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排序方式: 共有411条查询结果,搜索用时 6 毫秒
31.
Avendaño M Kunst AE van Lenthe F Bos V Costa G Valkonen T Cardano M Harding S Borgan JK Glickman M Reid A Mackenbach JP 《American journal of epidemiology》2005,161(1):52-61
This study assesses whether stroke mortality trends have been less favorable among lower than among higher socioeconomic groups. Longitudinal data on mortality by socioeconomic status were obtained for Finland, Norway, Denmark, Sweden, England/Wales, and Turin, Italy. Data covered the entire population or a representative sample. Stroke mortality rates were calculated for the period 1981-1995. Changes in stroke mortality rate ratios were analyzed using Poisson regression and compared with rate ratios in ischemic heat disease mortality. Trends in stroke mortality were generally as favorable among lower as among higher socioeconomic groups, such that socioeconomic disparities in stroke mortality persisted and remained of a similar magnitude in the 1990s as in the 1980s. In Norway, however, occupational disparities in stroke mortality significantly widened, and a nonsignificant increase was observed in some countries. In contrast, disparities in ischemic heart disease mortality widened throughout this period in most populations. Improvements in hypertension prevalence and treatment may have contributed to similar stroke mortality declines in all socioeconomic groups in most countries. Socioeconomic disparities in stroke mortality generally persisted and may have widened in some populations, which fact underlines the need to improve preventive and secondary care for stroke among the lower socioeconomic groups. 相似文献
32.
Painter JN Savander M Ropponen A Nupponen N Riikonen S Ylikorkala O Lehesjoki AE Aittomäki K 《European journal of human genetics : EJHG》2005,13(4):435-439
Intrahepatic cholestasis of pregnancy (ICP) is a cholestatic condition that may affect women during the third trimester of pregnancy. Symptoms experienced by these women generally resolve spontaneously following delivery, but prior to delivery the fetus is at increased risk of intrauterine distress and sudden intrauterine death. The genetic etiology of most cases of ICP is unknown, although heterozygous carriers of mutations causing progressive familial intrahepatic cholestasis (PFIC) diseases may experience ICP. When examining linkage to known cholestasis genes, affected members of four Finnish ICP families shared haplotypes around ATP8B1, the gene responsible for PFIC1. This gene was subsequently screened in 176 familial and sporadic ICP patients. A total of 17 sequence changes were detected, five exonic and 12 intronic. No intronic change was associated with ICP in sporadic cases. Four intronic changes segregated with ICP in three families, a different change in each of two families and three changes in another family, although the significance of this is currently unknown. Three exonic changes were nonsynonymous, one (in exon 23) is probably a polymorphism while two predict novel amino-acid replacements (N45T and K203R). These changes, in exons 2 and 7, were detected in one individual each, and may have predisposed these individuals to ICP. In conclusion, although the exon 2 and 7 changes may have functioned as risk alleles, ATP8B1 is probably not a major gene contributing to the occurrence of ICP. 相似文献
33.
A hydrophobic grid membrane filter-colony hybridization (HGMF-CH) method for the enumeration and isolation of cpe gene-carrying (cpe-positive) Clostridium perfringens spores from feces was developed. A 425-bp DNA probe specific for the cpe gene was sensitive and specific when tested with bacterial DNA and pure cultures. The enumeration of cpe-positive C. perfringens by the HGMF-CH method proved to be as sensitive as nested PCR combined with the most-probable number technique when tested with fecal samples from healthy individuals. With the aid of the HGMF-CH method, positive hybridization signals were detected from two out of seven fecal samples obtained from healthy individuals. Furthermore, cpe-positive C. perfringens was successfully isolated from both of these samples. The detection of cpe-positive C. perfringens by the HGMF-CH method is dependent on the ratio of cpe-positive C. perfringens colonies to total C. perfringens colonies growing on the HGMF-tryptose-sulfite-cycloserine plate. cpe-positive C. perfringens could be isolated if the ratio of cpe-positive C. perfringens spores to total C. perfringens spores was 6 x 10(-5) or higher. The HGMF-CH method provides an aid in the investigation of fecal samples of patients suffering from food poisoning or other diseases caused by cpe-positive C. perfringens. The method also offers a new approach in the investigation of the epidemiology of cpe-positive C. perfringens strains. 相似文献
34.
