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排序方式: 共有765条查询结果,搜索用时 15 毫秒
41.
Associations of dietary fiber with glucose metabolism in nondiabetic relatives of subjects with type 2 diabetes: the Botnia Dietary Study 总被引:4,自引:0,他引:4
Ylönen K Saloranta C Kronberg-Kippilä C Groop L Aro A Virtanen SM;Botnia Dietary Study 《Diabetes care》2003,26(7):1979-1985
OBJECTIVE: To study cross-sectional associations of dietary fiber intake with insulin resistance, insulin secretion, and glucose tolerance in a population at high risk for type 2 diabetes. RESEARCH DESIGN AND METHODS: The subjects consisted of 248 male and 304 female adult nondiabetic relatives of patients with type 2 diabetes. Dietary intake was measured by means of two 3-day food records. Associations of total, water-insoluble, and water-soluble fiber with measures of glucose metabolism based on an oral glucose tolerance test, were analyzed by multiple linear regression analysis adjusting for sex, age, length of education, physical activity, BMI, waist-to-hip ratio, systolic blood pressure, and serum triglyceride and HDL cholesterol concentrations. The homeostasis model assessment insulin resistance index, the incremental 30-min serum insulin concentration divided by the incremental 30-min glucose concentration, and fasting and 2-h glucose concentrations were the outcome variables. RESULTS: The dietary intake of total as well as water-insoluble and water-soluble fiber was inversely associated with insulin resistance: -0.17 (0.07), P = 0.012; -0.15 (0.07), P = 0.024; and -0.14 (0.07), P = 0.049 [regression coefficients (SE)]. Fiber variables were unrelated to insulin secretion and plasma glucose concentrations. CONCLUSIONS: The results support evidence that a high intake of dietary fiber is associated with enhanced insulin sensitivity and therefore may have a role in the prevention of type 2 diabetes. 相似文献
42.
Effects of exposure to vehicle exhaust on health 总被引:3,自引:0,他引:3
U Ulfvarson R Alexandersson L Aringer E Svensson G Hedenstierna C Hogstedt B Holmberg G Rosén M Sorsa 《Scandinavian journal of work, environment & health》1987,13(6):505-512
Exposure to combustion engine exhaust and its effect on crews of roll-on roll-off ships and car ferries and on bus garage staff were studied. The peak concentrations recorded for some of the substances studied were as follows: total particulates (diesel only) 1.0 mg/m3, benzene (diesel) 0.3 mg/m3, formaldehyde (gasoline and diesel) 0.8 mg/m3, and nitrogen dioxide (diesel) 1.2 mg/m3. The highest observed concentration of benzo(a)pyrene was 30 ng/m3 from gasoline and diesel exhaust. In an experimental study volunteers were exposed to diesel exhaust diluted with air to achieve a nitrogen dioxide concentration of 3.8 mg/m3. Pulmonary function was affected during a workday of occupational exposure to engine emissions, but it normalized after a few days with no exposure. The impairment of pulmonary function was judged to have no appreciable, adverse, short-term impact on individual work capacity. In the experimental exposure study, no effect on pulmonary function was observed. Analyses of urinary mutagenicity and thioether excretion showed no sign of exposure to genotoxic compounds among the occupationally exposed workers or among the subjects in the experimental study. 相似文献
43.
AIMS: Matrix metalloproteinases (MMPs) are involved in tissue remodelling, which is one of the important aspects of inflammatory disease. To assess the balance between the matrix degradation and production, we analysed the in situ expression of MMP-1, -3, -8 and -9, tissue inhibitor of metalloproteinases (TIMP)-1 and -2, and type I procollagen (PC-I) in inflammatory bowel disease. Methods and results: Immunohistochemistry using frozen sections was performed in 17 patients with ulcerative colitis (UC) and 16 with Crohn's disease (CD). In both UC and CD, MMPs and TIMPs were expressed by inflammatory cells as well as by fibroblastic cells most prominently in actively inflamed areas in ulcer bases, but sparsely in intact inflamed mucosa in both UC and CD. In UC, inflamed mucosa with erosions expressed these substances focally. Fibroblasts also expressed PC-I. We identified that vascular smooth muscle cells of venules in ulcer bases expressed MMP-1 and -9, TIMP-1 and PC-I. These venules also expressed E-selectin, a cell adhesion molecule to facilitate the leucocyte extravasation, and vascular endothelial growth factor (VEGF) receptor 2, consistent with their property of newly formed vessels. CONCLUSIONS: Our results suggest that MMPs are involved in the tissue remodelling, angiogenesis and promotion of leucocyte extravasation in the actively inflamed area in the ulcer base in both UC and CD. MMP-1 expression in the mucosa may be related to the initial step of ulceration in UC. Therapeutic manipulation of extracellular matrix turnover would be an effective therapy to alleviate active inflammation and accelerate ulcer healing. 相似文献
44.
