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排序方式: 共有1311条查询结果,搜索用时 31 毫秒
1.
J S Lindholt S Juul H Fasting E W Henneberg 《European journal of vascular and endovascular surgery》2006,32(1):9-15
BACKGROUND: The aim of this study was to estimate the cost effectiveness of screening for abdominal aortic aneurysm (AAA). MATERIAL AND METHODS: All 12,639 men born in the years 1921-1933 (aged 64-73) living in Viborg County, Denmark, were randomly allocated either to receive an invitation to abdominal ultrasound scanning for AAA or to be controls. Costs for screening and surveillance were assessed prospectively. Diagnosis Related Group (DRG) costs from 1999 were used concerning admissions with uncomplicated and complicated operations. Admissions for AAA surgery were retrospectively classified according to complications in patient records. RESULTS: Mean follow-up time was 52 months. 76.6% of invited men attended screening, and 191 (4.0%) had an AAA. As previously reported, the cumulative 5-year AAA-specific mortality in the invited group was significantly reduced by 67% compared to the control group (P = 0.003). The costs were estimated to be Euro 11.23 per scan. The costs per life-year saved were Euro 9057 (Euro 5872-20,063) after 5 years, and were expected to decrease to Euro 2708 (Euro 1758-6031) after 10 years and to Euro 1825 (Euro 1185-4063) after 15 years. CONCLUSION: Screening of 64-73 years old males in Denmark seems cost effective. 相似文献
2.
R. Juul L. Edvinsson T. A. Fredriksen R. Ekman A. O. Brubakk S. E. Gisvold 《Acta neurochirurgica》1990,107(3-4):75-81
Summary NPY is a putative neurotransmitter mainly co-localized with noradrenaline in sympathetic fibers which innervate the cerebral vasculature. The origin of most of the perivascular NPY fibers seems to be in the superior cervical ganglion. To investigate involvement of Neuropeptide Y (NPY) mechanisms in subarachnoid haemorrhage (SAH), twenty patients with SAH were investigated. NPY-LI (-like immunoreactivity) levels in the external jugular vein were assessed using radioimmunoassay in blood samples collected postoperatively (or after SAH in non-surgical patients) on days 1, 2, 3, 5, 7 and 9. These levels were compared with the clinical course and blood flow velocity changes monitored with ultrasonic Doppler equipment from both middle cerebral arteries (MCA) and both internal carotid arteries (ICA).Compared to NPY-LI levels in 14 controls (mean 116±3 pmol/ l), increased levels (up to 253 pmol/l) and a close relationship between velocities and NPY-LI levels were found in a subpopulation of the SAH patients. When comparing the mean haemodynamic index (V MCA/ipsilateral V ICA) and mean NPY-LI levels in each of the 20 patients, a correlation of r=0.75, p=0.0001 was found. Increased NPY-LI were found (131±8 pmol/l) when simultaneous Doppler velocity recordings showed vasoconstriction (Haemodynamic index >5) compared with samples taken when the haemodynamic index was <5, p<0.05. When MCA velocity exceeded 120 cm/sec, increased levels were found (129±9 pmol/l) compared with the conditions when MCA velocity was less than 120 cm/sec (113±5 pmol/ l), p=0.06. The results indicate a possible NPY involvement in cerebral vasoconstriction after SAH. 相似文献
3.
