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61.
Colloidal gold marker was present in the capillary lumen and at various stages of pinocytosis and passage through the endothelial cells. It was occasionally located in the peri-endothelial space, close to the basement membrane. The uptake of marker by other cells was not observed. These results suggest the existence of two barriers, the biological (pinocytotic and hydrolytic capacities of the endothelial cells) and mechanical (permeability of the basement membrane).  相似文献   
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Consumption of soya-based nutrients is increasing in modern society because of their potentially protective effects against chronic diseases. Soya products are also heavily advertised as alternative drugs for relief from symptoms of the menopause and for hormone replacement therapy. However, because of their oestrogenic activity, negative effects of isoflavones have been postulated. Therefore, we analysed influences of soya isoflavones, major soya constituents with endocrine activity, on thyroxine (T4) binding to its distribution proteins. Serum binding of (125)I-labelled L-T4 was analysed in the absence or presence of increasing concentrations of soya isoflavones using non-denaturing PAGE for analysis. Complete displacement of [(125)I]T4 binding to transthyretin (TTR) was observed in human serum incubated with genistein at concentrations >10 microM; interference started at >0.1 microM. Glycitein showed decreased and daidzein the lowest displacement potency. [(125)I]T4 was displaced to albumin in rat and to T4-binding globulin in human serum. Soya isoflavones also obstruct [(125)I]T4 binding to TTR in human cerebrospinal fluid (CSF). The inhibitory effect was confirmed in direct binding assays using purified TTR with 50% inhibitory concentration values of 0.07 microM for genistein, 0.2 microM for glycitein and 1.8 microM for daidzein. The present study underlined a potent competition of soya isoflavones for T4 binding to TTR in serum and CSF. Isoflavones might alter free thyroid hormone concentrations resulting in altered tissue availability and metabolism. As a consequence of this interference, one could expect a disturbance in the feedback regulation of hormonal networks, including the pituitary-thyroid-periphery axis during development and in adult organisms.  相似文献   
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We reviewed our initial institutional experience with the use of stereotactic hypofractionated radiation therapy (SFRT) in patients with stage I non-small cell lung cancer (NSCLC). Thirty patients with inoperable stage I non-small cell lung cancer due to a severe chronic obstructive pulmonary disease (COPD) and/or chronic heart disease (Eastern Cooperative Oncology Group (ECOG) performance status of 0-2) were treated between December 2000 and October 2003 with SFRT in curative intent. Infiltration of locoregional lymph nodes and distant metastases were ruled out by computerized tomography (CT) scan of the brain, thorax, and abdomen, and by whole body FDG-positron emission tomography scan in all patients. Total RT doses ranged from 24.0 to 37.5 Gy, given in 3-5 fractions to the 60% isodose encompassing the planning target volume. Immobilization was carried out by a vacuum couch and a low-pressure foil. The clinical target volume was the tumor as it appeared in lung windowing on lung CT scan. Organ movements (caused by breathing; range, 6-22 mm) and reproducibility of patient positioning in the couch (range, 3-12 mm) were calculated by sequential CT and orthogonal films. The individual values were taken into account as a safety margin for the definition of the planning target volume (PTV). The median follow-up of living patients is 18 months (range, 6-38 months). As maximum response, there were 10 (33%) complete responses (CRs) and 14 (47%) partial responses (PRs), resulting in a total response rate of 80%. Stable disease was observed in 6 (20%) patients, while no patient experienced progressive disease. During follow-up, 2 (7%) local recurrences were observed (after 17 and 18 months, respectively). Of 5 (17%) patients who developed distant metastasis, 1 patient developed it in liver (3 months), another one in brain (6 months), and another one in the lung (36 months), while 2 patients developed it in mediastinal lymph nodes (after 8, and 11 months, respectively) only. Of 9 (30%) patients who have died, only 3 (10%) died of cancer, while 6 (20%) died of cancer-unrelated or unknown causes. Acute side effects were mild and affected 9 (33%) patients during the RT course (fatigue being the most frequent one in 6 patients). There were 22 acute events occurring in 19 (63%) patients during the first 3 months post-SFRT, the most frequent one being pneumonitis observed in 14 (46%) patients. However, there was only one (3%) grade 3 acute toxicity and no patient experienced greater than grade 3 toxicity during this study. One (3%) patient experienced rib fracture as the late event. SFRT is a feasible and safe treatment method in inoperable patients with stage I NSCLC having reduced lung capacity. Longer follow-up is necessary to get robust data on late toxicity as well as survival.  相似文献   
66.
