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Noise of such a high level that it can result in hearing deterioration is an inherent characteristic of military flying. Susceptibility to hearing impairment was studied using 51 Finnish Air Force military personnel as subjects. The test persons flew missions on a British Aerospace Hawk 51 advanced jet trainer, Boeing F-18 Hornet, Mikoyan & Gurevich MiG-21bis and Saab 35 Draken interceptors, and a Valmet Redigo turboprop liaison aircraft. The duration of noise exposure was one flight mission, which varied from 30 to 60 min. Noise doses and levels were measured using a miniature microphone at the inlet of the ear canal, while a second microphone was located at the level of the subject's shoulder. Hearing thresholds were measured before each flight using conventional (0.125-8 kHz) and extended high-frequency (EHF) (8.20 kHz) audiometry. The measurements were repeated as soon as possible after the flight. The study showed that the pre-flight threshold levels of the subjects were good. Both conventional and EHF audiometry revealed statistically significant temporary threshold shifts (TTS) at several frequencies and with all aircraft types involved. The changes were, however, minor. The risk of noise-induced hearing impairment at the studied exposure levels is, in all probability, rather small. The role of extended high-frequency audiometry would be in research, and it might be performed for flying personnel upon entering service and every fifth year thereafter. 相似文献
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Laasanen J Hiltunen M Romppanen EL Punnonen K Mannermaa A Heinonen S 《European journal of human genetics : EJHG》2003,11(3):232-236
The pathophysiology of preeclampsia is incompletely understood, but the familial nature of the disease has long been recognized. Recent genome-scan studies have indicated linkage at the p23 region of chromosome 2. We have previously reported microsatellite marker association at chromosome region 2p13 in patients with obstetric cholestasis. We conducted population-based association screening with microsatellite markers to find potential preeclampsia-associated loci on chromosome region 2p13-p12 and to test whether preeclampsia and obstetric cholestasis share a single risk locus. The study was carried out among 115 unrelated control women, 133 preeclamptic women and 57 cholestatic women. Screening with microsatellite markers at the 2p13-p12 region revealed that the marker D2S286 was significantly associated with obstetric cholestasis in the overall association analysis (P=0.03), while it revealed only borderline association with preeclampsia (P=0.08). However, single allele association analysis indicated that both preeclampsia and obstetric cholestasis showed a statistically significant association with a common allele (P < 0.05), which was overrepresented in both the obstetric cholestasis (0.42) and preeclamptic (0.37) groups when compared with the control group (0.28). In conclusion, These findings suggest a possible genetic link between chromosome region 2p13-p12, preeclampsia and obstetric cholestasis. More specifically, these data suggest that there may be a common risk locus associated with both obstetric complications located in the vicinity of the 2p13-p12 association region. 相似文献
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Ezrin immunoreactivity in relation to survival in serous ovarian carcinoma patients 总被引:27,自引:0,他引:27
OBJECTIVE: Ezrin is a membrane-cytoskeleton linker protein, which regulates cell polarity and signaling. Increased ezrin expression in astrocytomas and uveal melanomas is correlated with unfavorable prognostic factors and reduced patient survival. We investigated ezrin IR in normal ovarian surface epithelium and serous ovarian carcinomas, and its relation with clinical parameters and patient outcome. METHODS: Tissue microarray blocks were constructed of all serous ovarian carcinoma tissue samples removed at a primary operation in Helsinki University Central Hospital between 1964 and 1999 and of healthy ovarian tissue samples. Ezrin expression was assessed by indirect immunohistochemistry using a monoclonal 3C12 ezrin antibody. Tissue samples (n = 440) were scored for the intensity of ezrin immunoreactivity, and the scores were compared with patient age, the stage and grade of disease, and disease outcome. RESULTS: Healthy ovarian epithelium showed strong polarized ezrin immunoreactivity. In serous ovarian carcinoma, the reactivity varied from strong (15.0% of samples) to moderate (57.3%) or weak/negative (27.7%) and the subcellular distribution was typically diffuse. Weak or negative expression of ezrin was associated with shorter survival (P = 0.027) but also with an advanced age of the patients (P = 0.0001), and a higher histological grade of the disease (P = 0.032). In Cox multivariate survival analysis, ezrin immunoreactivity had no independent effect on survival, when controlling for the stage and grade of the disease, and patient age. CONCLUSIONS: In contrast with astrocytomas and uveal melanomas, negative or weak ezrin immunoreactivity in serous ovarian carcinoma correlates with poor patient outcome. 相似文献
66.
Laasanen J Hiltunen M Punnonen K Mannermaa A Heinonen S 《Obstetrics and gynecology》2002,100(2):317-320
OBJECTIVE: To determine whether genetic variability in the promoter regions of the genes encoding fibrinogen and factor VII contribute to individual differences in susceptibility to the development of preeclampsia. METHODS: The study involved 133 preeclamptic and 115 healthy control pregnant women who were genotyped for the G-455A polymorphism in the beta-fibrinogen gene promoter and for a decamer insertion or deletion polymorphism at position -323 in the factor VII gene promoter. We used chi(2) analysis to assess genotype frequency differences between preeclamptic women and controls. RESULTS: The allelic distribution of the fibrinogen A-455G polymorphism was similar in the two groups, with the frequency of the variant A allele being 18.8% in the preeclampsia group and 20.9% in the control group. We did not find any association between the presence of the factor VII insertion allele and preeclampsia (5.6% versus 6.1%). Accordingly, the genotype distribution of the fibrinogen G-455A and factor VII polymorphisms in the preeclamptic and control groups was similar (P =.852 and P =.308). CONCLUSION: The G-455A polymorphism of the fibrinogen gene promoter and the decamer insertion or deletion polymorphism of the factor VII gene promoter are unlikely to be major genetic predisposing factors for preeclampsia in subjects from eastern Finland. 相似文献
67.
