,英文检索词为“syndrome types, traditional Chinese medicine, protcomics, lumbar intervertebral disk protrusion”。纳入腰椎间盘突出症血清蛋白质组学研究及蛋白质组学、中医分型与中医药3者关联的研究,排除重复研究及Meta分析类文章。 结果与结论:计算机检索得到361篇文献,中文79篇,英文282篇,阅读标题与摘要进行筛选,排除与此文无关的文献。对29个符合要求的研究进行综述。研究认为,部分疾病的中医分型与血清蛋白质组学有关,机体某些特异性标志蛋白表达可能与椎间盘退变相关。腰椎间盘突出症与中医血瘀证、湿热证、寒湿证等证型的关联性得到了部分实验及临床的验证,但缺乏蛋白质组学相关性研究。  相似文献   
995.
996.
背景:国内外对骨形态发生蛋白7的研究倾向于其在组织工程方面的应用,但是骨形态发生蛋白7除具有很强的骨诱导活性之外,还影响动物生殖系统的生长发育及生理功能,如何在充分发挥其骨诱导活性的同时,避免其他生物学作用,是骨组织工程领域面临的一个难题。 目的:观察人工合成的新型骨形态发生蛋白7多肽对骨髓基质干细胞增殖、成骨分化及矿化等生物学行为影响。 方法:分离培养大鼠骨髓基质干细胞并用流式细胞仪进行鉴定。将传至第3代的骨髓基质干细胞分为实验组和对照组,实验组在培养基加入终质量浓度为100 mg/L的骨形态发生蛋白7多肽,对照组不加多肽。分别在培养的2,4,6,8,10 d对各组细胞进行MTT检测,评价其增殖情况;培养7,14 d后,通过检测细胞内钙含量和碱性磷酸酶活性评价其成骨分化情况,并进行钙黄绿素染色观察其矿化情况。 结果与结论:原代培养大鼠骨髓基质干细胞生长良好,其纯度达到91.5%。细胞增殖实验显示骨髓基质干细胞在实验组和对照组中均增殖良好,差异无显著性意义(P > 0.05);诱导培养7 d和14 d后,实验组碱性磷酸酶活性及钙含量显著高于对照组(P < 0.05),实验组细胞矿化明显强于对照组。实验结果表明新型骨形态发生蛋白7多肽对骨髓基质干细胞增殖没有显著影响,但可以促进其向成骨方向分化及矿化。  相似文献   
997.
背景:研究表明小檗碱可用于治疗2型糖尿病,但小檗碱治疗糖尿病胰岛素抵抗尤其是肝脏脂诱性胰岛素抵抗的分子机制仍不明确。 目的:观察小檗碱对2型糖尿病中国地鼠模型肝脏过氧化物酶体增殖体激活受体及其靶基因表达的影响。 方法:以高脂饮食及结合小剂量链脲菌素的方法建立胰岛素抵抗和2型糖尿病中国地鼠模型。建模后随机分成4组:对照组给予普通饮食,胰岛素抵抗组给予高脂饮食,2型糖尿病组给予高脂饮食+小剂量链脲菌素,2型糖尿病小檗碱治疗组给予高脂饮食+小剂量链脲菌素+小檗碱,治疗9周。 结果与结论:实时定量PCR结果显示与对照组相比,胰岛素抵抗及2型糖尿病组地鼠肝脏过氧化物酶体增殖体激活受体α,β/d,酰基辅酶A氧化酶,肉碱棕榈酰转移酶1和中链酰基辅酶A脱氢酶的表达降低(P < 0.05),而固醇调节元件结合蛋白1c,2,过氧化物酶体增殖体激活受体γ,脂蛋白脂酶,脂肪酸转运者(FAT/CD36)和脂肪酸结合蛋白(ap2)的表达增加(P < 0.05)。结果证实,小檗碱可改善胰岛素抵抗,并逆转了氧化物酶体增殖体激活的受体及其靶基因表达的改变,小檗碱治疗2型糖尿病地鼠脂诱性胰岛素抵抗的分子机制与氧化物酶体增殖体激活的受体及其靶基因表达的改变相关。  相似文献   
998.
