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981.
Clinical Oral Investigations - The advantages of nasal high-flow oxygen therapy (NHF) include not only allowing talking, but also eating and drinking, during the therapy. However, the effect of NHF...  相似文献   
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984.
To clarify the effect of secretory IgA (sIgA) deficiency on gut homeostasis, we examined intraepithelial lymphocytes (IELs) in the small intestine (SI) of polymeric immunoglobulin receptor-deficient (pIgR−/−) mice. The pIgR−/− mice exhibited the accumulation of CD8αβ+ T-cell receptor (TCR)-αβ+ IELs (CD8αβ+αβ-IELs) after weaning, but no increase of CD8αβ+γδ-IELs was detected in pIgR−/− TCR-β−/− mice compared with pIgR+/+ TCR-β−/− mice. When 5-bromo-2′-deoxyuridine (BrdU) was given for 14 days, the proportion of BrdU-labelled cells in SI-IELs was not different between pIgR+/+ mice and pIgR−/− mice. However, the proportion of BrdU-labelled CD8αβ+-IELs became higher in pIgR−/− mice than pIgR+/+ mice 10 days after discontinuing BrdU-labelling. Intravenously transferred splenic T cells migrated into the intraepithelial compartments of pIgR+/+ TCR-β−/− mice and pIgR−/− TCR-β−/− mice to a similar extent. In contrast, in the case of injection of immature bone marrow cells, CD8αβ+αβ-IELs increased much more in the SI of pIgR−/− TCR-β−/− mice than pIgR+/+ TCR-β−/− mice 8 weeks after the transfer. αβ-IELs from pIgR−/− mice could produce more interferon-γ and interleukin-17 than those of pIgR+/+ mice, and intestinal permeability tended to increase in the SI of pIgR−/− mice with aging. Taken together, these results indicate that activated CD8αβ+αβ-IELs preferentially accumulate in pIgR−/− mice through the enhanced differentiation of immature haematopoietic precursor cells, which may subsequently result in the disruption of epithelial integrity.  相似文献   
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BACKGROUND: The posterior right atrial transverse conduction capability during typical atrial flutter (AFL) is well known, but its relationship to the anatomical characteristics remains controversial. METHODS AND RESULTS: Thirty-four AFL and 16 controls underwent intracardiac echocardiography after placement of a 20-polar catheter at the posterior block site during AFL or pacing. In 31 patients, the effective refractory period (ERP) at the block site was determined as the longest coupling interval that resulted in double potentials during extrastimuli from the mid-septal (SW) and free (FW) walls. The block site was located 3.0-29.0 mm posterior to the crista terminalis (CT) in each AFL and control patient. The CT area indexed to the body surface area was larger in AFL patients than in control patients (16.4+/-6.5 mm(2)/m(2) vs 11.3+/-6.4 mm(2)/m(2), p=0.01), and was positively correlated to age (r=0.34, p=0.02). The ERP was longer in the AFL patients than in controls (SW: median value 600 [270-725] ms vs 220 [200-253] ms; FW: 280 [230-675] ms vs 215 [188-260] ms, p<0.05 for each). CONCLUSIONS: A functional block line was located on the septal side of the CT in all patients. A limited conduction capability and age-related CT enlargement might have important implications for the pathogenesis in AFL.  相似文献   
987.
Aim. In this study, we investigated the tissue expression of Survivin, p53, and Bcl-2 in intraductal papillary-mucinous tumor (IPMT) of the pancreas to identify their roles in tumorigenesis of IPMT, and examined their correlations with tumor cell apoptosis and proliferation in IPMT. The diagnostic values of the expression of Survivin, p53, and Bcl-2 and the apoptotic index (AI) and Ki-67 labeling index (Ki-67 LI) in IPMT were also examined. Methods. Twenty-two lesions from 17 patients with IPMT, including 12 benign (IPMT Adenoma) and 10 malignant (IPMT Carcinoma In Situ [CIS] (n=4) and Invasive IPMT (n=6) lesions, were immunostained for Survivin, p53, Bcl-2 and Ki-67. The apoptotic cells were detected by the Apop Tag? In Situ Oligo Ligation (ISOL) method. Results. The immunoreactivities for Survivin and p53 significantly increased in the transition from IPMT Adenoma to IPMT CIS (p<0.05 for both). This transition was associated with a significant decrease in tumor cell apoptosis (p<0.001). The expression of Survivin was significantly associated with AI in IPMT (p<0.01), but not with Ki-67 LI. The expressions of Survivin and p53, and AI and Ki-67 LI were also significantly different between benign IPMT and malignant IPMT. Bcl-2 was not expressed in IPMT. Conclusion. These results suggest that Survivin and p53 may play important roles in the transition from IPMT Adenoma to IPMT CIS. This transition is accompanied by a significant decrease in tumor cell apoptosis. Survivin is significantly associated with the change in AI in IPMT. The immunohistochemical detection of Survivin and p53 as well as the determination of the AI and Ki-67 LI have useful roles in the diagnosis of IPMT.  相似文献   
988.
The klotho gene, originally identified by insertional mutagenesis in mice, suppresses the expression of multiple aging-associated phenotypes. This gene is predominantly expressed in the kidney. Recent studies have shown that expression of renal klotho gene is regulated in animal models of metabolic diseases and in humans with chronic renal failure. However, little is known about the mechanisms and the physiological relevance of the regulation of the expression of the klotho gene in the kidney in some diseased conditions. In the present study, we first investigated the role of angiotensin II in the regulation of renal klotho gene expression. Long-term infusion of angiotensin II downregulated renal klotho gene expression at both the mRNA and protein levels. This angiotensin II-induced renal klotho downregulation was an angiotensin type 1 receptor-dependent but pressor-independent event. Adenovirus harboring mouse klotho gene (ad-klotho, 3.3x10(10) plaque forming units) was also intravenously administered immediately before starting angiotensin II infusion in some rats. This resulted in a robust induction of Klotho protein in the liver at day 4, which was still detectable 14 days after the gene transfer. Ad-klotho gene transfer, but not ad-lacZ gene transfer, caused an improvement of creatinine clearance, decrease in urinary protein excretion, and amelioration of histologically demonstrated tubulointerstitial damage induced by angiotensin II administration. Our data suggest that downregulation of the renal klotho gene may have an aggravative role in the development of renal damage induced by angiotensin II, and that induction of the klotho gene may have therapeutic possibilities in treating angiotensin II-induced end organ damage.  相似文献   
989.
The relationship between silicosis and tuberculosis is well known. Also other mycobacteria such as Mycobacterium kansasii often occur in association with pneumoconiosis. However, there are few reports describing an association of M. avium-intracellulare complex (MAC) lung disease and pneumoconiosis. The purpose of the present study is to describe clinical features of MAC respiratory infection associated with pneumoconiosis. Eleven patients with MAC respiratory infection associated with pneumoconiosis (all men, 6 with silicosis and 5 with welders' pneumoconiosis) were collected. A determination of whether or not MAC caused pulmonary disease was made using the 1997 criteria required by the American Thoracic Society. Radiologically, cavity formation as well as upper lung field predominance of MAC disease were observed in 8 of 11 cases (72.7%). Two of 11 patients died of respiratory failure. Our present study clearly demonstrates that clinical features of MAC respiratory infection associated with pneumoconiosis were different from MAC without underlying diseases.  相似文献   
990.
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