26 resultados para 333.38


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We measured the concentrations and isotopic compositions of He, Ne, and Ar in bulk samples and metal separates of 14 ordinary chondrite falls with long exposure ages and high metamorphic grades. In addition, we measured concentrations of the cosmogenic radionuclides 10Be, 26Al, and 36Cl in metal separates and in the nonmagnetic fractions of the selected meteorites. Using cosmogenic 36Cl and 36Ar measured in the metal separates, we determined 36Cl-36Ar cosmic-ray exposure (CRE) ages, which are shielding-independent and therefore particularly reliable. Using the cosmogenic noble gases and radionuclides, we are able to decipher the CRE history for the studied objects. Based on the correlation 3He/21Ne versus 22Ne/21Ne, we demonstrate that, among the meteorites studied, only one suffered significant diffusive losses (about 35%). The data confirm that the linear correlation 3He/21Ne versus 22Ne/21Ne breaks down at high shielding. Using 36Cl-36Ar exposure ages and measured noble gas concentrations, we determine 21Ne and 38Ar production rates as a function of 22Ne/21Ne. The new data agree with recent model calculations for the relationship between 21Ne and 38Ar production rates and the 22Ne/21Ne ratio, which does not always provide unique shielding information. Based on the model calculations, we determine a new correlation line for 21Ne and 38Ar production rates as a function of the shielding indicator 22Ne/21Ne for H, L, and LL chondrites with preatmospheric radii less than about 65 cm. We also calculated the 10Be/21Ne and 26Al/21Ne production rate ratios for the investigated samples, which show good agreement with recent model calculations.

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Thema des Bandes ist die in der internationalen Praxis der Editionswissenschaft beobachtbare Vielfalt von wissenschaftsgeschichtlichen Traditionen, texttheoretischen Zugängen und editionspragmatischen Verfahren, die häufig aus der jeweils unterschiedlichen Entwicklung einzelner Nationalphilologien und ihrer tragenden Institutionen resultiert. Diese Heterogenität bereichert die länder- und sprachübergreifende editionswissenschaftliche Kommunikation, erschwert sie aber auch. Hinzu tritt die Tatsache, dass die Editionswissenschaft zunehmend in einem interdisziplinären Austausch steht, an dem in jüngerer Zeit auch die Informations- und Naturwissenschaften teilhaben. In einer von beschleunigter Kommunikation und Globalisierung geprägten Wissensgesellschaft berühren und vermischen sich diese verschiedenen Ansätze, dies nicht zuletzt im Kontext medialer Veränderungen. Zugleich erweisen sich nationale und fachspezifische Konventionen auch unter diesen gewandelten Bedingungen als erstaunlich zählebig – sie bestimmen wissenschaftliche Formen der Interaktion und Kooperation mitunter mehr, als dies den beteiligten Partnern bewusst ist. Diese komplexe Situation bildet den Rahmen für die im Band versammelten Beiträge, die sich mit dem ‚Dazwischen‘ (inter), d.h. mit Synergien und Brüchen nationaler und disziplinärer Zugänge in der Editionswissenschaft auseinandersetzen. Sie dokumentieren die Praxis des gegenwärtigen editorischen Alltags und zeigen, wie unterschiedliche textliche und methodische Voraussetzungen das editorische Endprodukt prägen.

