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51.
52.
Low incidence of acute urinary retention in the general male population: the triumph project 总被引:1,自引:0,他引:1
Verhamme KM Dieleman JP van Wijk MA Bosch JL Stricker BH Sturkenboom MC 《European urology》2005,47(4):494-498
OBJECTIVE: To describe the incidence of acute urinary retention (AUR) in the general male population and in a population of men newly diagnosed with lower urinary tract symptoms suggestive of BPH (LUTS/BPH). METHODS: We performed a retrospective cohort study in the Integrated Primary Care Information (IPCI) database, a GP research database in The Netherlands, during the period 1995-2000. All males, > or =45 years, without a history of AUR or radical cystectomy were included in the study. In addition, we followed a sub-cohort of men, newly diagnosed with LUTS/BPH. AUR was defined as the sudden inability to urinate, requiring catheterization. RESULTS: Amongst 56,958 males with a mean follow-up of 2.8 years, 344 AUR cases occurred (incidence rate 2.2/1000 man-years) of whom more than 40% were precipitated. AUR was the first symptom of LUTS/BPH in 73 (49%) of the 149 AUR cases that occurred in men newly diagnosed with LUTS/BPH. The risk of AUR was 11-fold higher in patients newly diagnosed with LUTS/BPH (RR 11.5; 95%CI: 8.4-15.6) with an overall incidence rate of 18.3/1000 man-years (95%CI: 14.5-22.8). CONCLUSIONS: The incidence rate of AUR is low in the general population but substantial in a population of men newly diagnosed with LUTS/BPH. The incidence rate increases with age and AUR is precipitated in approximately 40% of all cases. Within the LUTS/BPH cohort, AUR is the first presenting symptom of BPH in 50% of all AUR cases. 相似文献
53.
Glomerular number and function are influenced by spontaneous and induced low birth weight in rats 总被引:3,自引:0,他引:3
Schreuder MF Nyengaard JR Fodor M van Wijk JA Delemarre-van de Waal HA 《Journal of the American Society of Nephrology : JASN》2005,16(10):2913-2919
A link exists between low birth weight and diseases in adulthood, such as hypertension, cardiovascular disease, and insulin resistance. Intrauterine growth restriction (IUGR) has been used to explain this association and has been shown to lead to a nephron endowment in humans. A reduction in glomerular number has been described in animal models with induced low birth weight as well but not in animals with spontaneous low birth weight. It therefore is debatable whether the models are suitable. The effect on glomerular number and size was studied in rats with naturally occurring IUGR and experimental IUGR, induced by bilateral uterine artery ligation. Design-based stereologic methods were used. Urinary protein excretion was determined as a measure of renal damage. Results showed a decrease of approximately 20% in glomerular number in both groups of IUGR (control 35,400, naturally occurring IUGR 30,900, and experimental IUGR 28,000 glomeruli per kidney). Mean glomerular volume was increased in both IUGR groups, which was associated with an increased proteinuria. It is concluded that IUGR leads to a nephron endowment with a compensatory glomerular enlargement. This compensation is associated with more proteinuria in the long run. Uterine artery ligation in the pregnant rat is a suitable model to study the effects of IUGR on the kidney. 相似文献
54.
Rosiglitazone improves postprandial triglyceride and free fatty acid metabolism in type 2 diabetes 总被引:13,自引:0,他引:13
OBJECTIVE: Increased postprandial lipemia is part of diabetic dyslipidemia and is associated with accelerated atherosclerosis. We investigated the effects of the peroxisome proliferator-activated receptor-gamma agonist rosiglitazone on postprandial lipemia in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: A randomized, 8-week, crossover, placebo-controlled, double-blind trial was performed in which rosiglitazone at 4 mg was administrated twice daily in 19 patients with type 2 diabetes. Standardized 6-h oral fat-loading tests were performed after each treatment period. Postprandial curves were calculated as the total area under the curve (AUC) and the incremental area under the curve (dAUC). RESULTS: Rosiglitazone did not change fasting plasma triglycerides compared with placebo (1.97 +/- 0.22 vs. 1.88 +/- 0.20 mmol/l, respectively) but decreased postprandial triglyceride levels, leading to significantly lower triglyceride dAUC (-37%, P < 0.05), without changing total triglyceride AUC. Significant postprandial triglyceride reductions in the chylomicron fraction (Svedberg flotation rate [Sf] >400) were achieved with rosiglitazone, which resulted in a significant lower triglyceride AUC (-22%) in this fraction. The postprandial triglyceride increase in VLDL1 (Sf 60-400) was also lower after rosiglitazone (-27%), but this did not result in a significant lower triglyceride AUC. In VLDL2 (Sf 20-60), there were no significant differences in triglyceride AUC and triglyceride dAUC between rosiglitazone and placebo. Rosiglitazone decreased free fatty acid (FFA) AUC (-12%) and FFA dAUC (-18%) compared with placebo. CONCLUSIONS: Rosiglitazone improves the metabolism of large triglyceride-rich lipoproteins and decreases postprandial FFA concentrations in type 2 diabetes. This may have clinical implications, as these effects may contribute to cardiovascular risk reduction. 相似文献
55.
