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排序方式: 共有2055条查询结果,搜索用时 15 毫秒
1.
Ziora D Sielska-Spytek E Dworniczak S Oklek K Kozielski J 《Pneumonologia i alergologia polska》2002,70(9-10):458-467
The purpose of this study was comparison of VEGF (vascular endothelial growth factor) levels in serum and pleural fluid and estimation of this test usefulness in diagnosis of pleural effusions. VEGF levels were measured by ELISA method in 68 patients (45 males and 23 females) aged 19-81 years. By Light's criteria in 16 cases transudate and in 52 cases exudate was recognized. By means of fluid cytology, pleural biopsy, microbiology or thoracoscopy in 10 cases pleural metastases from distant organs, in 15 cases coexisting pulmonary neoplasm, in 11 cases mesothelioma and in 16 cases tuberculosis were determined as a cause of fluid accumulation in pleural space. The mean VEGF levels were significantly higher (p < 0.001) in patients with exudates than in patients with transudates (3833 pg/ml and 325 pg/ml respectively). Based on likelihood ratios analysis, as a cut off value in differentiation of exudates and transudates a value 700 pg/ml was accepted. The sensitivity of this test was 75% and the specificity 93% and likelihood ratio (LR) 12.5. The mean VEGF level in exudates was seven times higher than mean VEGF level in serum (3833 pg/ml and 573 pg/ml respectively). Mean VEGF levels in malignant exudates (4615 pg/ml) were significantly higher than in tuberculous exudates (2073 pg/ml). As a cut off value in differentiation between malignant and tuberculous exudates a value of 4500 pg/ml was accepted. We conclude that our results suggests the local VEGF production in pleural cavity and the significant role of this cytokine in pleural exudates accumulations and also suggests the usefulness of VEGF estimation in pleural fluid in differentiation transudates from exudates and malignant from tuberculous pleural fluids. 相似文献
2.
Olszyna DP Prins JM Dekkers PE De Jonge E Speelman P Van Deventer SJ Van Der Poll T 《Journal of clinical immunology》1999,19(6):399-405
Chemokines are a superfamily of small chemotactic proteins. While increased levels of interleukin-8 have been measured in serum and urine during urinary tract infection, little is known about other chemokines in this condition. Monocyte chemoattractant protein (MCP)–1, macrophage inflammatory protein (MIP)–1, MIP-1 and interferon- inducible protein (IP)–10 were measured in 30 patients with culture-proven urosepsis during a 3-day follow-up and in 11 healthy humans after intravenous injection of endotoxin (4 ng/kg). Urine and serum levels of MCP-1, MIP-1, and IP-10, but not of MIP-1, were elevated in patients on admission, and decreased after initiation of antibiotic treatment. Endotoxin administration to healthy subjects induced increases in plasma and urine concentrations of all four chemokines. These data indicate that clinical and experimental gram-negative infection in humans is associated with enhanced production of chemokines that act mainly on mononuclear cells and that these chemokines are at least in part locally produced. 相似文献
3.
INTRODUCTION: Previous ex vivo experiments by others suggest that elevated body temperature can prime the respiratory burst of human neutrophils. The mechanism of the priming phenomenon induced by temperature has not been addressed so far. Furthermore, the priming temperature range was not defined. MATERIAL/METHODS: In the present study we explored ,under in vitro conditions, the influence of febrile-range temperatures on reactive oxygen species (ROS)generation by human peripheral blood neutrophils. ROS production was measured using whole.blood luminol-dependent chemiluminescence. Two elements of signal transduction pathways, calcium and p38 mitogen.activated protein kinase alpha (p38MAPKalpha) ,frequently underlying neutrophil priming were also examined.Calcium levels in the cytosol of resting and fMLP. stimulated isolated neutrophils were measured with the Fura-2AM spectrofluorimetric method. The activity of p38MAPKalpha was assessed indirectly with a specific inhibitor of the kinase, SB 203580. RESULTS: The study revealed a priming effect at 38 degrees C toward human peripheral blood neutrophil ROS production. Any concomitant effect on calcium response was not observed. Instead, experiments with SB 203580,a specific inhibitor of p38MAPKalpha, pointed to an increased activity of the kinase as a molecular background of temperature-induced priming. However, the priming effect of temperature was confined to 38 degrees C, while higher temperatures proved to exert no effect (39 and 40 degrees C)or even inhibited ROS generation by neutrophils (43 degrees C). CONCLUSIONS: Our study suggests a heterogeneous influence of temperature on human neutrophil functioning, including the priming of the cells by a low-febrile-range temperature. It also suggests a p38MAPKalpha-dependent molecular background of the priming phenomenon. 相似文献
4.
