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1.
[目的]探讨应用腔镜下超声刀食管癌切除术对患者术后疼痛介质释放及氧化应激反应的影响.[方法]回顾性分析本院收治的127例食管癌患者的临床资料,根据手术方法的不同将其分为观察组(腔镜下超声刀食管癌切除术,n=65)和对照组(腔镜下电刀食管癌切除术,n=62).比较两组术中情况及并发症发生率,同时比较手术前后两组血清五羟色胺(5-HT)、去甲肾上腺素(NE)及钾离子(K^+)水平,不同时刻超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、丙二醛(MDA)水平.[结果]观察组手术时间、术中出血、胸腔引流量均低于对照组,清扫淋巴结数量高于对照组,差异有统计学意义(P<0.05).术后两组血清5-HT、K^+、NE水平高于术前,观察组低于对照组,差异有统计学意义(P<0.05).术毕、术后3 h两组SOD、GSH-Px水平低于术前,MDA水平高于术前,且两组比较差异均有统计学意义(P<0.05).观察组并发症发生率为3.08%(2/65),低于对照组的20.97%(13/62),差异有统计学意义(χ^2=9.75,P<0.05).[结论]腔镜下超声刀食管癌切除术可降低患者疼痛介质、氧化应激产物水平,同时还可优化手术过程,减少术后并发症的发生.  相似文献   
2.

Background

This study investigated the correlation between a history of human papillomavirus (HPV) infection and skin cancer risk.

Materials and Methods

The study cohort comprised 26,919 patients with newly diagnosed HPV infection between 2000 and 2012; with the use of computer-generated numbers, patients without previous HPV infection were randomly selected as the comparison cohort. The patients in the HPV infection cohort were matched to comparison individuals at a 1:4 ratio by demographic characteristics and comorbidities. All study individuals were followed up until they developed skin cancer, withdrew from the National Health Insurance program, were lost to follow-up, or until the end of 2013. The primary outcome was subsequent skin cancer development. Cox proportional hazards regression analysis was used to analyze the risk of skin cancer with hazard ratios (HRs) and 95% confidence intervals (CIs) between the HPV and control cohort.

Results

The adjusted HR of skin cancer for patients with HPV relative to controls was 2.45 after adjusting sex, age and comorbidities. (95% CI, 1.44–4.18, p < .01). The subgroup analysis indicated that a patient with HPV infection had a significantly greater risk of skin cancer if they were aged >40 years. Notably, a risk of skin cancer was found in the group diagnosed with HPV within the first 5 years after the index date (adjusted HR, 3.12; with 95% CI, 1.58–5.54). Sensitivity analysis by propensity score, matching with balanced sex, age, and comorbidities, showed consistent results.

Conclusion

A history of HPV infection is associated with the development of subsequent skin cancer in Taiwanese subjects, and the risk wanes 5 years later.

Implications for Practice

In this Taiwan nationwide cohort study, there was a 2.45-fold increased risk of developing new-onset skin cancers for patients with incident human papillomavirus (HPV) infection, compared with the matched controls. Furthermore, the risk was noticeably significant among patients aged >40 years. A prominent risk of skin cancers was found in the group diagnosed with HPV within the first 5 years after the index date in this study. The results of this analysis may raise consensus on the effect of HPV infection on the risk of skin cancers. Clinicians are encouraged to implement prudently on the differential diagnosis of skin cancers and HPV prevention and treatment, especially in older patients.
  相似文献   
3.
BACKGROUND AND PURPOSE:The coronavirus disease 2019 (COVID-19) pandemic has led to decreases in neuroimaging volume. Our aim was to quantify the change in acute or subacute ischemic strokes detected on CT or MR imaging during the pandemic using natural language processing of radiology reports.MATERIALS AND METHODS:We retrospectively analyzed 32,555 radiology reports from brain CTs and MRIs from a comprehensive stroke center, performed from March 1 to April 30 each year from 2017 to 2020, involving 20,414 unique patients. To detect acute or subacute ischemic stroke in free-text reports, we trained a random forest natural language processing classifier using 1987 randomly sampled radiology reports with manual annotation. Natural language processing classifier generalizability was evaluated using 1974 imaging reports from an external dataset.RESULTS:The natural language processing classifier achieved a 5-fold cross-validation classification accuracy of 0.97 and an F1 score of 0.74, with a slight underestimation (−5%) of actual numbers of acute or subacute ischemic strokes in cross-validation. Importantly, cross-validation performance stratified by year was similar. Applying the classifier to the complete study cohort, we found an estimated 24% decrease in patients with acute or subacute ischemic strokes reported on CT or MR imaging from March to April 2020 compared with the average from those months in 2017–2019. Among patients with stroke-related order indications, the estimated proportion who underwent neuroimaging with acute or subacute ischemic stroke detection significantly increased from 16% during 2017–2019 to 21% in 2020 (P = .01). The natural language processing classifier performed worse on external data.CONCLUSIONS:Acute or subacute ischemic stroke cases detected by neuroimaging decreased during the COVID-19 pandemic, though a higher proportion of studies ordered for stroke were positive for acute or subacute ischemic strokes. Natural language processing approaches can help automatically track acute or subacute ischemic stroke numbers for epidemiologic studies, though local classifier training is important due to radiologist reporting style differences.