Multispectral analysis of magnetic resonance images 总被引:1,自引:0,他引:1
Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study. 相似文献
56.
Lemmer ER Vessey CJ Gelderblom WC Shephard EG Van Schalkwyk DJ Van Wijk RA Marasas WF Kirsch RE Hall Pde L 《Carcinogenesis》2004,25(7):1257-1264
Fumonisin B1 (FB1) is a naturally occurring mycotoxin produced by Fusarium verticillioides. Dietary exposure to FB1 has been linked to human cancer in certain parts of the world, and treatment with FB1 causes oval cell proliferation and liver tumors in rats. To study the potential role of oval (liver progenitor) cells in the cellular pathogenesis of FB1-induced liver tumors, we gave male F344 rats prolonged treatment with FB1 for 25 weeks, followed by return to control diet until 50 weeks ('stop study'). The time course of FB1-induced liver lesions was followed by examination of serial liver biopsies at set time intervals and post-mortem liver tissue at the end of the study. The effects of different FB1 treatment regimens (5 versus 25 weeks), as well as the modulating effect of 2-acetylaminofluorene (2-AAF), on the kinetics of oval cell proliferation and development of liver tumors were compared. Prolonged treatment with FB1 in normal diet caused persistent oval cell proliferation and generation of both hepatic adenomas and cholangiofibromas (CFs). These liver lesions occurred in the setting of chronic toxic hepatitis and liver fibrosis/cirrhosis, similar to that seen in human hepatocarcinogenesis. Some adenomas and CFs were dysplastic, and one post-mortem liver contained a hepatocellular carcinoma. OV-6+ oval cells were noted in close relation to proliferative neoplastic liver lesions, and some of these lesions expressed OV-6, suggesting that all these cell types were derived from a common progenitor cell. 2-AAF enhanced the size of FB1-induced glutathione S-transferase pi+ hepatocellular lesions and the incidence of CFs in post-mortem liver specimens, but this was not statistically significant. In conclusion, this study supports the involvement of dietary FB1 in liver carcinogenesis in male F344 rats. Oval cells may be the source of both the hepatocellular and cholangiocellular tumors induced by prolonged treatment with FB1. 2-AAF appears to have an enhancing effect on FB1-induced liver tumors, presumably due to its potent inhibitory effects on hepatocyte regeneration. 相似文献
57.
Elevated C-reactive protein levels during first trimester of pregnancy are indicative of preeclampsia and intrauterine growth restriction 总被引:3,自引:0,他引:3
Tjoa ML van Vugt JM Go AT Blankenstein MA Oudejans CB van Wijk IJ 《Journal of reproductive immunology》2003,59(1):29-37
C-reactive protein (CRP) is a marker of tissue damage and inflammation. Maternal levels of CRP are elevated in overt preeclampsia, but there is still debate about its use as a predictive marker for preeclampsia during the first and second trimesters of pregnancy. In this study, we measured CRP levels during the first trimester of pregnancy in women who later developed preeclampsia or gave birth to a growth-restricted baby. In total, 107 women from a low-risk population participated in the study, six women developed preeclampsia and nine gave birth to a growth-restricted baby. Although there is a large overlap in measured CRP levels between the three groups, mean CRP levels were significantly elevated in women who later developed preeclampsia (P=0.031) or delivered a growth-restricted baby (P=0.041) when compared with women from the control group, matched for maternal and gestational age, parity, and gravidity. This study shows that in a low-risk population, CRP levels are already elevated between weeks 10 and 14 in pregnant women who develop preeclampsia or deliver a growth-restricted baby. 相似文献
58.
