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21.
从质量守恒定律出发,以Buswell提出的垃圾好氧降解反应方程式为基础,建立了计算通风量的化学计量模型;以达西定律为基础,建立了计算通风压力的数学模型;并将其应用于某封场垃圾填埋场原位好氧治理工程的计算,验证了2个模型的合理性和准确性,可为生活垃圾填埋场好氧生物反应器工艺设计和设备选型提供理论数据参考。  相似文献   
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Abstract

Background and aim: Capsule retention is the most common adverse event associated with video capsule endoscopy. The use of double-balloon enteroscopy-assisted capsule endoscope retrieval has been increasingly reported in recent years. However, evidence is limited regarding its success rate, associated factors, and subsequent clinical outcomes.

Methods: A systematic review of relevant studies published before January 2019 was performed. Successful retrieval rate and associated factors, rate of endoscopic balloon dilation, and outcomes after double-balloon enteroscopy were summarized and pooled.

Results: Within 154 associated original articles, 12 including 150 cases of capsule retrieval by double-balloon enteroscopy were included. The estimated pooled successful retrieval rate was 86.5% (95% confidence interval, 75.6–95.1%). Anterograde approach and capsules retained in the jejunum or trapped by malignant strictures were associated with a higher successful retrieval rate than the retrograde approach (62/83 [74.7%] vs. 10/38 [26.3%], p?<?.001) and capsules retained in the ileum (41/41 [100.0%] vs. 43/58 [74.1%], p?<?.001) or trapped by benign strictures (21/21 [100.0%] vs. 65/83 [78.3%], p?=?.043). Endoscopic balloon dilation was performed in 38.8% (95% confidence interval, 22.3–56.3%) of patients with benign strictures. Two perforations (1.3%) were reported as severe adverse events after double-balloon enteroscopy. A significantly lower surgery rate was found among cases with successful video capsule removal compared with unsuccessful cases (7.2% vs. 38.5%, p?=?.002).

