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2.
Die Aufnahme von 137Cs und 90Sr durch verschiedene Sommerrapsgenotypen aus kontaminiertem Boden wurde geprüft. Statistisch gesicherte Unterschiede bei der Aufnahme von Radionukliden zwischen den Genotypen konnten festgestellt werden. Die Aufnahme von 137Cs und 90Sr ist bei den einzelnen Sorten nicht gleichsinnig. Nur ein geprüfter Genotyp nahm sowohl geringe Mengen von 137Cs, als auch von 90Sr auf. Die mittleren jährlichen Schwankungen in der Radionuklidaufnahme waren größer, als die Unterschiede zwischen den Genotypen.  相似文献   
3.
The chlorophyll fluorescence kinetics of ‘Jonagold’ and ‘Cox’ apples, stored under different conditions to induce mealiness, were measured. Three different storage conditions were considered causing three mealiness levels: not mealy, moderately and strongly mealy. Also destructive measurements of the texture (firmness, hardness, juice content and soluble solids content) were done. Classification into different mealiness levels based on the fluorescence measurements was more performant than a classification based on the destructive measurements. To estimate the mealiness level in a non-destructive way from the fluorescence features, a number of different classifiers were constructed. Quadratic discriminants and supervised and unsupervised neural networks were tested and compared. The self-organising map gives promising results when compared with the multi-layer perceptrons and quadratic discriminant analysis. The different advantages of the constructed classifiers suggest that fluorescence can be used in an automatic sorting line to assess certain types of mealiness.  相似文献   
4.
Zusammenfassung Die Sedimentationskonstante S 20.w ° des Kartoffelvirus M (KVM) betr?gt 167±1 S. Die Konzentrationsabh?ngigkeit ergibt sich aus der Beziehung s 20.w c =(167−33×c) S. Die Schwebedichte des KVM in C?siumchlorid (⌕ C5C1 25 ) betr?gt 1,321 bis 1,322 g/ml. Mit Hilfe der SDS-Polyacrylamid-Gelektrophorese fanden wir zwei Proteine mit Molekülmassen von 35 700 und 33 000 Dalton. Die Nukleins?ure des KVM ist eine einstr?ngige RNS mit einer Molekülmasse von 2,38×106 Dalton (nicht denaturierende Bedingungen) bzw. 2,14×106 Dalton (nach Formaldehydbehandlung). Damit ist das KVM ein typischer Vertreter der Carlavirus-Gruppe.
Summary Particles of potato virus M (PVM) were purified by the method of Proll & Richter (1979). After sugar density gradient centrifugation, preparations had a high level of purity and were homogeneous when examined under the electron microscope and in the analytical ultra-centrifuge. The sedimentation constant of particles (s°) is 167±1 S and the concentration relation s 20.w c =(167−33×c)S, where c is in mg/ml. The density of the PVM particles in caesium chloride (⌕ C5C1 25 ) is 1.321 to 1.322 g/ml, with tobacco mosaic virus particles (density=1.325 g/ml) as a standard. In SDS-polyacrylamide gel electrophoresis, PVM protein sub-units migrated as two compounds with apparent sizes of 35 700 and 33 000 daltons, respectively. PVM nucleic acid is single stranded RNA, as shown by its positive orcinol and negative diphenylamine reactions, its degradation by RNase and its temperature melting curve. The RNA comprised 5.4% of the particle weight and its estimated molecule size was 2.38×106 daltons (undenatured) and 2.14×106 daltons (treated with formaldehyde). Physicochemical data on PVM are summarized in Table 1. The cryptogram of PVM is R/1: 2.4/5.4: E/E: S/Ap, carlavirus group.