Splenic metastasis from lung cancer is a rare clinical event, most often diagnosed at the time of an autopsy. We report a case of a 68 year old man with splenic metastasis from the primary lung cancer. Staging procedures before the resection of the primary lung tumor detected the splenic lesion. Upper left lobectomy and splenectomy were done by the left postero-lateral thoracotomy with phrenotomy. The rarity of solitary spleen metastasis from lung cancer and the treatment are discussed. 相似文献
5.
Krzyzak AT Jasiński A Weglarz WP Adamek D Sagnowskil P Baj M 《Acta neurobiologiae experimentalis》2005,65(3):255-264
Magnetic Resonance Diffusion Tensor Imaging (DTI) of the control and traumatic injured spinal cord of a rat in vitro is reported. Experiments were performed on excised spinal cords from 10 Wistar rats, using a home-built 6.4 T MR microscope. MRI and histopathological results were compared. Presented results show that DTI of the spinal cord, perfused with formalin 10 minutes after the injury, can detect changes in water diffusion in white matter (WM) and in gray matter (GM), in areas extending well beyond the region of direct impact. Histology of neurons of the GM shows changes that can be attributed to ischemia. This is in agreement with the observed decrease of diffusion in the injured regions, which may be attributed to the cytotoxic edema due to ischemia. However, the diffusion changes in highly anisotropic WM seem to be caused by a direct action of mechanical force of impact, which significantly distorts the nerve fibers. 相似文献
6.
Treatment with continuous positive airway pressure may affect blood glucose levels in nondiabetic patients with obstructive sleep apnea syndrome 总被引:5,自引:0,他引:5
STUDY OBJECTIVES: Obstructive sleep apnea syndrome (OSAS) is often associated with impaired glucose metabolism. Data on the effects of OSAS treatment with continuous positive airway pressure (CPAP) on blood glucose and insulin resistance are conflicting. The study aimed at assessing the immediate effect of CPAP on glucose control measured with a continuous glucose monitoring system (CGMS). PARTICIPANTS AND MEASUREMENTS: Nine non-diabetes subjects with OSAS (mean age 53.0 +/- 8.0 years; body mass index 34.8 +/- 5.3 kg/m2) underwent 2 overnight polysomnographic examinations: a diagnostic study and one with CPAP treatment. Continuous glucose monitoring system (CGMS) was applied overnight on both occasions. Glucose metabolism was assessed with a 75-g oral glucose tolerance test, plasma insulin and homeostatic model assessment of insulin resistance (HOMA-IR) index. RESULTS: The mean (+/- SD) apnoea-hypopnea index (AHI) at diagnostic polysomnography was 54.3 +/- 29.3 (range 16-81). Fasting plasma insulin levels in patients with OSAS was 84.3 +/- 43.4 pM at baseline, and the HOMA-IR was 3.6 +/- 2.2. CPAP treatment in the subjects with OSAS resulted in a significant reduction in the AHI to 4.5 +/- 7.1. All of the major saturation parameters improved significantly on CPAP. CGMS showed mean glucose values significantly higher during the CPAP night than during the diagnostic night: 80 +/- 11 mg/dL versus 63 +/- 7 mg/dL (P < .01). Fasting insulin and HOMA-IR measured after the CPAP night tended to be higher than at baseline (98.4 +/- 51.0 pmol vs 84.3 +/- 43.4 pmol and 3.9 pmol +/- 2.6 vs 3.6 +/- 2.2 pmol, respectively, P > .05). CONCLUSION: CPAP treatment in nondiabetic obese patients with OSAS may have an immediate elevating effect on blood glucose. 相似文献
7.
