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111.
Tenascin, a novel extracellular matrix protein, was demonstrated immunohistochemically in rabbit corneas that had healed after anterior keratectomy. Tenascin-like immunofluorescence (T-LI) appeared in the corneal stroma at the wound area only. The wound edge showed the most intense specific fluorescence. The corneal epithelium, in general, displayed a moderate T-LI. Wounding did not induce any change in epithelial T-LI or T-LI located in the stroma outside the wound. 相似文献
112.
E MacDonald M Scheinin H Scheinin R Virtanen 《The Journal of pharmacology and experimental therapeutics》1991,259(2):848-854
Medetomidine (MED) is a veterinary sedative whose mode of action is activation of alpha-2 adrenoceptors. Because the carbon atom which separates the two ring systems is methylated, there is a center of stereochemical asymmetry in the molecule. The resulting enantiomers, d-MED and l-MED have recently become available for study. The biological activity of MED, as is now demonstrated in rats in vivo, seems to reside almost exclusively in the d-MED form. Only at extremely high doses (e.g., 10 mg/kg) does l-MED exert any effects, interpreted as alpha-2 adrenoceptor antagonism. In contrast, doses of d-MED as low as 30 micrograms/kg cause sedation, hypothermia and induce neurochemical changes in norepinephrine and 5-hydroxytryptamine metabolism in brain characteristic of alpha-2-agonists (decreases in concentrations of biogenic amine metabolites, turnover and increases in concentration of parent amine). The most sensitive neurochemical indicator of the alpha-2-agonist action of d-MED was the concentration of unconjugated 3-methoxy-4-hydroxy-phenyethylene glycol in rat cerebral spinal fluid, doses of d-MED as low as 10 micrograms/kg caused a significant reduction in this norepinephrine metabolite. Simultaneous administration of the specific alpha-2 adrenoceptor antagonist, atipamezole (1 mg/kg), effectively inhibited the behavioral and most of the neurochemical actions of d-MED (100 micrograms/kg). It is concluded that the enantiomers of MED may be extremely useful in elucidating structure action relationships at alpha-2 adrenoceptors. 相似文献
113.
I Virtanen V P Lehto T Vartio 《International journal of cancer. Journal international du cancer》1987,39(3):361-366
Affinity of iodinated fibronectin (Fn) and its defined proteolytic fragments to electrophoretically separated polypeptides of normal and malignant cells was studied in an overlay assay. Cellular 125I-Fn and a major 125I-Fn fragment (Mr 120,000-140,000), containing the cell-binding site, revealed in fibroblasts Mr 170,000, Mr 140,000, and Mr 47,000 Fn-binding polypeptides of which the first two could also be found in the plasma membrane preparations. Binding of 125I-Fns to Mr 170,000 and Mr 140,000 polypeptides was inhibited by the synthetic peptide Arg-Gly-Asp-Ser and to all 3 polypeptides by Fns and Mr 120,000-140,000 fibronectin fragment. Both fibrosarcoma cells and SV40-virus-transformed fibroblasts appeared to lack the Mr 140,000 Fn-binding polypeptide. Binding was similar when Fn from normal fibroblasts or fibrosarcoma cells was used in the assay, while plasma 125I-Fn had weaker affinity towards the Mr 140,000 polypeptide. Instead, proteolytic Fn-fragments, lacking the cell binding site, did not bind to any proteins in the assay. Radioactive cell-surface labelling showed differences in the corresponding surface polypeptide profiles of normal and malignant cells. The results suggest that the failure of pericellular matrix deposition in malignant cells could be due to either defective surface exposition or defective binding property of the Fn-receptor-like polypeptides. 相似文献
114.
