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81.
Höök H Ekegren MB Ericsson H Vågsholm I Danielsson-Tham ML 《Scandinavian journal of infectious diseases》2004,36(6-7):435-442
84 Campylobacter jejuni isolates from Swedish patients with domestic infection were characterized with pulsed-field gel electrophoresis (PFGE), and the subtype information considered in relation to epidemiological data. Based on pattern combinations from restriction cleavage with SmaI and SalI, 52 different PFGE types were identified. Types with an average pattern similarity of at least 82% and 63% were assembled in groups and clusters, respectively. The 2 largest clusters included 71% of the isolates. The distribution in time varied between different groups and clusters, where some were isolated sporadically during the whole period and others appeared more concentrated in time. Types in 1 cluster were significantly more often isolated in summer than other types in the study. Isolates from children showed lower pattern similarity to other isolates than isolates from adults. Sets of type and time related cases, possibly representing small outbreaks, were identified when indistinguishable PFGE patterns were found in isolates from temporally related cases. Our results indicate that although a large number of genotypes may be found among C. jejuni strains infecting humans, a large proportion of these may be genetically related, and that different genotypes may appear during different seasons and infect individuals of different ages. 相似文献
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Evaluation of an ICD‐10 algorithm to detect osteonecrosis of the jaw among cancer patients in the Danish National Registry of Patients 下载免费PDF全文
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Maternal Recall Error in Retrospectively Reported Time‐to‐Pregnancy: an Assessment and Bias Analysis 下载免费PDF全文
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Felix Zwicker Benedict Swartman Falk Roeder Florian Sterzing Henrik Hauswald Christian Thieke Klaus-Josef Weber Peter E. Huber Kai Schubert Jürgen Debus Klaus Herfarth 《Journal of radiation research》2015,56(2):239-247
In radiotherapy, in vivo measurement of dose distribution within patients'' lymphocytes can be performed by detecting gamma-H2AX foci in lymphocyte nuclei. This method can help in determining the whole-body dose. Options for risk estimations for toxicities in normal tissue and for the incidence of secondary malignancy are still under debate. In this investigation, helical tomotherapy (TOMO) is compared with step-and-shoot IMRT (SSIMRT) of the prostate gland by measuring the dose distribution within patients'' lymphocytes. In this prospective study, blood was taken from 20 patients before and 10 min after their first irradiation fraction for each technique. The isolated leukocytes were fixed 2 h after radiation. DNA double-stranded breaks in lymphocyte nuclei were stained immunocytochemically using anti-gamma-H2AX antibodies. Gamma-H2AX foci distribution in lymphocytes was determined for each patient. Using a calibration line, dose distributions in patients'' lymphocytes were determined by studying the gamma-H2AX foci distribution, and these data were used to generate a cumulative dose–lymphocyte histogram (DLH). Measured in vivo (DLH), significantly fewer lymphocytes indicated low-dose exposure (<40% of the applied dose) during TOMO compared with SSIMRT. The dose exposure range, between 45 and 100%, was equal with both radiation techniques. The mean number of gamma-H2AX foci per lymphocyte was significantly lower in the TOMO group compared with the SSIMRT group. In radiotherapy of the prostate gland, TOMO generates a smaller fraction of patients'' lymphocytes with low-dose exposure relative to the whole body compared with SSIMRT. Differences in the constructional buildup of the different linear accelerator systems, e.g. the flattening filter, may be the cause thereof. The influence of these methods on the incidence of secondary malignancy should be investigated in further studies. 相似文献
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Storage time of platelet concentrates and risk of a positive blood culture: a nationwide cohort study 下载免费PDF全文