934 resultados para Dolliver, Jonathan P. (Jonathan Prentiss), 1858-1910.
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OBJECTIVE To compare the accuracy of radiography and computed tomography (CT) in predicting implant position in relation to the vertebral canal in the cervical and thoracolumbar vertebral column. STUDY DESIGN In vitro imaging and anatomic study. ANIMALS Medium-sized canine cadaver vertebral columns (n=12). METHODS Steinmann pins were inserted into cervical and thoracolumbar vertebrae based on established landmarks but without predetermination of vertebral canal violation. Radiographs and CT images were obtained and evaluated by 6 individuals. A random subset of pins was evaluated for ability to distinguish left from right pins on radiographs. The ability to correctly identify vertebral canal penetration for all pins was assessed both on radiographs and CT. Spines were then anatomically prepared and visual examination of pin penetration into the canal served as the gold standard. RESULTS Left/right accuracy was 93.1%. Overall sensitivity of radiographs and CT to detect vertebral canal penetration by an implant were significantly different and estimated as 50.7% and 93.4%, respectively (P<.0001). Sensitivity was significantly higher for complete versus partial penetration and for radiologists compared with nonradiologists for both imaging modalities. Overall specificity of radiographs and CT to detect vertebral canal penetration was 82.9% and 86.4%, respectively (P=.049). CONCLUSIONS CT was superior to radiographic assessment and is the recommended imaging modality to assess penetration into the vertebral canal. CLINICAL RELEVANCE CT is significantly more accurate in identifying vertebral canal violation by Steinmann pins and should be performed postoperatively to assess implant position.
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The objectives of this study were to describe a new spinal cord injury scale for dogs, evaluate repeatability through determining inter-rater variability of scores, compare these scores to another established system (a modified Frankel scale), and determine if the modified Frankel scale and the newly developed scale were useful as prognostic indicators for return to ambulation. A group of client-owned dogs with spinal cord injury were examined by 2 independent observers who applied the new Texas Spinal Cord Injury Score (TSCIS) and a modified Frankel scale that has been used previously. The newly developed scale was designed to describe gait, postural reactions and nociception in each limb. Weighted kappa statistics were utilized to determine inter-rater variability for the modified Frankel scale and individual components of the TSCIS. Comparisons were made between raters for the overall TSCIS score and between scales using Spearman's rho. An additional group of dogs with surgically treated thoracolumbar disk herniation was enrolled to look at correlation of both scores with spinal cord signal characteristics on magnetic resonance imaging (MRI) and ambulatory outcome at discharge. The actual agreement between raters for the modified Frankel scale was 88%, with a weighted kappa value of 0.93. The TSCIS had weighted kappa scores for gait, proprioceptive positioning and nociception components that ranged from 0.72 to 0.94. Correlation between raters for the overall TSCIS score was Spearman's rho=0.99 (P<0.001). Comparison of the overall TSCIS score to the modified Frankel score resulted in a Spearman's rho value of 0.90 (P<0.001). The modified Frankel score was weakly correlated with the length of hyperintensity of the spinal cord: L2 vertebral body length ratio on mid-sagittal T2-weighted MRI (Spearman's rho=-0.45, P=0.042) as was the overall TSCIS score (Spearman's rho=-0.47, P=0.037). There was also a significant difference in admitting modified Frankel scores (P=0.029) and admitting overall TSCIS scores (P=0.02) between dogs that were ambulatory at discharge and those that were not. Results from this study suggest that the TSCIS is an easy to administer scale for evaluating canine spinal cord injury based on the standard neurological exam and correlates well with a previously described modified Frankel scale.