K Verkkala A J?rvinen K Virtanen T Pellinen P Keto U S Salminen P Ketonen R Luosto 《Annales chirurgiae et gynaecologiae》1989,78(4):282-286
Seventy-one patients undergoing reoperation for coronary artery disease were examined on average 2.5 years postoperatively. Operative mortality was 9.9% and late mortality 6.3%. 88% of the patients improved subjectively, and although only 7.8% were angina-free, 79.9% were in NYHA Class I or II. All patients who had been working before reoperation returned to work, and either patients who were on sick-leave before resumed their activities. A follow-up examination was performed in 21 patients with a follow-up time of more than three years. The mean peak work capacity did not change after reoperation and also the ST changes during the bicycle ergometer exercise test were the same after reoperation. The mean ejection fraction diminished from 54 +/- 15.5% to 44.7 +/- 15.2%. In thallium perfusion studies areas of hypoperfusion were observed in 14 cases (67%). Coronary angiograms showed 3.0 +/- 1.0 patent anastomoses at the follow-up examination; 76% of the anastomoses performed in the reoperations were patent. It can be concluded that although the objective results of repeat myocardial revascularisation in this material are not optimal, the subjective improvement of the patients was satisfactory, and in the majority of cases reoperation ensures an acceptable quality of life for years. 相似文献
115.
S. Z. Mohebbi J. I. Virtanen M. Vahid-Golpayegani M. M. Vehkalahti 《Community dentistry and oral epidemiology》2008,36(4):363-369
Abstract – Objectives: To investigate the impact of feeding habits and daytime sugar intake on the prevalence of early childhood caries in a population where prolonged breastfeeding is a norm. Methods: A cross‐sectional study was carried out at 18 of 102 public health centers in Tehran. During a 4‐day period at each center, between 20 and 35 children aged 1–3 years were enrolled, resulting in a sample of 504 children. In structured interviews, mothers were asked to give information about their child’s feeding habits, daytime sugar intake, and their family’s background. Sugar intake during the night was operationalized as separately calculated burdens of nighttime breastfeeding and bottle‐feeding. Clinical dental examinations followed the World Health Organization criteria. Data analysis included chi‐square test, t‐test, anova , and logistic regression modeling. Results: Of the children, 56% were solely breastfed (mean duration 16.6 months; 95% CI 16.0–17.2), 42% were both breastfed and bottle‐fed, and 2% were solely bottle‐fed. Mean duration of breastfeeding for the solely breastfed 24‐ to 36‐month olds was 22.8 months (95% CI 21.8–23.9). At bedtime, 69% were breastfed, 11% bottle‐fed, and 20% were not fed at all. With respect to feeding during the night, 72% of children were breastfed, 12% were bottle‐fed with milk, 1% received a bottle with water, while 15% were not fed. Early childhood caries (ECC) occurred in 3–26% of the children, depending on age group (P < 0.001). The burden of milk‐bottle feeding at night was a clear determinant for ECC (OR = 5.5) whereas breastfeeding per se, its duration, the burden of breastfeeding at night, and daytime sugar intake were not. Conclusion: On account of its association with ECC, milk‐bottle feeding at night should be limited, whereas prolonged breastfeeding appears to have no such negative dental consequences. 相似文献
116.
Hyppönen E Virtanen SM Kenward MG Knip M Akerblom HK;Childhood Diabetes in Finland Study Group 《Diabetes care》2000,23(12):1755-1760
OBJECTIVE: The purpose of the present study was to evaluate the effect of obesity and linear growth on the risk of developing type 1 diabetes in children. RESEARCH DESIGN AND METHODS: The study population consists of all diabetic children <15 years of age diagnosed from September 1986 to April 1989 in Finland and their birth date- and sex-matched population-based control subjects. Growth data were obtained from well-baby clinics and school health care units for 586 diabetic and 571 control subjects, resulting in a total of 18,823 paired weight-height observations. RESULTS: Both boys and girls who developed type 1 diabetes were heavier and taller throughout childhood than control children. A 10% unit increment in relative weight was associated with a 50-60% increase in the risk of type 1 diabetes before 3 years of age and a 20-40% increase from 3 to 10 years of age. The increase in risk of type 1 diabetes for 1 SD score increment in relative height was 20-30%. Obesity (relative weight > 120%) after 3 years of age was associated with a more than twofold risk of developing type 1 diabetes. CONCLUSIONS: The present observation that obesity and rapid linear growth are risk factors for type 1 diabetes in children indicates that the increase in the prevalence of obesity and secular growth that has occurred in most industrialized countries over the last decades may be involved in the increase in type 1 diabetes incidence simultaneously observed in many countries. 相似文献
117.
