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71.
目的 研究基于多学科(M D)合作在创建下肢慢性溃疡伤口规范化治疗的应用价值.方法 选取2018年10月至2019年9月在复旦大学附属华山医院收治的下肢慢性溃疡患者536例为研究对象,随机分为试验组(n=270)和对照组(n=266),对照组予以单一科室治疗管理模式,试验组采用MD合作管理模式,对两组患者干预前和干预后...  相似文献   
72.
Objective:Hepatocyte nuclear factor 4α (HNF4A) has been demonstrated to be an oncogene in gastric cancer (GC). However, the roles of different HNF4A isoforms derived from the 2 different promoters (P1 and P2) and the underlying mechanisms remain obscure.Methods:The expression and prognostic values of P1- and P2-HNF4A were evaluated in The Cancer Genome Atlas (TCGA) databases and GC tissues. Then, functional assays of P1- and P2-HNF4A were conducted both in vivo and in vitro. High-throughput RNA-seq was employed to profile downstream pathways in P1- and P2-HNF4A-overexpressing GC cells. The expression and gene regulation network of the candidate target genes identified by RNA-seq were characterized based on data mining and functional assays.Results:HNF4A amplification was a key characteristic of GC in TCGA databases, especially for the intestinal type and early stage. Moreover, P1-HNF4A expression was significantly higher in tumor tissues than in adjacent non-tumor tissues (P < 0.05), but no significant differences were found in P2-HNF4A expression (P > 0.05). High P1-HNF4A expression indicated poor prognoses in GC patients (P < 0.01). Furthermore, P1-HNF4A overexpression significantly promoted SGC7901 and BGC823 cell proliferation, invasion and migration in vitro (P < 0.01). Murine xenograft experiments showed that P1-HNF4A overexpression promoted tumor growth (P < 0.05). Mechanistically, RNA-seq showed that the cytokine-cytokine receptor interactions pathway was mostly enriched in P1-HNF4A-overexpressing GC cells. Finally, chemokine (C-C motif) ligand 15 was identified as a direct target of P1-HNF4A in GC tissues.Conclusions:P1-HNF4A was the main oncogene during GC progression. The cytokine-cytokine receptor interaction pathway played a pivotal role and may be a promising therapeutic target.  相似文献   
73.
Constipation is a common problem in sows and women during late pregnancy. Dietary fiber has potential in the regulation of intestinal microbiota, thereby promoting intestinal motility and reducing constipation. However, the effects of fibers with different physicochemical properties on intestinal microbe and constipation during late pregnancy have not been fully explored. In this study, a total of 80 sows were randomly allocated to control and one of three dietary fiber treatments from day 85 of gestation to delivery: LIG (lignocellulose), PRS (resistant starch), and KON (konjaku flour). Results showed that the defecation frequency and fecal consistency scores were highest in PRS. PRS and KON significantly increased the level of gut motility regulatory factors, 5-hydroxytryptamine (5-HT), motilin (MTL), and acetylcholinesterase (AChE) in serum. Moreover, PRS and KON promoted the IL-10 level and reduced the TNF-α level in serum. Furthermore, maternal PRS and KON supplementation significantly reduced the number of stillborn piglets. Microbial sequencing analysis showed that PRS and KON increased short-chain fatty acids (SCFAs)-producing genera Bacteroides and Parabacteroides and decreased the abundance of endotoxin-producing bacteria Desulfovibrio and Oscillibacter in feces. Moreover, the relative abundance of Turicibacter and the fecal butyrate concentration in PRS were the highest. Correlation analysis further revealed that the defecation frequency and serum 5-HT were positively correlated with Turicibacter and butyrate. In conclusion, PRS is the best fiber source for promoting gut motility, which was associated with increased levels of 5-HT under specific bacteria Turicibacter and butyrate stimulation, thereby relieving constipation. Our findings provide a reference for dietary fiber selection to improve intestinal motility in late pregnant mothers.  相似文献   
74.
