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51.
目的上皮-间充质化(epithelial-mesenchymal transition,EMT)是实体瘤原发灶癌细胞获得转移能力的基础。缺氧诱导前列腺癌、肾癌、卵巢癌的EMT过程已得到证实,缺氧诱导因子1α(hypoxia inducible factor 1 alpha,HIF-1α)在这些过程中发挥重要作用。但是HIF-1α和肝癌细胞EMT之间的关系目前并不清楚。本文探讨HIF-1α在肝癌EMT中的作用。方法利用可调控HIF-1α表达的肝癌HepG2Tet-on-HIF-1α细胞系,在排除缺氧其他反应干扰的情况下研究HIF-1α在肝癌细胞EMT过程中的作用和机制。结果过表达HIF-1α促进HepG2肝癌细胞EMT,下调HIF-1α表达可以抑制HepG2肝癌细胞EMT。HIF-1α促进EMT相关转录因子Snail的表达。结论 HIF-1α通过上调Snail来促进HepG2肝癌细胞EMT。  相似文献   
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53.
类消胶囊治疗类风湿关节炎的临床观察与实验研究   总被引:8,自引:0,他引:8  
金忠棋  陈健  林洁  周游 《中国骨伤》2000,13(7):404-405
目的 研究类消胶囊对类曲湿性关节炎的治疗作用。方法 对30例类风湿关节炎患者服用类消胶囊的后进行血清NPT-2R水平测定。300你储血员作为对照组,测得NPT≤100mg/ml、H、2R≤250u/ml。结果 服前药NPT与IL-2R水平明显高于对照组(P〈0.001)。服药后NPT与IL-2R测定其平均值明显低于有取药前(P〈0.001)。结论 类消胶囊可降低NPT和IL-2R,而NPT和IL-  相似文献   
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55.
Background and aimThe aim of this study is to evaluate whether the long-term (≥4 weeks) use of proton pump inhibitors (PPIs) is a risk factor for intubation requirement and mortality in patients hospitalized for COVID-19.Materials and methods In this multicentric retrospective study, a total of 382 adult patients (≥18 years of age) with confirmed COVID-19 who were hospitalized for treatment were enrolled. The patients were divided into two groups according to the periods during which they used PPIs: the first group included patients who were not on PPI treatment, and the second group included those who have used PPIs for more than 4 weeksResultsThe study participants were grouped according to their PPI usage history over the last 6 months. In total, 291 patients did not use any type of PPI over the last 6 months, and 91 patients used PPIs for more than 4 weeks. Older age (HR: 1.047, 95% CI: 1.026–1.068), current smoking (HR: 2.590, 95% CI: 1.334–5.025), and PPI therapy for more than 4 weeks (HR: 1.83, 95% CI: 1.06–2.41) were found to be independent risk factors for mortalityConclusionThe results obtained in this study show that using PPIs for more than 4 weeks is associated with negative outcomes for patients with COVID-19. Patients receiving PPI therapy should be evaluated more carefully if they are hospitalized for COVID-19 treatment.  相似文献   
56.
目的:采用正交试验方法,研究超滤工艺对风痛宁注射液有效成分的影响。方法:以温度、pH值、药液浓度和超滤膜截留分子量4因素进行正交设计,盐酸青藤碱为检测指标,测定超滤前后药液成分浓度,通过计算透过率来观察盐酸青藤碱超滤前后的含量变化。结果:温度、pH值、药液浓度和超滤膜截留分子量4个考察因素对盐酸青藤碱透过率无显著影响。结论:风痛宁注射液有效成分进行超滤的适用性较好。  相似文献   
57.
Background/aimThis study aims to evaluate of olfactory and gustatory functions of COVID-19 patients and possible risk factors for olfactory and gustatory dysfunctions. Materials and methodsThe cross-sectional study included adult patients who were diagnosed with COVID-19 in Gazi University Hospital between April 2020 and June 2020. Volunteered patients participated in a survey in which olfactory and gustatory functions and various clinical information were questioned. Sinonasal Outcome Test-22 was also administrated to all patients.ResultsA hundred and seventy-one patients participated in this study. Olfactory and gustatory dysfunctions rates were 10.5% (n: 18) and 10.5% (n: 18), respectively. Patients without any symptom other than smell and taste dysfunctions were clustered as group 1 and patients who are clinically symptomatic were clustered as group 2. Olfactory dysfunction occurred in 8% of group 1 and 17.4% of group 2 (p = 0.072). Gustatory dysfunction rate of smokers was 19.7% and significantly higher than gustatory dysfunction rate of nonsmokers (5.5%) (p = 0.007). Twenty-seven-point-eight percent of the patients with olfactory dysfunction (n = 5) were male and 72.2% (n: 13) were female. Sex did not show significant effect on rate of olfactory dysfunction. Twenty-five patients participated in psychophysical olfactory function test. No participant reported olfactory dysfunction at the time of test. Of the participants, 64% (n: 16) were normosmic and 36% (n: 9) were hyposmic according to Sniffin’ Stick test. ConclusionOlfactory and gustatory dysfunctions are more common in patients who are clinically symptomatic than those diagnosed during contact tracing. Objective tests may show that frequency of olfactory dysfunction is greater than frequency of self-reported olfactory dysfunction.  相似文献   
58.
测试磁驱动轴流心室辅助装置主体血泵溶血性能。利用计算流体力学(CFD)软件ANSYS,基于红细胞受到切应力和相应曝光时间的计算溶血方法预测血泵溶血性能,计算红细胞粒子随着时间推移在血泵内运动轨迹上受到破坏程度。通过体外模拟循环实验实际测试血泵体外溶血性能,计算得到血泵实际标准溶血指数。CFD计算结果转化的标准溶血指数与实际体外实验结果比较相差较大,与CFD计算简化和实际计算循环周期有很大关系。磁驱动轴流心室辅助装置主体血泵有较好的实际溶血性能,血泵实验期间无不良状况发生,可以进行进一步实验。  相似文献   
59.
The aim of this study is to examine relationships of sleep duration with sociodemographic and health‐related factors, psychiatric disorders and sleep disturbances in a nationwide sample in Korea. A total of 6510 subjects aged 18–64 years participated in this study. Logistic regression was used to calculate the odd ratios and 95% confidence intervals of the covariates, psychiatric disorders and sleep disturbances across the following sleep duration categories: 5 h or less, 6, 7, 8 and 9 h or more per day. Low levels of education, unemployment and physical illness were associated with sleeping for 5 h or less and 9 h or more. Being older and widowed/divorced/separated, high levels of physical activity, pain/discomfort, obesity and high scores on the General Health Questionnaires were associated with sleeping for 5 h or less. Female, being younger and underweight were associated with sleeping for 9 h or more. Alcohol dependence, anxiety disorder and social phobia were associated significantly with sleeping for 5 h or less and 9 h or more. Other psychiatric disorders were more common in subjects who slept for 5 h or less (e.g. alcohol use disorder, mood disorder, major depressive disorder, dysthymic disorder, obsessive‐compulsive disorder and specific phobia) or 9 h or more (e.g. post‐traumatic stress disorder). In addition, subjects who slept for 5 h or less reported more sleep disturbances than did subjects who slept for 7 h. Short or long sleep is associated with psychiatric disorders and/or sleep disturbance, therefore attention to the mental health of short or long sleepers is needed.  相似文献   
60.
ENAMEL MATRIX DERIVATIVE (EMDOGAIN®) FOR PERIODONTAL TISSUE REGENERATION IN INTRABONY DEFECTS (Cochrane Review). In: THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS, ISSUE 4, 2005.Esposito M, Grusovin MG, Coulthard P, Worthington H