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OBJECTIVE To determine the success of medical management of presumptive cervical disk herniation in dogs and variables associated with treatment outcome. DESIGN Retrospective case series. ANIMALS Dogs (n=88) with presumptive cervical disk herniation. METHODS Dogs with presumptive cervical and thoracolumbar disk herniation were identified from medical records at 2 clinics and clients were mailed a questionnaire related to the success of therapy, clinical recurrence of signs, and quality of life (QOL) as interpreted by the owner. Signalment, duration and degree of neurologic dysfunction, and medication administration were determined from medical records. RESULTS Ninety-seven percent of dogs (84/87) with complete information were described as ambulatory at initial evaluation. Successful treatment was reported for 48.9% of dogs with 33% having recurrence of clinical signs and 18.1% having therapeutic failure. Bivariable logistic regression showed that non-steroidal anti-inflammatory drug (NSAID) administration was associated with success (P=.035; odds ratio [OR]=2.52). Duration of cage rest and glucocorticoid administration were not significantly associated with success or QOL. Dogs with less-severe neurologic dysfunction were more likely to have a successful outcome (OR=2.56), but this association was not significant (P=.051). CONCLUSIONS Medical management can lead to an acceptable outcome in many dogs with presumptive cervical disk herniation. Based on these data, NSAIDs should be considered as part of the therapeutic regimen. Cage rest duration and glucocorticoid administration do not appear to benefit these dogs, but this should be interpreted cautiously because of the retrospective data collection and use of client self-administered questionnaire follow-up. CLINICAL RELEVANCE These results provide insight into the success of medical management for presumptive cervical disk herniation in dogs and may allow for refinement of treatment protocols.
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OBJECTIVE To determine the success of medical management of presumptive thoracolumbar disk herniation in dogs and the variables associated with treatment outcome. STUDY DESIGN Retrospective case series. ANIMALS Dogs (n=223) with presumptive thoracolumbar disk herniation. METHODS Medical records from 2 clinics were used to identify affected dogs, and owners were mailed a questionnaire about success of therapy, recurrence of clinical signs, and quality of life (QOL) as interpreted by the owner. Signalment, duration and degree of neurologic dysfunction, and medication administration were determined from medical records. RESULTS Eighty-three percent of dogs (185/223) were ambulatory at initial evaluation. Successful treatment was reported for 54.7% of dogs, with 30.9% having recurrence of clinical signs and 14.4% classified as therapeutic failures. From bivariable logistic regression, glucocorticoid administration was negatively associated with success (P=.008; odds ratio [OR]=.48) and QOL scores (P=.004; OR=.48). The duration of cage rest was not significantly associated with success or QOL. Nonambulatory dogs were more likely to have lower QOL scores (P=.01; OR=2.34). CONCLUSIONS Medical management can lead to an acceptable outcome in many dogs with presumptive thoracolumbar disk herniation. Cage rest duration does not seem to affect outcome and glucocorticoids may negatively impact success and QOL. The conclusions in this report should be interpreted cautiously because of the retrospective data collection and the use of client self-administered questionnaire follow-up. CLINICAL RELEVANCE These results provide an insight into the success of medical management for presumptive thoracolumbar disk herniation in dogs and may allow for refinement of treatment protocols.
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BACKGROUND VEGF and VEGF receptor-2-mediated angiogenesis contribute to hepatocellular carcinoma pathogenesis. Ramucirumab is a recombinant IgG1 monoclonal antibody and VEGF receptor-2 antagonist. We aimed to assess the safety and efficacy of ramucirumab in advanced hepatocellular carcinoma following first-line therapy with sorafenib. METHODS In this randomised, placebo-controlled, double-blind, multicentre, phase 3 trial (REACH), patients were enrolled from 154 centres in 27 countries. Eligible patients were aged 18 years or older, had hepatocellular carcinoma with Barcelona Clinic Liver Cancer stage C disease or stage B disease that was refractory or not amenable to locoregional therapy, had Child-Pugh A liver disease, an Eastern Cooperative Oncology Group performance status of 0 or 1, had previously received sorafenib (stopped because of progression or intolerance), and had adequate haematological and biochemical parameters. Patients were randomly assigned (1:1) to receive intravenous ramucirumab (8 mg/kg) or placebo every 2 weeks, plus best supportive care, until disease progression, unacceptable toxicity, or death. Randomisation was stratified by geographic region and cause of liver disease with a stratified permuted block method. Patients, medical staff, investigators, and the funder were masked to treatment assignment. The primary endpoint was overall survival in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT01140347. FINDINGS Between Nov 4, 2010, and April 18, 2013, 565 patients were enrolled, of whom 283 were assigned to ramucirumab and 282 were assigned to placebo. Median overall survival for the ramucirumab group was 9·2 months (95% CI 8·0-10·6) versus 7·6 months (6·0-9·3) for the placebo group (HR 0·87 [95% CI 0·72-1·05]; p=0·14). Grade 3 or greater adverse events occurring in 5% or more of patients in either treatment group were ascites (13 [5%] of 277 patients treated with ramucirumab vs 11 [4%] of 276 patients treated with placebo), hypertension (34 [12%] vs ten [4%]), asthenia (14 [5%] vs five [2%]), malignant neoplasm progression (18 [6%] vs 11 [4%]), increased aspartate aminotransferase concentration (15 [5%] vs 23 [8%]), thrombocytopenia (13 [5%] vs one [<1%]), hyperbilirubinaemia (three [1%] vs 13 [5%]), and increased blood bilirubin (five [2%] vs 14 [5%]). The most frequently reported (≥1%) treatment-emergent serious adverse event of any grade or grade 3 or more was malignant neoplasm progression. INTERPRETATION Second-line treatment with ramucirumab did not significantly improve survival over placebo in patients with advanced hepatocellular carcinoma. No new safety signals were noted in eligible patients and the safety profile is manageable. FUNDING Eli Lilly and Co.