Inhibitory effect of cephalothin on matrix metalloproteinase activity around loose hip prostheses. 总被引:1,自引:0,他引:1 下载免费PDF全文
S Santavirta M Takagi Y T Konttinen T Sorsa A Suda 《Antimicrobial agents and chemotherapy》1996,40(1):244-246
The inhibitory effects of drugs on matrix metalloproteinase (MMP) activity in tissues around sites of loose total hip arthroplasty (THA) prostheses were studied. For activity measurements, a DNP-S (dinitrophenyl-Pro-Gln-Gly-Ile-Ala-Gly-Gln-D-Arg) peptide degradation assay was performed by means of high-performance liquid chromatography. Neutral salt tissue extracts revealed significantly elevated MMP activity in THA samples compared with that in noninflamed synovial tissue from the knee joint. This elevation was markedly inhibited by cephalothin, but not by doxycycline, tetracycline, or gentamicin. These results indicate that cephalothin can inhibit MMP activity in reactive periprosthetic tissue and thus reduce, by a nonantimicrobial mechanism, the tissue destruction associated with the loosening of THA implants. 相似文献
45.
Doxycycline in the protection of serum alpha-1-antitrypsin from human neutrophil collagenase and gelatinase. 总被引:5,自引:1,他引:5 下载免费PDF全文
T Sorsa O Lindy Y T Konttinen K Suomalainen T Ingman H Saari S Halinen H M Lee L M Golub J Hall et al. 《Antimicrobial agents and chemotherapy》1993,37(3):592-594
The concentration of doxycycline required to inhibit 50% (50% inhibitory concentration for serpinase activity) of alpha-1-antitrypsin degradation by purified neutrophil collagenase was found to be approximately 20 microM, a value similar to the 50% inhibitory concentration of doxycycline required to inhibit collagen degradation by neutrophil collagenase. Doxycycline also efficiently inhibited phorbol myristate acetate-triggered neutrophil-mediated degradation of alpha-1-antitrypsin. This suggests that doxycycline can protect alpha-1-antitrypsin from collagenase and gelatinase in the presence of other proteases and biologically active molecules that are released by triggered neutrophils. The protection of a body's alpha-1-antitrypsin shield from serpinolytic activity of collagenase and matrix metallproteinases can result in inhibition of serine proteases such as neutrophil elastase. Tetracyclines may thus protect matrix constituents from a wider spectrum of neutral proteases than previously recognized, not just from the matrix metalloproteinases collagenase and gelatinase. 相似文献
46.
The recommended treatment for severe hypothermia with circulatory collapse is re-warming using cardiopulmonary by-pass. This may require transporting a patient to hospital with on-going cardiopulmonary resuscitation (CPR). Manual CPR during patient transport may result in sub-optimal chest compressions and can be a hazard for the ambulance crew. We report a case of a patient with a core temperature of 22.2 degrees C and crew-witnessed cardiac arrest due to hypothermia. After unsuccessful initial resuscitation he was transported to hospital for re-warming with cardiopulmonary by-pass. CPR was continued during transport using a mechanical active compression-decompression device (the LUCAS-device). During cardiopulmonary by-pass ROSC was achieved after 90 min of cardiac arrest. The patient recovered with a cerebral performance category of 3. Using a mechanical device for chest compressions during transport of a hypothermic patient with on-going CPR is feasible, effective and safe. 相似文献
47.
