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Bagby  GC Jr; McCall  E; Bergstrom  KA; Burger  D 《Blood》1983,62(3):663-668
Human umbilical vein endothelial cells were cultured in supernatants of peripheral blood monocytes that had been cultured for 3 days with and without lactoferrin. Colony-stimulating activity (CSA) was measured in supernatants of the endothelial cell cultures and appropriate control cultures using normal, T-lymphocyte-depleted, phagocyte-depleted, low- density bone marrow cells in colony growth (CFU-GM) assays. Monocyte- conditioned medium contained a nondialyzable, heat labile factor that enhanced 4-15--fold the production of CSA by endothelial cells. The addition of lactoferrin to monocyte cultures reduced the activity of this monokine by 69%. Lactoferrin did not inhibit CSA production by monokine-stimulated endothelial cells. Therefore, vascular endothelial cells are potent sources of CSA, the production of CSA by these cells is regulated by a stimulatory monokine, and the production and/or release of the monokine is inhibited by lactoferrin, a neutrophil- derived putative feedback inhibitor of granulopoiesis. Inasmuch as a similar monokine is known to stimulate CSA production by fibroblasts and T lymphocytes, we suggest that mononuclear phagocytes play a pivotal role in the regulation of granulopoiesis by recruiting a variety of cell types to produce CSA.  相似文献   
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目的:对比初次和再发骨质疏松性椎体压缩骨折(osteoporotic vertebral compression fractures,OVCFs)患者保 守治疗的生存质量,了解再次骨折对此类患者生存质量各方面的影响。方法:回顾性观察治疗OVCFs后出现再骨折 的患者30名(再骨折组)和同时期行保守治疗OVCFs后未发生再骨折的基本条件相似的患者30例(对照组),比较两组出 院后3个月时SF-36简明健康健康状况调查表的调查结果。结果:再骨折组治疗后的8个维度均不同程度较对照组变差 (均P<0.01)。结论:再骨折组患者的生存质量明显低于对照组,并且会进一步影响患者的心理预期、情绪和社会活动 的各个方面。  相似文献   
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Background

Three manometric subtypes of achalasia were defined in the Chicago Classification approximately 10 years ago: type I (aperistalsis), type II (pan-pressurization), and type III (spastic). Since the widespread use of this classification scheme, the evolving prevalence of these subtypes has not been elucidated. We aim to determine the prevalence of each subtype a decade after the adoption of the Chicago Classification.

Methods

This is a retrospective cohort analysis of patients diagnosed with achalasia on high-resolution manometry (HRM) at two major academic medical centers between 2015 and 2018. Patients were excluded if they had a diagnosis of another esophageal motility disorder, previously treated achalasia, or foregut surgery. Demographic data, manometric subtype, and esophageal dilatation grade on endoscopy were obtained. Prevalence of achalasia subtypes was compared with a published historical control population (2004–2007). Fischer’s exact and t tests were used for analysis.

Results

Of 147 patients in the contemporary cohort and 99 in the historical control cohort, the prevalence of type I achalasia was 8% versus 21%, type II 63% versus 50%, and type III 29% versus 29%, respectively (p?=?0.01). The mean age in our population was 58 years compared to 57 years in the historical control, and the proportion of men 48% versus 47%, respectively (p?=?0.78). Mean endoscopic dilatation grade in the contemporary cohort was 1.5 for type I patients, 0.9 for type II, and 0.4 for type III, compared with 1.5, 0.6, and 0.4, respectively. Overall mean dilatation grade was 0.8 in our cohort versus 0.7 in the historical control (p?=?0.58).

Conclusion

The prevalence of type II achalasia was significantly greater and prevalence of type I significantly less in our patient population compared to our predefined historical control. Other characteristics such as age and sex did not appear to contribute to these differences. Histopathological evidence has suggested that type II achalasia may be an earlier form of type I; thus, the increased prevalence of type II achalasia may be related to earlier detection of the disease. The adoption of HRM, widespread use of the Chicago Classification, and increased disease awareness in the past decade may be contributing to these changes in epidemiology.

  相似文献   
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Digestive Diseases and Sciences - Patients with SARS-CoV-2 who present with gastrointestinal symptoms have a milder clinical course than those who do not. Risk factors for severe COVID-19 disease...  相似文献   
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To determine the phenotype and natural history of a founder genetic subtype of autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVC) caused by a p.S358L mutation in TMEM43. The age of onset of cardiac symptoms, clinical events and test abnormalities were studied in 412 subjects (258 affected and 154 unaffected), all of which occurred in affected males significantly earlier and more often than unaffected males. Affected males were hospitalized four times more often than affected females (p ≤ 0.0001) and died younger (p ≤ 0.001). The temporal sequence from symptoms onset to death was prolonged in affected females by 1–2 decades. The most prevalent electrocardiogram (ECG) manifestation was poor R wave progression (PRWP), with affected males twice as likely to develop PRWP as affected females (p ≤ 0.05). Left ventricular enlargement (LVE) occurred in 43% of affected subjects, with 11% fulfilling criteria for dilated cardiomyopathy. Ventricular ectopy on Holter monitor was common and occurred early: the most diagnostically useful clinical test. No symptom or test could rule out diagnosis. This ARVC subtype is a sex‐influenced lethal arrhythmogenic cardiomyopathy, with a unique ECG finding, LV dilatation, heart failure and early death, where molecular pre‐symptomatic diagnosis has the greatest clinical utility.  相似文献   
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