This paper focuses on the effect of gear steel on distortion due to phase transformation in carburizing and quenching. The carburizing and quenching process of C-rings under suspension was studied by using the finite element method based on the thermo-mechanical theory, considering phase transformation. The phase transformation kinetics parameters, depending on different carbon contents, were measured by Gleeble-3500. The distortion behavior of the carburized C-ring during the cooling stage was analyzed, as well as the carbon concentration distribution and martensite volume fractions. The accuracy of the simulation was also verified by comparing the experimental data with the simulated result of the distortion and microstructure. A reliable basis is provided for predicting the distortion mechanism of gear steels in carburizing and quenching.  相似文献   
75.
ObjectiveWe sought to examine the current skin quality trends and gaps in clinical practice in the Asia Pacific region and develop a practical guide to improve skin quality.MethodsMedical practitioners from 11 countries in the Asia Pacific region completed an online survey on current trends in skin quality treatment. A panel of 12 leading experts convened for a virtual meeting to develop a practical guide for skin quality improvement.ResultsA total of 153 practitioners completed the survey. The four most common skin quality issues were uneven skin tone, skin surface unevenness, skin laxity, and sebaceous gland hyperactivity and enlarged pores. Most practitioners reported using a combination of treatment modalities for each skin quality issue. It was also observed that each treatment modality could be used to treat several skin quality issues. A multimodal approach targeting different interrelated issues across the tissue planes was recommended for balanced results. The panel developed a practical guide for the appropriate combinations and sequence of treatments, and created treatment protocols for specific skin quality outcome goals. The guide employed an “inside-out” approach, treating the deeper tissue planes prior to the superficial layers to achieve harmonious results.LimitationsFuture studies are needed to support the recommended treatment protocols for skin quality improvement.ConclusionThese findings provide valuable insights on current skin quality trends and gaps in clinical practice. The practical guide provides a framework for practitioners to customize their treatment plan according to each patient’s needs.  相似文献   
76.
In this paper, highly flame retardant C60/PMMA composites were prepared using an in situ polymerization method by introducing fullerene (C60) into polymethyl methacrylate (PMMA) to improve its combustion characteristics. The apparent morphologies of PMMA and C60/PMMA microspheres were observed by scanning electron microscopy (SEM), and the structure was characterized by infrared spectroscopy (FT-IR). The thermal stability and flame retardancy were characterized using a synchronous thermal analyzer, a cone calorimeter and an oxygen index tester. The results show that the maximum initial decomposition temperature of C60/PMMA-2 (prepared using C60 with a concentration of 2 mg mL−1) is 234.89 °C, which is about 59.89 °C higher than that of PMMA, and the thermal stability is the best. The limiting oxygen index of the C60/PMMA-2 composite is 21.8, which is 28.2% higher than that of pure PMMA. In addition, the peak heat release rate (PHRR) of C60/PMMA is reduced by 630.4 kW m−2 when compared with pure PMMA, which means that the flame retardant property is improved. Meanwhile, the mechanical properties of the PMMA are also improved by adding C60.

In this paper, highly flame retardant C60/PMMA composites were prepared using an in situ polymerization method by introducing fullerene (C60) into polymethyl methacrylate (PMMA) to improve its combustion characteristics.  相似文献   
77.
