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41.
Asbestos related pleuropulmonary disease has been emerging health problem for recent years. It can cause variable clinical symptoms and radiological abnormalities. However, there has been no report for their characteristics in subjects who were environmentally exposed to asbestos. We reviewed the CT images of 35 people who were environmentally exposed to asbestos in Chungnam province, Korea. The study result showed high incidence of pleural plaque and pulmonary fibrosis on chest CT (94% and 77%, respectively). The common CT findings of lung parenchymal lesions were as follows: centrilobular opacities (94%), subpleural dot-like or branching opacities (80%), interlobular septal thickening (57%), intralobular interstitial thickening (46%), parenchymal bands (43%) and subpleural curvilinear line (29%). There were no significant differences in the prevalence of pulmonary fibrosis and pleural plaques according to sex, age and duration of exposure. In conclusion, pleural plaque and pulmonary fibrosis are common asbestos-related CT finding in the exposed people. Asbestos related lung parenchymal CT findings in the participants with environmental exposure show similar to those observed in the occupational exposure.  相似文献   
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Our previous secretin provocation studies in normal volunteers and unoperated duodenal ulcer patients suggested that the gastrin rise in gastrinoma may be an exaggeration of the normal response rather than paradoxical. We report further studies in various clinical settings having normogastrinemia (normal, n = 17; unoperated duodenal ulcer, n = 13; primary hyperparathyroidism, n = 7) and hypergastrinemia (postvagotomy, n = 5; hypochlorhydria, n = 7; achlorhydria, n = 10; chronic renal failure, n = 10; gastrinoma, n = 5). Under all nongastrinoma conditions, there were similar gastrin rises of 9-19% between 2 and 5 min after bolus intravenous GIH secretin (2 CU/kg), which fell to baseline by 8 min, except for chronic renal failure. In chronic renal failure, gastrin remained elevated from 7 to 30 min and was significantly different (p less than 0.05) at 10-30 min compared to all other nongastrinoma conditions except hyperparathyroidism. Peak rises occurred within 5 min in all entities, but only three gastrinoma patients had positive secretin provocation tests by the predefined criterion of a gastrin rise greater than 200 pg/ml. The results of secretin provocation in various clinical entities with and without hypergastrinemia further support the hypothesis that the gastrin rise in gastrinoma is an exaggeration of the normal response. The prolonged gastrin rise seen in chronic renal failure may be due to altered renal clearance, inasmuch as other hypergastrinemic states had responses similar to normal and duodenal ulcer.  相似文献   
44.
Objective: Acute atherosis is a lesion of the spiral arteries characterized by fibrinoid necrosis of the vessel wall, an accumulation of fat-containing macrophages, and a mononuclear perivascular infiltrate, which can be found in patients with preeclampsia, fetal death, small-for-gestational age, spontaneous preterm labor/premature prelabor rupture of membrane, and spontaneous mid-trimester abortion. This lesion is thought to decrease blood flow to the intervillous space which may lead to other vascular lesions of the placenta. The objective of this study was to test whether there is an association between acute atherosis and placental lesions that are consistent with maternal vascular underperfusion (MVU), amniotic fluid infection (AFI), fetal vascular thrombo-occlusive disease (FVTOD) or chronic inflammation.

Material and methods: A retrospective cohort study of pregnant women who delivered between July 1998 and July 2014 at Hutzel Women’s Hospital/Detroit Medical Center was conducted examine 16?457 placentas. The frequency of placenta lesions (diagnosed using the criteria of the Perinatal Section of the Society for Pediatric Pathology) was compared between pregnancies with and without acute atherosis.

Results: Among 16?457 women who were enrolled, 10.2% (1671/16?457) were excluded, leaving 14?786 women who contributed data for analysis. Among them, the prevalence of acute atherosis was 2.2% (326/14?786). Women with acute atherosis were more than six times as likely as those without to have placental lesions consistent with maternal underperfusion (adjusted odds ratio – aOR: 6.7; 95% CI 5.2–8.6). To a lesser degree, acute atherosis was also associated with greater risks of having either lesions consistent with FVTOD (aOR 1.7; 95% CI 1.2–2.3) or chronic chorioamnionitis (aOR 1.9; 95% CI 1.3–3), but not with other chronic inflammatory lesions, after adjusting for gestational age at delivery. In contrast, women with acute atherosis were 60% less likely to have lesions consistent with AFI, adjusting for gestational age at delivery (aOR 0.4; 95% CI 0.3–0.5).