IsHak JA Kreuze JF Johansson A Mukasa SB Tairo F Abo El-Abbas FM Valkonen JP 《Archives of virology》2003,148(12):2449-2460
Summary.
Sweet potato feathery mottle virus (SPFMV, genus Potyvirus, family Potyviridae), Sweet potato chlorotic stunt virus (SPCSV, genus Crinivirus, family Closteroviridae) and sweet potato virus G (SPVG) were detected in naturally infected sweet potato plants grown in the Delta region in Egypt. Before this study, SPVG was reported only from China. Two isolates of SPFMV and one isolate of SPVG were characterized for the 3-proximal genomic sequences. Phylogenetic analyses indicated that the SPFMV isolates belong to the russet crack strain group (RC). Serological tests using monoclonal antibodies, and phylogenetic analysis of a partial sequence of the Hsp70 gene, indicated that the Egyptian SPCSV belongs to the so-called non-East African strain group of SPCSV.The two first authors contributed equally to this work. 相似文献
35.
Summary. The complete sequence of a new wheat-infecting isolate of Wheat dwarf virus from Sweden (WDV-[Enk1]) was determined, as well as a 726-nt region covering part of rep and the long intergenic region (LIR) of six other wheat-infecting Swedish isolates and a barley-infecting isolate from Hungary
(WDV-Bar[HU]). Analyses including these and previously published sequences showed that the wheat-infecting isolates of WDV
displayed less than 3% of divergence. Most of the nucleotide changes were silent and the largest variation was detected in
LIR. In contrast, the barley-infecting isolate was clearly different with 16% of sequence divergence compared to the wheat
isolates. The WDV isolates infecting barley or wheat seem to represent two differentiated strains.
April 23, 2001 August 27, 2001 相似文献
36.
Taylor A Angerer J Claeys F Kristiansen J Mazarrasa O Menditto A Patriarca M Pineau A Schoeters I Sykes C Valkonen S Weykamp C 《Clinical chemistry》2002,48(11):2000-2007
BACKGROUND: The different scoring methods used by eight European External Quality Assessment Schemes (EQASs) for occupational and environmental laboratory medicine were compared to develop suitable quality specifications as a step toward harmonization. METHODS: Real results for blood lead and serum aluminum assays, reported by participants in Italian and United Kingdom EQASs, were evaluated according to individual scheme scoring criteria. The same results were then used to produce z scores using scheme-based between-laboratory SDs as the estimate of variability to determine whether simple performance-derived quality specifications produced better agreement among schemes. RESULTS: The schemes gave conflicting assessments of participants' performance, and participants judged to be successful by one scheme could be defined as performing inadequately by another. An approach proposed by Kenny et al. (Scand J Clin Lab Invest 1999;59:585), which uses clinical inputs to set targets for analytical imprecision, bias, and total error allowable, was then used to elaborate quality specifications. CONCLUSIONS: We suggest that the CLIA '88 recommendations for blood lead (+/- 40 micro g/L or +/- 10% of the target concentration, whichever is the greater) could be used as a quality specification, although a revision to +/- 30 micro g/L or +/- 10% is recommended. For serum aluminum, a suitable quality specification of +/- 5 micro g/L or +/- 20% of the target concentration, whichever is the greater, is suggested. These specifications may be used to compare laboratory performance across schemes. 相似文献
37.
