293 research outputs found

    Geology and geochemistry of the Redrock Granite and anorthosite xenoliths (Proterozoic) in the northern Burro Mountains, Grant County, New Mexico, USA

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    Mineral ages from the A-type granites and anorthosite xenoliths in the Redrock area in the northwestern Burro Mountains in southwestern New Mexico cluster around ~1220–1225 Ma and provide yet another example of bimodal igneous activity during this time period in the southwestern United States. The metaluminous to peraluminous, marginally alkaline to subalkaline Redrock Granite exhibits the textural, mineralogical, and geochemical features of A-type granitethat was emplaced at a relatively high crustal level. Field relationships, whole rock and mineral geochemical and isotopic trends suggest that the four phases of the Redrock Granite are genetically related, with the miarolitic biotite/alkali feldspar granite being the youngest phase. Spatial relationships and geochemical data suggest that the anorthosite xenoliths were coeval with the RedrockGranite, which is consistent with the anorthosite being derived from the upper mantle, possibly due to deep mantle upwellings, and the Redrock Granite from the lower crust. The process involved melting in the upper mantle, emplacement of anorthosite in the crust resulting in partial crustal melting and thinning, and, finally, intrusion of shallow silicic plutons, the Redrock Granite. The Redrock Granite and anorthosite were presumably derived from sources characterized by subtle, long-term LREE depletion, with εNd (at 1220 Ma) values on theorder of +1 to +2

    Calibration of dosemeters used in mammography with different X ray qualities: Euromet Project No. 526

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    The effect of different X ray radiation qualities on the calibration of mammographic dosemeters was investigated within the framework of a EUROMET (European Collaboration in Measurement Standards) project. The calibration coefficients for two ionization chambers and two semiconductor detectors were established in 13 dosimetry calibration laboratories for radiation qualities used in mammography. They were compared with coefficients for other radiation qualities, including those defined in ISO 4037-1, with first half value layers in the mammographic range. The results indicate that the choice of the radiation quality is not crucial for instruments with a small energy dependence of the response. However, the radiation quality has to be chosen carefully if instruments with a marked dependence of their response to the radiation energy are calibrate

    Gastric cancer and Helicobacter pylori: a combined analysis of 12 case control studies nested within prospective cohorts

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    BACKGROUND: The magnitude of the association between Helicobacter pylori and incidence of gastric cancer is unclear. H pylori infection and the circulating antibody response can be lost with development of cancer; thus retrospective studies are subject to bias resulting from classifi- cation of cases as H pylori negative when they were infected in the past. AIMS: To combine data from all case control studies nested within prospective cohorts to assess more reliably the relative risk of gastric cancer associated with H pylori infection.To investigate variation in relative risk by age, sex, cancer type and subsite, and interval between blood sampling and cancer diagnosis. METHODS: Studies were eligible if blood samples for H pylori serology were collected before diagnosis of gastric cancer in cases. Identified published studies and two unpublished studies were included. Individual subject data were obtained for each. Matched odds ratios (ORs) and 95% confidence intervals (95% CI) were calculated for the association between H pylori and gastric cancer. RESULTS: Twelve studies with 1228 gastric cancer cases were considered. The association with H pylori was restricted to noncardia cancers (OR 3.0; 95% CI 2.3–3.8) and was stronger when blood samples for H pylori serology were collected 10+ years before cancer diagnosis (5.9; 3.4–10.3). H pylori infection was not associated with an altered overall risk of cardia cancer (1.0; 0.7–1.4). CONCLUSIONS: These results suggest that 5.9 is the best estimate of the relative risk of non-cardia cancer associated with H pylori infection and that H pylori does not increase the risk of cardia cancer. They also support the idea that when H pylori status is assessed close to cancer diagnosis, the magnitude of the non-cardia association may be underestimated

    Successful Curriculum Change in Health Management and Leadership Studies for the Specialist Training Programs in Medicine in Finland

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    In Finland, the specialization programs in Medicine and Dentistry can be undertaken at all five university medical faculties in 50 specialization programs and in five programs for Dentistry. The specialist training requires 5 or 6 years (300–360 ECTS credits) of medical practice including 9 months of service in primary health care centers, theoretical substance specific education, management studies, and passing a national written exam. The renovation of the national curriculum for the specialization programs was implemented, first in 2008 and officially in August 2009, when theoretical multi-professional social, health management and leadership studies (10–30 ECTS credits) were added to the curriculum. According to European Credit Transfer and Accumulation System (ECTS), 1 ECTS credit (henceforth, simply “ECTS”) means 27–30 h of academic work1 National guidelines for the multi-professional leadership training include the basics of organizational management and leadership, the social and healthcare system, human resources (HR) management, leadership interaction and organizational communication, healthcare economy, legislation (HR) and data management. Each medical faculty has implemented management studies autonomously but according to national guidelines. This paper will describe how the compulsory management studies (10 ECTS) have been executed at the Universities of Tampere and Turku. In Tampere, the 10 ECTS management studies follow a flexible design of six academic modules. Versatile modern teaching methods such as technology-assisted and student orientated learning are used. Advanced supplementary management studies (20 ECTS) are also available. In Turku, the 10 ECTS studies consist of academic lectures, portfolio and project work. Attendees select contact studies (4–6 ECTS) from yearly available 20 ECTS and proceed at their own pace. Portfolio and project comprise 2–5 ECTS each. The renovation of medical specializing physicians' management and leadership education has been a successful reform. It has been observed that positive attitudes and interest toward management overall are increasing among younger doctors. In addition, management and leadership education will presumably facilitate medical doctors' work as managers also. Continuous development of medical doctors' management and leadership education for physicians and dentists is needed while the changing and complex healthcare environment requires both professional and leadership expertise