Normalization of daytime triglyceridemia by simvastatin in fasting normotriglyceridemic patients with premature coronary sclerosis 总被引:3,自引:0,他引:3
van Wijk JP Halkes CJ De Jaegere PP Plokker HW Erkelens DW Cabezas MC 《Atherosclerosis》2003,171(1):109-116
Postprandial hyperlipidemia is associated with premature coronary sclerosis in fasting normolipidemic subjects. Self-determined daytime capillary triglyceride (cTG) profiles were compared between 26 fasting normotriglyceridemic patients with premature coronary artery disease (CAD) and 26 controls matched for gender, age and BMI. Daytime triglyceridemia was calculated as total area under the cTG-curve (cTG-AUC). Total and LDL cholesterol were not different between CAD patients (5.4+/-0.8 mmol/l and 3.6+/-0.7 mmol/l, respectively) and controls (5.0+/-0.9 mmol/l and 3.3+/-0.8 mmol/l, respectively). Patients with CAD were characterized by a 44% higher cTG-AUC than matched controls (P<0.01). Using logistic regression analysis, cTG-AUC was the strongest predictor of the presence of CAD (P<0.001). Adding apo AI to the model improved the predictive power from 71 to 77%. Sixteen patients were studied after increasing doses of simvastatin up to 80 mg/day. Although the target for LDL cholesterol was reached by simvastatin 20mg/day, significant effects on cTG-AUC were found only by higher doses of simvastatin. Simvastatin 40 mg/day decreased cTG-AUC by 28% (P<0.05 versus baseline), reaching comparable values as in controls, without further improvement with simvastatin 80 mg/day (26% reduction versus baseline; P<0.05). Daytime triglyceridemia is linked to premature coronary sclerosis in fasting normotriglyceridemic patients. A higher dose of simvastatin was needed to normalize daytime triglyceridemia than was required to "normalize" LDL cholesterol. 相似文献
59.
OBJECTIVE: To determine changes over time in the ankle brachial index (ABI) among subjects with and without intermittent claudication in the general population. DESIGN OF STUDY: Population cohort study. SETTING: General population in Edinburgh, Scotland. SUBJECTS: A total of 1592 men and women aged 55 to 74 years selected at random from age-sex registers of 11 general practices and followed up over 12 years.Main outcome measures Changes in ABI for each leg recorded at baseline in 1988 and at subsequent 5-year and 12-year clinical examinations. RESULTS: Overall, 695 subjects (348 men and 347 women) had valid ABI measurements on both legs at all three examinations. At baseline, the ABI was on average.03 higher in the right leg than the left (P < or =.001). Men had a mean ABI that was.07 higher than women (P < or =.001). Mean ABI in the worse leg showed little change over 12 years in both men and women. However, in the whole population, the ABI in the better leg showed a significant drop, 1.15 to 1.08 (P < or =.001). A total of 179 cases of intermittent claudication were identified during the 12-year follow-up. At baseline, ABI in the worse leg of the claudicants was significantly lower than in healthy subjects (.99 vs 1.08; P < or =.01). In claudicants, mean ABI in the worse leg fell by.04 over 5 years (P < or =.05) and in the better leg showed a highly significant drop of.09 (P < or =.001) to levels similar to those of the worse leg. CONCLUSIONS: The mean ABI in the worse leg of study subjects showed little progression over 12 years. Individuals with intermittent claudication experienced a greater decline in both legs compared with those without claudication. Deterioration occurred more rapidly in the limb with a higher ABI at baseline, which possibly indicates a systemic tendency to atherosclerosis. 相似文献
60.
This study examined the effect of oral and product temperature on the perception of texture and flavor attributes. A trained panel assessed 21 texture and flavor attributes in one high-fat and one low-fat product of two semi-solids: custard dessert and mayonnaise. The products were evaluated at 10, 22 or 35 degrees C in combination with oral temperatures of 27, 35 and 43 degrees C. Results showed that modulation of product and oral temperature had significant effects on a number of attributes. Flavor intensities, melting mouth feel, and fat after feel increased, while subjective thickness decreased with increasing product temperature. Neither product- nor oral temperature had an effect on over-all creaminess. Oral temperature affected a number of mouth feel attributes: melting, heterogeneous and smooth. Furthermore, large differences existed in ratings between the high- and low-fat products of custard and mayonnaise, and they were more prominent in mayonnaise. We conclude that the effect of oral temperature on the perception of sensory attributes in semi-solids was small, but present, while the product temperatures influenced the ratings greatly. 相似文献