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OBJECTIVE To illustrate an approach to compare CD4 cell count and HIV-RNA monitoring strategies in HIV-positive individuals on antiretroviral therapy (ART). DESIGN Prospective studies of HIV-positive individuals in Europe and the USA in the HIV-CAUSAL Collaboration and The Center for AIDS Research Network of Integrated Clinical Systems. METHODS Antiretroviral-naive individuals who initiated ART and became virologically suppressed within 12 months were followed from the date of suppression. We compared 3 CD4 cell count and HIV-RNA monitoring strategies: once every (1) 3 ± 1 months, (2) 6 ± 1 months, and (3) 9-12 ± 1 months. We used inverse-probability weighted models to compare these strategies with respect to clinical, immunologic, and virologic outcomes. RESULTS In 39,029 eligible individuals, there were 265 deaths and 690 AIDS-defining illnesses or deaths. Compared with the 3-month strategy, the mortality hazard ratios (95% CIs) were 0.86 (0.42 to 1.78) for the 6 months and 0.82 (0.46 to 1.47) for the 9-12 month strategy. The respective 18-month risk ratios (95% CIs) of virologic failure (RNA >200) were 0.74 (0.46 to 1.19) and 2.35 (1.56 to 3.54) and 18-month mean CD4 differences (95% CIs) were -5.3 (-18.6 to 7.9) and -31.7 (-52.0 to -11.3). The estimates for the 2-year risk of AIDS-defining illness or death were similar across strategies. CONCLUSIONS Our findings suggest that monitoring frequency of virologically suppressed individuals can be decreased from every 3 months to every 6, 9, or 12 months with respect to clinical outcomes. Because effects of different monitoring strategies could take years to materialize, longer follow-up is needed to fully evaluate this question.
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Scan von Monochrom-Mikroform
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von Landgerichtssekretär H. Miller
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5 Briefe mit Antwort an Inga Haag, 1951-1955; 1 Brief mit Antwort von Jürgen Habermas an Max Horkheimer, 1955; 1 Brief von Ministerialrat i. R. Theodor Häbich an Max Horkheimer, 1957; 2 Briefe mit Antwort von cand. phil. Walter Hähnle an Max Horkheimer, 1955, 1957; 1 Brief mit Antwort von Sekretärin Jutta Hagen an Max Horkheimer, 1956; 1 Dissertationsauszug von Volker Freiherr von Hagen, 1954; 1 Brief mit Antwort von Julia Hagenbucher an Max Horkheimer, 1951/1952; 1 Entwurf zu einem Gratulationsschreiben von Max Horkheimer an Professor Otto Hahn, ohne Jahr; 2 Drucksachen von Obermagistratsrat Julius Hahn, 1953, 1955; 1 Brief mit Antwort von Theodor W. Adorno, von Dr. Hans Hahn an Max Horkheimer, 1952; 1 Brief von Theodor W. Adorno an Dr. Hans Hahn, 1952; 1 Danksagung von Rabbi Hugo Hahn, 1955; 3 Briefe mit Antwort von Paul Hahn an Max Horkheimer, 1951-1958; 1 Brief von Max Horkheimer an die Gebrüder Haldy, 1952; 1 Brief mit Antwort und Beilage von Professor George W. F. Hallgarten an Max Horkheimer, 1950; 1 Rundschreiben von Arzt und Psychotherapeut Hans Hammer, 1957; 1 Brief von Max Horkheimer an Margarete Hampf-Solm, 1955; 1 Brief mit Antwort von Professor Eduardo Hamuy an Max Horkheimer, 1952; 1 Brief von der Stadtärztin Dr. med. Carola Hannappel an Max Horkheimer, 1951; 1 Brief von Hansenmeister an Max Horkheimer, 1951; 1 Brief mit Antwort und Beilage von der Buchhandlung Ludwig Häntzschel an Max Horkheimer, 1958; 1 Brief von