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CONTEXT Subclinical hypothyroidism has been associated with increased risk of coronary heart disease (CHD), particularly with thyrotropin levels of 10.0 mIU/L or greater. The measurement of thyroid antibodies helps predict the progression to overt hypothyroidism, but it is unclear whether thyroid autoimmunity independently affects CHD risk. OBJECTIVE The objective of the study was to compare the CHD risk of subclinical hypothyroidism with and without thyroid peroxidase antibodies (TPOAbs). DATA SOURCES AND STUDY SELECTION A MEDLINE and EMBASE search from 1950 to 2011 was conducted for prospective cohorts, reporting baseline thyroid function, antibodies, and CHD outcomes. DATA EXTRACTION Individual data of 38 274 participants from six cohorts for CHD mortality followed up for 460 333 person-years and 33 394 participants from four cohorts for CHD events. DATA SYNTHESIS Among 38 274 adults (median age 55 y, 63% women), 1691 (4.4%) had subclinical hypothyroidism, of whom 775 (45.8%) had positive TPOAbs. During follow-up, 1436 participants died of CHD and 3285 had CHD events. Compared with euthyroid individuals, age- and gender-adjusted risks of CHD mortality in subclinical hypothyroidism were similar among individuals with and without TPOAbs [hazard ratio (HR) 1.15, 95% confidence interval (CI) 0.87-1.53 vs HR 1.26, CI 1.01-1.58, P for interaction = .62], as were risks of CHD events (HR 1.16, CI 0.87-1.56 vs HR 1.26, CI 1.02-1.56, P for interaction = .65). Risks of CHD mortality and events increased with higher thyrotropin, but within each stratum, risks did not differ by TPOAb status. CONCLUSIONS CHD risk associated with subclinical hypothyroidism did not differ by TPOAb status, suggesting that biomarkers of thyroid autoimmunity do not add independent prognostic information for CHD outcomes.

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PURPOSE Thoracic ultrasound (TUS) has been successfully used in the diagnosis of community-acquired pneumonia. Little is known about its diagnostic potential in ventilator-associated pneumonia (VAP). The purpose of this study was to systematically describe the morphology and temporal changes of sonographic patterns in mechanically ventilated patients and to evaluate the diagnostic performance characteristics of TUS-based VAP diagnoses. MATERIALS AND METHODS Patients who were placed on invasive ventilation for reasons other than pneumonia and who were considered at risk for the development of VAP received daily TUS examinations while being closely monitored for the development of pneumonia. RESULTS Fifty-seven patients were studied. The incidence of VAP was 21.1%. Sonographic patterns of reduced or absent lung aeration were found in 64.2% of examinations. The sonographic pattern of lung consolidation with either dynamic or static air bronchograms was 100% sensitive and 60% specific for VAP in those patients who developed clinical signs and symptoms compatible with pneumonia. The pretest and posttest probabilities were 0.38 and 0.6, respectively. CONCLUSIONS Sonographic patterns of abnormal aeration are frequently observed in mechanically ventilated patients. If sonographic lung consolidation with either static or dynamic air bronchograms is absent, VAP is highly unlikely. The presence of these sonographic patterns in patients with signs and symptoms suggestive of pneumonia significantly increases the probability of VAP.

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A protected S-acetylthio porphyrin was synthesized and attached to the Au38(2-phenylethanethiolate)24 cluster in a ligand exchange reaction. Chiral high performance liquid chromatography of the functionalized cluster yielded enantiomeric pairs of clusters probably differing in the binding site of the porphyrin. As proven by circular dichroism, the chirality was maintained. Exciton coupling between the cluster and the chromophore is observed. Zinc can be incorporated into the porphyrin attached to the cluster, as evidenced by absorption and fluorescence spectroscopy, however, the reaction is slow. Quenching of the chromophore fluorescence is observed, which can be explained by energy transfer from the porphyrin to the cluster. Transient absorption spectra of Au38(2-phenylethanethiolate)24 and the functionalized cluster probe the bleach of the gold cluster due to ground state absorption and the characteristic excited state absorption signals. Zinc incorporation does not have a pronounced effect on the photophysical behaviour. Decay times are typical for the molecular behaviour of small monolayer protected gold clusters.

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A 23-month-old tomcat was referred to our clinic because of male behavioral problems, cryptorchidism, and an undefined intra-abdominal organ resembling a uterus. Ultrasonography and computed tomography showed 2 fluid-filled tubular structures dorsolaterally to the bladder and connected to the pelvic urethra. The cat was castrated, and the tubular structures were surgically removed. Histology identified them as Müllerian duct remnants. The testes were hypoplastic, the epididymes and deferent ducts were normal. Cytogenetic analyses revealed the presence of a mosaic 37,X/38,XY karyotype which explains the clinical findings.

