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81.
82.
A 45‐day feeding trial was conducted to study the stress ameliorating and immunomodulatory role of microbial levan in Cyprinus carpio fry exposed to sublethal dose (1/10th LC50) of fipronil [(±)‐5‐amino‐1‐(2,6‐dichloro‐α,α,α‐trifluoro‐p‐tolyl)‐4‐trifluoromethylsulfinylpyrazole‐3‐carbonitrile]. Two hundred and twenty‐five fry were randomly distributed in five treatments in triplicates. Four purified diets were prepared with graded levels of microbial levan. Five different treatment groups were levan control L0P0 (basalfeed + 0% levan without exposure to pesticide); pesticide control L0P1 (basalfeed + 0% levan with exposure to pesticide); L0.25P1 (basalfeed + 0.25% levan with exposure to pesticide); L0.50P1 (basalfeed + 0.50% levan with exposure to pesticide) and L0.75P1 (basalfeed + 0.75% levan with exposure to pesticide). Lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and fructose‐1,6‐diphosphatase (FDPase) activites were significantly (P < 0.05) increased, whereas alkaline phosphatase (ALP), adenosine triphosphatase (ATPase) and acetyl choline esterase (AchE) activities were significantly (P < 0.05) reduced in higher levan‐fed groups. RBC, haemoglobin and WBC counts were significantly (P < 0.05) increased in the levan‐fed groups. Similar trends were also observed for the total serum protein, globulin, NBT and lysozyme activities. Blood glucose and serum cortisol exhibited a third order polynomial relationship with increasing level of dietary levan. Overall result showed stress ameliorating, immunostimulating and protective role of microbial levan against fipronil‐induced stress in C. carpio fry at 0.75% level of dietary levan supplementation.  相似文献   
83.
Rhizoctonia solani is a soil-borne basidiomycete fungus with a necrotrophic lifestyle being classified into fourteen reproductively incompatible anastomosis groups (AGs). AG3-PT (a potato subgroup) is associated with quantitative and qualitative yield losses through stem canker and black scurf in potato. Here we present the first draft sequence of the R. solani [AG3-PT] strain RS-20 with a G-C content of 48.3%. It consists of 11,431 total predicted protein coding regions including 181 tRNA and 31 rRNA coding genes. The initial pBLAST revealed more than 97% hits among AG groups where as only 1.7% of genes hit with other organisms. The R. solani genome is found to be dominated with tri mer repeats. The genome-wide evolutionary studies revealed the close association of AG3-PT with AG3. The draft sequence represents a helpful resource not only for understanding the core genes involved in pathogenecity but also evolution and adaptive behaviour within the R. solani species complex.  相似文献   
84.
The serum-neutralization test (SN), enzyme-linked immunosorbent assay (ELISA) and the radial immunodiffusion enzyme assay (RIDEA) were compared for the detection of pseudorabies (PRV) antibodies in swine sera. A total of 1285 serum samples were tested. All three tests were considered useful in determining the PRV antibody status of swine on a herd basis, but available evidence supports the continued use of SN as the definitive test because of possible false positive reactions associated with ELISA and RIDEA.  相似文献   
85.
  1. The use of miniaturized electronic tracking devices has illuminated our understanding of seabird distributions and habitat use, and how anthropogenic threats interact with seabirds in both space and time. To determine the year-round distribution of adult Campbell albatross (Thalassarche impavida), a single-island endemic, breeding only at Campbell Island in New Zealand's subantarctic, a total of 68 year-long location data sets were acquired from light-based geolocation data-logging tags deployed on breeding birds in 2009 and 2010.
  2. During the incubation and chick-guard phases of the breeding season, birds used cool (<10°C) waters over the Campbell Plateau, but also ranged over deeper, shelf-break and oceanic waters (4,000–5,500 m) beyond the Plateau. Later in the breeding season, during post-guard chick-rearing, Campbell albatrosses exploited generally deep waters (4,000–5,000 m) beyond the Campbell Plateau.
  3. During the non-breeding period, adults tended to move northwards into warmer (approximately 15°C) waters and occupied areas beyond western Australia in the west to offshore from Chile in the east. Overall, about 30% of adults spent some of their non-breeding period in the central and eastern Pacific Ocean, substantially expanding the previously reported range for this species.
  4. One bird, that failed in its breeding attempt in October 2009, departed Campbell Island and circumnavigated the southern oceans before being recaptured back at Campbell Island in October 2010. This is the first example of an annually-breeding albatross species completing a circumnavigation between breeding attempts.
  5. Overlap with fishing effort, using data from the Global Fishing Watch database, was assessed on a monthly and seasonal basis. Generally, levels of overlap between Campbell albatross and fishing effort were relatively low during the breeding season but were approximately 60% higher during the non-breeding period, underlining the need for international initiatives to safeguard this species.
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86.
Further heterogeneity of human alpha interferon mRNA species   总被引:4,自引:0,他引:4  
Translationally active (in Xenopus oocytes) human alpha interferon (IFN) messenger RNA's (mRNA's) derived from Sendai virus--induced leukocyte cultures display a bimodal distribution of RNA lengths on electrophoresis through agarose-CH3HgOH gels. The major population (alpha s) consists of mRNA of length 0.7 to 1.4 kilobases, while the minor population (alpha L) consists of RNA of length 1.6 to 3.5 kilobases. Induction of human leukocytes in the presence of 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB; 100 micromolar) appears to inhibit the accumulation of IFN-alpha s and to enhance that of IFN-alpha L mRNA's (average length about 1.8 kilobases in preparations from DRB-treated cells). Interferons derived from the alpha s mRNA's represent the group of previously recognized alpha interferons while the alpha L interferons are distinguishable from this group by their lower heterospecific activity on bovine cells compared to human cells, their apparent slower mobility in sodium dodecyl sulfate--polyacrylamide gels, and their apparent heteroclitic response toward an antiserum to IFN-alpha.  相似文献   
87.