Miia Tiihonen Anna-Mari Heikkinen Hanna-Mari Lepp?nen Riitta Ahonen 《Pharmacy World & Science》2010,32(1):66-72
Objective The aim of this study was to examine information sources used by women who use hormonal contraceptives (HCs), and how information
source affected women’s attitudes and perceptions in 2001 and 2007. Setting The questionnaires were distributed from university pharmacies in 12 large cities across Finland. Method The data were collected with two questionnaire surveys among women who used hormonal contraceptives in 2001 and 2007. In
the 2001 survey the response rate was 53% (n = 264) and in the 2007 survey 55% (n = 436). Results The number of respondents who considered professional information sources the most important information sources was markedly
bigger in 2007 than in 2001 (P = 0.005). The most common source of information concerning the benefits of hormonal contraceptives was a physician (2001:
43%, 2007: 53%). The most common source of information concerning the risks of hormonal contraceptives was friends and relatives
(43%) in 2001 and physician in 2007 (35%). Only a few percent of the respondents considered a pharmacy the most important
information source both the 2001 and 2007 surveys. Conclusion The importance of health care professionals as sources of information concerning hormonal contraceptives has increased. However,
role of pharmacists as information source was surprisingly small. Women who use hormonal contraceptives need more information
from professional sources to alleviate possible fears associated with use. 相似文献
38.
A quality control program of analyses of toxic metals in urine has been carried out in the Nordic countries since 1978. In connection with these programs, the advantages and disadvantages of lyophilized compared to natural urine specimens as control materials have been investigated in three successive similar studies. Three parallel lyophilized and natural specimens were distributed to 12 participating laboratories. Two of the three specimen pools were spiked with known amounts of As, Cd, Cr, Hg, Ni, and Pb standard solutions. The data indicate no clear differences in the mean concentrations, coefficients of variation, or mean recoveries for the various metals between the two control materials used with the various types of analytes. However, rather wide random variations were observed, emphasizing the analytical difficulty of these analyses and the need for routine quality control. 相似文献
39.
K Pesola J Nenonen R Fenici J L?tj?nen M M?kij?rvi P Fenici P Korhonen K Lauerma M Valkonen L Toivonen T Katila 《Physics in medicine and biology》1999,44(10):2565-2578
The accuracy of localizing source currents within the human heart by non-invasive magneto- and electrocardiographic methods was investigated in 10 patients. A non-magnetic stimulation catheter inside the heart served as a reference current source. Biplane fluoroscopic imaging with lead ball markers was used to record the catheter position. Simultaneous multichannel magnetocardiographic (MCG) and body surface potential mapping (BSPM) recordings were performed during catheter pacing. Equivalent current dipole localizations were computed from MCG and BSPM data, employing standard and patient-specific boundary element torso models. Using individual models with the lungs included, the average MCG localization error was 7+/-3 mm, whereas the average BSPM localization error was 25+/-4 mm. In the simplified case of a single homogeneous standard torso model, an average error of 9+/-3 mm was obtained from MCG recordings. The MCG localization accuracies obtained in this study imply that the capability of multichannel MCG to locate dipolar sources is sufficient for clinical purposes, even without constructing individual torso models from x-ray or from magnetic resonance images. 相似文献
40.
Kaija Valkonen Elisabetta Gianazza Pier Giorgio Righetti 《Clinica chimica acta; international journal of clinical chemistry》1980,107(3):223-229
We describe three basic modifications of our previous method for thalassemia screening by isoelectric focusing of heme-free globin chains: the gel thickness is reduced from 2 mm to 240 μm; the level of the detergent Nonidet P-40 in the gels is decreased from 3% to 0.5%; the polyacrylamide slab is covalently fixed to the supporting glass plate by treatment with silane A-174. By the present method the entire focusing process, starting from gel moulding up to gel destaining and drying, is completed within 4 h, a fraction of the time needed in our previous technique. More than a 100 samples can be analyzed per working day. The present technique also affords increased sensitivity: less than l μg protein/band is detected and less than 200 picomol of hemoglobin are needed for each analysis. Band sharpness and resolution in our ultrathin gels is also considerably increased. 相似文献