Virtanen M Kähönen M Nieminen T Karjalainen P Tarvainen M Lehtimäki T Lehtinen R Nikus K Kööbi T Niemi M Niemelä K Turjanmaa V Malmivuo J Viik J 《Physiological measurement》2007,28(10):1189-1200
The diagnostic performance of heart rate variability (HRV) analysis from exercise ECG in the detection of coronary artery disease (CAD) is unknown. Bicycle exercise ECG recordings from The Finnish Cardiovascular Study (FINCAVAS) of angiography-proofed CAD patients (n = 112) and a patient group with a low likelihood of CAD (n = 114) were analyzed. HRV parameters (SDNN, RMSSD, Poincaré SD1 and SD2) were calculated from 1 min segments before exercise, during exercise and after exercise. All the parameters were in addition calculated from heart rate (HR)-corrected RR-interval segments. The ST-segment depressions in each stage were also determined. The diagnostic performance of the parameters was evaluated with the area under the receiver operating characteristic (ROC) curve method. The uncorrected HRV parameters showed the best diagnostic performance in the recovery segments but the correlation with HR was also high (SDNN: 0.758/-0.64, RMSSD: 0.747/-0.60; area under the ROC/correlation coefficient). The HR correction decreased the correlation and the diagnostic performance in recovery segments (SDNN: 0.515/-0.12, RMSSD: 0.609/0.20). The diagnostic performance of ST-level at its best was higher than any of HRV parameters (ST-level: 0.795/0.36). According to the results, the HR correction decreased the diagnostic performance of the recovery phase. The HRV parameters calculated from 1 min segments of exercise test ECG were not as capable as traditional ST-segment analysis. In conclusion, the HRV analysis from exercise or recovery phase seems to be inadequate in the detection of CAD. 相似文献
118.
M Hakama U Joutsenlahti A Virtanen U R?s?nen-Virtanen 《Annals of clinical research》1975,7(2):101-111
In Finland, up to 100,000 smears are taken annually from Finnish women, who number more than 2 millions, in conjunction with the mass screening programme organized by the Cancer Society of Finland. About 400,000 smears were taken during the period 1963-71; the detection rates per 10(5) were found to be 69 for invasive cancer, 6 for microinvasive carcinoma, 168 for carcinoma in situ, 127 for dysplasia of high degree. Those previously married, and those experiencing bleeding on sexual intercourse, formed high risk groups (relative risk 2 and 6) whereas those previously electro-coagulated had a relative risk of 0.13 only. Probably no changes will occur in the time trends of mortality rates as a result of the screening. The incidence of invasive carcinomas was found to be decreasing by time, although the increase in carconoma in situ cases exceeded this decline. 相似文献
119.
120.
Trimethoprim resistance of Escherichia coli in outpatients in Finland after ten years' use of plain trimethoprim 总被引:3,自引:0,他引:3
P Huovinen O V Renkonen L Pulkkinen R Sunila P Gr?nroos M L Klossner S Virtanen P Toivanen 《The Journal of antimicrobial chemotherapy》1985,16(4):435-441
Development of trimethoprim resistance among Escherichia coli collected from urine samples in three areas in Finland was studied in 1978-1984. Three different trends of development of resistance were found: in the Turku area resistance has increased evenly during 1978-1982 from 5.4% to 10.1%, but thereafter a plateau seems to have been reached; in the Helsinki area resistance increased rapidly from 2.9% in 1980 to 11.1% in 1984, possibly due to the spread of a trimethoprim resistance transposon Tn7, which occurred significantly more often among E. coli strains in this area than in the Turku area; in the Rovaniemi area resistance has been at a plateau level, between 3.1 and 5.7%, during the whole study. No clear correlation between the consumption of trimethoprim and the level of resistance was found. The frequency of trimethoprim resistance in E. coli isolated from patients less than 65 years was 5.2% and in those isolated from patients greater than or equal to 65 years 14.7%. 相似文献