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81.
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
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Daniel Klintman René Schramm Michael D Menger Henrik Thorlacius 《Journal of hepatology》2002,36(1):53-59
BACKGROUND/AIMS: This study was designed to examine the role of selectins and CD18 in leukocyte recruitment in hepatic injury induced by tumor necrosis factor-alpha (TNF-alpha) and galactosamine (Gal) in vivo. METHODS: Intravital fluorescence microscopy of the hepatic microcirculation was used to quantify leukocyte-endothelium interactions provoked by 24 h of systemic TNF-alpha/Gal challenge in rats. Hepatic injury was evaluated with liver enzymes. RESULTS: When administered after 24 h of TNF-alpha/Gal challenge, fucoidan, a selectin-function inhibitor, reduced leukocyte rolling by 69%, whereas firm adhesion was unaltered. In contrast, passive immunization against CD18 decreased leukocyte adhesion by 60%, whereas rolling remained unchanged. Notably, when administered prior to TNF-alpha/Gal, fucoidan attenuated both leukocyte rolling and adhesion, by 57 and 69%, respectively. Pretreatment with an anti-CD18 antibody decreased TNF-alpha/Gal-induced rolling and firm adhesion by 25 and 90%, respectively. Moreover, pretreatment with fucoidan and the anti-CD18 antibody both protected against TNF-alpha/Gal-induced increases in liver enzymes. For example, the pretreatments reduced alanine aminotransferase by 59 and 87%, respectively. CONCLUSIONS: Our data suggest that TNF-alpha/Gal-induced leukocyte rolling is selectin-mediated and a precondition for CD18-dependent firm adhesion in hepatic venules. Thus, reducing leukocyte recruitment by inhibition of selectins or CD18 may be useful to control TNF-alpha-induced liver injury. 相似文献
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Positive blood cultures and diagnosis of bacterial meningitis in cases with negative culture of cerebrospinal fluid 总被引:1,自引:0,他引:1
Fuglsang-Damgaard D Pedersen G Schønheyder HC 《Scandinavian journal of infectious diseases》2008,40(3):229-233
The diagnosis of bacterial meningitis may be established through positive blood cultures in cases with negative culture of cerebrospinal fluid (CSF). However, information is sparse regarding how often the aetiological diagnosis is determined by blood culture alone. Therefore, we undertook a retrospective study of patients with meningitis and a blood culture-based bacterial diagnosis in North Jutland County, Denmark in 1997-2005. Patients were included if they had 1) a microscopy- and culture-negative CSF specimen with a leukocyte count > or =100x10(6)/l and an erythrocyte count < or =10,000x10(6)/l and 2) a positive blood culture within an interval of 3 d. A total of 20 patients fulfilled these criteria: 7 with Streptococcus pneumoniae, 4 with Neisseria meningitidis, 4 with Staphylococcus aureus, and 5 with miscellaneous bacteria. Suitable antibiotic therapy was delayed up to 48 h after lumbar puncture, and in-hospital mortality was 25%. A discharge diagnosis of bacterial meningitis was missing in 6/20 cases, and 12/20 cases had not been reported to Danish health authorities. Thus, patients with CSF-culture negative bacterial meningitis are at risk of delayed therapy, a poor outcome, and incomplete notification to health authorities. 相似文献
89.
Pulmonary function and bronchial reactivity in asthmatics during low-level formaldehyde exposure 总被引:1,自引:0,他引:1
This study evaluated whether formaldehyde, at concentrations similar to those found in the indoor environment, could produce adverse effects on the lower airway of 15 asthmatic persons with documented bronchial hyperresponsiveness who were exposed for 90 min in a climate chamber to clean air containing formaldehyde vapor at levels of 0.85 mg/m3, 0.12 mg/m3, and 0.008 mg/m3. No significant changes in forced expiratory volume in 1 sec (FEV1), airway resistance (Raw), specific airway resistance (SRaw), and flow-volume curves could be detected during formaldehyde exposure. Furthermore, histamine challenge tests performed immediately after formaldehyde exposure showed no evidence of changes in bronchial reactivity. No late reactions were registered during the first 14-16 hr after exposure. The results suggest that residential levels of formaldehyde are of minor importance in the emergence of pulmonary symptoms. Discrepancies between the present study and previous data may be due to differences in environmental conditions. 相似文献
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Heiko?AselmannEmail authorView authors OrcID profile Jan-Niclas?Kersebaum Alexander?Bernsmeier Jan?Henrik?Beckmann Thorben?M?ller Jan?Hendrik?Egberts Clemens?Schafmayer Christoph?R?cken Thomas?Becker 《International journal of colorectal disease》2018,33(11):1575-1581