Professor Frederick Harris Harbison an Max Horkheimer, 1952; 3 Briefe mit Antwort von Robert Harcourt an Max Horkheimer, 1958; 1 Brief von Karl Hardach an Max Horkheimer, 1957; 1 Brief mit Antwort von Emilie Harlacher an Max Horkheimer, 1952; 1 Drucksache mit Antwort von Oberkirchenrat Otto L. A. von Harling an Max Horkheimer, 1955; 1 Brief mit Antwort von Gertrud Harms an Max Horkheimer, 1955; 2 Brief mit Antwort von Professor Wolfgang Hartke an Max Horkheimer, 1954-1956; 2 Briefe mit antwort von Max Horkheimer an Senator Georg Hartmann, 1951, 1954; 3 briefe mit Antwort und Beilage von Ökonom Heinz Hartmann an Max Horkheimer, 1956-1958; 1 Brief mit Antwort von Professor Wilbert E. Moore an Max Horkheimer, 1957; 3 Briefe mit Antwort und Beilage von Dr. phil. Leo Hartmann an Max Horkheimer, 1957-1858; 1 Brief mit Antowort von Dr. phil. Eckardt Mesch an Max Horkheimer, 1957; 1 Brief mit Antwort von Luzie Hatch an Max Horkheimer, 1954; 1 Brief von Max Horkheimer an den Direktor H. W. Haupt, 1950; 1 Drucksache von Haus Schwalbach, 1951; 4 Briefe mit Antwort von Professor Gottfried und Ellen Hausmann an Max Horkheimer, 1951-1958; 6 Briefe mit Antwort von Eva Haussner an Max Horkheimer, 1957, 1958; 1 Brief mit Antwort von Professor Robert J. Havighurst an Max Horkheimer, 1951; 1 Brief mit Beilage von Herbert Hax an Max Horkheimer, 1955; 2 Briefe mit Antwort und Beilage von Jean Louis Hébarre an Max Horkheimer, 1950-1952; 1 Brief mit Antwort von dem Hebedienst für Elektrizität, Gas und Wasser an Max Horkheimer, 1951; 5 Briefe mit Antwort und Beilage von Professor Otto Heckmann an Max Horkheimer, 1952, 1954; 1 Brief von Melvin J. Lasky an August Heckscher, 1957; 3 Briefe mit Antwort von Marie Heep an Max Horkheimer, 1956-1858; 1 Brief von der Buchhandlung Thekla Heer an Max Horkheimer, 1953; 1 Brief mit Antwort von dem Verleger Jakob Hegner an Max Horkheimer, 1955; 1 Brief von Dr. phil. Rudolf M. Heilbrunn an Max Horkheimer, 1953; 1 Brief mit Antwort von Professor Eduard Heimann an Max Horkheimer, 1952; 1 Brief von Professor Eduard Heimann an Theodor W. Adorno, 1957; 1 Brief mit Antwort von stud. phil. Wolfgang Heinrich an Max Horkheimer, 1958; 1 Brief von Max Horkheimer an den Direktor Helmuth Heintzmann, 1955; 1 Aktennotiz von Professor Bernhard Heller, 1956; 1 Brief mit Antwort von Philipp A. Heller an Max Horkheimer, 1952; 1 Brief von Max Horkheimer an Assistent Winfried Hellmann, 1957; 2 Briefe mit Antwort von Professor Arthur Henkel an Max Horkheimer, 1953/1954; 1 Brief von Max Horkheiemr an Dorothy Henkel, 1952; 2 Briefe mit Antwort von Dr. jur. Werner Hennig an Max Horkheimer, 1951; 1 Brief von Max Horkheimer an Professor Wilhelm Hennis, 1957; 3 Briefe mit Antwort und Beilage von Professor Fritz Hepner an Max Horkheimer, 1953; 1 Brief von Max Horkheimer an den Hessischer Minister für Erziehung und Volksbildung, 1950; 1 Brief mit Antwort von Professor Henrietta Herbolsheimer an Max Horkheimer, 1957/1958; 2 Briefe mit Antwort von P. G. Herbst an Max Horkheimer, 1952; 1 Brief von Max Horkheimer an den Herder Verlag, 1953; 2 Briefe mit Antwort, Beilagen und Aktennotizen von Guenter R. Herz an Max Horkheimer, 1956-1957; 2 Briefe mit Antwort unv Beilagen von Professor Theodor W. Adorno, von Dr. phil. Günther Herzberg an Max Horkheimer, 1951-1953; 1 Brief von Professor Theodor W. Adrono an Dr. phil. Günther Herzberg, 1951; 1 Brief von Dr. phil. G. Herzfeld an Max Horkheimer, 1952; 1 Brief