Svedström-Oristo AL Pietilä T Pietilä I Helenius H Peutzfeldt P Varrela J 《Acta odontologica Scandinavica》2002,60(3):160-166
There is no general agreement on criteria that could be applied to distinguish between orthodontically acceptable and non-acceptable occlusions after the completion of dental development. The aim of the present study was to analyse morphological and functional features that could be used as an index to define an acceptable occlusion in young adults. Three expert panels representing specialists in orthodontics and stomatognathic physiology participated in a modified Delphi method. Each panel responded to a questionnaire concerning the usefulness of various occlusal features, and a set of characteristics was selected on the basis of the responses; thereafter, applicability of the chosen characteristics and their cut-offs for an acceptable non-acceptable dichotomy was tested clinically. To obtain a consensus level of 100%, the last panel session was completed with a group discussion. Assessments made using the morphological criteria were compared with those made with the dental health component of the Index of Orthodontic Treatment Need. The selected morphological characteristics consisted of overjet, overbite, canine relationship, crossbite, scissors bite and midline deviation. The functional evaluation comprised assessments of discrepancy between the centric relation and the intercuspal position, working- and non-working-side contacts and protrusion contacts. The dental health component and our morphological criteria showed different sensitivity to contact point displacements, interdigitation in buccal segments and increased overbite. This study provides a set of morphological and functional indicators reflecting the current consensus opinion of Finnish professionals. Further studies are needed to analyse the reproducibility of assessment of the characteristics included. 相似文献
68.
Lavonius E Kerosuo E Kervanto-Seppälä S Halttunen N Vilkuna T Pietilä I 《Acta odontologica Scandinavica》2002,60(3):174-179
The objective of the study was to examine the coverage of the sealing program on first permanent molars (FPMs) and second permanent molars (SPMs) and first and second premolars (FSPMs), as well as to monitor the fate of the sealed teeth over time. All patients born in 1977 who had had regular check-ups in the Varkaus Health Center, Finland (n = 166) were included in the 1996 study. Data on the annual state of each tooth had been collected retrospectively since 1983. The coverage for the sealant program was 95%, 92%, and 6% of the FPMs, SPMs, and FSPMs, respectively. Out of the FPMs sealed at age 6 years, 28% were subjected to resealing, 13% developed occlusal, and 15% proximal caries during a 13-year follow-up period. From the SPMs sealed at age 11 years, 24% were subjected to resealing, 4% developed occlusal caries, and less than 2% proximal caries during the 9-year follow-up. None of the sealed FSPMs and only 1% of the non-sealed ones developed occlusal caries during the 9-year period. The mean DMF in the study population (n = 160) at age 12 years was 0.8 (n = 124), compared to a nation-wide mean value of 1.2. A large percentage of the FPMs and SPMs were sealed and then resealed during the study period. Although the study design lacked a control group for comparison, the lower caries rates of this study compared to the results of other studies with only a single application of sealants suggest a major role for resealing. 相似文献
69.
Nedeltchev K Arnold M Nirkko A Sturzenegger M Rihs F Bühler R Mattle HP 《Journal of clinical ultrasound : JCU》2002,30(3):132-138
PURPOSE: Transcranial Doppler sonography (TCD) is an established method for assessing changes in blood flow velocity (BFV) coupled to brain activity. Our objective was to investigate whether walking induces measurable changes in BFV in healthy subjects. METHODS: Changes in BFV in both middle cerebral arteries (MCAs) of 40 healthy adult subjects during walking on a treadmill were measured using bilateral TCD. In 8 of the 40 subjects, 1 anterior cerebral artery (ACA) was monitored simultaneously with the contralateral MCA. The percentage increase in BFV (BFVI%) compared with the baseline velocity (V(0)), the percentage decrease in BFV (BFVD%) compared with the V(0), and the normalized ACA-MCA ratio were analyzed. RESULTS: The overall mean (+/- standard deviation [SD]) V(0) was 59.9 +/- 11.6 cm/second in the left MCA and 60.1 +/- 12.9 cm/second in the right MCA. Women had higher V(0) values than men had. Walking evoked an initial mean overall BFVI% in both left (8.4 +/- 5.1%) and right MCAs (9.1 +/- 5.1%), followed by a decrease to below baseline values in 38 of 40 subjects. A statistically significant increase of the normalized ACA-MCA ratio was measured, indicating that changes in BFV in the ACA territory were coupled to brain activation during walking. CONCLUSIONS: The use of functional TCD showed different changes in BFV in the ACAs and MCAs during walking. This method may be an interesting tool for monitoring progress in patients with motor deficits of the legs, such as paresis. 相似文献
70.