There is much concern regarding the impact of the coronavirus disease 2019 (COVID-19) pandemic on the quality of stroke care, including issues with hospital capacity, clinical resource re-allocation, and the safety of patients and clinicians.1,2 Previous reports have shown that there have been substantial decreases in stroke neuroimaging volume during the pandemic.3,4 In addition, acute ischemic infarcts have been found on neuroimaging studies in many hospitalized patients with COVID-19, though the causal relationship is unclear.5,6 Studies like these and other epidemiologic analyses usually rely on the creation of manually curated databases, in which identification of cases can be time-consuming and difficult to update in real-time. One way to facilitate such research is to use natural language processing (NLP), which has shown utility for automated analysis of radiology report data.7 NLP algorithms have been developed previously for the classification of neuroradiology reports for the presence of ischemic stroke findings and acute ischemic stroke subtypes.8,9 Thus, NLP has the potential to facilitate COVID-19 research.In this study, we developed an NLP machine learning model that classifies radiology reports for the presence or absence of acute or subacute ischemic stroke (ASIS), as opposed to chronic stroke. We used this model to quantify the change in ASIS detected on all CT or MR imaging studies performed at a large comprehensive stroke center during the COVID-19 pandemic in the United States. We also evaluated NLP model generalizability and different training strategies using a sample of radiology reports from a second stroke center.  相似文献   
4.
环境内分泌干扰物(EED)广泛存在于日常生活中,是一类可以干扰激素行为的外源性化学物。EED可以结合人体内不同的受体,通过多种机制增强或抑制体内正常的内分泌功能,从而引发多种疾病。多囊卵巢综合征(PCOS)病因复杂,已有研究结果表明PCOS的发生与环境因素有关。相关流行病学和基础实验研究表明,EED参与PCOS的发生、发展,但具体作用机制仍需进一步研究。现就EED与PCOS的关系及可能的相关作用机制进行阐述,总结EED与PCOS的关系,为干预PCOS患者的生活方式并阻断疾病发生提供新的线索。  相似文献   
5.

Cellular arachidonic acid (AA), an unsaturated fatty acid found ubiquitously in plasma membranes, is metabolized to different prostanoids, such as prostacyclin (PGI2) and prostaglandin E2 (PGE2), by the three-step reactions coupling the upstream cyclooxygenase (COX) isoforms (COX-1 and COX-2) with the corresponding individual downstream synthases. While the vascular actions of these prostanoids are well-characterized, their specific roles in the hippocampus, a major brain area for memory, are poorly understood. The major obstacle for its understanding in the brain was to mimic the biosynthesis of each prostanoid. To solve the problem, we utilized Single-Chain Hybrid Enzyme Complexes (SCHECs), which could successfully control cellular AA metabolites to the desired PGI2 or PGE2. Our in vitro studies suggested that neurons with higher PGI2 content and lower PGE2 content exhibited survival protection and resistance to Amyloid-β-induced neurotoxicity. Further extending to an in vivo model, the hybrid of PGI2-producing transgenic mice and Alzheimer’s disease (AD) mice showed restored long-term memory. These findings suggested that the vascular prostanoids, PGI2 and PGE2, exerted significant regulatory influences on neuronal protection (by PGI2), or damage (by PGE2) in the hippocampus, and raised a concern that the wide uses of aspirin in cardiovascular diseases may exert negative impacts on neurodegenerative protection.

Our study intended to understand the crosstalk of prostanoids in the hippocampus, a major brain area impacted in AD, by using hybrid enzymes to redirect the synthesis of prostanoids to PGE2 and PGI2, respectively. Our data indicated that during inflammation, the vascular mediators, PGI2 and PGE2, exerted significant regulatory influences on neuronal protection (by PGI2), or damage (by PGE2) in the hippocampus. These findings also raised a concern that the widely uses of non-steroidal anti-inflammatory drugs in cardiovascular diseases may exert negative impacts on neurodegenerative protection.

  相似文献   
6.
Objective:In-stent restenosis (ISR) after stenting for intracranial stenosis is a significant issue. This study aimed to evaluate the usefulness of the 3D T1-SPACE technique in the follow-up of patients after stent implantation.Methods:Fifteen patients with intracranial arterial stenosis were prospectively enrolled 6–8 months after stenting. Digital subtraction angiography (DSA) and 3D T1-SPACE imaging were performed to evaluate the degree of stenosis and the enhancement of the vessel wall. Bland–Altman plots were used to assess the agreement between the two imaging methods, and the Pearson correlation coefficient was calculated as a measure of the linear correlation.Results:Eight Enterprise stents and seven Wingspan stents were used in 15 patients. The follow-up DSA after 6–8 months showed that the degree of stenosis was 40% (range, 30–72%), and ISR occurred in 4 of 15 (26.7%) lesions. The degree of stenosis assessed using the 3D T1-SPACE imaging technique was 35% (range, 30–75%). All four patients with ISR demonstrated significant enhancement. The Pearson correlation coefficient between the two methods was 0.959 (p < 0.05), and the Bland–Altman plot showed that all data points were within the consistency limits ( x- ± 1.96 s).Conclusion:As a non-invasive imaging modality, 3D T1-SPACE showed great consistency with DSA in measuring the degree of stenosis after intracranial stenting. It may be used as an optional method for detecting ISR.Advances in knowledge:This study evaluated the usefulness of 3D T1-SPACE technique in the follow-up of patients after stent implantation, which could be used as an optional and non-invasive method in detection of in-stent restenosis.  相似文献   
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