BACKGROUNDLipid metabolism disorder and inflammatory-immune activation are vital triggers in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Various studies have shown that PPAR-γ exerts potent anti-inflammatory and immunomodulatory properties. However, little is known about the regulation of PPAR-γ activity in modulating cell crosstalk in NAFLD.AIMTo investigate whether the regulation of PPAR-γ activity in lipid-laden hepatocytes affects macrophage polarization and inflammation.METHODSPrimary hepatocytes were isolated from wild-type C57BL6/J mice or hepatocyte-specific PPAR-γ knockout mice and incubated with free fatty acids (FFAs). Macrophages were incubated with conditioned medium (CM) from lipid-laden hepatocytes with or without a PPAR-γ agonist. Wild-type C57BL/6J mice were fed a high-fat (HF) diet and administered rosiglitazone.RESULTSPrimary hepatocytes exhibited significant lipid deposition and increased ROS production after incubation with FFAs. CM from lipid-laden hepatocytes promoted macrophage polarization to the M1 type and activation of the TLR4/NF-κB pathway. A PPAR-γ agonist ameliorated oxidative stress and NLRP3 inflammasome activation in lipid-laden hepatocytes and subsequently prevented M1 macrophage polarization. Hepatocyte-specific PPAR-γ deficiency aggravated oxidative stress and NLRP3 inflammasome activation in lipid-laden hepatocytes, which further promoted M1 macrophage polarization. Rosiglitazone administration improved oxidative stress and NLRP3 inflammasome activation in HF diet-induced NAFLD mice in vivo.CONCLUSIONUpregulation of PPAR-γ activity in hepatocytes alleviated NAFLD by modulating the crosstalk between hepatocytes and macrophages via the reactive oxygen species-NLRP3-IL-1β pathway.  相似文献   
78.
耳蜗电图在梅尼埃病诊断中的价值   总被引:4,自引:0,他引:4  
迄今尚缺乏诊断梅尼埃病的敏感且特异的客观试验,70年代以来,若干研究探讨了耳蜗电图(Electrocochleogram,ECochG)在梅尼埃病诊断中的价值,认为典型的改变是-SP异常增大,导致-SP/AP比值增高,以及-SP-AP复合波形异常增宽。各家报告-SP/AP诊断梅尼埃病阳性率从32%至87%.本文报告了97例100耳梅尼埃病鼓室内法检测的耳蜗电图结果,49例-SP/AP比值异常增高,阳性率49%;波型异常增宽17耳,总阳性率66%.眼震电图检测的阳性率61%.耳蜗电图和眼震电图改变一致的43耳,二者总阳性率为84%。对各家阳性率不一致的原因作了分析。认为耳蜗电图-SP/AP比值诊断梅尼埃病的敏感性不如文献报告的那么乐观,在目前尚无更敏感更特异的诊断手段的情况下,耳蜗电图和眼震电图在梅尼埃病的诊断中起着相互印证和相互补充的作用。  相似文献   
79.
通过对600例血脂异常患者中医证侯的研究,总结了血脂异常中医证候分布的规律,确认血脂异常患者的病机是以本虚为主,脾虚和肾虚是血脂异常发病的主要病理基础,痰浊和瘀血也是影响血脂异常中医证候的重要因素,建议在治疗时应以补脾益肾为主要治疗原则。并首次在血脂异常的辨证中提出了"无证候可辨"的概念。通过对血脂异常中医证候与代谢综合征(MS)相关性的研究发现血脂异常中医证候的产生与MS及其组分中的超重或肥胖及高血压密切相关,提出MS及其各组分的存在是引起血脂异常中医虚证的重要因素,阐明了应用辨证论治的方法在治疗血脂异常的同时可以改善MS,还可以提高患者的生活质量,因而优于单纯的降脂治疗。  相似文献   
80.
We are describing a novel technique to insert nasogastric tube (NGT) in the anesthetized patients dur- ing cervical esophageal reconstruction. Methods: Forty patients with mid and upper esophageal tumor enrolled into this study were randomly allocated into two groups (the control group, group C and the novel method group, group N). All the patients were applied mechanical anastomosis to finish the cervical esophageal reconstruction. The procedure of NGT insertion for group C use the conventional method; well, the group N use the novel technique. Results: All the patients in group N had been finished the NGT insertion in the first attempt, and the total time for insertion was (5.05 + 1.15) mins; on the contrary, for the group C, duration of insertion (min) was (24.45 ± 5.23) mins, and the successful rate of NGT insertion in the first attempt was 40% (P〈 0.05); no one in group N had coiling/kinking, and 6/20 (30%) in group C had it (P= 0.020). The complication rate of bleeding between the two group had no significant difference. Conclusion: For the patient with mid and upper esophageal tumor who need cervical esophageal reconstruction, this novel method can save the NGT insertion time, and make it easier with higher successful rate.  相似文献   
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