von dem Herzog-Film an Max Horkheimer, 1952; 1 Brief mit Antwort von Professor Theodor W. Adorno, von Professor Erich Herzog an Max Horkheimer, 1952; 1 Brief von Professor Theodor W. Adorno an Professor Erich Herzog, 1952; 1 Brief mit Antwort von dem Verlag Otto H. Hess an Max Horkheimer, 1954; 1 Brief von Professor Gerhard Hess an Max Horkheimer, 1953; 1 Drucksachevon dem Hessischer Arbeitsausschuss gegen Rekrutierung, 1952; 1 Brief mit Beilage von dem Hotel Hessischer Hof an Max Horkheimer, 1956; 1 Brief mit Antwort von dem Hessischer Landesverband für Erwachsenenbildung an Max Horkheimer, 1956; 2 Briefe mit Antwort und Beilage von Marc Heurgon an Max Horkheimer, 1958; 1 Brief mit Beilage von Ruth Heydebrand an Max Horkheimer, [1955]; 1 Brief mit Antwort von Professor Frederick W. J. Heuser an Max Horkheimer, 1954; 2 Briefe mit Antwort von Professor Joh Erich Heyde an Max Horkheimer, 1958; 1 Befürwortung von Wolf von Heydebrand an Max Horkheimer, 1954; 1 Brief mit Antwort von Professor Heinz Joachim Heydorn an Max Horkheimer, 1953; 1 Brief mit Antwort und Beilage von dem Arzt Otto Heymann an Max Horkheimer, 1955; 5 Briefe zwischen dem Devisenberater und Steuerhelfer Joseph Christ und Max Horkheimer, 1955, 1956, 1961; 1 Brief von dem Office of the United States High Commissioner for Germany an Max Horkheimer, 1953; 1 Lebenslauf von Elen B. Hill, ohne Jahr; 1 Brief von Kurt H. Wolff an Max Horkheimer, 1952; 1 Brief von Rolf Himmelreich an Max Horkheimer, 1956; 1 Brief mit Antwort von Dr. Rolf Hinder an Max Horkheimer, 1953; 1 Brief mit Antwort von Anton Hinsinger an Max Horkheimer, 1953; 1 Brief mit Antwort von dem Hippokrates-Verlag an Max Horkheimer, 1952; 1 Brief von Bernice L. Hirsch anMax Horkheimer, 1957; 4 Briefe und Beilagen zwischen dem Historiker und Soziologe Helmut Hirsch an Max Horkheimer, 1951-1954, 25.05.1951; 3 Briefe mit Antwort von Lux Hirsch an Max Horkheimer, 1958; 1 Brief mit Antwort von Trude Hirschberg an Max Horkheimer, 1951; 1 Brief mit Antwort von Ingineur Paul F. Hirschfelder an Max Horkheimer, 1952; 1 Brief von Johannes Hirzel an Max Horkheimer, 1955; 1 Brief mit Antwort von dem Historisches Seminar Köln an Max Horkheimer, 1956; 1 Brief mit Antwort und Beilage von Professor Wolfgang Hochheimer an Professor Theodor W. Adorno, 1952; 2 Briefe von Max Horkheimer an Professor Wolfgang Hochheimer, 1953, 1954; 2 Memoranden von der Deutschen Gesellschaft für Psychologie, 1953; 1 Brief mit Beilage von Stud. phil. Erna Hochleitner an Max Horkheimer, 1956; 1 Brief mit Antwort von Professor Helmut Coing an Max Horkheimer, 1957; 3 Briefe mit Antwort von der Hochschule für Sozialwissenschaften Wilhelmshaven an Max Horkheimer, 1957, 1958; 1 Brief von Max Horkheimer an die Hochschule für Wirtschafts- und Sozialwissenschaften Nürnberg, 1953; 2 Drucksachen von dem Hochschul-Dienst, 1952; 2 Drucksachen von der Hochschule für politische Wissenschaften München, 1952; 1 Brief mit Antwort von Dr. Wolfram Hodermann an Max Horkheimer, 1951; 4 Briefe zwischen Dr. phil. Walter Höllerer und Max Horkheimer, 1956; 1 Brief mit Antwort von Privatdozent Dr. phil. Walter Hoeres anMax Horkheimer, 1956; 2 Briefe mit Antwort von Stud. phil. Charlotte Hoffmann an Max Horkheimer, 1950; 3 Briefe mit Antwort und Beilage von Professor Walter Hoffmann an Max Horkheimer, 1950-1955; 1 Brief mit Antwort von Wolfhart E. V. Hoffmann an Max Horkheimer, 1953; 1 Brief von Max Horkheimer an Dr. Werner