    Centralized repeated resectability assessment of patients with colorectalliver metastases during first-line treatment : prospective study

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    Y Background: Metastasectomy is probably underused in metastatic colorectal cancer. The aim of this study was to investigate the effect of centralized repeated assessment on resectability rate of liver metastases. Methods: The prospective RAXO study was a nationwide study in Finland. Patients with treatable metastatic colorectal cancer at any site were eligible. This planned substudy included patients with baseline liver metastases between 2012 and 2018. Resectability was reassessed by the multidisciplinary team at Helsinki tertiary referral centre upfront and twice during first-line systemic therapy. Outcomes were resectability rates, management changes, and survival. Results: Of 812 patients included, 301 (37.1 per cent) had liver-only metastases. Of these, tumours were categorized as upfront resectable in 161 (53.5 per cent), and became amenable to surgery during systemic treatment in 63 (20.9 per cent). Some 207 patients (68.7 per cent) eventually underwent liver resection or ablation. At baseline, a discrepancy in resectability between central and local judgement was noted for 102 patients (33.9 per cent). Median disease-free survival (DFS) after first resection was 20 months and overall survival (OS) 79 months. Median OS after diagnosis of metastatic colorectal cancer was 80, 32, and 21 months in R0-1 resection, R2/ablation, and non-resected groups, and 5-year OS rates were 68, 37, and 9 per cent, respectively. Liver and extrahepatic metastases were present in 511 patients. Of these, tumours in 72 patients (14.1 per cent) were categorized as upfront resectable, and 53 patients (10.4 per cent) became eligible for surgery. Eventually 110 patients (21.5 per cent) underwent liver resection or ablation. At baseline, a discrepancy between local and central resectability was noted for 116 patients (22.7 per cent). Median DFS from first resection was 7 months and median OS 55 months. Median OS after diagnosis of metastatic colorectal cancer was 79, 42, and 17 months in R0-1 resection, R2/ablation, and non-resected groups, with 5-year OS rates of 65, 39, and 2 per cent, respectively. Conclusion: Repeated centralized resectability assessment in patients with colorectal liver metastases improved resection and survival rates.Peer reviewe

    What predicts doctors’ satisfaction with their chosen medical specialty? A Finnish national study

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    Background In Finland the number of medical specialists varies between specialties and regions. More regulation of the post-graduate medical training is planned. Therefore, it is important to clarify what predicts doctors’ satisfaction with their chosen specialty. Methods A random sample contained 50 % of all Finnish doctors under 70 years of age. The respose rate was 50.5 %. Working-age specialists were asked to value their motives when choosing a specialty. They were also asked if they would choose the same specialty again. The odds ratios for not choosing the same specialty again were tested. Results Diversity of work was the most important motive (74 % of respondents). Seventeen percent of GPs would not choose the same specialty again, compared to 2 % of ophthalmologists and 4 % of pediatricians. A major role of Diversity of work and Prestigious field correlated with satisfaction whereas Chance with dissatisfaction with the specialty. Discussion Motives and issues related to the work and training best correlate with satisfaction with the specialty. Conclusions When the numbers of Finnish postgraduate medical training posts become regulated, a renewed focus should be given to finding the most suitable speciality for each doctor. Information about employment and career advice should play an important role in this.BioMed Central open acces

    Helicobacter pylori (H pylori) infection in Greece: the changing prevalence during a ten-year period and its antigenic profile

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    BACKGROUND: To evaluate changes in H pylori infection prevalence in Greece during a ten-year period, and to examine its antigenic profile. METHODS: Three groups of patients were studied. Group O-87: Banked serum samples of 200 consecutive adult outpatients, from the Hepato-Gastroenterology clinic of a teaching hospital at Athens, collected in 1987. Group O-97: Serum samples of 201 similarly selected outpatients from the same Unit, collected in 1997. Group BD-97: Serum samples of 120 consecutive blood donors from the same hospital, collected in 1997. H pylori IgG antibody seroprevalence was studied by a quantitative ELISA. Antigenic profile was studied by western-blot IgG assay, in 62 IgG positive patients of O-97 and BD-97. Results were analyzed by conventional statistics and multivariate regression analysis. RESULTS: The H pylori seroprevalence increased with age in the three tested groups. In O-97, seroprevalence did not differ from that, in BD-97. On the contrary, there was a significant decrease in seropositivity between O-87 and O-97 (59.5% vs 49.2%, p = 0.039). Multiple regression analysis showed that age over 35 years (OR:3.45, 95% CI:1.59–7.49, p = 0.002) and year of patients' selection – that is 1987 or 1997 – (OR:1.73, 95% CI:1.14–2.65 for 1987, p = 0.010), were independent risk factors of H pylori infection. The seroprevalence of CagA+ and VacA+ strains was 77.4% and 58.5%, respectively, and type I(CagA+/VacA+) strains were significantly more common than type II(CagA-/VacA-) strains (59.7% vs 22.6%, p < 0.001). CONCLUSIONS: During a ten-year period, we found a significant decrease of H pylori infection in Greece and our data support the birth cohort phenomenon as an explanation for the age-dependent increase of H pylori infection. The prevalence of CagA and/or VacA positive strains is relatively high, in a country with low incidence of gastric cancer
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