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101.
Pituitary - Non-osmotic stimulation tests using glucagon, arginine, or macimorelin were recently evaluated for their ability to assess posterior pituitary function. Glucagon and arginine, but not...  相似文献   
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OBJECTIVES: The aim of this study was to investigate whether myocardial inflammation (MC) and endothelial activation are associated with clinically detectable endothelial dysfunction. BACKGROUND: In patients with MC, immunohistologic evaluation of myocardial biopsies demonstrates a cellular infiltrate of lymphocytes in the myocardium and endothelial activation, as indicated by enhanced expression of human leukocyte antigen (HLA)-1, HLA-DR and intercellular adhesion molecule (ICAM)-1. This chronic inflammatory process may be associated with endothelial dysfunction. METHODS: In 65 patients with suspected MC, endothelial function of the radial artery was noninvasively assessed. By means of high-resolution ultrasound, diameter changes in response to reactive hyperemia (endothelium-dependent), as compared with glyceroltrinitrate (endothelium-independent), were analyzed. In the myocardial biopsies, MC was confirmed by immunohistology in 53 patients; 12 patients with normal myocardial biopsies served as controls. Endothelial expression of HLA-1, HLA-DR and ICAM-1 was semiquantitatively evaluated by immunohistology. To minimize other factors influencing endothelial function, patients with coronary artery disease, diabetes, severely impaired left ventricular function or more than one arteriosclerotic risk factor were excluded from this study. RESULTS: Endothelial function, as determined by flow-mediated vasodilation (FMD), in patients with MC was impaired (FMD(MC) 4.28%), as compared with controls (FMD(Co) 10.10%). The severity of endothelial dysfunction in patients with MC correlated significantly with the extent of endothelial expression of HLA-1, HLA-DR and ICAM-1 in myocardial biopsies. Endothelium-independent vasodilation was not affected by MC or endothelial activation. CONCLUSIONS: Myocardial inflammation is associated with endothelial dysfunction of peripheral arteries. The severity of endothelial dysfunction correlates with the extent of endothelial activation.  相似文献   
104.
Selective COX-2 inhibitors have been shown to produce fewer gastrointestinal adverse reactions than classical NSAIDs. Nevertheless, these new agents may worsen and delay the healing of experimentally induced gastric ulcers in animals. In this study, we compared the effects of a selective COX-2 inhibitor (celecoxib), a preferential COX-1 inhibitor (piroxicam), and a nonnarcotic analgesic (metamizol) on normal gastric mucosa of rats and, on the other hand, in a setting of preexisting acute gastric lesions induced by 0.6 N hydrochloric acid. Under normal conditions, only piroxicam produced appreciable gastric lesions. However, after acid challenge the three assayed drugs induced significant macroscopic and microscopic damage. Myeloperoxidase activity as an index of neutrophil infiltration was elevated with celecoxib and piroxicam on normal gastric mucosa. On inflamed mucosa, celecoxib augmented enzymatic activity at the lower dose, which was parallelled by an increase in the interleukin 1beta level. Acid instillaton produced a significant rise in PGE2 content at 7 hr. Drug treatment after acid challenge decreased prostaglandin values in all cases, although to a lesser extent than after single drug dose administration. COX-2 mRNA expression was visible 1 hr after acid application, whereas COX-2 protein could only be detected at 7 hr. Piroxicam increased both expression levels. All NSAIDs enhanced transforming growth factor alpha and epidermal growth factor receptor immunoreactivity around the acid-induced lesions. It is concluded that selective COX-2 inhibitors, like conventional NSAIDs, impair the healing of gastric damage, and therefore special attention should be paid in patients with gastric pathologies.  相似文献   
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The concept of asthma and COPD as separate conditions has been questioned, and the term asthma–COPD overlap syndrome has been introduced. We assessed the prevalence, symptoms, and lifestyle factors of asthma–COPD overlap (ACO) in a large Norwegian population-based study.

From 2006 to 2008, a total of 50,777 residents of Nord-Trøndelag participated in the Nord-Trøndelag Health Study, Norway. They completed questionnaires regarding respiratory symptoms, disease status, and medication use. We estimated the prevalence and 95% confidence intervals of ACO. Additionally, spirometry was used to estimate the prevalence of ACO in a subgroup.

The prevalence of self-reported ACO was 1.9%, and in age groups <40, 40–60 and ≥60 years it was 0.7%, 1.4%, and 3.2%, respectively. Among those reporting COPD, the proportion of ACO was 0.56. In the spirometry subgroup when ACO was defined as doctor diagnosed asthma ever and FEV1/FVC < 0.70, the prevalence of ACO was 2.0%. All respiratory symptoms, separately or in combination, as well as medication use were reported most frequently in those with ACO compared to the other groups. Strikingly, we observed a two-fold higher proportion of allergic rhinitis in ACO compared to COPD only.

In this Norwegian population, the prevalence of self-reported ACO was 1.9%, and the corresponding proportion of ACO among those with COPD was 0.56. Participants with ACO generally had the highest proportions of respiratory symptoms compared to asthma or COPD.  相似文献   

107.
Lyme disease is a debilitating infection that is caused upon a bite of Borrelia burgdorferi (Bb)-infected ticks. One of the most prominent clinical manifestations is the development of chronic Lyme arthritis. Months after Bb infection, ~60% of untreated Lyme patients experience intermittent arthritic attacks that may last for years. The use of the CD28?/? mouse in Bb infection has helped to shed light into the mechanisms that govern this inflammatory process, which seems to be tightly regulated. In this current review, the effect of immunoregulation, as well as CD28 deficiency in the development of chronic Lyme arthritis is discussed.  相似文献   
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A prenatally diagnosed fetus with hypoplastic left heart syndrome and intact atrial septum was delivered in the cardiac catheterization suite. Using radio frequency energy, a transseptal perforation of the thickened and intact atrial septum was immediately performed following transcatheter cannulation of the right atrium via the umbilical vein. Serial cutting balloon septostomies followed by static balloon septostomies resulted in effective left atrial decompression, atrial mixing, and optimal pulmonary and systemic perfusion. The child is now thriving after both stage I Norwood and bidirectional Glenn procedures.  相似文献   
110.
The performance of biodegradable knitted and rolled 3‐dimensional (3D) polylactide‐based 96/4 scaffolds modified with bioactive glass (BaG) 13‐93, chitosan and both was compared with regard to the viability, proliferation and chondrogenic differentiation of rabbit adipose stem cells (ASCs). Scaffold porosities were determined by micro‐computed tomography (μCT). Water absorption and degradation of scaffolds were studied during 28‐day hydrolysis in Tris‐buffer. Viability, number and differentiation of ASCs in PLA96/4 scaffolds were examined in vitro. The dimensions of the scaffolds were maintained during hydrolysis and mass loss was detected only in the BaG13‐93 containing scaffolds. ASCs adhered and proliferated on each scaffold type. Cell aggregation and expression of chondral matrix components improved in all scaffold types in chondrogenic medium. Signs of hypertrophy were detected in the modified scaffolds but not in the plain PLA96/4 scaffold. Chondrogenic differentiation was most enhanced in the presence of chitosan. These findings indicate that the plain P scaffold provided a good 3D‐matrix for ASC proliferation whereas the addition of chitosan to the PLA96/4 scaffold induced chondrogenic differentiation independent of the medium. Accordingly, a PLA96/4 scaffold modified by chitosan could provide a functional and bioactive basis for tissue‐engineered chondral implants. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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