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The aim of the present study was to investigate the long-term incidence rate of Lyme borreliosis and, additionally, to determine whether a correlation exists between climatic factors and summer-season variations in the incidence of Lyme borreliosis. Climatic variability acts directly on tick population dynamics and indirectly on human exposure to Lyme borreliosis spirochetes. In this study, conducted in primary healthcare clinics in southeastern Sweden, electronic patient records from 1997–2003 were searched for those that fulfilled the criteria for erythema migrans. Using a multilevel Poisson regression model, the influence of various climatic factors on the summer-season variations in the incidence of erythema migrans were studied. The mean annual incidence rate was 464 cases of erythema migrans per 100,000 inhabitants. The incidence was significantly higher in women than in men, 505 and 423 cases per 100,000 inhabitants, respectively (p<0.001). The summer-season variations in the erythema migrans incidence rate correlated with the monthly mean summer temperatures (incidence rate ratio 1.12; p<0.001), the number of winter days with temperatures below 0°C (incidence rate ratio 0.97; p<0.001), the monthly mean summer precipitation (incidence rate ratio 0.92; p<0.05), and the number of summer days with relative humidity above 86% (incidence rate ratio 1.04; p<0.05). In conclusion, Lyme borreliosis is highly endemic in southeastern Sweden. The climate in this area, which is favourable not only for human tick exposure but also for the abundance of host-seeking ticks, influences the summer-season variations in the incidence of Lyme borreliosis.  相似文献   
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OBJECTIVE To determine the long-term results of above-knee femoro-popliteal bypass with autologous saphenous vein (SV) or expanded polytetrafluoroethylene (ePTFE) in routine surgical practice. METHODS: Data from the Swedish vascular registry, Swedvasc, was reviewed retrospectively. Patients with bypass surgery in 1996 and 1997 were assessed 5-7 years later. Data were gathered from the case-records and from clinical follow-up. The composite endpoint of graft failure included death within 30 days, occlusion, major amputation, extension of the graft to below-knee position and removal of an infected graft. Kaplan-Meier curves and Cox' proportional hazard ratios were calculated. RESULTS: Four hundred and ninety-nine patients undergoing bypass for critical limb ischemia (CLI) (56%) or claudication (44%), SV (28%) or ePTFE (72%), were included. There were no significant differences in patient characteristics between patients with SV or ePTFE. CLI and ePTFE were risk factors for graft failure. For patients with both claudication and CLI SV grafts yielded better long-term results than ePTFE grafts ( p <0.03) and ( p <0.003), respectively. Symptom aggravation after graft occlusion was almost exclusively restricted to ePTFE grafts. CONCLUSIONS: Femoro-popliteal bypass above-knee with SV gives good long-term results, especially for claudication. ePTFE grafts cannot be recommended in claudicants, since occlusion occurs often and frequently leads to CLI.  相似文献   
5.
The aerobic faecal flora of 953 infants aged over 5 days was studied on discharge from 22 neonatal wards in Swedish hospitals. Klebsiella/enterobacter was isolated from 74% of infants and dominated the aerobic gram-negative flora in 19 wards. Escherichia coli was carried by 42% and showed a slight dominance in two wards. Initially klebsiella/enterobacter dominated the flora but became increasingly mixed with and taken over by E. coli, carriage increasing from 21% in infants discharged after 5-7 days to 57% after 3 weeks or later. Among infants with E. coli, P-fimbriated strains were demonstrated in 23% (range 0-67) and were independent of age. Occasional clustering of such strains was observed in 3/22 wards during the study period. It is postulated that the general and local colonization patterns observed reflect differences between individual strains of E. coli and klebsiella in both their capacity for transmission and their persistence in the newborn gut. The role of P-fimbriae in intestinal colonization of neonates by E. coli was, however, not supported.  相似文献   
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Plasma autoantibodies (aAbs) against the oxidized DNA base derivative 5-hydroxymethyl-2'-deoxyuridine (5-HMdU) are potential biomarkers of cancer risk and oxidative stress. We examined their association with a number of cancer risk factors: smoking, alcohol habits, body fatness, and absence of the glutathione S-transferases M1 and T1 (GSTM1 and GSTT1) in a sample from the population-based Malm? Diet and Cancer cohort (Sweden). This was a cross-sectional study of 264 men and 280 women, 46-67 years of age. Anti-5-HMdU aAb concentration was determined by an ELISA. Data on tobacco exposure were collected through a questionnaire. Alcohol consumption was estimated by a modified diet history method. Body fatness was assessed by a bioimpedance method. The absence or presence of genes coding for GSTM1 and GSTT1 was determined in granulocyte DNA by a multiplex PCR technique. aAb titers were significantly greater in those with high alcohol consumption. Current smokers lacking GSTM1, particularly men, had greater aAb titers compared with nonsmokers or persons expressing GSTM1. Body fatness was inversely associated with antibody titers in men. GSTT1 genotype was not associated with aAb titers. Overall, women had higher aAb titers than men. Adjustment for potential confounders (history of chronic diseases, anti-inflammatory medication, and season of blood sampling) did not change the results. Our study shows that a high alcohol consumption, smoking in combination with lack of GSTM1, and low body fatness (in men) is associated with high titers of anti-5-HMdU aAbs in this population.  相似文献   