Résumé é virus M de la pomme de terre (PVM) a été urifié selon la méthode Proll & Richter 979). Après deux centrifugations selon la chnique du gradient de sucrose, nous avons btenu des préparations purifiées qui se sont firmées très homogènes au microscope ectronique, ainsi qu’avec l’ultracentrifugeuse analytique. Nous avons observé un effet de concentration de la valeur S et avons éterminé la constante de sédimentation (sO) à aide de distribution de S dans une zone de concentration de 0,5 à 0,1 mg de virus/ml à 57±1 S. L’effet de concentration peut être obtenu ar la relation s 20.w c =(167−33×c)S, dont c at à utiliser en mg/ml. La densité spécifiquedu PVM dans le aloride de césium (⌕ C5C1 25 ) est de 1,321 à 322 g/ml avec le virus de la mosa?que du abac comme marqueur, dont la densité est de 1,325 g/ml. Les masses moléculaires des capsomers ont été déterminées à l’aide de la SDS-polyacrylamide-gel-electrophorèse. Nous avons observé deux zones de protéines dont la masse moléculaire calculée fut de 35 700 et 33 000 dalton. L’acide nucléique du PVM comprend une spirale ARN; ceci a été obtenu avec la réaction positive d’orcine, des essais de catabolisme avec la RNase et de la courbe de fusion. Le poids représente 5,4 % de celui de la particule. La masse moléculaire est de 2,38×106 dalton (conditions non dénaturantes) 2,38×106 (après traitement au formaldéhyde). Dans le tableau 1 sont résumées les données physicochimiques du PVM selon Proll & Richter (1979). Le cryptogramme suivant a été obtenu: R/1: 2,4/5,4: E/E: S/Ap, ce qui permet de classer ce virus dans le groupe Carla.
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5.
To evaluate the potential benefits and risks associated with tea consumption it is important to identify the constituents of this beverage. Levels of some minerals, caffeine and catechins in green tea samples commercialized in Portugal were evaluated. Potassium is the metal present in larger amount (92–151 mg/l). The content of sodium, calcium, fluoride, aluminium, manganese and iron were 35–69, 1.9–3.5, 0.80–2.0, 1.0–2.2, 0.52–1.9, 0.020–0.128 mg/l, respectively. Chromium and selenium were not detected. The resulting data showed considerable variability in catechins content. The levels of epigallocatechin gallate (EGCG) ranged from 117 to 442 mg/l, epicatechin 3-gallate (EGC) from 203 to 471 mg/l, epigallocatechin (ECG) from 16.9 to 150 mg/l, epicatechin (EC) from 25 to 81 mg/l and catechin (C) from 9.03 to 115 mg/l. Caffeine contents in the green tea infusions studied were between 141–338 mg/l. Green tea infusions provide significant amounts of catechins and could be an important source of some minerals.  相似文献   
6.
Trilostane, a 3beta-hydroxysteroid dehydrogenase inhibitor, has been used successfully over the last few years for the treatment of canine pituitary-dependent hyperadrenocorticism. In a prospective study of 19 dogs with pituitary-dependent hyperadrenocorticism, the adrenal glands were measured before and at least 6 months after initiation of trilostane therapy. Right adrenal gland length and caudal pole thickness and left adrenal gland caudal pole thickness increased significantly (p < or = 0.05); there was no significant change in left adrenal gland length. Enlargement of adrenal glands during trilostane therapy may occur as a result of suppression of the negative feedback mechanism affecting cortisol production.  相似文献   
7.
OBJECTIVE: To investigate whether volumetric capnography indices could be used to differentiate between horses without recurrent airway obstruction (RAO) and horses with RAO that were in clinical remission or that had clinically apparent RAO. ANIMALS: 70 adult Swiss Warmblood horses (20 used for pleasure riding and 50 used for dressage or show jumping). PROCEDURE: Horses were allocated to 4 groups on the basis of history, clinical signs, results of endoscopy, and cytologic findings (group 1, 21 healthy horses; group 2, 22 horses with RAO that were in remission; group 3, 16 horses with mild RAO; group 4, 11 horses with exacerbated RAO). Expiratory volume and CO2 curves were recorded by use of a computerized ultrasonic spirometer. Volumetric capnograms were plotted, and derived indices were calculated. RESULTS: Dead-space volume (VD) was calculated by use of the Bohr equation (VD(Bohr)) and for physiologic VD (VD(phys)). Ratios for VD(Bohr) to expiratory tidal volume (VT) and VD(phys) to V(T) as well as an index of effective CO2 elimination were significantly different among groups of horses. Age and use of the horses also significantly affected volumetric capnography indices. CONCLUSIONS AND CLINICAL RELEVANCE: Ratios of VD(Bohr) to VT and VD(phys) to VT as well as an index of effective CO2 elimination were sufficiently sensitive measures to distinguish between healthy horses and horses with RAO in remission. To optimize the ability of volumetric capnography indices to differentiate among horses in heterogeneous populations, it is important to account for effects of age and specific use of the horses.  相似文献   
8.