Conclusions: Double-balloon enteroscopy is feasible and safe for removing retained video capsule endoscopes, and its use could decrease the need for surgery in patients with benign strictures and facilitate subsequent surgery in patients with malignant strictures.  相似文献   
24.
目的 分析tCGA数据库中肝内胆管癌(ICC)高通量测序数据,寻找其预后相关基因,构建风险模型,并研究其在ICC组织中表达及作用通路。方法 下载tCGA数据库中33例ICC组织和8例癌旁组织中的RNA-seq表达矩阵数据和患者临床资料信息,利用edgeR软件包进行基因差异表达分析,通过单因素Cox回归分析筛选出预后相关差异基因,对差异基因绘制生存曲线,筛选出具有临床意义的基因,经多因素Cox回归分析并构建风险模型,通过京都基因与基因组百科全书(KEGG)通路富集分析了解预后相关基因的作用通路。结果 通过edgeR分析后得到6 617个差异基因(筛选标准为|log2 Fold Change|>1,P<0.05),其中高表达组4 094个,低表达组2 523个。通过功能富集发现,这些基因主要集中在化学物致癌作用、药物代谢-细胞色素P450系统、细胞色素P450对异生物质的代谢影响以及视黄醇代谢通路。经单因素Cox回归、R软件“survival”包生存曲线分析显示,UCN2、CST1、PROS1、SLC35E4、PEMT五个基因对ICC患者预后存在显著性影响。通过多因素Cox回归分析,CST1、PEMT、PROS1构建的风险模型对ICC患者预后具有判断作用。结论 UCN2、CST1、PROS1、SLC35E4、PEMT基因可能成为ICC预后判断指标,为后续临床试验提供数据支持。  相似文献   
25.
ObjectivesEarly diagnosis of cognitive impairment is increasingly emphasized in the literature to facilitate timely preventive interventions. Although bedside cognitive tests such as the Montreal Cognitive Assessment (MoCA) are widely used for such early diagnostic purposes, they may not have comparable performance to a full neuropsychological battery (FNB) in diagnosing early cognitive impairment. This study investigated whether a small subset of neuropsychological tests can be added on to MoCA to match its performance to that of the FNB in discriminating mild cognitive impairment and dementia (MCI/dementia) from normal cognition.DesignCross-sectional diagnostic study.SettingAlzheimer's Disease Centers across the United States.ParticipantsOlder participants (≥50 years) who completed MoCA and the FNB (N = 9187).MeasuresThe study sample was split into two: the derivation sample (n = 1837) was used to develop a brief neuropsychological battery that best discriminated MCI/dementia (using the best-subset approach with 10-fold cross-validation); while the validation sample (n = 7350) verified its actual performance in discriminating MCI/dementia.ResultsA 3-item neuropsychological battery was identified, comprising MoCA, Benson Complex Figure Recall, and Craft Story 21 Delayed Recall. It had excellent performance in discriminating MCI/dementia from normal cognition (area under the receiver operating characteristic curve [AUROC] 90.0%, 95% confidence interval [CI] 89.2%-90.7%), which was comparable to that of the FNB (AUROC 88.4%, 95% CI 87.6%-89.2%). By contrast, MoCA alone had significantly worse AUROC (86.9%, 95% CI 86.0%-87.7%) than that of the FNB.Conclusions/ImplicationsUsing rigorous methods, this study developed a brief neuropsychological battery that maintained the brevity of a bedside cognitive test, while rivaling the diagnostic performance of an FNB in early cognitive impairment. This brief battery offers a viable alternative when the FNB is needed but cannot be feasibly administered in nonspecialty clinics. It can have a wider health systems effect of improving patients’ access to accurate diagnosis in early cognitive impairment and facilitating timely interventions to delay the progression of cognitive impairment.  相似文献   
26.
BACKGROUND: The validity of parent reports regarding children's attention-deficit/hyperactivity disorder (ADHD) symptoms has been questioned. This study assessed whether parent reports were as sensitive as teacher reports to document change in ADHD symptoms during clinical trials with atomoxetine. METHODS: Data were compared from two randomized, double-blind, placebo-controlled clinical trials of atomoxetine using different versions (parent or teacher) of the same rating scale (Attention-Deficit/Hyperactivity Disorder Rating Scale-IV [parent or teacher] Version: Investigator Administered and Scored - ADHD RS). Exclusion criteria included history of bipolar disorder, psychosis, seizures, alcohol abuse, or positive drug screen. Patients (6-16 years old) were treated with atomoxetine (titrated to a maximum dose of 1.8 mg/kg/day) administered once daily for up to 7 weeks. Parent and teacher ratings were compared using an analysis of covariance (ANCOVA) model. RESULTS: The analysis (n = 318) showed that treatment effects (mean change, baseline to endpoint) were similar between parent and teacher ratings (total, p = .762; inattention, p = .519; hyperactive/impulsive, p = .955). Effect sizes also were similar based on total scores (parent ratings = .69; teacher ratings = .63). CONCLUSIONS: Parent reports are as sensitive as teacher reports in assessing the efficacy of long-acting pharmacologic treatment for ADHD in children during clinical trials using the nonstimulant atomoxetine.  相似文献   
27.
目的评估增强减影在脊椎转移瘤MR I中的应用价值。方法50例脊椎转移瘤病人进行MR I增强扫描,对比剂采用Gd-DTPA(0.1 mmol/kg),然后用T1W I增强后的图像与增强前的图像进行减影。通过对比噪声比(CNR)、信噪比(SNR)以及肿瘤边界清晰程度的比较,对MR I减影与否进行评估。结果MR I对比增强减影图像比传统的T1W I增强图像显示更清晰、更直观。所有脊椎转移瘤图像MR I减影的CNR和SNR比常规T1W I增强图像的CNR和SNR高。MR I减影CNR为155.05±24.73(x±SD),常规T1W I增强图像的CNR为11.11±14.26(t=35.65,Ρ<0.001)。MR I减影SNR为192.82±32.89(x±SD),常规T1W I增强图像的SNR为46.03±28.22(t=23.95,Ρ<0.001))。MR I对比增强减影图像比传统的T1W I增强图像能更好地显示脊椎转移瘤的边界和侵犯情况(2χ=29.34,Ρ<0.005)。结论MR I增强减影为探查和评估脊椎转移瘤提供了一个新的诊断方法。  相似文献   
28.
目的了解我院门诊就诊者对子宫颈病变相关知识的认识。方法自制问卷调查表,采用无记名,当面问卷调查方式。结果从调查100例就诊者中,未做过健康体检、妇科盆腔检查和宫颈刮片检查分别为34例、24例和52例。对宫颈癌的认识不知道者53例。结论建议相关部门加强对妇女的健康教育,提高其健康意识,强化临床医生的防癌意识和对子宫病变的规范化诊治。  相似文献   
29.
We report clinical, neuroradiologic features, and neuropathologic findings of a 76‐year‐old man with coexistent Pick’s disease and progressive supranuclear palsy. The patient presented with loss of recent memory, abnormal behavior and change in personality at the age of 60. The symptoms were progressive. Three years later, repetitive or compulsive behavior became prominent. About 9 years after onset, he had difficulty moving and became bed‐ridden because of a fracture of his left leg. His condition gradually deteriorated and he developed mutism and became vegetative. The patient died from pneumonia 16 years after the onset of symptoms. Serial MRI scans showed progressive cortex atrophy, especially in the bilateral frontal and temporal lobes. Macroscopic inspection showed severe atrophy of the whole brain, including cerebrum, brainstem and cerebellum. Microscopic observations showed extensive superficial spongiosis and severe neuronal loss with gliosis in the second and third cortical layers in the frontal, temporal and parietal cortex. There were Pick cells and argyrophilic Pick bodies, which were tau‐ and ubiquitin‐positive in neurons of layers II–III of the above‐mentioned cortex. Numerous argyrophilic Pick bodies were observed in the hippocampus, especially in the dentate fascia. In addition, moderate to severe loss of neurons was found with gliosis and a lot of Gallyas/tau‐positive globus neurofibrillary tangles in the caudate nucleus, globus pallidus, thalamus, substantia nigra, locus coeruleus and dentate nucleus. Numerous thorned‐astrocytes and coiled bodies but no‐tuft shaped astrocytes were noted in the basal ganglion, brainstem and cerebellar white matter. In conclusion, these histopathological features were compatible with classical Pick’s disease and coexistence with progressive supranuclear palsy without tuft‐shaped astrocytes.  相似文献   
30.
医学插图的艺术创作   总被引:1,自引:1,他引:0  
介绍了医学插图艺术创作的方法:即在依据医学科学内容的基础上,遵循美学规律,运用科学的艺术表现形式,准确、形象、生动地表达出医学科学的深刻内涵,从而实现医学科学与艺术完美结合的创作目标。  相似文献   
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