Conclusions: Acute atherosis is associated with increased risks of having placental lesions consistent with MVU, and to a lesser extent, chronic chorioamnionitis and those consistent with FVTOD.  相似文献   
45.
Background/aims The possibility of proximal lesion without distal polyps is a weak point of sigmoidoscopic colon cancer screening, but the clinical significance of distal findings for advanced proximal neoplasm (APN) is uncertain. The aim of this study was to assess the significance of a distal finding as a predictor of APN. Materials and methods Asymptomatic patients ≥50 years old were enrolled from among patients who underwent polypectomy at 11 tertiary medical centers during the Korean Association for the Study of Intestinal Disease prospective study conducted between July 2003 and March 2004. Polyps located distal to the splenic flexure were defined as distal polyps. An advanced neoplasm was defined as a polyp of ≥10 mm in size, and/or with villous features, and/or with high-grade dysplasia, or invasive cancer. Age, gender, and distal polyp size, appearance, and histology were analyzed as risk factors of APN. The sensitivity and positive predictive value of distal polyps for APN were calculated. Results Data from 826 patients were analyzed. Mean patient age was 60.1 years (range 50–86), and 71.3% were men. APN was found in 98 patients, and 45 (45.9%) patients had no distal polyps. Risk factors of APN were a male gender, distal polyp size, and an advanced distal neoplasm. Sensitivities of a distal polyp of ≥10 mm and of an advanced distal neoplasm for APN were both 38.8% with positive predictive values of 13.3 and 14.4%, respectively. Conclusions Although distal colon findings were found to be helpful for predicting APN in asymptomatic patients aged ≥50 years, APN without distal polyps requires careful consideration.  相似文献   
46.
A 70-year-old woman with a known chronic dissecting aneurysm of the descending thoracic aorta presented with new-onset back pain and hemoptysis. The hemoptysis was thought to be the result of invasion of the bronchial tree by the aneurysm. During surgical repair, a lesion that appeared to be a pulmonary abscess was discovered to be adhering to the aortic tissue, and the patient underwent a localized pulmonary resection. The pathology report of the surgical specimens revealed squamous cell carcinoma of the lung with infiltration of the aortic wall. The patient died of lung cancer 6 months later. Hemoptysis was an unusual presentation in a case of lung cancer that had invaded a stable chronic aortic aneurysm.  相似文献   
47.
BackgroundOrbital and peri-orbital venolymphatic malformations (VLM) are low flow vascular malformations. Intralesional bleomycin is now commonly being used to treat such malformations.ObjectiveThe purpose of this systematic review is to synthesize evidence on the safety and efficacy of bleomycin/pingyangmycin sclerotherapy for the treatment of orbital and peri-orbital VLM.MethodsWe searched Medline, Embase, Scopus and Cochrane database for studies reporting outcomes of bleomycin/pingyangmycin sclerotherapy for orbital and peri-orbital VLM between 1974 to April 5th, 2019. Nine retrospective cohort studies enrolling 132 patients were included. Two reviewers independently screened and extracted data and assessed the risk of bias. Predefined outcome measures were subjective and objective reduction of the lesion and associated complications.ResultsSubjective reduction of the lesions was seen in 96.2% of the studies. Objective reduction of the lesion and symptomatic improvement were reported in 91.6 and 95% of the studies respectively. Non responders were 9.0%. Minor adverse events were reported in 18.1% of the studies. Major complications like pulmonary toxicity or pulmonary fibrosis was not encountered in any of the included studies. Quality of evidence was generally low.ConclusionBleomycin/pingyangmycin sclerotherapy is very effective and relatively safe for the treatment of orbital and periorbital VLM and is not associated with any major side effects including pulmonary fibrosis.Limitations: The systematic review is limited mainly due to low quality of the included studies with retrospective design.  相似文献   
48.
BackgroundCombined obstetric and neonatal emergency simulation based training is gaining popularity in healthcare settings. Methods: In this qualitative study, through semi-structured one to one interviews, we evaluated participant attitudes, perceptions of retention of learning, and application to clinical practice one year after a simulation workshop. Audio recordings of interviews were transcribed, collated and subjected to thematic analysis. Results: Five major themes were identified through the thematic analysis: comparing simulation to clinical practice; learning and working in teams; thinking retention and sustainability; relating relevance of simulation based education to roles; and managing leadership. Conclusions: Participants’ acknowledgement of training being relevant to their routine practice, and keenness to learn management of complicated births highlighted the sustained impact of obstetric and neonatal emergency simulation training.  相似文献   
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