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991.
Rapid and correct diagnosis of acute myocardial infarction (AMI) plays a crucial role in saving patients'' life. Although some biomarkers (such as cardiac troponin and creatine kinase) are available for AMI diagnosis so far, there is still a clinical need for novel biomarkers, which can reliably rule in or rule out AMI immediately on admission. Circulating microRNAs (miRNAs) are a potential choice for novel biomarkers in AMI diagnosis and prognosis with high sensitivity and specificity. Circulating microRNAs are endogenous miRNAs that are detectable in whole blood, serum, or plasma in a highly stable form. Until now, around 20 circulating miRNAs were reported to be closely associated with AMI. In this minireview, we summarized recent available data on the correlation between circulating miRNAs and AMI. Some miRNAs, such as miR-208, miR-499, miR-133, and miR-1, were given special attention, since they may have a potential prospect in diagnosis and prognosis of AMI. 相似文献
992.
993.
目的研究8.5%甲嘧·高氯氟卫生杀虫泡腾片剂的加工工艺、药效及其质量控制。方法选用广谱性的杀虫有效成分甲基嘧啶磷和高效氯氟氰菊酯混配组成,计量后压片。结果研制了8.5%甲嘧.高氯氟卫生杀虫泡腾片,适用于背负式、手动储压式、机动喷雾器、水雾机,可广泛用于宾馆、饭店等有卫生要求的场所防治蚊蝇和蟑螂等害虫,1L水加2片。结论 8.5%甲嘧·高氯氟卫生杀虫泡腾片剂作为一种新剂型具有高效、便捷、量化的特点。 相似文献
994.
为弥补"以学科为中心"的教学不足,以器官系统为中心的教学成为医学教学改革的趋势。本研究以"运动系统"为例,从教学实施、教学质量监督、配套考核制度和教学成效四方面探讨器官系统为中心的整合医学教学模式的实践情况。 相似文献
995.
Accelerated ferumoxytol‐enhanced 4D multiphase,steady‐state imaging with contrast enhancement (MUSIC) cardiovascular MRI: validation in pediatric congenital heart disease 下载免费PDF全文
Ziwu Zhou Fei Han Stanislas Rapacchi Kim‐Lien Nguyen Daniel Z. Brunengraber Grace‐Hyun J. Kim J. Paul Finn Peng Hu 《NMR in biomedicine》2017,30(1)
The purpose of this work was to validate a parallel imaging (PI) and compressed sensing (CS) combined reconstruction method for a recently proposed 4D non‐breath‐held, multiphase, steady‐state imaging technique (MUSIC) cardiovascular MRI in a cohort of pediatric congenital heart disease patients. We implemented a graphics processing unit accelerated CS‐PI combined reconstruction method and applied it in 13 pediatric patients who underwent cardiovascular MRI after ferumoxytol administration. Conventional breath‐held contrast‐enhanced magnetic resonance angiography (CE‐MRA) was first performed during the first pass of ferumoxytol injection, followed by the original MUSIC and the proposed CS‐PI MUSIC during the steady‐state distribution phase of ferumoxytol. Qualities of acquired images were then evaluated using a four‐point scale. Left ventricular volumes and ejection fractions calculated from the original MUSIC and the CS‐PI MUSIC were also compared with conventional multi‐slice 2D cardiac cine MRI. The proposed CS‐PI MUSIC reduced the imaging time of the MUSIC acquisition to 4.6 ± 0.4 min from 8.9 ± 1.2 min. Computationally intensive image reconstruction was completed within 5 min without interruption of sequential clinical scans. The proposed method (mean 3.3–4.0) provided image quality comparable to that of the original MUSIC (3.2–4.0) (all P ≥ 0.42), and better than conventional breath‐held first‐pass CE‐MRA (1.1–3.3) for 13 anatomical structures (all P ≤ 0.0014) with good inter‐observer agreement (κ > 0.46). The calculated ventricular volumes and ejection fractions from both original MUSIC (r > 0.90) and CS‐PI MUSIC (r > 0.85) correlated well with 2D cine imaging. In conclusion, PI and CS were successfully incorporated into the 4D MUSIC acquisition to further reduce scan time by approximately 50% while maintaining highly comparable image quality in a clinically practical reconstruction time. 相似文献
996.
The combination of chemotherapy and photodynamic therapy provides a promising approach for enhanced tumor eradication by overcoming the limitations of each individual therapeutic modality. However, tumor is pathologically featured with extreme hypoxia together with the adaptable overexpression of anti-oxidants, such as glutathione (GSH), which greatly restricts the therapeutic efficiency. Here, a combinatorial strategy was designed to simultaneously relieve tumor hypoxia by self-oxygenation and reduce intracellular GSH level to sensitize chemo-photodynamic therapy. In our system, a novel multi-functional nanosystem based on MnO2-doped graphene oxide (GO) was developed to co-load cisplatin (CisPt) and a photosensitizer (Ce6). With MnO2 doping, the nanosystem was equipped with intelligent functionalities: (1) catalyzes the decomposition of H2O2 into oxygen to relieve the tumor hypoxia; (2) depletes GSH level in tumor cells, and (3) concomitantly generates Mn2+ to proceed Fenton-like reaction, all of which contribute to the enhanced anti-tumor efficacy. Meanwhile, the surface hyaluronic acid (HA) modification could facilitate the targeted delivery of the nanosystem into tumor cells, thereby resulting in amplified cellular toxicity, as well as tumor growth inhibition in nude mice model. This work sheds a new light on the development of intelligent nanosystems for synergistic combination therapy via regulating tumor microenvironment.KEY WORDS: Cisplatin, Nanoparticles, Photosensitizer, Tumor microenvironment, Oxygenation, GSH depletion, Nanozyme, Targeting 相似文献
997.