We present a case of long-term survival of a patient who underwent living-donor liver transplantation for unresectable liver metastases of colon cancer. Two years after left hemicolectomy and subsequent to repeated liver resections, this patient presented with unresectable metastatic disease confined to the liver. She was offered a living-donor liver transplantation, and her husband agreed to be the donor. Five years after transplant, she was alive and recurrence free.  相似文献   
67.
Abnormalities of cerebral white matter, oligodendrocytes, and myelin have been observed in schizophrenia with in-vivo imaging and post-mortem biochemistry. White-matter abnormalities are also frequently associated with cognitive impairment in both healthy and diseased individuals, and cognitive dysfunction is an important component of schizophrenia. While many studies have documented these associations, only a handful have examined the role of white matter in cognitive function in schizophrenia. In this paper, we explore what is known about white-matter deficits in relation to schizophrenia, cognitive deficits, or both together, in order to generate a theoretical model for the role that compromise of white matter might play in producing cognitive impairment in schizophrenia.  相似文献   
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Systemic inflammation in patients with COPD and pulmonary hypertension   总被引:5,自引:0,他引:5  
Joppa P  Petrasova D  Stancak B  Tkacova R 《Chest》2006,130(2):326-333
STUDY OBJECTIVES: COPD is a systemic disorder that is associated with increases of inflammatory proteins in systemic circulation. However, no data on the potential role of systemic inflammation in pulmonary hypertension secondary to COPD are available. Therefore, our aim was to investigate the degree of systemic inflammation reflected by circulatory levels of C-reactive protein (CRP), tumor-necrosis factor (TNF)-alpha, and interleukin (IL)-6 in COPD patients with and without pulmonary hypertension. DESIGN: Cross-sectional study. SETTING: University hospital, tertiary referral setting. PATIENTS AND MEASUREMENTS: In 43 consecutive patients with COPD (mean [+/- SD] age, 65.0 +/- 10.5 years; mean FEV(1), 46.2 +/- 18.1% predicted), lung function was assessed using body plethysmography; pulmonary artery pressure (Ppa) levels were measured by echocardiography. Serum TNF-alpha and IL-6 levels were assessed by enzyme-linked immunosorbent assay, and high-sensitivity serum CRP levels were measured by chemiluminescent immunoassay. RESULTS: Pulmonary hypertension was present in 19 patients and was absent in 24 patients. In patients with pulmonary hypertension, serum CRP and TNF-alpha levels were significantly higher than in those patients without hypertension (median, 3.6 mg/L [25th to 75th percentile, 1.4 to 13.0 mg/L] vs 1.8 mg/L [25th to 75th percentile, 0.8 to 2.8 mg/L; p = 0.034]; and median, 4.2 pg/mL [25th to 75th percentile, 3.4 to 10.9 pg/mL] vs 3.1 pg/mL [25th to 75th percentile, 2.1 to 4.2 pg/mL]; p = 0.042, respectively). No differences were seen in serum IL-6 (median, 10.4 pg/mL [25th to 75th percentile, 8.8 to 12.2 pg/mL] vs 10.5 pg/mL [25th to 75th percentile, 9.4 to 39.1 pg/mL]; p = 0.651) between the groups. In multiple linear regression analysis, the following two variables were independent predictors of systolic Ppa (R(2) = 0.373): Pao(2) (p = 0.011); and log-transformed serum CRP level (p = 0.044). CONCLUSION: We conclude that increases in Ppa in patients with COPD are associated with higher serum levels of CRP and TNF-alpha, raising the possibility of a pathogenetic role for low-grade systemic inflammation in the pathogenesis of pulmonary hypertension in COPD patients.  相似文献   
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