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111.
The origin of Galactic cosmic rays is a century-long puzzle. Indirect evidence points to their acceleration by supernova shockwaves, but we know little of their escape from the shock and their evolution through the turbulent medium surrounding massive stars. Gamma rays can probe their spreading through the ambient gas and radiation fields. The Fermi Large Area Telescope (LAT) has observed the star-forming region of Cygnus X. The 1- to 100-gigaelectronvolt images reveal a 50-parsec-wide cocoon of freshly accelerated cosmic rays that flood the cavities carved by the stellar winds and ionization fronts from young stellar clusters. It provides an example to study the youth of cosmic rays in a superbubble environment before they merge into the older Galactic population.  相似文献   
112.
In the pig a high growth potential seems to favour a disposition for skeletal problems. Hormones of growth hormone (GH)/insulin-like growth factor (IGF)-I axis as well as cortisol and gonadal steroids are endocrine determinants of the anabolic potential but their effects on bone turnover in pigs have not been described. Thus, key hormones were either infused for 7 days (cortisol, 5alpha-dihydrotestosterone (DHT), oestradiol) or influenced by Metyrapone (inhibition of cortisol synthesis) or energy deficit (increasing GH). Each treatment was carried out in six growing barrows/treatment. Bone turnover was characterized by daily measurements indirect parameter of osteoblastic and osteoclastic activity, osteocalcin (OC) and tartrate-resistant acid phosphatase (TRAP) respectively. All treatments except cortisol infusion seemed to favour bone formation, as they led either to a pronounced increase in OC (Metyrapone: +14%) or to significantly reduced TRAP (DHT: -9%, E2: -17%, energy deficit: -25%) followed by significantly higher OC (DHT: +9%, E2: +6%, energy deficit: +18%). Cortisol infusion affected bone loss mainly by a severe inhibition of osteoblastic activity (OC: -61%). Some reactions are explained by direct effects of the infused gonadal steroids on bone cells (inhibition of osteoclasts) or of the experimentally modified cortisol levels (inhibition of osteoblasts by cortisol). Other effects seem to be mediated by concomitant changes of IGF-I (inhibition of osteoclasts after energy deficit or cortisol) and GH-secretion (increased osteoblastic activity during energy deficit), respectively. Consequences for co-ordinated bone turnover are discussed.  相似文献   
113.
Homocysteine and cobalamin status in German vegans   总被引:1,自引:0,他引:1  
OBJECTIVE: The study aimed to evaluate the homocysteine and cobalamin status of German vegans and determine whether the intake of very small amounts of foods of animal origin can improve this status. DESIGN AND SETTING: Cross-sectional study, Germany. SUBJECTS: The dietary and nutritional intakes of 131 vegans (73 women, 58 men; age range: 20.2-82.1 years) were evaluated using a general questionnaire and two food-frequency questionnaires. RESULTS: The prevalence of inadequate cobalamin status in volunteers of the German Vegan Study was 28.2%, and that of hyperhomocysteinaemia, 38.1%. Moderate vegans were affected to a lesser extent than were strict vegans. Duration of veganism and cobalamin concentration were inversely correlated (Spearman's r=-0.175, P=0.047). Folate concentration and erythrocyte aspartic acid aminotransferase activity were not correlated with plasma homocysteine concentration, but duration of veganism correlated positively with homocysteine concentration (Spearman's r=0.319, P<0.001). Cobalamin and homocysteine concentrations were inversely correlated (when controlling for duration of veganism; r=-0.602, P<0.001). CONCLUSION: Cobalamin status needs to be improved in order to minimise the risk of hyperhomocysteinaemia.  相似文献   
114.
Analysis of the hydrophilic fraction of cranberry juice by reversed-phase HPLC using an Aqua LUNA column with diode array or MS detection revealed the presence of quinic acid, malic acid, shikimic acid, and citric acid. For the first time, two iridoid glucosides were found in the juice. The two iridoid glucosides were shown to be monotropein and 6,7-dihydromonotropein by MS and NMR spectroscopy. A fast reversed-phase HPLC method for quantification of the hydrophilic carboxylic acids was developed and used for analyses of cranberry, lingonberry, and blueberry juices. The level of hydrophilic carboxylic acids in cranberries was 2.67-3.57% (w/v), in lingonberries 2.27-3.05%, and in blueberries 0.35-0.75%. In lingonberries both iridoid glucosides were present, whereas only monotropein was present in blueberries.  相似文献   
115.