Micha Oczkowski Katarzyna Dziendzikowska Anna Pasternak-Winiarska Dariusz Wodarek Joanna Gromadzka-Ostrowska 《Nutrients》2021,13(2)
Due to the constantly increasing number of cases, prostate cancer has become one of the most important health problems of modern societies. This review presents the current knowledge regarding the role of nutrients and foodstuff consumption in the etiology and development of prostate malignancies, including the potential mechanisms of action. The results of several in vivo and in vitro laboratory experiments as well as those reported by the clinical and epidemiological research studies carried out around the world were analyzed. The outcomes of these studies clearly show the influence of both nutrients and food products on the etiology and prevention of prostate cancer. Consumption of certain nutrients (saturated and trans fatty acids) and food products (e.g., processed meat products) leads to the disruption of prostate hormonal regulation, induction of oxidative stress and inflammation, and alteration of growth factor signaling and lipid metabolism, which all contribute to prostate carcinogenesis. On the other hand, a high consumption of vegetables, fruits, fish, and whole grain products exerts protective and/or therapeutic effects. Special bioactive functions are assigned to compounds such as flavonoids, stilbenes, and lycopene. Since the influence of nutrients and dietary pattern is a modifiable risk factor in the development and prevention of prostate cancer, awareness of the beneficial and harmful effects of individual food ingredients is of great importance in the global strategy against prostate cancer. 相似文献
9.
Krzysztof Letachowicz Klaudia Bardowska Tomasz Krlicki Dorota Kamiska Mirosaw Banasik Karolina Zajdel Oktawia Mazanowska Katarzyna Madziarska Dariusz Janczak Magdalena Krajewska 《Renal failure》2021,43(1):113
BackgroundArteriovenous fistulae (AVFs) may remain patent after kidney transplantation (KTx), contributing to maladaptive cardiac remodeling. The flow in AVFs is associated with the diameter of its vessels and thus with the AVF location. The main objective of this study is to assess the influence of AVF location and its patency on the self-reported quality of life (QOL) of kidney transplant recipients (KTRs) with past history of hemodialysis.MethodsTo gain clinical data, during a scheduled visit, 353 KTRs were asked to fill out an anonymous questionnaire. From this group, 284 respondents were found eligible for analysis. The outcome was defined as prevalence of symptoms and health status, measured with the Left Ventricular Dysfunction-36 (LVD-36) Questionnaire in symptomatic patients.ResultsThe hemodialysis patients (n = 243) were divided into two groups according to AVF location, i.e., DAVF – distally located AVF – (n = 174) and PAVF – proximally located AVF – (n = 69). The proportion of patients with heart failure (HF) was higher in PAVF group (24% vs. 12%, p = 0.0482). In the multivariable regression, PAVF, serum creatinine levels, and the presence of HF or coronary artery disease (CAD) remained independent predictors of lower functional capacity. Among patients with heart disease, the presence of active AVF was independently associated with worse functional outcome (higher LVD-36 scores).ConclusionsThe influence of persistent PAVF in KTRs seems to be unfavorable, especially when coexisting with CAD or HF. Abbreviations: AVF arteriovenous fistula; BMI body mass index; CAD coronary artery disease; D-AVF distally-located arteriovenous fistula; EC exercise capacity; HD hemodialysis; HF heart failure; KTx kidney transplantation; KTR kidney transplant recipient; LVD-36 Left Ventricle Disfunction – 36; LVEF left ventricle ejection fraction; LVH left ventricle hypertrophy; NYHA New York Heart Association; P-AVF proximally located arteriovenous fistula; PD peritoneal dialysis; PRO patient-reported outcomes; QOL quality of life. 相似文献
10.
Wojciech Sawczuk Agnieszka Merkisz-Guranowska Dariusz Ulbrich Jakub Kowalczyk Armando-Miguel Rilo Cas 《Materials》2022,15(18)
This paper presents the results of tests on the railway disc brake with regard to the weight wear of friction pads. The tests were carried out at a certified brake test bench where the friction-mechanical characteristics of the railway brake were determined. The test stand was additionally equipped with a thermal imaging camera to observe the contact between the brake pads and the brake disc. The scientific goal of the test is to evaluate the relationship between the weight wear of friction pads and the quantities characterizing the braking process. The quantities characterizing the braking process included pad-to-disc contact area, friction pad thickness, pad-to-disc pressure, and braking speed. A regression model to estimate the friction pad wear on the basis of a single braking with the given input quantities was determined. The greatest influence on the increase in weight wear of friction pads has the braking velocity, which was confirmed by the value of the correlation coefficient of the regression model at value 0.81. The pressure of the friction pad to the disc and the friction pad thickness do not have a significant effect on the weight wear described by the regression model, and the obtained correlation coefficient for these parameters was lower than the value of 0.2. 相似文献