Kiviniemi AM Tulppo MP Wichterle D Hautala AJ Tiinanen S Seppänen T Mäkikallio TH Huikuri HV 《Annals of medicine》2007,39(1):54-62
BACKGROUND: Various indexes of 24-hour heart rate variability (HRV) have been able to predict all-cause mortality after an acute myocardial infarction (AMI), but their value in predicting specific modes of cardiac death has been limited. AIM: The aim of this study was to assess the role of two novel spectral indexes of HRV as predictors of either sudden (SCD) or non-sudden cardiac death after an AMI. Method. We used two novel methods of spectral analysis of HRV: 1) the high-frequency (HF) spectral component, V(index), calculated as an average HF power from the most linear portion of HF power versus the R-R interval regression curve, and 2) the prevalent low-frequency oscillation of heart rate (PLF). V(index), conventional HRV measures, and PLF were analyzed from 24-hour Holter recordings of 590 patients with a recent AMI. RESULTS: During the mean follow-up of 39+/-14 months, SCD occurred in 3% (n = 17) and non-sudden cardiac death in 5% (n = 28) of the patients. In univariate analysis, V(index) was the most potent predictor of SCD (RR: 6.0, 95% CI: 1.7-20.7, P<0.01), also remaining the most powerful predictor of SCD after adjustment for clinical variables and ejection fraction (RR: 4.2, 95% CI: 1.2-15.2, P<0.05). PLF was a potent predictor of non-sudden cardiac death (RR: 13.9, 95% CI: 5.9-32.5, P<0.001), but it did not predict SCD. CONCLUSIONS: Novel spectral HRV analysis methods, V(index) and PLF, provide significant information of the risk of the specific mode of death after an AMI. 相似文献
48.
Taru Kantola Suvi Mklin Anna-Maria Koivusalo Pirjo Rsnen Anne Rissanen Risto Roine Harri Sintonen Krister Hckerstedt Helena Isoniemi 《World journal of gastroenterology : WJG》2010,16(18):2227-2234
AIM:To determine the short-term cost-utility of mo-lecular adsorbent recirculating system(MARS) treatment in acute liver failure(ALF).METHODS:A controlled retrospective study was conducted with 90 ALF patients treated with MARS from 2001 to 2005.Comparisons were made with a historical control group of 17 ALF patients treated from 2000 to 2001 in the same intensive care unit(ICU) specializing in liver diseases.The 3-year outcomes and number of liver transplantations were recorded.All direct liver disease-rel... 相似文献
49.
Renkonen S Häyry V Heikkilä P Leivo I Haglund C Mäkitie AA Hagström J 《Virchows Archiv : an international journal of pathology》2011,458(2):189-195
Juvenile nasopharyngeal angiofibroma (JNA) is a highly vascular tumour, occuring almost exclusively in adolescent males. Histogenesis
of JNA remains unclear, two optional theories proposing either fibrous or vascular tissue as the tissue of origin. Stem cell-related
proteins have been discussed to possibly participate in the growth of these tumours. In our study, we reviewed retrospective
clinicopathological data of 26 JNA patients. By immunohistochemistry, we investigated the cellular distribution and expression
levels of stem cell-related proteins C-KIT, C-MYC and BMI-1 and their correlation with cell and vessel density of the tumour.
Contrary to earlier reports, we detected C-KIT expression in addition to stromal cells also in endothelial cells. The C-KIT
expression was more dominant in slit vessels than large vessels. A significant correlation was found between endothelial immunoexpression
of C-KIT and cellular density of the tumour. C-MYC and BMI-1 expression was detected in stromal cells only. Due to our finding
of C-KIT expression in both stromal and endothelial cells and the strong correlation between the endothelial C-KIT expression
and cellular density, we suggest that, besides the stromal tissue, the vascular component might take part in the neoplastic
growth of JNA. 相似文献
50.
Rovio S Kåreholt I Viitanen M Winblad B Tuomilehto J Soininen H Nissinen A Kivipelto M 《International journal of geriatric psychiatry》2007,22(9):874-882
BACKGROUND: Leisure-time physical activity has been related with a reduced risk of dementia and Alzheimer's disease (AD). The effects of occupational and commuting physical activity (physical activity at work and on the way to work) on cognitive health are still unclear. This study aimed to clarify the association between work-related physical activity and dementia/AD. METHODS: Participants of the Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) study were derived from random, population-based samples previously studied in a survey carried out in 1972, 1977, 1982, or 1987. After an average follow-up of 21 years, 1449 individuals (73%) aged 65 to 79 years participated in the re-examination in 1998. RESULTS: Neither occupational [Odds Ratio (OR) 1.45; 95% Confidence Intervals (CI) 0.66-3.17] nor commuting physical activity (OR 0.46; 95% CI 0.10-2.17) were associated with the risk of dementia or AD after adjustments for age, sex, education, follow-up time, locomotor symptoms, main occupation during life, income at midlife, leisure-time physical activity, other subtype of work-related physical activity, ApoE genotype, vascular disorders and the smoking status. There were also no interactions between work-related physical activity and the ApoE epsilon4 genotype, leisure-time physical activity or sex. CONCLUSIONS: In this study, work-related physical activity was not found to be sufficient to protect against dementia and AD later in life. The lack of effect might be partly due to a residual confounding. Nevertheless, physical activity during leisure-time may be beneficial even for people who are physically active at work or when commuting. 相似文献