Background

Periodontitis is a chronic infective disease of the gums caused by bacteria present in dental plaque. This condition induces the breakdown of the tooth-supporting apparatus until teeth are lost. Surgery may be indicated to arrest disease progression and regenerate lost tissues. Several surgical techniques have been developed to regenerate periodontal tissues including guided tissue regeneration (GTR), bone grafting (BG), and the use of enamel matrix derivative (EMD). EMD is an extract of enamel matrix and contains amelogenins of various molecular weights. Amelogenins are involved in the formation of enamel and periodontal attachment formation during tooth development.

Objectives

The objectives were to test whether EMD is effective, and to compare EMD versus GTR and various BG procedures for the treatment of intrabony defects.

Search strategy

We searched the Cochrane OHG Trials Register, Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE. Several journals were hand searched. No language restrictions were applied. Authors of randomized controlled clinical trials (RCTs) who were identified, personal contacts, and the manufacturer were contacted to identify unpublished trials. The most recent search was May 2005.

Selection criteria

Selected studies were RCTs on patients affected by periodontitis having intrabony defects of at least 3 mm treated with EMD compared with open flap debridement, GTR, and various BG procedures with at least 1 year of follow-up. The outcome measures considered were tooth loss, changes in probing attachment levels (PAL), pocket depths (PPD), gingival recessions (REC), bone levels from the bottom of the defects on intraoral radiographs, esthetics, and adverse events. The following time points were to be evaluated: 1, 5, and 10 years.