Because the impact of agronomical factors on bakery products quality is still an insufficiently studied field, acrylamide contents of breads produced from flours of nine wheat, two rye, and two spelt varieties harvested in 2003 and 2004 were investigated. It could be demonstrated that acrylamide content in bread strongly depends on the cultivar, with extremes differing by a factor of 5.4 due to marked differences in free asparagine and crude protein contents. Nitrogen fertilization also resulted in elevated amino acid and protein contents, thus increasing acrylamide levels from 10.6 to 55.6 mug/kg. Independent of fertilization, harvest year turned out to be another factor influencing acrylamide formation. Breads produced from 2003 flours showed significantly higher acrylamide contents than those of 2004, which was ascribed to favorable light and temperature conditions during the cultivation period, thus enhancing amino acid and protein contents. Sprouting of the grain also resulted in significantly higher acrylamide levels, which was attributed to elevated enzyme activities and the formation of precursors from protein and starch. Furthermore, bakery products made from flours with higher extraction rates were shown to contain higher acrylamide levels resulting from extracted free asparagine and protein from the aleuron layers of the cereal grain.  相似文献   
116.
Zusammenfassung Im Verlaufe morphologisch-systematischer und biochemischer Untersuchungen ist in Gatersleben eine größereDatura-Kollektion entstanden, die in die Genbank übernommen wurde und für die Züchtung von Arzneipflanzen sowie für die Grundlagenforschung zur Verfügung steht. Probleme der Erhaltung dieser Kollektion in der Genbank werden diskutiert. In diesem Zusammenhang werden Keimungsverhalten und Reproduktionssystem besonders untersucht.Zur Dokumentation des Materials ist seine Identifikation notwendig. Daher wurde die GattungDatura, mit Ausnahme der SektionBrugmansia, revidiert. Bestimmungsschlüssel ermöglichen die Determination bis zu den infraspezifischen Sippen.Entwicklungstendenzen innerhalb der Gattung werden aufgezeigt.
Studies towards a monographic treatment of wild plant collections:Datura L., sectionsDutra Bernh.,Ceratocaulis Bernh. etDatura
Summary In the course of morphologic-taxonomical and biochemical studies a collection ofDatura has been brought together. The material has been incorporated into the gene bank and is available for breeding programmes in medicinal plants and for the use in basic research. Problems of maintaining of this collection in the gene bank are discussed. In this connection germination behaviour and breeding systems are studied.For the documentation of the material identification is necessary. Therefore, the genusDatura has been revised, excluding sect.Brugmansia. Keys are given for the determination of the species and also of the infra-specific taxa.Evolutionary trends within the genus are demonstrated.

:Datura L., sectionesDutra Bernh.,Ceratocaulis Bernh. etDatura
- , , . . . . Datura, Brugmansia, . . .
  相似文献   
117.
Zusammenfassung Auf Grund der Tatsache, daß 1, 1, 2, 3, 4, 5, 6-Heptachlor-cyclohexane (II) und 1, 2, 3, 4, 5, 6-Hexachlorcyclohexane (1) mit Zinkstaub praktisch quantitativ unter Bildung von Chlorbenzol (IV) bzw. Benzol (III) reagieren (Gl. 1 u. 2) und daß nach Williams und Daniels IV refraktometrisch neben III bestimmt werden kann, ließ sich ein Verfahren zur quantitativen Analyse von II in I-II-Gemischen ausarbeiten.Zur Chemie von Polyhalocyclohexanen, Mitt. XIV. — Zusammenfassung eines am 17. April 1951 in Mailand gehaltenen Vortrages. (Tab. 1 später ergänzt). Vgl. auch Partielle Halogenabspaltung, Mh. Chem.83, H. 1 (1952).Anschrift der Verff.: Berlin-Charlottenburg 9, Bolivarallee 8.  相似文献   
118.
Ohne ZusammenfassungAnm. der Schriftl.: Auszüge aus der Dissertationsarbeit: Untersuchungen über die Notwendigkeit der Dasselbekämpfung während der Älpung und ihre Verwirklichung durch therapeutische und prophylaktische Maßnahmen mit Hexachlorcyclohexanpräparaten  相似文献   
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