A raised concentration of serum cardiac troponin I (cTnI) is a sensitive marker of cardiac myocyte injury in the cat and assays developed for its measurement in human patients have been validated in the cat. Raised levels have been associated with a number of cardiac insults including hypertrophic cardiomyopathy and trauma. Hyperthyroidism is a common disease of older cats and excess thyroid hormone is known to produce significant cardiovascular effects in this species. This study evaluated the effect of treatment for hyperthyroidism with radioactive iodine on cTnI concentration, assessed the association between thyroxin levels and glomerular filtration rate (GFR) and cTnI concentration in cats treated for hyperthyroidism and described changes in echocardiographic parameters following treatment. Prior to the treatment serum cTnI was measured and echocardiography performed, thyroxin, cTnI, and echocardiography were then repeated at various time points following radioisotope therapy. The results show that higher thyroxin levels were significantly (P=0.002) associated with a higher likelihood of the cat presenting with detectable levels of cTnI. No significant association was found between GFR and presence of detectable levels of cTnI. Furthermore the results indicate that the effects of hyperthyroidism on echocardiographic parameters appear considerably less in this study than in previous studies and that the main outcome of treatment on these parameters is a significant reduction in fractional shortening (P=0.006). These results suggest that chronic exposure to excess thyroid hormone may induce myocyte damage of sufficient severity to raise serum cTnI concentration in a proportion of cats that resolves following establishment of a euthyroid state.  相似文献   
9.
The IgE specific Fc-? receptor test is widely used for serological evaluation of allergic canine patients. Aim of the study was to evaluate intra- and interlaboratory variability in three independent laboratories. Duplicate serum aliquots from 15 atopic dogs were submitted simultaneously to 3 laboratories (LA, LB, LC), which subsequently performed the test in a blinded fashion. LA and LC analysed sera for 35 allergens and expressed the results as optical density units (OD), while LB analysed 15 allergens and provided reaction grades (RG). Results were compared with three factorial ANOVA. Intralaboratory variability was evaluated by calculating the dispersion factor for data of LA and LC and standard deviation (SD) for LB. Correlation coefficients (r) were used to evaluate interlaboratory variability. Depending on the allergens, intralaboratory dispersion factor for LA and LC varied from 1.15 to 6.63 and 1.19 to 6.17, respectively. In LB the SD varied between 0 and 0.6 RG. Regarding interlaboratory variability, correlation of OD values between LA and LC was excellent (r > 0.8, p < 0.001) for 13 of 35 allergens. There was a significant difference in OD results for 9 allergens. The results were significantly correlated (r > 0.8, p < 0.001) for all except 3 allergens (Dermatophagoides pteronyssinus, mixed grasses, nettle). As far as negative/positive results were concerned, intralaboratory differences were 3.14% and interlaboratory differences were 4.76%.  相似文献   
10.
In this study, thirteen sponge-derived terpenoids, including five linear furanoterpenes: furospinulosin-1 (1), furospinulosin-2 (2), furospongin-1 (3), furospongin-4 (4), and demethylfurospongin-4 (5); four linear meroterpenes: 2-(hexaprenylmethyl)-2-methylchromenol (6), 4-hydroxy-3-octaprenylbenzoic acid (7), 4-hydroxy-3-tetraprenyl-phenylacetic acid (8), and heptaprenyl-p-quinol (9); a linear triterpene, squalene (10); two spongian-type diterpenes dorisenone D (11) and 11β-acetoxyspongi-12-en-16-one (12); a scalarane-type sesterterpene; 12-epi-deoxoscalarin (13), as well as an indole alkaloid, tryptophol (14) were screened for their in vitro activity against four parasitic protozoa; Trypanosoma brucei rhodesiense, Trypanosoma cruzi, Leishmania donovani and Plasmodium falciparum. Cytotoxic potential of the compounds on mammalian cells was also assessed. All compounds were active against T. brucei rhodesiense, with compound 8 being the most potent (IC50 0.60 μg/mL), whereas 9 and 12 were the most active compounds against T. cruzi, with IC50 values around 4 μg/mL. Compound 12 showed the strongest leishmanicidal activity (IC50 0.75 μg/mL), which was comparable to that of miltefosine (IC50 0.20 μg/mL). The best antiplasmodial effect was exerted by compound 11 (IC50 0.43 μg/mL), followed by compounds 7, 10, and 12 with IC50 values around 1 μg/mL. Compounds 9, 11 and 12 exhibited, besides their antiprotozoal activity, also some cytotoxicity, whereas all other compounds had low or no cytotoxicity towards the mammalian cell line. This is the first report of antiprotozoal activity of marine metabolites 1–14, and points out the potential of marine sponges in discovery of new antiprotozoal lead compounds.  相似文献   
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