Hofmann, 1956; 1 Glückwunschtelegramm mit Antwort von Ernst und Karl Hohner, 1953; 1 Brief von Dozent Uvo Hölscher an Max Horkheimer, 1950; 2 Briefe mit Antwort von Professor Dr. med. K. Holldack an Max Horkheimer, 1957; 2 Briefe mit Antwort von Dipl. Landwirt Bernhard Hollenhorst an Max Horkheimer, 1956; 1 Brief von Hans Heinz Holz an Max Horkheimer, 1951; 2 Briefe mit Antwort und Beilage von Dr. phil. Rudolf Holzinger an Max Horkheimer, 1951, 1952; 1 Brief mit Antwort von Jakob Hommen an Max Horkheimer, 1953; 1 Brief von Adele Hoppe anMax Horkheimer, 1953; 1 Brief mit Antwort von Dr. jur. Anton Horn an Max Horkheimer, 1954; 1 Brief mit Antwort von Dr. phil. Emil Horn an Max Horkheimer, 1953; 1 Brief von der Landesabgeordneten Ruth Horn an H. Maidon, 1953; 1 Brief mit Antwort von Reg.-Direktor Dr. phil. Kurt Horstmann an Max Horkheimer, 1953; 1 Brief von dem Hotel Baur au Lac an H. Maidon, 1958; 2 Briefe mit 1 Antwort von dem Hotel Frankfurter Hof an Max Horkheimer, 1956, 1958; 1 Brief mit Antwort von dem Hotel Stafflenberg an H. Maidon, 1953; 1 Brief von dem Hotel Vier Jahreszeiten, München an Max Horkheimer, 1951; 1 Brief von Max Horkheimer an Jean J. Hubener, 1951; 2 Briefe mit Antwort und Beilage von Susanna Huber-Weisser an Max Horkheimer, 1956; 1 Todesanzeige von dem Sozialgerichtsdirektor Gustav Adolf Hünniger, 1955; 1 Brief von dem Oberstudiendirektor F. Huf an Max Horkheimer, 1952; 1 Brief mit Antwort von Professor H. D. Huggins an Max Horkheimer, 1954; 2 Briefe mit 1 Antwort und 1 Beilage von dem Humboldt-Verlag, Wien-Stuttgart an Max Horkheimer, 1951; 1 Brief von Helge Pross an stud. rer. pol. Kristian Hungar, 1957; 1 Brief von Helmut Hungerland an Max Horkheimer, 1950; 1 Brief mit Antwort von James R. Huntley an Max Horkheimer, 1954; 1 Brief von Professor Robert Maynard Hutchins an Max Horkheimer, 1957;
Ornithógalum umbellatum L. und ruthenicum P.C. Bouché : Zwei Milchsterne auf grösseren Rasenparthien
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It is largely unknown if and how persistent organic pollutants (POPs) affect the transfer of maternal hormones to eggs. This occurs despite an increasing number of studies relating environmental conditions experienced by female birds at the time of egg formation to maternal hormonal effects. Here we report the concentrations of maternal testosterone, 17beta-estradiol and major classes of POPs (organochlorines, brominated flame retardants and metabolically-derived products) in the yolk of unincubated, third-laid eggs of the glaucous gull (Larus hyperboreus), a top-predator in the Arctic marine environment. Controlled for seasonal and local variation, positive correlations were found between the concentrations of certain POPs and testosterone. Contaminant-related changes in the relative concentrations of testosterone and 17beta-estradiol were also observed. In addition, yolk steroid concentrations were associated with contaminant profiles describing the proportions of different POPs present in the yolk. Eggs from nests in which two sibling eggs hatched or failed to hatch differed in POP profiles and in the relative concentrations of testosterone and 17beta-estradiol. Although the results of this correlative study need to be interpreted with caution, they suggest that contaminant-related changes in yolk steroids may occur, possibly affecting offspring performance over and above toxic effects brought about by POPs in eggs.