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AbstractBackground It is not easy to overview pending phase 3 trials on prostate cancer (PCa), and awareness of these trials would benefit clinicians. Objective To identify all phase 3 trials on {PCa} registered in the ClinicalTrials.gov database with pending results. Design and setting On September 29, 2014, a database was established from the records for 175 538 clinical trials registered on ClinicalTrials.gov. A search of this database for the substring “prostat” identified 2951 prostate trials. Phase 3 trials accounted for 441 studies, of which 333 concerned only PCa. We selected only ongoing or completed trials with pending results, that is, for which the primary endpoint had not been published in a peer-reviewed medical journal. Results and limitations We identified 123 phase 3 trials with pending results. Trials were conducted predominantly in North America (n = 63; 51) and Europe (n = 47; 38). The majority were on nonmetastatic disease (n = 82; 67), with 37 (30) on metastatic disease and four trials (3) including both. In terms of intervention, systemic treatment was most commonly tested (n = 71; 58), followed by local treatment 34 (28), and both systemic and local treatment (n = 11; 9), with seven (6) trials not classifiable. The 71 trials on systemic treatment included androgen deprivation therapy (n = 34; 48), chemotherapy (n = 15; 21), immunotherapy (n = 9; 13), other systemic drugs (n = 9; 13), radiopharmaceuticals (n = 2; 3), and combinations (n = 2; 3). Local treatments tested included radiation therapy (n = 27; 79), surgery (n = 5; 15), and both (n = 2; 2). A limitation is that not every clinical trial is registered on ClinicalTrials.gov. Conclusion There are many {PCa} phase 3 trials with pending results, most of which address questions regarding systemic treatments for both nonmetastatic and metastatic disease. Radiation therapy and androgen deprivation therapy are the interventions most commonly tested for local and systemic treatment, respectively. Patient summary This report describes all phase 3 trials on prostate cancer registered in the ClinicalTrials.gov database with pending results. Most of these trials address questions regarding systemic treatments for both nonmetastatic and metastatic disease. Radiation therapy and androgen deprivation therapy are the interventions most commonly tested for local and systemic treatment, respectively.

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PURPOSE Our main objective was to prospectively determine the prognostic value of [(18)F]fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) after two cycles of rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone given every 14 days (R-CHOP-14) under standardized treatment and PET evaluation criteria. PATIENTS AND METHODS Patients with any stage of diffuse large B-cell lymphoma were treated with six cycles of R-CHOP-14 followed by two cycles of rituximab. PET/CT examinations were performed at baseline, after two cycles (and after four cycles if the patient was PET-positive after two cycles), and at the end of treatment. PET/CT examinations were evaluated locally and by central review. The primary end point was event-free survival at 2 years (2-year EFS). RESULTS Median age of the 138 evaluable patients was 58.5 years with a WHO performance status of 0, 1, or 2 in 56%, 36%, or 8% of the patients, respectively. By local assessment, 83 PET/CT scans (60%) were reported as positive and 55 (40%) as negative after two cycles of R-CHOP-14. Two-year EFS was significantly shorter for PET-positive compared with PET-negative patients (48% v 74%; P = .004). Overall survival at 2 years was not significantly different, with 88% for PET-positive versus 91% for PET-negative patients (P = .46). By using central review and the Deauville criteria, 2-year EFS was 41% versus 76% (P < .001) for patients who had interim PET/CT scans after two cycles of R-CHOP-14 and 24% versus 72% (P < .001) for patients who had PET/CT scans at the end of treatment. CONCLUSION Our results confirmed that an interim PET/CT scan has limited prognostic value in patients with diffuse large B-cell lymphoma homogeneously treated with six cycles of R-CHOP-14 in a large prospective trial. At this point, interim PET/CT scanning is not ready for clinical use to guide treatment decisions in individual patients.