由于医疗器械软件的特殊性,在产品注册后变更相对频繁,但现在对于医疗器械软件变更的监管要求尚未能充分考虑这种情况,应进一步科学合理设置相应监管要求。本文针对业内人士所关注焦点,分析了医疗器械软件变更类型划分原则,并基于相关变更类型划分,探讨了医疗器械软件变更的监管要求,最后提出了相关工作建议。 相似文献
998.
Ping Liu Xi-Ze Jia Yi Chen Yang Yu Kan Zhang Ya-Jie Lin Bao-Hong Wang Guo-Ping Peng 《CNS Neuroscience & Therapeutics》2021,27(2):163-173
AimsTo explore the potential relationships among gut microbiota (GM), local brain spontaneous activity, and neuropsychological characteristics in amnestic mild cognitive impairment (aMCI) patients.MethodsTwenty aMCI and 22 healthy control (HC) subjects were recruited. The GM composition was determined by 16S ribosomal RNA gene sequencing. Resting‐state functional magnetic resonance imaging scans were performed, and fractional amplitude of low‐frequency fluctuations (fALFF) was calculated across different frequencies. The Spearman or Pearson correlation analysis was used to analyze the relationship between spontaneous brain activity and cognitive function, and GM composition.ResultsaMCI patients had altered GM state and local spontaneous brain activity as compared with HC subjects. Correlation analysis showed that aMCI and HC groups had different “GM‐intrinsic brain activity interaction” patterns. In aMCI group, at the typical band (0.01‐0.08 Hz), the relative abundance (RA) of Bacteroides from phylum to genus level was negatively correlated with fALFF value of cerebellar vermis IV‐V, and the Ruminococcaceae RA was negatively correlated with fALFF values of left lenticular nucleus and pallidum. The Clostridiaceae RA and Blautia RA were positively correlated with the left cerebellum lobules IV‐V at the slow‐4 band (0.027‐0.073 Hz). The Veillonellaceae RA was positively correlated with fALFF values of left precentral gyrus at the slow‐5 band (0.073‐0.08 Hz). Correlation analysis showed that Clostridium members (Lachnospiraceae and Blautia) were positively, while Veillonellaceae was negatively, correlated with cognition test. Bacteroides was positively correlated with attention and computation, and negatively correlated with the three‐stage command score.ConclusionsaMCI patients have a specific GM‐intrinsic brain activity‐cognitive function interaction pattern. 相似文献
999.
非瓣膜性心房颤动(房颤)所致的脑栓塞是缺血性卒中最为常见的类型之一,且短期内栓塞复发风险较高,病情容易进展,尤其是抗凝药物应用不当时。复发性栓塞多以脑栓塞为主,肠系膜上动脉栓塞(superior mesenteric artery embolism,SMAE)少见。SMAE是严重的急腹症,病情凶险,当其进展为严重的缺血坏死性肠病并发罕见的肝门静脉积气(hepatic portal vein gas,HPVG)时往往预后极差,病死率很高。以往SMAE的影像诊断主要依靠腹部增强CT显示肠系膜上动脉充盈缺损来诊断,但对于碘对比剂禁忌者,非对比增强CT上出现的肠系膜上动脉内的“动脉致密征”也是一个有重要价值的诊断征象,以往罕见报道。现本文结合文献,报道1例经非对比剂增强腹部CT确诊的非瓣膜性房颤性卒中患者短期内并发急性SMAE并继发HPVG的罕见致死性案例。 相似文献
1000.
Adekunle Dawodu Barbara Davidson Jessica G. Woo Yong-Mei Peng Guillermo M. Ruiz-Palacios Maria de Lourdes Guerrero Ardythe L. Morrow 《Nutrients》2015,7(2):1081-1093
Although vitamin D (vD) deficiency is common in breastfed infants and their mothers during pregnancy and lactation, a standardized global comparison is lacking. We studied the prevalence and risk factors for vD deficiency using a standardized protocol in a cohort of breastfeeding mother-infant pairs, enrolled in the Global Exploration of Human Milk Study, designed to examine longitudinally the effect of environment, diet and culture. Mothers planned to provide breast milk for at least three months post-partum and were enrolled at four weeks postpartum in Shanghai, China (n = 112), Cincinnati, Ohio (n = 119), and Mexico City, Mexico (n = 113). Maternal serum 25(OH)D was measured by radioimmunoassay (<50 nmol/L was categorized as deficient). Serum 25(OH)D was measured in a subset of infants (35 Shanghai, 47 Cincinnati and 45 Mexico City) seen at 26 weeks of age during fall and winter seasons. Data collected prospectively included vD supplementation, season and sun index (sun exposure × body surface area exposed while outdoors). Differences and factors associated with vD deficiency were evaluated using appropriate statistical analysis. vD deficiency in order of magnitude was identified in 62%, 52% and 17% of Mexican, Shanghai and Cincinnati mothers, respectively (p < 0.001). In regression analysis, vD supplementation (p < 0.01), obesity (p = 0.03), season (p = 0.001) and sites (p < 0.001) predicted maternal vD status. vD deficiency in order of magnitude was found in 62%, 28%, and 6% of Mexican, Cincinnati and Shanghai infants, respectively (p < 0.001). Season (p = 0.022), adding formula feeding (p < 0.001) and a higher sun index (p = 0.085) predicted higher infant vD status. vD deficiency appears to be a global problem in mothers and infants, though the prevalence in diverse populations may depend upon sun exposure behaviors and vD supplementation. Greater attention to maternal and infant vD status starting during pregnancy is warranted worldwide. 相似文献