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Behavioural field observations are increasingly being used in ecotoxicological research to identify potential adverse effects of exposure to persistent organic pollutants (POPs). We investigated thermal conditions inside the nest and parental behaviour of glaucous gulls, Larus hyperboreus, breeding in the Norwegian Arctic in relation to the concentrations of major classes of POPs (organochlorines, brominated flame retardants and metabolically derived products) accumulated in their blood. Most notably, nest temperature was negatively correlated with the concentrations of the sum of DDT, sum of PCB and several quantitatively minor POP classes within the incubating parent. To investigate the relationship between incubation ability and parental POP exposure further, we experimentally increased the costs of incubation by artificially increasing the clutch size from two to four eggs. Clutch enlargement was followed by a decrease in nest temperature, but this drop in temperature was not associated with POP concentrations within the incubating parent. However, males, which had higher POP concentrations and lower white blood cell counts than females, seemed less able to maintain nest temperature. There was virtually no evidence to suggest that the sum of PCB or DDT were associated with changes in the time a bird spent incubating. However, there was some indication that nest site attendance by nonincubating males was negatively related to the sum of DDT, suggesting that nest protection may have been compromised. The results suggest that adverse effects of parental POP exposure may occur through suboptimal thermal conditions for embryo development and possibly increased egg predation risk.
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Time variable gravity fields, reflecting variations of mass distribution in the system Earth is one of the key parameters to understand the changing Earth. Mass variations are caused either by redistribution of mass in, on or above the Earth's surface or by geophysical processes in the Earth's interior. The first set of observations of monthly variations of the Earth gravity field was provided by the US/German GRACE satellite mission beginning in 2002. This mission is still providing valuable information to the science community. However, as GRACE has outlived its expected lifetime, the geoscience community is currently seeking successor missions in order to maintain the long time series of climate change that was begun by GRACE. Several studies on science requirements and technical feasibility have been conducted in the recent years. These studies required a realistic model of the time variable gravity field in order to perform simulation studies on sensitivity of satellites and their instrumentation. This was the primary reason for the European Space Agency (ESA) to initiate a study on ''Monitoring and Modelling individual Sources of Mass Distribution and Transport in the Earth System by Means of Satellites''. The goal of this interdisciplinary study was to create as realistic as possible simulated time variable gravity fields based on coupled geophysical models, which could be used in the simulation processes in a controlled environment. For this purpose global atmosphere, ocean, continental hydrology and ice models were used. The coupling was performed by using consistent forcing throughout the models and by including water flow between the different domains of the Earth system. In addition gravity field changes due to solid Earth processes like continuous glacial isostatic adjustment (GIA) and a sudden earthquake with co-seismic and post-seismic signals were modelled. All individual model results were combined and converted to gravity field spherical harmonic series, which is the quantity commonly used to describe the Earth's global gravity field. The result of this study is a twelve-year time-series of 6-hourly time variable gravity field spherical harmonics up to degree and order 180 corresponding to a global spatial resolution of 1 degree in latitude and longitude. In this paper, we outline the input data sets and the process of combining these data sets into a coherent model of temporal gravity field changes. The resulting time series was used in some follow-on studies and is available to anybody interested.