Possible relevance of pigeons as an indicator species for monitoring air pollution. 总被引:4,自引:1,他引:3
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P A Schilderman J A Hoogewerff F J van Schooten L M Maas E J Moonen B J van Os J H van Wijnen J C Kleinjans 《Environmental health perspectives》1997,105(3):322-330
Wild city pigeons were caught at four different locations in the Netherlands to represent areas of high (Amsterdam-high), moderate (Amsterdam-medium), and low (Maastricht and Assen) traffic density. It is assumed that local ambient air pollution decreases as a function of traffic density. In these pigeons levels of polycyclic aromatic hydrocarbon (PAH)-DNA adducts, oxidative DNA damage, and heavy metal residues were determined in kidney, lung, liver, and blood (no adduct analysis in blood). The contribution of leaded gasoline to total body lead content was estimated by measuring concentrations of Pb and its isotopes in blood. We also analyzed samples of ambient air particulate matter for PAH and heavy metal concentrations at the four different locations. Interregional differences in heavy metals in ambient air particulate matter were reflected relatively well by pigeon body loads. The higher lead and cadmium concentrations in blood, kidney, liver, and lung were found in the Amsterdam high traffic density area, followed by Amsterdam medium, Assen, and Maastricht. A high Pb concentration in blood coincided with relatively low 206Pb/207Pb values, indicating a high contribution of leaded gasoline to total blood Pb concentrations in pigeons from the Amsterdam high traffic density area. Significantly enhanced blood zinc values were found in pigeons from both locations in Amsterdam compared to pigeons from the other two areas. However, no differences in Zn tissue levels between the four different groups were found. Oxidative DNA damage, determined as the ratio of 7-Hydro-8-oxo-2'-deoxyguanosine/ deoxyguanosine, in pigeon liver was highest in Amsterdam-high, followed by Assen (low traffic density). Pb content, but not the Cd content, was positively associated with oxidative DNA damage in liver tissue. In lung tissue, a negative correlation was found between oxidative DNA damage and Zn content. These results indicate that the carcinogenic potential of Pb might be ascribed to oxygen radical formation, whereas Zn plays a protective role against oxidative DNA damage. Places with high and medium traffic density could be clearly discriminated on the basis of PAH levels in the ambient air. The PAH content in particulate air samples was not, however, reflected in total PAH-related DNA adduct levels because no differences could be observed in tissue adduct levels in pigeons from the four different locations. Our results indicate that wild city pigeons can be used as biological indicators of exposure to heavy metal pollution in outdoor air. 相似文献
4.
Dr. Peter Layer MD Jens Juul Holst Daniel Grandt Harald Goebell 《Digestive diseases and sciences》1995,40(5):1074-1082
There is evidence that the distal intestine participates in the regulation of gastric motor and secretory function. It was the aim of this study to examine in greater detail the effects of ileal nutrient exposure on human gastric acid secretion and to investigate potential intermediary mechanisms. Twelve normal subjects were intubated with an oroileal multilumen tube assembly for gastric, duodenal, and ileal perfusion of marker and test solutions, aspiration, and intestinal manometry. We studied ileal effects on gastric acid output in the unstimulated, interdigestive state (during early phase II,N=6), and during endogenous stimulation by intraduodenal essential amino acid perfusion,N=6) and on release of candidate humoral mediators, peptide YY (PYY) and glucagonlike peptide-1 (GLP-1), both known inhibitors of human gastric acid secretion. Compared with ileal saline perfusion, ileal carbohydrate (total caloric load: 60 kcal) decreased interdigestive gastric acid output by 64% (P<0.01), and endogenously stimulated output by 68%, respectively (P<0.005). Under all experimental conditions, ileal carbohydrate increased plasma GLP-1 by 80–100% (allP<0.005). Ileal lipid perfusion had similar inhibitory effects on gastric acid output and stimulatory effects on GLP-1 release as had ileal carbohydrate. By contrast, ileal perfusion with peptone had no or only weak effects on either acid output or plasma GLP-1. Plasma PYY concentrations and suppression of gastric secretion in response to ileal perfusions were not correlated. In humans, both interdigestive and endogenously stimulated gastric acid output are inhibited in response to intraileal carbohydrate or lipids, but not protein, Decreased acid output is associated with release of GLP-1, but not PYY. These findings support the hypothesis that the distal small intestine may participate in the late postprandial inhibitory regulation of gastric secretory function in humans and that GLP-1 may be an intermediary factor. 相似文献
5.
Henrik Christian Juul Nyholm Ib Jarle Christensen Anette Lynge Nielsen 《Gynecologic oncology》1995,59(3)
Estrogen receptor (ER) and progesterone receptor (PR) contents were determined by biochemical (dextran charcoal-coated (DCC) assay) and immunohistochemical (ICA) methods in biopsies from 145 primary endometrial adenocarcinomas and those with eligible receptor measurements were analyzed with respect to correlations to cancer-specific survival in a multivariate analysis including histopathological characteristics. Median patient follow-up time was 67 months with 18 cancer deaths. The PR-DCC and ER-DCC values were dichotomized according to levels previously found by us to correspond to the best agreement between receptor status as determined by the DCC and ICA methods (130 fmol/mg cytosol protein for ER, 114 fmol/mg for PR). Using these thresholds, we found by multivariate analysis that “high” PR-DCC levels (>114 fmol/mg) correlated significantly (P= 0.004) with survival, independent of stage risk group (Ia + b vs Ic-IV). Patient age and histologic grade were prognostic factors in a univariate setting, but these parameters were eliminated in the multivariate model. While the PR-ICA scores also correlated significantly and independently with survival, the predictive effect of PR-ICA positivity alone could not be statistically evaluated due to the number of cases with eligible ICA values. However, we suggest that owing to a close correlation between DCC and ICA results, PR-ICA status may provide significant prognostic information when DCC measurements are not available. 相似文献
6.