Data collection & analysis

Screening of eligible studies, assessment of the methodological quality of the trials, and data extraction were conducted in duplicate and independently by 2 authors. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios (RR) for dichotomous outcomes with 95% confidence intervals (CI). It was decided not to investigate heterogeneity, but a sensitivity analysis for the risk of bias of the trials was performed.

Main results

Ten trials were included out of 29 potentially eligible trials. No included trial presented data after 5 years of follow-up, therefore all data refer to the 1-year time point. A meta-analysis including 8 trials showed that EMD-treated sites displayed statistically significant PAL improvements (mean difference 1.2 mm, 95% CI 0.7 to 1.7) and PPD reduction (0.8 mm, 95% CI 0.5 to 1.0) when compared to placebo or control treated sites, although a high degree of heterogeneity was found. Significantly more sites had less than 2 mm PAL gain in the control group, with RR 0.48 (95% CI 0.29 to 0.80). Approximately 6 patients needed to be treated (NNT) to have 1 patient gaining 2 mm or more PAL over the control group, based on a prevalence in the control group of 35%. No differences in tooth loss or esthetic appearance as judged by the patients were observed. When evaluating the only 2 trials at a low risk of bias in a sensitivity analysis, the effect size for PAL was 0.6 mm, which was less than 1.2 mm for the overall result. Comparing EMD with GTR (5 trials), GTR showed a statistically significant increase of REC (0.4 mm) and significantly more postoperative complications. No trials were found comparing EMD with BG.

Reviewers' conclusions

One year after its application, EMD significantly improved PAL levels (1.2 mm) and PPD reduction (0.8 mm) when compared to a placebo or control, however, the high degree of heterogeneity observed among trials suggests that results have to be interpreted with great caution. In addition, a sensitivity analysis indicated that the overall treatment effect might be overestimated. The actual clinical advantages of using EMD are unknown. With the exception of significantly more postoperative complications in the GTR group, there was no evidence of clinically important differences between GTR and EMD.

Abstract

INTERVENTIONS FOR REPLACING MISSING TEETH: DENTAL IMPLANTS IN ZYGOMATIC BONE FOR THE REHABILITATION OF THE SEVERELY DEFICIENT EDENTULOUS MAXILLA (Cochrane Review). In: THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS, ISSUE 4, 2005.Esposito M, Worthington HV, Coulthard P

Background

Dental implants are used for replacing missing teeth. Placing dental implants is limited by the presence of adequate bone volume permitting their anchorage. Several bone-augmentation procedures have been developed to solve this problem. Zygomatic implants are long screw-shaped implants developed as a partial or complete alternative to bone augmentation procedures for the severely atrophic maxilla. One to 3 zygomatic implants can be inserted through the posterior alveolar crest and maxillary sinus to engage the body of the zygomatic bone. A couple of conventional dental implants are also needed in the frontal region of the maxilla to stabilize the prosthesis. The potential main advantages of zygomatic implants could be that in some situations bone grafting may not be needed and a fixed denture could be fitted sooner. Another specific indication for using zygomatic implants could be the need for maxillary reconstruction after maxillectomy in cancer patients.

Objectives

The objective was to test the hypothesis of no difference in outcomes between zygomatic implants with and without bone-augmenting procedures in comparison with conventional dental implants in augmented bone for severely resorbed maxillae.

Search strategy

We searched the Cochrane Oral Health Group's Trial Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and EMBASE. We hand searched several dental journals. No language restrictions were applied. Personal contacts and all known zygomatic implant manufacturers were contacted to identify unpublished trials. The most recent search was May 2005.

Selection criteria

Studies selected were randomized controlled clinical trials (RCTs) that included patients with severely resorbed maxillae who could not be rehabilitated with conventional dental implants and were treated with zygomatic implants with and without bone grafts versus patients treated with conventional dental implants in conjunction with bone-augmentation procedures having a follow-up of at least 1 year. Outcome measures considered were prosthesis and implant failures, side effects, patient satisfaction, and cost-effectiveness.

Data collection & analysis

Screening of eligible studies, assessment of the methodological quality of trials, and data extraction were to be conducted in duplicate and independently by 2 authors. Results were to be expressed as random-effects models using weighted mean differences for continuous outcomes and risk ratio for dichotomous outcomes with 95% confidence intervals. Heterogeneity was to be investigated including both clinical and methodological factors.

Main results

No RCTs or controlled clinical trials (CCTs) were identified.

Reviewers' conclusions

There is the need for RCTs in this area to assess whether zygomatic implants offer some advantages over alternative bone-augmentation techniques for treating atrophic maxillae.  相似文献   
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