学术背景:渐进性肌肉放松是一种放松疗法,国外己将这一技术应用于多种心身疾病的临床治疗中,有效地帮助患者减轻负性情绪,适应治疗,改善生理功能。国内对这一技术也日益重视,但相关研究尚不多。 目的:对渐进性肌肉放松的概念、原理、历史发展予以介绍,侧重回顾关于渐进性肌肉放松在心身疾病临床治疗中的应用。 检索策略:由心理学及心身疾病研究人员应用计算机检索PubMed数据库(http://www.ncbi.nlm.nih.gov/sites/entrez)1985-01/2007-10有关渐进性肌肉放松训练临床治疗应用方面的文献,检索词 “Progressing Relaxation, Progressive Muscle Relaxation Training, Intervention, Treatment, relaxation and relaxation effect”等,限定语言种类为English。同时检索中国科技期刊全文数据库(http://www.edu.cnki.net)1990-01/2007-10有关渐进性肌肉放松训练临床治疗应用方面的文献,检索词 “渐进性肌肉放松,渐进性放松,干预”,限定语言种类为中文。初步检索的文献量为外文636篇,中文15篇。对资料进行初审,纳入标准:渐进性肌肉放松训练的概念、原理、发展及其在心身疾病临床治疗方面的应用。排除标准:重复性研究。 文献评价:根据标准筛选共检索到文献32篇,其中外文23篇,中文文献9篇;3篇为综述,其余均为临床与实验研究。 资料综合:内容包括以下几方面:①渐进性肌肉放松训练对患者情绪状态的影响。②渐进性肌肉放松对患者生理生化指标的影响。③渐进性肌肉放松对患者生活质量的影响。④渐进性肌肉放松与其他心理干预方法的联合使用。 结论:渐进性肌肉放松训练简单易行、无副作用、不需专门的仪器,可以随时随地进行。既往研究表明,此技术能快速有效地降低多种心身疾病患者的应激水平,改善情绪状态,减轻疼痛和恶心呕吐,改善心血管和免疫系统功能,提高远期生活质量。但目前对渐进性肌肉放松疗法的效果仍有争议。  相似文献   
999.
目的探讨血浆同型半胱氨酸与前部缺血性视神经病变发病的相关性。方法对31例34眼前部缺血性视神经病变(anterior ischemic optic neuropathy,AION)组和对照组进行血浆同型半胱氨酸(homocysteine hcy)、叶酸(folic acid FA)和氧化型低密度脂蛋白(oxidized low density liportotenin oxLDL)水平进行检测。结果 AION组hcy水平(21.4±5.3)μmol/L高于对照组(9.3±3.4)μmol/L,FA水平(6.2±3.7)μg/mL低于对照组(11.3±4.2μg/mL),oxLDL浓度(46.6±5.5U/mL)明显高于对照组32.2±6.8U/mL),2组比较差异有统计学意义(P<0.05);相关性比较,HCY的升高与oxLDL的升高呈正相关(r=0.87,P=0.007),与FA的水平呈负相关(r=-0.92,P=0.003)。结论 HCY的升高可能是AION的重要发病因素。  相似文献   
1000.
ObjectiveTo observe the association between exposure to midazolam within 24 hours prior to delirium assessment and the risk of delirium.MethodsWe performed a systematic cohort study with two sets of cohorts to estimate the relative risks of outcomes among patients administered midazolam within 24 hours prior to delirium assessment. Propensity score matching was performed to generate a balanced 1:1 matched cohort and identify potential prognostic factors. The outcomes included the odds of delirium, mortality, length of intensive care unit stay, length of hospitalization, and odds of being discharged home.ResultsA total of 78,364 patients were included in this study, of whom 22,159 (28.28%) had positive records. Propensity matching successfully balanced covariates for 9348 patients (4674 per group). Compared with no administration of midazolam, midazolam administration was associated with a significantly higher risk of delirium, higher mortality, and a longer intensive care unit stay. Patients treated with midazolam were relatively less likely to be discharged home. There was no significant difference in hospitalization duration.ConclusionsMidazolam may be an independent risk factor for delirium in critically ill patients.  相似文献   
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