Summary Patients with post-concussional symptoms (PCS) about 6 months after a mild head injury (MHI) were examined for tolerance of light and sound in comparison with concussed patients without PCS and nonconcussed healthy controls. MHI patients with PCS were individually matched with subjects from the two control groups for the time elapsed from the injury, and for age and sex. Using a computerized rating technique, we assessed both the maximal and submaximal levels of lowered tolerance for light and sound over a wide range of stimuli. We found that the MHI patients with PCS 6 months after the trauma (n=11) tolerated significantly less well stimuli of intensities of 71 dB and 500 lx than MHI patients without PCS (n=11) and non-concussed controls (n=11). There were no significant differences in tolerance for light and sound between MHI patients without PCS and the non-injured controls. Decreased tolerance for light and sound may contribute to the persistence of symptoms up to 6 months after a mild head injury. The psychophysical method provides an objective measure for the evaluation of the late persistent postconcussional syndrome. 相似文献
7.
N Juul M Holm-Bentzen H Rygaard H H Holm 《Scandinavian journal of urology and nephrology》1987,21(2):135-137
To illucidate the diagnostic accuracy of ultrasound in the detection of renal stones we performed a blind comparative study of ultrasonography and i.v. urography. In 92 kidneys with 58 stones, 10 stones smaller than 6 mm were overlooked by ultrasound, whereas all stones 6 mm or larger were correctly detected. In one case of uric acid stone disease i.v. urography was inconclusive in determining the true nature of a renal pelvic filling defect, whereas ultrasound correctly diagnosed a stone. We conclude that ultrasonography has a place in diagnosis and control of renal stones. 相似文献
8.
R.M.H. Wijnen B.-G. Ericzon A.T.M.G. Tiebosch W.A. Buurman C.G. Groth G. Kootstra 《Transplant international》1992,5(Z1):S454-S458
We investigated clinical, biochemical, and histopathological parameters in FK506-treated cynomolgus monkeys. Eight monkeys given oral FK506, 1 (n = 4) or 10 (n = 4) mg/kg daily, survived the 90 days of treatment apparently in good health and without significant changes in biochemical and histopathological parameters, as did 2 control monkeys except one monkey on 10 mg/kg/day FK506 orally, who was found to have a malignant lymphoma. In contrast, monkeys given intramuscular FK506 1 mg/kg daily (n = 4) had to be sacrificed at day 20, 25, 32, and 47 because of severe illness. They showed abnormal biochemical parameters (increased serum urea and aspartate aminotransferase activity) and major histopathological changes in the kidney (mesangial cell proliferation and acute tubular necrosis), pancreas (depletion of beta cells), liver (steatosis), and heart (cardiomyopathy). Intramuscular administration of 1 mg/kg daily resulted in serum levels ranging from 10 to 15 ng/ml, while oral administration at a dose of 1 or 10 mg/kg daily resulted in equal or even higher serum levels (range 2–70 ng/ml). Thus, the height of the serum trough level of FK506 using the enzyme immunoassay is not related to the toxicity of FK506 in cynomolgus monkeys. 相似文献
9.
10.
In a prospective study intravenous urography (IVP) and abdominal ultrasonography (US) were compared in 100 consecutively admitted male patients with symptoms of infravesical obstruction. No pathology was found in 67 patients on IVP and in 61 patients on US. Both modalities disclosed 5 bilateral, 4 unilateral hydronephroses and one patient with contracted kidneys. IVP found 7 renal masses: one solid tumour, 2 "possibly solid" tumours and 4 "possibly cysts", whereas US found one solid tumour and 16 cysts. Both modalities detected 3 kidney stones, 5 bladder stones and 3 bladder tumours. It is concluded that "imaging" of the urinary tract is only indicated in cases of haematuria, elevated creatinine, history of renal calculous disease and other clinical suspicion of upper urinary tract disease. It is further concluded that US is preferable to IVP in this patient category due to (1) better characterization of renal masses, (2) the possibility of investigating the liver and the retroperitoneum in the same setting, (3) better evaluation of the prostate with respect to size, (4) better evaluation of the bladder, and (5) last but not least for economical reasons. However, bone metastases will be missed. 相似文献