Summary Non-destructive observations of the growth of every tuber on nine individual potato plants grown in the field revealed great variation in total number of tubers per plant, total tuber volume per plant and the volumes of individual tubers. The number of tubers was established early but the rates of increase in total and mean tuber volume changed greatly up to a short time before the final harvest. The growth rates of individual tubers on each plant also showed great variation and it was clear that the largest tuber at any one time was not necessarily the largest at a later time. Both the duration of the main period of growth and growth rates varied and acted independently to determine the final size of a tuber.
Zusammenfassung Viele Jahre wurden zur Ernte die Variationen in der Knollenzahl und-gr?sse zwischen und an Einzelpflanzen beobachtet. Die Ursachen für diese Variationen sind schwer verst?ndlich und einer der Gründe ist der Mangel an Information über die Art wie die Einzelknollen w?hrend der Periode des Knollenwachstums wachsen. Die vorliegende Arbeit umfasst die Messung des Volumens aller Knollen von 9 Pflanzen, die in speziellen Gef?ssen im Feld gewachsen waren, zu 7 verschiedenen Terminen zwischen der Knollenbildung und dem Absterben des Krautes. Die Spezialbeh?lter hatten einen mit Sand gefüllten oberen Plastikring, in dem die Stolonen und Knollen wuchsen. Der Sand wurde in Zeitabst?nden entfernt und wieder aufgefüllt, um ein nicht st?rendes Messen des Volumens der Einzelknollen zu gestatten. Die Wurzeln der Pflanzen entwickelten sich im natürlichen Ackerboden unter dem Ring (Abb. 1). Die Zahl der Knollen/Pflanze schwankte zwischen 1 und 12 (Tab. 1) und das Volumen aller Knollen/Pflanze von 60 bis 600 cm3 (Abb. 2). Die Muster der Gr?ssenzunahme variierten. Vier Pflanzen zeigten im allgemeinen eine lineare Zunahme des Volumens, drei eine reduzierte Zunahme in der Mitte des Gr?ssenwachstums und eine steigerte — nach einem langsamen Beginn —die Zunahme (Abb. 2). Die Steigerung im durchschnittlichen Knollenvolumen/Pflanze variierte ebenfalls (Abb. 3), aber infolge der Unterschiede in der Zahl der Knollen/Pflanze, war die Rangfolge der Pflanzen nicht die selbe wie beim Gesamtvolumen. Abb. 4 (a-h) zeigt die Volumenzunahme von Einzelknollen. Die Variation schliesst fast alle theoretischen M?glichkeiten ein (verschiedene Startzeiten, verschiedene Zuwachsraten im Volumen, verschiedene Daten des Wachstumsstillstandes). In der Diskussion werden einige der m?glichen Gründe für die Variabilit?t innerhalb der Pflanze geprüft und es wird versucht, den Schluss zu ziehen, dass die Einzelknollen wahrscheinlich ihr Wachstum selbst bestimmen.

Résumé La variation du nombre et de la taille des tubercules d'une même plante et de différentes plantes au moment de la récolte a été observée depuis de nombreuses années. Les causes de variation sont mal comprises, en particulier parce que l'on manque d'informations sur la croissance de chaque tubercule pris individuellement tout au long de la période de végétation. Cette publication décrit les travaux de mesure du volume de tous les tubercules de neuf plantes cultivées dans des unités spéciales disposées dans le champ; les mesures ont été effectuées à 7 dates entre la tubérisation et le défanage. Les unités spéciales (fig. 1) ont un anneau supérieur rempli de sable dans lequel poussent les stolons et les tubercules. Le sable est enlevé, puis remplacé pour permettre une mesure non destructive du volume de chaque tubercule. Les racines des plantes se développent dans le sol du champ, en-dessous des anneaux. Le nombre de tubercules par plant a varié de 1 ⦏ 12 (tableau 1) et le volume total de tubercules par plante s'est étendu de 60 à 600 cm3 (fig. 2). Les fa?ons de tubériser ont également varié. Les vitesses de croissance en volume de 4 plantes ont été tout le temps linéaires, celles de 3 plantes ont été réduites pendant la moitié de la tubérisation, et celle d'une plante a augmenté après un départ lent (fig. 2). Les vitesses de croissance du volume moyen des tubercules par plante ont été aussi très variables (fig. 3), mais à cause des différences de nombre de tubercules par plante, l'ordre des plantes n'était pas le même que pour le volume brut. La fig. 4 (a-h) montre l'augmentation de volume des tubercules pris individuellement. La variation inclut presque toutes les possibilités théoriques (différentes dates d'initiation, différentes vitesses de croissance de volume, différentes dates de fin de croissance). Dans la discussion, plusieurs des causes possibles de variabilité intra-plante sont examinées et il est suggéré que chaque tubercule détermine très probablement sa propre croissance.
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