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Background. Variation at the apolipoprotein E (apo E) locus influence lipid and lipoprotein levels in the normal population, and is associated with premature coronary artery disease. Patients with end-stage kidney disease or undergoing dialysis treatment are particularly prone to develop accelerated atherosclerosis. Methods. To evaluate the influence of genetic variation at the apo E locus, apo E genotypes and serum lipid and lipoprotein levels were measured in 51 subjects undergoing continuous ambulatory peritoneal dialysis (CAPD). Results. The distribution of apo E phenotypes and apo E allelic frequency among the CAPD subjects (&egr;2 0.049; &egr;3 0.745; &egr;4 0.206) corresponded to the healthy Swedish population. In the CAPD subjects, total serum and LDL cholesterol levels were high (6.7±1.5 mmol/l and 4.2±1.3 mmol/l respectively) and HDL cholesterol levels were low (1.2±0.5 mmol/l). When directly comparing the two major apo E groups, E 3/3 subjects (n=30) and E4/3 and 4/4 subjects, &egr;4-carriers, (n=16), LDL cholesterol levels were significantly higher among &egr;4-carriers (4,8±1.1 vs 4.0±1.2 mmol/l, P<0.03), but total serum cholesterol levels was not higher among the &egr;4-carriers (7.3±1.3 vs 6.5±1.5 mmol/l, P<0.08). Serum triglycerides or HDL cholesterol levels did not differ significantly between &agr;3-homozygotes and &egr;4-carriers. Conclusions. The results demonstrate a strong effect of variation of the apo E locus on LDL cholesterol levels in CAPD subjects, suggesting that &egr;4-carriers may be more susceptible to accelerated development of atherosclerosis in this condition.  相似文献   
8.
Mother's education and perinatal problems in Finland.   总被引:5,自引:0,他引:5  
This study using nationwide data expands a previous study from one area in Finland. The purpose was to study how perinatal problems (mortality, short gestation, low birthweight and low Apgar scores) vary by mother's social class, which is measured by level of education. Outcomes of all births in the 1987 Medical Birth Register were linked to the 1988 National Education Register with gives the estimated number of years of completed education. In unadjusted analyses, the lowest educational groups (less than 9 years) had the worst results for outcomes other than neonatal mortality. Results in the two highest educational groups (greater than or equal to 13 and 12 years of education) were similar and if anything, better in the second highest group. Excluding twins and adjusting for confounding variables (age, parity, county, urbanization of residence) by logistic regression analysis did not alter the results much. Adjustment for possible mechanisms correlated with social class (marital status, smoking, time of first antenatal visit) decreased the higher occurrence of low birthweight infants in the low educational groups. Reported previous miscarriages were more common in the higher educational groups. Based on the available background characteristics one would expect to have found the usual social gradient in perinatal problems to have persisted between the two highest educational groups. Further studies on factors causing the plateau in the gradient between these groups might be useful.  相似文献   
9.
The effect of exposure to organic solvents on uptake and metabolism of 5-HT was studied in rat lung slices. It was found that under control conditions 5-HT was both taken up and metabolized to 5-HIAA. When halothane (35,000 ppm) or trichloroethylene (18,000 ppm) were equilibrated with the incubation medium the uptake of 5-HT decreased by approximately 50% after 30 min of incubation, and the production of 5-HIAA was inhibited by approximately 70% and 80%, respectively. The results are consistent with earlier studies using a much more elaborate technique, in which halothane and trichloroethylene were found to depress 5-HT uptake in isolated perfused rat lungs. Our results demonstrate that the simpler technique employing lung slices can also be used, to investigate factors affecting pulmonary uptake of endogenous amines, and, potentially, the uptake of other compounds as well.  相似文献   
10.
PURPOSE: The purpose of this study was to determine the optimal concentration and volumes of ropivacaine for dental anesthesia as regards onset and duration of action. SUBJECTS AND METHODS: Thirty healthy individuals with a mean age of 32 years participated in the study on a voluntary basis. All subjects received a ropivacaine injection in 1 of 3 randomized concentrations (2.0, 5.0, or 7.5 mg/mL) for infiltration anesthesia and mandibular nerve block in a double-blind manner. The onset time and duration of anesthesia were assessed by electric pulp test, pinprick test of the gingiva, and presence of feeling of numbness of the lip. RESULTS: Regardless of dose, only 5 patients received pulpal anesthesia after infiltration, but all 3 concentrations anesthetized the gingiva and upper lip. The onset of pulpal anesthesia occurred less than 5 minutes after injection and lasted for 4 to 58 minutes. Pinprick anesthesia lasted for 8 to 48 minutes, and numbness of the upper lip lasted 1 to 4 hours. The effectiveness of the mandibular nerve block with regard to pulpal anesthesia was dose dependent. Only ropivacaine at 7.5 mg/mL produced sufficient anesthesia. The onset of pulpal anesthesia occurred less than 10 minutes after injection and lasted for 2 to 6 hours. Pinprick anesthesia lasted for 3 to 6 hours and numbness of the lower lip lasted for 5 to 9 hours. CONCLUSION: This study shows that ropivacaine could be useful as a local anesthetic for mandibular nerve block in dentistry and that the very long duration of both pulpal and soft tissue anesthesia may be favorable in reducing postoperative pain.  相似文献   
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